From b592754973b55d71b7c6050b82d65d8e32f161ba Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Mon, 27 May 2019 17:32:00 +0200
Subject: [PATCH 1/7] WIP refactor to capture traffic

---
 CMakeLists.txt        |  2 ++
 src/algo_dup2.c       | 10 +++---
 src/algo_naive.c      |  8 ++---
 src/algo_rr.c         | 22 ++++++-------
 src/algo_utils.c      | 73 +++++++++++++++++++++++--------------------
 src/algo_utils.h      | 61 +++++++++---------------------------
 src/capture_traffic.c |  8 +++++
 src/capture_traffic.h | 14 +++++++++
 src/donar.c           | 11 +++++--
 src/donar_client.c    |  3 +-
 src/donar_init.c      |  1 +
 src/donar_init.h      |  2 +-
 src/donar_server.c    |  3 +-
 src/proxy.c           | 57 ++++++++++++++++++---------------
 src/proxy.h           | 36 ++++++++++++++++++++-
 15 files changed, 178 insertions(+), 133 deletions(-)
 create mode 100644 src/capture_traffic.c
 create mode 100644 src/capture_traffic.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index dbba341..caeef5f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,6 +33,8 @@ list(APPEND CSOURCES
 	src/proxy.c
 	src/timer.h
 	src/timer.c
+	src/capture_traffic.h
+	src/capture_traffic.c
 )
 
 add_executable(donar ${CSOURCES} src/donar.c)
diff --git a/src/algo_dup2.c b/src/algo_dup2.c
index 530f20e..27fd1d9 100644
--- a/src/algo_dup2.c
+++ b/src/algo_dup2.c
@@ -23,7 +23,7 @@ int algo_dup2_on_stream(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
   // Check that we didn't already received the packet
   struct dup2_ctx* dup2c = app_ctx->misc;
   if (ring_ge(dup2c->recv_id, bp->ip.ap.fmt.content.clear.id)) {
-    mv_buffer_rtof(app_ctx, fdinfo);
+    mv_buffer_rtof(&app_ctx->br, fdinfo);
     return 0;
   }
 
@@ -34,12 +34,12 @@ int algo_dup2_on_stream(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
   to_fdinfo = evt_core_get_from_url (ctx, url);
   if (to_fdinfo == NULL) {
     fprintf(stderr, "No fd for URL %s in tcp-read. Dropping packet :( \n", url);
-    mv_buffer_wtof (app_ctx, fdinfo);
+    mv_buffer_wtof (&app_ctx->br, fdinfo);
     return 1;
   }
 
   // 2. Move buffer
-  mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo);
+  mv_buffer_rtow (&app_ctx->br, fdinfo, to_fdinfo);
   main_on_udp_write(ctx, to_fdinfo);
   return 0;
 }
@@ -63,12 +63,12 @@ int algo_dup2_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdin
     }
 
     // 2. We move the buffer and notify the target
-    dup_buffer_tow (app_ctx, bp, to_fdinfo);
+    dup_buffer_tow (&app_ctx->br, bp, to_fdinfo);
     main_on_tcp_write(ctx, to_fdinfo);
   }
 
   // 3. Release the buffer
-  mv_buffer_rtof (app_ctx, fdinfo);
+  mv_buffer_rtof (&app_ctx->br, fdinfo);
 
   return 0;
 }
diff --git a/src/algo_naive.c b/src/algo_naive.c
index 90afdaa..6a7bac1 100644
--- a/src/algo_naive.c
+++ b/src/algo_naive.c
@@ -15,12 +15,12 @@ int algo_naive_on_stream(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinf
   to_fdinfo = evt_core_get_from_url (ctx, url);
   if (to_fdinfo == NULL) {
     fprintf(stderr, "No fd for URL %s in tcp-read. Dropping packet :( \n", url);
-    mv_buffer_wtof (app_ctx, fdinfo);
+    mv_buffer_wtof (&app_ctx->br, fdinfo);
     return 1;
   }
 
   // 2. Move buffer
-  mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo);
+  mv_buffer_rtow (&app_ctx->br, fdinfo, to_fdinfo);
   main_on_udp_write(ctx, to_fdinfo);
 
   return 0;
@@ -35,13 +35,13 @@ int algo_naive_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdi
   to_fdinfo = cat->socklist->len > 0 ? g_array_index(cat->socklist, struct evt_core_fdinfo*, 0) : NULL;
   if (to_fdinfo == NULL) {
     fprintf(stderr, "No fd for cat %s in udp-read. Dropping packet :( \n", cat->name);
-    mv_buffer_wtof (app_ctx, fdinfo);
+    mv_buffer_wtof (&app_ctx->br, fdinfo);
     return 1;
   }
   //printf("Pass packet from %s to %s\n", fdinfo->url, url);
 
   // 2. We move the buffer and notify the target
-  mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo);
+  mv_buffer_rtow (&app_ctx->br, fdinfo, to_fdinfo);
   main_on_tcp_write(ctx, to_fdinfo);
 
   return 0;
diff --git a/src/algo_rr.c b/src/algo_rr.c
index f3e004d..712aa52 100644
--- a/src/algo_rr.c
+++ b/src/algo_rr.c
@@ -82,10 +82,10 @@ void rr_pkt_register(struct evt_core_ctx* ctx,  struct evt_core_fdinfo* fdinfo,
     rr->real[real_idx].idx = real_idx;
     rr->real[real_idx].link_fd = fdinfo->fd;
     rr->real[real_idx].algo = app_ctx;
-    mv_buffer_rtoa(app_ctx, fdinfo, &rr->real[real_idx].idx);
+    mv_buffer_rtoa(&app_ctx->br, fdinfo, &rr->real[real_idx].idx);
   } else {
     if (ctx->verbose) fprintf(stdout, "Packet %d already received (current: %d)\n", bp->ip.ap.fmt.content.clear.id, rr->content_id);
-    mv_buffer_rtof (app_ctx, fdinfo);
+    mv_buffer_rtof (&app_ctx->br, fdinfo);
   }
 }
 
@@ -98,7 +98,7 @@ void rr_deliver(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx, struct queue
   dp->on = 0;
 
   // 2. Get the buffer
-  struct buffer_packet* bp = get_app_buffer (app_ctx, &dp->idx);
+  struct buffer_packet* bp = get_app_buffer (&app_ctx->br, &dp->idx);
   assert(bp->ip.ap.fmt.headers.cmd == CMD_CLEAR);
 
   // 3. We update our cursor
@@ -110,12 +110,12 @@ void rr_deliver(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx, struct queue
   if (to_fdinfo == NULL) {
     fprintf(stderr, "No fd for URL %s in udp:write for tcp-read. Dropping packet %d :( \n", url, dp->idx);
     //mv_buffer_wtor (app_ctx, fdinfo, bp);
-    mv_buffer_atof (app_ctx, &dp->idx);
+    mv_buffer_atof (&app_ctx->br, &dp->idx);
   }
 
   // 5. We move the buffer and notify the target
   //mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo, bp);
-  mv_buffer_atow (app_ctx, &dp->idx, to_fdinfo);
+  mv_buffer_atow (&app_ctx->br, &dp->idx, to_fdinfo);
   main_on_udp_write(ctx, to_fdinfo);
 }
 
