MS-TURN support for Microsoft Office Communicator

agent/agent.c

@@ -169,7 +169,10 @@ agent_to_turn_compatibility (NiceAgent *agent)
       agent->compatibility == NICE_COMPATIBILITY_WLM2009 ?
       STUN_USAGE_TURN_COMPATIBILITY_MSN :
       agent->compatibility == NICE_COMPATIBILITY_OC2007 ?
-      STUN_USAGE_TURN_COMPATIBILITY_MSN : STUN_USAGE_TURN_COMPATIBILITY_DRAFT9;
+      STUN_USAGE_TURN_COMPATIBILITY_OC2007 :
+      agent->compatibility == NICE_COMPATIBILITY_OC2007R2 ?
+      STUN_USAGE_TURN_COMPATIBILITY_OC2007 :
+      STUN_USAGE_TURN_COMPATIBILITY_DRAFT9;
 }
 
 NiceTurnSocketCompatibility
@@ -182,7 +185,9 @@ agent_to_turn_socket_compatibility (NiceAgent *agent)
       agent->compatibility == NICE_COMPATIBILITY_WLM2009 ?
       NICE_TURN_SOCKET_COMPATIBILITY_MSN :
       agent->compatibility == NICE_COMPATIBILITY_OC2007 ?
-      NICE_TURN_SOCKET_COMPATIBILITY_MSN :
+      NICE_TURN_SOCKET_COMPATIBILITY_OC2007 :
+      agent->compatibility == NICE_COMPATIBILITY_OC2007R2 ?
+      NICE_TURN_SOCKET_COMPATIBILITY_OC2007 :
       NICE_TURN_SOCKET_COMPATIBILITY_DRAFT9;
 }
 
@@ -840,8 +845,7 @@ nice_agent_set_property (
             STUN_COMPATIBILITY_RFC3489,
             STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
             STUN_AGENT_USAGE_IGNORE_CREDENTIALS);
-      } else if (agent->compatibility == NICE_COMPATIBILITY_MSN ||
-		 agent->compatibility == NICE_COMPATIBILITY_OC2007) {
+      } else if (agent->compatibility == NICE_COMPATIBILITY_MSN) {
         stun_agent_init (&agent->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
             STUN_COMPATIBILITY_RFC3489,
             STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
@@ -851,11 +855,18 @@ nice_agent_set_property (
             STUN_COMPATIBILITY_WLM2009,
             STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
             STUN_AGENT_USAGE_USE_FINGERPRINT);
+      } else if (agent->compatibility == NICE_COMPATIBILITY_OC2007) {
+        stun_agent_init (&agent->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
+            STUN_COMPATIBILITY_RFC3489,
+            STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
+            STUN_AGENT_USAGE_FORCE_VALIDATER |
+            STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES);
       } else if (agent->compatibility == NICE_COMPATIBILITY_OC2007R2) {
         stun_agent_init (&agent->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
             STUN_COMPATIBILITY_WLM2009,
             STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
-            STUN_AGENT_USAGE_USE_FINGERPRINT);
+            STUN_AGENT_USAGE_USE_FINGERPRINT |
+            STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES);
       } else {
         stun_agent_init (&agent->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
             STUN_COMPATIBILITY_RFC5389,
@@ -1327,7 +1338,10 @@ priv_add_new_candidate_discovery_stun (NiceAgent *agent,
   cdisco->component = stream_find_component_by_id (stream, component_id);
   cdisco->agent = agent;
   stun_agent_init (&cdisco->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
-      STUN_COMPATIBILITY_RFC3489, 0);
+      STUN_COMPATIBILITY_RFC3489,
+      (agent->compatibility == NICE_COMPATIBILITY_OC2007 ||
+       agent->compatibility == NICE_COMPATIBILITY_OC2007R2) ?
+        STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES : 0);
 
   nice_debug ("Agent %p : Adding new srv-rflx candidate discovery %p\n",
       agent, cdisco);
@@ -1424,6 +1438,12 @@ priv_add_new_candidate_discovery_turn (NiceAgent *agent,
     stun_agent_init (&cdisco->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
         STUN_COMPATIBILITY_RFC3489,
         STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS);
+  } else if (agent->compatibility == NICE_COMPATIBILITY_OC2007 ||
+      agent->compatibility == NICE_COMPATIBILITY_OC2007R2) {
+    stun_agent_init (&cdisco->stun_agent, STUN_MSOC_KNOWN_ATTRIBUTES,
+        STUN_COMPATIBILITY_OC2007,
+        STUN_AGENT_USAGE_LONG_TERM_CREDENTIALS |
+        STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES);
   } else {
     stun_agent_init (&cdisco->stun_agent, STUN_ALL_KNOWN_ATTRIBUTES,
         STUN_COMPATIBILITY_RFC5389,
@@ -2210,7 +2230,9 @@ _nice_agent_recv (
 
   agent->media_after_tick = TRUE;
 
