fix consul version in ci

Woodpecker CI
cleaned Docker process
2024-03-20 17:02:45 +00:00 · 2024-03-20 17:02:45 +00:00 · 2023-03-27 10:23:32 +02:00 · 2023-03-26 09:41:22 +02:00 · 2022-12-01 22:43:06 +01:00 · 2022-12-01 22:40:13 +01:00
100 changed files with 12457 additions and 87 deletions
--- a/.gitignore
+++ b/.gitignore
@ -2,3 +2,5 @@ bottin
 bottin.static
 config.json
 test/test
+result
+ldap.json
--- a/.woodpecker.yml
+++ b/.woodpecker.yml
@ -1,7 +1,3 @@
---
-kind: pipeline
-name: bottin
-
 steps:
 - name: build
  image: golang:stretch
@ -12,14 +8,8 @@ steps:
    - go test -i -c -o test

 - name: test_bottin
-  image: consul:latest
+  image: consul:1.15.4
  environment:
    BOTTIN_DEFAULT_ADMIN_PW: priZ4Cg0x5NkSyiIN/MpvWw4ZEy8f8s1 
  commands:
    - ash test/runner.sh
-
---
-kind: signature
-hmac: ff246a04c3df8a2f39c8b446dea920622d61950e6caaac886931bdb05d0706ed
-
-...
--- a/5
+++ b/5
@ -1,5 +0,0 @@
-FROM scratch
-
-ADD bottin.static /bottin
-
-ENTRYPOINT ["/bottin"]
--- a/README.md
+++ b/README.md
@ -1,6 +1,6 @@
 # Bottin

-[![Build Status](https://drone.deuxfleurs.fr/api/badges/Deuxfleurs/bottin/status.svg?ref=refs/heads/main)](https://drone.deuxfleurs.fr/Deuxfleurs/bottin)
+[![status-badge](https://woodpecker.deuxfleurs.fr/api/badges/38/status.svg)](https://woodpecker.deuxfleurs.fr/repos/38)

 <img src="https://git.deuxfleurs.fr/Deuxfleurs/bottin/raw/branch/main/bottin.png" style="height: 150px; display: block; margin-left: auto; margin-right: auto" />

@ -24,7 +24,7 @@ Features:
 - Access control through an ACL (hardcoded in the configuration file)


-A Docker image is provided on the [Docker hub](https://hub.docker.com/r/lxpz/bottin_amd64).
+A Docker image is provided on the [Docker hub](https://hub.docker.com/r/dxflrs/bottin) (built in `default.nix`).
 An example for running Bottin on a Nomad cluster can be found in `bottin.hcl.example`.

 Bottin takes a single command line argument, `-config <filename>`, which is the
@ -44,6 +44,17 @@ Bottin requires go 1.13 or later.
 To build Bottin, clone this repository outside of your `$GOPATH`.
 Then, run `make` in the root of the repo.

+## Releasing 
+
+```bash
+nix-build -A bin
+nix-build -A docker
+```
+
+```bash
+docker load < $(nix-build -A docker)
+docker push dxflrs/bottin:???
+```

 ## Server initialization

--- a/default.nix
+++ b/default.nix
@ -0,0 +1,55 @@
+let
+  pkgsSrc = fetchTarball {
+    # As of 2022-07-19
+    url = "https://github.com/NixOS/nixpkgs/archive/d2db10786f27619d5519b12b03fb10dc8ca95e59.tar.gz";
+    sha256 = "0s9gigs3ylnq5b94rfcmxvrmmr3kzhs497gksajf638d5bv7zcl5";
+  };
+  gomod2nix = fetchGit {
+    url = "https://github.com/tweag/gomod2nix.git";
+    ref = "master";
+    rev = "40d32f82fc60d66402eb0972e6e368aeab3faf58";
+  };
+
+  pkgs = import pkgsSrc { 
+    overlays = [
+      (self: super: {
+        gomod = super.callPackage "${gomod2nix}/builder/" { };
+      })
+    ];
+  };
+in rec {
+  bin = pkgs.gomod.buildGoApplication {
+    pname = "bottin-bin";
+    version = "0.1.0";
+    src = builtins.filterSource 
+      (path: type:  (builtins.match ".*/test/.*\\.(go|sum|mod)" path) == null) 
+      ./.;
+    modules = ./gomod2nix.toml;
+
+    CGO_ENABLED=0;
+
+    meta = with pkgs.lib; {
+      description = "A cloud-native LDAP server backed by a Consul datastore";
+      homepage = "https://git.deuxfleurs.fr/Deuxfleurs/bottin";
+      license = licenses.gpl3Plus;
+      platforms = platforms.linux;
+    };
+  };
+  pkg = pkgs.stdenv.mkDerivation {
+    pname = "bottin";
+    version = "0.1.0";
+    unpackPhase = "true";
+
+    installPhase = ''
+      mkdir -p $out/
+      cp ${bin}/bin/bottin $out/bottin
+    '';
+  };
+  docker = pkgs.dockerTools.buildImage {
+    name = "dxflrs/bottin";
+    config = {
+      Entrypoint = [ "${pkg}/bottin" ];
+      WorkingDir = "/";
+    };
+  };
+}
--- a/flake.lock
+++ b/flake.lock
@ -0,0 +1,79 @@
+{
+  "nodes": {
+    "gomod2nix": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "utils": "utils"
+      },
+      "locked": {
+        "lastModified": 1655245309,
+        "narHash": "sha256-d/YPoQ/vFn1+GTmSdvbSBSTOai61FONxB4+Lt6w/IVI=",
+        "owner": "tweag",
+        "repo": "gomod2nix",
+        "rev": "40d32f82fc60d66402eb0972e6e368aeab3faf58",
+        "type": "github"
+      },
+      "original": {
+        "owner": "tweag",
+        "repo": "gomod2nix",
+        "rev": "40d32f82fc60d66402eb0972e6e368aeab3faf58",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1653581809,
+        "narHash": "sha256-Uvka0V5MTGbeOfWte25+tfRL3moECDh1VwokWSZUdoY=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "83658b28fe638a170a19b8933aa008b30640fbd1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1669764884,
+        "narHash": "sha256-1qWR/5+WtqxSedrFbUbM3zPMO7Ec2CGWaxtK4z4DdvY=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "0244e143dc943bcf661fdaf581f01eb0f5000fcf",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "0244e143dc943bcf661fdaf581f01eb0f5000fcf",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "gomod2nix": "gomod2nix",
+        "nixpkgs": "nixpkgs_2"
+      }
+    },
+    "utils": {
+      "locked": {
+        "lastModified": 1653893745,
+        "narHash": "sha256-0jntwV3Z8//YwuOjzhV2sgJJPt+HY6KhU7VZUL0fKZQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "1ed9fb1935d260de5fe1c2f7ee0ebaae17ed2fa1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
--- a/flake.nix
+++ b/flake.nix
@ -0,0 +1,39 @@
+{
+  description = "A cloud-native LDAP server backed by a Consul datastore";
+
+  inputs.nixpkgs.url = "github:nixos/nixpkgs/0244e143dc943bcf661fdaf581f01eb0f5000fcf";
+  inputs.gomod2nix.url = "github:tweag/gomod2nix/40d32f82fc60d66402eb0972e6e368aeab3faf58";
+
+  outputs = { self, nixpkgs, gomod2nix }:
+  let
+    pkgs = import nixpkgs {
+      system = "x86_64-linux";
+      overlays = [
+        (self: super: {
+          gomod = super.callPackage "${gomod2nix}/builder/" { };
+        })
+      ];
+    };
+    bottin = pkgs.gomod.buildGoApplication {
+      pname = "bottin";
+      version = "0.1.0";
+      src = builtins.filterSource
+        (path: type:  (builtins.match ".*/test/.*\\.(go|sum|mod)" path) == null)
+        ./.;
+      modules = ./gomod2nix.toml;
+
+      CGO_ENABLED=0;
+
+      meta = with pkgs.lib; {
+        description = "A cloud-native LDAP server backed by a Consul datastore";
+        homepage = "https://git.deuxfleurs.fr/Deuxfleurs/bottin";
+        license = licenses.gpl3Plus;
+        platforms = platforms.linux;
+      };
+    };
+  in
+  {
+    packages.x86_64-linux.bottin = bottin;
+    packages.x86_64-linux.default = self.packages.x86_64-linux.bottin;
+  };
+}
--- a/go.mod
+++ b/go.mod
@ -3,9 +3,9 @@ module bottin
 go 1.13

