5 Author: Pekka Riikonen <priikone@silcnet.org>
7 Copyright (C) 1997 - 2007 Pekka Riikonen
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; version 2 of the License.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
20 /****h* silccore/Packet Protocol Interface
24 * The SILC secure binary packet protocol interface, provides interface for
25 * sending and receiving SILC packets. The interface provides a packet
26 * engine, that can be used to receive packets from packet streams, and
27 * routines for sending all kinds of SILC packets.
29 * The packet engine and packet stream are thread safe. They can be safely
30 * used in multi threaded environment.
37 /* XXX many of these could go to silcpacket_i.h */
39 /* Maximum packet length */
40 #define SILC_PACKET_MAX_LEN 0xffff
42 /* Maximum length of ID */
43 #define SILC_PACKET_MAX_ID_LEN 28
45 /****d* silccore/SilcPacketAPI/SilcPacketType
49 * typedef SilcUInt8 SilcPacketType;
53 * SILC packet type definition and all the packet types.
57 typedef SilcUInt8 SilcPacketType;
59 /* SILC Packet types. */
60 #define SILC_PACKET_DISCONNECT 1 /* Disconnection */
61 #define SILC_PACKET_SUCCESS 2 /* Success */
62 #define SILC_PACKET_FAILURE 3 /* Failure */
63 #define SILC_PACKET_REJECT 4 /* Rejected */
64 #define SILC_PACKET_NOTIFY 5 /* Notify message */
65 #define SILC_PACKET_ERROR 6 /* Error message */
66 #define SILC_PACKET_CHANNEL_MESSAGE 7 /* Message for channel */
67 #define SILC_PACKET_CHANNEL_KEY 8 /* Key of the channel */
68 #define SILC_PACKET_PRIVATE_MESSAGE 9 /* Private message */
69 #define SILC_PACKET_PRIVATE_MESSAGE_KEY 10 /* Private message key*/
70 #define SILC_PACKET_COMMAND 11 /* Command */
71 #define SILC_PACKET_COMMAND_REPLY 12 /* Reply to a command */
72 #define SILC_PACKET_KEY_EXCHANGE 13 /* Start of KE */
73 #define SILC_PACKET_KEY_EXCHANGE_1 14 /* KE1 */
74 #define SILC_PACKET_KEY_EXCHANGE_2 15 /* KE2 */
75 #define SILC_PACKET_CONNECTION_AUTH_REQUEST 16 /* Request of auth meth */
76 #define SILC_PACKET_CONNECTION_AUTH 17 /* Connectinon auth */
77 #define SILC_PACKET_NEW_ID 18 /* Sending new ID */
78 #define SILC_PACKET_NEW_CLIENT 19 /* Client registering */
79 #define SILC_PACKET_NEW_SERVER 20 /* Server registering */
80 #define SILC_PACKET_NEW_CHANNEL 21 /* Channel registering */
81 #define SILC_PACKET_REKEY 22 /* Re-key start */
82 #define SILC_PACKET_REKEY_DONE 23 /* Re-key done */
83 #define SILC_PACKET_HEARTBEAT 24 /* Heartbeat */
84 #define SILC_PACKET_KEY_AGREEMENT 25 /* Key Agreement request */
85 #define SILC_PACKET_RESUME_ROUTER 26 /* Backup router resume */
86 #define SILC_PACKET_FTP 27 /* File Transfer */
87 #define SILC_PACKET_RESUME_CLIENT 28 /* Client resume */
88 #define SILC_PACKET_ACK 29 /* Acknowledgement */
90 #define SILC_PACKET_PRIVATE 200 /* Private range start */
91 #define SILC_PACKET_MAX 255 /* RESERVED */
93 #define SILC_PACKET_NONE 0 /* RESERVED */
94 #define SILC_PACKET_ANY 0
97 /****d* silccore/SilcPacketAPI/SilcPacketFlags
101 * typedef SilcUInt8 SilcPacketFlags;
105 * SILC packet flags type definition and all the packet flags.