-  if (stun_message_validate_buffer_length ((uint8_t *) buf, (size_t) len) != len)
+  if (stun_message_validate_buffer_length ((uint8_t *) buf, (size_t) len,
+      (agent->compatibility != NICE_COMPATIBILITY_OC2007 &&
+       agent->compatibility != NICE_COMPATIBILITY_OC2007R2)) != len)
     /* If the retval is no 0, its not a valid stun packet, probably data */
     return len;
 

agent/conncheck.c

@@ -789,14 +789,16 @@ static void priv_turn_allocate_refresh_tick_unlocked (CandidateRefresh *cand)
   uint8_t *password;
   size_t password_len;
   size_t buffer_len = 0;
+  StunUsageTurnCompatibility turn_compat =
+      agent_to_turn_compatibility (cand->agent);
 
   username = (uint8_t *)cand->turn->username;
   username_len = (size_t) strlen (cand->turn->username);
   password = (uint8_t *)cand->turn->password;
   password_len = (size_t) strlen (cand->turn->password);
 
-  if (agent_to_turn_compatibility (cand->agent) ==
-      STUN_USAGE_TURN_COMPATIBILITY_MSN) {
+  if (turn_compat == STUN_USAGE_TURN_COMPATIBILITY_MSN ||
+      turn_compat == STUN_USAGE_TURN_COMPATIBILITY_OC2007) {
     username = g_base64_decode ((gchar *)username, &username_len);
     password = g_base64_decode ((gchar *)password, &password_len);
   }
@@ -806,10 +808,10 @@ static void priv_turn_allocate_refresh_tick_unlocked (CandidateRefresh *cand)
       cand->stun_resp_msg.buffer == NULL ? NULL : &cand->stun_resp_msg, -1,
       username, username_len,
       password, password_len,
-      agent_to_turn_compatibility (cand->agent));
+      turn_compat);
 
-  if (agent_to_turn_compatibility (cand->agent) ==
-      STUN_USAGE_TURN_COMPATIBILITY_MSN) {
+  if (turn_compat == STUN_USAGE_TURN_COMPATIBILITY_MSN ||
+      turn_compat == STUN_USAGE_TURN_COMPATIBILITY_OC2007) {
     g_free (cand->msn_turn_username);
     g_free (cand->msn_turn_password);
     cand->msn_turn_username = username;
@@ -2331,6 +2333,11 @@ static gboolean priv_map_reply_to_relay_request (NiceAgent *agent, StunMessage *
 
           if (relay_cand) {
             priv_add_new_turn_refresh (d, relay_cand, lifetime);
+            if (agent->compatibility == NICE_COMPATIBILITY_OC2007 ||
+                agent->compatibility == NICE_COMPATIBILITY_OC2007R2) {
+                  nice_turn_socket_set_ms_realm(relay_cand->sockptr, &d->stun_message);
+                  nice_turn_socket_set_ms_connection_id(relay_cand->sockptr, resp);
+            }
           }
 
           d->stun_message.buffer = NULL;
@@ -2350,7 +2357,9 @@ static gboolean priv_map_reply_to_relay_request (NiceAgent *agent, StunMessage *
               STUN_ATTRIBUTE_REALM, &recv_realm_len);
 
           /* check for unauthorized error response */
-          if (agent->compatibility == NICE_COMPATIBILITY_RFC5245 &&
+          if ((agent->compatibility == NICE_COMPATIBILITY_RFC5245 ||
+               agent->compatibility == NICE_COMPATIBILITY_OC2007  ||
+               agent->compatibility == NICE_COMPATIBILITY_OC2007R2) &&
               stun_message_get_class (resp) == STUN_ERROR &&
               stun_message_find_error (resp, &code) ==
               STUN_MESSAGE_RETURN_SUCCESS &&

agent/discovery.c

@@ -141,6 +141,7 @@ void refresh_free_item (gpointer data, gpointer user_data)
   uint8_t *password;
   size_t password_len;
   size_t buffer_len = 0;
+  StunUsageTurnCompatibility turn_compat = agent_to_turn_compatibility (agent);
 
   g_assert (user_data == NULL);
 