 require (
-	github.com/go-ldap/ldap/v3 v3.3.0
 	github.com/google/uuid v1.1.1
 	github.com/hashicorp/consul/api v1.3.0
-	github.com/lor00x/goldap v0.0.0-20180618054307-a546dffdd1a3
+	github.com/jsimonetti/pwscheme v0.0.0-20220125093853-4d9895f5db73
 	github.com/sirupsen/logrus v1.4.2
+	golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9 // indirect
 )
--- a/go.sum
+++ b/go.sum
@ -1,5 +1,3 @@
-github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c h1:/IBSNwUN8+eKzUzbJPqhK839ygXJ82sde8x3ogr6R28=
-github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c/go.mod h1:chxPXzSsl7ZWRAuOIE23GDNzjWuZquvFlgA8xmpunjU=
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
 github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da h1:8GUt8eRujhVEGZFFEjBj46YV4rDjvGrNxb0KMWYkL2I=
 github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da/go.mod h1:Q73ZrmVTwzkszR9V5SSuryQ31EELlFMUz1kKyl939pY=
@ -9,11 +7,6 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
-github.com/go-asn1-ber/asn1-ber v1.5.1 h1:pDbRAunXzIUXfx4CB2QJFv5IuPiuoW+sWvr/Us009o8=
-github.com/go-asn1-ber/asn1-ber v1.5.1/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
-github.com/go-ldap/ldap v2.5.1+incompatible h1:Opaoft5zMW8IU/VRULB0eGMBQ9P5buRvCW6sFTRmMn8=
-github.com/go-ldap/ldap/v3 v3.3.0 h1:lwx+SJpgOHd8tG6SumBQZXCmNX51zM8B1cfxJ5gv4tQ=
-github.com/go-ldap/ldap/v3 v3.3.0/go.mod h1:iYS1MdmrmceOJ1QOTnRXrIs7i3kloqtmGQjRvjKpyMg=
 github.com/google/btree v0.0.0-20180813153112-4030bb1f1f0c h1:964Od4U6p2jUkFxvCydnIczKteheJEzHRToSGK3Bnlw=
 github.com/google/btree v0.0.0-20180813153112-4030bb1f1f0c/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/uuid v1.1.1 h1:Gkbcsh/GbpXz7lPftLA3P6TYMwjCLYm83jiFQZF/3gY=
@ -49,10 +42,10 @@ github.com/hashicorp/memberlist v0.1.3 h1:EmmoJme1matNzb+hMpDuR/0sbJSUisxyqBGG67
 github.com/hashicorp/memberlist v0.1.3/go.mod h1:ajVTdAv/9Im8oMAAj5G31PhhMCZJV2pPBoIllUwCN7I=
 github.com/hashicorp/serf v0.8.2 h1:YZ7UKsJv+hKjqGVUUbtE3HNj79Eln2oQ75tniF6iPt0=
 github.com/hashicorp/serf v0.8.2/go.mod h1:6hOLApaqBFA1NXqRQAsxw9QxuDEvNxSQRwA/JwenrHc=
+github.com/jsimonetti/pwscheme v0.0.0-20220125093853-4d9895f5db73 h1:ZhC4QngptYaGx53+ph1RjxcH8fkCozBaY+935TNX4i8=
+github.com/jsimonetti/pwscheme v0.0.0-20220125093853-4d9895f5db73/go.mod h1:t0Q9JvoMTfTYdAWIk2MF69iz+Qpdk9D+PgVu6fVmaDI=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
-github.com/lor00x/goldap v0.0.0-20180618054307-a546dffdd1a3 h1:wIONC+HMNRqmWBjuMxhatuSzHaljStc4gjDeKycxy0A=
-github.com/lor00x/goldap v0.0.0-20180618054307-a546dffdd1a3/go.mod h1:37YR9jabpiIxsb8X9VCIx8qFOjTDIIrIHHODa8C4gz0=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
 github.com/miekg/dns v1.0.14 h1:9jZdLNd/P4+SfEJ0TNyxYpsK8N4GtfylBLqtbYN1sbA=
@ -84,14 +77,13 @@ github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-golang.org/x/crypto v0.0.0-20181029021203-45a5f77698d3 h1:KYQXGkl6vs02hK7pK4eIbw0NpNPedieTSTEiJ//bwGs=
 golang.org/x/crypto v0.0.0-20181029021203-45a5f77698d3/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9 h1:vEg9joUBmeBcK9iSJftGNf3coIG4HqZElCPehJsfAYM=
 golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/net v0.0.0-20181023162649-9b4f9f5ad519/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
-golang.org/x/net v0.0.0-20181201002055-351d144fa1fc h1:a3CU5tJYVj92DY2LaA1kUkrsqD5/3mLDhx2NcNqyW+0=
 golang.org/x/net v0.0.0-20181201002055-351d144fa1fc/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 h1:0GoQqolDA55aaLxZyTzK/Y2ePZzZTUrRacwib7cNsYQ=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4 h1:YUO/7uOKsKeq9UokNS62b8FYywz3ker1l1vDZRCRefw=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
--- a/goldap/abandon_request.go
+++ b/goldap/abandon_request.go
@ -0,0 +1,25 @@
+package message
+
+import "fmt"
+
+//
+//        AbandonRequest ::= [APPLICATION 16] MessageID
+
+func readAbandonRequest(bytes *Bytes) (ret AbandonRequest, err error) {
+	var mes MessageID
+	mes, err = readTaggedMessageID(bytes, classApplication, TagAbandonRequest)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAbandonRequest:\n%s", err.Error())}
+		return
+	}
+	ret = AbandonRequest(mes)
+	return
+}
+
+func (abandon AbandonRequest) size() int {
+	return MessageID(abandon).sizeTagged(TagAbandonRequest)
+}
+
+func (abandon AbandonRequest) write(bytes *Bytes) int {
+	return MessageID(abandon).writeTagged(bytes, classApplication, TagAbandonRequest)
+}
--- a/goldap/add_request.go
+++ b/goldap/add_request.go
@ -0,0 +1,53 @@
+package message
+
+import "fmt"
+
+//
+//        AddRequest ::= [APPLICATION 8] SEQUENCE {
+//             entry           LDAPDN,
+//             attributes      AttributeList }
+
+func (add *AddRequest) Entry() LDAPDN {
+	return add.entry
+}
+
+func (add *AddRequest) Attributes() AttributeList {
+	return add.attributes
+}
+
+func readAddRequest(bytes *Bytes) (ret AddRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagAddRequest, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAddRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (add *AddRequest) readComponents(bytes *Bytes) (err error) {
+	add.entry, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	add.attributes, err = readAttributeList(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (add AddRequest) size() (size int) {
+	size += add.entry.size()
+	size += add.attributes.size()
+	size += sizeTagAndLength(TagAddRequest, size)
+	return
+}
+
+func (add AddRequest) write(bytes *Bytes) (size int) {
+	size += add.attributes.write(bytes)
+	size += add.entry.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagAddRequest, size)
+	return
+}
--- a/goldap/add_response.go
+++ b/goldap/add_response.go
@ -0,0 +1,28 @@
+package message
+
+import "fmt"
+
+//
+//        AddResponse ::= [APPLICATION 9] LDAPResult
+
+func (l *AddResponse) SetResultCode(code int) {
+	l.resultCode = ENUMERATED(code)
+}
+
+func readAddResponse(bytes *Bytes) (ret AddResponse, err error) {
+	var res LDAPResult
+	res, err = readTaggedLDAPResult(bytes, classApplication, TagAddResponse)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAddResponse:\n%s", err.Error())}
+		return
+	}
+	ret = AddResponse(res)
+	return
+}
+
+func (a AddResponse) size() int {
+	return LDAPResult(a).sizeTagged(TagAddResponse)
+}
+func (a AddResponse) write(bytes *Bytes) int {
+	return LDAPResult(a).writeTagged(bytes, classApplication, TagAddResponse)
+}
--- a/goldap/asn1.go
+++ b/goldap/asn1.go
@ -0,0 +1,760 @@
+package message
+
+// Below code is largely inspired from the standard golang library encoding/asn
+// If put BEGIN / END tags in the comments to give the original library name
+import (
+	//	"errors"
+	"fmt"
+	"math/big"
+	// "strconv"
+	// "time"
+)
+
+//
+// BEGIN: encoding/asn1/common.go
+//
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+const (
+	tagBoolean = 1
+	tagInteger = 2
+	// tagBitString   = 3
+	tagOctetString = 4
+	// tagOID         = 6
+	tagEnum = 10
+	// tagUTF8String = 12
+	tagSequence = 16
+	tagSet      = 17
+	// tagPrintableString = 19
+	// tagT61String       = 20
+	// tagIA5String       = 22
+	// tagUTCTime         = 23
+	// tagGeneralizedTime = 24
+	tagGeneralString = 27
+)
+
+var tagNames = map[int]string{
+	tagBoolean:     "BOOLEAN",
+	tagInteger:     "INTEGER",
+	tagOctetString: "OCTET STRING",
+	tagEnum:        "ENUM",
+	tagSequence: "SEQUENCE",
+	tagSet:      "SET",
+}
+
+const (
+	classUniversal       = 0
+	classApplication     = 1
+	classContextSpecific = 2
+	// classPrivate         = 3
+)
+
+var classNames = map[int]string{
+	classUniversal:       "UNIVERSAL",
+	classApplication:     "APPLICATION",
+	classContextSpecific: "CONTEXT SPECIFIC",
+}
+
+const (
+	isCompound    = true
+	isNotCompound = false
+)
+
+var compoundNames = map[bool]string{
+	isCompound:    "COMPOUND",
+	isNotCompound: "NOT COMPOUND",
+}
+
+type TagAndLength struct {
+	Class, Tag, Length int
+	IsCompound         bool
+}
+
+//
+// END: encoding/asn1/common.go
+//
+
+func (t *TagAndLength) Expect(class int, tag int, isCompound bool) (err error) {
+	err = t.ExpectClass(class)
+	if err != nil {
+		return LdapError{fmt.Sprintf("Expect: %s.", err)}
+	}
+	err = t.ExpectTag(tag)
+	if err != nil {
+		return LdapError{fmt.Sprintf("Expect: %s.", err)}
+	}
+	err = t.ExpectCompound(isCompound)
+	if err != nil {
+		return LdapError{fmt.Sprintf("Expect: %s.", err)}
+	}
+	return
+}
+func (t *TagAndLength) ExpectClass(class int) (err error) {
+	if class != t.Class {
+		err = SyntaxError{fmt.Sprintf("ExpectClass: wrong tag class: got %d (%s), expected %d (%s)", t.Class, classNames[t.Class], class, classNames[class])}
+	}
+	return
+}
+func (t *TagAndLength) ExpectTag(tag int) (err error) {
+	if tag != t.Tag {
+		err = SyntaxError{fmt.Sprintf("ExpectTag: wrong tag value: got %d (%s), expected %d (%s)", t.Tag, tagNames[t.Tag], tag, tagNames[tag])}
+	}
+	return
+}
+func (t *TagAndLength) ExpectCompound(isCompound bool) (err error) {
+	if isCompound != t.IsCompound {
+		err = SyntaxError{fmt.Sprintf("ExpectCompound: wrong tag compound: got %t (%s), expected %t (%s)", t.IsCompound, compoundNames[t.IsCompound], isCompound, compoundNames[isCompound])}
+	}
+	return
+}
+
+func ParseTagAndLength(bytes []byte, initOffset int) (ret TagAndLength, offset int, err error) {
+	ret, offset, err = parseTagAndLength(bytes, initOffset)
+	return
+}
+
+//
+// BEGIN encoding/asn1/asn1.go
+//
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package asn1 implements parsing of DER-encoded ASN.1 data structures,
+// as defined in ITU-T Rec X.690.
+//
+// See also ``A Layman's Guide to a Subset of ASN.1, BER, and DER,''
+// http://luca.ntop.org/Teaching/Appunti/asn1.html.
+// package asn1
+
+// ASN.1 is a syntax for specifying abstract objects and BER, DER, PER, XER etc
+// are different encoding formats for those objects. Here, we'll be dealing
+// with DER, the Distinguished Encoding Rules. DER is used in X.509 because
+// it's fast to parse and, unlike BER, has a unique encoding for every object.
+// When calculating hashes over objects, it's important that the resulting
+// bytes be the same at both ends and DER removes this margin of error.
+//
+// ASN.1 is very complex and this package doesn't attempt to implement
+// everything by any means.
+
+//import (
+//	"fmt"
+//	"math/big"
+//	"reflect"
+//	"strconv"
+//	"time"
+//)
+
+// A StructuralError suggests that the ASN.1 data is valid, but the Go type
+// which is receiving it doesn't match.
+type StructuralError struct {
+	Msg string
+}
+
+func (e StructuralError) Error() string { return "asn1: structure error: " + e.Msg }
+
+// A SyntaxError suggests that the ASN.1 data is invalid.
+type SyntaxError struct {
+	Msg string
+}
+
+func (e SyntaxError) Error() string { return "asn1: syntax error: " + e.Msg }
+
+// We start by dealing with each of the primitive types in turn.
+
+// BOOLEAN
+
+func parseBool(bytes []byte) (ret bool, err error) {
+	if len(bytes) > 1 {
+		err = SyntaxError{"invalid boolean: should be encoded on one byte only"}
+		return
+	} else if len(bytes) == 0 {
+		err = SyntaxError{"invalid boolean: no data to read"}
+	}
+
+	// DER demands that "If the encoding represents the boolean value TRUE,
+	// its single contents octet shall have all eight bits set to one."
+	// Thus only 0 and 255 are valid encoded values.
+	switch bytes[0] {
+	case 0:
+		ret = false
+	case 0xff:
+		ret = true
+	default:
+		err = SyntaxError{"invalid boolean: should be 0x00 of 0xFF"}
+	}
+
+	return
+}
+
+func sizeBool(b bool) int {
+	return 1
+}
+
+func writeBool(bytes *Bytes, b bool) int {
+	if b == false {
+		return bytes.writeBytes([]byte{0x00})
+	} else {
+		return bytes.writeBytes([]byte{0xff})
+	}
+}
+
+// INTEGER
+
+// parseInt64 treats the given bytes as a big-endian, signed integer and
+// returns the result.
+func parseInt64(bytes []byte) (ret int64, err error) {
+	if len(bytes) > 8 {
+		// We'll overflow an int64 in this case.
+		err = StructuralError{"integer too large"}
+		return
+	}
+	for bytesRead := 0; bytesRead < len(bytes); bytesRead++ {
+		ret <<= 8
+		ret |= int64(bytes[bytesRead])
+	}
+
+	// Shift up and down in order to sign extend the result.
+	ret <<= 64 - uint8(len(bytes))*8
+	ret >>= 64 - uint8(len(bytes))*8
+	return
+}
+
+func sizeInt64(i int64) int {
+	n := 1
+
+	for i > 127 {
+		n++
+		i >>= 8
+	}
+
+	for i < -128 {
+		n++
+		i >>= 8
+	}
+
+	return n
+}
+
+func writeInt64(bytes *Bytes, i int64) int {
+	n := sizeInt64(i)
+	buf := [8]byte{}
+
+	for j := 0; j < n; j++ {
+		b := i >> uint((n-1-j)*8)
+		buf[j] = byte(b)
+	}
+	bytes.writeBytes(buf[:n])
+
+	return n
+}
+
+// parseInt treats the given bytes as a big-endian, signed integer and returns
+// the result.
+func parseInt32(bytes []byte) (int32, error) {
+	ret64, err := parseInt64(bytes)
+	if err != nil {
+		return 0, err
+	}
+	if ret64 != int64(int32(ret64)) {
+		return 0, StructuralError{"integer too large"}
+	}
+	return int32(ret64), nil
+}
+
+func sizeInt32(i int32) int {
+	return sizeInt64(int64(i))
+}
+
+func writeInt32(bytes *Bytes, i int32) int {
+	return writeInt64(bytes, int64(i))
+}
+
+var bigOne = big.NewInt(1)
+
+// // parseBigInt treats the given bytes as a big-endian, signed integer and returns
+// // the result.
+// func parseBigInt(bytes []byte) *big.Int {
+// 	ret := new(big.Int)
+// 	if len(bytes) > 0 && bytes[0]&0x80 == 0x80 {
+// 		// This is a negative number.
+// 		notBytes := make([]byte, len(bytes))
+// 		for i := range notBytes {
+// 			notBytes[i] = ^bytes[i]
+// 		}
+// 		ret.SetBytes(notBytes)
+// 		ret.Add(ret, bigOne)
+// 		ret.Neg(ret)
+// 		return ret
+// 	}
+// 	ret.SetBytes(bytes)
+// 	return ret
+// }
+
+// // BIT STRING
+
+// // BitString is the structure to use when you want an ASN.1 BIT STRING type. A
+// // bit string is padded up to the nearest byte in memory and the number of
+// // valid bits is recorded. Padding bits will be zero.
+// type BitString struct {
+// 	Bytes     []byte // bits packed into bytes.
+// 	BitLength int    // length in bits.
+// }
+
+// // At returns the bit at the given index. If the index is out of range it
+// // returns false.
+// func (b BitString) At(i int) int {
+// 	if i < 0 || i >= b.BitLength {
+// 		return 0
+// 	}
+// 	x := i / 8
+// 	y := 7 - uint(i%8)
+// 	return int(b.Bytes[x]>>y) & 1
+// }
+
+// // RightAlign returns a slice where the padding bits are at the beginning. The
+// // slice may share memory with the BitString.
+// func (b BitString) RightAlign() []byte {
+// 	shift := uint(8 - (b.BitLength % 8))
+// 	if shift == 8 || len(b.Bytes) == 0 {
+// 		return b.Bytes
+// 	}
+
+// 	a := make([]byte, len(b.Bytes))
+// 	a[0] = b.Bytes[0] >> shift
+// 	for i := 1; i < len(b.Bytes); i++ {
+// 		a[i] = b.Bytes[i-1] << (8 - shift)
+// 		a[i] |= b.Bytes[i] >> shift
+// 	}
+
+// 	return a
+// }
+
+// // parseBitString parses an ASN.1 bit string from the given byte slice and returns it.
+// func parseBitString(bytes []byte) (ret BitString, err error) {
+// 	if len(bytes) == 0 {
+// 		err = SyntaxError{"zero length BIT STRING"}
+// 		return
+// 	}
+// 	paddingBits := int(bytes[0])
+// 	if paddingBits > 7 ||
+// 		len(bytes) == 1 && paddingBits > 0 ||
+// 		bytes[len(bytes)-1]&((1<<bytes[0])-1) != 0 {
+// 		err = SyntaxError{"invalid padding bits in BIT STRING"}
+// 		return
+// 	}
+// 	ret.BitLength = (len(bytes)-1)*8 - paddingBits
+// 	ret.Bytes = bytes[1:]
+// 	return
+// }
+
+// OBJECT IDENTIFIER
+
+// An ObjectIdentifier represents an ASN.1 OBJECT IDENTIFIER.
+// type ObjectIdentifier []int
+
+// // Equal reports whether oi and other represent the same identifier.
+// func (oi ObjectIdentifier) Equal(other ObjectIdentifier) bool {
+// 	if len(oi) != len(other) {
+// 		return false
+// 	}
+// 	for i := 0; i < len(oi); i++ {
+// 		if oi[i] != other[i] {
+// 			return false
+// 		}
+// 	}
+
+// 	return true
+// }
+
+// func (oi ObjectIdentifier) String() string {
+// 	var s string
+
+// 	for i, v := range oi {
+// 		if i > 0 {
+// 			s += "."
+// 		}
+// 		s += strconv.Itoa(v)
+// 	}
+
+// 	return s
+// }
+
+// // parseObjectIdentifier parses an OBJECT IDENTIFIER from the given bytes and
+// // returns it. An object identifier is a sequence of variable length integers
+// // that are assigned in a hierarchy.
+// func parseObjectIdentifier(bytes []byte) (s []int, err error) {
+// 	if len(bytes) == 0 {
+// 		err = SyntaxError{"zero length OBJECT IDENTIFIER"}
+// 		return
+// 	}
+
+// 	// In the worst case, we get two elements from the first byte (which is
+// 	// encoded differently) and then every varint is a single byte long.
+// 	s = make([]int, len(bytes)+1)
+
+// 	// The first varint is 40*value1 + value2:
+// 	// According to this packing, value1 can take the values 0, 1 and 2 only.
+// 	// When value1 = 0 or value1 = 1, then value2 is <= 39. When value1 = 2,
+// 	// then there are no restrictions on value2.
+// 	v, offset, err := parseBase128Int(bytes, 0)
+// 	if err != nil {
+// 		return
+// 	}
+// 	if v < 80 {
+// 		s[0] = v / 40
+// 		s[1] = v % 40
+// 	} else {
+// 		s[0] = 2
+// 		s[1] = v - 80
+// 	}
+
+// 	i := 2
+// 	for ; offset < len(bytes); i++ {
+// 		v, offset, err = parseBase128Int(bytes, offset)
+// 		if err != nil {
+// 			return
+// 		}
+// 		s[i] = v
+// 	}
+// 	s = s[0:i]
+// 	return
+// }
+
+// ENUMERATED
+
+// An Enumerated is represented as a plain int.
+type Enumerated int
+
+// FLAG
+
+// A Flag accepts any data and is set to true if present.
+type Flag bool
+
+// parseBase128Int parses a base-128 encoded int from the given offset in the
+// given byte slice. It returns the value and the new offset.
+func parseBase128Int(bytes []byte, initOffset int) (ret, offset int, err error) {
+	offset = initOffset
+	for shifted := 0; offset < len(bytes); shifted++ {
+		if shifted > 4 {
+			err = StructuralError{"base 128 integer too large"}
+			return
+		}
+		ret <<= 7
+		b := bytes[offset]
+		ret |= int(b & 0x7f)
+		offset++
+		if b&0x80 == 0 {
+			return
+		}
+	}
+	err = SyntaxError{"truncated base 128 integer"}
+	return
+}
+
+func sizeBase128Int(value int) (size int) {
+	for i := value; i > 0; i >>= 7 {
+		size++
+	}
+	return
+}
+
+// Write start as the end of the slice and goes back
+// We assume we have enough size
+func writeBase128Int(bytes *Bytes, value int) (size int) {
+	for ; value > 0 || size == 0; value >>= 7 { // Write at least one byte even if the value is 0
+		// Get the 7 lowest bits
+		b := byte(value) & 0x7f
+		if value < 128 {
+			b |= 0x80
+		}
+		bytes.writeBytes([]byte{b})
+		size++
+	}
+	return
+}
+
+// // UTCTime
+
+// func parseUTCTime(bytes []byte) (ret time.Time, err error) {
+// 	s := string(bytes)
+// 	ret, err = time.Parse("0601021504Z0700", s)
+// 	if err != nil {
+// 		ret, err = time.Parse("060102150405Z0700", s)
+// 	}
+// 	if err == nil && ret.Year() >= 2050 {
+// 		// UTCTime only encodes times prior to 2050. See https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1
+// 		ret = ret.AddDate(-100, 0, 0)
+// 	}
+
+// 	return
+// }
+
+// // parseGeneralizedTime parses the GeneralizedTime from the given byte slice
+// // and returns the resulting time.
+// func parseGeneralizedTime(bytes []byte) (ret time.Time, err error) {
+// 	return time.Parse("20060102150405Z0700", string(bytes))
+// }
+
+// // PrintableString
+
+// // parsePrintableString parses a ASN.1 PrintableString from the given byte
+// // array and returns it.
+// func parsePrintableString(bytes []byte) (ret string, err error) {
+// 	for _, b := range bytes {
+// 		if !isPrintable(b) {
+// 			err = SyntaxError{"PrintableString contains invalid character"}
+// 			return
+// 		}
+// 	}
+// 	ret = string(bytes)
+// 	return
+// }
+
+// // isPrintable returns true iff the given b is in the ASN.1 PrintableString set.
+// func isPrintable(b byte) bool {
+// 	return 'a' <= b && b <= 'z' ||
+// 		'A' <= b && b <= 'Z' ||
+// 		'0' <= b && b <= '9' ||
+// 		'\'' <= b && b <= ')' ||
+// 		'+' <= b && b <= '/' ||
+// 		b == ' ' ||
+// 		b == ':' ||
+// 		b == '=' ||
+// 		b == '?' ||
+// 		// This is technically not allowed in a PrintableString.
+// 		// However, x509 certificates with wildcard strings don't
+// 		// always use the correct string type so we permit it.
+// 		b == '*'
+// }
+
+// // IA5String
+
+// // parseIA5String parses a ASN.1 IA5String (ASCII string) from the given
+// // byte slice and returns it.
+// func parseIA5String(bytes []byte) (ret string, err error) {
+// 	for _, b := range bytes {
+// 		if b >= 0x80 {
+// 			err = SyntaxError{"IA5String contains invalid character"}
+// 			return
+// 		}
+// 	}
+// 	ret = string(bytes)
+// 	return
+// }
+
+// // T61String
+
+// // parseT61String parses a ASN.1 T61String (8-bit clean string) from the given
+// // byte slice and returns it.
+// func parseT61String(bytes []byte) (ret string, err error) {
+// 	return string(bytes), nil
+// }
+
+// UTF8String
+
+// parseUTF8String parses a ASN.1 UTF8String (raw UTF-8) from the given byte
+// array and returns it.
+// func parseUTF8String(bytes []byte) (ret string, err error) {
+// 	return string(bytes), nil
+// }
+// func sizeUTF8String(s string) int {
+// 	return len(s)
+// }
+// func writeUTF8String(bytes *Bytes, s string) int {
+// 	return bytes.writeString(s)
+// }
+
+// Octet string
+func parseOctetString(bytes []byte) (ret []byte, err error) {
+	return bytes, nil
+}
+func sizeOctetString(s []byte) int {
+	return len(s)
+}
+func writeOctetString(bytes *Bytes, s []byte) int {
+	return bytes.writeBytes(s)
+}
+
+// A RawValue represents an undecoded ASN.1 object.
+type RawValue struct {
+	Class, Tag int
+	IsCompound bool
+	Bytes      []byte
+	FullBytes  []byte // includes the tag and length
+}
+
+// RawContent is used to signal that the undecoded, DER data needs to be
+// preserved for a struct. To use it, the first field of the struct must have
+// this type. It's an error for any of the other fields to have this type.
+type RawContent []byte
+
+// Tagging
+
+// parseTagAndLength parses an ASN.1 tag and length pair from the given offset
+// into a byte slice. It returns the parsed data and the new offset. SET and
+// SET OF (tag 17) are mapped to SEQUENCE and SEQUENCE OF (tag 16) since we
+// don't distinguish between ordered and unordered objects in this code.
+func parseTagAndLength(bytes []byte, initOffset int) (ret TagAndLength, offset int, err error) {
+	offset = initOffset
+	b := bytes[offset]
+	offset++
+	ret.Class = int(b >> 6)
+	ret.IsCompound = b&0x20 == 0x20
+	ret.Tag = int(b & 0x1f)
+
+	// If the bottom five bits are set, then the tag number is actually base 128
+	// encoded afterwards
+	if ret.Tag == 0x1f {
+		ret.Tag, offset, err = parseBase128Int(bytes, offset)
+		if err != nil {
+			return
+		}
+	}
+	if offset >= len(bytes) {
+		err = SyntaxError{"truncated tag or length"}
+		return
+	}
+	b = bytes[offset]
+	offset++
+	if b&0x80 == 0 {
+		// The length is encoded in the bottom 7 bits.
+		ret.Length = int(b & 0x7f)
+	} else {
+		// Bottom 7 bits give the number of length bytes to follow.
+		numBytes := int(b & 0x7f)
+		if numBytes == 0 {
+			err = SyntaxError{"indefinite length found (not DER)"}
+			return
+		}
+		ret.Length = 0
+		for i := 0; i < numBytes; i++ {
+			if offset >= len(bytes) {
+				err = SyntaxError{"truncated tag or length"}
+				return
+			}
+			b = bytes[offset]
+			offset++
+			if ret.Length >= 1<<23 {
+				// We can't shift ret.length up without
+				// overflowing.
+				err = StructuralError{"length too large"}
+				return
+			}
+			ret.Length <<= 8
+			ret.Length |= int(b)
+			if ret.Length == 0 {
+				// DER requires that lengths be minimal.
+				err = StructuralError{"superfluous leading zeros in length"}
+				return
+			}
+		}
+	}
+
+	return
+}
+
+// func writeTagAndLength(out *forkableWriter, t tagAndLength) (err error) {
+// 	b := uint8(t.class) << 6
+// 	if t.isCompound {
+// 		b |= 0x20
+// 	}
+// 	if t.tag >= 31 {
+// 		b |= 0x1f
+// 		err = out.WriteByte(b)
+// 		if err != nil {
+// 			return
+// 		}
+// 		err = marshalBase128Int(out, int64(t.tag))
+// 		if err != nil {
+// 			return
+// 		}
+// 	} else {
+// 		b |= uint8(t.tag)
+// 		err = out.WriteByte(b)
+// 		if err != nil {
+// 			return
+// 		}
+// 	}
+
+// 	if t.length >= 128 {
+// 		l := lengthLength(t.length)
+// 		err = out.WriteByte(0x80 | byte(l))
+// 		if err != nil {
+// 			return
+// 		}
+// 		err = marshalLength(out, t.length)
+// 		if err != nil {
+// 			return
+// 		}
+// 	} else {
+// 		err = out.WriteByte(byte(t.length))
+// 		if err != nil {
+// 			return
+// 		}
+// 	}
+
+// 	return nil
+// }
+
+func sizeTagAndLength(tag int, length int) (size int) {
+	// Compute the size of the tag
+	size = 1
+	if tag >= 31 {
+		// Long-form identifier if the tag is greater than 30
+		// http://en.wikipedia.org/wiki/X.690#Identifier_tags_greater_than_30
+		size += sizeBase128Int(tag)
+	}
+	// Compute the size of the length using the definite form
+	// http://en.wikipedia.org/wiki/X.690#The_definite_form
+	size += 1
+	if length >= 128 {
+		size += 1
+		for length > 255 {
+			size++
+			length >>= 8
+		}
+	}
+	return
+}
+
+func writeTagAndLength(bytes *Bytes, t TagAndLength) (size int) {
+	// We are writing backward, so write the length bytes first
+	if t.Length < 0 {
+		panic("Can't have a negative length")
+
+	} else if t.Length >= 128 {
+		lengthBytes := 0
+		val := t.Length
+		for val > 0 {
+			lengthBytes++
+			bytes.writeBytes([]byte{byte(val & 0xff)})
+			val >>= 8
+		}
+		bytes.writeBytes([]byte{byte(0x80 | byte(lengthBytes))})
+		size += lengthBytes + 1
+
+	} else if t.Length < 128 {
+		size += bytes.writeBytes([]byte{byte(t.Length)})
+	}
+	// Then write the tag
+	b := uint8(t.Class) << 6
+	if t.IsCompound {
+		b |= 0x20
+	}
+	if t.Tag >= 31 {
+		b |= 0x1f
+		size += writeBase128Int(bytes, t.Tag)
+	} else {
+		b |= uint8(t.Tag)
+	}
+	size += bytes.writeBytes([]byte{byte(b)})
+	return
+}
+
+//
+// END encoding/asn1/asn1.go
+//
--- a/goldap/asn1_test.go
+++ b/goldap/asn1_test.go
@ -0,0 +1,54 @@
+package message
+
+import (
+  "testing"
+  "bytes"
+)
+
+func TestSizeInt64(t *testing.T) {
+  s := sizeInt64(0)
+  if s != 1 {
+    t.Errorf("computed size is %d, expected 1", s)
+  }
+
+  s = sizeInt64(127)
+  if s != 1 {
+    t.Errorf("computed size is %d, expected 1", s)
+  }
+
+  s = sizeInt64(128)
+  if s != 2 {
+    t.Errorf("computed size is %d, expected 2", s)
+  }
+
+  s = sizeInt64(50000)
+  if s != 3 {
+    t.Errorf("computed size is %d, expected 3", s)
+  }
+
+  s = sizeInt64(-12345)
+  if s != 2 {
+    t.Errorf("computed size is %d, expected 2", s)
+  }
+}
+
+func TestWriteInt64(t *testing.T) {
+  vtests := []int64{0, 127, 128, 50000, -12345}
+  expsize := []int{1, 1, 2, 3, 2}
+  expresult := [][]byte{{0x00}, {0x7F}, {0x00, 0x80}, {0x00, 0xc3, 0x50}, {0xcf, 0xc7}}
+
+  for idx, v := range vtests {
+    fs := sizeInt64(v)
+    b := NewBytes(fs, make([]byte, fs))
+    t.Log("computing", v)
+    s := writeInt64(b, v)
+    if s != expsize[idx] {
+      t.Errorf("computed size is %d, expected %d", s, expsize[idx])
+    }
+    if !bytes.Equal(b.Bytes(), expresult[idx]) {
+      t.Errorf("wrong computed bytes, got %v, expected %v", b.Bytes(), expresult[idx])
+    }
+    a, e := parseInt64(b.Bytes())
+    t.Log("parse", a, e)
+  }
+}
--- a/goldap/assertion_value.go
+++ b/goldap/assertion_value.go
@ -0,0 +1,44 @@
+package message
+
+import "fmt"
+
+//
+//        AssertionValue ::= OCTET STRING
+
+func readAssertionValue(bytes *Bytes) (assertionvalue AssertionValue, err error) {
+	var octetstring OCTETSTRING
+	octetstring, err = readOCTETSTRING(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAssertionValue:\n%s", err.Error())}
+		return
+	}
+	assertionvalue = AssertionValue(octetstring)
+	return
+}
+
+func readTaggedAssertionValue(bytes *Bytes, class int, tag int) (assertionvalue AssertionValue, err error) {
+	var octetstring OCTETSTRING
+	octetstring, err = readTaggedOCTETSTRING(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedAssertionValue:\n%s", err.Error())}
+		return
+	}
+	assertionvalue = AssertionValue(octetstring)
+	return
+}
+
+func (assertion AssertionValue) size() int {
+	return OCTETSTRING(assertion).size()
+}
+
+func (assertion AssertionValue) sizeTagged(tag int) int {
+	return OCTETSTRING(assertion).sizeTagged(tag)
+}
+
+func (assertion AssertionValue) write(bytes *Bytes) int {
+	return OCTETSTRING(assertion).write(bytes)
+}
+
+func (assertion AssertionValue) writeTagged(bytes *Bytes, class int, tag int) int {
+	return OCTETSTRING(assertion).writeTagged(bytes, class, tag)
+}
--- a/goldap/attribute.go
+++ b/goldap/attribute.go
@ -0,0 +1,40 @@
+package message
+
+import "fmt"
+
+//
+//        Attribute ::= PartialAttribute(WITH COMPONENTS {
+//             ...,
+//             vals (SIZE(1..MAX))})
+
+func (attribute *Attribute) Type_() AttributeDescription {
+	return attribute.type_
+}
+
+func (attribute *Attribute) Vals() []AttributeValue {
+	return attribute.vals
+}
+
+func readAttribute(bytes *Bytes) (ret Attribute, err error) {
+	var par PartialAttribute
+	par, err = readPartialAttribute(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAttribute:\n%s", err.Error())}
+		return
+	}
+	if len(par.vals) == 0 {
+		err = LdapError{"readAttribute: expecting at least one value"}
+		return
+	}
+	ret = Attribute(par)
+	return
+
+}
+
+func (attribute Attribute) size() (size int) {
+	return PartialAttribute(attribute).size()
+}
+
+func (attribute Attribute) write(bytes *Bytes) (size int) {
+	return PartialAttribute(attribute).write(bytes)
+}
--- a/goldap/attribute_description.go
+++ b/goldap/attribute_description.go
@ -0,0 +1,50 @@
+package message
+
+import "fmt"
+
+//
+//        AttributeDescription ::= LDAPString
+//                                -- Constrained to <attributedescription>
+//                                -- [RFC4512]
+
+func (description AttributeDescription) Pointer() *AttributeDescription { return &description }
+
+func readAttributeDescription(bytes *Bytes) (ret AttributeDescription, err error) {
+	var ldapstring LDAPString
+	ldapstring, err = readLDAPString(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAttributeDescription:\n%s", err.Error())}
+		return
+	}
+	// @TODO: check RFC4512
+	ret = AttributeDescription(ldapstring)
+	return
+}
+
+func readTaggedAttributeDescription(bytes *Bytes, class int, tag int) (ret AttributeDescription, err error) {
+	var ldapstring LDAPString
+	ldapstring, err = readTaggedLDAPString(bytes, class, tag)
+	// @TODO: check RFC4512
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedAttributeDescription:\n%s", err.Error())}
+		return
+	}
+	ret = AttributeDescription(ldapstring)
+	return
+}
+
+func (description AttributeDescription) size() int {
+	return LDAPString(description).size()
+}
+
+func (description AttributeDescription) sizeTagged(tag int) int {
+	return LDAPString(description).sizeTagged(tag)
+}
+
+func (description AttributeDescription) write(bytes *Bytes) int {
+	return LDAPString(description).write(bytes)
+}
+
+func (description AttributeDescription) writeTagged(bytes *Bytes, class int, tag int) int {
+	return LDAPString(description).writeTagged(bytes, class, tag)
+}
--- a/goldap/attribute_list.go
