Added preliminary Symbian support.
[silc.git] / lib / silccore / silcpacket.c
index adce3221a4cc5473a9fa2c30caeee1856772f653..6de9eb089a91860680de499226a1a3189e2077bd 100644 (file)
 
 /************************** Types and definitions ***************************/
 
+/* Per scheduler (which usually means per thread) data.  We put per scheduler
+   data here for accessing without locking.  SILC Schedule dictates that
+   tasks are dispatched in one thread, hence the per scheduler context. */
+typedef struct {
+  SilcSchedule schedule;                /* The scheduler */
+  SilcPacketEngine engine;              /* Packet engine */
+  SilcBufferStruct inbuf;               /* Data input buffer */
+  SilcUInt32 stream_count;              /* Number of streams using this */
+} *SilcPacketEngineContext;
+
 /* Packet engine */
 struct SilcPacketEngineStruct {
+  SilcMutex lock;                       /* Engine lock */
   SilcRng rng;                          /* RNG for engine */
+  SilcHashTable contexts;               /* Per scheduler contexts */
   SilcPacketCallbacks *callbacks;       /* Packet callbacks */
   void *callback_context;               /* Context for callbacks */
   SilcList streams;                     /* All streams in engine */
   SilcList packet_pool;                 /* Free list for received packets */
-  SilcMutex lock;                       /* Engine lock */
   SilcHashTable udp_remote;             /* UDP remote streams, or NULL */
-  SilcBool local_is_router;
+  unsigned int local_is_router    : 1;
 };
 
 /* Packet processor context */
 typedef struct SilcPacketProcessStruct {
-  SilcInt32 priority;                   /* Priority */
   SilcPacketType *types;                /* Packets to process */
   SilcPacketCallbacks *callbacks;       /* Callbacks or NULL */
   void *callback_context;
+  SilcInt32 priority;                   /* Priority */
 } *SilcPacketProcess;
 
 /* UDP remote stream tuple */
@@ -54,13 +65,12 @@ typedef struct {
 /* Packet stream */
 struct SilcPacketStreamStruct {
   struct SilcPacketStreamStruct *next;
-  SilcPacketEngine engine;              /* Packet engine */
+  SilcPacketEngineContext sc;           /* Per scheduler context */
   SilcStream stream;                    /* Underlaying stream */
   SilcMutex lock;                       /* Stream lock */
   SilcDList process;                    /* Packet processors, or NULL */
   SilcPacketRemoteUDP remote_udp;       /* UDP remote stream tuple, or NULL */
   void *stream_context;                         /* Stream context */
-  SilcBufferStruct inbuf;               /* In buffer */
   SilcBufferStruct outbuf;              /* Out buffer */
   SilcCipher send_key[2];               /* Sending key */
   SilcHmac send_hmac[2];                /* Sending HMAC */
@@ -138,21 +148,34 @@ do {                                                                         \
 /* EOS callback */
 #define SILC_PACKET_CALLBACK_EOS(s)                                    \
 do {                                                                   \
-  (s)->engine->callbacks->eos((s)->engine, s,                          \
-                             (s)->engine->callback_context,            \
-                             (s)->stream_context);                     \
+  (s)->sc->engine->callbacks->eos((s)->sc->engine, s,                  \
+                                 (s)->sc->engine->callback_context,    \
+                                 (s)->stream_context);                 \
 } while(0)
 
 /* Error callback */
 #define SILC_PACKET_CALLBACK_ERROR(s, err)                             \
 do {                                                                   \
-  (s)->engine->callbacks->error((s)->engine, s, err,                   \
-                               (s)->engine->callback_context,          \
-                               (s)->stream_context);                   \
+  (s)->sc->engine->callbacks->error((s)->sc->engine, s, err,           \
+                                   (s)->sc->engine->callback_context,  \
+                                   (s)->stream_context);               \
 } while(0)
 
-static void silc_packet_dispatch(SilcPacket packet);
+static SilcBool silc_packet_dispatch(SilcPacket packet);
 static void silc_packet_read_process(SilcPacketStream stream);
+static inline SilcBool silc_packet_send_raw(SilcPacketStream stream,
+                                           SilcPacketType type,
+                                           SilcPacketFlags flags,
+                                           SilcIdType src_id_type,
+                                           unsigned char *src_id,
+                                           SilcUInt32 src_id_len,
+                                           SilcIdType dst_id_type,
+                                           unsigned char *dst_id,
+                                           SilcUInt32 dst_id_len,
+                                           const unsigned char *data,
+                                           SilcUInt32 data_len,
+                                           SilcCipher cipher,
+                                           SilcHmac hmac);
 
 /************************ Static utility functions **************************/
 
@@ -166,14 +189,18 @@ SILC_TASK_CALLBACK(silc_packet_stream_inject_packet)
   SILC_LOG_DEBUG(("Injecting packet %p to stream %p", packet, packet->stream));
 
   silc_mutex_lock(stream->lock);
-  silc_packet_dispatch(packet);
+  if (!stream->destroyed)
+    silc_packet_dispatch(packet);
   silc_mutex_unlock(stream->lock);
+  silc_packet_stream_unref(stream);
 }
 
 /* Write data to the stream.  Must be called with ps->lock locked.  Unlocks
-   the lock inside this function. */
+   the lock inside this function, unless no_unlock is TRUE.  Unlocks always
+   in case it returns FALSE. */
 
-static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
+static inline SilcBool silc_packet_stream_write(SilcPacketStream ps,
+                                               SilcBool no_unlock)
 {
   SilcStream stream;
   SilcBool connected;
@@ -191,17 +218,17 @@ static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
        i = silc_net_udp_send(stream, ps->remote_udp->remote_ip,
                              ps->remote_udp->remote_port,
                              ps->outbuf.data, silc_buffer_len(&ps->outbuf));
-       if (i == -2) {
+       if (silc_unlikely(i == -2)) {
          /* Error */
          silc_buffer_reset(&ps->outbuf);
-         silc_mutex_unlock(ps->lock);
          SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_WRITE);
          return FALSE;
        }
 
-       if (i == -1) {
+       if (silc_unlikely(i == -1)) {
          /* Cannot write now, write later. */
-         silc_mutex_unlock(ps->lock);
+         if (!no_unlock)
+           silc_mutex_unlock(ps->lock);
          return TRUE;
        }
 
@@ -210,7 +237,8 @@ static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
       }
 
       silc_buffer_reset(&ps->outbuf);
-      silc_mutex_unlock(ps->lock);
+      if (!no_unlock)
+       silc_mutex_unlock(ps->lock);
 
       return TRUE;
     }
@@ -220,7 +248,7 @@ static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
   while (silc_buffer_len(&ps->outbuf) > 0) {
     i = silc_stream_write(stream, ps->outbuf.data,
                          silc_buffer_len(&ps->outbuf));
-    if (i == 0) {
+    if (silc_unlikely(i == 0)) {
       /* EOS */
       silc_buffer_reset(&ps->outbuf);
       silc_mutex_unlock(ps->lock);
@@ -228,7 +256,7 @@ static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
       return FALSE;
     }
 
-    if (i == -2) {
+    if (silc_unlikely(i == -2)) {
       /* Error */
       silc_buffer_reset(&ps->outbuf);
       silc_mutex_unlock(ps->lock);
@@ -236,9 +264,10 @@ static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
       return FALSE;
     }
 
-    if (i == -1) {
+    if (silc_unlikely(i == -1)) {
       /* Cannot write now, write later. */
-      silc_mutex_unlock(ps->lock);
+      if (!no_unlock)
+       silc_mutex_unlock(ps->lock);
       return TRUE;
     }
 
