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 */
118 /* Impelemntation specific flags */
119 #define SILC_PACKET_FLAG_LONG_PAD 0x10 /* Use maximum padding */
122 /****s* silccore/SilcPacketAPI/SilcPacketEngine
126 * typedef struct SilcPacketEngineStruct *SilcPacketEngine;
130 * The packet engine context, allocated by silc_packet_engine_start.
131 * The engine is destroyed with silc_packet_engine_stop.
134 typedef struct SilcPacketEngineStruct *SilcPacketEngine;
136 /****s* silccore/SilcPacketAPI/SilcPacketStream
140 * typedef struct SilcPacketStreamStruct *SilcPacketStream;
144 * The packet stream context, allocated by silc_packet_stream_create.
145 * The stream is destroyed with silc_packet_stream_destroy.
148 typedef struct SilcPacketStreamStruct *SilcPacketStream;
150 /****s* silccore/SilcPacketAPI/SilcPacket
154 * typedef struct SilcPacketStruct *SilcPacket;
158 * The SilcPacket is returned by the packet engine in the SilcPacketReceive
159 * callback. The application can parse the data payload from the
160 * SilcPacket. Also packet type, flags, and sender and destination
161 * IDs are available. The application must free the packet with the
162 * silc_packet_free function if it takes it in for processing.
164 * The `buffer' field contains the parsed packet payload and the start
165 * of the data area will point to the start of the packet payload.
167 * The list pointer `next' can be used by the application to put the
168 * packet context in a list during processing, if needed.
172 typedef struct SilcPacketStruct {
173 struct SilcPacketStruct *next; /* List pointer, application may set */
174 SilcPacketStream stream; /* Packet stream this packet is from */
175 SilcBufferStruct buffer; /* Packet data payload */
176 unsigned char *src_id; /* Source ID */
177 unsigned char *dst_id; /* Destination ID */
178 unsigned int src_id_len : 6; /* Source ID length */
179 unsigned int src_id_type : 2; /* Source ID type */
180 unsigned int dst_id_len : 6; /* Destination ID length */
181 unsigned int dst_id_type : 2; /* Destination ID type */
182 SilcPacketType type; /* Packet type */
183 SilcPacketFlags flags; /* Packet flags */
187 /****d* silcutil/SilcPacketAPI/SilcPacketError
191 * typedef enum { ... } SilcPacketError
195 * Packet errors. This is returned in the error callback. If application
196 * needs the actual lower level stream error, it needs to retrieve it
197 * from the actual stream. It can retrieve the underlaying stream from
198 * the packet stream by calling silc_packet_stream_get_stream function.
203 SILC_PACKET_ERR_READ, /* Error while reading */
204 SILC_PACKET_ERR_WRITE, /* Error while writing */
205 SILC_PACKET_ERR_MAC_FAILED, /* Packet MAC check failed */
206 SILC_PACKET_ERR_DECRYPTION_FAILED, /* Packet decryption failed */
207 SILC_PACKET_ERR_UNKNOWN_SID, /* Unknown SID (with IV included) */
208 SILC_PACKET_ERR_MALFORMED, /* Packet is malformed */
209 SILC_PACKET_ERR_NO_MEMORY, /* System out of memory */
213 /****f* silccore/SilcPacketAPI/SilcPacketReceiveCb
217 * typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
218 * SilcPacketStream stream,
220 * void *callback_context,
221 * void *stream_context);
225 * The packet receive callback is called by the packet engine when a new
226 * SILC Packet has arrived. The application must free the returned
227 * SilcPacket with silc_packet_free if it takes the packet in for
228 * processing. This callback is set in the SilcPacketCallbacks structure.
229 * The `callback_context' is the context set as argument in the
230 * silc_packet_engine_start function. The `stream_context' is stream
231 * specific context that was set by calling silc_packet_set_context.
233 * If the application takes the received packet `packet' into processing
234 * TRUE must be returned. If FALSE is returned the packet engine will
235 * pass the packet to other packet processor, if one has been linked
236 * to the stream with silc_packet_stream_link function. If no extra
237 * processor is linked the packet is dropped.