109 typedef SilcUInt8 SilcPacketFlags;
111 /* All defined packet flags */
112 #define SILC_PACKET_FLAG_NONE 0x00 /* No flags */
113 #define SILC_PACKET_FLAG_PRIVMSG_KEY 0x01 /* Private message key */
114 #define SILC_PACKET_FLAG_LIST 0x02 /* Packet is a list */
115 #define SILC_PACKET_FLAG_BROADCAST 0x04 /* Packet is a broadcast */
116 #define SILC_PACKET_FLAG_COMPRESSED 0x08 /* Payload is compressed */
117 #define SILC_PACKET_FLAG_ACK 0x10 /* Acknowledge packet */
119 /* Impelemntation specific flags */
120 #define SILC_PACKET_FLAG_LONG_PAD 0x12 /* Use maximum padding */
123 /****s* silccore/SilcPacketAPI/SilcPacketEngine
127 * typedef struct SilcPacketEngineStruct *SilcPacketEngine;
131 * The packet engine context, allocated by silc_packet_engine_start.
132 * The engine is destroyed with silc_packet_engine_stop.
135 typedef struct SilcPacketEngineStruct *SilcPacketEngine;
137 /****s* silccore/SilcPacketAPI/SilcPacketStream
141 * typedef struct SilcPacketStreamStruct *SilcPacketStream;
145 * The packet stream context, allocated by silc_packet_stream_create.
146 * The stream is destroyed with silc_packet_stream_destroy.
149 typedef struct SilcPacketStreamStruct *SilcPacketStream;
151 /****s* silccore/SilcPacketAPI/SilcPacket
155 * typedef struct SilcPacketStruct *SilcPacket;
159 * The SilcPacket is returned by the packet engine in the SilcPacketReceive
160 * callback. The application can parse the data payload from the
161 * SilcPacket. Also packet type, flags, and sender and destination
162 * IDs are available. The application must free the packet with the
163 * silc_packet_free function if it takes it in for processing.
165 * The `buffer' field contains the parsed packet payload and the start
166 * of the data area will point to the start of the packet payload.
168 * The list pointer `next' can be used by the application to put the
169 * packet context in a list during processing, if needed.
173 typedef struct SilcPacketStruct {
174 struct SilcPacketStruct *next; /* List pointer, application may set */
175 SilcPacketStream stream; /* Packet stream this packet is from */
176 SilcBufferStruct buffer; /* Packet data payload */
177 unsigned char *src_id; /* Source ID */
178 unsigned char *dst_id; /* Destination ID */
179 unsigned int src_id_len : 6; /* Source ID length */
180 unsigned int src_id_type : 2; /* Source ID type */
181 unsigned int dst_id_len : 6; /* Destination ID length */
182 unsigned int dst_id_type : 2; /* Destination ID type */
183 SilcPacketType type; /* Packet type */
184 SilcPacketFlags flags; /* Packet flags */
188 /****d* silcutil/SilcPacketAPI/SilcPacketError
192 * typedef enum { ... } SilcPacketError
196 * Packet errors. This is returned in the error callback. If application
197 * needs the actual lower level stream error, it needs to retrieve it
198 * from the actual stream. It can retrieve the underlaying stream from
199 * the packet stream by calling silc_packet_stream_get_stream function.
204 SILC_PACKET_ERR_READ, /* Error while reading */
205 SILC_PACKET_ERR_WRITE, /* Error while writing */
206 SILC_PACKET_ERR_MAC_FAILED, /* Packet MAC check failed */
207 SILC_PACKET_ERR_DECRYPTION_FAILED, /* Packet decryption failed */
208 SILC_PACKET_ERR_UNKNOWN_SID, /* Unknown SID (with IV included) */
209 SILC_PACKET_ERR_MALFORMED, /* Packet is malformed */
210 SILC_PACKET_ERR_NO_MEMORY, /* System out of memory */
214 /****f* silccore/SilcPacketAPI/SilcPacketReceiveCb
218 * typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
219 * SilcPacketStream stream,
221 * void *callback_context,
222 * void *stream_context);
226 * The packet receive callback is called by the packet engine when a new
227 * SILC Packet has arrived. The application must free the returned
228 * SilcPacket with silc_packet_free if it takes the packet in for
229 * processing. This callback is set in the SilcPacketCallbacks structure.
230 * The `callback_context' is the context set as argument in the
231 * silc_packet_engine_start function. The `stream_context' is stream
232 * specific context that was set by calling silc_packet_set_context.