@@ -247,12 +276,13 @@ static inline SilcBool silc_packet_stream_write(SilcPacketStream ps)
   }
 
   silc_buffer_reset(&ps->outbuf);
-  silc_mutex_unlock(ps->lock);
+  if (!no_unlock)
+    silc_mutex_unlock(ps->lock);
 
   return TRUE;
 }
 
-/* Reads data from stream.  Must be called with the ps->lock locked.  If this
+/* Reads data from stream.  Must be called with ps->lock locked.  If this
    returns FALSE the lock has been unlocked.  If this returns packet stream
    to `ret_ps' its lock has been acquired and `ps' lock has been unlocked.
    It is returned if the stream is UDP and remote UDP stream exists for
@@ -262,19 +292,12 @@ static inline SilcBool silc_packet_stream_read(SilcPacketStream ps,
                                               SilcPacketStream *ret_ps)
 {
   SilcStream stream;
+  SilcBuffer inbuf;
   SilcBool connected;
   int ret;
 
   stream = ps->stream;
-
-  /* Make sure we have fair amount of free space in inbuf */
-  if (silc_buffer_taillen(&ps->inbuf) < SILC_PACKET_DEFAULT_SIZE)
-    if (!silc_buffer_realloc(&ps->inbuf, silc_buffer_truelen(&ps->inbuf) +
-                            SILC_PACKET_DEFAULT_SIZE * 2)) {
-      silc_mutex_unlock(ps->lock);
-      SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_NO_MEMORY);
-      return FALSE;
-    }
+  inbuf = &ps->sc->inbuf;
 
   if (silc_socket_stream_is_udp(stream, &connected)) {
     if (!connected) {
@@ -284,57 +307,42 @@ static inline SilcBool silc_packet_stream_read(SilcPacketStream ps,
       SilcPacketStream remote;
 
       ret = silc_net_udp_receive(stream, remote_ip, sizeof(remote_ip),
-                                &remote_port, ps->inbuf.tail,
-                                silc_buffer_taillen(&ps->inbuf));
-      if (ret == -2) {
-       /* Error */
-       silc_buffer_reset(&ps->inbuf);
-       silc_mutex_unlock(ps->lock);
-       SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_READ);
-       return FALSE;
-      }
+                                &remote_port, inbuf->tail,
+                                silc_buffer_taillen(inbuf));
 
-      if (ret == -1) {
-       /* Cannot read now, do it later. */
-       silc_buffer_pull(&ps->inbuf, silc_buffer_len(&ps->inbuf));
+      if (silc_unlikely(ret < 0)) {
        silc_mutex_unlock(ps->lock);
+       if (ret == -1) {
+         /* Cannot read now, do it later. */
+         silc_buffer_pull(inbuf, silc_buffer_len(inbuf));
+         return FALSE;
+       }
+
+       /* Error */
+       silc_buffer_reset(inbuf);
+       SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_READ);
        return FALSE;
       }
 
       /* See if remote packet stream exist for this sender */
-      snprintf(tuple, sizeof(tuple), "%d%s", remote_port, remote_ip);
-      silc_mutex_lock(ps->engine->lock);
-      if (silc_hash_table_find(ps->engine->udp_remote, tuple, NULL,
+      silc_snprintf(tuple, sizeof(tuple), "%d%s", remote_port, remote_ip);
+      silc_mutex_lock(ps->sc->engine->lock);
+      if (silc_hash_table_find(ps->sc->engine->udp_remote, tuple, NULL,
                               (void *)&remote)) {
-       /* Found packet stream for this sender, copy the packet */
-       silc_mutex_unlock(ps->engine->lock);
-
-       SILC_LOG_DEBUG(("UDP packet from %s:%d for stream %p",
-                       remote_ip, remote_port, remote));
-
+       silc_mutex_unlock(ps->sc->engine->lock);
+       SILC_LOG_DEBUG(("UDP packet from %s:%d for stream %p", remote_ip,
+                       remote_port, remote));
+       silc_mutex_unlock(ps->lock);
        silc_mutex_lock(remote->lock);
-       if (ret > silc_buffer_taillen(&remote->inbuf))
-         if (!silc_buffer_realloc(&remote->inbuf, ret)) {
-           silc_mutex_unlock(remote->lock);
-           silc_mutex_unlock(ps->lock);
-           SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_NO_MEMORY);
-           return FALSE;
-         }
-
-       silc_buffer_put_tail(&remote->inbuf, ps->inbuf.tail, ret);
-       silc_buffer_pull_tail(&remote->inbuf, ret);
        *ret_ps = remote;
-
-       silc_buffer_reset(&ps->inbuf);
-       silc_mutex_unlock(ps->lock);
        return TRUE;
       }
-      silc_mutex_unlock(ps->engine->lock);
+      silc_mutex_unlock(ps->sc->engine->lock);
 
       /* Unknown sender */
       if (!ps->remote_udp) {
        ps->remote_udp = silc_calloc(1, sizeof(*ps->remote_udp));
-       if (!ps->remote_udp) {
+       if (silc_unlikely(!ps->remote_udp)) {
          silc_mutex_unlock(ps->lock);
          SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_NO_MEMORY);
          return FALSE;
@@ -346,39 +354,35 @@ static inline SilcBool silc_packet_stream_read(SilcPacketStream ps,
       ps->remote_udp->remote_ip = strdup(remote_ip);
       ps->remote_udp->remote_port = remote_port;
 
-      silc_buffer_pull_tail(&ps->inbuf, ret);
+      silc_buffer_pull_tail(inbuf, ret);
       return TRUE;
     }
   }
 
   /* Read data from the stream */
-  ret = silc_stream_read(ps->stream, ps->inbuf.tail,
-                        silc_buffer_taillen(&ps->inbuf));
-
-  if (ret == 0) {
-    /* EOS */
-    silc_buffer_reset(&ps->inbuf);
+  ret = silc_stream_read(stream, inbuf->tail, silc_buffer_taillen(inbuf));
+  if (silc_unlikely(ret <= 0)) {
     silc_mutex_unlock(ps->lock);
-    SILC_PACKET_CALLBACK_EOS(ps);
-    return FALSE;
-  }
+    if (ret == 0) {
+      /* EOS */
+      silc_buffer_reset(inbuf);
+      SILC_PACKET_CALLBACK_EOS(ps);
+      return FALSE;
+    }
+
+    if (ret == -1) {
+      /* Cannot read now, do it later. */
+      silc_buffer_pull(inbuf, silc_buffer_len(inbuf));
+      return FALSE;
+    }
 
-  if (ret == -2) {
     /* Error */
-    silc_buffer_reset(&ps->inbuf);
-    silc_mutex_unlock(ps->lock);
+    silc_buffer_reset(inbuf);
     SILC_PACKET_CALLBACK_ERROR(ps, SILC_PACKET_ERR_READ);
     return FALSE;
   }
 
-  if (ret == -1) {
-    /* Cannot read now, do it later. */
-    silc_buffer_pull(&ps->inbuf, silc_buffer_len(&ps->inbuf));
-    silc_mutex_unlock(ps->lock);
-    return FALSE;
-  }
-
-  silc_buffer_pull_tail(&ps->inbuf, ret);
+  silc_buffer_pull_tail(inbuf, ret);
   return TRUE;
 }
 
@@ -391,25 +395,12 @@ static void silc_packet_stream_io(SilcStream stream, SilcStreamStatus status,
 
   silc_mutex_lock(ps->lock);
 
-  if (ps->destroyed) {
+  if (silc_unlikely(ps->destroyed)) {
     silc_mutex_unlock(ps->lock);
     return;
   }
 
   switch (status) {
-
-  case SILC_STREAM_CAN_WRITE:
-    SILC_LOG_DEBUG(("Writing pending data to stream"));
-
-    if (!silc_buffer_headlen(&ps->outbuf)) {
-      silc_mutex_unlock(ps->lock);
-      return;
-    }
-
-    /* Write pending data to stream */
-    silc_packet_stream_write(ps);
-    break;
-
   case SILC_STREAM_CAN_READ:
     SILC_LOG_DEBUG(("Reading data from stream"));
 
@@ -418,6 +409,7 @@ static void silc_packet_stream_io(SilcStream stream, SilcStreamStatus status,
       return;
 
     /* Now process the data */
+    silc_packet_stream_ref(ps);
     if (!remote) {
       silc_packet_read_process(ps);
       silc_mutex_unlock(ps->lock);
@@ -425,6 +417,19 @@ static void silc_packet_stream_io(SilcStream stream, SilcStreamStatus status,
       silc_packet_read_process(remote);
       silc_mutex_unlock(remote->lock);
     }
+    silc_packet_stream_unref(ps);
+    break;
+
+  case SILC_STREAM_CAN_WRITE:
+    SILC_LOG_DEBUG(("Writing pending data to stream"));
+
+    if (silc_unlikely(!silc_buffer_headlen(&ps->outbuf))) {
+      silc_mutex_unlock(ps->lock);
+      return;
+    }
+
+    /* Write pending data to stream */
+    silc_packet_stream_write(ps, FALSE);
     break;
 
   default:
@@ -452,13 +457,13 @@ static SilcPacket silc_packet_alloc(SilcPacketEngine engine)
     silc_mutex_unlock(engine->lock);
 
     packet = silc_calloc(1, sizeof(*packet));
-    if (!packet)
+    if (silc_unlikely(!packet))
       return NULL;
 