242 * silc_foo_packet_receive_cb(SilcPacketEngine engine,
243 * SilcPacketStream stream, SilcPacket packet,
244 * void *callback_context, void *stream_context)
246 * Application ctx = callback_context;
248 * // If we're not up yet, let's not process the packet
249 * if (ctx->initialized == FALSE)
252 * // Process the incoming packet...
255 * // It's our packet now, no one else will get it
260 typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
261 SilcPacketStream stream,
263 void *callback_context,
264 void *stream_context);
266 /****f* silccore/SilcPacketAPI/SilcPacketEosCb
270 * typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
271 * SilcPacketStream stream,
272 * void *callback_context,
273 * void *stream_context);
277 * The End Of Stream (EOS) callback, that is called by the packet engine
278 * when the underlaying stream has ended. No more data can be sent to
279 * the stream or read from it. The `stream' must be destroyed by
280 * calling the silc_packet_stream_destroy. This callback is set in the
281 * SilcPacketCallbacks structure.
284 typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
285 SilcPacketStream stream,
286 void *callback_context,
287 void *stream_context);
289 /****f* silccore/SilcPacketAPI/SilcPacketErrorCb
293 * typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
294 * SilcPacketStream stream,
295 * SilcPacketError error,
296 * void *callback_context,
297 * void *stream_context);
301 * The error callback that is called by the packet engine if an error
302 * occurs. The `error' will indicate the error. This callback is set
303 * in the SilcPacketCallbacks structure.
306 typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
307 SilcPacketStream stream,
308 SilcPacketError error,
309 void *callback_context,
310 void *stream_context);
312 /****s* silccore/SilcPacketAPI/SilcPacketStream
316 * typedef struct SilcPacketStreamStruct *SilcPacketStream;
320 * This structure is sent as argument to the silc_packet_engine_start
321 * function to set the callback functions for the packet engine. The
322 * packet engine will call the callbacks when necessary. Application
323 * must always be provided for the packet engine.
328 SilcPacketReceiveCb packet_receive; /* Called when packet is received */
329 SilcPacketEosCb eos; /* Called on end of stream */
330 SilcPacketErrorCb error; /* Called on an error */
331 } SilcPacketCallbacks;
336 /****f* silccore/SilcPacketAPI/silc_packet_engine_start
341 * silc_packet_engine_start(SilcRng rng, SilcBool router,
342 * SilcPacketCallbacks *callbacks,
343 * void *callback_context);
347 * Create new packet engine for processing incoming and outgoing packets.
348 * If `router' is TRUE then the application is considered to be router
349 * server, and certain packets are handled differently. Client and normal
350 * server must set it to FALSE. The `callbacks' is a SilcPacketCallbacks
351 * structure provided by the caller which includes the callbacks that is
352 * called when for example packet is received, or end of stream is called.
356 * The packet engine is thread safe. You can use one packet engine in
357 * multi threaded application.
361 silc_packet_engine_start(SilcRng rng, SilcBool router,
362 SilcPacketCallbacks *callbacks,
363 void *callback_context);
365 /****f* silccore/SilcPacketAPI/silc_packet_engine_stop
369 * void silc_packet_engine_stop(SilcPacketEngine engine);
373 * Stop the packet engine. No new packets can be sent or received after
374 * calling this, and the `engine' will become invalid.
377 void silc_packet_engine_stop(SilcPacketEngine engine);
379 /****f* silccore/SilcPacketAPI/silc_packet_stream_create
383 * SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
384 * SilcSchedule schedule,
385 * SilcStream stream);
389 * Create new packet stream and use the `stream' as underlaying stream.
390 * Usually the `stream' would be a socket stream, but it can be any
391 * stream. After this function returns, packets can immediately be
392 * sent to and received from the stream.
396 * SilcPacketStream cannot be used with silc_stream_* routines (such as
397 * silc_stream_read and silc_stream_write) because of its special nature.