+++ b/goldap/attribute_list.go
@ -0,0 +1,43 @@
+package message
+
+import "fmt"
+
+//
+//        AttributeList ::= SEQUENCE OF attribute Attribute
+
+func readAttributeList(bytes *Bytes) (ret AttributeList, err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAttributeList:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (list *AttributeList) readComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var attr Attribute
+		attr, err = readAttribute(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		*list = append(*list, attr)
+	}
+	return
+}
+
+func (list AttributeList) size() (size int) {
+	for _, att := range list {
+		size += att.size()
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+
+func (list AttributeList) write(bytes *Bytes) (size int) {
+	for i := len(list) - 1; i >= 0; i-- {
+		size += list[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
--- a/goldap/attribute_selection.go
+++ b/goldap/attribute_selection.go
@ -0,0 +1,46 @@
+package message
+
+import "fmt"
+
+//
+//        AttributeSelection ::= SEQUENCE OF selector LDAPString
+//                       -- The LDAPString is constrained to
+//                       -- <attributeSelector> in Section 4.5.1.8
+
+func readAttributeSelection(bytes *Bytes) (attributeSelection AttributeSelection, err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, attributeSelection.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAttributeSelection:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (selection *AttributeSelection) readComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var ldapstring LDAPString
+		ldapstring, err = readLDAPString(bytes)
+		// @TOTO: check <attributeSelector> in Section 4.5.1.8
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		*selection = append(*selection, ldapstring)
+	}
+	return
+}
+
+func (selection AttributeSelection) write(bytes *Bytes) (size int) {
+	for i := len(selection) - 1; i >= 0; i-- {
+		size += selection[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+
+func (selection AttributeSelection) size() (size int) {
+	for _, selector := range selection {
+		size += selector.size()
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
--- a/goldap/attribute_value.go
+++ b/goldap/attribute_value.go
@ -0,0 +1,24 @@
+package message
+
+import "fmt"
+
+//
+//        AttributeValue ::= OCTET STRING
+
+func readAttributeValue(bytes *Bytes) (ret AttributeValue, err error) {
+	octetstring, err := readOCTETSTRING(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAttributeValue:\n%s", err.Error())}
+		return
+	}
+	ret = AttributeValue(octetstring)
+	return
+}
+
+func (value AttributeValue) write(bytes *Bytes) int {
+	return OCTETSTRING(value).write(bytes)
+}
+
+func (value AttributeValue) size() int {
+	return OCTETSTRING(value).size()
+}
--- a/goldap/attribute_value_assertion.go
+++ b/goldap/attribute_value_assertion.go
@ -0,0 +1,77 @@
+package message
+
+import "fmt"
+
+//
+//        AttributeValueAssertion ::= SEQUENCE {
+//             attributeDesc   AttributeDescription,
+//             assertionValue  AssertionValue }
+
+func (assertion *AttributeValueAssertion) AttributeDesc() AttributeDescription {
+	return assertion.attributeDesc
+}
+
+func (assertion *AttributeValueAssertion) AssertionValue() AssertionValue {
+	return assertion.assertionValue
+}
+
+func readAttributeValueAssertion(bytes *Bytes) (ret AttributeValueAssertion, err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAttributeValueAssertion:\n%s", err.Error())}
+		return
+	}
+	return
+
+}
+
+func readTaggedAttributeValueAssertion(bytes *Bytes, class int, tag int) (ret AttributeValueAssertion, err error) {
+	err = bytes.ReadSubBytes(class, tag, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedAttributeValueAssertion:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (assertion *AttributeValueAssertion) readComponents(bytes *Bytes) (err error) {
+	assertion.attributeDesc, err = readAttributeDescription(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	assertion.assertionValue, err = readAssertionValue(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (assertion AttributeValueAssertion) write(bytes *Bytes) (size int) {
+	size += assertion.assertionValue.write(bytes)
+	size += assertion.attributeDesc.write(bytes)
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+
+func (assertion AttributeValueAssertion) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	size += assertion.assertionValue.write(bytes)
+	size += assertion.attributeDesc.write(bytes)
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+func (assertion AttributeValueAssertion) size() (size int) {
+	size += assertion.attributeDesc.size()
+	size += assertion.assertionValue.size()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+
+func (assertion AttributeValueAssertion) sizeTagged(tag int) (size int) {
+	size += assertion.attributeDesc.size()
+	size += assertion.assertionValue.size()
+	size += sizeTagAndLength(tag, size)
+	return
+}
--- a/goldap/authentication_choice.go
+++ b/goldap/authentication_choice.go
@ -0,0 +1,37 @@
+package message
+
+import "fmt"
+
+//
+//        AuthenticationChoice ::= CHOICE {
+//             simple                  [0] OCTET STRING,
+//                                     -- 1 and 2 reserved
+//             sasl                    [3] SaslCredentials,
+//             ...  }
+
+func readAuthenticationChoice(bytes *Bytes) (ret AuthenticationChoice, err error) {
+	tagAndLength, err := bytes.PreviewTagAndLength()
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAuthenticationChoice:\n%s", err.Error())}
+		return
+	}
+	err = tagAndLength.ExpectClass(classContextSpecific)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAuthenticationChoice:\n%s", err.Error())}
+		return
+	}
+	switch tagAndLength.Tag {
+	case TagAuthenticationChoiceSimple:
+		ret, err = readTaggedOCTETSTRING(bytes, classContextSpecific, TagAuthenticationChoiceSimple)
+	case TagAuthenticationChoiceSaslCredentials:
+		ret, err = readSaslCredentials(bytes)
+	default:
+		err = LdapError{fmt.Sprintf("readAuthenticationChoice: invalid tag value %d for AuthenticationChoice", tagAndLength.Tag)}
+		return
+	}
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readAuthenticationChoice:\n%s", err.Error())}
+		return
+	}
+	return
+}
--- a/goldap/bind_request.go
+++ b/goldap/bind_request.go
@ -0,0 +1,93 @@
+package message
+
+import "fmt"
+
+//        BindRequest ::= [APPLICATION 0] SEQUENCE {
+//             version                 INTEGER (1 ..  127),
+//             name                    LDAPDN,
+//             authentication          AuthenticationChoice }
+
+func (request *BindRequest) Name() LDAPDN {
+	return request.name
+}
+
+func (request *BindRequest) Authentication() AuthenticationChoice {
+	return request.authentication
+}
+
+func (request *BindRequest) AuthenticationSimple() OCTETSTRING {
+	return request.Authentication().(OCTETSTRING)
+}
+
+func (request *BindRequest) AuthenticationChoice() string {
+	switch request.Authentication().(type) {
+	case OCTETSTRING:
+		return "simple"
+	case SaslCredentials:
+		return "sasl"
+	}
+	return ""
+}
+
+func readBindRequest(bytes *Bytes) (bindrequest BindRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagBindRequest, bindrequest.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readBindRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (request *BindRequest) readComponents(bytes *Bytes) (err error) {
+	request.version, err = readINTEGER(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if !(request.version >= BindRequestVersionMin && request.version <= BindRequestVersionMax) {
+		err = LdapError{fmt.Sprintf("readComponents: invalid version %d, must be between %d and %d", request.version, BindRequestVersionMin, BindRequestVersionMax)}
+		return
+	}
+	request.name, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	request.authentication, err = readAuthenticationChoice(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (request BindRequest) write(bytes *Bytes) (size int) {
+	switch request.authentication.(type) {
+	case OCTETSTRING:
+		size += request.authentication.(OCTETSTRING).writeTagged(bytes, classContextSpecific, TagAuthenticationChoiceSimple)
+	case SaslCredentials:
+		size += request.authentication.(SaslCredentials).writeTagged(bytes, classContextSpecific, TagAuthenticationChoiceSaslCredentials)
+	default:
+		panic(fmt.Sprintf("Unknown authentication choice: %#v", request.authentication))
+	}
+	size += request.name.write(bytes)
+	size += request.version.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagBindRequest, size)
+	return
+}
+
+func (request BindRequest) size() (size int) {
+	size += request.version.size()
+	size += request.name.size()
+	switch request.authentication.(type) {
+	case OCTETSTRING:
+		size += request.authentication.(OCTETSTRING).sizeTagged(TagAuthenticationChoiceSimple)
+	case SaslCredentials:
+		size += request.authentication.(SaslCredentials).sizeTagged(TagAuthenticationChoiceSaslCredentials)
+	default:
+		panic(fmt.Sprintf("Unknown authentication choice: %#v", request.authentication))
+	}
+
+	size += sizeTagAndLength(TagBindRequest, size)
+	return
+}
--- a/goldap/bind_response.go
+++ b/goldap/bind_response.go
@ -0,0 +1,56 @@
+package message
+
+import "fmt"
+
+//        BindResponse ::= [APPLICATION 1] SEQUENCE {
+//             COMPONENTS OF LDAPResult,
+//             serverSaslCreds    [7] OCTET STRING OPTIONAL }
+
+func readBindResponse(bytes *Bytes) (bindresponse BindResponse, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagBindResponse, bindresponse.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readBindResponse:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (response *BindResponse) readComponents(bytes *Bytes) (err error) {
+	response.LDAPResult.readComponents(bytes)
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagBindResponseServerSaslCreds {
+			var serverSaslCreds OCTETSTRING
+			serverSaslCreds, err = readTaggedOCTETSTRING(bytes, classContextSpecific, TagBindResponseServerSaslCreds)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			response.serverSaslCreds = serverSaslCreds.Pointer()
+		}
+	}
+	return
+}
+
+func (response BindResponse) write(bytes *Bytes) (size int) {
+	if response.serverSaslCreds != nil {
+		size += response.serverSaslCreds.writeTagged(bytes, classContextSpecific, TagBindResponseServerSaslCreds)
+	}
+	size += response.LDAPResult.writeComponents(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagBindResponse, size)
+	return
+}
+
+func (response BindResponse) size() (size int) {
+	if response.serverSaslCreds != nil {
+		size += response.serverSaslCreds.sizeTagged(TagBindResponseServerSaslCreds)
+	}
+	size += response.LDAPResult.sizeComponents()
+	size += sizeTagAndLength(TagBindResponse, size)
+	return
+}
--- a/goldap/boolean.go
+++ b/goldap/boolean.go
@ -0,0 +1,62 @@
+package message
+
+import "fmt"
+
+func readBOOLEAN(bytes *Bytes) (ret BOOLEAN, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(classUniversal, tagBoolean, tagBoolean)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readBOOLEAN:\n%s", err.Error())}
+		return
+	}
+	ret = BOOLEAN(value.(bool))
+	return
+}
+
+func (boolean BOOLEAN) write(bytes *Bytes) int {
+	return bytes.WritePrimitiveSubBytes(classUniversal, tagBoolean, boolean)
+}
+
+func (boolean BOOLEAN) writeTagged(bytes *Bytes, class int, tag int) int {
+	return bytes.WritePrimitiveSubBytes(class, tag, boolean)
+}
+
+func readTaggedBOOLEAN(bytes *Bytes, class int, tag int) (ret BOOLEAN, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(class, tag, tagBoolean)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedBOOLEAN:\n%s", err.Error())}
+		return
+	}
+	ret = BOOLEAN(value.(bool))
+	return
+}
+
+func SizePrimitiveSubBytes(tag int, value interface{}) (size int) {
+	switch value.(type) {
+	case BOOLEAN:
+		size = sizeBool(bool(value.(BOOLEAN)))
+	case INTEGER:
+		size = sizeInt32(int32(value.(INTEGER)))
+	case ENUMERATED:
+		size = sizeInt32(int32(value.(ENUMERATED)))
+	case OCTETSTRING:
+		size = sizeOctetString([]byte(string(value.(OCTETSTRING))))
+	default:
+		panic(fmt.Sprintf("SizePrimitiveSubBytes: invalid value type %v", value))
+	}
+	size += sizeTagAndLength(tag, size)
+	return
+}
+
+func (boolean BOOLEAN) size() int {
+	return SizePrimitiveSubBytes(tagBoolean, boolean)
+}
+
+func (boolean BOOLEAN) sizeTagged(tag int) int {
+	return SizePrimitiveSubBytes(tag, boolean)
+}
+
+func (boolean BOOLEAN) Bool() bool {
+	return bool(boolean)
+}
--- a/goldap/bytes.go
+++ b/goldap/bytes.go
@ -0,0 +1,199 @@
+package message
+
+import (
+	"fmt"
+)
+
+type Bytes struct {
+	offset int
+	bytes  []byte
+}
+
+func (bytes *Bytes) getBytes() []byte {
+	return bytes.bytes
+}
+func NewBytes(offset int, bytes []byte) (ret *Bytes) {
+	return &Bytes{offset: offset, bytes: bytes}
+}
+
+func (bytes Bytes) Debug() {
+	fmt.Printf("Offset: %d, Bytes: %+v\n", bytes.offset, bytes.bytes)
+}
+
+// Return a string with the hex dump of the bytes around the current offset
+// The current offset byte is put in brackets
+// Example: 0x01, [0x02], 0x03
+func (bytes *Bytes) DumpCurrentBytes() (ret string) {
+	var strings [3]string
+	for i := -1; i <= 1; i++ {
+		if bytes.offset+i >= 0 && bytes.offset+i < len(bytes.bytes) {
+			strings[i+1] = fmt.Sprintf("%#x", bytes.bytes[bytes.offset+i])
+		}
+	}
+	ret = fmt.Sprintf("%s, [%s], %s", strings[0], strings[1], strings[2])
+	return
+}
+
+func (bytes *Bytes) HasMoreData() bool {
+	return bytes.offset < len(bytes.bytes)
+}
+
+func (bytes *Bytes) ParseTagAndLength() (ret TagAndLength, err error) {
+	var offset int
+	ret, offset, err = ParseTagAndLength(bytes.bytes, bytes.offset)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("ParseTagAndLength: %s", err.Error())}
+		return
+	} else {
+		bytes.offset = offset
+	}
+	return
+}
+
+func (bytes *Bytes) ReadSubBytes(class int, tag int, callback func(bytes *Bytes) error) (err error) {
+	// Check tag
+	tagAndLength, err := bytes.ParseTagAndLength()
+	if err != nil {
+		return LdapError{fmt.Sprintf("ReadSubBytes:\n%s", err.Error())}
+	}
+	err = tagAndLength.Expect(class, tag, isCompound)
+	if err != nil {
+		return LdapError{fmt.Sprintf("ReadSubBytes:\n%s", err.Error())}
+	}
+
+	start := bytes.offset
+	end := bytes.offset + tagAndLength.Length
+
+	// Check we got enough bytes to process
+	if end > len(bytes.bytes) {
+		return LdapError{fmt.Sprintf("ReadSubBytes: data truncated: expecting %d bytes at offset %d", tagAndLength.Length, bytes.offset)}
+	}
+	// Process sub-bytes
+	subBytes := Bytes{offset: 0, bytes: bytes.bytes[start:end]}
+	err = callback(&subBytes)
+	if err != nil {
+		bytes.offset += subBytes.offset
+		err = LdapError{fmt.Sprintf("ReadSubBytes:\n%s", err.Error())}
+		return
+	}
+	// Check we got no more bytes to process
+	if subBytes.HasMoreData() {
+		return LdapError{fmt.Sprintf("ReadSubBytes: data too long: %d more bytes to read at offset %d", end-bytes.offset, bytes.offset)}
+	}
+	// Move offset
+	bytes.offset = end
+	return
+}
+
+func SizeSubBytes(tag int, callback func() int) (size int) {
+	size = callback()
+	size += sizeTagAndLength(tag, size)
+	return
+}
+
+func (bytes *Bytes) WritePrimitiveSubBytes(class int, tag int, value interface{}) (size int) {
+	switch value.(type) {
+	case BOOLEAN:
+		size = writeBool(bytes, bool(value.(BOOLEAN)))
+	case INTEGER:
+		size = writeInt32(bytes, int32(value.(INTEGER)))
+	case ENUMERATED:
+		size = writeInt32(bytes, int32(value.(ENUMERATED)))
+	case OCTETSTRING:
+		size = writeOctetString(bytes, []byte(string(value.(OCTETSTRING))))
+	default:
+		panic(fmt.Sprintf("WritePrimitiveSubBytes: invalid value type %v", value))
+	}
+	size += bytes.WriteTagAndLength(class, isNotCompound, tag, size)
+	return
+}
+
+func (bytes *Bytes) WriteTagAndLength(class int, compound bool, tag int, length int) int {
+	return writeTagAndLength(bytes, TagAndLength{Class: class, IsCompound: compound, Tag: tag, Length: length})
+}
+
+func (bytes *Bytes) writeString(s string) (size int) {
+	size = len(s)
+	start := bytes.offset - size
+	if start < 0 {
+		panic("Not enough space for string")
+	}
+	copy(bytes.bytes[start:], s)
+	bytes.offset = start
+	return
+}
+
+func (bytes *Bytes) writeBytes(b []byte) (size int) {
+	size = len(b)
+	start := bytes.offset - size
+	if start < 0 {
+		panic("Not enough space for bytes")
+	}
+	copy(bytes.bytes[start:], b)
+	bytes.offset = start
+	return
+}
+
+//
+// Parse tag, length and read the a primitive value
+// Supported types are:
+// - boolean
+// - integer (parsed as int32)
+// - enumerated (parsed as int32)
+// - UTF8 string
+// - Octet string
+//
+// Parameters:
+// - class: the expected class value(classUniversal, classApplication, classContextSpecific)
+// - tag: the expected tag value
+// - typeTag: the real primitive type to parse (tagBoolean, tagInteger, tagEnym, tagUTF8String, tagOctetString)
+//
+func (bytes *Bytes) ReadPrimitiveSubBytes(class int, tag int, typeTag int) (value interface{}, err error) {
+	// Check tag
+	tagAndLength, err := bytes.ParseTagAndLength()
+	if err != nil {
+		err = LdapError{fmt.Sprintf("ReadPrimitiveSubBytes:\n%s", err.Error())}
+		return
+	}
+	err = tagAndLength.Expect(class, tag, isNotCompound)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("ReadPrimitiveSubBytes:\n%s", err.Error())}
+		return
+	}
+
+	start := bytes.offset
+	end := bytes.offset + tagAndLength.Length
+
+	// Check we got enough bytes to process
+	if end > len(bytes.bytes) {
+		// err = LdapError{fmt.Sprintf("ReadPrimitiveSubBytes: data truncated: expecting %d bytes at offset %d but only %d bytes are remaining (start: %d, length: %d, end: %d, len(b): %d, bytes: %#+v)", tagAndLength.Length, *b.offset, len(b.bytes)-start, start, tagAndLength.Length, end, len(b.bytes), b.bytes)}
+		err = LdapError{fmt.Sprintf("ReadPrimitiveSubBytes: data truncated: expecting %d bytes at offset %d but only %d bytes are remaining", tagAndLength.Length, bytes.offset, len(bytes.bytes)-start)}
+		return
+	}
+	// Process sub-bytes
+	subBytes := bytes.bytes[start:end]
+	switch typeTag {
+	case tagBoolean:
+		value, err = parseBool(subBytes)
+	case tagInteger:
+		value, err = parseInt32(subBytes)
+	case tagEnum:
+		value, err = parseInt32(subBytes)
+	case tagOctetString:
+		value, err = parseOctetString(subBytes)
+	default:
+		err = LdapError{fmt.Sprintf("ReadPrimitiveSubBytes: invalid type tag value %d", typeTag)}
+		return
+	}
+	if err != nil {
+		err = LdapError{fmt.Sprintf("ReadPrimitiveSubBytes:\n%s", err.Error())}
+		return
+	}
+	// Move offset
+	bytes.offset = end
+	return
+}
+
+func (bytes *Bytes) Bytes() []byte {
+	return bytes.bytes
+}
--- a/goldap/bytes_test.go
+++ b/goldap/bytes_test.go
@ -0,0 +1,172 @@
+package message
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestReadPrimitiveSubBytesTestData(t *testing.T) {
+	for i, test := range PrimitiveSubBytesTestData() {
+		value, err := test.bytes.ReadPrimitiveSubBytes(test.class, test.tag, test.typeTag)
+		if err != nil {
+			t.Errorf("#%d failed: %s", i+1, err)
+		} else if !reflect.DeepEqual(test.value, value) {
+			t.Errorf("#%d: Wrong value %#v, got %#v", i+1, test.value, value)
+		} else if test.offset != test.bytes.offset {
+			t.Errorf("#%d: Wrong Offset, value %#v, got %#v", i+1, test.offset, test.bytes.offset)
+		}
+	}
+}
+
+func TestSizePrimitiveSubBytesTestData(t *testing.T) {
+	for i, test := range PrimitiveSubBytesTestData() {
+		value, err := test.bytes.ReadPrimitiveSubBytes(test.class, test.tag, test.typeTag)
+		if err != nil {
+			t.Errorf("#%d failed: %s", i+1, err)
+		} else if !reflect.DeepEqual(test.value, value) {
+			t.Errorf("#%d: Wrong value %#v, got %#v", i+1, test.value, value)
+		} else if test.offset != test.bytes.offset {
+			t.Errorf("#%d: Wrong Offset, value %#v, got %#v", i+1, test.offset, test.bytes.offset)
+		}
+	}
+}
+
+func NewInt(value int) (ret *int) {
+	ret = &value
+	return
+}
+
+type PrimitiveSubBytesTestSingleData struct {
+	bytes   Bytes       // Input
+	class   int         // Expected class
+	tag     int         // Expected tag
+	typeTag int         // Expected type
+	value   interface{} // Expected output
+	offset  int         // Expected offset after processing
+}
+
+func PrimitiveSubBytesTestData() []PrimitiveSubBytesTestSingleData {
+
+	return []PrimitiveSubBytesTestSingleData{
+		// Test 1
+		{
+			bytes: Bytes{
+				offset: 0,
+				bytes:  []byte{0x02, 0x01, 0x09},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x09),
+			offset:  3,
+		},
+		// Test 2
+		{
+			bytes: Bytes{
+				offset: 0,
+				bytes:  []byte{0x02, 0x02, 0x09, 0x87},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x0987),
+			offset:  4,
+		},
+		// Test 3
+		{
+			bytes: Bytes{
+				offset: 0,
+				bytes:  []byte{0x02, 0x03, 0x09, 0x87, 0x65},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x098765),
+			offset:  5,
+		},
+		// Test 4
+		{
+			bytes: Bytes{
+				offset: 0,
+				bytes:  []byte{0x02, 0x04, 0x09, 0x87, 0x65, 0x43},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x09876543),
+			offset:  6,
+		},
+		// Test 5
+		{
+			bytes: Bytes{
+				offset: 2,
+				bytes:  []byte{0x30, 0x03, 0x02, 0x01, 0x0f},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x0f),
+			offset:  5,
+		},
+		// Test 6
+		{
+			bytes: Bytes{
+				offset: 2,
+				bytes:  []byte{0x30, 0x16, 0x02, 0x01, 0x0f, 0x60, 0x11, 0x02, 0x01, 0x03, 0x04, 0x00, 0xa3, 0x0a, 0x04, 0x08, 0x43, 0x52, 0x41, 0x4d, 0x2d, 0x4d, 0x44, 0x35},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x0f),
+			offset:  5,
+		},
+		// Test 7
+		{
+			bytes: Bytes{
+				offset: 2,
+				bytes:  []byte{0x30, 0x19, 0x02, 0x04, 0x7f, 0xff, 0xff, 0xff, 0x60, 0x11, 0x02, 0x01, 0x03, 0x04, 0x00, 0xa3, 0x0a, 0x04, 0x08, 0x43, 0x52, 0x41, 0x4d, 0x2d, 0x4d, 0x44, 0x35},
+			},
+			class:   classUniversal,
+			tag:     tagInteger,
+			typeTag: tagInteger,
+			value:   int32(0x07fffffff),
+			offset:  8,
+		},
+		// Test 8
+		{
+			bytes: Bytes{
+				offset: 0,
+				bytes:  []byte{0x04, 0x08, 0x43, 0x52, 0x41, 0x4d, 0x2d, 0x4d, 0x44, 0x35},
+			},
+			class:   classUniversal,
+			tag:     tagOctetString,
+			typeTag: tagOctetString,
+			value:   []byte("CRAM-MD5"),
+			offset:  10,
+		},
+		// Test 9
+		{
+			bytes: Bytes{
+				offset: 0,
+				bytes:  []byte{0x04, 0x0d, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x2c, 0x20, 0xe4, 0xb8, 0x96, 0xe7, 0x95, 0x8c},
+			},
+			class:   classUniversal,
+			tag:     tagOctetString,
+			typeTag: tagOctetString,
+			value:   []byte("Hello, 世界"),
+			offset:  15,
+		},
+		// Test 10
+		{
+			bytes: Bytes{
+				offset: 10,
+				bytes:  []byte{0x30, 0x1d, 0x02, 0x01, 0x05, 0x60, 0x18, 0x02, 0x01, 0x03, 0x04, 0x07, 0x6d, 0x79, 0x4c, 0x6f, 0x67, 0x69, 0x6e, 0x80, 0x0a, 0x6d, 0x79, 0x50, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64},
+			},
+			class:   classUniversal,
+			tag:     tagOctetString,
+			typeTag: tagOctetString,
+			value:   []byte("myLogin"),
+			offset:  19,
+		},
+	}
+}
--- a/goldap/compare_request.go
+++ b/goldap/compare_request.go
@ -0,0 +1,53 @@
+package message
+
+import "fmt"
+
+//
+//        CompareRequest ::= [APPLICATION 14] SEQUENCE {
+//             entry           LDAPDN,
+//             ava             AttributeValueAssertion }
+
+func (request *CompareRequest) Entry() LDAPDN {
+	return request.entry
+}
+
+func (request *CompareRequest) Ava() *AttributeValueAssertion {
+	return &request.ava
+}
+
+func readCompareRequest(bytes *Bytes) (ret CompareRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagCompareRequest, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readCompareRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (request *CompareRequest) readComponents(bytes *Bytes) (err error) {
+	request.entry, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	request.ava, err = readAttributeValueAssertion(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (request CompareRequest) write(bytes *Bytes) (size int) {
+	size += request.ava.write(bytes)
+	size += request.entry.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagCompareRequest, size)
+	return
+}
+
+func (request CompareRequest) size() (size int) {
+	size += request.entry.size()
+	size += request.ava.size()
+	size += sizeTagAndLength(TagCompareRequest, size)
+	return
+}
--- a/goldap/compare_response.go
+++ b/goldap/compare_response.go
@ -0,0 +1,29 @@
+package message
+
+import "fmt"
+
+//
+//        CompareResponse ::= [APPLICATION 15] LDAPResult
+
+func (response *CompareResponse) SetResultCode(code int) {
+	response.resultCode = ENUMERATED(code)
+}
+
+func readCompareResponse(bytes *Bytes) (ret CompareResponse, err error) {
+	var res LDAPResult
+	res, err = readTaggedLDAPResult(bytes, classApplication, TagCompareResponse)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readCompareResponse:\n%s", err.Error())}
+		return
+	}
+	ret = CompareResponse(res)
+	return
+}
+
+func (response CompareResponse) write(bytes *Bytes) int {
+	return LDAPResult(response).writeTagged(bytes, classApplication, TagCompareResponse)
+}
+
+func (response CompareResponse) size() int {
+	return LDAPResult(response).sizeTagged(TagCompareResponse)
+}
--- a/goldap/control.go
+++ b/goldap/control.go
@ -0,0 +1,94 @@
+package message
+
+import (
+	"errors"
+	"fmt"
+)
+
+//
+//        Control ::= SEQUENCE {
+//             controlType             LDAPOID,
+//             criticality             BOOLEAN DEFAULT FALSE,
+//             controlValue            OCTET STRING OPTIONAL }
+
+func (control *Control) ControlType() LDAPOID {
+	return control.controlType
+}
+
+func (control *Control) Criticality() BOOLEAN {
+	return control.criticality
+}
+
+func (control *Control) ControlValue() *OCTETSTRING {
+	return control.controlValue
+}
+
+func readControl(bytes *Bytes) (control Control, err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, control.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readControl:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (control *Control) readComponents(bytes *Bytes) (err error) {
+	control.controlType, err = readLDAPOID(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == tagBoolean {
+			control.criticality, err = readBOOLEAN(bytes)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			if control.criticality == false {
+				err = errors.New(fmt.Sprintf("readComponents: criticality default value FALSE should not be specified"))
+				return
+			}
+		}
+	}
+	if bytes.HasMoreData() {
+		var octetstring OCTETSTRING
+		octetstring, err = readOCTETSTRING(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		control.controlValue = octetstring.Pointer()
+	}
+	return
+}
+
+func (control Control) write(bytes *Bytes) (size int) {
+	if control.controlValue != nil {
+		size += control.controlValue.write(bytes)
+	}
+	if control.criticality != BOOLEAN(false) {
+		size += control.criticality.write(bytes)
+	}
+	size += control.controlType.write(bytes)
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+
+func (control Control) size() (size int) {
+	if control.controlValue != nil {
+		size += control.controlValue.size()
+	}
+	if control.criticality != BOOLEAN(false) {
+		size += control.criticality.size()
+	}
+	size += control.controlType.size()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
--- a/goldap/controls.go
+++ b/goldap/controls.go
@ -0,0 +1,44 @@
+package message
+
+import "fmt"
+
+//
+//        Controls ::= SEQUENCE OF control Control
+
+func readTaggedControls(bytes *Bytes, class int, tag int) (controls Controls, err error) {
+	err = bytes.ReadSubBytes(class, tag, controls.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedControls:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (controls *Controls) readComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var control Control
+		control, err = readControl(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		*controls = append(*controls, control)
+	}
+	return
+}
+func (controls Controls) Pointer() *Controls { return &controls }
+
+func (controls Controls) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	for i := len(controls) - 1; i >= 0; i-- {
+		size += controls[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+func (controls Controls) sizeTagged(tag int) (size int) {
+	for _, control := range controls {
+		size += control.size()
+	}
+	size += sizeTagAndLength(tag, size)
+	return
+}
--- a/goldap/del_request.go
+++ b/goldap/del_request.go
@ -0,0 +1,24 @@
+package message
+
+import "fmt"
+
+//
+//        DelRequest ::= [APPLICATION 10] LDAPDN
+func readDelRequest(bytes *Bytes) (ret DelRequest, err error) {
+	var res LDAPDN
+	res, err = readTaggedLDAPDN(bytes, classApplication, TagDelRequest)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readDelRequest:\n%s", err.Error())}
+		return
+	}
+	ret = DelRequest(res)
+	return
+}
+
+func (del DelRequest) write(bytes *Bytes) int {
+	return LDAPDN(del).writeTagged(bytes, classApplication, TagDelRequest)
+}
+
+func (del DelRequest) size() int {
+	return LDAPDN(del).sizeTagged(TagDelRequest)
+}
--- a/goldap/del_response.go
+++ b/goldap/del_response.go
@ -0,0 +1,29 @@
+package message
+
+import "fmt"
+
+//
+//        DelResponse ::= [APPLICATION 11] LDAPResult
+
+func (del *DelResponse) SetResultCode(code int) {
+	del.resultCode = ENUMERATED(code)
+}
+
+func readDelResponse(bytes *Bytes) (ret DelResponse, err error) {
+	var res LDAPResult
+	res, err = readTaggedLDAPResult(bytes, classApplication, TagDelResponse)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readDelResponse:\n%s", err.Error())}
+		return
+	}
+	ret = DelResponse(res)
+	return
+}
+
+func (del DelResponse) write(bytes *Bytes) int {
+	return LDAPResult(del).writeTagged(bytes, classApplication, TagDelResponse)
+}
+
+func (del DelResponse) size() int {
+	return LDAPResult(del).sizeTagged(TagDelResponse)
+}
--- a/goldap/dn.go
+++ b/goldap/dn.go
@ -0,0 +1,60 @@
+package message
+
+import "fmt"
+
+//
+//        LDAPDN ::= LDAPString -- Constrained to <distinguishedName>
+//                              -- [RFC4514]
+
+func readLDAPDN(bytes *Bytes) (ret LDAPDN, err error) {
+	var str LDAPString
+	str, err = readLDAPString(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readLDAPDN:\n%s", err.Error())}
+		return
+	}
+	ret = LDAPDN(str)
+	return
+}
+
+func readTaggedLDAPDN(bytes *Bytes, class int, tag int) (ret LDAPDN, err error) {
+	var ldapstring LDAPString
+	ldapstring, err = readTaggedLDAPString(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedLDAPDN:\n%s", err.Error())}
+		return
+	}
+	// @TODO: check RFC4514
+	ret = LDAPDN(ldapstring)
+	return
+}
+
+func (l LDAPDN) Pointer() *LDAPDN { return &l }
+
+func readRelativeLDAPDN(bytes *Bytes) (ret RelativeLDAPDN, err error) {
+	var ldapstring LDAPString
+	ldapstring, err = readLDAPString(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readRelativeLDAPDN:\n%s", err.Error())}
+		return
+	}
+	// @TODO: check RFC4514
+	ret = RelativeLDAPDN(ldapstring)
+	return
+}
+
+func (l LDAPDN) write(bytes *Bytes) int {
+	return LDAPString(l).write(bytes)
+}
+
