Fixed UDP transport handling.
[silc.git] / lib / silccore / silcpacket.h
index 5bf28c99e829397ae280cbe85133964465ff396c..dfc659004a9237b5b218173c9eb79a3bbccebf9a 100644 (file)
@@ -160,6 +160,9 @@ typedef struct SilcPacketStreamStruct *SilcPacketStream;
  *    IDs are available.  The application must free the packet with the
  *    silc_packet_free function if it takes it in for processing.
  *
+ *    The `buffer' field contains the parsed packet payload and the start
+ *    of the data area will point to the start of the packet payload.
+ *
  *    The list pointer `next' can be used by the application to put the
  *    packet context in a list during processing, if needed.
  *
@@ -200,6 +203,7 @@ typedef enum {
   SILC_PACKET_ERR_WRITE,                        /* Error while writing */
   SILC_PACKET_ERR_MAC_FAILED,           /* Packet MAC check failed */
   SILC_PACKET_ERR_DECRYPTION_FAILED,            /* Packet decryption failed */
+  SILC_PACKET_ERR_UNKNOWN_SID,          /* Unknown SID (with IV included) */
   SILC_PACKET_ERR_MALFORMED,            /* Packet is malformed */
   SILC_PACKET_ERR_NO_MEMORY,            /* System out of memory */
 } SilcPacketError;
@@ -384,7 +388,7 @@ void silc_packet_engine_stop(SilcPacketEngine engine);
  *    Create new packet stream and use the `stream' as underlaying stream.
  *    Usually the `stream' would be a socket stream, but it can be any
  *    stream.  After this function returns, packets can immediately be
- *    sent to or received from the stream.
+ *    sent to and received from the stream.
  *
  * NOTES
  *
@@ -402,6 +406,58 @@ SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
                                           SilcSchedule schedule,
                                           SilcStream stream);
 
+/****f* silccore/SilcPacketAPI/silc_packet_stream_add_remote
+ *
+ * SYNOPSIS
+ *
+ *    SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
+ *                                                   const char *remote_ip,
+ *                                                   SilcUInt16 remote_port,
+ *                                                   SilcPacket packet);
+ *
+ * DESCRIPTION
+ *
+ *    This function is used to add remote receivers in packet stream `stream'
+ *    that has UDP/IP socket stream as the underlaying stream.  This function
+ *    cannot be used with other type of streams.  This returns new packet
+ *    stream context that can be used to send to and receive packets from
+ *    the specified remote IP and remote port, or NULL on error.  The `stream'
+ *    is the actual stream that is used to send and receive the data.
+ *
+ *    When the parent `stream' receives packets from remote IP address
+ *    and port that does not have its own remote packet stream, it returns
+ *    the packet to the packet callback set for `stream'.  The sender's
+ *    IP address and port can then be retrieved by using the
+ *    silc_packet_get_sender function and to create new packet stream by
+ *    calling this function.  After that, all packets from that IP address
+ *    and port will be received by the new packet stream.
+ *
+ *    If the `packet' is non-NULL it will be injected into the new packet
+ *    stream as soon as the scheduler associated with `stream' schedules
+ *    new tasks.  It can be used to inject an incoming packet to the stream.
+ *
+ *    This interface is for connectionless UDP streams.  If it is possible
+ *    to create connected stream it should be done for performance reasons.
+ *
+ * EXAMPLE
+ *
+ *    // Create parent packet stream, it can receive packets from anywhere
+ *    listener = silc_net_udp_connect("0.0.0.0", 500, NULL, 0, schedule);
+ *    parent = silc_packet_stream_create(engine, schedule, listener);
+ *
+ *    ...
+ *    // Received a packet to the parent stream, get the sender information.
+ *    silc_packet_get_sender(packet, &ip, &port);
+ *
+ *    // Create new packet stream for this remote location.
+ *    remote = silc_packet_stream_add_remote(parent, ip, port, packet);
+ *
+ ***/
+SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
+                                              const char *remote_ip,
+                                              SilcUInt16 remote_port,
+                                              SilcPacket packet);
+
 /****f* silccore/SilcPacketAPI/silc_packet_stream_destroy
  *
  * SYNOPSIS
@@ -411,7 +467,7 @@ SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
  * DESCRIPTION
  *
  *    Destroy packet stream and the underlaying stream.  This will also
- *    send end of stream to the underlaying stream.
+ *    close and destroy the underlaying stream.
  *
  ***/
 void silc_packet_stream_destroy(SilcPacketStream stream);
@@ -432,6 +488,48 @@ void silc_packet_stream_destroy(SilcPacketStream stream);
  ***/
 void silc_packet_stream_set_router(SilcPacketStream stream);
 