398 * Use the silc_packet_send and the silc_packet_send_ext to send packets.
399 * To read packets you will receive the packet receive callback from
400 * packet engine. Destroy the stream with silc_packet_stream_destroy.
402 * The SilcPacketStream is thread safe. Same context can be safely used
403 * in multi threaded environment.
406 SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
407 SilcSchedule schedule,
410 /****f* silccore/SilcPacketAPI/silc_packet_stream_add_remote
414 * SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
415 * const char *remote_ip,
416 * SilcUInt16 remote_port,
417 * SilcPacket packet);
421 * This function is used to add remote receivers in packet stream `stream'
422 * that has UDP/IP socket stream as the underlaying stream. This function
423 * cannot be used with other type of streams. This returns new packet
424 * stream context that can be used to send to and receive packets from
425 * the specified remote IP and remote port, or NULL on error. The `stream'
426 * is the actual stream that is used to send and receive the data.
428 * When the parent `stream' receives packets from remote IP address
429 * and port that does not have its own remote packet stream, it returns
430 * the packet to the packet callback set for `stream'. The sender's
431 * IP address and port can then be retrieved by using the
432 * silc_packet_get_sender function and to create new packet stream by
433 * calling this function. After that, all packets from that IP address
434 * and port will be received by the new packet stream.
436 * If the `packet' is non-NULL it will be injected into the new packet
437 * stream as soon as the scheduler associated with `stream' schedules
438 * new tasks. It can be used to inject an incoming packet to the stream.
440 * This interface is for connectionless UDP streams. If it is possible
441 * to create connected stream it should be done for performance reasons.
445 * // Create parent packet stream, it can receive packets from anywhere
446 * listener = silc_net_udp_connect("0.0.0.0", 500, NULL, 0, schedule);
447 * parent = silc_packet_stream_create(engine, schedule, listener);
450 * // Received a packet to the parent stream, get the sender information.
451 * silc_packet_get_sender(packet, &ip, &port);
453 * // Create new packet stream for this remote location.
454 * remote = silc_packet_stream_add_remote(parent, ip, port, packet);
457 SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
458 const char *remote_ip,
459 SilcUInt16 remote_port,
462 /****f* silccore/SilcPacketAPI/silc_packet_stream_destroy
466 * void silc_packet_stream_destroy(SilcPacketStream stream);
470 * Destroy packet stream and the underlaying stream. This will also
471 * close and destroy the underlaying stream.
474 void silc_packet_stream_destroy(SilcPacketStream stream);
476 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_router
480 * void silc_packet_stream_set_router(SilcPacketStream stream);
484 * When called sets the stream indicates by `stream' as SILC router
485 * connection stream. This causes that certain packets are handled
486 * differently. This must be called for router connection streams and
487 * must not be called for any other stream.
490 void silc_packet_stream_set_router(SilcPacketStream stream);
492 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_iv_included
496 * void silc_packet_stream_set_iv_included(SilcPacketStream stream);
500 * Sets an IV Included property for the stream indicated by `stream'.
501 * This means that the IV used in the encryption will be included in
502 * the resulted ciphertext. This makes it possible to send and receive
503 * packets on unreliable network transport protocol, such as UDP/IP.
504 * This must be called if the underlaying stream in the `stream' is UDP
507 * When this is set to the stream the silc_packet_set_sid must be called
508 * to set new Security ID. The Security ID will be included with the IV
512 void silc_packet_stream_set_iv_included(SilcPacketStream stream);
514 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_stream
518 * void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
519 * SilcStream stream);
523 * This function may be used to change the underlaying stream in the
524 * packet stream indicated by `packet_stream'. Note that the old
525 * stream will not be used after calling this function. The caller is
526 * responsible destroying the old stream. The `stream' will use
527 * the same scheduler as the `packet_stream'.
530 void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
533 /****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
537 * SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
541 * Returns the actual stream that is associated with the packet stream
542 * `stream'. The caller must not free the returned stream. The returned
543 * stream is the same pointer that was set for silc_packet_stream_create.