+func (l LDAPDN) writeTagged(bytes *Bytes, class int, tag int) int {
+	return LDAPString(l).writeTagged(bytes, class, tag)
+}
+
+func (l LDAPDN) size() int {
+	return LDAPString(l).size()
+}
+
+func (l LDAPDN) sizeTagged(tag int) int {
+	return LDAPString(l).sizeTagged(tag)
+}
--- a/goldap/enumerated.go
+++ b/goldap/enumerated.go
@ -0,0 +1,34 @@
+package message
+
+import "fmt"
+
+func (enum ENUMERATED) Int() int {
+	return int(enum)
+}
+
+func readENUMERATED(bytes *Bytes, allowedValues map[ENUMERATED]string) (ret ENUMERATED, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(classUniversal, tagEnum, tagEnum)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readENUMERATED:\n%s", err.Error())}
+		return
+	}
+	ret = ENUMERATED(value.(int32))
+	if _, ok := allowedValues[ret]; !ok {
+		err = LdapError{fmt.Sprintf("readENUMERATED: Invalid ENUMERATED VALUE %d", ret)}
+		return
+	}
+	return
+}
+
+func (enum ENUMERATED) write(bytes *Bytes) int {
+	return bytes.WritePrimitiveSubBytes(classUniversal, tagEnum, enum)
+}
+
+func (enum ENUMERATED) writeTagged(bytes *Bytes, class int, tag int) int {
+	return bytes.WritePrimitiveSubBytes(class, tag, enum)
+}
+
+func (enum ENUMERATED) size() int {
+	return SizePrimitiveSubBytes(tagEnum, enum)
+}
--- a/goldap/error.go
+++ b/goldap/error.go
@ -0,0 +1,9 @@
+package message
+
+type LdapError struct {
+	Msg string
+}
+
+func (err LdapError) Error() string {
+	return err.Msg
+}
--- a/goldap/extended_request.go
+++ b/goldap/extended_request.go
@ -0,0 +1,69 @@
+package message
+
+import "fmt"
+
+//
+//        ExtendedRequest ::= [APPLICATION 23] SEQUENCE {
+//             requestName      [0] LDAPOID,
+//             requestValue     [1] OCTET STRING OPTIONAL }
+
+func (extended *ExtendedRequest) RequestName() LDAPOID {
+	return extended.requestName
+}
+
+func (extended *ExtendedRequest) RequestValue() *OCTETSTRING {
+	return extended.requestValue
+}
+
+func readExtendedRequest(bytes *Bytes) (ret ExtendedRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagExtendedRequest, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readExtendedRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (extended *ExtendedRequest) readComponents(bytes *Bytes) (err error) {
+	extended.requestName, err = readTaggedLDAPOID(bytes, classContextSpecific, TagExtendedRequestName)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagExtendedRequestValue {
+			var requestValue OCTETSTRING
+			requestValue, err = readTaggedOCTETSTRING(bytes, classContextSpecific, TagExtendedRequestValue)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			extended.requestValue = requestValue.Pointer()
+		}
+	}
+	return
+}
+
+func (extended ExtendedRequest) write(bytes *Bytes) (size int) {
+	if extended.requestValue != nil {
+		size += extended.requestValue.writeTagged(bytes, classContextSpecific, TagExtendedRequestValue)
+	}
+	size += extended.requestName.writeTagged(bytes, classContextSpecific, TagExtendedRequestName)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagExtendedRequest, size)
+	return
+}
+
+func (extended ExtendedRequest) size() (size int) {
+	size += extended.requestName.sizeTagged(TagExtendedRequestName)
+	if extended.requestValue != nil {
+		size += extended.requestValue.sizeTagged(TagExtendedRequestValue)
+	}
+	size += sizeTagAndLength(TagExtendedRequest, size)
+	return
+}
--- a/goldap/extended_response.go
+++ b/goldap/extended_response.go
@ -0,0 +1,85 @@
+package message
+
+import "fmt"
+
+//
+//        ExtendedResponse ::= [APPLICATION 24] SEQUENCE {
+//             COMPONENTS OF LDAPResult,
+//             responseName     [10] LDAPOID OPTIONAL,
+//             responseValue    [11] OCTET STRING OPTIONAL }
+
+func (extended *ExtendedResponse) SetResponseName(name LDAPOID) {
+	extended.responseName = &name
+}
+
+func readExtendedResponse(bytes *Bytes) (ret ExtendedResponse, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagExtendedResponse, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readExtendedResponse:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+func (extended *ExtendedResponse) readComponents(bytes *Bytes) (err error) {
+	extended.LDAPResult.readComponents(bytes)
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagExtendedResponseName {
+			var oid LDAPOID
+			oid, err = readTaggedLDAPOID(bytes, classContextSpecific, TagExtendedResponseName)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			extended.responseName = oid.Pointer()
+		}
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagExtendedResponseValue {
+			var responseValue OCTETSTRING
+			responseValue, err = readTaggedOCTETSTRING(bytes, classContextSpecific, TagExtendedResponseValue)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			extended.responseValue = responseValue.Pointer()
+		}
+	}
+	return
+}
+
+func (extended ExtendedResponse) write(bytes *Bytes) (size int) {
+	if extended.responseValue != nil {
+		size += extended.responseValue.writeTagged(bytes, classContextSpecific, TagExtendedResponseValue)
+	}
+	if extended.responseName != nil {
+		size += extended.responseName.writeTagged(bytes, classContextSpecific, TagExtendedResponseName)
+	}
+	size += extended.LDAPResult.writeComponents(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagExtendedResponse, size)
+	return
+}
+
+func (extended ExtendedResponse) size() (size int) {
+	size += extended.LDAPResult.sizeComponents()
+	if extended.responseName != nil {
+		size += extended.responseName.sizeTagged(TagExtendedResponseName)
+	}
+	if extended.responseValue != nil {
+		size += extended.responseValue.sizeTagged(TagExtendedResponseValue)
+	}
+	size += sizeTagAndLength(TagExtendedResponse, size)
+	return
+}
--- a/goldap/filter.go
+++ b/goldap/filter.go
@ -0,0 +1,70 @@
+package message
+
+import "fmt"
+
+//
+//        Filter ::= CHOICE {
+//             and             [0] SET SIZE (1..MAX) OF filter Filter,
+//             or              [1] SET SIZE (1..MAX) OF filter Filter,
+//             not             [2] Filter,
+//             equalityMatch   [3] AttributeValueAssertion,
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 57]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//             substrings      [4] SubstringFilter,
+//             greaterOrEqual  [5] AttributeValueAssertion,
+//             lessOrEqual     [6] AttributeValueAssertion,
+//             present         [7] AttributeDescription,
+//             approxMatch     [8] AttributeValueAssertion,
+//             extensibleMatch [9] MatchingRuleAssertion,
+//             ...  }
+
+func readFilter(bytes *Bytes) (filter Filter, err error) {
+	var tagAndLength TagAndLength
+	tagAndLength, err = bytes.PreviewTagAndLength()
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilter:\n%s", err.Error())}
+		return
+	}
+	err = tagAndLength.ExpectClass(classContextSpecific)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilter:\n%s", err.Error())}
+		return
+	}
+	switch tagAndLength.Tag {
+	case TagFilterAnd:
+		filter, err = readFilterAnd(bytes)
+	case TagFilterOr:
+		filter, err = readFilterOr(bytes)
+	case TagFilterNot:
+		filter, err = readFilterNot(bytes)
+	case TagFilterEqualityMatch:
+		filter, err = readFilterEqualityMatch(bytes)
+	case TagFilterSubstrings:
+		filter, err = readFilterSubstrings(bytes)
+	case TagFilterGreaterOrEqual:
+		filter, err = readFilterGreaterOrEqual(bytes)
+	case TagFilterLessOrEqual:
+		filter, err = readFilterLessOrEqual(bytes)
+	case TagFilterPresent:
+		filter, err = readFilterPresent(bytes)
+	case TagFilterApproxMatch:
+		filter, err = readFilterApproxMatch(bytes)
+	case TagFilterExtensibleMatch:
+		filter, err = readFilterExtensibleMatch(bytes)
+	default:
+		err = LdapError{fmt.Sprintf("readFilter: invalid tag value %d for filter", tagAndLength.Tag)}
+		return
+	}
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilter:\n%s", err.Error())}
+		return
+	}
+	return
+}
--- a/goldap/filter_and.go
+++ b/goldap/filter_and.go
@ -0,0 +1,54 @@
+package message
+
+import "fmt"
+
+//             and             [0] SET SIZE (1..MAX) OF filter Filter,
+
+func (filterAnd FilterAnd) getFilterTag() int {
+	return TagFilterAnd
+}
+
+func (filterAnd FilterAnd) size() (size int) {
+	for _, filter := range filterAnd {
+		size += filter.size()
+	}
+	size += sizeTagAndLength(TagFilterAnd, size)
+	return
+}
+
+func (filterAnd *FilterAnd) readComponents(bytes *Bytes) (err error) {
+	count := 0
+	for bytes.HasMoreData() {
+		count++
+		var filter Filter
+		filter, err = readFilter(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents (filter %d):\n%s", count, err.Error())}
+			return
+		}
+		*filterAnd = append(*filterAnd, filter)
+	}
+	if len(*filterAnd) == 0 {
+		err = LdapError{"readComponents: expecting at least one Filter"}
+		return
+	}
+	return
+}
+
+func (filterAnd FilterAnd) write(bytes *Bytes) (size int) {
+
+	for i := len(filterAnd) - 1; i >= 0; i-- {
+		size += filterAnd[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classContextSpecific, isCompound, TagFilterAnd, size)
+	return
+}
+
+func readFilterAnd(bytes *Bytes) (filterand FilterAnd, err error) {
+	err = bytes.ReadSubBytes(classContextSpecific, TagFilterAnd, filterand.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterAnd:\n%s", err.Error())}
+		return
+	}
+	return
+}
--- a/goldap/filter_approx_match.go
+++ b/goldap/filter_approx_match.go
@ -0,0 +1,34 @@
+package message
+
+import "fmt"
+
+//             approxMatch     [8] AttributeValueAssertion,
+func readFilterApproxMatch(bytes *Bytes) (ret FilterApproxMatch, err error) {
+	var attributevalueassertion AttributeValueAssertion
+	attributevalueassertion, err = readTaggedAttributeValueAssertion(bytes, classContextSpecific, TagFilterApproxMatch)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterApproxMatch:\n%s", err.Error())}
+		return
+	}
+	ret = FilterApproxMatch(attributevalueassertion)
+	return
+}
+
+//             approxMatch     [8] AttributeValueAssertion,
+func (f FilterApproxMatch) write(bytes *Bytes) int {
+	return AttributeValueAssertion(f).writeTagged(bytes, classContextSpecific, TagFilterApproxMatch)
+}
+func (filterAnd FilterApproxMatch) getFilterTag() int {
+	return TagFilterApproxMatch
+}
+
+//             approxMatch     [8] AttributeValueAssertion,
+func (f FilterApproxMatch) size() int {
+	return AttributeValueAssertion(f).sizeTagged(TagFilterApproxMatch)
+}
+func (a *FilterApproxMatch) AttributeDesc() AttributeDescription {
+	return a.attributeDesc
+}
+func (a *FilterApproxMatch) AssertionValue() AssertionValue {
+	return a.assertionValue
+}
--- a/goldap/filter_equality_match.go
+++ b/goldap/filter_equality_match.go
@ -0,0 +1,34 @@
+package message
+
+import "fmt"
+
+//             equalityMatch   [3] AttributeValueAssertion,
+func readFilterEqualityMatch(bytes *Bytes) (ret FilterEqualityMatch, err error) {
+	var attributevalueassertion AttributeValueAssertion
+	attributevalueassertion, err = readTaggedAttributeValueAssertion(bytes, classContextSpecific, TagFilterEqualityMatch)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterEqualityMatch:\n%s", err.Error())}
+		return
+	}
+	ret = FilterEqualityMatch(attributevalueassertion)
+	return
+}
+
+//             equalityMatch   [3] AttributeValueAssertion,
+func (f FilterEqualityMatch) write(bytes *Bytes) int {
+	return AttributeValueAssertion(f).writeTagged(bytes, classContextSpecific, TagFilterEqualityMatch)
+}
+func (filter FilterEqualityMatch) getFilterTag() int {
+	return TagFilterEqualityMatch
+}
+
+//             equalityMatch   [3] AttributeValueAssertion,
+func (f FilterEqualityMatch) size() int {
+	return AttributeValueAssertion(f).sizeTagged(TagFilterEqualityMatch)
+}
+func (a *FilterEqualityMatch) AttributeDesc() AttributeDescription {
+	return a.attributeDesc
+}
+func (a *FilterEqualityMatch) AssertionValue() AssertionValue {
+	return a.assertionValue
+}
--- a/goldap/filter_extensible_match.go
+++ b/goldap/filter_extensible_match.go
@ -0,0 +1,28 @@
+package message
+
+import "fmt"
+
+//             extensibleMatch [9] MatchingRuleAssertion,
+func readFilterExtensibleMatch(bytes *Bytes) (filterextensiblematch FilterExtensibleMatch, err error) {
+	var matchingruleassertion MatchingRuleAssertion
+	matchingruleassertion, err = readTaggedMatchingRuleAssertion(bytes, classContextSpecific, TagFilterExtensibleMatch)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterExtensibleMatch:\n%s", err.Error())}
+		return
+	}
+	filterextensiblematch = FilterExtensibleMatch(matchingruleassertion)
+	return
+}
+
+//             extensibleMatch [9] MatchingRuleAssertion,
+func (f FilterExtensibleMatch) write(bytes *Bytes) int {
+	return MatchingRuleAssertion(f).writeTagged(bytes, classContextSpecific, TagFilterExtensibleMatch)
+}
+func (filterAnd FilterExtensibleMatch) getFilterTag() int {
+	return TagFilterExtensibleMatch
+}
+
+//             extensibleMatch [9] MatchingRuleAssertion,
+func (f FilterExtensibleMatch) size() int {
+	return MatchingRuleAssertion(f).sizeTagged(TagFilterExtensibleMatch)
+}
--- a/goldap/filter_greater_or_equal.go
+++ b/goldap/filter_greater_or_equal.go
@ -0,0 +1,34 @@
+package message
+
+import "fmt"
+
+//             greaterOrEqual  [5] AttributeValueAssertion,
+func readFilterGreaterOrEqual(bytes *Bytes) (ret FilterGreaterOrEqual, err error) {
+	var attributevalueassertion AttributeValueAssertion
+	attributevalueassertion, err = readTaggedAttributeValueAssertion(bytes, classContextSpecific, TagFilterGreaterOrEqual)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterGreaterOrEqual:\n%s", err.Error())}
+		return
+	}
+	ret = FilterGreaterOrEqual(attributevalueassertion)
+	return
+}
+
+//             greaterOrEqual  [5] AttributeValueAssertion,
+func (filter FilterGreaterOrEqual) write(bytes *Bytes) int {
+	return AttributeValueAssertion(filter).writeTagged(bytes, classContextSpecific, TagFilterGreaterOrEqual)
+}
+func (filter FilterGreaterOrEqual) getFilterTag() int {
+	return TagFilterGreaterOrEqual
+}
+
+//             greaterOrEqual  [5] AttributeValueAssertion,
+func (filter FilterGreaterOrEqual) size() int {
+	return AttributeValueAssertion(filter).sizeTagged(TagFilterGreaterOrEqual)
+}
+func (filter *FilterGreaterOrEqual) AttributeDesc() AttributeDescription {
+	return filter.attributeDesc
+}
+func (filter *FilterGreaterOrEqual) AssertionValue() AssertionValue {
+	return filter.assertionValue
+}
--- a/goldap/filter_less_or_equal.go
+++ b/goldap/filter_less_or_equal.go
@ -0,0 +1,34 @@
+package message
+
+import "fmt"
+
+//             lessOrEqual     [6] AttributeValueAssertion,
+func readFilterLessOrEqual(bytes *Bytes) (ret FilterLessOrEqual, err error) {
+	var attributevalueassertion AttributeValueAssertion
+	attributevalueassertion, err = readTaggedAttributeValueAssertion(bytes, classContextSpecific, TagFilterLessOrEqual)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterLessOrEqual:\n%s", err.Error())}
+		return
+	}
+	ret = FilterLessOrEqual(attributevalueassertion)
+	return
+}
+
+//             lessOrEqual     [6] AttributeValueAssertion,
+func (f FilterLessOrEqual) write(bytes *Bytes) int {
+	return AttributeValueAssertion(f).writeTagged(bytes, classContextSpecific, TagFilterLessOrEqual)
+}
+func (filterAnd FilterLessOrEqual) getFilterTag() int {
+	return TagFilterLessOrEqual
+}
+
+//             lessOrEqual     [6] AttributeValueAssertion,
+func (f FilterLessOrEqual) size() int {
+	return AttributeValueAssertion(f).sizeTagged(TagFilterLessOrEqual)
+}
+func (a *FilterLessOrEqual) AttributeDesc() AttributeDescription {
+	return a.attributeDesc
+}
+func (a *FilterLessOrEqual) AssertionValue() AssertionValue {
+	return a.assertionValue
+}
--- a/goldap/filter_not.go
+++ b/goldap/filter_not.go
@ -0,0 +1,40 @@
+package message
+
+import "fmt"
+
+func (filterNot FilterNot) getFilterTag() int {
+	return TagFilterNot
+}
+
+//             not             [2] Filter,
+func (filterNot FilterNot) size() (size int) {
+	size = filterNot.Filter.size()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+
+func (filterNot *FilterNot) readComponents(bytes *Bytes) (err error) {
+	filterNot.Filter, err = readFilter(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+//             not             [2] Filter,
+func (filterNot FilterNot) write(bytes *Bytes) (size int) {
+	size = filterNot.Filter.write(bytes)
+	size += bytes.WriteTagAndLength(classContextSpecific, isCompound, TagFilterNot, size)
+	return
+}
+
+//             not             [2] Filter,
+func readFilterNot(bytes *Bytes) (filternot FilterNot, err error) {
+	err = bytes.ReadSubBytes(classContextSpecific, TagFilterNot, filternot.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterNot:\n%s", err.Error())}
+		return
+	}
+	return
+}
--- a/goldap/filter_or.go
+++ b/goldap/filter_or.go
@ -0,0 +1,52 @@
+package message
+
+import "fmt"
+
+//             or              [1] SET SIZE (1..MAX) OF filter Filter,
+func readFilterOr(bytes *Bytes) (filteror FilterOr, err error) {
+	err = bytes.ReadSubBytes(classContextSpecific, TagFilterOr, filteror.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterOr:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (filteror *FilterOr) readComponents(bytes *Bytes) (err error) {
+	count := 0
+	for bytes.HasMoreData() {
+		count++
+		var filter Filter
+		filter, err = readFilter(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents (filter %d): %s", count, err.Error())}
+			return
+		}
+		*filteror = append(*filteror, filter)
+	}
+	if len(*filteror) == 0 {
+		err = LdapError{"readComponents: expecting at least one Filter"}
+		return
+	}
+	return
+}
+
+//             or              [1] SET SIZE (1..MAX) OF filter Filter,
+func (f FilterOr) write(bytes *Bytes) (size int) {
+	for i := len(f) - 1; i >= 0; i-- {
+		size += f[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classContextSpecific, isCompound, TagFilterOr, size)
+	return
+}
+func (filter FilterOr) getFilterTag() int {
+	return TagFilterOr
+}
+
+//             or              [1] SET SIZE (1..MAX) OF filter Filter,
+func (f FilterOr) size() (size int) {
+	for _, filter := range f {
+		size += filter.size()
+	}
+	size += sizeTagAndLength(TagFilterOr, size)
+	return
+}
--- a/goldap/filter_present.go
+++ b/goldap/filter_present.go
@ -0,0 +1,28 @@
+package message
+
+import "fmt"
+
+//             present         [7] AttributeDescription,
+func readFilterPresent(bytes *Bytes) (ret FilterPresent, err error) {
+	var attributedescription AttributeDescription
+	attributedescription, err = readTaggedAttributeDescription(bytes, classContextSpecific, TagFilterPresent)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterPresent:\n%s", err.Error())}
+		return
+	}
+	ret = FilterPresent(attributedescription)
+	return
+}
+
+//             present         [7] AttributeDescription,
+func (f FilterPresent) write(bytes *Bytes) int {
+	return AttributeDescription(f).writeTagged(bytes, classContextSpecific, TagFilterPresent)
+}
+func (filterAnd FilterPresent) getFilterTag() int {
+	return TagFilterPresent
+}
+
+//             present         [7] AttributeDescription,
+func (f FilterPresent) size() int {
+	return AttributeDescription(f).sizeTagged(TagFilterPresent)
+}
--- a/goldap/filter_substring.go
+++ b/goldap/filter_substring.go
@ -0,0 +1,187 @@
+package message
+
+import "fmt"
+
+//             substrings      [4] SubstringFilter,
+func readFilterSubstrings(bytes *Bytes) (filtersubstrings FilterSubstrings, err error) {
+	var substringfilter SubstringFilter
+	substringfilter, err = readTaggedSubstringFilter(bytes, classContextSpecific, TagFilterSubstrings)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readFilterSubstrings:\n%s", err.Error())}
+		return
+	}
+	filtersubstrings = FilterSubstrings(substringfilter)
+	return
+}
+
+//
+//        SubstringFilter ::= SEQUENCE {
+//             type           AttributeDescription,
+//             substrings     SEQUENCE SIZE (1..MAX) OF substring CHOICE {
+//                  initial [0] AssertionValue,  -- can occur at most once
+//                  any     [1] AssertionValue,
+//                  final   [2] AssertionValue } -- can occur at most once
+//             }
+func readTaggedSubstringFilter(bytes *Bytes, class int, tag int) (substringfilter SubstringFilter, err error) {
+	err = bytes.ReadSubBytes(class, tag, substringfilter.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedSubstringFilter:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (substringfilter *SubstringFilter) readComponents(bytes *Bytes) (err error) {
+	substringfilter.type_, err = readAttributeDescription(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	err = substringfilter.readSubstrings(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (substringfilter *SubstringFilter) readSubstrings(bytes *Bytes) (err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, substringfilter.readSubstringsComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readSubstrings:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (substringfilter *SubstringFilter) readSubstringsComponents(bytes *Bytes) (err error) {
+	var foundInitial = 0
+	var foundFinal = 0
+	var tagAndLength TagAndLength
+	for bytes.HasMoreData() {
+		tagAndLength, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readSubstringsComponents:\n%s", err.Error())}
+			return
+		}
+		var assertionvalue AssertionValue
+		switch tagAndLength.Tag {
+		case TagSubstringInitial:
+			foundInitial++
+			if foundInitial > 1 {
+				err = LdapError{"readSubstringsComponents: initial can occur at most once"}
+				return
+			}
+			assertionvalue, err = readTaggedAssertionValue(bytes, classContextSpecific, TagSubstringInitial)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readSubstringsComponents:\n%s", err.Error())}
+				return
+			}
+			substringfilter.substrings = append(substringfilter.substrings, SubstringInitial(assertionvalue))
+		case TagSubstringAny:
+			assertionvalue, err = readTaggedAssertionValue(bytes, classContextSpecific, TagSubstringAny)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readSubstringsComponents:\n%s", err.Error())}
+				return
+			}
+			substringfilter.substrings = append(substringfilter.substrings, SubstringAny(assertionvalue))
+		case TagSubstringFinal:
+			foundFinal++
+			if foundFinal > 1 {
+				err = LdapError{"readSubstringsComponents: final can occur at most once"}
+				return
+			}
+			assertionvalue, err = readTaggedAssertionValue(bytes, classContextSpecific, TagSubstringFinal)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readSubstringsComponents:\n%s", err.Error())}
+				return
+			}
+			substringfilter.substrings = append(substringfilter.substrings, SubstringFinal(assertionvalue))
+		default:
+			err = LdapError{fmt.Sprintf("readSubstringsComponents: invalid tag %d", tagAndLength.Tag)}
+			return
+		}
+	}
+	if len(substringfilter.substrings) == 0 {
+		err = LdapError{"readSubstringsComponents: expecting at least one substring"}
+		return
+	}
+	return
+}
+
+//             substrings      [4] SubstringFilter,
+func (f FilterSubstrings) write(bytes *Bytes) int {
+	return SubstringFilter(f).writeTagged(bytes, classContextSpecific, TagFilterSubstrings)
+}
+func (s SubstringFilter) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	for i := len(s.substrings) - 1; i >= 0; i-- {
+		substring := s.substrings[i]
+		switch substring.(type) {
+		case SubstringInitial:
+			size += AssertionValue(substring.(SubstringInitial)).writeTagged(bytes, classContextSpecific, TagSubstringInitial)
+		case SubstringAny:
+			size += AssertionValue(substring.(SubstringAny)).writeTagged(bytes, classContextSpecific, TagSubstringAny)
+		case SubstringFinal:
+			size += AssertionValue(substring.(SubstringFinal)).writeTagged(bytes, classContextSpecific, TagSubstringFinal)
+		default:
+			panic("Unknown type for SubstringFilter substring")
+		}
+	}
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	size += s.type_.write(bytes)
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+//
+//        SubstringFilter ::= SEQUENCE {
+//             type           AttributeDescription,
+//             substrings     SEQUENCE SIZE (1..MAX) OF substring CHOICE {
+//                  initial [0] AssertionValue,  -- can occur at most once
+//                  any     [1] AssertionValue,
+//                  final   [2] AssertionValue } -- can occur at most once
+//             }
+func (s SubstringFilter) write(bytes *Bytes) (size int) {
+	return s.writeTagged(bytes, classUniversal, tagSequence)
+}
+func (filter FilterSubstrings) getFilterTag() int {
+	return TagFilterSubstrings
+}
+
+//             substrings      [4] SubstringFilter,
+func (f FilterSubstrings) size() int {
+	return SubstringFilter(f).sizeTagged(TagFilterSubstrings)
+}
+
+//
+//        SubstringFilter ::= SEQUENCE {
+//             type           AttributeDescription,
+//             substrings     SEQUENCE SIZE (1..MAX) OF substring CHOICE {
+//                  initial [0] AssertionValue,  -- can occur at most once
+//                  any     [1] AssertionValue,
+//                  final   [2] AssertionValue } -- can occur at most once
+//             }
+func (s SubstringFilter) size() (size int) {
+	return s.sizeTagged(tagSequence)
+}
+func (s SubstringFilter) sizeTagged(tag int) (size int) {
+	for _, substring := range s.substrings {
+		switch substring.(type) {
+		case SubstringInitial:
+			size += AssertionValue(substring.(SubstringInitial)).sizeTagged(TagSubstringInitial)
+		case SubstringAny:
+			size += AssertionValue(substring.(SubstringAny)).sizeTagged(TagSubstringAny)
+		case SubstringFinal:
+			size += AssertionValue(substring.(SubstringFinal)).sizeTagged(TagSubstringFinal)
+		default:
+			panic("Unknown type for SubstringFilter substring")
+		}
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	size += s.type_.size()
+	size += sizeTagAndLength(tag, size)
+	return
+}
+func (s *FilterSubstrings) Type_() AttributeDescription {
+	return s.type_
+}
+func (s *FilterSubstrings) Substrings() []Substring {
+	return s.substrings
+}
--- a/goldap/integer.go
+++ b/goldap/integer.go
@ -0,0 +1,53 @@
+package message
+
+import "fmt"
+
+func readINTEGER(bytes *Bytes) (ret INTEGER, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(classUniversal, tagInteger, tagInteger)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readINTEGER:\n%s", err.Error())}
+		return
+	}
+	ret = INTEGER(value.(int32))
+	return
+}
+func readTaggedINTEGER(bytes *Bytes, class int, tag int) (ret INTEGER, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(class, tag, tagInteger)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedINTEGER:\n%s", err.Error())}
+		return
+	}
+	ret = INTEGER(value.(int32))
+	return
+}
+func readTaggedPositiveINTEGER(bytes *Bytes, class int, tag int) (ret INTEGER, err error) {
+	ret, err = readTaggedINTEGER(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedPositiveINTEGER:\n%s", err.Error())}
+		return
+	}
+	if !(ret >= 0 && ret <= maxInt) {
+		err = LdapError{fmt.Sprintf("readTaggedPositiveINTEGER: Invalid INTEGER value %d ! Expected value between 0 and %d", ret, maxInt)}
+	}
+	return
+}
+func readPositiveINTEGER(bytes *Bytes) (ret INTEGER, err error) {
+	return readTaggedPositiveINTEGER(bytes, classUniversal, tagInteger)
+}
+func (i INTEGER) write(bytes *Bytes) int {
+	return bytes.WritePrimitiveSubBytes(classUniversal, tagInteger, i)
+}
+func (i INTEGER) writeTagged(bytes *Bytes, class int, tag int) int {
+	return bytes.WritePrimitiveSubBytes(class, tag, i)
+}
+func (i INTEGER) size() int {
+	return SizePrimitiveSubBytes(tagInteger, i)
+}
+func (i INTEGER) sizeTagged(tag int) int {
+	return SizePrimitiveSubBytes(tag, i)
+}
+func (l INTEGER) Int() int {
+	return int(l)
+}
--- a/goldap/intermediate_response.go
+++ b/goldap/intermediate_response.go
@ -0,0 +1,89 @@
+package message
+
+import "fmt"
+
+//
+//        IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
+//             responseName     [0] LDAPOID OPTIONAL,
+//             responseValue    [1] OCTET STRING OPTIONAL }
+func readIntermediateResponse(bytes *Bytes) (ret IntermediateResponse, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagIntermediateResponse, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readIntermediateResponse:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (bytes *Bytes) PreviewTagAndLength() (tagAndLength TagAndLength, err error) {
+	previousOffset := bytes.offset // Save offset
+	tagAndLength, err = bytes.ParseTagAndLength()
+	bytes.offset = previousOffset // Restore offset
+	return
+}
+func (res *IntermediateResponse) readComponents(bytes *Bytes) (err error) {
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagIntermediateResponseName {
+			var oid LDAPOID
+			oid, err = readTaggedLDAPOID(bytes, classContextSpecific, TagIntermediateResponseName)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			res.responseName = oid.Pointer()
+		}
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagIntermediateResponseValue {
+			var str OCTETSTRING
+			str, err = readTaggedOCTETSTRING(bytes, classContextSpecific, TagIntermediateResponseValue)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			res.responseValue = str.Pointer()
+		}
+	}
+	return
+}
+
+//
+//        IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
+//             responseName     [0] LDAPOID OPTIONAL,
+//             responseValue    [1] OCTET STRING OPTIONAL }
+func (i IntermediateResponse) write(bytes *Bytes) (size int) {
+	if i.responseValue != nil {
+		size += i.responseValue.writeTagged(bytes, classContextSpecific, TagIntermediateResponseValue)
+	}
+	if i.responseName != nil {
+		size += i.responseName.writeTagged(bytes, classContextSpecific, TagIntermediateResponseName)
+	}
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagIntermediateResponse, size)
+	return
+}
+
+//
+//        IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
+//             responseName     [0] LDAPOID OPTIONAL,
+//             responseValue    [1] OCTET STRING OPTIONAL }
+func (i IntermediateResponse) size() (size int) {
+	if i.responseName != nil {
+		size += i.responseName.sizeTagged(TagIntermediateResponseName)
+	}
+	if i.responseValue != nil {
+		size += i.responseValue.sizeTagged(TagIntermediateResponseValue)
+	}
+	size += sizeTagAndLength(TagIntermediateResponse, size)
+	return
+}
--- a/goldap/matching_rule_assertion.go
+++ b/goldap/matching_rule_assertion.go
@ -0,0 +1,117 @@
+package message
+
+import "fmt"
+
+//
+//        MatchingRuleAssertion ::= SEQUENCE {
+//             matchingRule    [1] MatchingRuleId OPTIONAL,
+//             type            [2] AttributeDescription OPTIONAL,
+//             matchValue      [3] AssertionValue,
+//             dnAttributes    [4] BOOLEAN DEFAULT FALSE }
+func readTaggedMatchingRuleAssertion(bytes *Bytes, class int, tag int) (ret MatchingRuleAssertion, err error) {
+	err = bytes.ReadSubBytes(class, tag, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedMatchingRuleAssertion:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (matchingruleassertion *MatchingRuleAssertion) readComponents(bytes *Bytes) (err error) {