@@ -164,7 +164,7 @@ void rr_pkt_manage_links(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinf
   set_timeout (ctx, timeout, &rr->wait[idx], on_timeout_health);
 
 release:
-  mv_buffer_rtof(app_ctx, fdinfo);
+  mv_buffer_rtof(&app_ctx->br, fdinfo);
 }
 
 uint64_t rr_pkt_unroll(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx) {
@@ -202,7 +202,7 @@ int algo_rr_on_stream(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo,
     rr_pkt_manage_links(ctx, fdinfo, bp);
   } else {
     fprintf(stderr, "    [algo/rr] Packet CMD unrecognized (%d)\n", bp->ip.ap.fmt.headers.cmd);
-    mv_buffer_rtof(app_ctx, fdinfo);
+    mv_buffer_rtof(&app_ctx->br, fdinfo);
   }
 
   return 0;
@@ -288,7 +288,7 @@ int algo_rr_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
       continue;
     }
 
-    if ((len = write_queue_len (app_ctx, to_fdinfo)) > 0) {
+    if ((len = write_queue_len (&app_ctx->br, to_fdinfo)) > 0) {
       if (ctx->verbose) fprintf(stderr, "    [algo/rr] write queue of %s is not empty (%d), skipping and deactivating\n", to_fdinfo->url, len);
       blacklist_link (rr, sel_link);
       continue;
@@ -296,11 +296,11 @@ int algo_rr_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
 
     if (!app_ctx->ap.is_healing /* if healing deactivated */|| rr->my_links & (1 << sel_link) /* if link not down */ ) {
       rr->current_link = sel_link;
-      mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo);
+      mv_buffer_rtow (&app_ctx->br, fdinfo, to_fdinfo);
       main_on_tcp_write(ctx, to_fdinfo);
       return 0;
     } else {
-      struct buffer_packet* dup_bp = dup_buffer_tow(app_ctx, bp, to_fdinfo);
+      struct buffer_packet* dup_bp = dup_buffer_tow(&app_ctx->br, bp, to_fdinfo);
       /*
        * for later
       dup_bp->ip.ap.fmt.content.health.min_blocked_pkt = 0;
@@ -313,7 +313,7 @@ int algo_rr_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
 not_ready:
   // 3. We find no up target
   fprintf(stderr, "Still bootstrapping or no link to forward data from %s in udp-read. Dropping packet :( \n", fdinfo->url);
-  mv_buffer_wtof (app_ctx, fdinfo);
+  mv_buffer_wtof (&app_ctx->br, fdinfo);
   return 0;
 }
 
diff --git a/src/algo_utils.c b/src/algo_utils.c
index 02ce087..af67e58 100644
--- a/src/algo_utils.c
+++ b/src/algo_utils.c
@@ -1,19 +1,5 @@
 #include "algo_utils.h"
 
-void free_nothing(void* app_ctx) {}
-void free_naive(void* app_ctx) {
-  struct algo_ctx* ctx = (struct algo_ctx*) app_ctx;
-  ctx->ref_count--;
-  if (ctx->ref_count > 0) return;
-  if (ctx->free_misc) ctx->free_misc(ctx->misc);
-  g_queue_free(ctx->free_buffer);
-  g_queue_free(ctx->read_waiting);
-  g_hash_table_destroy (ctx->application_waiting);
-  g_hash_table_destroy (ctx->used_buffer);
-  g_hash_table_destroy (ctx->write_waiting);
-  free(ctx);
-}
-
 void iterate(int* fd, GQueue* q, int* waiting_count) {
   fprintf(stderr, "Queue for fd=%d has length=%d\n", *fd, q->length);
   *waiting_count += q->length;
@@ -23,7 +9,12 @@ void iterate2(int* fd, struct buffer_packet *bp, gpointer user_data) {
   fprintf(stderr, "fd=%d has a used_buffer entry\n", *fd);
 }
 
-void debug_buffer(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) {
+void naive_free_simple(void* v) {
+  GQueue* g = v;
+  g_queue_free (g);
+}
+
+void debug_buffer(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo) {
   fprintf(stderr, "No more free buffer for fd=%d.\n", fdinfo->fd);
   int waiting_count = 0;
   g_hash_table_foreach(app_ctx->write_waiting, (GHFunc)iterate, &waiting_count);
@@ -36,10 +27,30 @@ void debug_buffer(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) {
           waiting_count);
 }
 
+void init_buffer_management(struct buffer_resources* ctx) {
+  ctx->free_buffer = g_queue_new ();
+  ctx->read_waiting = g_queue_new ();
+  ctx->application_waiting = g_hash_table_new (NULL, NULL);
+  ctx->used_buffer = g_hash_table_new(g_int_hash, g_int_equal);
+  ctx->write_waiting = g_hash_table_new_full (g_int_hash, g_int_equal, NULL, naive_free_simple);
+  for (int i = 0; i < sizeof(ctx->bps) / sizeof(ctx->bps[0]); i++) {
+    memset(&(ctx->bps[i]), 0, sizeof(struct buffer_packet));
+    g_queue_push_tail(ctx->free_buffer, &(ctx->bps[i]));
+  }
+}
+
+void destroy_buffer_management(struct buffer_resources* ctx) {
+  g_queue_free(ctx->free_buffer);
+  g_queue_free(ctx->read_waiting);
+  g_hash_table_destroy (ctx->application_waiting);
+  g_hash_table_destroy (ctx->used_buffer);
+  g_hash_table_destroy (ctx->write_waiting);
+}
+
 /**
  * Returns a buffer if available, NULL otherwise
  */
-struct buffer_packet* get_read_buffer(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) {
+struct buffer_packet* get_read_buffer(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo) {
   struct buffer_packet* bp;
 
   // 1. Check if we don't have a buffer
@@ -62,12 +73,12 @@ struct buffer_packet* get_read_buffer(struct algo_ctx *app_ctx, struct evt_core_
   return bp;
 }
 
-void __push_to_free(struct algo_ctx *app_ctx, struct buffer_packet* bp) {
+void __push_to_free(struct buffer_resources *app_ctx, struct buffer_packet* bp) {
   memset(bp, 0, sizeof(struct buffer_packet));
   g_queue_push_tail (app_ctx->free_buffer, bp);
 }
 
-guint write_queue_len(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) {
+guint write_queue_len(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo) {
   GQueue* q;
 
   if ((q = g_hash_table_lookup(app_ctx->write_waiting, &(fdinfo->fd))) == NULL) return 0; // No queue
@@ -77,7 +88,7 @@ guint write_queue_len(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo)
 /**
  * Returns a buffer if available, NULL otherwise
  */
-struct buffer_packet* get_write_buffer(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) {
+struct buffer_packet* get_write_buffer(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo) {
   struct buffer_packet* bp;
   GQueue* q;
 
@@ -98,7 +109,7 @@ struct buffer_packet* get_write_buffer(struct algo_ctx *app_ctx, struct evt_core
   return bp;
 }
 
-void mv_buffer_rtow(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from, struct evt_core_fdinfo* to) {
+void mv_buffer_rtow(struct buffer_resources *app_ctx, struct evt_core_fdinfo* from, struct evt_core_fdinfo* to) {
   GQueue* q;
   struct buffer_packet* bp;
 
@@ -121,7 +132,7 @@ void mv_buffer_rtow(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from, stru
   g_queue_push_tail(q, bp);
 }
 
-void mv_buffer_rtof(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from) {
+void mv_buffer_rtof(struct buffer_resources *app_ctx, struct evt_core_fdinfo* from) {
   struct buffer_packet* bp;
 
   // 1. We get the packet buffer
@@ -134,7 +145,7 @@ void mv_buffer_rtof(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from) {
    __push_to_free (app_ctx, bp);
 }
 