544 * This function could be used for example when an error callback is
545 * called by the packet engine to retrieve the actual lower level error
549 SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
551 /****f* silccore/SilcPacketAPI/silc_packet_stream_link
555 * SilcBool silc_packet_stream_link(SilcPacketStream stream,
556 * SilcPacketCallbacks *callbacks,
557 * void *callback_context,
558 * int priority, ...);
562 * Links the packet processing callbacks indicated by `callbacks' into
563 * the packet stream indicated by `stream' with priority `priority' for
564 * the packet types given in the variable argument list. This function
565 * can be used to link to the packet stream for specific packet types
566 * and receive them in the specified callbacks. This way, a third party,
567 * for example some library may attach itself into the packet stream
568 * and receive and process certain packets. The variable argument
569 * list is ended with -1. To link to receive all packets use
572 * The default packet processing callbacks given as argument to the
573 * silc_packet_engine_start has the priority 0. Any priority higher
574 * than 0 will then take precedence over the default callbacks. Any
575 * priority lower than 0 (negative value) will be processed after the
578 * Note that setting only the 'packet_receive' callback in the `callbacks'
583 * // Link to this packet stream, with high priority, for
584 * // SILC_PACKET_CONNECTION_AUTH and SILC_PACKET_CONNECTION_AUTH_REQUEST
585 * // packets. We don't care about other packets.
586 * silc_packet_stream_link(stream, our_callbacks, our_context,
587 * 1000000, SILC_PACKET_CONNECTION_AUTH,
588 * SILC_PACKET_CONNECTION_AUTH_REQUEST, -1);
591 SilcBool silc_packet_stream_link(SilcPacketStream stream,
592 SilcPacketCallbacks *callbacks,
593 void *callback_context,
596 /****f* silccore/SilcPacketAPI/silc_packet_stream_unlink
600 * void silc_packet_stream_unlink(SilcPacketStream stream,
601 * SilcPacketCallbacks *callbacks,
602 * void *callback_context);
606 * Unlinks the `callbacks' with `callback_context' from the packet stream
607 * indicated by `stream'. This function must be called for the callbacks
608 * that was linked to `stream' when they are not needed anymore.
611 void silc_packet_stream_unlink(SilcPacketStream stream,
612 SilcPacketCallbacks *callbacks,
613 void *callback_context);
615 /****f* silccore/SilcPacketAPI/silc_packet_stream_wrap
619 * SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
620 * SilcPacketType type,
621 * SilcPacketFlags flags);
625 * Wraps the packet stream indicated by `stream' into a SilcStream for
626 * the packet type indicated by `type' with packet flags indicated by
627 * `flags'. The returned SilcStream can be used to read and write the
628 * specified SILC packets with the specified packet flags, by calling
629 * silc_stream_read and silc_stream_write, respectively. The returned
630 * stream can be destroyed by calling silc_stream_destroy. It does not
631 * destroy the wrapped packet stream.
633 * The silc_stream_set_notifier must be called before the returned stream
634 * can be used to receive packets. The SILC_STREAM_CAN_READ will be
635 * returned to the notifier callback to indicate that a packet is ready
636 * for reading. Calling silc_stream_read once returns one complete SILC
637 * packet data payload (which is of type of `type').
639 * The returned SilcStream can be used as any normal stream and all
640 * SilcStream API functions may be used with the stream. This returns
644 SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
646 SilcPacketFlags flags);
648 /****f* silccore/SilcPacketAPI/silc_packet_get_sender
652 * SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
656 * Returns TRUE if the packet stream indicated by `stream' is using
660 SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
662 /****f* silccore/SilcPacketAPI/silc_packet_get_sender
666 * SilcBool silc_packet_get_sender(SilcPacket packet,
667 * const char **sender_ip,
668 * SilcUInt16 *sender_port);
672 * Returns the packet sender's IP address and port from UDP packet
673 * indicated by `packet'. This can be called only from the packet
674 * callback to retrieve the information of the packet's sender. Returns
675 * FALSE if the information is not available.