     SILC_LOG_DEBUG(("Allocating new packet %p", packet));
 
     tmp = silc_malloc(SILC_PACKET_DEFAULT_SIZE);
-    if (!tmp) {
+    if (silc_unlikely(!tmp)) {
       silc_free(packet);
       return NULL;
     }
@@ -486,6 +491,17 @@ static void silc_packet_engine_hash_destr(void *key, void *context,
   silc_free(key);
 }
 
+/* Per scheduler context hash table destructor */
+
+static void silc_packet_engine_context_destr(void *key, void *context,
+                                            void *user_context)
+{
+  SilcPacketEngineContext sc = context;
+  silc_buffer_clear(&sc->inbuf);
+  silc_buffer_purge(&sc->inbuf);
+  silc_free(sc);
+}
+
 
 /******************************** Packet API ********************************/
 
@@ -512,6 +528,14 @@ silc_packet_engine_start(SilcRng rng, SilcBool router,
   if (!engine)
     return NULL;
 
+  engine->contexts = silc_hash_table_alloc(0, silc_hash_ptr, NULL, NULL, NULL,
+                                          silc_packet_engine_context_destr,
+                                          engine, TRUE);
+  if (!engine->contexts) {
+    silc_free(engine);
+    return NULL;
+  }
+
   engine->rng = rng;
   engine->local_is_router = router;
   engine->callbacks = callbacks;
@@ -576,19 +600,11 @@ SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
   if (!ps)
     return NULL;
 
-  ps->engine = engine;
   ps->stream = stream;
   silc_atomic_init8(&ps->refcnt, 1);
   silc_mutex_alloc(&ps->lock);
 
-  /* Allocate buffers */
-  tmp = silc_malloc(SILC_PACKET_DEFAULT_SIZE);
-  if (!tmp) {
-    silc_packet_stream_destroy(ps);
-    return NULL;
-  }
-  silc_buffer_set(&ps->inbuf, tmp, SILC_PACKET_DEFAULT_SIZE);
-  silc_buffer_reset(&ps->inbuf);
+  /* Allocate out buffer */
   tmp = silc_malloc(SILC_PACKET_DEFAULT_SIZE);
   if (!tmp) {
     silc_packet_stream_destroy(ps);
@@ -604,13 +620,46 @@ SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
     return NULL;
   }
 
-  /* Set IO notifier callback */
-  silc_stream_set_notifier(ps->stream, schedule, silc_packet_stream_io, ps);
-
-  /* Add to engine */
   silc_mutex_lock(engine->lock);
+
+  /* Add per scheduler context */
+  if (!silc_hash_table_find(engine->contexts, schedule, NULL,
+                           (void *)&ps->sc)) {
+    ps->sc = silc_calloc(1, sizeof(*ps->sc));
+    if (!ps->sc) {
+      silc_packet_stream_destroy(ps);
+      silc_mutex_unlock(engine->lock);
+      return NULL;
+    }
+    ps->sc->engine = engine;
+    ps->sc->schedule = schedule;
+
+    /* Allocate data input buffer */
+    tmp = silc_malloc(SILC_PACKET_DEFAULT_SIZE * 31);
+    if (!tmp) {
+      silc_free(ps->sc);
+      ps->sc = NULL;
+      silc_packet_stream_destroy(ps);
+      silc_mutex_unlock(engine->lock);
+      return NULL;
+    }
+    silc_buffer_set(&ps->sc->inbuf, tmp, SILC_PACKET_DEFAULT_SIZE * 31);
+    silc_buffer_reset(&ps->sc->inbuf);
+
+    /* Add to per scheduler context hash table */
+    if (!silc_hash_table_add(engine->contexts, schedule, ps->sc)) {
+      silc_buffer_purge(&ps->sc->inbuf);
+      silc_free(ps->sc);
+      ps->sc = NULL;
+      silc_packet_stream_destroy(ps);
+      silc_mutex_unlock(engine->lock);
+      return NULL;
+    }
+  }
+  ps->sc->stream_count++;
+
+  /* Add the packet stream to engine */
   silc_list_add(engine->streams, ps);
-  silc_mutex_unlock(engine->lock);
 
   /* If this is UDP stream, allocate UDP remote stream hash table */
   if (!engine->udp_remote && silc_socket_stream_is_udp(stream, NULL))
@@ -618,6 +667,10 @@ SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
                                               silc_hash_string_compare, NULL,
                                               silc_packet_engine_hash_destr,
                                               NULL, TRUE);
+  silc_mutex_unlock(engine->lock);
+
+  /* Set IO notifier callback.  This schedules this stream for I/O. */
+  silc_stream_set_notifier(ps->stream, schedule, silc_packet_stream_io, ps);
 
   return ps;
 }
@@ -629,7 +682,7 @@ SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
                                               SilcUInt16 remote_port,
                                               SilcPacket packet)
 {
-  SilcPacketEngine engine = stream->engine;
+  SilcPacketEngine engine = stream->sc->engine;
   SilcPacketStream ps;
   char *tuple;
   void *tmp;
@@ -648,8 +701,8 @@ SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
   ps = silc_calloc(1, sizeof(*ps));
   if (!ps)
     return NULL;
+  ps->sc = stream->sc;
 
-  ps->engine = engine;
   silc_atomic_init8(&ps->refcnt, 1);
   silc_mutex_alloc(&ps->lock);
 
@@ -658,14 +711,7 @@ SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
   ps->stream = (SilcStream)stream;
   ps->udp = TRUE;
 
-  /* Allocate buffers */
-  tmp = silc_malloc(SILC_PACKET_DEFAULT_SIZE);
-  if (!tmp) {
-    silc_packet_stream_destroy(ps);
-    return NULL;
-  }
-  silc_buffer_set(&ps->inbuf, tmp, SILC_PACKET_DEFAULT_SIZE);
-  silc_buffer_reset(&ps->inbuf);
+  /* Allocate out buffer */
   tmp = silc_malloc(SILC_PACKET_DEFAULT_SIZE);
   if (!tmp) {
     silc_packet_stream_destroy(ps);
@@ -707,6 +753,7 @@ SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
   if (packet) {
     /* Inject packet to the new stream */
     packet->stream = ps;
+    silc_packet_stream_ref(ps);
     silc_schedule_task_add_timeout(silc_stream_get_schedule(stream->stream),
                                   silc_packet_stream_inject_packet, packet,
                                   0, 0);
@@ -731,9 +778,17 @@ void silc_packet_stream_destroy(SilcPacketStream stream)
 
   if (!stream->udp) {
     /* Delete from engine */
-    silc_mutex_lock(stream->engine->lock);
-    silc_list_del(stream->engine->streams, stream);
-    silc_mutex_unlock(stream->engine->lock);
+    silc_mutex_lock(stream->sc->engine->lock);
+    silc_list_del(stream->sc->engine->streams, stream);
+
+    /* Remove per scheduler context, if it is not used anymore */
+    if (stream->sc) {
+      stream->sc->stream_count--;
+      if (!stream->sc->stream_count)
+       silc_hash_table_del(stream->sc->engine->contexts,
+                           stream->sc->schedule);
+    }
+    silc_mutex_unlock(stream->sc->engine->lock);
 
     /* Destroy the underlaying stream */
     if (stream->stream)
@@ -741,11 +796,11 @@ void silc_packet_stream_destroy(SilcPacketStream stream)
   } else {
     /* Delete from UDP remote hash table */
     char tuple[64];
-    snprintf(tuple, sizeof(tuple), "%d%s", stream->remote_udp->remote_port,
+    silc_snprintf(tuple, sizeof(tuple), "%d%s", stream->remote_udp->remote_port,
             stream->remote_udp->remote_ip);
-    silc_mutex_lock(stream->engine->lock);
-    silc_hash_table_del(stream->engine->udp_remote, tuple);
-    silc_mutex_unlock(stream->engine->lock);
+    silc_mutex_lock(stream->sc->engine->lock);
+    silc_hash_table_del(stream->sc->engine->udp_remote, tuple);
+    silc_mutex_unlock(stream->sc->engine->lock);
 
     silc_free(stream->remote_udp->remote_ip);
     silc_free(stream->remote_udp);
@@ -755,9 +810,7 @@ void silc_packet_stream_destroy(SilcPacketStream stream)
   }
 
   /* Clear and free buffers */
-  silc_buffer_clear(&stream->inbuf);
   silc_buffer_clear(&stream->outbuf);
-  silc_buffer_purge(&stream->inbuf);
   silc_buffer_purge(&stream->outbuf);
 
   if (stream->process) {
@@ -921,6 +974,13 @@ void silc_packet_stream_unlink(SilcPacketStream stream,
   silc_packet_stream_unref(stream);
 }
 