@@ -160,7 +161,8 @@ void refresh_free_item (gpointer data, gpointer user_data)
   password = (uint8_t *)cand->turn->password;
   password_len = (size_t) strlen (cand->turn->password);
 
-  if (agent_to_turn_compatibility (agent) == STUN_USAGE_TURN_COMPATIBILITY_MSN) {
+  if (turn_compat == STUN_USAGE_TURN_COMPATIBILITY_MSN ||
+      turn_compat == STUN_USAGE_TURN_COMPATIBILITY_OC2007) {
     username = g_base64_decode ((gchar *)username, &username_len);
     password = g_base64_decode ((gchar *)password, &password_len);
   }
@@ -188,7 +190,8 @@ void refresh_free_item (gpointer data, gpointer user_data)
 
   }
 
-  if (agent_to_turn_compatibility (agent) == STUN_USAGE_TURN_COMPATIBILITY_MSN) {
+  if (turn_compat == STUN_USAGE_TURN_COMPATIBILITY_MSN ||
+      turn_compat == STUN_USAGE_TURN_COMPATIBILITY_OC2007) {
     g_free (username);
     g_free (password);
   }
@@ -868,9 +871,11 @@ static gboolean priv_discovery_tick_unlocked (gpointer pointer)
           size_t username_len = (size_t) strlen (cand->turn->username);
           uint8_t *password = (uint8_t *)cand->turn->password;
           size_t password_len = (size_t) strlen (cand->turn->password);
+          StunUsageTurnCompatibility turn_compat =
+              agent_to_turn_compatibility (agent);
 
-          if (agent_to_turn_compatibility (agent) ==
-              STUN_USAGE_TURN_COMPATIBILITY_MSN) {
+          if (turn_compat == STUN_USAGE_TURN_COMPATIBILITY_MSN ||
+              turn_compat == STUN_USAGE_TURN_COMPATIBILITY_OC2007) {
             username = g_base64_decode ((gchar *)username, &username_len);
             password = g_base64_decode ((gchar *)password, &password_len);
           }
@@ -882,10 +887,10 @@ static gboolean priv_discovery_tick_unlocked (gpointer pointer)
               -1, -1,
               username, username_len,
               password, password_len,
-              agent_to_turn_compatibility (agent));
+              turn_compat);
 
-          if (agent_to_turn_compatibility (agent) ==
-              STUN_USAGE_TURN_COMPATIBILITY_MSN) {
+          if (turn_compat == STUN_USAGE_TURN_COMPATIBILITY_MSN ||
+              turn_compat == STUN_USAGE_TURN_COMPATIBILITY_OC2007) {
             g_free (cand->msn_turn_username);
             g_free (cand->msn_turn_password);
             cand->msn_turn_username = username;

socket/turn.c

@@ -51,6 +51,7 @@
 #include "agent-priv.h"
 
 #define STUN_END_TIMEOUT 8000
+#define STUN_MAX_MS_REALM_LEN 128 // as defined in [MS-TURN]
 
 
 typedef struct {
@@ -80,6 +81,10 @@ typedef struct {
   size_t password_len;
   NiceTurnSocketCompatibility compatibility;
   GQueue *send_requests;
+  uint8_t ms_realm[STUN_MAX_MS_REALM_LEN + 1];
+  uint8_t ms_connection_id[20];
+  uint32_t ms_sequence_num;
+  bool ms_connection_id_valid;
 } TurnPriv;
 
 
@@ -133,6 +138,13 @@ nice_turn_socket_new (NiceAgent *agent, NiceAddress *addr,
         STUN_COMPATIBILITY_RFC3489,
         STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
         STUN_AGENT_USAGE_IGNORE_CREDENTIALS);
+  } else if (compatibility == NICE_TURN_SOCKET_COMPATIBILITY_OC2007) {
+      stun_agent_init (&priv->agent, STUN_ALL_KNOWN_ATTRIBUTES,
+        STUN_COMPATIBILITY_OC2007,
+        STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS |
+        STUN_AGENT_USAGE_NO_INDICATION_AUTH |
+        STUN_AGENT_USAGE_LONG_TERM_CREDENTIALS |
+        STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES);
   }
 
   priv->nice = agent;
@@ -140,7 +152,8 @@ nice_turn_socket_new (NiceAgent *agent, NiceAddress *addr,
   priv->current_binding = NULL;
   priv->base_socket = base_socket;
 