678 SilcBool silc_packet_get_sender(SilcPacket packet,
679 const char **sender_ip,
680 SilcUInt16 *sender_port);
682 /****f* silccore/SilcPacketAPI/silc_packet_stream_ref
686 * void silc_packet_stream_ref(SilcPacketStream stream);
690 * Increase reference counter for the stream indicated by `stream'. This
691 * can be used to take a reference for the stream. To unreference the
692 * stream call silc_packet_stream_unref function.
695 void silc_packet_stream_ref(SilcPacketStream stream);
697 /****f* silccore/SilcPacketAPI/silc_packet_stream_unref
701 * void silc_packet_stream_unref(SilcPacketStream stream);
705 * Decrease reference counter for the stream indicated by `stream'. If
706 * the counter hits zero the stream will be destroyed automatically.
709 void silc_packet_stream_unref(SilcPacketStream stream);
711 /****f* silccore/SilcPacketAPI/silc_packet_get_engine
715 * SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
719 * Returns the packet engine from the `stream'.
722 SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
724 /****f* silccore/SilcPacketAPI/silc_packet_set_context
728 * void silc_packet_set_context(SilcPacketStream stream,
729 * void *stream_context);
733 * Sets a stream specific context to the stream. The context will
734 * be delivered to all callback functions, and it can be retrieved by
735 * calling silc_packet_get_context function as well. Note that this is
736 * separate packet stream specific context, and not the same as
737 * `callback_context' in silc_packet_engine_start. Both will be delivered
738 * to the callbacks, and this context as the `stream_context' argument.
741 void silc_packet_set_context(SilcPacketStream stream, void *stream_context);
743 /****f* silccore/SilcPacketAPI/silc_packet_get_context
747 * void *silc_packet_get_context(SilcPacketStream stream);
751 * Returns the current set application context, or NULL if none is set.
754 void *silc_packet_get_context(SilcPacketStream stream);
756 /****f* silccore/SilcPacketAPI/silc_packet_set_keys
760 * void silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
761 * SilcCipher receive_key, SilcHmac send_hmac,
762 * SilcHmac receive_hmac, SilcBool rekey);
766 * Set ciphers and HMACs to be used to encrypt sent packets, and decrypt
767 * received packets. This can be called multiple times to change the
770 * If the `rekey' is TRUE this function will send SILC_PACKET_REKEY_DONE
771 * to the `stream' and will set the new keys. If it is FALSE the keys
772 * are changed but the packet is not changed.
774 * When changing keys the old cipher and HMACs will be freed. If the keys
775 * are not set at all, packets will not be encrypted or decrypted.
778 SilcBool silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
779 SilcCipher receive_key, SilcHmac send_hmac,
780 SilcHmac receive_hmac, SilcBool rekey);
782 /****f* silccore/SilcPacketAPI/silc_packet_get_keys
786 * SilcBool silc_packet_get_keys(SilcPacketStream stream,
787 * SilcCipher *send_key,
788 * SilcCipher *receive_key,
789 * SilcHmac *send_hmac,
790 * SilcHmac *receive_hmac);
794 * Returns the pointers of current ciphers and HMACs from the `stream'.
795 * Returns FALSE if keys are not set.
798 SilcBool silc_packet_get_keys(SilcPacketStream stream,
799 SilcCipher *send_key, SilcCipher *receive_key,
800 SilcHmac *send_hmac, SilcHmac *receive_hmac);
802 /****f* silccore/SilcPacketAPI/silc_packet_set_ids
806 * SilcBool silc_packet_set_ids(SilcPacketStream stream,
807 * SilcIdType src_id_type, const void *src_id
808 * SilcIdType dst_id_type, const void *dst_id);
812 * Set the source ID and destinaion ID to be used when sending packets to
813 * this packet stream. The IDs to be used for a packet stream can be
814 * overridden when sending packets. However, if the IDs do not ever change
815 * for the packet stream it is recommended they are set using this function.
816 * In this case they can be omitted when sending packets to the stream.
817 * It is also possible to set only source or destination ID.