234 * If the application takes the received packet `packet' into processing
235 * TRUE must be returned. If FALSE is returned the packet engine will
236 * pass the packet to other packet processor, if one has been linked
237 * to the stream with silc_packet_stream_link function. If no extra
238 * processor is linked the packet is dropped.
243 * silc_foo_packet_receive_cb(SilcPacketEngine engine,
244 * SilcPacketStream stream, SilcPacket packet,
245 * void *callback_context, void *stream_context)
247 * Application ctx = callback_context;
249 * // If we're not up yet, let's not process the packet
250 * if (ctx->initialized == FALSE)
253 * // Process the incoming packet...
256 * // It's our packet now, no one else will get it
261 typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
262 SilcPacketStream stream,
264 void *callback_context,
265 void *stream_context);
267 /****f* silccore/SilcPacketAPI/SilcPacketEosCb
271 * typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
272 * SilcPacketStream stream,
273 * void *callback_context,
274 * void *stream_context);
278 * The End Of Stream (EOS) callback, that is called by the packet engine
279 * when the underlaying stream has ended. No more data can be sent to
280 * the stream or read from it. The `stream' must be destroyed by
281 * calling the silc_packet_stream_destroy. This callback is set in the
282 * SilcPacketCallbacks structure.
285 typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
286 SilcPacketStream stream,
287 void *callback_context,
288 void *stream_context);
290 /****f* silccore/SilcPacketAPI/SilcPacketErrorCb
294 * typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
295 * SilcPacketStream stream,
296 * SilcPacketError error,
297 * void *callback_context,
298 * void *stream_context);
302 * The error callback that is called by the packet engine if an error
303 * occurs. The `error' will indicate the error. This callback is set
304 * in the SilcPacketCallbacks structure.
307 typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
308 SilcPacketStream stream,
309 SilcPacketError error,
310 void *callback_context,
311 void *stream_context);
313 /****s* silccore/SilcPacketAPI/SilcPacketStream
317 * typedef struct SilcPacketStreamStruct *SilcPacketStream;
321 * This structure is sent as argument to the silc_packet_engine_start
322 * function to set the callback functions for the packet engine. The
323 * packet engine will call the callbacks when necessary. Application
324 * must always be provided for the packet engine.
329 SilcPacketReceiveCb packet_receive; /* Called when packet is received */
330 SilcPacketEosCb eos; /* Called on end of stream */
331 SilcPacketErrorCb error; /* Called on an error */
332 } SilcPacketCallbacks;
337 /****f* silccore/SilcPacketAPI/silc_packet_engine_start
342 * silc_packet_engine_start(SilcRng rng, SilcBool router,
343 * SilcPacketCallbacks *callbacks,
344 * void *callback_context);
348 * Create new packet engine for processing incoming and outgoing packets.
349 * If `router' is TRUE then the application is considered to be router
350 * server, and certain packets are handled differently. Client and normal
351 * server must set it to FALSE. The `callbacks' is a SilcPacketCallbacks
352 * structure provided by the caller which includes the callbacks that is
353 * called when for example packet is received, or end of stream is called.
357 * The packet engine is thread safe. You can use one packet engine in
358 * multi threaded application.
362 silc_packet_engine_start(SilcRng rng, SilcBool router,
363 SilcPacketCallbacks *callbacks,
364 void *callback_context);
366 /****f* silccore/SilcPacketAPI/silc_packet_engine_stop
370 * void silc_packet_engine_stop(SilcPacketEngine engine);
374 * Stop the packet engine. No new packets can be sent or received after
375 * calling this, and the `engine' will become invalid.
378 void silc_packet_engine_stop(SilcPacketEngine engine);
380 /****f* silccore/SilcPacketAPI/silc_packet_stream_create
384 * SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
385 * SilcSchedule schedule,
386 * SilcStream stream);
390 * Create new packet stream and use the `stream' as underlaying stream.
391 * Usually the `stream' would be a socket stream, but it can be any
392 * stream. After this function returns, packets can immediately be
393 * sent to and received from the stream.
397 * SilcPacketStream cannot be used with silc_stream_* routines (such as
398 * silc_stream_read and silc_stream_write) because of its special nature.
399 * Use the silc_packet_send and the silc_packet_send_ext to send packets.
400 * To read packets you will receive the packet receive callback from
401 * packet engine. Destroy the stream with silc_packet_stream_destroy.