+/* Returns TRUE if stream is UDP stream */
+
+SilcBool silc_packet_stream_is_udp(SilcPacketStream stream)
+{
+  return stream->udp || silc_socket_stream_is_udp(stream->stream, NULL);
+}
+
 /* Return packet sender IP and port for UDP packet stream */
 
 SilcBool silc_packet_get_sender(SilcPacket packet,
@@ -955,7 +1015,7 @@ void silc_packet_stream_unref(SilcPacketStream stream)
 
 SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream)
 {
-  return stream->engine;
+  return stream->sc->engine;
 }
 
 /* Set application context for packet stream */
@@ -981,13 +1041,13 @@ void *silc_packet_get_context(SilcPacketStream stream)
 /* Change underlaying stream */
 
 void silc_packet_stream_set_stream(SilcPacketStream ps,
-                                  SilcStream stream,
-                                  SilcSchedule schedule)
+                                  SilcStream stream)
 {
   if (ps->stream)
-    silc_stream_set_notifier(ps->stream, schedule, NULL, NULL);
+    silc_stream_set_notifier(ps->stream, ps->sc->schedule, NULL, NULL);
   ps->stream = stream;
-  silc_stream_set_notifier(ps->stream, schedule, silc_packet_stream_io, ps);
+  silc_stream_set_notifier(ps->stream, ps->sc->schedule, silc_packet_stream_io,
+                          ps);
 }
 
 /* Return underlaying stream */
@@ -997,104 +1057,97 @@ SilcStream silc_packet_stream_get_stream(SilcPacketStream stream)
   return stream->stream;
 }
 
-/* Set ciphers for packet stream */
+/* Set keys. */
 
-void silc_packet_set_ciphers(SilcPacketStream stream, SilcCipher send,
-                            SilcCipher receive)
+SilcBool silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
+                              SilcCipher receive_key, SilcHmac send_hmac,
+                              SilcHmac receive_hmac, SilcBool rekey)
 {
-  SILC_LOG_DEBUG(("Setting new ciphers to packet stream"));
+  SILC_LOG_DEBUG(("Setting new keys to packet stream %p", stream));
+
+  /* If doing rekey, send REKEY_DONE packet */
+  if (rekey) {
+    /* This will take stream lock. */
+    if (!silc_packet_send_raw(stream, SILC_PACKET_REKEY_DONE, 0,
+                             stream->src_id_type, stream->src_id,
+                             stream->src_id_len, stream->dst_id_type,
+                             stream->dst_id, stream->dst_id_len,
+                             NULL, 0, stream->send_key[0],
+                             stream->send_hmac[0]))
+      return FALSE;
 
-  silc_mutex_lock(stream->lock);
+    /* Write the packet to the stream */
+    if (!silc_packet_stream_write(stream, TRUE))
+      return FALSE;
+  } else {
+    silc_mutex_lock(stream->lock);
+  }
 
-  /* In case IV Included is set, save the old key */
+  /* In case IV Included is set, save the old keys */
   if (stream->iv_included) {
-    if (stream->send_key[1]) {
+    if (stream->send_key[1] && send_key) {
       silc_cipher_free(stream->send_key[1]);
       stream->send_key[1] = stream->send_key[0];
     }
-    if (stream->receive_key[1]) {
+    if (stream->receive_key[1] && receive_key) {
       silc_cipher_free(stream->receive_key[1]);
       stream->receive_key[1] = stream->receive_key[0];
     }
-  } else {
-    if (stream->send_key[0])
-      silc_cipher_free(stream->send_key[0]);
-    if (stream->send_key[1])
-      silc_cipher_free(stream->receive_key[0]);
-  }
-
-  stream->send_key[0] = send;
-  stream->receive_key[0] = receive;
-
-  silc_mutex_unlock(stream->lock);
-}
-
-/* Return current ciphers from packet stream */
-
-SilcBool silc_packet_get_ciphers(SilcPacketStream stream, SilcCipher *send,
-                                SilcCipher *receive)
-{
-  if (!stream->send_key[0] && !stream->receive_key[0])
-    return FALSE;
-
-  silc_mutex_lock(stream->lock);
-
-  if (send)
-    *send = stream->send_key[0];
-  if (receive)
-    *receive = stream->receive_key[0];
-
-  silc_mutex_unlock(stream->lock);
-
-  return TRUE;
-}
-
-/* Set HMACs for packet stream */
-
-void silc_packet_set_hmacs(SilcPacketStream stream, SilcHmac send,
-                          SilcHmac receive)
-{
-  SILC_LOG_DEBUG(("Setting new HMACs to packet stream"));
-
-  silc_mutex_lock(stream->lock);
-
-  /* In case IV Included is set, save the old HMAC */
-  if (stream->iv_included) {
-    if (stream->send_hmac[1]) {
+    if (stream->send_hmac[1] && send_hmac) {
       silc_hmac_free(stream->send_hmac[1]);
       stream->send_hmac[1] = stream->send_hmac[0];
     }
-    if (stream->receive_hmac[1]) {
+    if (stream->receive_hmac[1] && receive_hmac) {
       silc_hmac_free(stream->receive_hmac[1]);
       stream->receive_hmac[1] = stream->receive_hmac[0];
     }
   } else {
-    if (stream->send_hmac[0])
+    if (stream->send_key[0] && send_key)
+      silc_cipher_free(stream->send_key[0]);
+    if (stream->send_key[1] && receive_key)
+      silc_cipher_free(stream->receive_key[0]);
+    if (stream->send_hmac[0] && send_hmac)
       silc_hmac_free(stream->send_hmac[0]);
-    if (stream->receive_hmac[0])
+    if (stream->receive_hmac[0] && receive_hmac)
       silc_hmac_free(stream->receive_hmac[0]);
   }
 
-  stream->send_hmac[0] = send;
-  stream->receive_hmac[0] = receive;
+  /* Set keys */
+  if (send_key)
+    stream->send_key[0] = send_key;
+  if (receive_key)
+    stream->receive_key[0] = receive_key;
+  if (send_hmac)
+    stream->send_hmac[0] = send_hmac;
+  if (receive_hmac)
+    stream->receive_hmac[0] = receive_hmac;
 
   silc_mutex_unlock(stream->lock);
+  return TRUE;
 }
 
-/* Return current HMACs from packet stream */
+/* Return current ciphers from packet stream */
 
-SilcBool silc_packet_get_hmacs(SilcPacketStream stream, SilcHmac *send,
-                              SilcHmac *receive)
+SilcBool silc_packet_get_keys(SilcPacketStream stream,
+                             SilcCipher *send_key,
+                             SilcCipher *receive_key,
+                             SilcHmac *send_hmac,
+                             SilcHmac *receive_hmac)
 {
-  if (!stream->send_hmac[0] && !stream->receive_hmac[0])
+  if (!stream->send_key[0] && !stream->receive_key[0] &&
+      !stream->send_hmac[0] && !stream->receive_hmac[0])
     return FALSE;
 
   silc_mutex_lock(stream->lock);
 
-  if (send)
-    *send = stream->send_hmac[0];
-  if (receive)
-    *receive = stream->receive_hmac[0];
+  if (send_key)
+    *send_key = stream->send_key[0];
+  if (receive_key)
+    *receive_key = stream->receive_key[0];
+  if (send_hmac)
+    *send_hmac = stream->send_hmac[0];
+  if (receive_hmac)
+    *receive_hmac = stream->receive_hmac[0];
 
   silc_mutex_unlock(stream->lock);
 
@@ -1180,14 +1233,14 @@ void silc_packet_free(SilcPacket packet)
   packet->src_id = packet->dst_id = NULL;
   silc_buffer_reset(&packet->buffer);
 
-  silc_mutex_lock(stream->engine->lock);
+  silc_mutex_lock(stream->sc->engine->lock);
 
   /* Put the packet back to freelist */
-  silc_list_add(stream->engine->packet_pool, packet);
-  if (silc_list_count(stream->engine->packet_pool) == 1)
-    silc_list_start(stream->engine->packet_pool);
+  silc_list_add(stream->sc->engine->packet_pool, packet);
+  if (silc_list_count(stream->sc->engine->packet_pool) == 1)
+    silc_list_start(stream->sc->engine->packet_pool);
 
-  silc_mutex_unlock(stream->engine->lock);
+  silc_mutex_unlock(stream->sc->engine->lock);
 }
 