-  if (compatibility == NICE_TURN_SOCKET_COMPATIBILITY_MSN) {
+  if (compatibility == NICE_TURN_SOCKET_COMPATIBILITY_MSN ||
+      compatibility == NICE_TURN_SOCKET_COMPATIBILITY_OC2007) {
     priv->username = g_base64_decode (username, &priv->username_len);
     priv->password = g_base64_decode (password, &priv->password_len);
   } else {
@@ -230,6 +243,33 @@ socket_recv (NiceSocket *sock, NiceAddress *from, guint len, gchar *buf)
     return recv_len;
 }
 
+static StunMessageReturn
+stun_message_append_ms_connection_id(StunMessage *msg,
+    uint8_t *ms_connection_id, uint32_t ms_sequence_num)
+{
+  uint8_t buf[24];
+
+  memcpy(buf, ms_connection_id, 20);
+  *(uint32_t*)(buf + 20) = htonl(ms_sequence_num);
+  return stun_message_append_bytes (msg, STUN_ATTRIBUTE_MS_SEQUENCE_NUMBER,
+                                    buf, 24);
+}
+
+static void
+stun_message_ensure_ms_realm(StunMessage *msg, uint8_t *realm)
+{
+  /* With MS-TURN, original clients do not send REALM attribute in Send and Set
+   * Active Destination requests, but use it to compute MESSAGE-INTEGRITY. We
+   * simply append cached realm value to the message and use it in subsequent
+   * stun_agent_finish_message() call. Messages with this additional attribute
+   * are handled correctly on OCS Access Edge working as TURN server. */
+  if (stun_message_get_method(msg) == STUN_SEND ||
+      stun_message_get_method(msg) == STUN_OLD_SET_ACTIVE_DST) {
+    stun_message_append_bytes (msg, STUN_ATTRIBUTE_REALM, realm,
+                               strlen((char *)realm));
+  }
+}
+
 static gboolean
 socket_send (NiceSocket *sock, const NiceAddress *to,
     guint len, const gchar *buf)
@@ -301,6 +341,16 @@ socket_send (NiceSocket *sock, const NiceAddress *to,
       }
     }
 
+    if (priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_OC2007) {
+      stun_message_append32(&msg, STUN_ATTRIBUTE_MS_VERSION, 1);
+
+      if (priv->ms_connection_id_valid)
+        stun_message_append_ms_connection_id(&msg, priv->ms_connection_id,
+            ++priv->ms_sequence_num);
+
+      stun_message_ensure_ms_realm(&msg, priv->ms_realm);
+    }
+
     if (stun_message_append_bytes (&msg, STUN_ATTRIBUTE_DATA,
             buf, len) != STUN_MESSAGE_RETURN_SUCCESS)
       goto send;
@@ -436,7 +486,8 @@ nice_turn_socket_parse_recv (NiceSocket *sock, NiceSocket **from_sock,
             priv->current_binding_msg = NULL;
 
             if (stun_message_get_class (&msg) == STUN_RESPONSE &&
-                priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_MSN) {
+                (priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_MSN ||
+                 priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_OC2007)) {
               goto msn_google_lock;
             } else {
               g_free (priv->current_binding);
@@ -817,7 +868,8 @@ priv_add_channel_binding (TurnPriv *priv, NiceAddress *peer)
       return ret;
     }
     return FALSE;
-  } else if (priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_MSN) {
+  } else if (priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_MSN ||
+             priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_OC2007) {
     TURNMessage *msg = g_new0 (TURNMessage, 1);
     if (!stun_agent_init_request (&priv->agent, &msg->message,
             msg->buffer, sizeof(msg->buffer), STUN_OLD_SET_ACTIVE_DST)) {
@@ -839,6 +891,14 @@ priv_add_channel_binding (TurnPriv *priv, NiceAddress *peer)
       }
     }
 