-void mv_buffer_wtof(struct algo_ctx* app_ctx, struct evt_core_fdinfo* fdinfo) {
+void mv_buffer_wtof(struct buffer_resources *app_ctx, struct evt_core_fdinfo* fdinfo) {
   struct buffer_packet* bp = g_hash_table_lookup (app_ctx->used_buffer, &(fdinfo->fd));
   if (bp == NULL) {
     fprintf(stderr, "Unable to find a buffer for fd=%d url=%s in wtof\n", fdinfo->fd, fdinfo->url);
@@ -144,7 +155,7 @@ void mv_buffer_wtof(struct algo_ctx* app_ctx, struct evt_core_fdinfo* fdinfo) {
    __push_to_free (app_ctx, bp);
 }
 
-void mv_buffer_rtoa(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from, void* to) {
+void mv_buffer_rtoa(struct buffer_resources *app_ctx, struct evt_core_fdinfo* from, void* to) {
   struct buffer_packet* bp;
   bp = g_hash_table_lookup (app_ctx->used_buffer, &from->fd);
   if (bp == NULL) {
@@ -159,7 +170,7 @@ void mv_buffer_rtoa(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from, void
   g_hash_table_insert(app_ctx->application_waiting, to, bp);
 }
 
-void mv_buffer_atow(struct algo_ctx* app_ctx, void* from, struct evt_core_fdinfo* to) {
+void mv_buffer_atow(struct buffer_resources *app_ctx, void* from, struct evt_core_fdinfo* to) {
   GQueue* q;
   struct buffer_packet* bp;
 
@@ -182,7 +193,7 @@ void mv_buffer_atow(struct algo_ctx* app_ctx, void* from, struct evt_core_fdinfo
   g_queue_push_tail(q, bp);
 }
 
-void mv_buffer_atof(struct algo_ctx* app_ctx, void* from) {
+void mv_buffer_atof(struct buffer_resources *app_ctx, void* from) {
   struct buffer_packet* bp;
 
   // 1. Remove the buffer
@@ -197,7 +208,7 @@ void mv_buffer_atof(struct algo_ctx* app_ctx, void* from) {
   __push_to_free (app_ctx, bp);
 }
 
-struct buffer_packet* dup_buffer_tow(struct algo_ctx* app_ctx, struct buffer_packet* bp, struct evt_core_fdinfo* to) {
+struct buffer_packet* dup_buffer_tow(struct buffer_resources *app_ctx, struct buffer_packet* bp, struct evt_core_fdinfo* to) {
   GQueue* q;
 
   // 1. We get a free buffer
@@ -222,11 +233,11 @@ struct buffer_packet* dup_buffer_tow(struct algo_ctx* app_ctx, struct buffer_pac
   return bp_dest;
 }
 
-struct buffer_packet* get_app_buffer(struct algo_ctx *app_ctx, void* idx) {
+struct buffer_packet* get_app_buffer(struct buffer_resources *app_ctx, void* idx) {
   return g_hash_table_lookup (app_ctx->application_waiting, idx);
 }
 
-void notify_read(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx) {
+void notify_read(struct evt_core_ctx* ctx, struct buffer_resources* app_ctx) {
   struct evt_core_fdinfo* next_fdinfo = NULL;
   while (next_fdinfo == NULL) {
     int* fd = g_queue_pop_head(app_ctx->read_waiting);
@@ -252,9 +263,3 @@ int append_buffer(union abstract_packet* dest, int pos, union abstract_packet* s
   memcpy(target, src, src->fmt.headers.size);
   return 0;
 }
-
-void naive_free_simple(void* v) {
-  GQueue* g = v;
-  g_queue_free (g);
-}
-
diff --git a/src/algo_utils.h b/src/algo_utils.h
index 1952554..f2845d1 100644
--- a/src/algo_utils.h
+++ b/src/algo_utils.h
@@ -6,62 +6,31 @@
 #include "evt_core.h"
 #define PACKET_BUFFER_SIZE 1024
 
-struct algo_params {
-  uint8_t is_waiting_bootstrap;
-  uint8_t is_healing;
-  char* algo_name;
-  int links, fresh_data, redundant_data;
-};
-
-
-struct algo_ctx;
-typedef void (*algo_init)(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx, struct algo_params* ap);
-typedef int  (*algo_ctx_on_buffer)(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct buffer_packet* bp);
-typedef int  (*algo_ctx_on_event)(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo);
-
-typedef void (*algo_ctx_free_misc)(void*);
-
-struct algo_desc {
-  char* name;
-  algo_init init;
-  algo_ctx_on_buffer on_stream;
-  algo_ctx_on_buffer on_datagram;
-  algo_ctx_on_event on_err;
-};
-
-struct algo_ctx {
-  struct algo_desc* desc;
-  uint8_t link_count;
-  uint8_t is_rdy;
-  struct algo_params ap;
-  int ref_count;
+struct buffer_resources {
   struct buffer_packet bps[PACKET_BUFFER_SIZE];
   GQueue* free_buffer;              // Available buffers
   GHashTable* used_buffer;          // Buffers used for reading or writing
   GQueue* read_waiting;             // Who wait to be notified for a read
   GHashTable* application_waiting;  // Structure that can be used by the algo for its internal logic
   GHashTable* write_waiting;        // Structure to track packets waiting to be written
-  void* misc;                       // Additional structures
-  algo_ctx_free_misc free_misc;     // Fx ptr to free misc
 };
 
-void mv_buffer_rtow(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from, struct evt_core_fdinfo* to);
-void mv_buffer_rtof(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from);
-void mv_buffer_wtof(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from);
-void mv_buffer_rtoa(struct algo_ctx* app_ctx, struct evt_core_fdinfo* from, void* to);
-void mv_buffer_atow(struct algo_ctx* app_ctx, void* from, struct evt_core_fdinfo* to);
-void mv_buffer_atof(struct algo_ctx* app_ctx, void* from);
-struct buffer_packet* dup_buffer_tow(struct algo_ctx* app_ctx, struct buffer_packet* bp, struct evt_core_fdinfo* to);
-guint write_queue_len(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo);
+void init_buffer_management(struct buffer_resources* br);
+void destroy_buffer_management(struct buffer_resources* br);
+void mv_buffer_rtow(struct buffer_resources* app_ctx, struct evt_core_fdinfo* from, struct evt_core_fdinfo* to);
+void mv_buffer_rtof(struct buffer_resources* app_ctx, struct evt_core_fdinfo* from);
+void mv_buffer_wtof(struct buffer_resources* app_ctx, struct evt_core_fdinfo* from);
+void mv_buffer_rtoa(struct buffer_resources* app_ctx, struct evt_core_fdinfo* from, void* to);
+void mv_buffer_atow(struct buffer_resources* app_ctx, void* from, struct evt_core_fdinfo* to);
+void mv_buffer_atof(struct buffer_resources* app_ctx, void* from);
+struct buffer_packet* dup_buffer_tow(struct buffer_resources* app_ctx, struct buffer_packet* bp, struct evt_core_fdinfo* to);
+guint write_queue_len(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo);
 
 int append_buffer(union abstract_packet* dest, int pos, union abstract_packet* src);
 