 /****************************** Packet Sending ******************************/
@@ -1195,10 +1248,10 @@ void silc_packet_free(SilcPacket packet)
 /* Prepare outgoing data buffer for packet sending.  Returns the
    pointer to that buffer into the `packet'. */
 
-static SilcBool silc_packet_send_prepare(SilcPacketStream stream,
-                                        SilcUInt32 totlen,
-                                        SilcHmac hmac,
-                                        SilcBuffer packet)
+static inline SilcBool silc_packet_send_prepare(SilcPacketStream stream,
+                                               SilcUInt32 totlen,
+                                               SilcHmac hmac,
+                                               SilcBuffer packet)
 {
   unsigned char *oldptr;
   unsigned int mac_len = hmac ? silc_hmac_len(hmac) : 0;
@@ -1206,7 +1259,7 @@ static SilcBool silc_packet_send_prepare(SilcPacketStream stream,
   totlen += mac_len;
 
   /* Allocate more space if needed */
-  if (silc_buffer_taillen(&stream->outbuf) < totlen) {
+  if (silc_unlikely(silc_buffer_taillen(&stream->outbuf) < totlen)) {
     if (!silc_buffer_realloc(&stream->outbuf,
                             silc_buffer_truelen(&stream->outbuf) + totlen))
       return FALSE;
@@ -1222,25 +1275,62 @@ static SilcBool silc_packet_send_prepare(SilcPacketStream stream,
   return TRUE;
 }
 
-/* Internal routine to send packet */
-
-static SilcBool silc_packet_send_raw(SilcPacketStream stream,
-                                    SilcPacketType type,
-                                    SilcPacketFlags flags,
-                                    SilcIdType src_id_type,
-                                    unsigned char *src_id,
-                                    SilcUInt32 src_id_len,
-                                    SilcIdType dst_id_type,
-                                    unsigned char *dst_id,
-                                    SilcUInt32 dst_id_len,
-                                    const unsigned char *data,
-                                    SilcUInt32 data_len,
-                                    SilcCipher cipher,
-                                    SilcHmac hmac)
+/* Increments counter when encrypting in counter mode. */
+
+static inline void silc_packet_send_ctr_increment(SilcPacketStream stream,
+                                                 SilcCipher cipher,
+                                                 unsigned char *ret_iv)
+{
+  unsigned char *iv = silc_cipher_get_iv(cipher);
+  SilcUInt32 pc;
+
+  /* Increment packet counter */
+  SILC_GET32_MSB(pc, iv + 8);
+  pc++;
+  SILC_PUT32_MSB(pc, iv + 8);
+
+  /* Reset block counter */
+  memset(iv + 12, 0, 4);
+
+  /* If IV Included flag, return the 64-bit IV for inclusion in packet */
+  if (stream->iv_included) {
+    /* Get new nonce */
+    ret_iv[0] = silc_rng_get_byte_fast(stream->sc->engine->rng);
+    ret_iv[1] = ret_iv[0] + iv[4];
+    ret_iv[2] = ret_iv[0] ^ ret_iv[1];
+    ret_iv[3] = ret_iv[0] + ret_iv[2];
+    SILC_PUT32_MSB(pc, ret_iv + 4);
+    SILC_LOG_HEXDUMP(("IV"), ret_iv, 8);
+
+    /* Set new nonce to counter block */
+    memcpy(iv + 4, ret_iv, 4);
+  }
+
+  SILC_LOG_HEXDUMP(("Counter Block"), iv, 16);
+}
+
+/* Internal routine to assemble outgoing packet.  Assembles and encryptes
+   the packet.  The silc_packet_stream_write needs to be called to send it
+   after this returns TRUE. */
+
+static inline SilcBool silc_packet_send_raw(SilcPacketStream stream,
+                                           SilcPacketType type,
+                                           SilcPacketFlags flags,
+                                           SilcIdType src_id_type,
+                                           unsigned char *src_id,
+                                           SilcUInt32 src_id_len,
+                                           SilcIdType dst_id_type,
+                                           unsigned char *dst_id,
+                                           SilcUInt32 dst_id_len,
+                                           const unsigned char *data,
+                                           SilcUInt32 data_len,
+                                           SilcCipher cipher,
+                                           SilcHmac hmac)
 {
   unsigned char tmppad[SILC_PACKET_MAX_PADLEN], iv[33], psn[4];
   int block_len = (cipher ? silc_cipher_get_block_len(cipher) : 0);
-  int i, enclen, truelen, padlen, ivlen = 0, psnlen = 0;
+  int i, enclen, truelen, padlen = 0, ivlen = 0, psnlen = 0;
+  SilcBool ctr;
   SilcBufferStruct packet;
 
   SILC_LOG_DEBUG(("Sending packet %s (%d) flags %d, src %d dst %d, "
@@ -1255,12 +1345,25 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
   enclen = truelen = (data_len + SILC_PACKET_HEADER_LEN +
                      src_id_len + dst_id_len);
 
-  /* If IV is included, the SID, IV and sequence number is added to packet */
-  if (stream->iv_included && cipher) {
-    psnlen = sizeof(psn);
-    ivlen = block_len + 1;
-    iv[0] = stream->sid;
-    memcpy(iv + 1, silc_cipher_get_iv(cipher), block_len);
+  /* If using CTR mode, increment the counter */
+  ctr = (cipher && silc_cipher_get_mode(cipher) == SILC_CIPHER_MODE_CTR);
+  if (ctr) {
+    silc_packet_send_ctr_increment(stream, cipher, iv + 1);
+
+    /* If IV is included, the SID, IV and sequence number is added to packet */
+    if (stream->iv_included && cipher) {
+      psnlen = sizeof(psn);
+      ivlen = 8 + 1;
+      iv[0] = stream->sid;
+    }
+  } else {
+    /* If IV is included, the SID, IV and sequence number is added to packet */
+    if (stream->iv_included && cipher) {
+      psnlen = sizeof(psn);
+      ivlen = block_len + 1;
+      iv[0] = stream->sid;
+      memcpy(iv + 1, silc_cipher_get_iv(cipher), block_len);
+    }
   }
 
   /* We automatically figure out the packet structure from the packet
@@ -1272,8 +1375,9 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
       type == SILC_PACKET_CHANNEL_MESSAGE) {
 
     /* Padding is calculated from header + IDs */
-    SILC_PACKET_PADLEN((SILC_PACKET_HEADER_LEN + src_id_len + dst_id_len +
-                       psnlen), block_len, padlen);
+    if (!ctr)
+      SILC_PACKET_PADLEN((SILC_PACKET_HEADER_LEN + src_id_len + dst_id_len +
+                         psnlen), block_len, padlen);
 
     /* Length to encrypt, header + IDs + padding. */
     enclen = (SILC_PACKET_HEADER_LEN + src_id_len + dst_id_len +
@@ -1283,7 +1387,7 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
     /* Padding is calculated from true length of the packet */
     if (flags & SILC_PACKET_FLAG_LONG_PAD)
       SILC_PACKET_PADLEN_MAX(truelen + psnlen, block_len, padlen);
-    else
+    else if (!ctr)
       SILC_PACKET_PADLEN(truelen + psnlen, block_len, padlen);
 
     enclen += padlen + psnlen;
@@ -1294,13 +1398,13 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
 
   /* Get random padding */
   for (i = 0; i < padlen; i++) tmppad[i] =
-                                silc_rng_get_byte_fast(stream->engine->rng);
+    silc_rng_get_byte_fast(stream->sc->engine->rng);
 
   silc_mutex_lock(stream->lock);
 
   /* Get packet pointer from the outgoing buffer */
-  if (!silc_packet_send_prepare(stream, truelen + padlen + ivlen + psnlen,
-                               hmac, &packet)) {
+  if (silc_unlikely(!silc_packet_send_prepare(stream, truelen + padlen + ivlen
+                                             + psnlen, hmac, &packet))) {
     silc_mutex_unlock(stream->lock);
     return FALSE;
   }
@@ -1326,7 +1430,7 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
                         SILC_STR_DATA(tmppad, padlen),
                         SILC_STR_DATA(data, data_len),
                         SILC_STR_END);
-  if (i < 0) {
+  if (silc_unlikely(i < 0)) {
     silc_mutex_unlock(stream->lock);
     return FALSE;
   }
@@ -1335,10 +1439,11 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
                   silc_buffer_data(&packet), silc_buffer_len(&packet));
 