+    if (priv->compatibility == NICE_TURN_SOCKET_COMPATIBILITY_OC2007) {
+      if (priv->ms_connection_id_valid)
+          stun_message_append_ms_connection_id(&msg->message,
+              priv->ms_connection_id, ++priv->ms_sequence_num);
+
+      stun_message_ensure_ms_realm(&msg->message, priv->ms_realm);
+    }
+
     if (stun_message_append_addr (&msg->message,
             STUN_ATTRIBUTE_DESTINATION_ADDRESS,
             (struct sockaddr *)&sa, sizeof(sa)) != STUN_MESSAGE_RETURN_SUCCESS) {
@@ -869,3 +929,31 @@ priv_add_channel_binding (TurnPriv *priv, NiceAddress *peer)
 
   return FALSE;
 }
+
+void
+nice_turn_socket_set_ms_realm(NiceSocket *sock, StunMessage *msg)
+{
+  TurnPriv *priv = (TurnPriv *)sock->priv;
+  uint16_t alen;
+  const uint8_t *realm = stun_message_find(msg, STUN_ATTRIBUTE_REALM, &alen);
+
+  if (realm && alen <= STUN_MAX_MS_REALM_LEN) {
+    memcpy(priv->ms_realm, realm, alen);
+    priv->ms_realm[alen] = '\0';
+  }
+}
+
+void
+nice_turn_socket_set_ms_connection_id (NiceSocket *sock, StunMessage *msg)
+{
+  TurnPriv *priv = (TurnPriv *)sock->priv;
+  uint16_t alen;
+  const uint8_t *ms_seq_num = stun_message_find(msg,
+      STUN_ATTRIBUTE_MS_SEQUENCE_NUMBER, &alen);
+
+  if (ms_seq_num && alen == 24) {
+      memcpy (priv->ms_connection_id, ms_seq_num, 20);
+      priv->ms_sequence_num = ntohl((uint32_t)*(ms_seq_num + 20));
+      priv->ms_connection_id_valid = TRUE;
+  }
+}

socket/turn.h

@@ -42,10 +42,12 @@ typedef enum {
   NICE_TURN_SOCKET_COMPATIBILITY_DRAFT9,
   NICE_TURN_SOCKET_COMPATIBILITY_GOOGLE,
   NICE_TURN_SOCKET_COMPATIBILITY_MSN,
+  NICE_TURN_SOCKET_COMPATIBILITY_OC2007,
 } NiceTurnSocketCompatibility;
 
 #include "socket.h"
 #include "agent.h"
+#include "stun/stunmessage.h"
 
 
 G_BEGIN_DECLS
@@ -63,6 +65,12 @@ nice_turn_socket_new (NiceAgent *agent, NiceAddress *addr,
     NiceSocket *base_socket, NiceAddress *server_addr,
     gchar *username, gchar *password, NiceTurnSocketCompatibility compatibility);
 
+void
+nice_turn_socket_set_ms_realm(NiceSocket *sock, StunMessage *msg);
+
+void
+nice_turn_socket_set_ms_connection_id (NiceSocket *sock, StunMessage *msg);
+
 
 G_END_DECLS
 

stun/stunagent.c

@@ -117,7 +117,8 @@ StunValidationStatus stun_agent_validate (StunAgent *agent, StunMessage *msg,
   uint8_t long_term_key[16];
   bool long_term_key_valid = FALSE;
 
-  len = stun_message_validate_buffer_length (buffer, buffer_len);
+  len = stun_message_validate_buffer_length (buffer, buffer_len,
+       !(agent->usage_flags & STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES));
   if (len == STUN_MESSAGE_BUFFER_INVALID) {
     return STUN_VALIDATION_NOT_STUN;
   } else if (len == STUN_MESSAGE_BUFFER_INCOMPLETE) {
@@ -257,7 +258,8 @@ StunValidationStatus stun_agent_validate (StunAgent *agent, StunMessage *msg,
         memcpy (msg->long_term_key, md5, sizeof(md5));
         msg->long_term_valid = TRUE;
 