-struct buffer_packet* get_write_buffer(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo);
-struct buffer_packet* get_read_buffer(struct algo_ctx *app_ctx, struct evt_core_fdinfo *fdinfo);
-struct buffer_packet* get_app_buffer(struct algo_ctx *app_ctx, void* idx);
+struct buffer_packet* get_write_buffer(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo);
+struct buffer_packet* get_read_buffer(struct buffer_resources *app_ctx, struct evt_core_fdinfo *fdinfo);
+struct buffer_packet* get_app_buffer(struct buffer_resources *app_ctx, void* idx);
 
-void notify_read(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx);
+void notify_read(struct evt_core_ctx* ctx, struct buffer_resources* app_ctx);
 
-void free_naive(void* app_ctx);
-void free_nothing(void* app_ctx);
-void naive_free_simple(void* v);
diff --git a/src/capture_traffic.c b/src/capture_traffic.c
new file mode 100644
index 0000000..c431e8c
--- /dev/null
+++ b/src/capture_traffic.c
@@ -0,0 +1,8 @@
+#include "capture_traffic.h"
+void init_traffic_capture(struct capture_ctx* ctx) {
+
+}
+
+void stop_traffic_capture(struct capture_ctx* ctx) {
+
+}
diff --git a/src/capture_traffic.h b/src/capture_traffic.h
new file mode 100644
index 0000000..7024248
--- /dev/null
+++ b/src/capture_traffic.h
@@ -0,0 +1,14 @@
+#pragma once
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/signalfd.h>
+#include <errno.h>
+#include "evt_core.h"
+
+struct capture_ctx {
+
+};
+
+void init_traffic_capture(struct capture_ctx* ctx);
+void stop_traffic_capture(struct capture_ctx* ctx);
diff --git a/src/donar.c b/src/donar.c
index d9dd2d5..1fc6402 100644
--- a/src/donar.c
+++ b/src/donar.c
@@ -14,7 +14,7 @@ int main(int argc, char** argv) {
     struct donar_params dp = {0};
     donar_init_params (&dp);
 
-    while ((dp.opt = getopt(argc, argv, "vcse:r:o:a:bhl:d:")) != -1) {
+    while ((dp.opt = getopt(argc, argv, "vcse:r:o:a:bhl:d:f:")) != -1) {
       switch(dp.opt) {
       case 'v':
         dp.verbose++;
@@ -53,6 +53,9 @@ int main(int argc, char** argv) {
       case 'd':
         sscanf(optarg, "%d,%d", &dp.fresh_data, &dp.redundant_data);
         break;
+      case 'f':
+        dp.capture_file = strdup(optarg);
+        break;
       default:
         goto in_error;
       }
@@ -74,14 +77,16 @@ int main(int argc, char** argv) {
 
 in_error:
     dp.errored = 1;
-    fprintf(stderr, "Usage as client : %s -c -a <algo> -o <onion service file> [-h] [-b] [-l <links>] [-d <fresh>,<red>] [-e <exposed udp port>]* [-r <remote udp port>]*\n", argv[0]);
-    fprintf(stderr, "Usage as server : %s -s -a <algo> [-h] [-b] [-l <links>] [-d <fresh>,<red>] [-e <exposed udp port>]* [-r <remote udp port>]*\n\n", argv[0]);
+    fprintf(stderr, "Usage as client : %s -c -a <algo> -o <onion service file> [-h] [-b] [-f <dump packets>] [-l <links>] [-d <fresh>,<red>] [-e <exposed udp port>]* [-r <remote udp port>]*\n", argv[0]);
+    fprintf(stderr, "Usage as server : %s -s -a <algo> [-h] [-b] [-l <links>] [-f <dump_packets>] [-d <fresh>,<red>] [-e <exposed udp port>]* [-r <remote udp port>]*\n\n", argv[0]);
     fprintf(stderr, "Passed parameters: client=%d, server=%d, algo=%s, exposed_ports=%d, remote_ports=%d, onion_file=%s, links=%d, duplication=%d,%d\n",
             dp.is_client, dp.is_server, dp.algo, dp.exposed_ports->len, dp.remote_ports->len, dp.onion_file, dp.links, dp.fresh_data, dp.redundant_data);
 
 terminate:
     if (dp.onion_file != NULL) free(dp.onion_file);
     if (dp.algo != NULL) free(dp.algo);
+    if (dp.capture_file != NULL) free(dp.capture_file);
+
     g_ptr_array_free(dp.exposed_ports, TRUE);
     g_ptr_array_free(dp.remote_ports, TRUE);
 
diff --git a/src/donar_client.c b/src/donar_client.c
index 1a46aac..cef5dc3 100644
--- a/src/donar_client.c
+++ b/src/donar_client.c
@@ -76,7 +76,8 @@ void donar_client(struct donar_client_ctx* ctx, struct donar_params* dp) {
     .algo_name = dp->algo,
     .links = dp->links,
     .fresh_data = dp->fresh_data,
-    .redundant_data = dp->redundant_data
+    .redundant_data = dp->redundant_data,
+    .capture_file = dp->capture_file
   };
 
   evt_core_init (&(ctx->evts), dp->verbose);
diff --git a/src/donar_init.c b/src/donar_init.c
index 3beaa39..5d21c9e 100644
--- a/src/donar_init.c
+++ b/src/donar_init.c
@@ -146,6 +146,7 @@ void free_port (void* ptr) {
 void donar_init_params(struct donar_params* dp) {
   dp->onion_file = NULL;
   dp->algo = NULL;
+  dp->capture_file = NULL;
   dp->is_server = 0;
   dp->is_client = 0;
   dp->is_healing = 0;
diff --git a/src/donar_init.h b/src/donar_init.h
index c423f3f..3629fd7 100644
--- a/src/donar_init.h
+++ b/src/donar_init.h
@@ -10,7 +10,7 @@
 
 struct donar_params {
   int opt, is_server, is_client, is_waiting_bootstrap, is_healing, errored, verbose, links, fresh_data, redundant_data;
-  char *port, *onion_file, *algo;
+  char *port, *onion_file, *algo, *capture_file;
   GPtrArray *remote_ports, *exposed_ports;
 };
 
diff --git a/src/donar_server.c b/src/donar_server.c
index f8b7c8a..e403672 100644
--- a/src/donar_server.c
+++ b/src/donar_server.c
@@ -58,7 +58,8 @@ void donar_server(struct donar_server_ctx* ctx,  struct donar_params* dp) {
     .algo_name = dp->algo,
     .links = dp->links,
     .fresh_data = dp->fresh_data,
-    .redundant_data = dp->redundant_data
+    .redundant_data = dp->redundant_data,
+    .capture_file = dp->capture_file
   };
 
   evt_core_init (&(ctx->evts), dp->verbose);
diff --git a/src/proxy.c b/src/proxy.c
index 45c3c9c..d918700 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -44,7 +44,7 @@ int main_on_tcp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   int read_res = FDS_READY;
 
   if (ctx->verbose > 1) fprintf(stderr, "  [proxy] Get current read buffer OR a new read buffer OR subscribe to be notified later\n");
-  if ((bp = get_read_buffer(app_ctx, fdinfo)) == NULL) return 1;
+  if ((bp = get_read_buffer(&app_ctx->br, fdinfo)) == NULL) return 1;
 
   if (ctx->verbose > 1) fprintf(stderr, "  [proxy] Try to read a whole packet in the buffer\n");
   while (bp->mode == BP_READING) {
@@ -69,7 +69,7 @@ int main_on_udp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   char url[255];
 
