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/SILC Packet Engine 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.
201 * You may retrieve string version of the SilcPacketError by calling
202 * silc_packet_error_string.
207 SILC_PACKET_ERR_READ, /* Error while reading */
208 SILC_PACKET_ERR_WRITE, /* Error while writing */
209 SILC_PACKET_ERR_MAC_FAILED, /* Packet MAC check failed */
210 SILC_PACKET_ERR_DECRYPTION_FAILED, /* Packet decryption failed */
211 SILC_PACKET_ERR_UNKNOWN_SID, /* Unknown SID (with IV included) */
212 SILC_PACKET_ERR_MALFORMED, /* Packet is malformed */
213 SILC_PACKET_ERR_NO_MEMORY, /* System out of memory */
217 /****f* silccore/SilcPacketAPI/SilcPacketReceiveCb
221 * typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
222 * SilcPacketStream stream,
224 * void *callback_context,
225 * void *stream_context);
229 * The packet receive callback is called by the packet engine when a new
230 * SILC Packet has arrived. The application must free the returned
231 * SilcPacket with silc_packet_free if it takes the packet in for
232 * processing. This callback is set in the SilcPacketCallbacks structure.
233 * The `callback_context' is the context set as argument in the
234 * silc_packet_engine_start function. The `stream_context' is stream
235 * specific context that was set by calling silc_packet_set_context.
237 * If the application takes the received packet `packet' into processing
238 * TRUE must be returned. If FALSE is returned the packet engine will
239 * pass the packet to other packet processor, if one has been linked
240 * to the stream with silc_packet_stream_link function. If no extra
241 * processor is linked the packet is dropped.
246 * silc_foo_packet_receive_cb(SilcPacketEngine engine,
247 * SilcPacketStream stream, SilcPacket packet,
248 * void *callback_context, void *stream_context)
250 * Application ctx = callback_context;
252 * // If we're not up yet, let's not process the packet
253 * if (ctx->initialized == FALSE)
256 * // Process the incoming packet...
259 * // It's our packet now, no one else will get it
264 typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
265 SilcPacketStream stream,
267 void *callback_context,
268 void *stream_context);
270 /****f* silccore/SilcPacketAPI/SilcPacketEosCb
274 * typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
275 * SilcPacketStream stream,
276 * void *callback_context,
277 * void *stream_context);
281 * The End Of Stream (EOS) callback, that is called by the packet engine
282 * when the underlaying stream has ended. No more data can be sent to
283 * the stream or read from it. The `stream' must be destroyed by
284 * calling the silc_packet_stream_destroy. This callback is set in the
285 * SilcPacketCallbacks structure.
288 typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
289 SilcPacketStream stream,
290 void *callback_context,
291 void *stream_context);
293 /****f* silccore/SilcPacketAPI/SilcPacketErrorCb
297 * typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
298 * SilcPacketStream stream,
299 * SilcPacketError error,
300 * void *callback_context,
301 * void *stream_context);
305 * The error callback that is called by the packet engine if an error
306 * occurs. The `error' will indicate the error. This callback is set
307 * in the SilcPacketCallbacks structure.
310 typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
311 SilcPacketStream stream,
312 SilcPacketError error,
313 void *callback_context,
314 void *stream_context);
316 /****s* silccore/SilcPacketAPI/SilcPacketCallbacks
320 * typedef struct { ... } *SilcPacketCallbacks;
324 * This structure is sent as argument to the silc_packet_engine_start
325 * function to set the callback functions for the packet engine. The
326 * packet engine will call the callbacks when necessary. Application
327 * must always be provided for the packet engine.
332 SilcPacketReceiveCb packet_receive; /* Called when packet is received */
333 SilcPacketEosCb eos; /* Called on end of stream */
334 SilcPacketErrorCb error; /* Called on an error */
335 } SilcPacketCallbacks;
340 /****f* silccore/SilcPacketAPI/silc_packet_engine_start
345 * silc_packet_engine_start(SilcRng rng, SilcBool router,
346 * SilcPacketCallbacks *callbacks,
347 * void *callback_context);
351 * Create new packet engine for processing incoming and outgoing packets.
352 * If `router' is TRUE then the application is considered to be router
353 * server, and certain packets are handled differently. Client and normal
354 * server must set it to FALSE. The `callbacks' is a SilcPacketCallbacks
355 * structure provided by the caller which includes the callbacks that is
356 * called when for example packet is received, or end of stream is called.
360 * The packet engine is thread safe. You can use one packet engine in
361 * multi threaded application.
365 silc_packet_engine_start(SilcRng rng, SilcBool router,
366 SilcPacketCallbacks *callbacks,
367 void *callback_context);
369 /****f* silccore/SilcPacketAPI/silc_packet_engine_stop
373 * void silc_packet_engine_stop(SilcPacketEngine engine);
377 * Stop the packet engine. No new packets can be sent or received after
378 * calling this, and the `engine' will become invalid.
381 void silc_packet_engine_stop(SilcPacketEngine engine);
383 /****f* silccore/SilcPacketAPI/silc_packet_error_string
387 * const char *silc_packet_error_string(SilcPacketError error);
391 * Return the packet error as string.