403 * The SilcPacketStream is thread safe. Same context can be safely used
404 * in multi threaded environment.
407 SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
408 SilcSchedule schedule,
411 /****f* silccore/SilcPacketAPI/silc_packet_stream_add_remote
415 * SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
416 * const char *remote_ip,
417 * SilcUInt16 remote_port,
418 * SilcPacket packet);
422 * This function is used to add remote receivers in packet stream `stream'
423 * that has UDP/IP socket stream as the underlaying stream. This function
424 * cannot be used with other type of streams. This returns new packet
425 * stream context that can be used to send to and receive packets from
426 * the specified remote IP and remote port, or NULL on error. The `stream'
427 * is the actual stream that is used to send and receive the data.
429 * When the parent `stream' receives packets from remote IP address
430 * and port that does not have its own remote packet stream, it returns
431 * the packet to the packet callback set for `stream'. The sender's
432 * IP address and port can then be retrieved by using the
433 * silc_packet_get_sender function and to create new packet stream by
434 * calling this function. After that, all packets from that IP address
435 * and port will be received by the new packet stream.
437 * If the `packet' is non-NULL it will be injected into the new packet
438 * stream as soon as the scheduler associated with `stream' schedules
439 * new tasks. It can be used to inject an incoming packet to the stream.
441 * This interface is for connectionless UDP streams. If it is possible
442 * to create connected stream it should be done for performance reasons.
446 * // Create parent packet stream, it can receive packets from anywhere
447 * listener = silc_net_udp_connect("0.0.0.0", 500, NULL, 0, schedule);
448 * parent = silc_packet_stream_create(engine, schedule, listener);
451 * // Received a packet to the parent stream, get the sender information.
452 * silc_packet_get_sender(packet, &ip, &port);
454 * // Create new packet stream for this remote location.
455 * remote = silc_packet_stream_add_remote(parent, ip, port, packet);
458 SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
459 const char *remote_ip,
460 SilcUInt16 remote_port,
463 /****f* silccore/SilcPacketAPI/silc_packet_stream_destroy
467 * void silc_packet_stream_destroy(SilcPacketStream stream);
471 * Destroy packet stream and the underlaying stream. This will also
472 * close and destroy the underlaying stream.
475 void silc_packet_stream_destroy(SilcPacketStream stream);
477 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_router
481 * void silc_packet_stream_set_router(SilcPacketStream stream);
485 * When called sets the stream indicates by `stream' as SILC router
486 * connection stream. This causes that certain packets are handled
487 * differently. This must be called for router connection streams and
488 * must not be called for any other stream.
491 void silc_packet_stream_set_router(SilcPacketStream stream);
493 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_iv_included
497 * void silc_packet_stream_set_iv_included(SilcPacketStream stream);
501 * Sets an IV Included property for the stream indicated by `stream'.
502 * This means that the IV used in the encryption will be included in
503 * the resulted ciphertext. This makes it possible to send and receive
504 * packets on unreliable network transport protocol, such as UDP/IP.
505 * This must be called if the underlaying stream in the `stream' is UDP
508 * When this is set to the stream the silc_packet_set_sid must be called
509 * to set new Security ID. The Security ID will be included with the IV
513 void silc_packet_stream_set_iv_included(SilcPacketStream stream);
515 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_stream
519 * void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
520 * SilcStream stream);
524 * This function may be used to change the underlaying stream in the
525 * packet stream indicated by `packet_stream'. Note that the old
526 * stream will not be used after calling this function. The caller is
527 * responsible destroying the old stream. The `stream' will use
528 * the same scheduler as the `packet_stream'.
531 void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
534 /****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
538 * SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
542 * Returns the actual stream that is associated with the packet stream
543 * `stream'. The caller must not free the returned stream. The returned
544 * stream is the same pointer that was set for silc_packet_stream_create.