   // 1. Get current read buffer OR a new read buffer OR subscribe to be notified later
-  if ((bp = get_read_buffer(app_ctx, fdinfo)) == NULL) return 1;
+  if ((bp = get_read_buffer(&app_ctx->br, fdinfo)) == NULL) return 1;
 
   // 2. Read packet from socket
   bp->ip.ap.fmt.content.clear.port = url_get_port_int (fdinfo->url);
@@ -98,7 +98,7 @@ int main_on_tcp_write(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo)
   app_ctx->is_rdy = app_ctx->is_rdy || is_rdy; // @FIXME prevent deactivation for our tests
 
   // 1. Get current write buffer OR a buffer from the waiting queue OR leave
-  if ((bp = get_write_buffer(app_ctx, fdinfo)) == NULL) return 1;
+  if ((bp = get_write_buffer(&app_ctx->br, fdinfo)) == NULL) return 1;
 
   // 2. Write data from the buffer to the socket
   while (bp->mode == BP_WRITING) {
@@ -109,8 +109,8 @@ int main_on_tcp_write(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo)
 
   // 3. A whole packet has been written
   // Release the buffer and notify
-  mv_buffer_wtof(app_ctx, fdinfo);
-  notify_read(ctx, app_ctx);
+  mv_buffer_wtof(&app_ctx->br, fdinfo);
+  notify_read(ctx, &app_ctx->br);
 
   return 0;
 co_error:
@@ -125,7 +125,7 @@ int main_on_udp_write (struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo)
   int write_res = FDS_READY;
 
   // 1. Get current write buffer OR a buffer from the waiting queue OR leave
-  if ((bp = get_write_buffer(app_ctx, fdinfo)) == NULL) return 1;
+  if ((bp = get_write_buffer(&app_ctx->br, fdinfo)) == NULL) return 1;
 
   // 2. Write buffer
   write_res = write_packet_to_udp(fdinfo->fd, bp, fdinfo->other);
@@ -134,8 +134,8 @@ int main_on_udp_write (struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo)
 
   // 3. A whole packet has been written
   // Release the buffer and notify
-  mv_buffer_wtof(app_ctx, fdinfo);
-  notify_read(ctx, app_ctx);
+  mv_buffer_wtof(&app_ctx->br, fdinfo);
+  notify_read(ctx, &app_ctx->br);
 
   return 0;
 co_error:
@@ -148,41 +148,43 @@ int main_on_err(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   struct buffer_packet* bp;
 
   // 1. If has a "used" buffer, remove it
-  mv_buffer_rtof (app_ctx, fdinfo);
+  mv_buffer_rtof (&app_ctx->br, fdinfo);
 
   // 2. If appears in the write waiting queue, remove it
-  while (get_write_buffer (app_ctx, fdinfo) != NULL) {
-    mv_buffer_wtof(app_ctx, fdinfo);
+  while (get_write_buffer (&app_ctx->br, fdinfo) != NULL) {
+    mv_buffer_wtof(&app_ctx->br, fdinfo);
   }
 
   // 3. If appears in the read waiting queue, remove it
-  g_queue_remove_all (app_ctx->read_waiting, &(fdinfo->fd));
+  g_queue_remove_all (app_ctx->br.read_waiting, &(fdinfo->fd));
 
   return app_ctx->desc->on_err(ctx, fdinfo);
 }
 
+void algo_main_destroy(void* app_ctx) {
+  struct algo_ctx* ctx = (struct algo_ctx*) app_ctx;
+  ctx->ref_count--;
+  if (ctx->ref_count > 0) return;
+
+  stop_traffic_capture(&ctx->cap);
+  destroy_buffer_management(&ctx->br);
+  if (ctx->free_misc) ctx->free_misc(ctx->misc);
+  free(ctx);
+}
+
 void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap) {
   struct algo_ctx* ctx = malloc(sizeof(struct algo_ctx));
   if (ctx == NULL) goto init_err;
   memset(ctx, 0, sizeof(struct algo_ctx));
-  ctx->free_buffer = g_queue_new ();
-  ctx->read_waiting = g_queue_new ();
-  ctx->application_waiting = g_hash_table_new (NULL, NULL);
-  ctx->used_buffer = g_hash_table_new(g_int_hash, g_int_equal);
-  ctx->write_waiting = g_hash_table_new_full (g_int_hash, g_int_equal, NULL, naive_free_simple);
   ctx->link_count = 8;
   ctx->is_rdy = 0;
   ctx->ap = *ap;
-  for (int i = 0; i < sizeof(ctx->bps) / sizeof(ctx->bps[0]); i++) {
-    memset(&(ctx->bps[i]), 0, sizeof(struct buffer_packet));
-    g_queue_push_tail(ctx->free_buffer, &(ctx->bps[i]));
-  }
 
   struct evt_core_cat tcp_listen = {
     .name = "tcp-listen",
     .flags = EPOLLIN,
     .app_ctx = ctx,
-    .free_app_ctx = free_naive,
+    .free_app_ctx = algo_main_destroy,
     .cb = main_on_tcp_co,
     .err_cb = NULL
   };
@@ -193,7 +195,7 @@ void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap) {
     .name = "tcp-read",
     .flags = EPOLLIN | EPOLLET | EPOLLRDHUP,
     .app_ctx = ctx,
-    .free_app_ctx = free_naive,
+    .free_app_ctx = algo_main_destroy,
     .cb = main_on_tcp_read,
     .err_cb = main_on_err
   };
@@ -204,7 +206,7 @@ void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap) {
     .name = "udp-read",
     .flags = EPOLLIN | EPOLLET | EPOLLRDHUP,
     .app_ctx = ctx,
-    .free_app_ctx = free_naive,
+    .free_app_ctx = algo_main_destroy,
     .cb = main_on_udp_read,
     .err_cb = main_on_err
   };
@@ -215,7 +217,7 @@ void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap) {
     .name = "tcp-write",
     .flags = EPOLLOUT | EPOLLET | EPOLLRDHUP,
     .app_ctx = ctx,
-    .free_app_ctx = free_naive,
+    .free_app_ctx = algo_main_destroy,
     .cb = main_on_tcp_write,
     .err_cb = main_on_err
   };
@@ -226,13 +228,16 @@ void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap) {
     .name = "udp-write",
     .flags = EPOLLOUT | EPOLLET,
     .app_ctx = ctx,
-    .free_app_ctx = free_naive,
+    .free_app_ctx = algo_main_destroy,
     .cb = main_on_udp_write,
     .err_cb = main_on_err
   };
   ctx->ref_count++;
   evt_core_add_cat(evt, &udp_write);
 
+  init_buffer_management(&ctx->br);
+  init_traffic_capture(&ctx->cap);
+
   for (int i = 0; i < sizeof(available_algo) / sizeof(available_algo[0]); i++) {
     if (strcmp(available_algo[i].name, ap->algo_name) == 0) {
       ctx->desc = &(available_algo[i]);
diff --git a/src/proxy.h b/src/proxy.h
index 5d7e082..fc9ab61 100644
--- a/src/proxy.h
+++ b/src/proxy.h
@@ -6,10 +6,45 @@
 #include <string.h>
 #include "evt_core.h"
 #include "algo_utils.h"
+#include "capture_traffic.h"
 #include "url.h"
 #include "utils.h"
 #include "packet.h"
 