+/****f* silccore/SilcPacketAPI/silc_packet_stream_set_iv_included
+ *
+ * SYNOPSIS
+ *
+ *    void silc_packet_stream_set_iv_included(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ *    Sets an IV Included property for the stream indicated by `stream'.
+ *    This means that the IV used in the encryption will be included in
+ *    the resulted ciphertext.  This makes it possible to send and receive
+ *    packets on unreliable network transport protocol, such as UDP/IP.
+ *    This must be called if the underlaying stream in the `stream' is UDP
+ *    stream.
+ *
+ *    When this is set to the stream the silc_packet_set_sid must be called
+ *    to set new Security ID.  The Security ID will be included with the IV
+ *    in the ciphertext.
+ *
+ ***/
+void silc_packet_stream_set_iv_included(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_set_stream
+ *
+ * SYNOPSIS
+ *
+ *    void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
+ *                                       SilcStream stream,
+ *                                       SilcSchedule schedule);
+ *
+ * DESCRIPTION
+ *
+ *    This function may be used to change the underlaying stream in the
+ *    packet stream indicated by `packet_stream'.  Note that the old
+ *    stream will not be used after calling this function.  The caller is
+ *    responsible destroying the old stream.
+ *
+ ***/
+void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
+                                  SilcStream stream,
+                                  SilcSchedule schedule);
+
 /****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
  *
  * SYNOPSIS
@@ -514,6 +612,26 @@ void silc_packet_stream_unlink(SilcPacketStream stream,
                               SilcPacketCallbacks *callbacks,
                               void *callback_context);
 
+/****f* silccore/SilcPacketAPI/silc_packet_get_sender
+ *
+ * SYNOPSIS
+ *
+ *    SilcBool silc_packet_get_sender(SilcPacket packet,
+ *                                    const char **sender_ip,
+ *                                    SilcUInt16 *sender_port);
+ *
+ * DESCRIPTION
+ *
+ *    Returns the packet sender's IP address and port from UDP packet
+ *    indicated by `packet'.  This can be called only from the packet
+ *    callback to retrieve the information of the packet's sender.  Returns
+ *    FALSE if the information is not available.
+ *
+ ***/
+SilcBool silc_packet_get_sender(SilcPacket packet,
+                               const char **sender_ip,
+                               SilcUInt16 *sender_port);
+
 /****f* silccore/SilcPacketAPI/silc_packet_stream_ref
  *
  * SYNOPSIS
@@ -679,6 +797,29 @@ SilcBool silc_packet_set_ids(SilcPacketStream stream,
                             SilcIdType src_id_type, const void *src_id,
                             SilcIdType dst_id_type, const void *dst_id);
 
