package main import ( "crypto/rand" "crypto/tls" "encoding/base64" "encoding/json" "flag" "fmt" "html/template" "io/ioutil" "log" "net/http" "os" "strings" "github.com/go-ldap/ldap/v3" "github.com/gorilla/sessions" ) type ConfigFile struct { HttpBindAddr string `json:"http_bind_addr"` SessionKey string `json:"session_key"` LdapServerAddr string `json:"ldap_server_addr"` LdapTLS bool `json:"ldap_tls"` UserBaseDN string `json:"user_base_dn"` UserNameAttr string `json:"user_name_attr"` GroupBaseDN string `json:"group_base_dn"` GroupNameAttr string `json:"group_name_attr"` GroupCanInvite string `json:"group_can_invite"` GroupCanAdmin string `json:"group_can_admin"` } var configFlag = flag.String("config", "./config.json", "Configuration file path") var config *ConfigFile const SESSION_NAME = "guichet_session" var store sessions.Store = nil func readConfig() ConfigFile { key_bytes := make([]byte, 32) n, err := rand.Read(key_bytes) if err != nil || n != 32 { log.Fatal(err) } config_file := ConfigFile{ HttpBindAddr: ":9991", SessionKey: base64.StdEncoding.EncodeToString(key_bytes), LdapServerAddr: "ldap://127.0.0.1:389", LdapTLS: false, UserBaseDN: "ou=users,dc=example,dc=com", UserNameAttr: "uid", GroupBaseDN: "ou=groups,dc=example,dc=com", GroupNameAttr: "gid", GroupCanInvite: "", GroupCanAdmin: "gid=admin,ou=groups,dc=example,dc=com", } _, err = os.Stat(*configFlag) if os.IsNotExist(err) { // Generate default config file log.Printf("Generating default config file as %s", *configFlag) bytes, err := json.MarshalIndent(&config_file, "", " ") if err != nil { log.Fatal(err) } err = ioutil.WriteFile(*configFlag, bytes, 0644) if err != nil { log.Fatal(err) } return config_file } if err != nil { log.Fatal(err) } bytes, err := ioutil.ReadFile(*configFlag) if err != nil { log.Fatal(err) } err = json.Unmarshal(bytes, &config_file) if err != nil { log.Fatal(err) } return config_file } func main() { flag.Parse() config_file := readConfig() config = &config_file store = sessions.NewFilesystemStore("", []byte(config.SessionKey)) http.HandleFunc("/", handleHome) http.HandleFunc("/logout", handleLogout) http.HandleFunc("/profile", handleProfile) http.HandleFunc("/passwd", handlePasswd) staticfiles := http.FileServer(http.Dir("static")) http.Handle("/static/", http.StripPrefix("/static/", staticfiles)) err := http.ListenAndServe(config.HttpBindAddr, logRequest(http.DefaultServeMux)) if err != nil { log.Fatal("Cannot start http server: ", err) } } type LoginInfo struct { Username string DN string Password string } type LoginStatus struct { Info *LoginInfo conn *ldap.Conn UserEntry *ldap.Entry } func logRequest(handler http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { log.Printf("%s %s %s\n", r.RemoteAddr, r.Method, r.URL) handler.ServeHTTP(w, r) }) } func checkLogin(w http.ResponseWriter, r *http.Request) *LoginStatus { session, err := store.Get(r, SESSION_NAME) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } username, ok := session.Values["login_username"] password, ok2 := session.Values["login_password"] user_dn, ok3 := session.Values["login_dn"] var login_info *LoginInfo if !(ok && ok2 && ok3) { login_info = handleLogin(w, r) if login_info == nil { return nil } } else { login_info = &LoginInfo{ DN: user_dn.(string), Username: username.(string), Password: password.(string), } } l := ldapOpen(w) if l == nil { return nil } err = l.Bind(login_info.DN, login_info.Password) if err != nil { delete(session.Values, "login_username") delete(session.Values, "login_password") delete(session.Values, "login_dn") err = session.Save(r, w) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } return checkLogin(w, r) } searchRequest := ldap.NewSearchRequest( login_info.DN, ldap.ScopeBaseObject, ldap.NeverDerefAliases, 0, 0, false, fmt.Sprintf("(&(objectClass=organizationalPerson))"), []string{"dn", "displayname", "givenname", "sn", "mail", "memberof"}, nil) sr, err := l.Search(searchRequest) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } if len(sr.Entries) != 1 { http.Error(w, fmt.Sprintf("Multiple entries: %#v", sr.Entries), http.StatusInternalServerError) return nil } return &LoginStatus{ Info: login_info, conn: l, UserEntry: sr.Entries[0], } } func ldapOpen(w http.ResponseWriter) *ldap.Conn { l, err := ldap.DialURL(config.LdapServerAddr) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } if config.LdapTLS { err = l.StartTLS(&tls.Config{InsecureSkipVerify: true}) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } } return l } // Page handlers ---- type HomePageData struct { Login *LoginStatus CanAdmin bool CanInvite bool } func handleHome(w http.ResponseWriter, r *http.Request) { templateHome := template.Must(template.ParseFiles("templates/layout.html", "templates/home.html")) login := checkLogin(w, r) if login == nil { return } can_admin := false can_invite := false for _, group := range login.UserEntry.GetAttributeValues("memberof") { if config.GroupCanInvite != "" && group == config.GroupCanInvite { can_invite = true } if config.GroupCanAdmin != "" && group == config.GroupCanAdmin { can_admin = true } } templateHome.Execute(w, &HomePageData{ Login: login, CanAdmin: can_admin, CanInvite: can_invite, }) } func handleLogout(w http.ResponseWriter, r *http.Request) { session, err := store.Get(r, SESSION_NAME) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return } delete(session.Values, "login_username") delete(session.Values, "login_password") delete(session.Values, "login_dn") err = session.Save(r, w) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return } http.Redirect(w, r, "/", http.StatusFound) } type LoginFormData struct { Username string ErrorMessage string } func handleLogin(w http.ResponseWriter, r *http.Request) *LoginInfo { templateLogin := template.Must(template.ParseFiles("templates/layout.html", "templates/login.html")) if r.Method == "GET" { templateLogin.Execute(w, LoginFormData{}) return nil } else if r.Method == "POST" { r.ParseForm() username := strings.Join(r.Form["username"], "") password := strings.Join(r.Form["password"], "") user_dn := fmt.Sprintf("%s=%s,%s", config.UserNameAttr, username, config.UserBaseDN) l := ldapOpen(w) if l == nil { return nil } err := l.Bind(user_dn, password) if err != nil { templateLogin.Execute(w, LoginFormData{ Username: username, ErrorMessage: err.Error(), }) return nil } // Successfully logged in, save it to session session, err := store.Get(r, SESSION_NAME) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } session.Values["login_username"] = username session.Values["login_password"] = password session.Values["login_dn"] = user_dn err = session.Save(r, w) if err != nil { http.Error(w, err.Error(), http.StatusInternalServerError) return nil } return &LoginInfo{ DN: user_dn, Username: username, Password: password, } } else { http.Error(w, "Unsupported method", http.StatusBadRequest) return nil } }