+struct algo_params {
+  uint8_t is_waiting_bootstrap;
+  uint8_t is_healing;
+  char *algo_name, *capture_file;
+  int links, fresh_data, redundant_data;
+};
+
+struct algo_ctx;
+typedef void (*algo_init)(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx, struct algo_params* ap);
+typedef int  (*algo_ctx_on_buffer)(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct buffer_packet* bp);
+typedef int  (*algo_ctx_on_event)(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo);
+
+typedef void (*algo_ctx_free_misc)(void*);
+
+struct algo_desc {
+  char* name;
+  algo_init init;
+  algo_ctx_on_buffer on_stream;
+  algo_ctx_on_buffer on_datagram;
+  algo_ctx_on_event on_err;
+};
+
+struct algo_ctx {
+  struct algo_desc* desc;
+  uint8_t link_count;
+  uint8_t is_rdy;
+  struct algo_params ap;
+  int ref_count;
+  struct capture_ctx cap;
+  struct buffer_resources br;
+  void* misc;                       // Additional structures
+  algo_ctx_free_misc free_misc;     // Fx ptr to free misc
+};
+
 void algo_naive_init(struct evt_core_ctx* ctx, struct algo_ctx* app_ctx, struct algo_params* ap);
 int  algo_naive_on_stream(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct buffer_packet* bp);
 int  algo_naive_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo, struct buffer_packet* bp);
@@ -49,7 +84,6 @@ static struct algo_desc available_algo[] = {
   }
 };
 
-
 void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap);
 
 int main_on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo);

From 7e2a7449c6ba7d9c5bec7bf256f75002441a1ec1 Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Mon, 27 May 2019 18:14:21 +0200
Subject: [PATCH 2/7] WIP capture traffic

---
 src/capture_traffic.c | 17 +++++++++++++++--
 src/capture_traffic.h | 23 ++++++++++++++++++-----
 src/proxy.c           |  4 ++--
 3 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/src/capture_traffic.c b/src/capture_traffic.c
index c431e8c..a5ab0fa 100644
--- a/src/capture_traffic.c
+++ b/src/capture_traffic.c
@@ -1,8 +1,21 @@
 #include "capture_traffic.h"
-void init_traffic_capture(struct capture_ctx* ctx) {
+void traffic_capture_init(struct capture_ctx* ctx, char* filename) {
+  ctx->activated = filename == NULL ? 0 : 1;
+  if (!ctx->activated) return;
 
+  ctx->filename = strdup(filename);
+  ctx->capture_in = g_queue_new ();
+  ctx->capture_out = g_queue_new ();
 }
 
-void stop_traffic_capture(struct capture_ctx* ctx) {
+void traffic_capture_stop(struct capture_ctx* ctx) {
+  if (!ctx->activated) return;
 
+  FILE* fd = NULL;
+
+  if ((fd = fopen(ctx->filename, "w")) == NULL) {
+
+  }
+
+  free(ctx->filename);
 }
diff --git a/src/capture_traffic.h b/src/capture_traffic.h
index 7024248..6210b14 100644
--- a/src/capture_traffic.h
+++ b/src/capture_traffic.h
@@ -2,13 +2,26 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
-#include <sys/signalfd.h>
+#include <glib-2.0/glib.h>
+#include <glib-2.0/gmodule.h>
+#include <glib-2.0/glib-object.h>
 #include <errno.h>
 #include "evt_core.h"
 
-struct capture_ctx {
-
+struct captured_packet {
+  struct timeval* captured_time;
+  char* pkt;
 };
 
-void init_traffic_capture(struct capture_ctx* ctx);
-void stop_traffic_capture(struct capture_ctx* ctx);
+struct capture_ctx {
+  uint8_t activated;
+  char* filename;
+  struct timeval* start_time;
+  GQueue* capture_in;
+  GQueue* capture_out;
+};
+
+void traffic_capture_init(struct capture_ctx* ctx, char* filename);
+void traffic_capture_stop(struct capture_ctx* ctx);
+void traffic_capture_notify_in(struct capture_ctx* ctx);
+void traffic_capture_notify_out(struct capture_ctx* ctx);
diff --git a/src/proxy.c b/src/proxy.c
index d918700..45df7bf 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -166,7 +166,7 @@ void algo_main_destroy(void* app_ctx) {
   ctx->ref_count--;
   if (ctx->ref_count > 0) return;
 
-  stop_traffic_capture(&ctx->cap);
+  traffic_capture_stop(&ctx->cap);
   destroy_buffer_management(&ctx->br);
   if (ctx->free_misc) ctx->free_misc(ctx->misc);
   free(ctx);
@@ -236,7 +236,7 @@ void algo_main_init(struct evt_core_ctx* evt, struct algo_params* ap) {
   evt_core_add_cat(evt, &udp_write);
 
   init_buffer_management(&ctx->br);
-  init_traffic_capture(&ctx->cap);
+  traffic_capture_init(&ctx->cap, ap->capture_file);
 
   for (int i = 0; i < sizeof(available_algo) / sizeof(available_algo[0]); i++) {
     if (strcmp(available_algo[i].name, ap->algo_name) == 0) {

From 5be3a951afbc3ba7ae08d4b7c4a80a0e5e9a5f92 Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Tue, 28 May 2019 11:45:20 +0200
Subject: [PATCH 3/7] Gathering code should work

---
 src/capture_traffic.c | 48 +++++++++++++++++++++++++++++++++++++++++--
 src/capture_traffic.h | 18 ++++++++++++----
 src/packet.h          |  1 +
 src/proxy.c           | 10 +++++++--
 4 files changed, 69 insertions(+), 8 deletions(-)

diff --git a/src/capture_traffic.c b/src/capture_traffic.c
index a5ab0fa..544f11c 100644
--- a/src/capture_traffic.c
+++ b/src/capture_traffic.c
@@ -1,11 +1,55 @@
 #include "capture_traffic.h"
+
+void dynbuf_init(struct dynbuf* db) {
+  db->content = malloc(MEGABYTE);
+  if (db->content == NULL) {
+    perror("malloc dynbuf failed");
+    exit(EXIT_FAILURE);
+  }
+  db->written = 0;
+  db->alloced = MEGABYTE;
+}
+
+void dynbuf_check_alloc(struct dynbuf* db, size_t len) {
+    if (db->written + len > db->alloced) {
+    size_t new_alloced = db->written + len > 2 * db->alloced ? db->written + len : 2 * db->alloced;
+    db->content = realloc(db->content, new_alloced);
+    if (db->content == NULL) {
+      perror("realloc dynbuf failed");
+      exit(EXIT_FAILURE);
+    }
+    db->alloced = new_alloced;
+  }
+}
+
+void dynbuf_append(struct dynbuf* db, char* ptr, size_t len) {
+  dynbuf_check_alloc(db, len);
+
+  memcpy(db->content + db->written, ptr, len);
+  db->written += len;
+}
+
 void traffic_capture_init(struct capture_ctx* ctx, char* filename) {
   ctx->activated = filename == NULL ? 0 : 1;
   if (!ctx->activated) return;
 
   ctx->filename = strdup(filename);
-  ctx->capture_in = g_queue_new ();
-  ctx->capture_out = g_queue_new ();
+  dynbuf_init (&ctx->in);
+  dynbuf_init (&ctx->out);
+}
+
+void traffic_capture_notify(struct capture_ctx* ctx, struct buffer_packet *bp, char* dest) {
+  if (!ctx->activated) return;
+
+  if (clock_gettime(CLOCK_MONOTONIC, &bp->seen) == -1){
+    perror("clock_gettime error");
+    exit(EXIT_FAILURE);
+  }
+
+  dynbuf_append (
+    strcmp(dest, "in") == 0 ? &ctx->in : &ctx->out,
+    (char*)&bp,
+    sizeof(struct buffer_packet) - sizeof(struct internet_packet) + bp->ip.ap.fmt.headers.size);
 }
 
 void traffic_capture_stop(struct capture_ctx* ctx) {
diff --git a/src/capture_traffic.h b/src/capture_traffic.h
index 6210b14..df4ee89 100644
--- a/src/capture_traffic.h
+++ b/src/capture_traffic.h
@@ -6,22 +6,32 @@
 #include <glib-2.0/gmodule.h>
 #include <glib-2.0/glib-object.h>
 #include <errno.h>
+#include "packet.h"
 #include "evt_core.h"
 