820 SilcBool silc_packet_set_ids(SilcPacketStream stream,
821 SilcIdType src_id_type, const void *src_id,
822 SilcIdType dst_id_type, const void *dst_id);
824 /****f* silccore/SilcPacketAPI/silc_packet_set_sid
828 * SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
832 * Sets new Security ID to the packet stream indicated by `stream'. This
833 * is called only if the IV Included property was set to the stream
834 * by calling silc_packet_stream_set_iv_included. This function sets
835 * new Security ID to the stream which is then included in the ciphertext
836 * of a packet. The `sid' must be 0 when it is set for the very first
837 * time and must be increased by one after each rekey. This function must
838 * be called every time new keys are added to the stream after a rekey.
840 * If this function is called when the IV Included property has not been
841 * set to the stream the `sid' will be ignored. Returns FALSE if the
842 * IV Included has not been set, TRUE otherwise.
845 SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
847 /****f* silccore/SilcPacketAPI/silc_packet_send
851 * SilcBool silc_packet_send(SilcPacketStream stream,
852 * SilcPacketType type, SilcPacketFlags flags,
853 * const unsigned char *data,
854 * SilcUInt32 data_len);
858 * Send `data' of length of `data_len' to the packet stream indicated by
859 * `stream'. If ciphers and HMACs were set using silc_packet_set_keys
860 * the packet will be encrypted and MAC will be computed for it. If
861 * silc_packet_set_ids was used to set source and destination ID for the
862 * packet stream those IDs are used in the packet. If IDs have not been
863 * set and they need to be provided then silc_packet_send_ext function
864 * should be used. Otherwise, the packet will not have IDs set at all.
865 * Returns FALSE if packet could not be sent.
868 SilcBool silc_packet_send(SilcPacketStream stream,
869 SilcPacketType type, SilcPacketFlags flags,
870 const unsigned char *data, SilcUInt32 data_len);
872 /****f* silccore/SilcPacketAPI/silc_packet_send_ext
877 * silc_packet_send_ext(SilcPacketStream stream,
878 * SilcPacketType type, SilcPacketFlags flags,
879 * SilcIdType src_id_type, void *srd_id,
880 * SilcIdType dst_id_type, void *dst_id,
881 * const unsigned char *data, SilcUInt32 data_len,
882 * SilcCipher cipher, SilcHmac hmac);
886 * Same as silc_packet_send but with this function different sending
887 * parameters can be sent as argument. This function can be used to
888 * set specific IDs, cipher and HMAC to be used in packet sending,
889 * instead of the ones saved in the `stream'. If any of the extra
890 * pointers are NULL, default values set to the stream will apply.
893 SilcBool silc_packet_send_ext(SilcPacketStream stream,
894 SilcPacketType type, SilcPacketFlags flags,
895 SilcIdType src_id_type, void *src_id,
896 SilcIdType dst_id_type, void *dst_id,
897 const unsigned char *data, SilcUInt32 data_len,
898 SilcCipher cipher, SilcHmac hmac);
900 /****f* silccore/SilcPacketAPI/silc_packet_send_va
904 * SilcBool silc_packet_send_va(SilcPacketStream stream,
905 * SilcPacketType type,
906 * SilcPacketFlags flags, ...);
910 * Same as silc_packet_send but takes the data in as variable argument
911 * formatted buffer (see silcbuffmt.h). The arguments must be ended
912 * with SILC_STR_END. Returns FALSE if packet could not be sent or
913 * the buffer could not be formatted.