-        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489) {
+        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489 ||
+            agent->compatibility == STUN_COMPATIBILITY_OC2007) {
           stun_sha1 (msg->buffer, hash + 20 - msg->buffer, hash - msg->buffer,
               sha, md5, sizeof(md5), TRUE);
         } else if (agent->compatibility == STUN_COMPATIBILITY_WLM2009) {
@@ -268,7 +270,8 @@ StunValidationStatus stun_agent_validate (StunAgent *agent, StunMessage *msg,
               hash - msg->buffer, sha, md5, sizeof(md5), FALSE);
         }
       } else {
-        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489) {
+        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489 ||
+            agent->compatibility == STUN_COMPATIBILITY_OC2007) {
           stun_sha1 (msg->buffer, hash + 20 - msg->buffer, hash - msg->buffer,
               sha, key, key_len, TRUE);
         } else if (agent->compatibility == STUN_COMPATIBILITY_WLM2009) {
@@ -564,7 +567,8 @@ size_t stun_agent_finish_message (StunAgent *agent, StunMessage *msg,
         return 0;
       }
       if (agent->usage_flags & STUN_AGENT_USAGE_LONG_TERM_CREDENTIALS) {
-        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489) {
+        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489 ||
+            agent->compatibility == STUN_COMPATIBILITY_OC2007) {
           stun_sha1 (msg->buffer, stun_message_length (msg),
               stun_message_length (msg) - 20, ptr, md5, sizeof(md5), TRUE);
         } else if (agent->compatibility == STUN_COMPATIBILITY_WLM2009) {
@@ -579,7 +583,8 @@ size_t stun_agent_finish_message (StunAgent *agent, StunMessage *msg,
               stun_message_length (msg) - 20, ptr, md5, sizeof(md5), FALSE);
         }
       } else {
-        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489) {
+        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489 ||
+            agent->compatibility == STUN_COMPATIBILITY_OC2007) {
           stun_sha1 (msg->buffer, stun_message_length (msg),
               stun_message_length (msg) - 20, ptr, key, key_len, TRUE);
         } else if (agent->compatibility == STUN_COMPATIBILITY_WLM2009) {
@@ -671,14 +676,17 @@ stun_agent_find_unknowns (StunAgent *agent, const StunMessage * msg,
     size_t alen = stun_getw (msg->buffer + offset + STUN_ATTRIBUTE_TYPE_LEN);
     uint16_t atype = stun_getw (msg->buffer + offset);
 
-    offset += STUN_ATTRIBUTE_VALUE_POS + stun_align (alen);
-
     if (!stun_optional (atype) && stun_agent_is_unknown (agent, atype))
     {
       stun_debug ("STUN unknown: attribute 0x%04x(%u bytes)\n",
            (unsigned)atype, (unsigned)alen);
       list[count++] = htons (atype);
     }
+
+    if (!(agent->usage_flags & STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES))
+      alen = stun_align (alen);
+
+    offset += STUN_ATTRIBUTE_VALUE_POS + alen;
   }
 
   stun_debug ("STUN unknown: %u mandatory attribute(s)!\n", count);

stun/stunagent.h

@@ -82,6 +82,9 @@ typedef struct stun_agent_t StunAgent;
  * @STUN_COMPATIBILITY_WLM2009: Use the STUN specifications compatible with
  * Windows Live Messenger 2009 (a mix between RFC3489 and RFC5389, as well as
  * a special usecase against a typo in their code)
+ * @STUN_COMPATIBILITY_OC2007: Use the STUN specifications compatible with
+ * Microsoft Office Communicator 2007 (basically RFC3489 with swapped
+ * REALM and NONCE attribute hex IDs, attributes are not aligned)
  * @STUN_COMPATIBILITY_LAST: Dummy last compatibility mode
  *
  * Enum that specifies the STUN compatibility mode of the #StunAgent
@@ -90,7 +93,8 @@ typedef enum {
   STUN_COMPATIBILITY_RFC3489,
   STUN_COMPATIBILITY_RFC5389,
   STUN_COMPATIBILITY_WLM2009,
-  STUN_COMPATIBILITY_LAST = STUN_COMPATIBILITY_WLM2009
+  STUN_COMPATIBILITY_OC2007,
+  STUN_COMPATIBILITY_LAST = STUN_COMPATIBILITY_OC2007
 } StunCompatibility;
 
 
@@ -157,6 +161,9 @@ typedef enum {
  * should be (a response to a previously created request). This means that the
  * #StunMessageIntegrityValidate callback will always be called when there is
  * a MESSAGE-INTEGRITY attribute.
+ * @STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES: The agent should not assume STUN
+ * attributes are aligned on 32-bit boundaries when parsing messages and also
+ * do not add padding when creating messages.
  *
  * This enum defines a bitflag usages for a #StunAgent and they will define how
  * the agent should behave, independently of the compatibility mode it uses.
@@ -171,6 +178,7 @@ typedef enum {
   STUN_AGENT_USAGE_IGNORE_CREDENTIALS        = (1 << 4),
   STUN_AGENT_USAGE_NO_INDICATION_AUTH        = (1 << 5),
   STUN_AGENT_USAGE_FORCE_VALIDATER           = (1 << 6),
+  STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES     = (1 << 7),
 } StunAgentUsageFlags;
 