+#define KILOBYTE 1024l
+#define MEGABYTE 1024l * KILOBYTE
+#define GIGABYTE 1024l * MEGABYTE
+
 struct captured_packet {
   struct timeval* captured_time;
   char* pkt;
 };
 
+struct dynbuf {
+  char* content;
+  size_t written;
+  size_t alloced;
+};
+
 struct capture_ctx {
   uint8_t activated;
   char* filename;
   struct timeval* start_time;
-  GQueue* capture_in;
-  GQueue* capture_out;
+  struct dynbuf in;
+  struct dynbuf out;
 };
 
 void traffic_capture_init(struct capture_ctx* ctx, char* filename);
 void traffic_capture_stop(struct capture_ctx* ctx);
-void traffic_capture_notify_in(struct capture_ctx* ctx);
-void traffic_capture_notify_out(struct capture_ctx* ctx);
+void traffic_capture_notify(struct capture_ctx* ctx, struct buffer_packet *bp, char* dest);
diff --git a/src/packet.h b/src/packet.h
index 6f161e2..a8e78a8 100644
--- a/src/packet.h
+++ b/src/packet.h
@@ -70,6 +70,7 @@ struct buffer_packet {
   uint8_t ap_count;
   uint16_t aread;
   uint16_t awrite;
+  struct timespec seen;
   struct internet_packet ip;
 };
 
diff --git a/src/proxy.c b/src/proxy.c
index 45df7bf..afe9772 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -77,7 +77,10 @@ int main_on_udp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
   if (read_res == FDS_ERR) goto co_error;
   if (read_res == FDS_AGAIN) return 1;
 
-  // 3. Apply logic
+  // 3. Notify helpers
+  traffic_capture_notify (&app_ctx->cap, bp, "in");
+
+  // 4. Apply logic
   return app_ctx->desc->on_datagram(ctx, fdinfo, bp);
 
 co_error:
@@ -132,7 +135,10 @@ int main_on_udp_write (struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo)
   if (write_res == FDS_ERR) goto co_error;
   if (write_res == FDS_AGAIN) return 1;
 
-  // 3. A whole packet has been written
+  // 3. Notify helpers
+  traffic_capture_notify (&app_ctx->cap, bp, "out");
+
+  // 4. A whole packet has been written
   // Release the buffer and notify
   mv_buffer_wtof(&app_ctx->br, fdinfo);
   notify_read(ctx, &app_ctx->br);

From 6b4a784171ead851cd2c278cec0927c05e71ffa6 Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Tue, 28 May 2019 14:21:06 +0200
Subject: [PATCH 4/7] Write packets to files

---
 src/capture_traffic.c | 29 +++++++++++++++++++++++++++--
 src/capture_traffic.h |  2 ++
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/src/capture_traffic.c b/src/capture_traffic.c
index 544f11c..eee7baf 100644
--- a/src/capture_traffic.c
+++ b/src/capture_traffic.c
@@ -29,6 +29,10 @@ void dynbuf_append(struct dynbuf* db, char* ptr, size_t len) {
   db->written += len;
 }
 
+void dynbuf_destroy(struct dynbuf* db) {
+  free(db->content);
+}
+
 void traffic_capture_init(struct capture_ctx* ctx, char* filename) {
   ctx->activated = filename == NULL ? 0 : 1;
   if (!ctx->activated) return;
@@ -49,7 +53,7 @@ void traffic_capture_notify(struct capture_ctx* ctx, struct buffer_packet *bp, c
   dynbuf_append (
     strcmp(dest, "in") == 0 ? &ctx->in : &ctx->out,
     (char*)&bp,
-    sizeof(struct buffer_packet) - sizeof(struct internet_packet) + bp->ip.ap.fmt.headers.size);
+    sizeof(struct buffer_packet));
 }
 
 void traffic_capture_stop(struct capture_ctx* ctx) {
@@ -57,8 +61,29 @@ void traffic_capture_stop(struct capture_ctx* ctx) {
 
   FILE* fd = NULL;
 
-  if ((fd = fopen(ctx->filename, "w")) == NULL) {
+  struct dynbuf *dbs[] = {&ctx->in, &ctx->out};
+  for (int i = 0; i < 2; i++) {
+    size_t written = 0, ack = 0;
+    char *out_file = NULL;
 
+    asprintf(&out_file, "%s.%d", ctx->filename, i);
+    if (out_file == NULL || (fd = fopen(out_file, "w")) == NULL) {
+      perror("failed to open file");
+      exit(EXIT_FAILURE);
+    }
+    free(out_file);
+
+    while (written < dbs[i]->written) {
+      ack = fwrite(dbs[i]->content+written, sizeof(char), dbs[i]->written, fd);
+      if (ack <= 0) {
+        perror("unable to write capture file");
+        exit(EXIT_FAILURE);
+      }
+      written += ack;
+    }
+
+    fclose(fd);
+    dynbuf_destroy (dbs[i]);
   }
 
   free(ctx->filename);
diff --git a/src/capture_traffic.h b/src/capture_traffic.h
index df4ee89..ccdabcf 100644
--- a/src/capture_traffic.h
+++ b/src/capture_traffic.h
@@ -1,4 +1,6 @@
 #pragma once
+#define _GNU_SOURCE
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>

From 4582d4a9d2bd496f7c69699105703a9c719e989e Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Tue, 28 May 2019 15:47:31 +0200
Subject: [PATCH 5/7] Fix capture + send data

---
 src/capture_traffic.c |  2 +-
 src/meas_lat.c        | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/capture_traffic.c b/src/capture_traffic.c
index eee7baf..d1f0522 100644
--- a/src/capture_traffic.c
+++ b/src/capture_traffic.c
@@ -52,7 +52,7 @@ void traffic_capture_notify(struct capture_ctx* ctx, struct buffer_packet *bp, c
 
   dynbuf_append (
     strcmp(dest, "in") == 0 ? &ctx->in : &ctx->out,
-    (char*)&bp,
+    (char*)bp,
     sizeof(struct buffer_packet));
 }
 
diff --git a/src/meas_lat.c b/src/meas_lat.c
index 42961c2..2565a0e 100644
--- a/src/meas_lat.c
+++ b/src/meas_lat.c
@@ -41,6 +41,7 @@ struct measure_conf* create_measure_conf(int max_mes, int plsize) {
     perror("malloc failed");
     exit(EXIT_FAILURE);
   }
+
   return mc;
 }
 