917 * // Send NEW_CLIENT packet
918 * silc_packet_send_va(stream, SILC_PACKET_NEW_CLIENT, 0,
919 * SILC_STR_UI_SHORT(username_len),
920 * SILC_STR_DATA(username, username_len),
921 * SILC_STR_UI_SHORT(realname_len),
922 * SILC_STR_DATA(realname, realname_len),
926 SilcBool silc_packet_send_va(SilcPacketStream stream,
927 SilcPacketType type, SilcPacketFlags flags, ...);
929 /****f* silccore/SilcPacketAPI/silc_packet_send_va_ext
934 * silc_packet_send_va_ext(SilcPacketStream stream,
935 * SilcPacketType type, SilcPacketFlags flags,
936 * SilcIdType src_id_type, void *srd_id,
937 * SilcIdType dst_id_type, void *dst_id,
938 * SilcCipher cipher, SilcHmac hmac, ...);
942 * Same as silc_packet_send_va but with this function different sending
943 * parameters can be sent as argument. This function can be used to
944 * set specific IDs, cipher and HMAC to be used in packet sending,
945 * instead of the ones saved in the `stream'. If any of the extra
946 * pointers are NULL, default values set to the stream will apply.
949 SilcBool silc_packet_send_va_ext(SilcPacketStream stream,
950 SilcPacketType type, SilcPacketFlags flags,
951 SilcIdType src_id_type, void *src_id,
952 SilcIdType dst_id_type, void *dst_id,
953 SilcCipher cipher, SilcHmac hmac, ...);
955 /****f* silccore/SilcPacketAPI/silc_packet_wait
959 * void *silc_packet_wait_init(SilcPacketStream stream, ...);
963 * Initializes a packet waiter for the packet stream `stream' and
964 * for the variable argument list of packet types. The function
965 * silc_packet_wait can be used to block the thread until a packet
966 * has been received. This function is used to initialize the waiting
967 * and to give the list of packet types that caller wish to receive.
968 * The variable argument list must end with -1. To receive all
969 * packets use SILC_PACKET_ANY. Returns a context that must be given
970 * to the silc_packet_wait function as argument. Returns NULL on
971 * error. To uninitialize the waiting call silc_packet_wait_uninit.
975 * Note that packets may be available immediately after calling this
976 * function and they will be buffered, until silc_packet_wait is called.
982 * // Will wait for private message packets
983 * waiter = silc_packet_wait_init(stream,
984 * SILC_PACKET_PRIVATE_MESSAGE, -1);
988 void *silc_packet_wait_init(SilcPacketStream stream, ...);
990 /****f* silccore/SilcPacketAPI/silc_packet_wait
994 * void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
998 * Uninitializes the waiting context. This may be called also from
999 * another thread while other thread is waiting for packets. This will
1000 * inform the waiting thread to stop waiting.
1003 void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1005 /****f* silccore/SilcPacketAPI/silc_packet_wait
1009 * int silc_packet_wait(void *waiter, int timeout,
1010 * SilcPacket *return_packet)
1014 * A special function that can be used to wait for a packet to arrive.
1015 * This function will block the calling process or thread until either
1016 * a packet is received into the `return_packet' pointer or the specified
1017 * timeout value `timeout', which is in milliseconds, will expire. If
1018 * the timeout is 0, no timeout exist. Before calling this function the
1019 * silc_packet_wait_init must be called. The caller is responsible for
1020 * freeing the returned packet with silc_packet_free.
1022 * This function can be used for example from a thread that wants to
1023 * block until SILC packet has been received.
1025 * Returns 1 when packet was received, 0 if timeout occurred and -1 if
1030 * static int foo_read_data(FooContext c)
1032 * SilcPacket packet;
1036 * // Will wait for private message packets
1037 * if (c->initialized == FALSE) {
1038 * waiter = silc_packet_wait_init(stream,
1039 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1040 * c->initialized = TRUE;
1044 * // Wait here until private message packet is received
1045 * if ((silc_packet_wait(waiter, 0, &packet)) < 0)
1048 * ... process packet ...
1054 int silc_packet_wait(void *waiter, int timeout, SilcPacket *return_packet);
1056 /****f* silccore/SilcPacketAPI/silc_packet_free
1060 * void silc_packet_free(SilcPacket packet);
1064 * This function is used to free the SilcPacket pointer that application
1065 * receives in the SilcPacketReceive callback. Application must free
1066 * the packet if it takes it in to processing.
1069 void silc_packet_free(SilcPacket packet);
1071 #endif /* SILCPACKET_H */