+	err = matchingruleassertion.readMatchingRule(bytes)
+	if err != nil {
+		return LdapError{fmt.Sprintf("readComponents: %s", err.Error())}
+	}
+	err = matchingruleassertion.readType(bytes)
+	if err != nil {
+		return LdapError{fmt.Sprintf("readComponents: %s", err.Error())}
+	}
+	matchingruleassertion.matchValue, err = readTaggedAssertionValue(bytes, classContextSpecific, TagMatchingRuleAssertionMatchValue)
+	if err != nil {
+		return LdapError{fmt.Sprintf("readComponents: %s", err.Error())}
+	}
+	matchingruleassertion.dnAttributes, err = readTaggedBOOLEAN(bytes, classContextSpecific, TagMatchingRuleAssertionDnAttributes)
+	if err != nil {
+		return LdapError{fmt.Sprintf("readComponents: %s", err.Error())}
+	}
+	return
+}
+func (matchingruleassertion *MatchingRuleAssertion) readMatchingRule(bytes *Bytes) (err error) {
+	var tagAndLength TagAndLength
+	tagAndLength, err = bytes.PreviewTagAndLength()
+	if err != nil {
+		return LdapError{fmt.Sprintf("readMatchingRule: %s", err.Error())}
+	}
+	if tagAndLength.Tag == TagMatchingRuleAssertionMatchingRule {
+		var matchingRule MatchingRuleId
+		matchingRule, err = readTaggedMatchingRuleId(bytes, classContextSpecific, TagMatchingRuleAssertionMatchingRule)
+		if err != nil {
+			return LdapError{fmt.Sprintf("readMatchingRule: %s", err.Error())}
+		}
+		matchingruleassertion.matchingRule = matchingRule.Pointer()
+	}
+	return
+}
+func (matchingruleassertion *MatchingRuleAssertion) readType(bytes *Bytes) (err error) {
+	var tagAndLength TagAndLength
+	tagAndLength, err = bytes.PreviewTagAndLength()
+	if err != nil {
+		return LdapError{fmt.Sprintf("readType: %s", err.Error())}
+	}
+	if tagAndLength.Tag == TagMatchingRuleAssertionType {
+		var attributedescription AttributeDescription
+		attributedescription, err = readTaggedAttributeDescription(bytes, classContextSpecific, TagMatchingRuleAssertionType)
+		if err != nil {
+			return LdapError{fmt.Sprintf("readType: %s", err.Error())}
+		}
+		matchingruleassertion.type_ = &attributedescription
+	}
+	return
+}
+func (m MatchingRuleAssertion) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	if m.dnAttributes != BOOLEAN(false) {
+		size += m.dnAttributes.writeTagged(bytes, classContextSpecific, TagMatchingRuleAssertionDnAttributes)
+	}
+	size += m.matchValue.writeTagged(bytes, classContextSpecific, TagMatchingRuleAssertionMatchValue)
+	if m.type_ != nil {
+		size += m.type_.writeTagged(bytes, classContextSpecific, TagMatchingRuleAssertionType)
+	}
+	if m.matchingRule != nil {
+		size += m.matchingRule.writeTagged(bytes, classContextSpecific, TagMatchingRuleAssertionMatchingRule)
+	}
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+//
+//        MatchingRuleAssertion ::= SEQUENCE {
+//             matchingRule    [1] MatchingRuleId OPTIONAL,
+//             type            [2] AttributeDescription OPTIONAL,
+//             matchValue      [3] AssertionValue,
+//             dnAttributes    [4] BOOLEAN DEFAULT FALSE }
+func (m MatchingRuleAssertion) write(bytes *Bytes) (size int) {
+	return m.writeTagged(bytes, classUniversal, tagSequence)
+}
+
+//
+//        MatchingRuleAssertion ::= SEQUENCE {
+//             matchingRule    [1] MatchingRuleId OPTIONAL,
+//             type            [2] AttributeDescription OPTIONAL,
+//             matchValue      [3] AssertionValue,
+//             dnAttributes    [4] BOOLEAN DEFAULT FALSE }
+func (m MatchingRuleAssertion) size() (size int) {
+	return m.sizeTagged(tagSequence)
+}
+func (m MatchingRuleAssertion) sizeTagged(tag int) (size int) {
+	if m.matchingRule != nil {
+		size += m.matchingRule.sizeTagged(TagMatchingRuleAssertionMatchingRule)
+	}
+	if m.type_ != nil {
+		size += m.type_.sizeTagged(TagMatchingRuleAssertionType)
+	}
+	size += m.matchValue.sizeTagged(TagMatchingRuleAssertionMatchValue)
+	if m.dnAttributes != BOOLEAN(false) {
+		size += m.dnAttributes.sizeTagged(TagMatchingRuleAssertionDnAttributes)
+	}
+	size += sizeTagAndLength(tag, size)
+	return
+}
--- a/goldap/matching_rule_id.go
+++ b/goldap/matching_rule_id.go
@ -0,0 +1,29 @@
+package message
+
+import "fmt"
+
+//
+//        MatchingRuleId ::= LDAPString
+func readTaggedMatchingRuleId(bytes *Bytes, class int, tag int) (matchingruleid MatchingRuleId, err error) {
+	var ldapstring LDAPString
+	ldapstring, err = readTaggedLDAPString(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedMatchingRuleId:\n%s", err.Error())}
+		return
+	}
+	matchingruleid = MatchingRuleId(ldapstring)
+	return
+}
+func (m MatchingRuleId) Pointer() *MatchingRuleId { return &m }
+
+//
+//        MatchingRuleId ::= LDAPString
+func (m MatchingRuleId) writeTagged(bytes *Bytes, class int, tag int) int {
+	return LDAPString(m).writeTagged(bytes, class, tag)
+}
+
+//
+//        MatchingRuleId ::= LDAPString
+func (m MatchingRuleId) sizeTagged(tag int) int {
+	return LDAPString(m).sizeTagged(tag)
+}
--- a/goldap/message.go
+++ b/goldap/message.go
@ -0,0 +1,139 @@
+package message
+
+import (
+	"fmt"
+	"reflect"
+)
+
+//   This appendix is normative.
+//
+//        Lightweight-Directory-Access-Protocol-V3 {1 3 6 1 1 18}
+//        -- Copyright (C) The Internet Society (2006).  This version of
+//        -- this ASN.1 module is part of RFC 4511; see the RFC itself
+//        -- for full legal notices.
+//        DEFINITIONS
+//        IMPLICIT TAGS
+//        EXTENSIBILITY IMPLIED ::=
+//
+//        BEGIN
+//
+//        LDAPMessage ::= SEQUENCE {
+//             messageID       MessageID,
+//             protocolOp      CHOICE {
+//                  bindRequest           BindRequest,
+//                  bindResponse          BindResponse,
+//                  unbindRequest         UnbindRequest,
+//                  searchRequest         SearchRequest,
+//                  searchResEntry        SearchResultEntry,
+//                  searchResDone         SearchResultDone,
+//                  searchResRef          SearchResultReference,
+//                  modifyRequest         ModifyRequest,
+//                  modifyResponse        ModifyResponse,
+//                  addRequest            AddRequest,
+//                  addResponse           AddResponse,
+//                  delRequest            DelRequest,
+//                  delResponse           DelResponse,
+//                  modDNRequest          ModifyDNRequest,
+//                  modDNResponse         ModifyDNResponse,
+//                  compareRequest        CompareRequest,
+//                  compareResponse       CompareResponse,
+//                  abandonRequest        AbandonRequest,
+//                  extendedReq           ExtendedRequest,
+//                  extendedResp          ExtendedResponse,
+//                  ...,
+//                  intermediateResponse  IntermediateResponse },
+//             controls       [0] Controls OPTIONAL }
+//
+
+func NewLDAPMessage() *LDAPMessage { return &LDAPMessage{} }
+
+func (message *LDAPMessage) readComponents(bytes *Bytes) (err error) {
+	message.messageID, err = readMessageID(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	message.protocolOp, err = readProtocolOp(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagLDAPMessageControls {
+			var controls Controls
+			controls, err = readTaggedControls(bytes, classContextSpecific, TagLDAPMessageControls)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			message.controls = controls.Pointer()
+		}
+	}
+	return
+}
+
+func (m *LDAPMessage) Write() (bytes *Bytes, err error) {
+	defer func() {
+		if e := recover(); e != nil {
+			err = LdapError{fmt.Sprintf("Error in LDAPMessage.Write: %s", e)}
+		}
+	}()
+	// Compute the needed size
+	totalSize := m.size()
+	// Initialize the structure
+	bytes = &Bytes{
+		bytes:  make([]byte, totalSize),
+		offset: totalSize,
+	}
+
+	// Go !
+	size := 0
+	if m.controls != nil {
+		size += m.controls.writeTagged(bytes, classContextSpecific, TagLDAPMessageControls)
+	}
+	size += m.protocolOp.write(bytes)
+	size += m.messageID.write(bytes)
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	// Check
+	if size != totalSize || bytes.offset != 0 {
+		err = LdapError{fmt.Sprintf("Something went wrong while writing the message ! Size is %d instead of %d, final offset is %d instead of 0", size, totalSize, bytes.offset)}
+	}
+	return
+}
+func (m *LDAPMessage) size() (size int) {
+	size += m.messageID.size()
+	size += m.protocolOp.size()
+	if m.controls != nil {
+		size += m.controls.sizeTagged(TagLDAPMessageControls)
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+func (l *LDAPMessage) MessageID() MessageID {
+	return l.messageID
+}
+func (l *LDAPMessage) SetMessageID(ID int) {
+	l.messageID = MessageID(ID)
+}
+func (l *LDAPMessage) Controls() *Controls {
+	return l.controls
+}
+func (l *LDAPMessage) ProtocolOp() ProtocolOp {
+	return l.protocolOp
+}
+func (l *LDAPMessage) ProtocolOpName() string {
+	return reflect.TypeOf(l.ProtocolOp()).Name()
+}
+func (l *LDAPMessage) ProtocolOpType() int {
+	switch l.protocolOp.(type) {
+	case BindRequest:
+		return TagBindRequest
+	}
+	return 0
+}
--- a/goldap/message_id.go
+++ b/goldap/message_id.go
@ -0,0 +1,46 @@
+package message
+
+import "fmt"
+
+func readTaggedMessageID(bytes *Bytes, class int, tag int) (ret MessageID, err error) {
+	var integer INTEGER
+	integer, err = readTaggedPositiveINTEGER(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedMessageID:\n%s", err.Error())}
+		return
+	}
+	return MessageID(integer), err
+}
+
+//        MessageID ::= INTEGER (0 ..  maxInt)
+//
+//        maxInt INTEGER ::= 2147483647 -- (2^^31 - 1) --
+//
+func readMessageID(bytes *Bytes) (ret MessageID, err error) {
+	return readTaggedMessageID(bytes, classUniversal, tagInteger)
+}
+
+//        MessageID ::= INTEGER (0 ..  maxInt)
+//
+//        maxInt INTEGER ::= 2147483647 -- (2^^31 - 1) --
+//
+func (m MessageID) write(bytes *Bytes) int {
+	return INTEGER(m).write(bytes)
+}
+func (m MessageID) writeTagged(bytes *Bytes, class int, tag int) int {
+	return INTEGER(m).writeTagged(bytes, class, tag)
+}
+
+//        MessageID ::= INTEGER (0 ..  maxInt)
+//
+//        maxInt INTEGER ::= 2147483647 -- (2^^31 - 1) --
+//
+func (m MessageID) size() int {
+	return INTEGER(m).size()
+}
+func (m MessageID) sizeTagged(tag int) int {
+	return INTEGER(m).sizeTagged(tag)
+}
+func (l MessageID) Int() int {
+	return int(l)
+}
--- a/goldap/message_test.go
+++ b/goldap/message_test.go
@ -0,0 +1,76 @@
+package message
+
+import (
+  "testing"
+  "fmt"
+)
+
+func toHex(b []byte) (r string) {
+  r = "[ "
+  for _, e := range b {
+    r += fmt.Sprintf("0x%x ", e)
+  }
+  return r + "]"
+}
+
+func TestMessageID(t *testing.T) {
+	m := NewLDAPMessageWithProtocolOp(UnbindRequest{})
+	m.SetMessageID(128)
+	buf, err := m.Write()
+	if err != nil {
+		t.Errorf("marshalling failed with %v", err)
+	}
+	t.Logf("%v", toHex(buf.Bytes()))
+
+	ret, err := ReadLDAPMessage(NewBytes(0, buf.Bytes()))
+	if err != nil {
+		t.Errorf("unmarshalling failed with %v", err)
+	}
+	if _, ok := ret.ProtocolOp().(UnbindRequest); !ok {
+		t.Errorf("should be an unbind request")
+	}
+	if ret.MessageID() != 128 {
+		t.Errorf("Expect message id 128, got %d", ret.MessageID())
+	}
+	t.Log("Done, marshal/unmarshall worked")
+}
+
+func TestSearchEntry(t *testing.T) {
+	m := NewLDAPMessageWithProtocolOp(SearchResultEntry{
+		objectName:"cn=êige€nbgtz,ou=users,dc=deuxfleurs,dc=fr", 
+		attributes: PartialAttributeList{
+			PartialAttribute{
+				type_:"displayname",
+				vals:[]AttributeValue{"êiGe€NBgTZ"},
+			},
+			PartialAttribute{
+				type_:"objectclass",
+				vals:[]AttributeValue{"inetOrgPerson"},
+			},
+			PartialAttribute{
+				type_:"objectclass", 
+				vals:[]AttributeValue{"organizationalPerson"},
+			},
+			PartialAttribute{
+				type_:"objectclass", 
+				vals:[]AttributeValue{"person"},
+			},
+			PartialAttribute{
+				type_:"objectclass",
+				vals:[]AttributeValue{"top"},
+			},
+			PartialAttribute{
+				type_:"structuralobjectclass",
+				vals:[]AttributeValue{"inetOrgPerson"},
+			},
+		},
+	})
+	m.SetMessageID(24)
+	buf, err := m.Write()
+	if err != nil {
+		t.Errorf("marshalling failed with %v", err)
+	}
+	if buf.Bytes()[0] != 0x30 {
+		t.Logf("Malformed message: %v", toHex(buf.Bytes()))
+	}
+}
--- a/goldap/modify_dn_request.go
+++ b/goldap/modify_dn_request.go
@ -0,0 +1,87 @@
+package message
+
+import "fmt"
+
+//
+//        ModifyDNRequest ::= [APPLICATION 12] SEQUENCE {
+//             entry           LDAPDN,
+//             newrdn          RelativeLDAPDN,
+//             deleteoldrdn    BOOLEAN,
+//             newSuperior     [0] LDAPDN OPTIONAL }
+func readModifyDNRequest(bytes *Bytes) (ret ModifyDNRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagModifyDNRequest, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readModifyDNRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (req *ModifyDNRequest) readComponents(bytes *Bytes) (err error) {
+	req.entry, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	req.newrdn, err = readRelativeLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	req.deleteoldrdn, err = readBOOLEAN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagModifyDNRequestNewSuperior {
+			var ldapdn LDAPDN
+			ldapdn, err = readTaggedLDAPDN(bytes, classContextSpecific, TagModifyDNRequestNewSuperior)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			req.newSuperior = ldapdn.Pointer()
+		}
+	}
+	return
+}
+
+//
+//        ModifyDNRequest ::= [APPLICATION 12] SEQUENCE {
+//             entry           LDAPDN,
+//             newrdn          RelativeLDAPDN,
+//             deleteoldrdn    BOOLEAN,
+//             newSuperior     [0] LDAPDN OPTIONAL }
+func (m ModifyDNRequest) write(bytes *Bytes) (size int) {
+	if m.newSuperior != nil {
+		size += m.newSuperior.writeTagged(bytes, classContextSpecific, TagModifyDNRequestNewSuperior)
+	}
+	size += m.deleteoldrdn.write(bytes)
+	size += m.newrdn.write(bytes)
+	size += m.entry.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagModifyDNRequest, size)
+	return
+}
+
+//
+//        ModifyDNRequest ::= [APPLICATION 12] SEQUENCE {
+//             entry           LDAPDN,
+//             newrdn          RelativeLDAPDN,
+//             deleteoldrdn    BOOLEAN,
+//             newSuperior     [0] LDAPDN OPTIONAL }
+func (m ModifyDNRequest) size() (size int) {
+	size += m.entry.size()
+	size += m.newrdn.size()
+	size += m.deleteoldrdn.size()
+	if m.newSuperior != nil {
+		size += m.newSuperior.sizeTagged(TagModifyDNRequestNewSuperior)
+	}
+	size += sizeTagAndLength(TagModifyDNRequest, size)
+	return
+}
--- a/goldap/modify_dn_response.go
+++ b/goldap/modify_dn_response.go
@ -0,0 +1,28 @@
+package message
+
+import "fmt"
+
+//
+//        ModifyDNResponse ::= [APPLICATION 13] LDAPResult
+func readModifyDNResponse(bytes *Bytes) (ret ModifyDNResponse, err error) {
+	var res LDAPResult
+	res, err = readTaggedLDAPResult(bytes, classApplication, TagModifyDNResponse)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readModifyDNResponse:\n%s", err.Error())}
+		return
+	}
+	ret = ModifyDNResponse(res)
+	return
+}
+
+//
+//        ModifyDNResponse ::= [APPLICATION 13] LDAPResult
+func (m ModifyDNResponse) write(bytes *Bytes) int {
+	return LDAPResult(m).writeTagged(bytes, classApplication, TagModifyDNResponse)
+}
+
+//
+//        ModifyDNResponse ::= [APPLICATION 13] LDAPResult
+func (m ModifyDNResponse) size() int {
+	return LDAPResult(m).sizeTagged(TagModifyDNResponse)
+}
--- a/goldap/modify_request.go
+++ b/goldap/modify_request.go
@ -0,0 +1,89 @@
+package message
+
+import "fmt"
+
+//
+//        ModifyRequest ::= [APPLICATION 6] SEQUENCE {
+//             object          LDAPDN,
+//             changes         SEQUENCE OF change SEQUENCE {
+//                  operation       ENUMERATED {
+//                       add     (0),
+//                       delete  (1),
+//                       replace (2),
+//                       ...  },
+//                  modification    PartialAttribute } }
+func readModifyRequest(bytes *Bytes) (ret ModifyRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagModifyRequest, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readModifyRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (m *ModifyRequest) readComponents(bytes *Bytes) (err error) {
+	m.object, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, m.readChanges)
+	return
+}
+func (m *ModifyRequest) readChanges(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var c ModifyRequestChange
+		c, err = readModifyRequestChange(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readChanges:\n%s", err.Error())}
+			return
+		}
+		m.changes = append(m.changes, c)
+	}
+	return
+}
+
+//
+//        ModifyRequest ::= [APPLICATION 6] SEQUENCE {
+//             object          LDAPDN,
+//             changes         SEQUENCE OF change SEQUENCE {
+//                  operation       ENUMERATED {
+//                       add     (0),
+//                       delete  (1),
+//                       replace (2),
+//                       ...  },
+//                  modification    PartialAttribute } }
+func (m ModifyRequest) write(bytes *Bytes) (size int) {
+	for i := len(m.changes) - 1; i >= 0; i-- {
+		size += m.changes[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	size += m.object.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagModifyRequest, size)
+	return
+}
+
+//
+//        ModifyRequest ::= [APPLICATION 6] SEQUENCE {
+//             object          LDAPDN,
+//             changes         SEQUENCE OF change SEQUENCE {
+//                  operation       ENUMERATED {
+//                       add     (0),
+//                       delete  (1),
+//                       replace (2),
+//                       ...  },
+//                  modification    PartialAttribute } }
+func (m ModifyRequest) size() (size int) {
+	for _, change := range m.changes {
+		size += change.size()
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	size += m.object.size()
+	size += sizeTagAndLength(TagModifyRequest, size)
+	return
+}
+func (m *ModifyRequest) Object() LDAPDN {
+	return m.object
+}
+func (m *ModifyRequest) Changes() []ModifyRequestChange {
+	return m.changes
+}
--- a/goldap/modify_request_change.go
+++ b/goldap/modify_request_change.go
@ -0,0 +1,43 @@
+package message
+
+import "fmt"
+
+func readModifyRequestChange(bytes *Bytes) (ret ModifyRequestChange, err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readModifyRequestChange:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (m *ModifyRequestChange) readComponents(bytes *Bytes) (err error) {
+	m.operation, err = readENUMERATED(bytes, EnumeratedModifyRequestChangeOperation)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	m.modification, err = readPartialAttribute(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (m ModifyRequestChange) write(bytes *Bytes) (size int) {
+	size += m.modification.write(bytes)
+	size += m.operation.write(bytes)
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+func (m ModifyRequestChange) size() (size int) {
+	size += m.operation.size()
+	size += m.modification.size()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+func (m *ModifyRequestChange) Operation() ENUMERATED {
+	return m.operation
+}
+func (m *ModifyRequestChange) Modification() *PartialAttribute {
+	return &m.modification
+}
--- a/goldap/modify_response.go
+++ b/goldap/modify_response.go
@ -0,0 +1,36 @@
+package message
+
+import "fmt"
+
+//
+//        ModifyResponse ::= [APPLICATION 7] LDAPResult
+func readModifyResponse(bytes *Bytes) (ret ModifyResponse, err error) {
+	var res LDAPResult
+	res, err = readTaggedLDAPResult(bytes, classApplication, TagModifyResponse)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readModifyResponse:\n%s", err.Error())}
+		return
+	}
+	ret = ModifyResponse(res)
+	return
+}
+func (l LDAPResult) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	size += l.writeComponents(bytes)
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+//
+//        ModifyResponse ::= [APPLICATION 7] LDAPResult
+func (m ModifyResponse) write(bytes *Bytes) int {
+	return LDAPResult(m).writeTagged(bytes, classApplication, TagModifyResponse)
+}
+
+//
+//        ModifyResponse ::= [APPLICATION 7] LDAPResult
+func (m ModifyResponse) size() int {
+	return LDAPResult(m).sizeTagged(TagModifyResponse)
+}
+func (l *ModifyResponse) SetResultCode(code int) {
+	l.resultCode = ENUMERATED(code)
+}
--- a/goldap/octetstring.go
+++ b/goldap/octetstring.go
@ -0,0 +1,44 @@
+package message
+
+import "fmt"
+
+func readOCTETSTRING(bytes *Bytes) (ret OCTETSTRING, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(classUniversal, tagOctetString, tagOctetString)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readOCTETSTRING:\n%s", err.Error())}
+		return
+	}
+	ret = OCTETSTRING(value.([]byte))
+	return
+}
+
+func readTaggedOCTETSTRING(bytes *Bytes, class int, tag int) (ret OCTETSTRING, err error) {
+	var value interface{}
+	value, err = bytes.ReadPrimitiveSubBytes(class, tag, tagOctetString)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedOCTETSTRING:\n%s", err.Error())}
+		return
+	}
+	ret = OCTETSTRING(value.([]byte))
+	return
+}
+func (o OCTETSTRING) Pointer() *OCTETSTRING { return &o }
+func (o OCTETSTRING) write(bytes *Bytes) int {
+	return bytes.WritePrimitiveSubBytes(classUniversal, tagOctetString, o)
+}
+func (o OCTETSTRING) writeTagged(bytes *Bytes, class int, tag int) int {
+	return bytes.WritePrimitiveSubBytes(class, tag, o)
+}
+func (o OCTETSTRING) size() int {
+	return SizePrimitiveSubBytes(tagOctetString, o)
+}
+func (o OCTETSTRING) sizeTagged(tag int) int {
+	return SizePrimitiveSubBytes(tag, o)
+}
+func (l OCTETSTRING) String() string {
+	return string(l)
+}
+func (l OCTETSTRING) Bytes() []byte {
+	return []byte(l)
+}
--- a/goldap/oid.go
+++ b/goldap/oid.go
@ -0,0 +1,50 @@
+package message
+
+import "fmt"
+
+//
+//
+//        LDAPOID ::= OCTET STRING -- Constrained to <numericoid>
+//                                 -- [RFC4512]
+
+func (l LDAPOID) String() string {
+	return string(l)
+}
+
+func (l LDAPOID) Bytes() []byte {
+	return []byte(l)
+}
+
+func (l LDAPOID) Pointer() *LDAPOID { return &l }
+
+func readTaggedLDAPOID(bytes *Bytes, class int, tag int) (ret LDAPOID, err error) {
+	var octetstring OCTETSTRING
+	octetstring, err = readTaggedOCTETSTRING(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedLDAPOID:\n%s", err.Error())}
+		return
+	}
+	// @TODO: check RFC4512 for <numericoid>
+	ret = LDAPOID(octetstring)
+	return
+}
+
+func readLDAPOID(bytes *Bytes) (ret LDAPOID, err error) {
+	return readTaggedLDAPOID(bytes, classUniversal, tagOctetString)
+}
+
+func (l LDAPOID) write(bytes *Bytes) int {
+	return OCTETSTRING(l).write(bytes)
+}
+
+func (l LDAPOID) writeTagged(bytes *Bytes, class int, tag int) int {
+	return OCTETSTRING(l).writeTagged(bytes, class, tag)
+}
+
+func (l LDAPOID) size() int {
+	return OCTETSTRING(l).size()
+}
+
+func (l LDAPOID) sizeTagged(tag int) int {
+	return OCTETSTRING(l).sizeTagged(tag)
+}
--- a/goldap/partial_attribute.go
+++ b/goldap/partial_attribute.go
@ -0,0 +1,76 @@
+package message
+
+import "fmt"
+
+//
+//        PartialAttribute ::= SEQUENCE {
+//             type       AttributeDescription,
+//             vals       SET OF value AttributeValue }
+func readPartialAttribute(bytes *Bytes) (ret PartialAttribute, err error) {
+	ret = PartialAttribute{vals: make([]AttributeValue, 0, 10)}
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readPartialAttribute:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (partialattribute *PartialAttribute) readComponents(bytes *Bytes) (err error) {
+	partialattribute.type_, err = readAttributeDescription(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	err = bytes.ReadSubBytes(classUniversal, tagSet, partialattribute.readValsComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (partialattribute *PartialAttribute) readValsComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var attributevalue AttributeValue
+		attributevalue, err = readAttributeValue(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readValsComponents:\n%s", err.Error())}
+			return
+		}
+		partialattribute.vals = append(partialattribute.vals, attributevalue)
+	}
+	return
+}
+
+//
+//        PartialAttribute ::= SEQUENCE {
+//             type       AttributeDescription,
+//             vals       SET OF value AttributeValue }
+func (p PartialAttribute) write(bytes *Bytes) (size int) {
+	for i := len(p.vals) - 1; i >= 0; i-- {
+		size += p.vals[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSet, size)
+	size += p.type_.write(bytes)
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+
+//
+//        PartialAttribute ::= SEQUENCE {
+//             type       AttributeDescription,
+//             vals       SET OF value AttributeValue }
+func (p PartialAttribute) size() (size int) {
+	for _, value := range p.vals {
+		size += value.size()
+	}
+	size += sizeTagAndLength(tagSet, size)
+	size += p.type_.size()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+func (p *PartialAttribute) Type_() AttributeDescription {
+	return p.type_
+}
+func (p *PartialAttribute) Vals() []AttributeValue {
+	return p.vals
+}
--- a/goldap/partial_attribute_list.go
+++ b/goldap/partial_attribute_list.go
@ -0,0 +1,53 @@
+package message
+
+import "fmt"
+
+//
+//        PartialAttributeList ::= SEQUENCE OF
+//                             partialAttribute PartialAttribute
+func readPartialAttributeList(bytes *Bytes) (ret PartialAttributeList, err error) {
+	ret = PartialAttributeList(make([]PartialAttribute, 0, 10))
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readPartialAttributeList:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (partialattributelist *PartialAttributeList) readComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var partialattribute PartialAttribute
+		partialattribute, err = readPartialAttribute(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		*partialattributelist = append(*partialattributelist, partialattribute)
+	}
+	return
+}
+
+//
+//        PartialAttributeList ::= SEQUENCE OF
+//                             partialAttribute PartialAttribute
+func (p PartialAttributeList) write(bytes *Bytes) (size int) {
+	for i := len(p) - 1; i >= 0; i-- {
+		size += p[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+
+//
+//        PartialAttributeList ::= SEQUENCE OF
+//                             partialAttribute PartialAttribute
+func (p PartialAttributeList) size() (size int) {
+	for _, att := range p {
+		size += att.size()
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+func (p *PartialAttributeList) add(a PartialAttribute) {
+	*p = append(*p, a)
+}
--- a/goldap/protocol_op.go
+++ b/goldap/protocol_op.go
@ -0,0 +1,63 @@
+package message
+
+import "fmt"
+
+func readProtocolOp(bytes *Bytes) (ret ProtocolOp, err error) {
+	tagAndLength, err := bytes.PreviewTagAndLength()
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readProtocolOp:\n%s", err.Error())}
+		return
+	}
+	switch tagAndLength.Tag {
+	case TagBindRequest:
+		ret, err = readBindRequest(bytes)
+	case TagBindResponse:
+		ret, err = readBindResponse(bytes)
+	case TagUnbindRequest:
+		ret, err = readUnbindRequest(bytes)
+	case TagSearchRequest:
+		ret, err = readSearchRequest(bytes)
+	case TagSearchResultEntry:
+		ret, err = readSearchResultEntry(bytes)
+	case TagSearchResultDone:
+		ret, err = readSearchResultDone(bytes)
+	case TagSearchResultReference:
+		ret, err = readSearchResultReference(bytes)
+	case TagModifyRequest:
+		ret, err = readModifyRequest(bytes)
+	case TagModifyResponse:
+		ret, err = readModifyResponse(bytes)
+	case TagAddRequest:
+		ret, err = readAddRequest(bytes)
+	case TagAddResponse:
+		ret, err = readAddResponse(bytes)
+	case TagDelRequest:
+		ret, err = readDelRequest(bytes)
+	case TagDelResponse:
+		ret, err = readDelResponse(bytes)
+	case TagModifyDNRequest:
+		ret, err = readModifyDNRequest(bytes)
+	case TagModifyDNResponse:
+		ret, err = readModifyDNResponse(bytes)
+	case TagCompareRequest:
+		ret, err = readCompareRequest(bytes)
+	case TagCompareResponse:
+		ret, err = readCompareResponse(bytes)
+	case TagAbandonRequest:
+		ret, err = readAbandonRequest(bytes)
+	case TagExtendedRequest:
+		ret, err = readExtendedRequest(bytes)
+	case TagExtendedResponse:
+		ret, err = readExtendedResponse(bytes)
+	case TagIntermediateResponse:
+		ret, err = readIntermediateResponse(bytes)
+	default:
+		err = LdapError{fmt.Sprintf("readProtocolOp: invalid tag value %d for protocolOp", tagAndLength.Tag)}
+		return
+	}
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readProtocolOp:\n%s", err.Error())}
+		return
+	}
+	return
+}
--- a/goldap/read.go
+++ b/goldap/read.go
@ -0,0 +1,18 @@
+package message
+
+import (
+	"fmt"
+)
+
+func ReadLDAPMessage(bytes *Bytes) (message LDAPMessage, err error) {
+	err = bytes.ReadSubBytes(classUniversal, tagSequence, message.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("ReadLDAPMessage:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+//
+//        END
+//
--- a/goldap/read_error_test.go
+++ b/goldap/read_error_test.go
--- a/goldap/read_test.go
+++ b/goldap/read_test.go
--- a/goldap/referral.go
+++ b/goldap/referral.go
@ -0,0 +1,50 @@
+package message
+
+import "fmt"
+
+//
+//        Referral ::= SEQUENCE SIZE (1..MAX) OF uri URI
+func readTaggedReferral(bytes *Bytes, class int, tag int) (referral Referral, err error) {
+	err = bytes.ReadSubBytes(class, tag, referral.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedReferral:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (referral *Referral) readComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var uri URI
+		uri, err = readURI(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		*referral = append(*referral, uri)
+	}
+	if len(*referral) == 0 {
+		return LdapError{"readComponents: expecting at least one URI"}
+	}
+	return
+}
+func (referral Referral) Pointer() *Referral { return &referral }
+
+//
+//        Referral ::= SEQUENCE SIZE (1..MAX) OF uri URI
+func (r Referral) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	for i := len(r) - 1; i >= 0; i-- {
+		size += r[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+//
+//        Referral ::= SEQUENCE SIZE (1..MAX) OF uri URI
+func (r Referral) sizeTagged(tag int) (size int) {
+	for _, uri := range r {
+		size += uri.size()
+	}
+	size += sizeTagAndLength(tag, size)
+	return
+}
--- a/goldap/relative_ldap_dn.go
+++ b/goldap/relative_ldap_dn.go
@ -0,0 +1,15 @@
+package message
+
+//
+//        RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
+//                                      -- [RFC4514]
+func (r RelativeLDAPDN) write(bytes *Bytes) int {
+	return LDAPString(r).write(bytes)
+}
+
+//
+//        RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
+//                                      -- [RFC4514]
+func (r RelativeLDAPDN) size() int {
+	return LDAPString(r).size()
+}
--- a/goldap/result.go