545 * This function could be used for example when an error callback is
546 * called by the packet engine to retrieve the actual lower level error
550 SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
552 /****f* silccore/SilcPacketAPI/silc_packet_stream_link
556 * SilcBool silc_packet_stream_link(SilcPacketStream stream,
557 * SilcPacketCallbacks *callbacks,
558 * void *callback_context,
559 * int priority, ...);
563 * Links the packet processing callbacks indicated by `callbacks' into
564 * the packet stream indicated by `stream' with priority `priority' for
565 * the packet types given in the variable argument list. This function
566 * can be used to link to the packet stream for specific packet types
567 * and receive them in the specified callbacks. This way, a third party,
568 * for example some library may attach itself into the packet stream
569 * and receive and process certain packets. The variable argument
570 * list is ended with -1. To link to receive all packets use
573 * The default packet processing callbacks given as argument to the
574 * silc_packet_engine_start has the priority 0. Any priority higher
575 * than 0 will then take precedence over the default callbacks. Any
576 * priority lower than 0 (negative value) will be processed after the
579 * Note that setting only the 'packet_receive' callback in the `callbacks'
584 * // Link to this packet stream, with high priority, for
585 * // SILC_PACKET_CONNECTION_AUTH and SILC_PACKET_CONNECTION_AUTH_REQUEST
586 * // packets. We don't care about other packets.
587 * silc_packet_stream_link(stream, our_callbacks, our_context,
588 * 1000000, SILC_PACKET_CONNECTION_AUTH,
589 * SILC_PACKET_CONNECTION_AUTH_REQUEST, -1);
592 SilcBool silc_packet_stream_link(SilcPacketStream stream,
593 SilcPacketCallbacks *callbacks,
594 void *callback_context,
597 /****f* silccore/SilcPacketAPI/silc_packet_stream_unlink
601 * void silc_packet_stream_unlink(SilcPacketStream stream,
602 * SilcPacketCallbacks *callbacks,
603 * void *callback_context);
607 * Unlinks the `callbacks' with `callback_context' from the packet stream
608 * indicated by `stream'. This function must be called for the callbacks
609 * that was linked to `stream' when they are not needed anymore.
612 void silc_packet_stream_unlink(SilcPacketStream stream,
613 SilcPacketCallbacks *callbacks,
614 void *callback_context);
616 /****f* silccore/SilcPacketAPI/SilcPacketWrapCoder
620 * typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
621 * SilcStreamStatus status,
627 * The encoder/decoder callback for silc_packet_stream_wrap. If the
628 * `status' is SILC_STREAM_CAN_WRITE then additional data can be added
629 * to `buffer'. It is added before the data that is written with
630 * silc_stream_write. The silc_buffer_enlarge should be called to verify
631 * there is enough room in `buffer' before adding data to it. The `buffer'
634 * If the `status' is SILC_STREAM_CAN_READ then data from the `buffer'
635 * may be read before it is passed to readed when silc_stream_read is
636 * called. The `buffer' may be advanced also to hide data in it.
638 * This function returns FALSE in case of error.
641 typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
642 SilcStreamStatus status,
646 /****f* silccore/SilcPacketAPI/silc_packet_stream_wrap
650 * SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
651 * SilcPacketType type,
652 * SilcPacketFlags flags,
653 * SilcBool blocking_mode,
654 * SilcPacketWrapCoder coder,
659 * Wraps the packet stream indicated by `stream' into a SilcStream for
660 * the packet type indicated by `type' with packet flags indicated by
661 * `flags'. The returned SilcStream can be used to read and write the
662 * specified SILC packets with the specified packet flags, by calling
663 * silc_stream_read and silc_stream_write, respectively. The returned
664 * stream can be destroyed by calling silc_stream_destroy. It does not
665 * destroy the wrapped packet stream.
667 * If the `blocking_mode' mode is TRUE then the silc_stream_read and
668 * silc_stream_write may block the calling process or thread until SILC
669 * packet is read or written. If it is FALSE the stream is in non-blocking
670 * mode and the calls never block. The returned stream is thread-safe and
671 * packets may be read and written in multi-threaded environment.
673 * In non-blocking mode the silc_stream_set_notifier must be called before
674 * the returned stream can be used to read packets. The stream status
675 * SILC_STREAM_CAN_READ will be returned to the notifier callback to
676 * indicate that a packet is ready for reading. Calling silc_stream_read
677 * once returns one complete SILC packet data payload (which is of type of
680 * The `coder' is optional encoder/decoder callback which the packet engine
681 * will call if it is non-NULL. It can be used to encode additional data
682 * into each packet when silc_stream_write is called or decode data before
683 * it is passed to reader when silc_stream_read is called. The `context'
684 * is passed to `coder'.