 

stun/stunmessage.c

@@ -88,6 +88,14 @@ stun_message_find (const StunMessage *msg, StunAttribute type,
   size_t length = stun_message_length (msg);
   size_t offset = 0;
 
+  /* In MS-TURN, IDs of REALM and NONCE STUN attributes are swapped. */
+  if (msg->agent && msg->agent->compatibility == STUN_COMPATIBILITY_OC2007)
+  {
+    if (type == STUN_ATTRIBUTE_REALM)
+      type = STUN_ATTRIBUTE_NONCE;
+    else if (type == STUN_ATTRIBUTE_NONCE)
+      type = STUN_ATTRIBUTE_REALM;
+  }
 
   offset = STUN_MESSAGE_ATTRIBUTES_POS;
 
@@ -118,7 +126,9 @@ stun_message_find (const StunMessage *msg, StunAttribute type,
         return NULL;
     }
 
-    alen = stun_align (alen);
+    if (!(msg->agent->usage_flags & STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES))
+      alen = stun_align (alen);
+
     offset += alen;
   }
 
@@ -317,20 +327,35 @@ stun_message_append (StunMessage *msg, StunAttribute type, size_t length)
   uint8_t *a;
   uint16_t mlen = stun_message_length (msg);
 
+  /* In MS-TURN, IDs of REALM and NONCE STUN attributes are swapped. */
+  if (msg->agent && msg->agent->compatibility == STUN_COMPATIBILITY_OC2007)
+  {
+    if (type == STUN_ATTRIBUTE_NONCE)
+      type = STUN_ATTRIBUTE_REALM;
+    else if (type == STUN_ATTRIBUTE_REALM)
+      type = STUN_ATTRIBUTE_NONCE;
+  }
+
   if ((size_t)mlen + STUN_ATTRIBUTE_HEADER_LENGTH + length > msg->buffer_len)
     return NULL;
 
 
   a = msg->buffer + mlen;
   a = stun_setw (a, type);
-  /* NOTE: If cookie is not present, we need to force the attribute length
-   * to a multiple of 4 for compatibility with old RFC3489 */
-  a = stun_setw (a, stun_message_has_cookie (msg) ? length : stun_align (length));
+  if (msg->agent->usage_flags & STUN_AGENT_USAGE_NO_ALIGNED_ATTRIBUTES)
+  {
+    a = stun_setw (a, length);
+  } else {
+    /* NOTE: If cookie is not present, we need to force the attribute length
+     * to a multiple of 4 for compatibility with old RFC3489 */
+    a = stun_setw (a, stun_message_has_cookie (msg) ? length : stun_align (length));
+
+    /* Add padding if needed */
+    memset (a + length, ' ', stun_padding (length));
+    mlen += stun_padding (length);
+  }
 
   mlen +=  4 + length;
-  /* Add padding if needed */
-  memset (a + length, ' ', stun_padding (length));
-  mlen += stun_padding (length);
 
   stun_setw (msg->buffer + STUN_MESSAGE_LENGTH_POS, mlen - STUN_MESSAGE_HEADER_LENGTH);
   return a;
@@ -499,7 +524,8 @@ stun_message_append_error (StunMessage *msg, StunError code)
   return STUN_MESSAGE_RETURN_SUCCESS;
 }
 
-int stun_message_validate_buffer_length (const uint8_t *msg, size_t length)
+int stun_message_validate_buffer_length (const uint8_t *msg, size_t length,
+    bool has_padding)
 {
   size_t mlen;
   size_t len;
@@ -525,7 +551,7 @@ int stun_message_validate_buffer_length (const uint8_t *msg, size_t length)
   mlen = stun_getw (msg + STUN_MESSAGE_LENGTH_POS) +
       STUN_MESSAGE_HEADER_LENGTH;
 
-  if (stun_padding (mlen))
+  if (has_padding && stun_padding (mlen))
   {
     stun_debug ("STUN error: Invalid message length: %u!\n", (unsigned)mlen);
     return STUN_MESSAGE_BUFFER_INVALID; // wrong padding
@@ -544,7 +570,9 @@ int stun_message_validate_buffer_length (const uint8_t *msg, size_t length)
   /* from then on, we know we have the entire packet in buffer */
   while (len > 0)
   {
-    size_t alen = stun_align (stun_getw (msg + STUN_ATTRIBUTE_TYPE_LEN));
+    size_t alen = stun_getw (msg + STUN_ATTRIBUTE_TYPE_LEN);
+    if (has_padding)
+      alen = stun_align (alen);
 