   /* Encrypt the packet */
-  if (cipher) {
+  if (silc_likely(cipher)) {
     SILC_LOG_DEBUG(("Encrypting packet"));
-    if (!silc_cipher_encrypt(cipher, packet.data + ivlen,
-                            packet.data + ivlen, enclen, NULL)) {
+    if (silc_unlikely(!silc_cipher_encrypt(cipher, packet.data + ivlen,
+                                          packet.data + ivlen, enclen,
+                                          NULL))) {
       SILC_LOG_ERROR(("Packet encryption failed"));
       silc_mutex_unlock(stream->lock);
       return FALSE;
@@ -1346,7 +1451,7 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
   }
 
   /* Compute HMAC */
-  if (hmac) {
+  if (silc_likely(hmac)) {
     SilcUInt32 mac_len;
 
     /* MAC is computed from the entire encrypted packet data, and put
@@ -1359,8 +1464,7 @@ static SilcBool silc_packet_send_raw(SilcPacketStream stream,
     stream->send_psn++;
   }
 
-  /* Write the packet to the stream */
-  return silc_packet_stream_write(stream);
+  return TRUE;
 }
 
 /* Sends a packet */
@@ -1369,16 +1473,21 @@ SilcBool silc_packet_send(SilcPacketStream stream,
                          SilcPacketType type, SilcPacketFlags flags,
                          const unsigned char *data, SilcUInt32 data_len)
 {
-  return silc_packet_send_raw(stream, type, flags,
-                             stream->src_id_type,
-                             stream->src_id,
-                             stream->src_id_len,
-                             stream->dst_id_type,
-                             stream->dst_id,
-                             stream->dst_id_len,
-                             data, data_len,
-                             stream->send_key[0],
-                             stream->send_hmac[0]);
+  SilcBool ret;
+
+  ret = silc_packet_send_raw(stream, type, flags,
+                            stream->src_id_type,
+                            stream->src_id,
+                            stream->src_id_len,
+                            stream->dst_id_type,
+                            stream->dst_id,
+                            stream->dst_id_len,
+                            data, data_len,
+                            stream->send_key[0],
+                            stream->send_hmac[0]);
+
+  /* Write the packet to the stream */
+  return ret ? silc_packet_stream_write(stream, FALSE) : FALSE;
 }
 
 /* Sends a packet, extended routine */
@@ -1392,6 +1501,7 @@ SilcBool silc_packet_send_ext(SilcPacketStream stream,
 {
   unsigned char src_id_data[32], dst_id_data[32];
   SilcUInt32 src_id_len, dst_id_len;
+  SilcBool ret;
 
   if (src_id)
     if (!silc_id_id2str(src_id, src_id_type, src_id_data,
@@ -1402,16 +1512,19 @@ SilcBool silc_packet_send_ext(SilcPacketStream stream,
                        sizeof(dst_id_data), &dst_id_len))
       return FALSE;
 
-  return silc_packet_send_raw(stream, type, flags,
-                             src_id ? src_id_type : stream->src_id_type,
-                             src_id ? src_id_data : stream->src_id,
-                             src_id ? src_id_len : stream->src_id_len,
-                             dst_id ? dst_id_type : stream->dst_id_type,
-                             dst_id ? dst_id_data : stream->dst_id,
-                             dst_id ? dst_id_len : stream->dst_id_len,
-                             data, data_len,
-                             cipher ? cipher : stream->send_key[0],
-                             hmac ? hmac : stream->send_hmac[0]);
+  ret = silc_packet_send_raw(stream, type, flags,
+                            src_id ? src_id_type : stream->src_id_type,
+                            src_id ? src_id_data : stream->src_id,
+                            src_id ? src_id_len : stream->src_id_len,
+                            dst_id ? dst_id_type : stream->dst_id_type,
+                            dst_id ? dst_id_data : stream->dst_id,
+                            dst_id ? dst_id_len : stream->dst_id_len,
+                            data, data_len,
+                            cipher ? cipher : stream->send_key[0],
+                            hmac ? hmac : stream->send_hmac[0]);
+
+  /* Write the packet to the stream */
+  return ret ? silc_packet_stream_write(stream, FALSE) : FALSE;
 }
 
 /* Sends packet after formatting the arguments to buffer */
@@ -1482,7 +1595,7 @@ static inline SilcBool silc_packet_check_mac(SilcHmac hmac,
                                             SilcUInt32 sequence)
 {
   /* Check MAC */
-  if (hmac) {
+  if (silc_likely(hmac)) {
     unsigned char mac[32], psn[4];
     SilcUInt32 mac_len;
 
@@ -1501,7 +1614,7 @@ static inline SilcBool silc_packet_check_mac(SilcHmac hmac,
     silc_hmac_final(hmac, mac, &mac_len);
 
     /* Compare the MAC's */
-    if (memcmp(packet_mac, mac, mac_len)) {
+    if (silc_unlikely(memcmp(packet_mac, mac, mac_len))) {
       SILC_LOG_DEBUG(("MAC failed"));
       return FALSE;
     }
@@ -1512,6 +1625,30 @@ static inline SilcBool silc_packet_check_mac(SilcHmac hmac,
   return TRUE;
 }
 
+/* Increments/sets counter when decrypting in counter mode. */
+
+static inline void silc_packet_receive_ctr_increment(SilcPacketStream stream,
+                                                    unsigned char *iv,
+                                                    unsigned char *packet_iv)
+{
+  SilcUInt32 pc;
+
+  /* If IV Included flag, set the IV from packet to block counter. */
+  if (stream->iv_included) {
+    memcpy(iv + 4, packet_iv, 8);
+  } else {
+    /* Increment packet counter */
+    SILC_GET32_MSB(pc, iv + 8);
+    pc++;
+    SILC_PUT32_MSB(pc, iv + 8);
+  }
+
+  /* Reset block counter */
+  memset(iv + 12, 0, 4);
+
+  SILC_LOG_HEXDUMP(("Counter Block"), iv, 16);
+}
+
 /* Decrypts SILC packet.  Handles both normal and special packet decryption.
    Return 0 when packet is normal and 1 when it it special, -1 on error. */
 
@@ -1520,18 +1657,19 @@ static inline int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
                                      SilcBool normal)
 {
   if (normal == TRUE) {
-    if (cipher) {
+    if (silc_likely(cipher)) {
       /* Decrypt rest of the packet */
       SILC_LOG_DEBUG(("Decrypting the packet"));
-      if (!silc_cipher_decrypt(cipher, buffer->data, buffer->data,
-                              silc_buffer_len(buffer), NULL))
+      if (silc_unlikely(!silc_cipher_decrypt(cipher, buffer->data,
+                                            buffer->data,
+                                            silc_buffer_len(buffer), NULL)))
        return -1;
     }
     return 0;
 
   } else {
     /* Decrypt rest of the header plus padding */
-    if (cipher) {
+    if (silc_likely(cipher)) {
       SilcUInt16 len;
       SilcUInt32 block_len = silc_cipher_get_block_len(cipher);
 
@@ -1545,13 +1683,13 @@ static inline int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
             block_len);
       silc_buffer_pull(buffer, block_len);
 
-      if (len > silc_buffer_len(buffer)) {
+      if (silc_unlikely(len > silc_buffer_len(buffer))) {
        SILC_LOG_ERROR(("Garbage in header of packet, bad packet length, "
                        "packet dropped"));
        return -1;
       }
-      if (!silc_cipher_decrypt(cipher, buffer->data, buffer->data,
-                              len, NULL))
+      if (silc_unlikely(!silc_cipher_decrypt(cipher, buffer->data,
+                                            buffer->data, len, NULL)))
        return -1;
     }
 
@@ -1580,15 +1718,15 @@ static inline SilcBool silc_packet_parse(SilcPacket packet)
                             SILC_STR_UI_CHAR(&dst_id_len),
                             SILC_STR_UI_CHAR(&src_id_type),
                             SILC_STR_END);
-  if (ret == -1) {
+  if (silc_unlikely(ret == -1)) {
     if (!packet->stream->udp &&
        !silc_socket_stream_is_udp(packet->stream->stream, NULL))
       SILC_LOG_ERROR(("Malformed packet header, packet dropped"));
     return FALSE;
   }
 