@@ -114,6 +115,15 @@ int on_timer(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
     perror("clock_gettime error");
     exit(EXIT_FAILURE);
   }
+
+  char *my_msg = "Tu n'es pas tout a fait la misere,\nCar les levres les plus pauvres te denoncent\nPar un sourire.";
+  size_t msg_len = strlen(my_msg);
+  size_t cursor_msg = 0;
+  for (size_t i = sizeof(struct packet_header); i < mc->payload_size; i++) {
+    mc->payload[i] = my_msg[cursor_msg];
+    cursor_msg = (cursor_msg + 1) % msg_len;
+  }
+
   struct evt_core_fdinfo* tgtinfo = evt_core_get_first_from_cat (ctx, "udp-read");
   if (tgtinfo == NULL) tgtinfo = evt_core_get_first_from_cat (ctx, "tcp-read");
   if (tgtinfo == NULL) {

From c937c72b8af5c3ee88c7416b80cfae581331bd52 Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Tue, 28 May 2019 16:13:42 +0200
Subject: [PATCH 6/7] Fix not found bug

---
 src/algo_utils.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/algo_utils.c b/src/algo_utils.c
index af67e58..3813a6d 100644
--- a/src/algo_utils.c
+++ b/src/algo_utils.c
@@ -139,6 +139,7 @@ void mv_buffer_rtof(struct buffer_resources *app_ctx, struct evt_core_fdinfo* fr
   bp = g_hash_table_lookup (app_ctx->used_buffer, &from->fd);
   if (bp == NULL) {
     fprintf(stderr, "Unable to find a buffer for fd=%d url=%s in rtof\n", from->fd, from->url);
+    return;
   }
   g_hash_table_remove(app_ctx->used_buffer, &(from->fd));
 
@@ -149,6 +150,7 @@ void mv_buffer_wtof(struct buffer_resources *app_ctx, struct evt_core_fdinfo* fd
   struct buffer_packet* bp = g_hash_table_lookup (app_ctx->used_buffer, &(fdinfo->fd));
   if (bp == NULL) {
     fprintf(stderr, "Unable to find a buffer for fd=%d url=%s in wtof\n", fdinfo->fd, fdinfo->url);
+    return;
   }
   g_hash_table_remove(app_ctx->used_buffer, &(fdinfo->fd));
 

From d53f58f56812adb68e8c48c0aa3d3cb9390fdc50 Mon Sep 17 00:00:00 2001
From: Quentin Dufour <quentin@deuxfleurs.fr>
Date: Tue, 28 May 2019 17:15:37 +0200
Subject: [PATCH 7/7] Add capdiff to see differences between captures

---
 CMakeLists.txt |  6 +++-
 src/capdiff.c  | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 92 insertions(+), 1 deletion(-)
 create mode 100644 src/capdiff.c

diff --git a/CMakeLists.txt b/CMakeLists.txt
index caeef5f..1182bb3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,6 +41,7 @@ add_executable(donar ${CSOURCES} src/donar.c)
 add_executable(measlat ${CSOURCES} src/meas_lat.c)
 add_executable(udpecho ${CSOURCES} src/udp_echo.c)
 add_executable(torecho ${CSOURCES} src/tor_echo.c)
+add_executable(capdiff ${CSOURCES} src/capdiff.c)
 
 find_package(PkgConfig REQUIRED)
 pkg_search_module(GLIB REQUIRED glib-2.0)
@@ -57,6 +58,9 @@ target_link_libraries(udpecho ${GLIB_LDFLAGS})
 target_include_directories(torecho PRIVATE ${GLIB_INCLUDE_DIRS})
 target_link_libraries(torecho ${GLIB_LDFLAGS})
 
-install(TARGETS donar measlat udpecho torecho
+target_include_directories(capdiff PRIVATE ${GLIB_INCLUDE_DIRS})
+target_link_libraries(capdiff ${GLIB_LDFLAGS})
+
+install(TARGETS donar measlat udpecho torecho capdiff
         RUNTIME DESTINATION bin
         LIBRARY DESTINATION lib)
diff --git a/src/capdiff.c b/src/capdiff.c
new file mode 100644
index 0000000..0912c23
--- /dev/null
+++ b/src/capdiff.c
@@ -0,0 +1,87 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include "packet.h"
+
+int main(int argc, char** argv) {
+  if (argc != 3) {
+    fprintf(stderr, "Usage %s ./cap.0 ./cap.1\n", argv[0]);
+    exit(EXIT_FAILURE);
+  }
+  uint8_t verbose = 0;
+
+  FILE *fd[2]; size_t sz[2];
+  for (int i = 0; i < 2; i++) {
+    if ((fd[i] = fopen(argv[i+1], "r")) == NULL) {
+      perror("Unable to open file");
+      exit(EXIT_FAILURE);
+    }
+
+    fseek(fd[i], 0, SEEK_END);
+    sz[i] = ftell(fd[i]);
+    fseek(fd[i], 0, SEEK_SET);
+  }
+
+  if (sz[0] != sz[1]) {
+    printf("[!!] %s has %ld entries, %s has %ld entries\n",
+           argv[1],
+           sz[0]/sizeof(struct buffer_packet),
+           argv[2],
+           sz[1]/sizeof(struct buffer_packet));
+  } else if (verbose) {
+    printf("[OK] %s and %s have %ld entries\n",
+           argv[1],
+           argv[2],
+           sz[0]/sizeof(struct buffer_packet));
+  }
+
+  size_t to_read = sz[0] < sz[1] ? sz[0] : sz[1];
+  size_t to_read_obj = to_read / sizeof(struct buffer_packet);
+  uint16_t expected_id = 0;
+  struct buffer_packet bpread[2];
+  for (size_t c = 0; c < to_read_obj; c++) {
+    for (int i = 0; i < 2; i++) fread(&bpread[i], sizeof(struct buffer_packet), 1, fd[i]);
+    /*if (expected_id != bpread[0].ip.ap.fmt.content.clear.id || expected_id != bpread[1].ip.ap.fmt.content.clear.id) {
+      printf("[!!] expected id is %d, %s has id %d, %s has id %d\n",
+             expected_id,
+             argv[1],
+             bpread[0].ip.ap.fmt.content.clear.id,
+             argv[2],
+             bpread[1].ip.ap.fmt.content.clear.id);
+    }*/
+
+    uint8_t is_same_size = bpread[0].ip.ap.fmt.headers.size == bpread[1].ip.ap.fmt.headers.size;
+    if (!is_same_size) {
+      printf("[!!] %s packet has size %d, %s packet has size %d for expected id %d\n",
+             argv[1],
+             bpread[0].ip.ap.fmt.headers.size,
+             argv[2],
+             bpread[1].ip.ap.fmt.headers.size,
+             expected_id);
+    } else if (verbose) {
+      printf("[OK] %s and %s packets for expected id %d have size %d\n",
+             argv[1],
+             argv[2],
+             expected_id,
+             bpread[0].ip.ap.fmt.headers.size);
+    }
+
+    size_t s1 = bpread[0].ip.ap.fmt.headers.size, s2 = bpread[1].ip.ap.fmt.headers.size;
+    size_t max_size = s1 > s2 ? s1 : s2;
+    for (size_t idx = 0; idx < max_size; idx++) {
+      char e1 = (&bpread[0].ip.ap.raw)[idx], e2 = (&bpread[0].ip.ap.raw)[idx];
+      if (e1 != e2) {
+        printf("[!!] for expected id %d, byte 0x%04x is different: 0x%02x vs 0x%02x\n", expected_id, (uint16_t)idx, (uint8_t)e1, (uint8_t)e2);
+      }
+    }
+
+    expected_id++;
+  }
+
+
+  for (int i = 0; i < 2; i++) {
+    fclose(fd[i]);
+  }
+
+  printf("done\n");
+  return 0;
+}