686 * The returned SilcStream can be used as any normal stream and all
687 * SilcStream API functions may be used with the stream. This returns
691 SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
693 SilcPacketFlags flags,
694 SilcBool blocking_mode,
695 SilcPacketWrapCoder coder,
698 /****f* silccore/SilcPacketAPI/silc_packet_get_sender
702 * SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
706 * Returns TRUE if the packet stream indicated by `stream' is using
710 SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
712 /****f* silccore/SilcPacketAPI/silc_packet_get_sender
716 * SilcBool silc_packet_get_sender(SilcPacket packet,
717 * const char **sender_ip,
718 * SilcUInt16 *sender_port);
722 * Returns the packet sender's IP address and port from UDP packet
723 * indicated by `packet'. This can be called only from the packet
724 * callback to retrieve the information of the packet's sender. Returns
725 * FALSE if the information is not available.
728 SilcBool silc_packet_get_sender(SilcPacket packet,
729 const char **sender_ip,
730 SilcUInt16 *sender_port);
732 /****f* silccore/SilcPacketAPI/silc_packet_stream_ref
736 * void silc_packet_stream_ref(SilcPacketStream stream);
740 * Increase reference counter for the stream indicated by `stream'. This
741 * can be used to take a reference for the stream. To unreference the
742 * stream call silc_packet_stream_unref function.
745 void silc_packet_stream_ref(SilcPacketStream stream);
747 /****f* silccore/SilcPacketAPI/silc_packet_stream_unref
751 * void silc_packet_stream_unref(SilcPacketStream stream);
755 * Decrease reference counter for the stream indicated by `stream'. If
756 * the counter hits zero the stream will be destroyed automatically.
759 void silc_packet_stream_unref(SilcPacketStream stream);
761 /****f* silccore/SilcPacketAPI/silc_packet_get_engine
765 * SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
769 * Returns the packet engine from the `stream'.
772 SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
774 /****f* silccore/SilcPacketAPI/silc_packet_set_context
778 * void silc_packet_set_context(SilcPacketStream stream,
779 * void *stream_context);
783 * Sets a stream specific context to the stream. The context will
784 * be delivered to all callback functions, and it can be retrieved by
785 * calling silc_packet_get_context function as well. Note that this is
786 * separate packet stream specific context, and not the same as
787 * `callback_context' in silc_packet_engine_start. Both will be delivered
788 * to the callbacks, and this context as the `stream_context' argument.
791 void silc_packet_set_context(SilcPacketStream stream, void *stream_context);
793 /****f* silccore/SilcPacketAPI/silc_packet_get_context
797 * void *silc_packet_get_context(SilcPacketStream stream);
801 * Returns the current set application context, or NULL if none is set.
804 void *silc_packet_get_context(SilcPacketStream stream);
806 /****f* silccore/SilcPacketAPI/silc_packet_set_keys
810 * void silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
811 * SilcCipher receive_key, SilcHmac send_hmac,
812 * SilcHmac receive_hmac, SilcBool rekey);
816 * Set ciphers and HMACs to be used to encrypt sent packets, and decrypt
817 * received packets. This can be called multiple times to change the
820 * If the `rekey' is TRUE this function will send SILC_PACKET_REKEY_DONE
821 * to the `stream' and will set the new keys. If it is FALSE the keys
822 * are changed but the packet is not changed.
824 * When changing keys the old cipher and HMACs will be freed. If the keys
825 * are not set at all, packets will not be encrypted or decrypted.
828 SilcBool silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
829 SilcCipher receive_key, SilcHmac send_hmac,
830 SilcHmac receive_hmac, SilcBool rekey);
832 /****f* silccore/SilcPacketAPI/silc_packet_get_keys
836 * SilcBool silc_packet_get_keys(SilcPacketStream stream,
837 * SilcCipher *send_key,
838 * SilcCipher *receive_key,
839 * SilcHmac *send_hmac,
840 * SilcHmac *receive_hmac);
844 * Returns the pointers of current ciphers and HMACs from the `stream'.
845 * Returns FALSE if keys are not set.