+/****f* silccore/SilcPacketAPI/silc_packet_set_sid
+ *
+ * SYNOPSIS
+ *
+ *    SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
+ *
+ * DESCRIPTION
+ *
+ *    Sets new Security ID to the packet stream indicated by `stream'.  This
+ *    is called only if the IV Included property was set to the stream
+ *    by calling silc_packet_stream_set_iv_included.  This function sets
+ *    new Security ID to the stream which is then included in the ciphertext
+ *    of a packet.  The `sid' must be 0 when it is set for the very first
+ *    time and must be increased by one after each rekey.  This function must
+ *    be called every time new keys are added to the stream after a rekey.
+ *
+ *    If this function is called when the IV Included property has not been
+ *    set to the stream the `sid' will be ignored.  Returns FALSE if the
+ *    IV Included has not been set, TRUE otherwise.
+ *
+ ***/
+SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
+
 /****f* silccore/SilcPacketAPI/silc_packet_send
  *
  * SYNOPSIS
@@ -733,6 +874,61 @@ SilcBool silc_packet_send_ext(SilcPacketStream stream,
                              const unsigned char *data, SilcUInt32 data_len,
                              SilcCipher cipher, SilcHmac hmac);
 
+/****f* silccore/SilcPacketAPI/silc_packet_send_va
+ *
+ * SYNOPSIS
+ *
+ *    SilcBool silc_packet_send_va(SilcPacketStream stream,
+ *                                 SilcPacketType type,
+ *                                 SilcPacketFlags flags, ...);
+ *
+ * DESCRIPTION
+ *
+ *    Same as silc_packet_send but takes the data in as variable argument
+ *    formatted buffer (see silcbuffmt.h).  The arguments must be ended
+ *    with SILC_STR_END.  Returns FALSE if packet could not be sent or
+ *    the buffer could not be formatted.
+ *
+ * EXAMPLE
+ *
+ *    // Send NEW_CLIENT packet
+ *    silc_packet_send_va(stream, SILC_PACKET_NEW_CLIENT, 0,
+ *                        SILC_STR_UI_SHORT(username_len),
+ *                        SILC_STR_DATA(username, username_len),
+ *                        SILC_STR_UI_SHORT(realname_len),
+ *                        SILC_STR_DATA(realname, realname_len),
+ *                        SILC_STR_END);
+ *
+ ***/
+SilcBool silc_packet_send_va(SilcPacketStream stream,
+                            SilcPacketType type, SilcPacketFlags flags, ...);
+
+/****f* silccore/SilcPacketAPI/silc_packet_send_va_ext
+ *
+ * SYNOPSIS
+ *
+ *    SilcBool
+ *    silc_packet_send_va_ext(SilcPacketStream stream,
+ *                            SilcPacketType type, SilcPacketFlags flags,
+ *                            SilcIdType src_id_type, void *srd_id,
+ *                            SilcIdType dst_id_type, void *dst_id,
+ *                            SilcCipher cipher, SilcHmac hmac, ...);
+ *
+ * DESCRIPTION
+ *
+ *    Same as silc_packet_send_va but with this function different sending
+ *    parameters can be sent as argument.  This function can be used to
+ *    set specific IDs, cipher and HMAC to be used in packet sending,
+ *    instead of the ones saved in the `stream'.  If any of the extra
+ *    pointers are NULL, default values set to the stream will apply.
+ *
+ ***/
+SilcBool silc_packet_send_va_ext(SilcPacketStream stream,
+                                SilcPacketType type, SilcPacketFlags flags,
+                                SilcIdType src_id_type, void *src_id,
+                                SilcIdType dst_id_type, void *dst_id,
+                                SilcCipher cipher, SilcHmac hmac, ...);
+
 /****f* silccore/SilcPacketAPI/silc_packet_wait
  *
  * SYNOPSIS
@@ -758,11 +954,11 @@ SilcBool silc_packet_send_ext(SilcPacketStream stream,
  *
  * EXAMPLE
  *
- *      void *waiter;
+ *    void *waiter;
  *
- *      // Will wait for private message packets
- *      waiter = silc_packet_wait_init(stream,
- *                                     SILC_PACKET_PRIVATE_MESSAGE, -1);
+ *    // Will wait for private message packets
+ *    waiter = silc_packet_wait_init(stream,
+ *                                   SILC_PACKET_PRIVATE_MESSAGE, -1);
  *
  *
  ***/