-  if (src_id_len > SILC_PACKET_MAX_ID_LEN ||
-      dst_id_len > SILC_PACKET_MAX_ID_LEN) {
+  if (silc_unlikely(src_id_len > SILC_PACKET_MAX_ID_LEN ||
+                   dst_id_len > SILC_PACKET_MAX_ID_LEN)) {
     if (!packet->stream->udp &&
        !silc_socket_stream_is_udp(packet->stream->stream, NULL))
       SILC_LOG_ERROR(("Bad ID lengths in packet (%d and %d)",
@@ -1603,15 +1741,15 @@ static inline SilcBool silc_packet_parse(SilcPacket packet)
                             SILC_STR_DATA(&packet->dst_id, dst_id_len),
                             SILC_STR_OFFSET(padlen),
                             SILC_STR_END);
-  if (ret == -1) {
+  if (silc_unlikely(ret == -1)) {
     if (!packet->stream->udp &&
        !silc_socket_stream_is_udp(packet->stream->stream, NULL))
       SILC_LOG_ERROR(("Malformed packet header, packet dropped"));
     return FALSE;
   }
 
-  if (src_id_type > SILC_ID_CHANNEL ||
-      dst_id_type > SILC_ID_CHANNEL) {
+  if (silc_unlikely(src_id_type > SILC_ID_CHANNEL ||
+                   dst_id_type > SILC_ID_CHANNEL)) {
     if (!packet->stream->udp &&
        !silc_socket_stream_is_udp(packet->stream->stream, NULL))
       SILC_LOG_ERROR(("Bad ID types in packet (%d and %d)",
@@ -1634,9 +1772,10 @@ static inline SilcBool silc_packet_parse(SilcPacket packet)
   return TRUE;
 }
 
-/* Dispatch packet to application.  Called with stream->lock locked. */
+/* Dispatch packet to application.  Called with stream->lock locked.
+   Returns FALSE if the stream was destroyed while dispatching a packet. */
 
-static void silc_packet_dispatch(SilcPacket packet)
+static SilcBool silc_packet_dispatch(SilcPacket packet)
 {
   SilcPacketStream stream = packet->stream;
   SilcPacketProcess p;
@@ -1645,17 +1784,17 @@ static void silc_packet_dispatch(SilcPacket packet)
 
   /* Dispatch packet to all packet processors that want it */
 
-  if (!stream->process) {
+  if (silc_likely(!stream->process)) {
     /* Send to default processor as no others exist */
     SILC_LOG_DEBUG(("Dispatching packet to default callbacks"));
     silc_mutex_unlock(stream->lock);
-    if (!stream->engine->callbacks->
-       packet_receive(stream->engine, stream, packet,
-                      stream->engine->callback_context,
-                      stream->stream_context))
+    if (silc_unlikely(!stream->sc->engine->callbacks->
+                     packet_receive(stream->sc->engine, stream, packet,
+                                    stream->sc->engine->callback_context,
+                                    stream->stream_context)))
       silc_packet_free(packet);
     silc_mutex_lock(stream->lock);
-    return;
+    return stream->destroyed == FALSE;
   }
 
   silc_dlist_start(stream->process);
@@ -1667,12 +1806,12 @@ static void silc_packet_dispatch(SilcPacket packet)
       SILC_LOG_DEBUG(("Dispatching packet to default callbacks"));
       default_sent = TRUE;
       silc_mutex_unlock(stream->lock);
-      if (stream->engine->callbacks->
-         packet_receive(stream->engine, stream, packet,
-                        stream->engine->callback_context,
+      if (stream->sc->engine->callbacks->
+         packet_receive(stream->sc->engine, stream, packet,
+                        stream->sc->engine->callback_context,
                         stream->stream_context)) {
        silc_mutex_lock(stream->lock);
-       return;
+       return stream->destroyed == FALSE;
       }
       silc_mutex_lock(stream->lock);
     }
@@ -1682,11 +1821,11 @@ static void silc_packet_dispatch(SilcPacket packet)
       /* Send all packet types */
       SILC_LOG_DEBUG(("Dispatching packet to %p callbacks", p->callbacks));
       silc_mutex_unlock(stream->lock);
-      if (p->callbacks->packet_receive(stream->engine, stream, packet,
+      if (p->callbacks->packet_receive(stream->sc->engine, stream, packet,
                                       p->callback_context,
                                       stream->stream_context)) {
        silc_mutex_lock(stream->lock);
-       return;
+       return stream->destroyed == FALSE;
       }
       silc_mutex_lock(stream->lock);
     } else {
@@ -1696,11 +1835,11 @@ static void silc_packet_dispatch(SilcPacket packet)
          continue;
        SILC_LOG_DEBUG(("Dispatching packet to %p callbacks", p->callbacks));
        silc_mutex_unlock(stream->lock);
-       if (p->callbacks->packet_receive(stream->engine, stream, packet,
+       if (p->callbacks->packet_receive(stream->sc->engine, stream, packet,
                                         p->callback_context,
                                         stream->stream_context)) {
          silc_mutex_lock(stream->lock);
-         return;
+         return stream->destroyed == FALSE;
        }
        silc_mutex_lock(stream->lock);
        break;
@@ -1712,18 +1851,19 @@ static void silc_packet_dispatch(SilcPacket packet)
     /* Send to default processor as it has not been sent yet */
     SILC_LOG_DEBUG(("Dispatching packet to default callbacks"));
     silc_mutex_unlock(stream->lock);
-    if (stream->engine->callbacks->
-       packet_receive(stream->engine, stream, packet,
-                      stream->engine->callback_context,
+    if (stream->sc->engine->callbacks->
+       packet_receive(stream->sc->engine, stream, packet,
+                      stream->sc->engine->callback_context,
                       stream->stream_context)) {
       silc_mutex_lock(stream->lock);
-      return;
+      return stream->destroyed == FALSE;
     }
     silc_mutex_lock(stream->lock);
   }
 
   /* If we got here, no one wanted the packet, so drop it */
   silc_packet_free(packet);
+  return stream->destroyed == FALSE;
 }
 
 /* Process incoming data and parse packets.  Called with stream->lock
@@ -1731,6 +1871,7 @@ static void silc_packet_dispatch(SilcPacket packet)
 
 static void silc_packet_read_process(SilcPacketStream stream)
 {
+  SilcBuffer inbuf = &stream->sc->inbuf;
   SilcCipher cipher;
   SilcHmac hmac;
   SilcPacket packet;
@@ -1743,33 +1884,42 @@ static void silc_packet_read_process(SilcPacketStream stream)
   int ret;
 
   /* Parse the packets from the data */
-  while (silc_buffer_len(&stream->inbuf) > 0) {
+  while (silc_buffer_len(inbuf) > 0) {
     ivlen = psnlen = 0;
     cipher = stream->receive_key[0];
     hmac = stream->receive_hmac[0];
     normal = FALSE;
 
-    if (silc_buffer_len(&stream->inbuf) <
-       (stream->iv_included ? SILC_PACKET_MIN_HEADER_LEN_IV :
-        SILC_PACKET_MIN_HEADER_LEN)) {
+    if (silc_unlikely(silc_buffer_len(inbuf) <
+                     (stream->iv_included ? SILC_PACKET_MIN_HEADER_LEN_IV :
+                      SILC_PACKET_MIN_HEADER_LEN))) {
       SILC_LOG_DEBUG(("Partial packet in queue, waiting for the rest"));
       return;
     }
 
-    if (hmac)
+    if (silc_likely(hmac))
       mac_len = silc_hmac_len(hmac);
     else
       mac_len = 0;
 
     /* Decrypt first block of the packet to get the length field out */
-    if (cipher) {
+    if (silc_likely(cipher)) {
       block_len = silc_cipher_get_block_len(cipher);
 
       if (stream->iv_included) {
        /* SID, IV and sequence number is included in the ciphertext */
-       sid = (SilcUInt8)stream->inbuf.data[0];
-       memcpy(iv, stream->inbuf.data + 1, block_len);
-       ivlen = block_len + 1;
+       sid = (SilcUInt8)inbuf->data[0];
+
+       if (silc_cipher_get_mode(cipher) == SILC_CIPHER_MODE_CTR) {
+         /* Set the CTR mode IV from packet to counter block */
+         memcpy(iv, silc_cipher_get_iv(cipher), block_len);
+         silc_packet_receive_ctr_increment(stream, iv, inbuf->data + 1);
+         ivlen = 8 + 1;
+       } else {
+         /* Get IV from packet */
+         memcpy(iv, inbuf->data + 1, block_len);
+         ivlen = block_len + 1;
+       }
        psnlen = 4;
 
        /* Check SID, and get correct decryption key */
@@ -1786,15 +1936,19 @@ static void silc_packet_read_process(SilcPacketStream stream)
            silc_mutex_unlock(stream->lock);
            SILC_PACKET_CALLBACK_ERROR(stream, SILC_PACKET_ERR_UNKNOWN_SID);
            silc_mutex_lock(stream->lock);
-           silc_buffer_reset(&stream->inbuf);
+           silc_buffer_reset(inbuf);
            return;
          }
        }
       } else {
        memcpy(iv, silc_cipher_get_iv(cipher), block_len);
+
+       /* If using CTR mode, increment the counter */
+       if (silc_cipher_get_mode(cipher) == SILC_CIPHER_MODE_CTR)
+         silc_packet_receive_ctr_increment(stream, iv, NULL);
       }
 