848 SilcBool silc_packet_get_keys(SilcPacketStream stream,
849 SilcCipher *send_key, SilcCipher *receive_key,
850 SilcHmac *send_hmac, SilcHmac *receive_hmac);
852 /****f* silccore/SilcPacketAPI/silc_packet_set_ids
856 * SilcBool silc_packet_set_ids(SilcPacketStream stream,
857 * SilcIdType src_id_type, const void *src_id
858 * SilcIdType dst_id_type, const void *dst_id);
862 * Set the source ID and destinaion ID to be used when sending packets to
863 * this packet stream. The IDs to be used for a packet stream can be
864 * overridden when sending packets. However, if the IDs do not ever change
865 * for the packet stream it is recommended they are set using this function.
866 * In this case they can be omitted when sending packets to the stream.
867 * It is also possible to set only source or destination ID.
870 SilcBool silc_packet_set_ids(SilcPacketStream stream,
871 SilcIdType src_id_type, const void *src_id,
872 SilcIdType dst_id_type, const void *dst_id);
874 /****f* silccore/SilcPacketAPI/silc_packet_set_sid
878 * SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
882 * Sets new Security ID to the packet stream indicated by `stream'. This
883 * is called only if the IV Included property was set to the stream
884 * by calling silc_packet_stream_set_iv_included. This function sets
885 * new Security ID to the stream which is then included in the ciphertext
886 * of a packet. The `sid' must be 0 when it is set for the very first
887 * time and must be increased by one after each rekey. This function must
888 * be called every time new keys are added to the stream after a rekey.
890 * If this function is called when the IV Included property has not been
891 * set to the stream the `sid' will be ignored. Returns FALSE if the
892 * IV Included has not been set, TRUE otherwise.
895 SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
897 /****f* silccore/SilcPacketAPI/silc_packet_send
901 * SilcBool silc_packet_send(SilcPacketStream stream,
902 * SilcPacketType type, SilcPacketFlags flags,
903 * const unsigned char *data,
904 * SilcUInt32 data_len);
908 * Send `data' of length of `data_len' to the packet stream indicated by
909 * `stream'. If ciphers and HMACs were set using silc_packet_set_keys
910 * the packet will be encrypted and MAC will be computed for it. If
911 * silc_packet_set_ids was used to set source and destination ID for the
912 * packet stream those IDs are used in the packet. If IDs have not been
913 * set and they need to be provided then silc_packet_send_ext function
914 * should be used. Otherwise, the packet will not have IDs set at all.
915 * Returns FALSE if packet could not be sent.
918 SilcBool silc_packet_send(SilcPacketStream stream,
919 SilcPacketType type, SilcPacketFlags flags,
920 const unsigned char *data, SilcUInt32 data_len);
922 /****f* silccore/SilcPacketAPI/silc_packet_send_ext
927 * silc_packet_send_ext(SilcPacketStream stream,
928 * SilcPacketType type, SilcPacketFlags flags,
929 * SilcIdType src_id_type, void *srd_id,
930 * SilcIdType dst_id_type, void *dst_id,
931 * const unsigned char *data, SilcUInt32 data_len,
932 * SilcCipher cipher, SilcHmac hmac);
936 * Same as silc_packet_send but with this function different sending
937 * parameters can be sent as argument. This function can be used to
938 * set specific IDs, cipher and HMAC to be used in packet sending,
939 * instead of the ones saved in the `stream'. If any of the extra
940 * pointers are NULL, default values set to the stream will apply.
943 SilcBool silc_packet_send_ext(SilcPacketStream stream,
944 SilcPacketType type, SilcPacketFlags flags,
945 SilcIdType src_id_type, void *src_id,
946 SilcIdType dst_id_type, void *dst_id,
947 const unsigned char *data, SilcUInt32 data_len,
948 SilcCipher cipher, SilcHmac hmac);
950 /****f* silccore/SilcPacketAPI/silc_packet_send_va
954 * SilcBool silc_packet_send_va(SilcPacketStream stream,
955 * SilcPacketType type,
956 * SilcPacketFlags flags, ...);
960 * Same as silc_packet_send but takes the data in as variable argument
961 * formatted buffer (see silcbuffmt.h). The arguments must be ended
962 * with SILC_STR_END. Returns FALSE if packet could not be sent or
963 * the buffer could not be formatted.