+++ b/goldap/result.go
@ -0,0 +1,282 @@
+package message
+
+import "fmt"
+
+//
+//        LDAPResult ::= SEQUENCE {
+//             resultCode         ENUMERATED {
+//                  success                      (0),
+//                  operationsError              (1),
+//                  protocolError                (2),
+//                  timeLimitExceeded            (3),
+//                  sizeLimitExceeded            (4),
+//                  compareFalse                 (5),
+//                  compareTrue                  (6),
+//                  authMethodNotSupported       (7),
+//                  strongerAuthRequired         (8),
+//                       -- 9 reserved --
+//                  referral                     (10),
+//                  adminLimitExceeded           (11),
+//                  unavailableCriticalExtension (12),
+//                  confidentialityRequired      (13),
+//                  saslBindInProgress           (14),
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 55]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//                  noSuchAttribute              (16),
+//                  undefinedAttributeType       (17),
+//                  inappropriateMatching        (18),
+//                  constraintViolation          (19),
+//                  attributeOrValueExists       (20),
+//                  invalidAttributeSyntax       (21),
+//                       -- 22-31 unused --
+//                  noSuchObject                 (32),
+//                  aliasProblem                 (33),
+//                  invalidDNSyntax              (34),
+//                       -- 35 reserved for undefined isLeaf --
+//                  aliasDereferencingProblem    (36),
+//                       -- 37-47 unused --
+//                  inappropriateAuthentication  (48),
+//                  invalidCredentials           (49),
+//                  insufficientAccessRights     (50),
+//                  busy                         (51),
+//                  unavailable                  (52),
+//                  unwillingToPerform           (53),
+//                  loopDetect                   (54),
+//                       -- 55-63 unused --
+//                  namingViolation              (64),
+//                  objectClassViolation         (65),
+//                  notAllowedOnNonLeaf          (66),
+//                  notAllowedOnRDN              (67),
+//                  entryAlreadyExists           (68),
+//                  objectClassModsProhibited    (69),
+//                       -- 70 reserved for CLDAP --
+//                  affectsMultipleDSAs          (71),
+//                       -- 72-79 unused --
+//                  other                        (80),
+//                  ...  },
+//             matchedDN          LDAPDN,
+//             diagnosticMessage  LDAPString,
+//             referral           [3] Referral OPTIONAL }
+func readTaggedLDAPResult(bytes *Bytes, class int, tag int) (ret LDAPResult, err error) {
+	err = bytes.ReadSubBytes(class, tag, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedLDAPResult:\n%s", err.Error())}
+	}
+	return
+}
+func readLDAPResult(bytes *Bytes) (ldapresult LDAPResult, err error) {
+	return readTaggedLDAPResult(bytes, classUniversal, tagSequence)
+}
+func (ldapresult *LDAPResult) readComponents(bytes *Bytes) (err error) {
+	ldapresult.resultCode, err = readENUMERATED(bytes, EnumeratedLDAPResultCode)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	ldapresult.matchedDN, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	ldapresult.diagnosticMessage, err = readLDAPString(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if bytes.HasMoreData() {
+		var tag TagAndLength
+		tag, err = bytes.PreviewTagAndLength()
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		if tag.Tag == TagLDAPResultReferral {
+			var referral Referral
+			referral, err = readTaggedReferral(bytes, classContextSpecific, TagLDAPResultReferral)
+			if err != nil {
+				err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+				return
+			}
+			ldapresult.referral = referral.Pointer()
+		}
+	}
+	return
+}
+
+//
+//        LDAPResult ::= SEQUENCE {
+//             resultCode         ENUMERATED {
+//                  success                      (0),
+//                  operationsError              (1),
+//                  protocolError                (2),
+//                  timeLimitExceeded            (3),
+//                  sizeLimitExceeded            (4),
+//                  compareFalse                 (5),
+//                  compareTrue                  (6),
+//                  authMethodNotSupported       (7),
+//                  strongerAuthRequired         (8),
+//                       -- 9 reserved --
+//                  referral                     (10),
+//                  adminLimitExceeded           (11),
+//                  unavailableCriticalExtension (12),
+//                  confidentialityRequired      (13),
+//                  saslBindInProgress           (14),
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 55]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//                  noSuchAttribute              (16),
+//                  undefinedAttributeType       (17),
+//                  inappropriateMatching        (18),
+//                  constraintViolation          (19),
+//                  attributeOrValueExists       (20),
+//                  invalidAttributeSyntax       (21),
+//                       -- 22-31 unused --
+//                  noSuchObject                 (32),
+//                  aliasProblem                 (33),
+//                  invalidDNSyntax              (34),
+//                       -- 35 reserved for undefined isLeaf --
+//                  aliasDereferencingProblem    (36),
+//                       -- 37-47 unused --
+//                  inappropriateAuthentication  (48),
+//                  invalidCredentials           (49),
+//                  insufficientAccessRights     (50),
+//                  busy                         (51),
+//                  unavailable                  (52),
+//                  unwillingToPerform           (53),
+//                  loopDetect                   (54),
+//                       -- 55-63 unused --
+//                  namingViolation              (64),
+//                  objectClassViolation         (65),
+//                  notAllowedOnNonLeaf          (66),
+//                  notAllowedOnRDN              (67),
+//                  entryAlreadyExists           (68),
+//                  objectClassModsProhibited    (69),
+//                       -- 70 reserved for CLDAP --
+//                  affectsMultipleDSAs          (71),
+//                       -- 72-79 unused --
+//                  other                        (80),
+//                  ...  },
+//             matchedDN          LDAPDN,
+//             diagnosticMessage  LDAPString,
+//             referral           [3] Referral OPTIONAL }
+func (l LDAPResult) write(bytes *Bytes) (size int) {
+	size += l.writeComponents(bytes)
+	size += bytes.WriteTagAndLength(classUniversal, isCompound, tagSequence, size)
+	return
+}
+func (l LDAPResult) writeComponents(bytes *Bytes) (size int) {
+	if l.referral != nil {
+		size += l.referral.writeTagged(bytes, classContextSpecific, TagLDAPResultReferral)
+	}
+	size += l.diagnosticMessage.write(bytes)
+	size += l.matchedDN.write(bytes)
+	size += l.resultCode.write(bytes)
+	return
+}
+
+//
+//        LDAPResult ::= SEQUENCE {
+//             resultCode         ENUMERATED {
+//                  success                      (0),
+//                  operationsError              (1),
+//                  protocolError                (2),
+//                  timeLimitExceeded            (3),
+//                  sizeLimitExceeded            (4),
+//                  compareFalse                 (5),
+//                  compareTrue                  (6),
+//                  authMethodNotSupported       (7),
+//                  strongerAuthRequired         (8),
+//                       -- 9 reserved --
+//                  referral                     (10),
+//                  adminLimitExceeded           (11),
+//                  unavailableCriticalExtension (12),
+//                  confidentialityRequired      (13),
+//                  saslBindInProgress           (14),
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 55]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//                  noSuchAttribute              (16),
+//                  undefinedAttributeType       (17),
+//                  inappropriateMatching        (18),
+//                  constraintViolation          (19),
+//                  attributeOrValueExists       (20),
+//                  invalidAttributeSyntax       (21),
+//                       -- 22-31 unused --
+//                  noSuchObject                 (32),
+//                  aliasProblem                 (33),
+//                  invalidDNSyntax              (34),
+//                       -- 35 reserved for undefined isLeaf --
+//                  aliasDereferencingProblem    (36),
+//                       -- 37-47 unused --
+//                  inappropriateAuthentication  (48),
+//                  invalidCredentials           (49),
+//                  insufficientAccessRights     (50),
+//                  busy                         (51),
+//                  unavailable                  (52),
+//                  unwillingToPerform           (53),
+//                  loopDetect                   (54),
+//                       -- 55-63 unused --
+//                  namingViolation              (64),
+//                  objectClassViolation         (65),
+//                  notAllowedOnNonLeaf          (66),
+//                  notAllowedOnRDN              (67),
+//                  entryAlreadyExists           (68),
+//                  objectClassModsProhibited    (69),
+//                       -- 70 reserved for CLDAP --
+//                  affectsMultipleDSAs          (71),
+//                       -- 72-79 unused --
+//                  other                        (80),
+//                  ...  },
+//             matchedDN          LDAPDN,
+//             diagnosticMessage  LDAPString,
+//             referral           [3] Referral OPTIONAL }
+func (l LDAPResult) size() (size int) {
+	size += l.sizeComponents()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+func (l LDAPResult) sizeTagged(tag int) (size int) {
+	size += l.sizeComponents()
+	size += sizeTagAndLength(tag, size)
+	return
+}
+func (l LDAPResult) sizeComponents() (size int) {
+	if l.referral != nil {
+		size += l.referral.sizeTagged(TagLDAPResultReferral)
+	}
+	size += l.diagnosticMessage.size()
+	size += l.matchedDN.size()
+	size += l.resultCode.size()
+	return
+}
+func (l *LDAPResult) SetResultCode(code int) {
+	l.resultCode = ENUMERATED(code)
+}
+func (l *LDAPResult) SeMatchedDN(code string) {
+	l.matchedDN = LDAPDN(code)
+}
+func (l *LDAPResult) SetDiagnosticMessage(code string) {
+	l.diagnosticMessage = LDAPString(code)
+}
+func (l *LDAPResult) SetReferral(r *Referral) {
+	l.referral = r
+}
--- a/goldap/sasl_credentials.go
+++ b/goldap/sasl_credentials.go
@ -0,0 +1,63 @@
+package message
+
+import "fmt"
+
+//
+//        SaslCredentials ::= SEQUENCE {
+//             mechanism               LDAPString,
+//             credentials             OCTET STRING OPTIONAL }
+//
+func readSaslCredentials(bytes *Bytes) (authentication SaslCredentials, err error) {
+	authentication = SaslCredentials{}
+	err = bytes.ReadSubBytes(classContextSpecific, TagAuthenticationChoiceSaslCredentials, authentication.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readSaslCredentials:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (authentication *SaslCredentials) readComponents(bytes *Bytes) (err error) {
+	authentication.mechanism, err = readLDAPString(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	if bytes.HasMoreData() {
+		var credentials OCTETSTRING
+		credentials, err = readOCTETSTRING(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		authentication.credentials = credentials.Pointer()
+	}
+	return
+}
+
+//
+//        SaslCredentials ::= SEQUENCE {
+//             mechanism               LDAPString,
+//             credentials             OCTET STRING OPTIONAL }
+//
+func (s SaslCredentials) writeTagged(bytes *Bytes, class int, tag int) (size int) {
+	if s.credentials != nil {
+		size += s.credentials.write(bytes)
+	}
+	size += s.mechanism.write(bytes)
+	size += bytes.WriteTagAndLength(class, isCompound, tag, size)
+	return
+}
+
+//
+//        SaslCredentials ::= SEQUENCE {
+//             mechanism               LDAPString,
+//             credentials             OCTET STRING OPTIONAL }
+//
+func (s SaslCredentials) sizeTagged(tag int) (size int) {
+	if s.credentials != nil {
+		size += s.credentials.size()
+	}
+	size += s.mechanism.size()
+	size += sizeTagAndLength(tag, size)
+	return
+}
--- a/goldap/search_request.go
+++ b/goldap/search_request.go
@ -0,0 +1,246 @@
+package message
+
+import (
+	"errors"
+	"fmt"
+)
+
+//
+//        SearchRequest ::= [APPLICATION 3] SEQUENCE {
+//             baseObject      LDAPDN,
+//             scope           ENUMERATED {
+//                  baseObject              (0),
+//                  singleLevel             (1),
+//                  wholeSubtree            (2),
+//                  ...  },
+//             derefAliases    ENUMERATED {
+//                  neverDerefAliases       (0),
+//                  derefInSearching        (1),
+//                  derefFindingBaseObj     (2),
+//                  derefAlways             (3) },
+//             sizeLimit       INTEGER (0 ..  maxInt),
+//             timeLimit       INTEGER (0 ..  maxInt),
+//             typesOnly       BOOLEAN,
+//             filter          Filter,
+//             attributes      AttributeSelection }
+func readSearchRequest(bytes *Bytes) (searchrequest SearchRequest, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagSearchRequest, searchrequest.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readSearchRequest:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (searchrequest *SearchRequest) readComponents(bytes *Bytes) (err error) {
+	searchrequest.baseObject, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.scope, err = readENUMERATED(bytes, EnumeratedSearchRequestScope)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.derefAliases, err = readENUMERATED(bytes, EnumeratedSearchRequestDerefAliases)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.sizeLimit, err = readPositiveINTEGER(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.timeLimit, err = readPositiveINTEGER(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.typesOnly, err = readBOOLEAN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.filter, err = readFilter(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchrequest.attributes, err = readAttributeSelection(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+//
+//        SearchRequest ::= [APPLICATION 3] SEQUENCE {
+//             baseObject      LDAPDN,
+//             scope           ENUMERATED {
+//                  baseObject              (0),
+//                  singleLevel             (1),
+//                  wholeSubtree            (2),
+//                  ...  },
+//             derefAliases    ENUMERATED {
+//                  neverDerefAliases       (0),
+//                  derefInSearching        (1),
+//                  derefFindingBaseObj     (2),
+//                  derefAlways             (3) },
+//             sizeLimit       INTEGER (0 ..  maxInt),
+//             timeLimit       INTEGER (0 ..  maxInt),
+//             typesOnly       BOOLEAN,
+//             filter          Filter,
+//             attributes      AttributeSelection }
+func (s SearchRequest) write(bytes *Bytes) (size int) {
+	size += s.attributes.write(bytes)
+	size += s.filter.write(bytes)
+	size += s.typesOnly.write(bytes)
+	size += s.timeLimit.write(bytes)
+	size += s.sizeLimit.write(bytes)
+	size += s.derefAliases.write(bytes)
+	size += s.scope.write(bytes)
+	size += s.baseObject.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagSearchRequest, size)
+	return
+}
+
+//
+//        SearchRequest ::= [APPLICATION 3] SEQUENCE {
+//             baseObject      LDAPDN,
+//             scope           ENUMERATED {
+//                  baseObject              (0),
+//                  singleLevel             (1),
+//                  wholeSubtree            (2),
+//                  ...  },
+//             derefAliases    ENUMERATED {
+//                  neverDerefAliases       (0),
+//                  derefInSearching        (1),
+//                  derefFindingBaseObj     (2),
+//                  derefAlways             (3) },
+//             sizeLimit       INTEGER (0 ..  maxInt),
+//             timeLimit       INTEGER (0 ..  maxInt),
+//             typesOnly       BOOLEAN,
+//             filter          Filter,
+//             attributes      AttributeSelection }
+func (s SearchRequest) size() (size int) {
+	size += s.baseObject.size()
+	size += s.scope.size()
+	size += s.derefAliases.size()
+	size += s.sizeLimit.size()
+	size += s.timeLimit.size()
+	size += s.typesOnly.size()
+	size += s.filter.size()
+	size += s.attributes.size()
+	size += sizeTagAndLength(TagSearchRequest, size)
+	return
+}
+func (s *SearchRequest) BaseObject() LDAPDN {
+	return s.baseObject
+}
+func (s *SearchRequest) Scope() ENUMERATED {
+	return s.scope
+}
+func (s *SearchRequest) DerefAliases() ENUMERATED {
+	return s.derefAliases
+}
+func (s *SearchRequest) SizeLimit() INTEGER {
+	return s.sizeLimit
+}
+func (s *SearchRequest) TimeLimit() INTEGER {
+	return s.timeLimit
+}
+func (s *SearchRequest) TypesOnly() BOOLEAN {
+	return s.typesOnly
+}
+func (s *SearchRequest) Attributes() AttributeSelection {
+	return s.attributes
+}
+func (s *SearchRequest) Filter() Filter {
+	return s.filter
+}
+func (s *SearchRequest) FilterString() string {
+	str, _ := s.decompileFilter(s.Filter())
+	return str
+}
+func (s *SearchRequest) decompileFilter(packet Filter) (ret string, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = errors.New("error decompiling filter")
+		}
+	}()
+
+	ret = "("
+	err = nil
+	childStr := ""
+
+	switch f := packet.(type) {
+	case FilterAnd:
+		ret += "&"
+		for _, child := range f {
+			childStr, err = s.decompileFilter(child)
+			if err != nil {
+				return
+			}
+			ret += childStr
+		}
+	case FilterOr:
+		ret += "|"
+		for _, child := range f {
+			childStr, err = s.decompileFilter(child)
+			if err != nil {
+				return
+			}
+			ret += childStr
+		}
+	case FilterNot:
+		ret += "!"
+		childStr, err = s.decompileFilter(f.Filter)
+		if err != nil {
+			return
+		}
+		ret += childStr
+
+	case FilterSubstrings:
+		ret += string(f.Type_())
+		ret += "="
+		for _, fs := range f.Substrings() {
+			switch fsv := fs.(type) {
+			case SubstringInitial:
+				ret += string(fsv) + "*"
+			case SubstringAny:
+				ret += "*" + string(fsv) + "*"
+			case SubstringFinal:
+				ret += "*" + string(fsv)
+			}
+		}
+	case FilterEqualityMatch:
+		ret += string(f.AttributeDesc())
+		ret += "="
+		ret += string(f.AssertionValue())
+	case FilterGreaterOrEqual:
+		ret += string(f.AttributeDesc())
+		ret += ">="
+		ret += string(f.AssertionValue())
+	case FilterLessOrEqual:
+		ret += string(f.AttributeDesc())
+		ret += "<="
+		ret += string(f.AssertionValue())
+	case FilterPresent:
+		// if 0 == len(packet.Children) {
+		// 	ret += ber.DecodeString(packet.Data.Bytes())
+		// } else {
+		// 	ret += ber.DecodeString(packet.Children[0].Data.Bytes())
+		// }
+		ret += string(f)
+		ret += "=*"
+	case FilterApproxMatch:
+		ret += string(f.AttributeDesc())
+		ret += "~="
+		ret += string(f.AssertionValue())
+	}
+
+	ret += ")"
+	return
+}
--- a/goldap/search_result_done.go
+++ b/goldap/search_result_done.go
@ -0,0 +1,31 @@
+package message
+
+import "fmt"
+
+//
+//        SearchResultDone ::= [APPLICATION 5] LDAPResult
+func readSearchResultDone(bytes *Bytes) (ret SearchResultDone, err error) {
+	var ldapresult LDAPResult
+	ldapresult, err = readTaggedLDAPResult(bytes, classApplication, TagSearchResultDone)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readSearchResultDone:\n%s", err.Error())}
+		return
+	}
+	ret = SearchResultDone(ldapresult)
+	return
+}
+
+//
+//        SearchResultDone ::= [APPLICATION 5] LDAPResult
+func (s SearchResultDone) write(bytes *Bytes) int {
+	return LDAPResult(s).writeTagged(bytes, classApplication, TagSearchResultDone)
+}
+
+//
+//        SearchResultDone ::= [APPLICATION 5] LDAPResult
+func (s SearchResultDone) size() int {
+	return LDAPResult(s).sizeTagged(TagSearchResultDone)
+}
+func (l *SearchResultDone) SetResultCode(code int) {
+	l.resultCode = ENUMERATED(code)
+}
--- a/goldap/search_result_entry.go
+++ b/goldap/search_result_entry.go
@ -0,0 +1,58 @@
+package message
+
+import "fmt"
+
+//
+//        SearchResultEntry ::= [APPLICATION 4] SEQUENCE {
+//             objectName      LDAPDN,
+//             attributes      PartialAttributeList }
+func readSearchResultEntry(bytes *Bytes) (searchresultentry SearchResultEntry, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagSearchResultEntry, searchresultentry.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readSearchResultEntry:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (searchresultentry *SearchResultEntry) readComponents(bytes *Bytes) (err error) {
+	searchresultentry.objectName, err = readLDAPDN(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	searchresultentry.attributes, err = readPartialAttributeList(bytes)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+		return
+	}
+	return
+}
+
+//
+//        SearchResultEntry ::= [APPLICATION 4] SEQUENCE {
+//             objectName      LDAPDN,
+//             attributes      PartialAttributeList }
+func (s SearchResultEntry) write(bytes *Bytes) (size int) {
+	size += s.attributes.write(bytes)
+	size += s.objectName.write(bytes)
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagSearchResultEntry, size)
+	return
+}
+
+//
+//        SearchResultEntry ::= [APPLICATION 4] SEQUENCE {
+//             objectName      LDAPDN,
+//             attributes      PartialAttributeList }
+func (s SearchResultEntry) size() (size int) {
+	size += s.objectName.size()
+	size += s.attributes.size()
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
+func (s *SearchResultEntry) SetObjectName(on string) {
+	s.objectName = LDAPDN(on)
+}
+func (s *SearchResultEntry) AddAttribute(name AttributeDescription, values ...AttributeValue) {
+	var ea = PartialAttribute{type_: name, vals: values}
+	s.attributes.add(ea)
+}
--- a/goldap/search_result_reference.go
+++ b/goldap/search_result_reference.go
@ -0,0 +1,53 @@
+package message
+
+import "fmt"
+
+//
+//        SearchResultReference ::= [APPLICATION 19] SEQUENCE
+//                                  SIZE (1..MAX) OF uri URI
+func readSearchResultReference(bytes *Bytes) (ret SearchResultReference, err error) {
+	err = bytes.ReadSubBytes(classApplication, TagSearchResultReference, ret.readComponents)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readSearchResultReference:\n%s", err.Error())}
+		return
+	}
+	return
+}
+func (s *SearchResultReference) readComponents(bytes *Bytes) (err error) {
+	for bytes.HasMoreData() {
+		var uri URI
+		uri, err = readURI(bytes)
+		if err != nil {
+			err = LdapError{fmt.Sprintf("readComponents:\n%s", err.Error())}
+			return
+		}
+		*s = append(*s, uri)
+	}
+	if len(*s) == 0 {
+		err = LdapError{"readComponents: expecting at least one URI"}
+		return
+	}
+	return
+}
+
+//
+//        SearchResultReference ::= [APPLICATION 19] SEQUENCE
+//                                  SIZE (1..MAX) OF uri URI
+func (s SearchResultReference) write(bytes *Bytes) (size int) {
+	for i := len(s) - 1; i >= 0; i-- {
+		size += s[i].write(bytes)
+	}
+	size += bytes.WriteTagAndLength(classApplication, isCompound, TagSearchResultReference, size)
+	return
+}
+
+//
+//        SearchResultReference ::= [APPLICATION 19] SEQUENCE
+//                                  SIZE (1..MAX) OF uri URI
+func (s SearchResultReference) size() (size int) {
+	for _, uri := range s {
+		size += uri.size()
+	}
+	size += sizeTagAndLength(tagSequence, size)
+	return
+}
--- a/goldap/size_test.go
+++ b/goldap/size_test.go
@ -0,0 +1,85 @@
+package message
+
+import (
+	"testing"
+)
+
+func TestSizeLDAPMessage(t *testing.T) {
+
+	var testData = getLDAPMessageTestData()
+	for i, test := range testData {
+		message, err := ReadLDAPMessage(&test.bytes)
+		if err != nil {
+			t.Errorf("#%d error at offset %d (%s): %s", i, test.bytes.offset, test.bytes.DumpCurrentBytes(), err)
+		}
+		size := message.size()
+		expected := len(test.bytes.bytes)
+		if size != expected {
+			t.Errorf("#%d: wrong size, GOT: %d, EXPECTED: %d", i, size, expected)
+		}
+	}
+}
+
+type tagAndLengthTestData struct {
+	tag          int
+	length       int
+	expectedSize int
+}
+
+func getSizeTagAndLengthTestData() (ret []tagAndLengthTestData) {
+	return []tagAndLengthTestData{
+		// Length between 0 and 127 are encoded on one byte
+		{
+			tag:          tagSequence,
+			length:       0,
+			expectedSize: 2,
+		},
+		{
+			tag:          tagSequence,
+			length:       127,
+			expectedSize: 2,
+		},
+		// Length between 128 and 255 are encoded on two bytes
+		{
+			tag:          tagSequence,
+			length:       128,
+			expectedSize: 3,
+		},
+		{
+			tag:          tagSequence,
+			length:       255,
+			expectedSize: 3,
+		},
+		// Length between 256 (2^8) and 65535 (2^16-1) are encoded on three bytes
+		{
+			tag:          tagSequence,
+			length:       256,
+			expectedSize: 4,
+		},
+		{
+			tag:          tagSequence,
+			length:       65535,
+			expectedSize: 4,
+		},
+		// Length between 65536 (2^16) and 16777215 (2^24-1) are encoded on four bytes
+		{
+			tag:          tagSequence,
+			length:       65536,
+			expectedSize: 5,
+		},
+		{
+			tag:          tagSequence,
+			length:       16777215,
+			expectedSize: 5,
+		},
+	}
+}
+func TestSizeTagAndLength(t *testing.T) {
+	for i, test := range getSizeTagAndLengthTestData() {
+		size := sizeTagAndLength(test.tag, test.length)
+		if test.expectedSize != size {
+			t.Errorf("#%d: wrong size, GOT: %d, EXPECTED: %d", i, size, test.expectedSize)
+		}
+	}
+
+}
--- a/goldap/string.go
+++ b/goldap/string.go
@ -0,0 +1,38 @@
+package message
+
+import "fmt"
+
+func readTaggedLDAPString(bytes *Bytes, class int, tag int) (ldapstring LDAPString, err error) {
+	var octetstring OCTETSTRING
+	octetstring, err = readTaggedOCTETSTRING(bytes, class, tag)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readTaggedLDAPString:\n%s", err.Error())}
+		return
+	}
+	ldapstring = LDAPString(octetstring)
+	return
+}
+
+//        LDAPString ::= OCTET STRING -- UTF-8 encoded,
+//                                    -- [ISO10646] characters
+func readLDAPString(bytes *Bytes) (ldapstring LDAPString, err error) {
+	return readTaggedLDAPString(bytes, classUniversal, tagOctetString)
+}
+
+//        LDAPString ::= OCTET STRING -- UTF-8 encoded,
+//                                    -- [ISO10646] characters
+func (s LDAPString) write(bytes *Bytes) int {
+	return OCTETSTRING(s).write(bytes)
+}
+func (s LDAPString) writeTagged(bytes *Bytes, class int, tag int) int {
+	return OCTETSTRING(s).writeTagged(bytes, class, tag)
+}
+
+//        LDAPString ::= OCTET STRING -- UTF-8 encoded,
+//                                    -- [ISO10646] characters
+func (s LDAPString) size() int {
+	return OCTETSTRING(s).size()
+}
+func (s LDAPString) sizeTagged(tag int) int {
+	return OCTETSTRING(s).sizeTagged(tag)
+}
--- a/goldap/struct.go
+++ b/goldap/struct.go
@ -0,0 +1,739 @@
+package message
+
+type OCTETSTRING string
+type INTEGER int32 // In this RFC the max INTEGER value is 2^31 - 1, so int32 is enough
+type BOOLEAN bool
+type ENUMERATED int32
+
+//   This appendix is normative.
+//
+//        Lightweight-Directory-Access-Protocol-V3 {1 3 6 1 1 18}
+//        -- Copyright (C) The Internet Society (2006).  This version of
+//        -- this ASN.1 module is part of RFC 4511; see the RFC itself
+//        -- for full legal notices.
+//        DEFINITIONS
+//        IMPLICIT TAGS
+//        EXTENSIBILITY IMPLIED ::=
+//
+//        BEGIN
+//
+//        LDAPMessage ::= SEQUENCE {
+//             messageID       MessageID,
+//             protocolOp      CHOICE {
+//                  bindRequest           BindRequest,
+//                  bindResponse          BindResponse,
+//                  unbindRequest         UnbindRequest,
+//                  searchRequest         SearchRequest,
+//                  searchResEntry        SearchResultEntry,
+//                  searchResDone         SearchResultDone,
+//                  searchResRef          SearchResultReference,
+//                  modifyRequest         ModifyRequest,
+//                  modifyResponse        ModifyResponse,
+//                  addRequest            AddRequest,
+//                  addResponse           AddResponse,
+//                  delRequest            DelRequest,
+//                  delResponse           DelResponse,
+//                  modDNRequest          ModifyDNRequest,
+//                  modDNResponse         ModifyDNResponse,
+//                  compareRequest        CompareRequest,
+//                  compareResponse       CompareResponse,
+//                  abandonRequest        AbandonRequest,
+//                  extendedReq           ExtendedRequest,
+//                  extendedResp          ExtendedResponse,
+//                  ...,
+//                  intermediateResponse  IntermediateResponse },
+//             controls       [0] Controls OPTIONAL }
+//
+type LDAPMessage struct {
+	messageID  MessageID
+	protocolOp ProtocolOp
+	controls   *Controls
+}
+
+const TagLDAPMessageControls = 0
+
+type ProtocolOp interface {
+	size() int
+	write(*Bytes) int
+}
+
+//        MessageID ::= INTEGER (0 ..  maxInt)
+//
+type MessageID INTEGER
+
+//        maxInt INTEGER ::= 2147483647 -- (2^^31 - 1) --
+const maxInt = INTEGER(2147483647)
+
+//
+//        LDAPString ::= OCTET STRING -- UTF-8 encoded,
+//                                    -- [ISO10646] characters
+type LDAPString OCTETSTRING
+
+//
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 54]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//        LDAPOID ::= OCTET STRING -- Constrained to <numericoid>
+//                                 -- [RFC4512]
+type LDAPOID OCTETSTRING
+
+//
+//        LDAPDN ::= LDAPString -- Constrained to <distinguishedName>
+//                              -- [RFC4514]
+type LDAPDN LDAPString
+
+//
+//        RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
+//                                      -- [RFC4514]