-      silc_cipher_decrypt(cipher, stream->inbuf.data + ivlen, tmp,
+      silc_cipher_decrypt(cipher, inbuf->data + ivlen, tmp,
                          block_len, iv);
 
       header = tmp;
@@ -1804,60 +1958,62 @@ static void silc_packet_read_process(SilcPacketStream stream)
        header += 4;
       }
     } else {
+      /* Unencrypted packet */
       block_len = SILC_PACKET_MIN_HEADER_LEN;
-      header = stream->inbuf.data;
+      header = inbuf->data;
     }
 
     /* Get packet length and full packet length with padding */
     SILC_PACKET_LENGTH(header, packetlen, paddedlen);
 
     /* Sanity checks */
-    if (packetlen < SILC_PACKET_MIN_LEN) {
+    if (silc_unlikely(packetlen < SILC_PACKET_MIN_LEN)) {
       if (!stream->udp && !silc_socket_stream_is_udp(stream->stream, NULL))
        SILC_LOG_ERROR(("Received too short packet"));
       silc_mutex_unlock(stream->lock);
       SILC_PACKET_CALLBACK_ERROR(stream, SILC_PACKET_ERR_MALFORMED);
       silc_mutex_lock(stream->lock);
       memset(tmp, 0, sizeof(tmp));
-      silc_buffer_reset(&stream->inbuf);
+      silc_buffer_reset(inbuf);
       return;
     }
 
-    if (silc_buffer_len(&stream->inbuf) < paddedlen + ivlen + mac_len) {
+    if (silc_buffer_len(inbuf) < paddedlen + ivlen + mac_len) {
       SILC_LOG_DEBUG(("Received partial packet, waiting for the rest "
                      "(%d bytes)",
-                     paddedlen + mac_len - silc_buffer_len(&stream->inbuf)));
+                     paddedlen + mac_len - silc_buffer_len(inbuf)));
       memset(tmp, 0, sizeof(tmp));
       return;
     }
 
     /* Check MAC of the packet */
-    if (!silc_packet_check_mac(hmac, stream->inbuf.data,
-                              paddedlen + ivlen,
-                              stream->inbuf.data + ivlen + paddedlen,
-                              packet_seq, stream->receive_psn)) {
+    if (silc_unlikely(!silc_packet_check_mac(hmac, inbuf->data,
+                                            paddedlen + ivlen,
+                                            inbuf->data + ivlen +
+                                            paddedlen, packet_seq,
+                                            stream->receive_psn))) {
       silc_mutex_unlock(stream->lock);
       SILC_PACKET_CALLBACK_ERROR(stream, SILC_PACKET_ERR_MAC_FAILED);
       silc_mutex_lock(stream->lock);
       memset(tmp, 0, sizeof(tmp));
-      silc_buffer_reset(&stream->inbuf);
+      silc_buffer_reset(inbuf);
       return;
     }
 
     /* Get packet */
-    packet = silc_packet_alloc(stream->engine);
-    if (!packet) {
+    packet = silc_packet_alloc(stream->sc->engine);
+    if (silc_unlikely(!packet)) {
       silc_mutex_unlock(stream->lock);
       SILC_PACKET_CALLBACK_ERROR(stream, SILC_PACKET_ERR_NO_MEMORY);
       silc_mutex_lock(stream->lock);
       memset(tmp, 0, sizeof(tmp));
-      silc_buffer_reset(&stream->inbuf);
+      silc_buffer_reset(inbuf);
       return;
     }
     packet->stream = stream;
 
     /* Allocate more space to packet buffer, if needed */
-    if (silc_buffer_truelen(&packet->buffer) < paddedlen) {
+    if (silc_unlikely(silc_buffer_truelen(&packet->buffer) < paddedlen)) {
       if (!silc_buffer_realloc(&packet->buffer,
                               silc_buffer_truelen(&packet->buffer) +
                               (paddedlen -
@@ -1867,7 +2023,7 @@ static void silc_packet_read_process(SilcPacketStream stream)
        silc_mutex_lock(stream->lock);
        silc_packet_free(packet);
        memset(tmp, 0, sizeof(tmp));
-       silc_buffer_reset(&stream->inbuf);
+       silc_buffer_reset(inbuf);
        return;
       }
     }
@@ -1876,7 +2032,7 @@ static void silc_packet_read_process(SilcPacketStream stream)
     packet->flags = (SilcPacketFlags)header[2];
     packet->type = (SilcPacketType)header[3];
 
-    if (stream->engine->local_is_router) {
+    if (stream->sc->engine->local_is_router) {
       if (packet->type == SILC_PACKET_PRIVATE_MESSAGE &&
          (packet->flags & SILC_PACKET_FLAG_PRIVMSG_KEY))
        normal = FALSE;
@@ -1894,20 +2050,20 @@ static void silc_packet_read_process(SilcPacketStream stream)
 
     SILC_LOG_HEXDUMP(("Incoming packet (%d) len %d",
                      stream->receive_psn, paddedlen + ivlen + mac_len),
-                    stream->inbuf.data, paddedlen + ivlen + mac_len);
+                    inbuf->data, paddedlen + ivlen + mac_len);
 
     /* Put the decrypted part, and rest of the encrypted data, and decrypt */
     silc_buffer_pull_tail(&packet->buffer, paddedlen);
     silc_buffer_put(&packet->buffer, header, block_len - psnlen);
     silc_buffer_pull(&packet->buffer, block_len - psnlen);
-    silc_buffer_put(&packet->buffer, (stream->inbuf.data + ivlen +
+    silc_buffer_put(&packet->buffer, (inbuf->data + ivlen +
                                      psnlen + (block_len - psnlen)),
                    paddedlen - ivlen - psnlen - (block_len - psnlen));
-    if (cipher) {
+    if (silc_likely(cipher)) {
       silc_cipher_set_iv(cipher, iv);
       ret = silc_packet_decrypt(cipher, hmac, stream->receive_psn,
                                &packet->buffer, normal);
-      if (ret < 0) {
+      if (silc_unlikely(ret < 0)) {
        silc_mutex_unlock(stream->lock);
        SILC_PACKET_CALLBACK_ERROR(stream, SILC_PACKET_ERR_DECRYPTION_FAILED);
        silc_mutex_lock(stream->lock);
@@ -1921,10 +2077,10 @@ static void silc_packet_read_process(SilcPacketStream stream)
     silc_buffer_push(&packet->buffer, block_len);
 
     /* Pull the packet from inbuf thus we'll get the next one in the inbuf. */
-    silc_buffer_pull(&stream->inbuf, paddedlen + mac_len);
+    silc_buffer_pull(inbuf, paddedlen + mac_len);
 
     /* Parse the packet */
-    if (!silc_packet_parse(packet)) {
+    if (silc_unlikely(!silc_packet_parse(packet))) {
       silc_mutex_unlock(stream->lock);
       SILC_PACKET_CALLBACK_ERROR(stream, SILC_PACKET_ERR_MALFORMED);
       silc_mutex_lock(stream->lock);
@@ -1934,10 +2090,11 @@ static void silc_packet_read_process(SilcPacketStream stream)
     }
 
     /* Dispatch the packet to application */
-    silc_packet_dispatch(packet);
+    if (!silc_packet_dispatch(packet))
+      break;
   }
 
-  silc_buffer_reset(&stream->inbuf);
+  silc_buffer_reset(inbuf);
 }
 
 
@@ -1979,7 +2136,7 @@ silc_packet_wait_packet_receive(SilcPacketEngine engine,
   /* Signal the waiting thread for a new packet */
   silc_mutex_lock(pw->wait_lock);
 
-  if (pw->stopped) {
+  if (silc_unlikely(pw->stopped)) {
     silc_mutex_unlock(pw->wait_lock);
     return FALSE;
   }
@@ -2072,7 +2229,7 @@ int silc_packet_wait(void *waiter, int timeout, SilcPacket *return_packet)
 
   /* Wait here until packet has arrived */
   while (silc_list_count(pw->packet_queue) == 0) {
-    if (pw->stopped) {
+    if (silc_unlikely(pw->stopped)) {
       silc_mutex_unlock(pw->wait_lock);
       return -1;
     }