967 * // Send NEW_CLIENT packet
968 * silc_packet_send_va(stream, SILC_PACKET_NEW_CLIENT, 0,
969 * SILC_STR_UI_SHORT(username_len),
970 * SILC_STR_DATA(username, username_len),
971 * SILC_STR_UI_SHORT(realname_len),
972 * SILC_STR_DATA(realname, realname_len),
976 SilcBool silc_packet_send_va(SilcPacketStream stream,
977 SilcPacketType type, SilcPacketFlags flags, ...);
979 /****f* silccore/SilcPacketAPI/silc_packet_send_va_ext
984 * silc_packet_send_va_ext(SilcPacketStream stream,
985 * SilcPacketType type, SilcPacketFlags flags,
986 * SilcIdType src_id_type, void *srd_id,
987 * SilcIdType dst_id_type, void *dst_id,
988 * SilcCipher cipher, SilcHmac hmac, ...);
992 * Same as silc_packet_send_va but with this function different sending
993 * parameters can be sent as argument. This function can be used to
994 * set specific IDs, cipher and HMAC to be used in packet sending,
995 * instead of the ones saved in the `stream'. If any of the extra
996 * pointers are NULL, default values set to the stream will apply.
999 SilcBool silc_packet_send_va_ext(SilcPacketStream stream,
1000 SilcPacketType type, SilcPacketFlags flags,
1001 SilcIdType src_id_type, void *src_id,
1002 SilcIdType dst_id_type, void *dst_id,
1003 SilcCipher cipher, SilcHmac hmac, ...);
1005 /****f* silccore/SilcPacketAPI/silc_packet_wait
1009 * void *silc_packet_wait_init(SilcPacketStream stream, ...);
1013 * Initializes a packet waiter for the packet stream `stream' and
1014 * for the variable argument list of packet types. The function
1015 * silc_packet_wait can be used to block the thread until a packet
1016 * has been received. This function is used to initialize the waiting
1017 * and to give the list of packet types that caller wish to receive.
1018 * The variable argument list must end with -1. To receive all
1019 * packets use SILC_PACKET_ANY. Returns a context that must be given
1020 * to the silc_packet_wait function as argument. Returns NULL on
1021 * error. To uninitialize the waiting call silc_packet_wait_uninit.
1025 * Note that packets may be available immediately after calling this
1026 * function and they will be buffered, until silc_packet_wait is called.
1032 * // Will wait for private message packets
1033 * waiter = silc_packet_wait_init(stream,
1034 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1038 void *silc_packet_wait_init(SilcPacketStream stream, ...);
1040 /****f* silccore/SilcPacketAPI/silc_packet_wait
1044 * void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1048 * Uninitializes the waiting context. This may be called also from
1049 * another thread while other thread is waiting for packets. This will
1050 * inform the waiting thread to stop waiting.
1053 void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1055 /****f* silccore/SilcPacketAPI/silc_packet_wait
1059 * int silc_packet_wait(void *waiter, int timeout,
1060 * SilcPacket *return_packet)
1064 * A special function that can be used to wait for a packet to arrive.
1065 * This function will block the calling process or thread until either
1066 * a packet is received into the `return_packet' pointer or the specified
1067 * timeout value `timeout', which is in milliseconds, will expire. If
1068 * the timeout is 0, no timeout exist. Before calling this function the
1069 * silc_packet_wait_init must be called. The caller is responsible for
1070 * freeing the returned packet with silc_packet_free.
1072 * This function can be used for example from a thread that wants to
1073 * block until SILC packet has been received.
1075 * Returns 1 when packet was received, 0 if timeout occurred and -1 if
1080 * static int foo_read_data(FooContext c)
1082 * SilcPacket packet;
1086 * // Will wait for private message packets
1087 * if (c->initialized == FALSE) {
1088 * waiter = silc_packet_wait_init(stream,
1089 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1090 * c->initialized = TRUE;
1094 * // Wait here until private message packet is received
1095 * if ((silc_packet_wait(waiter, 0, &packet)) < 0)
1098 * ... process packet ...
1104 int silc_packet_wait(void *waiter, int timeout, SilcPacket *return_packet);
1106 /****f* silccore/SilcPacketAPI/silc_packet_free
1110 * void silc_packet_free(SilcPacket packet);
1114 * This function is used to free the SilcPacket pointer that application
1115 * receives in the SilcPacketReceive callback. Application must free
1116 * the packet if it takes it in to processing.
1119 void silc_packet_free(SilcPacket packet);
1121 #endif /* SILCPACKET_H */