+type RelativeLDAPDN LDAPString
+
+//
+//        AttributeDescription ::= LDAPString
+//                                -- Constrained to <attributedescription>
+//                                -- [RFC4512]
+type AttributeDescription LDAPString
+
+//
+//        AttributeValue ::= OCTET STRING
+type AttributeValue OCTETSTRING
+
+//
+//        AttributeValueAssertion ::= SEQUENCE {
+//             attributeDesc   AttributeDescription,
+//             assertionValue  AssertionValue }
+type AttributeValueAssertion struct {
+	attributeDesc  AttributeDescription
+	assertionValue AssertionValue
+}
+
+//
+//        AssertionValue ::= OCTET STRING
+type AssertionValue OCTETSTRING
+
+//
+//        PartialAttribute ::= SEQUENCE {
+//             type       AttributeDescription,
+//             vals       SET OF value AttributeValue }
+type PartialAttribute struct {
+	type_ AttributeDescription
+	vals  []AttributeValue
+}
+
+//
+//        Attribute ::= PartialAttribute(WITH COMPONENTS {
+//             ...,
+//             vals (SIZE(1..MAX))})
+type Attribute PartialAttribute
+
+//
+//        MatchingRuleId ::= LDAPString
+type MatchingRuleId LDAPString
+
+//
+//        LDAPResult ::= SEQUENCE {
+//             resultCode         ENUMERATED {
+//                  success                      (0),
+//                  operationsError              (1),
+//                  protocolError                (2),
+//                  timeLimitExceeded            (3),
+//                  sizeLimitExceeded            (4),
+//                  compareFalse                 (5),
+//                  compareTrue                  (6),
+//                  authMethodNotSupported       (7),
+//                  strongerAuthRequired         (8),
+//                       -- 9 reserved --
+//                  referral                     (10),
+//                  adminLimitExceeded           (11),
+//                  unavailableCriticalExtension (12),
+//                  confidentialityRequired      (13),
+//                  saslBindInProgress           (14),
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 55]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//                  noSuchAttribute              (16),
+//                  undefinedAttributeType       (17),
+//                  inappropriateMatching        (18),
+//                  constraintViolation          (19),
+//                  attributeOrValueExists       (20),
+//                  invalidAttributeSyntax       (21),
+//                       -- 22-31 unused --
+//                  noSuchObject                 (32),
+//                  aliasProblem                 (33),
+//                  invalidDNSyntax              (34),
+//                       -- 35 reserved for undefined isLeaf --
+//                  aliasDereferencingProblem    (36),
+//                       -- 37-47 unused --
+//                  inappropriateAuthentication  (48),
+//                  invalidCredentials           (49),
+//                  insufficientAccessRights     (50),
+//                  busy                         (51),
+//                  unavailable                  (52),
+//                  unwillingToPerform           (53),
+//                  loopDetect                   (54),
+//                       -- 55-63 unused --
+//                  namingViolation              (64),
+//                  objectClassViolation         (65),
+//                  notAllowedOnNonLeaf          (66),
+//                  notAllowedOnRDN              (67),
+//                  entryAlreadyExists           (68),
+//                  objectClassModsProhibited    (69),
+//                       -- 70 reserved for CLDAP --
+//                  affectsMultipleDSAs          (71),
+//                       -- 72-79 unused --
+//                  other                        (80),
+//                  ...  },
+//             matchedDN          LDAPDN,
+//             diagnosticMessage  LDAPString,
+//             referral           [3] Referral OPTIONAL }
+//
+type LDAPResult struct {
+	resultCode        ENUMERATED
+	matchedDN         LDAPDN
+	diagnosticMessage LDAPString
+	referral          *Referral
+}
+
+const TagLDAPResultReferral = 3
+
+const ResultCodeSuccess = 0
+const ResultCodeOperationsError = 1
+const ResultCodeProtocolError = 2
+const ResultCodeTimeLimitExceeded = 3
+const ResultCodeSizeLimitExceeded = 4
+const ResultCodeCompareFalse = 5
+const ResultCodeCompareTrue = 6
+const ResultCodeAuthMethodNotSupported = 7
+const ResultCodeStrongerAuthRequired = 8
+const ResultCodeReferral = 10
+const ResultCodeAdminLimitExceeded = 11
+const ResultCodeUnavailableCriticalExtension = 12
+const ResultCodeConfidentialityRequired = 13
+const ResultCodeSaslBindInProgress = 14
+const ResultCodeNoSuchAttribute = 16
+const ResultCodeUndefinedAttributeType = 17
+const ResultCodeInappropriateMatching = 18
+const ResultCodeConstraintViolation = 19
+const ResultCodeAttributeOrValueExists = 20
+const ResultCodeInvalidAttributeSyntax = 21
+const ResultCodeNoSuchObject = 32
+const ResultCodeAliasProblem = 33
+const ResultCodeInvalidDNSyntax = 34
+const ResultCodeAliasDereferencingProblem = 36
+const ResultCodeInappropriateAuthentication = 48
+const ResultCodeInvalidCredentials = 49
+const ResultCodeInsufficientAccessRights = 50
+const ResultCodeBusy = 51
+const ResultCodeUnavailable = 52
+const ResultCodeUnwillingToPerform = 53
+const ResultCodeLoopDetect = 54
+const ResultCodeNamingViolation = 64
+const ResultCodeObjectClassViolation = 65
+const ResultCodeNotAllowedOnNonLeaf = 66
+const ResultCodeNotAllowedOnRDN = 67
+const ResultCodeEntryAlreadyExists = 68
+const ResultCodeObjectClassModsProhibited = 69
+const ResultCodeAffectsMultipleDSAs = 71
+const ResultCodeOther = 80
+
+var EnumeratedLDAPResultCode = map[ENUMERATED]string{
+	ResultCodeSuccess:                "success",
+	ResultCodeOperationsError:        "operationsError",
+	ResultCodeProtocolError:          "protocolError",
+	ResultCodeTimeLimitExceeded:      "timeLimitExceeded",
+	ResultCodeSizeLimitExceeded:      "sizeLimitExceeded",
+	ResultCodeCompareFalse:           "compareFalse",
+	ResultCodeCompareTrue:            "compareTrue",
+	ResultCodeAuthMethodNotSupported: "authMethodNotSupported",
+	ResultCodeStrongerAuthRequired:   "strongerAuthRequired",
+	//                       -- 9 reserved --
+	ResultCodeReferral:                     "referral",
+	ResultCodeAdminLimitExceeded:           "adminLimitExceeded",
+	ResultCodeUnavailableCriticalExtension: "unavailableCriticalExtension",
+	ResultCodeConfidentialityRequired:      "confidentialityRequired",
+	ResultCodeSaslBindInProgress:           "saslBindInProgress",
+	ResultCodeNoSuchAttribute:              "noSuchAttribute",
+	ResultCodeUndefinedAttributeType:       "undefinedAttributeType",
+	ResultCodeInappropriateMatching:        "inappropriateMatching",
+	ResultCodeConstraintViolation:          "constraintViolation",
+	ResultCodeAttributeOrValueExists:       "attributeOrValueExists",
+	ResultCodeInvalidAttributeSyntax:       "invalidAttributeSyntax",
+	//                       -- 22-31 unused --
+	ResultCodeNoSuchObject:    "noSuchObject",
+	ResultCodeAliasProblem:    "aliasProblem",
+	ResultCodeInvalidDNSyntax: "invalidDNSyntax",
+	//                       -- 35 reserved for undefined isLeaf --
+	ResultCodeAliasDereferencingProblem: "aliasDereferencingProblem",
+	//                       -- 37-47 unused --
+	ResultCodeInappropriateAuthentication: "inappropriateAuthentication",
+	ResultCodeInvalidCredentials:          "invalidCredentials",
+	ResultCodeInsufficientAccessRights:    "insufficientAccessRights",
+	ResultCodeBusy:                        "busy",
+	ResultCodeUnavailable:                 "unavailable",
+	ResultCodeUnwillingToPerform:          "unwillingToPerform",
+	ResultCodeLoopDetect:                  "loopDetect",
+	//                       -- 55-63 unused --
+	ResultCodeNamingViolation:           "namingViolation",
+	ResultCodeObjectClassViolation:      "objectClassViolation",
+	ResultCodeNotAllowedOnNonLeaf:       "notAllowedOnNonLeaf",
+	ResultCodeNotAllowedOnRDN:           "notAllowedOnRDN",
+	ResultCodeEntryAlreadyExists:        "entryAlreadyExists",
+	ResultCodeObjectClassModsProhibited: "objectClassModsProhibited",
+	//                       -- 70 reserved for CLDAP --
+	ResultCodeAffectsMultipleDSAs: "affectsMultipleDSAs",
+	//                       -- 72-79 unused --
+	ResultCodeOther: "other",
+}
+
+//        Referral ::= SEQUENCE SIZE (1..MAX) OF uri URI
+type Referral []URI
+
+//
+//        URI ::= LDAPString     -- limited to characters permitted in
+//                               -- URIs
+type URI LDAPString
+
+//
+//        Controls ::= SEQUENCE OF control Control
+type Controls []Control
+
+//
+//        Control ::= SEQUENCE {
+//             controlType             LDAPOID,
+//             criticality             BOOLEAN DEFAULT FALSE,
+//             controlValue            OCTET STRING OPTIONAL }
+type Control struct {
+	controlType  LDAPOID
+	criticality  BOOLEAN
+	controlValue *OCTETSTRING
+}
+
+//
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 56]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//        BindRequest ::= [APPLICATION 0] SEQUENCE {
+//             version                 INTEGER (1 ..  127),
+//             name                    LDAPDN,
+//             authentication          AuthenticationChoice }
+const TagBindRequest = 0
+const BindRequestVersionMin = 1
+const BindRequestVersionMax = 127
+
+type BindRequest struct {
+	version        INTEGER
+	name           LDAPDN
+	authentication AuthenticationChoice
+}
+
+//
+//        AuthenticationChoice ::= CHOICE {
+//             simple                  [0] OCTET STRING,
+//                                     -- 1 and 2 reserved
+//             sasl                    [3] SaslCredentials,
+//             ...  }
+const TagAuthenticationChoiceSimple = 0
+const TagAuthenticationChoiceSaslCredentials = 3
+
+type AuthenticationChoice interface {
+	sizeTagged(int) int
+}
+
+//
+//        SaslCredentials ::= SEQUENCE {
+//             mechanism               LDAPString,
+//             credentials             OCTET STRING OPTIONAL }
+type SaslCredentials struct {
+	mechanism   LDAPString
+	credentials *OCTETSTRING
+}
+
+//
+//        BindResponse ::= [APPLICATION 1] SEQUENCE {
+//             COMPONENTS OF LDAPResult,
+//             serverSaslCreds    [7] OCTET STRING OPTIONAL }
+const TagBindResponse = 1
+const TagBindResponseServerSaslCreds = 7
+
+type BindResponse struct {
+	LDAPResult
+	serverSaslCreds *OCTETSTRING
+}
+
+//
+//        UnbindRequest ::= [APPLICATION 2] NULL
+const TagUnbindRequest = 2
+
+type UnbindRequest struct {
+}
+
+//
+//        SearchRequest ::= [APPLICATION 3] SEQUENCE {
+//             baseObject      LDAPDN,
+//             scope           ENUMERATED {
+//                  baseObject              (0),
+//                  singleLevel             (1),
+//                  wholeSubtree            (2),
+//                  ...  },
+//             derefAliases    ENUMERATED {
+//                  neverDerefAliases       (0),
+//                  derefInSearching        (1),
+//                  derefFindingBaseObj     (2),
+//                  derefAlways             (3) },
+//             sizeLimit       INTEGER (0 ..  maxInt),
+//             timeLimit       INTEGER (0 ..  maxInt),
+//             typesOnly       BOOLEAN,
+//             filter          Filter,
+//             attributes      AttributeSelection }
+const TagSearchRequest = 3
+
+type SearchRequest struct {
+	baseObject   LDAPDN
+	scope        ENUMERATED
+	derefAliases ENUMERATED
+	sizeLimit    INTEGER
+	timeLimit    INTEGER
+	typesOnly    BOOLEAN
+	filter       Filter
+	attributes   AttributeSelection
+}
+
+const SearchRequestScopeBaseObject = 0
+const SearchRequestSingleLevel = 1
+const SearchRequestHomeSubtree = 2
+
+var EnumeratedSearchRequestScope = map[ENUMERATED]string{
+	SearchRequestScopeBaseObject: "baseObject",
+	SearchRequestSingleLevel:     "singleLevel",
+	SearchRequestHomeSubtree:     "homeSubtree",
+}
+
+const SearchRequetDerefAliasesNeverDerefAliases = 0
+const SearchRequetDerefAliasesDerefInSearching = 1
+const SearchRequetDerefAliasesDerefFindingBaseObj = 2
+const SearchRequetDerefAliasesDerefAlways = 3
+
+var EnumeratedSearchRequestDerefAliases = map[ENUMERATED]string{
+	SearchRequetDerefAliasesNeverDerefAliases:   "neverDerefAliases",
+	SearchRequetDerefAliasesDerefInSearching:    "derefInSearching",
+	SearchRequetDerefAliasesDerefFindingBaseObj: "derefFindingBaseObj",
+	SearchRequetDerefAliasesDerefAlways:         "derefAlways",
+}
+
+//
+//        AttributeSelection ::= SEQUENCE OF selector LDAPString
+//                       -- The LDAPString is constrained to
+//                       -- <attributeSelector> in Section 4.5.1.8
+type AttributeSelection []LDAPString
+
+//
+//        Filter ::= CHOICE {
+//             and             [0] SET SIZE (1..MAX) OF filter Filter,
+//             or              [1] SET SIZE (1..MAX) OF filter Filter,
+//             not             [2] Filter,
+//             equalityMatch   [3] AttributeValueAssertion,
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 57]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//             substrings      [4] SubstringFilter,
+//             greaterOrEqual  [5] AttributeValueAssertion,
+//             lessOrEqual     [6] AttributeValueAssertion,
+//             present         [7] AttributeDescription,
+//             approxMatch     [8] AttributeValueAssertion,
+//             extensibleMatch [9] MatchingRuleAssertion,
+//             ...  }
+const TagFilterAnd = 0
+const TagFilterOr = 1
+const TagFilterNot = 2
+const TagFilterEqualityMatch = 3
+const TagFilterSubstrings = 4
+const TagFilterGreaterOrEqual = 5
+const TagFilterLessOrEqual = 6
+const TagFilterPresent = 7
+const TagFilterApproxMatch = 8
+const TagFilterExtensibleMatch = 9
+
+type Filter interface {
+	size() int
+	write(*Bytes) int
+	getFilterTag() int
+}
+type FilterAnd []Filter
+type FilterOr []Filter
+type FilterNot struct {
+	Filter
+}
+type FilterEqualityMatch AttributeValueAssertion
+type FilterSubstrings SubstringFilter
+type FilterGreaterOrEqual AttributeValueAssertion
+type FilterLessOrEqual AttributeValueAssertion
+type FilterPresent AttributeDescription
+type FilterApproxMatch AttributeValueAssertion
+type FilterExtensibleMatch MatchingRuleAssertion
+
+//
+//        SubstringFilter ::= SEQUENCE {
+//             type           AttributeDescription,
+//             substrings     SEQUENCE SIZE (1..MAX) OF substring CHOICE {
+//                  initial [0] AssertionValue,  -- can occur at most once
+//                  any     [1] AssertionValue,
+//                  final   [2] AssertionValue } -- can occur at most once
+//             }
+type SubstringFilter struct {
+	type_      AttributeDescription
+	substrings []Substring
+}
+
+type Substring interface{}
+
+const TagSubstringInitial = 0
+const TagSubstringAny = 1
+const TagSubstringFinal = 2
+
+type SubstringInitial AssertionValue
+type SubstringAny AssertionValue
+type SubstringFinal AssertionValue
+
+//
+//        MatchingRuleAssertion ::= SEQUENCE {
+//             matchingRule    [1] MatchingRuleId OPTIONAL,
+//             type            [2] AttributeDescription OPTIONAL,
+//             matchValue      [3] AssertionValue,
+//             dnAttributes    [4] BOOLEAN DEFAULT FALSE }
+type MatchingRuleAssertion struct {
+	matchingRule *MatchingRuleId
+	type_        *AttributeDescription
+	matchValue   AssertionValue
+	dnAttributes BOOLEAN
+}
+
+const TagMatchingRuleAssertionMatchingRule = 1
+const TagMatchingRuleAssertionType = 2
+const TagMatchingRuleAssertionMatchValue = 3
+const TagMatchingRuleAssertionDnAttributes = 4
+
+//
+//        SearchResultEntry ::= [APPLICATION 4] SEQUENCE {
+//             objectName      LDAPDN,
+//             attributes      PartialAttributeList }
+const TagSearchResultEntry = 4
+
+type SearchResultEntry struct {
+	objectName LDAPDN
+	attributes PartialAttributeList
+}
+
+//
+//        PartialAttributeList ::= SEQUENCE OF
+//                             partialAttribute PartialAttribute
+type PartialAttributeList []PartialAttribute
+
+//
+//        SearchResultReference ::= [APPLICATION 19] SEQUENCE
+//                                  SIZE (1..MAX) OF uri URI
+const TagSearchResultReference = 19
+
+type SearchResultReference []URI
+
+//
+//        SearchResultDone ::= [APPLICATION 5] LDAPResult
+const TagSearchResultDone = 5
+
+type SearchResultDone LDAPResult
+
+//
+//        ModifyRequest ::= [APPLICATION 6] SEQUENCE {
+//             object          LDAPDN,
+//             changes         SEQUENCE OF change SEQUENCE {
+//                  operation       ENUMERATED {
+//                       add     (0),
+//                       delete  (1),
+//                       replace (2),
+//                       ...  },
+//                  modification    PartialAttribute } }
+const TagModifyRequest = 6
+
+type ModifyRequest struct {
+	object  LDAPDN
+	changes []ModifyRequestChange
+}
+type ModifyRequestChange struct {
+	operation    ENUMERATED
+	modification PartialAttribute
+}
+
+const ModifyRequestChangeOperationAdd = 0
+const ModifyRequestChangeOperationDelete = 1
+const ModifyRequestChangeOperationReplace = 2
+
+var EnumeratedModifyRequestChangeOperation = map[ENUMERATED]string{
+	ModifyRequestChangeOperationAdd:     "add",
+	ModifyRequestChangeOperationDelete:  "delete",
+	ModifyRequestChangeOperationReplace: "replace",
+}
+
+//
+//        ModifyResponse ::= [APPLICATION 7] LDAPResult
+const TagModifyResponse = 7
+
+type ModifyResponse LDAPResult
+
+//
+//
+//
+//
+//
+//
+//Sermersheim                 Standards Track                    [Page 58]
+//
+//
+//RFC 4511                         LDAPv3                        June 2006
+//
+//
+//        AddRequest ::= [APPLICATION 8] SEQUENCE {
+//             entry           LDAPDN,
+//             attributes      AttributeList }
+const TagAddRequest = 8
+
+type AddRequest struct {
+	entry      LDAPDN
+	attributes AttributeList
+}
+
+//
+//        AttributeList ::= SEQUENCE OF attribute Attribute
+type AttributeList []Attribute
+
+//
+//        AddResponse ::= [APPLICATION 9] LDAPResult
+const TagAddResponse = 9
+
+type AddResponse LDAPResult
+
+//
+//        DelRequest ::= [APPLICATION 10] LDAPDN
+const TagDelRequest = 10
+
+type DelRequest LDAPDN
+
+//
+//        DelResponse ::= [APPLICATION 11] LDAPResult
+const TagDelResponse = 11
+
+type DelResponse LDAPResult
+
+//
+//        ModifyDNRequest ::= [APPLICATION 12] SEQUENCE {
+//             entry           LDAPDN,
+//             newrdn          RelativeLDAPDN,
+//             deleteoldrdn    BOOLEAN,
+//             newSuperior     [0] LDAPDN OPTIONAL }
+const TagModifyDNRequest = 12
+
+type ModifyDNRequest struct {
+	entry        LDAPDN
+	newrdn       RelativeLDAPDN
+	deleteoldrdn BOOLEAN
+	newSuperior  *LDAPDN
+}
+
+const TagModifyDNRequestNewSuperior = 0
+
+//
+//        ModifyDNResponse ::= [APPLICATION 13] LDAPResult
+const TagModifyDNResponse = 13
+
+type ModifyDNResponse LDAPResult
+
+//
+//        CompareRequest ::= [APPLICATION 14] SEQUENCE {
+//             entry           LDAPDN,
+//             ava             AttributeValueAssertion }
+const TagCompareRequest = 14
+
+type CompareRequest struct {
+	entry LDAPDN
+	ava   AttributeValueAssertion
+}
+
+//        CompareResponse ::= [APPLICATION 15] LDAPResult
+const TagCompareResponse = 15
+
+type CompareResponse LDAPResult
+
+//
+//        AbandonRequest ::= [APPLICATION 16] MessageID
+const TagAbandonRequest = 16
+
+type AbandonRequest MessageID
+
+//
+//        ExtendedRequest ::= [APPLICATION 23] SEQUENCE {
+//             requestName      [0] LDAPOID,
+//             requestValue     [1] OCTET STRING OPTIONAL }
+const TagExtendedRequest = 23
+
+type ExtendedRequest struct {
+	requestName  LDAPOID
+	requestValue *OCTETSTRING
+}
+
+const TagExtendedRequestName = 0
+const TagExtendedRequestValue = 1
+
+//
+//        ExtendedResponse ::= [APPLICATION 24] SEQUENCE {
+//             COMPONENTS OF LDAPResult,
+//             responseName     [10] LDAPOID OPTIONAL,
+//             responseValue    [11] OCTET STRING OPTIONAL }
+const TagExtendedResponse = 24
+
+type ExtendedResponse struct {
+	LDAPResult
+	responseName  *LDAPOID
+	responseValue *OCTETSTRING
+}
+
+const TagExtendedResponseName = 10
+const TagExtendedResponseValue = 11
+
+//
+//        IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
+//             responseName     [0] LDAPOID OPTIONAL,
+//             responseValue    [1] OCTET STRING OPTIONAL }
+const TagIntermediateResponse = 25
+
+type IntermediateResponse struct {
+	responseName  *LDAPOID
+	responseValue *OCTETSTRING
+}
+
+const TagIntermediateResponseName = 0
+const TagIntermediateResponseValue = 1
+
+//
+//        END
+//
--- a/goldap/struct_methods.go
+++ b/goldap/struct_methods.go
@ -0,0 +1,7 @@
+package message
+
+func NewLDAPMessageWithProtocolOp(po ProtocolOp) *LDAPMessage {
+	m := NewLDAPMessage()
+	m.protocolOp = po
+	return m
+}
--- a/goldap/unbind_request.go
+++ b/goldap/unbind_request.go
@ -0,0 +1,38 @@
+package message
+
+import "fmt"
+
+//
+//        UnbindRequest ::= [APPLICATION 2] NULL
+func readUnbindRequest(bytes *Bytes) (unbindrequest UnbindRequest, err error) {
+	var tagAndLength TagAndLength
+	tagAndLength, err = bytes.ParseTagAndLength()
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readUnbindRequest:\n%s", err.Error())}
+		return
+	}
+	err = tagAndLength.Expect(classApplication, TagUnbindRequest, isNotCompound)
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readUnbindRequest:\n%s", err.Error())}
+		return
+	}
+	if tagAndLength.Length != 0 {
+		err = LdapError{"readUnbindRequest: expecting NULL"}
+		return
+	}
+	return
+}
+
+//
+//        UnbindRequest ::= [APPLICATION 2] NULL
+func (u UnbindRequest) write(bytes *Bytes) (size int) {
+	size += bytes.WriteTagAndLength(classApplication, isNotCompound, TagUnbindRequest, 0)
+	return
+}
+
+//
+//        UnbindRequest ::= [APPLICATION 2] NULL
+func (u UnbindRequest) size() (size int) {
+	size = sizeTagAndLength(TagUnbindRequest, 0)
+	return
+}
--- a/goldap/uri.go
+++ b/goldap/uri.go
@ -0,0 +1,32 @@
+package message
+
+import "fmt"
+
+//
+//        URI ::= LDAPString     -- limited to characters permitted in
+//                               -- URIs
+func readURI(bytes *Bytes) (uri URI, err error) {
+	var ldapstring LDAPString
+	ldapstring, err = readLDAPString(bytes)
+	// @TODO: check permitted chars in URI
+	if err != nil {
+		err = LdapError{fmt.Sprintf("readURI:\n%s", err.Error())}
+		return
+	}
+	uri = URI(ldapstring)
+	return
+}
+
+//
+//        URI ::= LDAPString     -- limited to characters permitted in
+//                               -- URIs
+func (u URI) write(bytes *Bytes) int {
+	return LDAPString(u).write(bytes)
+}
+
+//
+//        URI ::= LDAPString     -- limited to characters permitted in
+//                               -- URIs
+func (u URI) size() int {
+	return LDAPString(u).size()
+}
--- a/goldap/write.go
+++ b/goldap/write.go
@ -0,0 +1,6 @@
+package message
+
+type Writable interface {
+	write(bytes *Bytes) int
+	writeTagged(bytes *Bytes, class int, tag int) int
+}
--- a/goldap/write_test.go
+++ b/goldap/write_test.go
@ -0,0 +1,19 @@
+package message
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestWriteLDAPMessage(t *testing.T) {
+
+	var testData = getLDAPMessageTestData()
+	for i, test := range testData {
+		bytes, err := test.out.Write()
+		if err != nil {
+			t.Errorf("#%d error at offset %d (%s): %s\nEXPECTED BYTES: %#v\nWRITTEN BYTES: %#v\n", i, test.bytes.offset, test.bytes.DumpCurrentBytes(), err, test.bytes.getBytes(), bytes.getBytes())
+		} else if !reflect.DeepEqual(bytes.getBytes(), test.bytes.getBytes()) {
+			t.Errorf("#%d:\nGOT:\n%#+v\nEXPECTED:\n%#+v", i, bytes.getBytes(), test.bytes.getBytes())
+		}
+	}
+}
--- a/gomod2nix.toml
+++ b/gomod2nix.toml
@ -0,0 +1,153 @@
+schema = 3
+
+[mod]
+  [mod."github.com/armon/circbuf"]
+    version = "v0.0.0-20150827004946-bbbad097214e"
+    hash = "sha256-klQjllsJZqZ2KPNx1mZT9XP+UAJkuBhmTnZdNlAflEM="
+  [mod."github.com/armon/go-metrics"]
+    version = "v0.0.0-20180917152333-f0300d1749da"
+    hash = "sha256-+zqX1hlJgc+IrXRzBQDMhR8GYQdc0Oj6PiIDfctgh44="
+  [mod."github.com/armon/go-radix"]
+    version = "v0.0.0-20180808171621-7fddfc383310"
+    hash = "sha256-ZHU4pyBqHHRuQJuYr2K+LqeAnLX9peX07cmSYK+GDHk="
+  [mod."github.com/bgentry/speakeasy"]
+    version = "v0.1.0"
+    hash = "sha256-Gt1vj6CFovLnO6wX5u2O4UfecY9V2J9WGw1ez4HMrgk="
+  [mod."github.com/davecgh/go-spew"]
+    version = "v1.1.1"
+    hash = "sha256-nhzSUrE1fCkN0+RL04N4h8jWmRFPPPWbCuDc7Ss0akI="
+  [mod."github.com/fatih/color"]
+    version = "v1.7.0"
+    hash = "sha256-4In7ef7it7d+6oGUJ3pkD0V+lsL40hVtYdy2KD2ovn0="
+  [mod."github.com/google/btree"]
+    version = "v0.0.0-20180813153112-4030bb1f1f0c"
+    hash = "sha256-5gr0RMnlvrzCke3kwpkf92WvW3x5nnKZesoulyoYRC0="
+  [mod."github.com/google/uuid"]
+    version = "v1.1.1"
+    hash = "sha256-66PXC/RCPUyhS9PhkIPQFR3tbM2zZYDNPGXN7JJj3UE="
+  [mod."github.com/hashicorp/consul/api"]
+    version = "v1.3.0"
+    hash = "sha256-fMORNFAWK2GkRbBl/KzNHrvtCfwz/7P66HzDaE4GnuE="
+  [mod."github.com/hashicorp/consul/sdk"]
+    version = "v0.3.0"
+    hash = "sha256-lF47JPGfmeGjpuQw9VSNs2Mi+G7FQLKrrHteX3iXfpU="
+  [mod."github.com/hashicorp/errwrap"]
+    version = "v1.0.0"
+    hash = "sha256-LGSLrefkABG1kH1i+GUWiD2/ggJxiZEJ+D2YNbhZjmo="
+  [mod."github.com/hashicorp/go-cleanhttp"]
+    version = "v0.5.1"
+    hash = "sha256-c54zcHr9THj3MQk7hrDQcpjOcQi1MvXZ4Kpin6EbfR4="
+  [mod."github.com/hashicorp/go-immutable-radix"]
+    version = "v1.0.0"
+    hash = "sha256-JmNxdGaJG63Ty/sVnPjqvTyA4/k5wkzZ/QvpMK2uduw="
+  [mod."github.com/hashicorp/go-msgpack"]
+    version = "v0.5.3"
+    hash = "sha256-2OUYjD/Jt12TFBrtH0wRqg+lzRljDxSIhk2CqBLUczo="
+  [mod."github.com/hashicorp/go-multierror"]
+    version = "v1.0.0"
+    hash = "sha256-iXzjerl96o7QDiSwQjbak8R/t+YzZeoUqm59TCmy3gI="
+  [mod."github.com/hashicorp/go-rootcerts"]
+    version = "v1.0.0"
+    hash = "sha256-4NZJAT5/vocyto+dv6FmW4kFiYldmNvewowsYK/LiTI="
+  [mod."github.com/hashicorp/go-sockaddr"]
+    version = "v1.0.0"
+    hash = "sha256-orG+SHVsp5lgNRCErmhMLABVFQ3ZWfYIJ/4LTFzlvao="
+  [mod."github.com/hashicorp/go-syslog"]
+    version = "v1.0.0"
+    hash = "sha256-YRuq6oPMwAFVY7mvwpMDvZqGwNnb5CjBYyKI/x5mbCc="
+  [mod."github.com/hashicorp/go-uuid"]
+    version = "v1.0.1"
+    hash = "sha256-s1wIvBu37z4U3qK9sdUR1CtbD39N6RwfX4HgDCpCa0s="
+  [mod."github.com/hashicorp/go.net"]
+    version = "v0.0.1"
+    hash = "sha256-JKal3E+wPO+Hk838opKV4HHKB4O72Xy+77ncXlLkWRk="
+  [mod."github.com/hashicorp/golang-lru"]
+    version = "v0.5.0"
+    hash = "sha256-Lo0UyOZQ89iK0Ui3Hfk5VkWqxEzLw6Lclq4EM8VlYoo="
+  [mod."github.com/hashicorp/logutils"]
+    version = "v1.0.0"
+    hash = "sha256-e8t8Dm8sp/PzKClN1TOmFcrTAWNh4mZHSW7cAjVx3Bw="
+  [mod."github.com/hashicorp/mdns"]
+    version = "v1.0.0"
+    hash = "sha256-ravx4tklQG43OEjPiJn68iJM9ODZ6hgU0idFCEOiJGM="
+  [mod."github.com/hashicorp/memberlist"]
+    version = "v0.1.3"
+    hash = "sha256-IsxqevYulPt+2VGtlq068Jyq1YfIk4Ohh9TgakIGxnc="
+  [mod."github.com/hashicorp/serf"]
+    version = "v0.8.2"
+    hash = "sha256-diRxWOouFLTO75f2E9NlrKgie/qsT+gOOrrbf4tACHw="
+  [mod."github.com/jsimonetti/pwscheme"]
+    version = "v0.0.0-20220125093853-4d9895f5db73"
+    hash = "sha256-YF3RKU/4CWvLPgGzUd7Hk/2+41OUFuRWZgzQuqcsKg0="
+  [mod."github.com/konsorten/go-windows-terminal-sequences"]
+    version = "v1.0.1"
+    hash = "sha256-Nwp+Cza9dIu3ogVGip6wyOjWwwaq+2hU3eYIe4R7kNE="
+  [mod."github.com/mattn/go-colorable"]
+    version = "v0.0.9"
+    hash = "sha256-fVPF8VxbdggLAZnaexMl6Id1WjXKImzVySxKfa+ukts="
+  [mod."github.com/mattn/go-isatty"]
+    version = "v0.0.3"
+    hash = "sha256-9ogEEd8/kl/dImldzdBmTFdepvB0dVXEzN4o8bEqhBs="
+  [mod."github.com/miekg/dns"]
+    version = "v1.0.14"
+    hash = "sha256-OeijUgBaEmDapclTxfvjIqrjh4qZu3+DQpHelGGI4aA="
+  [mod."github.com/mitchellh/cli"]
+    version = "v1.0.0"
+    hash = "sha256-4nG7AhRcjTRCwUCdnaNaFrAKDxEEoiihaCA4lk+uM8U="
+  [mod."github.com/mitchellh/go-homedir"]
+    version = "v1.0.0"
+    hash = "sha256-eGmBNNTuDSMwicjTNgB54IEJuK1tgOLDJ3NHTpQCHzg="
+  [mod."github.com/mitchellh/go-testing-interface"]
+    version = "v1.0.0"
+    hash = "sha256-/Dpv/4i5xuK8hDH+q8YTdF6Jg6NNtfO4Wqig2JCWgrY="
+  [mod."github.com/mitchellh/gox"]
+    version = "v0.4.0"
+    hash = "sha256-GV3LYxzJt8YVbnSac2orlj2QR3MX/YIDrLkSkPhsjuA="
+  [mod."github.com/mitchellh/iochan"]
+    version = "v1.0.0"
+    hash = "sha256-b5Tp7cw/e8mL++IjsebbmKWXtb9Hrzu4Fc6M4tZKFhU="
+  [mod."github.com/mitchellh/mapstructure"]
+    version = "v1.1.2"
+    hash = "sha256-OU9HZYHtl0qaqMFd84w7snkkRuRY6UMSsfCnL5HYdw0="
+  [mod."github.com/pascaldekloe/goe"]
+    version = "v0.0.0-20180627143212-57f6aae5913c"
+    hash = "sha256-2KUjqrEC/BwkTZRxImazcI/C3H7QmXfNrlt8slwdDbc="
+  [mod."github.com/pkg/errors"]
+    version = "v0.8.1"
+    hash = "sha256-oe3iddfoLRwpC3ki5fifHf2ZFprtg99iNak50shiuDw="
+  [mod."github.com/pmezard/go-difflib"]
+    version = "v1.0.0"
+    hash = "sha256-/FtmHnaGjdvEIKAJtrUfEhV7EVo5A/eYrtdnUkuxLDA="
+  [mod."github.com/posener/complete"]
+    version = "v1.1.1"
+    hash = "sha256-heyPMSBzVlx7ZKgTyzl/xmUfZw3EZCcvGFGrRMIbIr8="
+  [mod."github.com/ryanuber/columnize"]
+    version = "v0.0.0-20160712163229-9b3edd62028f"
+    hash = "sha256-RLUQcU6Z03upKe08v6rjn9/tkyrQsgmpdEmBtWaLQfk="
+  [mod."github.com/sean-/seed"]
+    version = "v0.0.0-20170313163322-e2103e2c3529"
+    hash = "sha256-RQQTjvf8Y91jP5FGOyEnGMFw7zCrcSnUU4eH2CXKkT4="
+  [mod."github.com/sirupsen/logrus"]
+    version = "v1.4.2"
+    hash = "sha256-3QzWUsapCmg3F7JqUuINT3/UG097uzLff6iCcCgQ43o="
+  [mod."github.com/stretchr/objx"]
+    version = "v0.1.1"
+    hash = "sha256-HdGVZCuy7VprC5W9UxGbDmXqsKADMjpEDht7ilGVLco="
+  [mod."github.com/stretchr/testify"]
+    version = "v1.3.0"
+    hash = "sha256-+mSebBNccNcxbY462iKTNTWmd5ZuUkUqFebccn3EtIA="
+  [mod."golang.org/x/crypto"]
+    version = "v0.0.0-20200604202706-70a84ac30bf9"
+    hash = "sha256-I5ov2lV6ubB3H3pn6DFN1VPLyxeLfPUaOx2PJ9K1KH8="
+  [mod."golang.org/x/net"]
+    version = "v0.0.0-20190404232315-eb5bcb51f2a3"
+    hash = "sha256-kwP+BDfPsZEeeceyg4H5LgdTDT8O8YWbkpCkpyuPJJo="
+  [mod."golang.org/x/sync"]
+    version = "v0.0.0-20181221193216-37e7f081c4d4"
+    hash = "sha256-FUpv9bmGLDEjCxXdvR0CRDqOKRY0xrHRPzOsyQyvYK0="
+  [mod."golang.org/x/sys"]
+    version = "v0.0.0-20190422165155-953cdadca894"
+    hash = "sha256-YkQjSZaiVFxrmXYSKmqrGeIO3RZ95fc3dWyCaR+SosY="
+  [mod."golang.org/x/text"]
+    version = "v0.3.0"
+    hash = "sha256-0FFbaxF1ZuAQF3sCcA85e8MO6prFeHint36inija4NY="
--- a/ldapserver/client.go
+++ b/ldapserver/client.go
@ -6,7 +6,7 @@ import (
 	"sync"
 	"time"