     /* thanks to padding check, if (end > msg) then there is not only one
      * but at least 4 bytes left */

stun/stunmessage.h

@@ -209,6 +209,8 @@ typedef enum
  * ICE draft 19
  * @STUN_ATTRIBUTE_OPTIONS: The OPTIONS optional attribute as defined by
  * libjingle
+ * @STUN_ATTRIBUTE_MS_VERSION: The MS-VERSION optional attribute as defined
+ * by [MS-TURN]
  * @STUN_ATTRIBUTE_SOFTWARE: The SOFTWARE optional attribute as defined by RFC5389
  * @STUN_ATTRIBUTE_ALTERNATE_SERVER: The ALTERNATE-SERVER optional attribute as
  * defined by RFC5389
@@ -218,6 +220,8 @@ typedef enum
  * defined by ICE draft 19
  * @STUN_ATTRIBUTE_ICE_CONTROLLING: The ICE-CONTROLLING optional attribute as
  * defined by ICE draft 19
+ * @STUN_ATTRIBUTE_MS_SEQUENCE_NUMBER: The MS-SEQUENCE NUMBER optional attribute
+ * as defined by [MS-TURN]
  * @STUN_ATTRIBUTE_CANDIDATE_IDENTIFIER: The CANDIDATE-IDENTIFIER optional
  * attribute as defined by [MS-ICE2]
  *
@@ -241,7 +245,9 @@ typedef enum
   STUN_ATTRIBUTE_REFLECTED_FROM=0x000B,    /* old RFC3489 */
   STUN_ATTRIBUTE_CHANNEL_NUMBER=0x000C,        /* TURN-12 */
   STUN_ATTRIBUTE_LIFETIME=0x000D,      /* TURN-12 */
-  /* 0x000E */        /* reserved (was ALTERNATE-SERVER from midcom-TURN 08 */
+  /* MS_ALTERNATE_SERVER is only used by Microsoft's dialect, probably should
+   * not to be placed in STUN_ALL_KNOWN_ATTRIBUTES */
+  STUN_ATTRIBUTE_MS_ALTERNATE_SERVER=0x000E, /* MS-TURN */
   STUN_ATTRIBUTE_MAGIC_COOKIE=0x000F,        /* midcom-TURN 08 */
   STUN_ATTRIBUTE_BANDWIDTH=0x0010,      /* TURN-04 */
   STUN_ATTRIBUTE_DESTINATION_ADDRESS=0x0011,        /* midcom-TURN 08 */
@@ -281,6 +287,7 @@ typedef enum
   /* Optional attributes */
   /* 0x8000-0x8021 */      /* reserved */
   STUN_ATTRIBUTE_OPTIONS=0x8001, /* libjingle */
+  STUN_ATTRIBUTE_MS_VERSION=0x8008,    /* MS-TURN */
   STUN_ATTRIBUTE_SOFTWARE=0x8022,      /* RFC5389 */
   STUN_ATTRIBUTE_ALTERNATE_SERVER=0x8023,    /* RFC5389 */
   /* 0x8024 */        /* reserved */
@@ -290,7 +297,9 @@ typedef enum
   STUN_ATTRIBUTE_FINGERPRINT=0x8028,    /* RFC5389 */
   STUN_ATTRIBUTE_ICE_CONTROLLED=0x8029,    /* ICE-19 */
   STUN_ATTRIBUTE_ICE_CONTROLLING=0x802A,    /* ICE-19 */
-  /* 0x802B-0x8053 */      /* reserved */
+  /* 0x802B-0x804F */      /* reserved */
+  STUN_ATTRIBUTE_MS_SEQUENCE_NUMBER=0x8050,     /* MS-TURN */
+  /* 0x8051-0x8053 */      /* reserved */
   STUN_ATTRIBUTE_CANDIDATE_IDENTIFIER=0x8054    /* MS-ICE2 */
   /* 0x8055-0xFFFF */      /* reserved */
 } StunAttribute;
@@ -346,6 +355,36 @@ static const uint16_t STUN_ALL_KNOWN_ATTRIBUTES[] =
     0