-	ldap "github.com/lor00x/goldap/message"
+	ldap "bottin/goldap"
 )

 type UserState interface{}
@ -206,7 +206,10 @@ func (c *client) close() {
 }

 func (c *client) writeMessage(m *ldap.LDAPMessage) {
-	data, _ := m.Write()
+	data, err := m.Write()
+	if err != nil {
+		Logger.Errorf("bottin: unable to marshal response message: %v", err)
+	}

 	//Logger.Printf(">>> %d - %s - hex=%x", c.Numero, m.ProtocolOpName(), data.Bytes())
 	Logger.Tracef(">>> [%d] %#v", c.Numero, m)
--- a/ldapserver/constants.go
+++ b/ldapserver/constants.go
@ -1,6 +1,6 @@
 package ldapserver

-import ldap "github.com/lor00x/goldap/message"
+import ldap "bottin/goldap"

 // LDAP Application Codes
 const (
--- a/ldapserver/message.go
+++ b/ldapserver/message.go
@ -3,7 +3,7 @@ package ldapserver
 import (
 	"fmt"

-	ldap "github.com/lor00x/goldap/message"
+	ldap "bottin/goldap"
 )

 type Message struct {
--- a/ldapserver/packet.go
+++ b/ldapserver/packet.go
@ -5,7 +5,7 @@ import (
 	"errors"
 	"fmt"

-	ldap "github.com/lor00x/goldap/message"
+	ldap "bottin/goldap"
 )

 type messagePacket struct {
--- a/ldapserver/responsemessage.go
+++ b/ldapserver/responsemessage.go
@ -1,6 +1,6 @@
 package ldapserver

-import ldap "github.com/lor00x/goldap/message"
+import ldap "bottin/goldap"

 func NewBindResponse(resultCode int) ldap.BindResponse {
 	r := ldap.BindResponse{}
--- a/ldapserver/route.go
+++ b/ldapserver/route.go
@ -3,7 +3,7 @@ package ldapserver
 import (
 	"strings"

-	ldap "github.com/lor00x/goldap/message"
+	ldap "bottin/goldap"
 )

 // Constant to LDAP Request protocol Type names
--- a/main.go
+++ b/main.go
@ -12,10 +12,10 @@ import (
 	"os/signal"
 	"syscall"

+	message "bottin/goldap"
 	ldap "bottin/ldapserver"

 	consul "github.com/hashicorp/consul/api"
-	message "github.com/lor00x/goldap/message"
 	log "github.com/sirupsen/logrus"
 )

@ -320,7 +320,6 @@ func (server *Server) init() error {
 		return err
 	}

-
 	admin_pass_str, environnement_variable_exist := os.LookupEnv("BOTTIN_DEFAULT_ADMIN_PW")
 	if !environnement_variable_exist {
 		admin_pass := make([]byte, 8)
@ -333,7 +332,11 @@ func (server *Server) init() error {
 		server.logger.Debug("BOTTIN_DEFAULT_ADMIN_PW environment variable is set, using it for admin's password")
 	}

-	admin_pass_hash := SSHAEncode([]byte(admin_pass_str))
+	admin_pass_hash, err := SSHAEncode(admin_pass_str)
+	if err != nil {
+		server.logger.Error("can't create admin password")
+		panic(err)
+	}

 	admin_dn := "cn=admin," + server.config.Suffix
 	admin_attributes := Entry{
@ -434,8 +437,8 @@ func (server *Server) handleBindInternal(state *State, r *message.BindRequest) (
 	}

 	for _, hash := range passwd {
-		valid := SSHAMatches(hash, []byte(r.AuthenticationSimple()))
-		if valid {
+		valid, err := SSHAMatches(hash, string(r.AuthenticationSimple()))
+		if valid && err == nil {
 			groups, err := server.getAttribute(string(r.Name()), ATTR_MEMBEROF)
 			if err != nil {
 				return ldap.LDAPResultOperationsError, err
@ -444,8 +447,32 @@ func (server *Server) handleBindInternal(state *State, r *message.BindRequest) (
 				user:   string(r.Name()),
 				groups: groups,
 			}
+
+			updatePasswordHash(string(r.AuthenticationSimple()), hash, server, string(r.Name()))
+
 			return ldap.LDAPResultSuccess, nil
+		} else {
+			return ldap.LDAPResultInvalidCredentials, fmt.Errorf("can't authenticate: %w", err)
 		}
 	}
 	return ldap.LDAPResultInvalidCredentials, fmt.Errorf("No password match")
 }
+
+// Update the hash if it's not already SSHA512
+func updatePasswordHash(password string, currentHash string, server *Server, dn string) {
+	hashType, err := determineHashType(currentHash)
+	if err != nil {
+		server.logger.Errorf("can't determine hash type of password")
+		return
+	}
+	if hashType != SSHA512 {
+		reencodedPassword, err := SSHAEncode(password)
+		if err != nil {
+			server.logger.Errorf("can't encode password")
+			return
+		}
+		server.putAttributes(dn, Entry{
+			ATTR_USERPASSWORD: []string{reencodedPassword},
+		})
+	}
+}
--- a/read.go
+++ b/read.go
@ -6,7 +6,7 @@ import (

 	ldap "bottin/ldapserver"

-	message "github.com/lor00x/goldap/message"
+	message "bottin/goldap"
 )

 // Generic read utility functions ----------
@ -213,10 +213,11 @@ func (server *Server) handleSearchInternal(state *State, w ldap.ResponseWriter,
 				continue
 			}
 			// Send result
+			resultVals := []message.AttributeValue{}
 			for _, v := range val {
-				e.AddAttribute(message.AttributeDescription(attr),
-					message.AttributeValue(v))
+				resultVals = append(resultVals, message.AttributeValue(v))
 			}
+			e.AddAttribute(message.AttributeDescription(attr), resultVals...)
 		}
 		w.Write(e)
 	}
--- a/ssha.go
+++ b/ssha.go
@ -1,25 +1,79 @@
 package main

 import (
+	"errors"
+	"strings"
+
 	"bytes"
 	"crypto/rand"
 	"crypto/sha1"
 	"encoding/base64"
 	"fmt"
-	"strings"
-
 	log "github.com/sirupsen/logrus"
+
+	//"github.com/jsimonetti/pwscheme/ssha"
+	"github.com/jsimonetti/pwscheme/ssha256"
+	"github.com/jsimonetti/pwscheme/ssha512"
 )

+const (
+	SSHA    = "{SSHA}"
+	SSHA256 = "{SSHA256}"
+	SSHA512 = "{SSHA512}"
+)
+
+// Encode encodes the string to ssha512
+func SSHAEncode(rawPassPhrase string) (string, error) {
+	return ssha512.Generate(rawPassPhrase, 16)
+}
+
+// Matches matches the encoded password and the raw password
+func SSHAMatches(encodedPassPhrase string, rawPassPhrase string) (bool, error) {
+	hashType, err := determineHashType(encodedPassPhrase)
+	if err != nil {
+		return false, errors.New("invalid password hash stored")
+	}
+
+	var is_ok bool
+	switch hashType {
+	case SSHA:
+		is_ok = LegacySSHAMatches(encodedPassPhrase, []byte(rawPassPhrase))
+		return is_ok, nil
+		//return ssha.Validate(rawPassPhrase, encodedPassPhrase)
+	case SSHA256:
+		return ssha256.Validate(rawPassPhrase, encodedPassPhrase)
+	case SSHA512:
+		return ssha512.Validate(rawPassPhrase, encodedPassPhrase)
+	}
+
+	return false, errors.New("no matching hash type found")
+}
+
+func determineHashType(hash string) (string, error) {
+	if len(hash) >= 7 && strings.ToUpper(string(hash[0:6])) == SSHA {
+		return SSHA, nil
+	}
+	if len(hash) >= 10 && strings.ToUpper(string(hash[0:9])) == SSHA256 {
+		return SSHA256, nil
+	}
+	if len(hash) >= 10 && strings.ToUpper(string(hash[0:9])) == SSHA512 {
+		return SSHA512, nil
+	}
+
+	return "", errors.New("no valid hash found")
+}
+
+// --- legacy
+
 // Encode encodes the []byte of raw password
-func SSHAEncode(rawPassPhrase []byte) string {
-	hash := makeSSHAHash(rawPassPhrase, makeSalt())
+func LegacySSHAEncode(rawPassPhrase []byte) string {
+	hash := legacyMakeSSHAHash(rawPassPhrase, legacyMakeSalt())
 	b64 := base64.StdEncoding.EncodeToString(hash)
 	return fmt.Sprintf("{ssha}%s", b64)
 }

 // Matches matches the encoded password and the raw password
-func SSHAMatches(encodedPassPhrase string, rawPassPhrase []byte) bool {
+func LegacySSHAMatches(encodedPassPhrase string, rawPassPhrase []byte) bool {
 	if !strings.EqualFold(encodedPassPhrase[:6], "{ssha}") {
 		return false
 	}
@ -30,7 +84,7 @@ func SSHAMatches(encodedPassPhrase string, rawPassPhrase []byte) bool {
 	}
 	salt := bhash[20:]

-	newssha := makeSSHAHash(rawPassPhrase, salt)
+	newssha := legacyMakeSSHAHash(rawPassPhrase, salt)

 	if bytes.Compare(newssha, bhash) != 0 {
 		return false
@ -39,7 +93,7 @@ func SSHAMatches(encodedPassPhrase string, rawPassPhrase []byte) bool {
 }

 // makeSalt make a 32 byte array containing random bytes.
-func makeSalt() []byte {
+func legacyMakeSalt() []byte {
 	sbytes := make([]byte, 32)
 	_, err := rand.Read(sbytes)
 	if err != nil {
@ -49,7 +103,7 @@ func makeSalt() []byte {
 }

 // makeSSHAHash make hasing using SHA-1 with salt. This is not the final output though. You need to append {SSHA} string with base64 of this hash.
-func makeSSHAHash(passphrase, salt []byte) []byte {
+func legacyMakeSSHAHash(passphrase, salt []byte) []byte {
 	sha := sha1.New()
 	sha.Write(passphrase)
 	sha.Write(salt)
--- a/test/bottin_test.go
+++ b/test/bottin_test.go
@ -147,14 +147,12 @@ func TestDeleteGroupsAfterAddedUsers(t *testing.T) {

 //Example of paralellism Test
 func TestPrincipal(t *testing.T) {
-
-	t.Run("A=1", TestAddThenDelete)
-	t.Run("A=2", TestModifyRequest)
+	t.Run("A=Add and delete", TestAddThenDelete)
+	t.Run("A=Modify", TestModifyRequest)
 	if !testing.Short() {
-		t.Run("B=1", TestConfirmAddAttributes)
-		t.Run("B=2", TestModifyRequestAndCheck)
-		t.Run("C=1", TestAddUserInGroup)
-		t.Run("C=2", TestDeleteGroupsAfterAddedUsers)
+		t.Run("B=Add attributes", TestConfirmAddAttributes)
+		t.Run("B=Modify and check", TestModifyRequestAndCheck)
+		t.Run("C=Add user in group", TestAddUserInGroup)
+		t.Run("C=Delete group", TestDeleteGroupsAfterAddedUsers)
 	}
-
 }
--- a/test/handler.go
+++ b/test/handler.go
@ -54,18 +54,6 @@ func (inst *instance) GenerateName() (name string) {
 	return
 }

-//Handler to around the bug with MessageId
-func (inst *instance) Reconnect() (err error) {
-	inst.logging.Close()
-	inst.logging, err = ldap.Dial("tcp", fmt.Sprintf("%s:%d", adresse, port))
-	if err != nil {
-		return
-	}
-	err = inst.logging.Bind(bindusername, bindpassword)
-	//logging.Debug("Reconnect succesful")
-	return
-}
-
 //Transform attributes in map format to the struct attributes
 func MapAttToStruct(att map[string][]string) []attributes {
 	resultat := []attributes{}
@ -88,7 +76,7 @@ func Connect() (*ldap.Conn, error) {
 	if key, ok := os.LookupEnv("BOTTIN_DEFAULT_ADMIN_PW"); ok {
 		bindpassword = key
 	}
-
+	//l.Debug.Enable(true)
 	err = l.Bind(bindusername, bindpassword)
 	logging.Debug("Connection succesful")
 	return l, err
--- a/test/request.go
+++ b/test/request.go
@ -13,8 +13,6 @@ func (inst *instance) Add_Request(dn string, attributes map[string][]string) err

 	//Send the request
 	err := inst.logging.Add(req)
-	//@FIXME: Remove when you try to correct the bug MessageID
-	inst.Reconnect()
 	return err

 }
@ -36,8 +34,6 @@ func (inst *instance) Modify_Request(dn string, add_attributes, delete_attribute
 	}

 	err := inst.logging.Modify(modifyReq)
-	//@FIXME: Remove when you try to correct the bug MessageID
-	inst.Reconnect()
 	return err
 }

@ -45,8 +41,6 @@ func (inst *instance) Delete_Request(dn string) error {
 	del := ldap.NewDelRequest(dn, nil)

 	err := inst.logging.Del(del)
-	//@FIXME: Remove when you try to correct the bug MessageID
-	inst.Reconnect()
 	return err
 }

@ -61,7 +55,5 @@ func (inst *instance) Search_Request(dn, filter string, name_attributes []string

 	res, err := inst.logging.Search(searchReq)
 	logging.Debugf("Search Request made with: dn: %s, filter: %s, attributes: %s. \n", dn, filter, name_attributes)
-	//@FIXME: Remove when you try to correct the bug MessageID
-	inst.Reconnect()
 	return res, err
 }
--- a/test/runner.sh
+++ b/test/runner.sh
@ -6,7 +6,11 @@ echo $BOTTIN_DEFAULT_ADMIN_PW
 consul agent -dev > /dev/null 2>&1 &
 sleep 2
 cp test/config.json.test config.json
-./bottin > /dev/null 2>&1 &
+./bottin > /tmp/bottin.log 2>&1 &
 sleep 1
 ./test/test -test.v -test.failfast -test.short -test.run TestPrincipal
 ./test/test -test.v -test.failfast -test.run TestPrincipal/B=
+
+jobs
+kill %2
+kill %1
--- a/write.go
+++ b/write.go
@ -7,8 +7,9 @@ import (

 	ldap "bottin/ldapserver"

+	message "bottin/goldap"
+
 	consul "github.com/hashicorp/consul/api"
-	message "github.com/lor00x/goldap/message"
 )

 // Generic item modification function --------
@ -65,6 +66,24 @@ func (server *Server) putAttributes(dn string, attrs Entry) error {
 			}
 		}

+		// if the password is not yet hashed we hash it
+		if k == ATTR_USERPASSWORD {
+			tmpValues := []string{}
+			for _, pw := range values {
+				_, err := determineHashType(pw)
+				if err != nil {
+					encodedPassword, err := SSHAEncode(pw)
+					if err != nil {
+						return err
+					}
+					tmpValues = append(tmpValues, encodedPassword)
+				} else {
+					tmpValues = append(tmpValues, pw)
+				}
+			}
+			values = tmpValues
+		}
+
 		// If we have zero values, delete associated k/v pair
 		// Otherwise, write new values
 		if len(values) == 0 {
Author	SHA1	Message	Date
Alex Auvolat	1d338a9cc1	fix consul version in ci	2024-03-20 17:02:45 +00:00
Alex Auvolat	e9bf550e02	Woodpecker CI	2024-03-20 17:02:45 +00:00
Adrien	55ef7530ae	cleaned Docker process	2023-03-27 10:23:32 +02:00
Quentin Dufour	a2be316d91	use legacy ssha algorithm, new one is incompatible	2023-03-26 09:41:22 +02:00
Alex Auvolat	9cab98d2ce	Set correct package path	2022-12-01 22:43:06 +01:00
Alex Auvolat	de71260bbf	Make repo a Nix flake	2022-12-01 22:40:13 +01:00
Quentin Dufour	0ef8313a67	Add Nix packaging	2022-07-24 09:47:31 +02:00
Simon Beck	9ce0d22c99	Fix wrong handling of multi value attributes While ldapsearch doesn't seem to mind, apps like keycloak seem to have issues with adding multiple attributes with different values. While the resulting ldif in ldapsearch is indistinguishable there seems to be a slight different on the protocol level. If adding multiple attributes with the same name and different values, keycloak will only see the last entry. But adding a single attribute a slice of values is seems to handle it correctly.	2022-02-14 12:13:31 +01:00
Simon Beck	f05e41c9aa	Improve password hash handling This adds support for more hash algorithms. Also a stored password will be updated to SSHA512 upon a successful bind. It will also automatically hash a cleartext password if the `userpassword` field is modified with a cleartext one. Hashes supported: * SSHA * SSHA256 * SSHA512	2022-02-10 20:51:01 +01:00
Quentin Dufour	dbd9003714	Disable reconnect in tests + some cosmetic changes	2021-09-16 13:52:46 +02:00
Quentin Dufour	a08be6b395	Patch ASN.1 BER encoding of integers and length + unit tests	2021-09-16 13:51:43 +02:00
Quentin Dufour	2a844bd559	Encoding errors must be logged	2021-09-16 13:47:09 +02:00
Quentin Dufour	2707dd77c5	Use vendored goldap	2021-09-16 13:46:18 +02:00
Quentin Dufour	477d7014ed	Vendor goldap	2021-09-16 13:41:01 +02:00