394 const char *silc_packet_error_string(SilcPacketError error);
396 /****f* silccore/SilcPacketAPI/silc_packet_engine_get_streams
400 * SilcDList silc_packet_engine_get_streams(SilcPacketEngine engine);
404 * Returns list of packet streams added to the packet engine. The caller
405 * must free the list with silc_dlist_uninit.
408 SilcDList silc_packet_engine_get_streams(SilcPacketEngine engine);
410 /****f* silccore/SilcPacketAPI/silc_packet_stream_create
414 * SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
415 * SilcSchedule schedule,
416 * SilcStream stream);
420 * Create new packet stream and use the `stream' as underlaying stream.
421 * Usually the `stream' would be a socket stream, but it can be any
422 * stream. After this function returns, packets can immediately be
423 * sent to and received from the stream.
427 * SilcPacketStream cannot be used with silc_stream_* routines (such as
428 * silc_stream_read and silc_stream_write) because of its special nature.
429 * Use the silc_packet_send and the silc_packet_send_ext to send packets.
430 * To read packets you will receive the packet receive callback from
431 * packet engine. Destroy the stream with silc_packet_stream_destroy.
433 * The SilcPacketStream is thread safe. Same context can be safely used
434 * in multi threaded environment.
437 SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
438 SilcSchedule schedule,
441 /****f* silccore/SilcPacketAPI/silc_packet_stream_add_remote
445 * SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
446 * const char *remote_ip,
447 * SilcUInt16 remote_port,
448 * SilcPacket packet);
452 * This function is used to add remote receivers in packet stream `stream'
453 * that has UDP/IP socket stream as the underlaying stream. This function
454 * cannot be used with other type of streams. This returns new packet
455 * stream context that can be used to send to and receive packets from
456 * the specified remote IP and remote port, or NULL on error. The `stream'
457 * is the actual stream that is used to send and receive the data.
459 * When the parent `stream' receives packets from remote IP address
460 * and port that does not have its own remote packet stream, it returns
461 * the packet to the packet callback set for `stream'. The sender's
462 * IP address and port can then be retrieved by using the
463 * silc_packet_get_sender function and to create new packet stream by
464 * calling this function. After that, all packets from that IP address
465 * and port will be received by the new packet stream.
467 * If the `packet' is non-NULL it will be injected into the new packet
468 * stream as soon as the scheduler associated with `stream' schedules
469 * new tasks. It can be used to inject an incoming packet to the stream.
471 * This interface is for connectionless UDP streams. If it is possible
472 * to create connected stream it should be done for performance reasons.
476 * // Create parent packet stream, it can receive packets from anywhere
477 * listener = silc_net_udp_connect("0.0.0.0", 500, NULL, 0, schedule);
478 * parent = silc_packet_stream_create(engine, schedule, listener);
481 * // Received a packet to the parent stream, get the sender information.
482 * silc_packet_get_sender(packet, &ip, &port);
484 * // Create new packet stream for this remote location.
485 * remote = silc_packet_stream_add_remote(parent, ip, port, packet);
488 SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
489 const char *remote_ip,
490 SilcUInt16 remote_port,
493 /****f* silccore/SilcPacketAPI/silc_packet_stream_destroy
497 * void silc_packet_stream_destroy(SilcPacketStream stream);
501 * Destroy packet stream and the underlaying stream. This will also
502 * close and destroy the underlaying stream.
505 void silc_packet_stream_destroy(SilcPacketStream stream);
507 /****f* silccore/SilcPacketAPI/silc_packet_stream_is_valid
511 * SilcBool silc_packet_stream_is_valid(SilcPacketStream stream);
515 * Returns TRUE if the packet stream indicated by `stream' is valid and
516 * has not been disconnected or destroyed.
519 SilcBool silc_packet_stream_is_valid(SilcPacketStream stream);
521 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_router
525 * void silc_packet_stream_set_router(SilcPacketStream stream);
529 * When called sets the stream indicates by `stream' as SILC router
530 * connection stream. This causes that certain packets are handled
531 * differently. This must be called for router connection streams and
532 * must not be called for any other stream.
535 void silc_packet_stream_set_router(SilcPacketStream stream);
537 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_iv_included
541 * void silc_packet_stream_set_iv_included(SilcPacketStream stream);
545 * Sets an IV Included property for the stream indicated by `stream'.
546 * This means that the IV used in the encryption will be included in
547 * the resulted ciphertext. This makes it possible to send and receive
548 * packets on unreliable network transport protocol, such as UDP/IP.
549 * This must be called if the underlaying stream in the `stream' is UDP
552 * When this is set to the stream the silc_packet_set_sid must be called
553 * to set new Security ID. The Security ID will be included with the IV
557 void silc_packet_stream_set_iv_included(SilcPacketStream stream);
559 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_stream
563 * void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
564 * SilcStream stream);
568 * This function may be used to change the underlaying stream in the
569 * packet stream indicated by `packet_stream'. Note that the old
570 * stream will not be used after calling this function. The caller is
571 * responsible destroying the old stream. The `stream' will use
572 * the same scheduler as the `packet_stream'.
575 void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
578 /****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
582 * SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
586 * Returns the actual stream that is associated with the packet stream
587 * `stream'. The caller must not free the returned stream. The returned
588 * stream is the same pointer that was set for silc_packet_stream_create.
589 * This function could be used for example when an error callback is
590 * called by the packet engine to retrieve the actual lower level error
594 SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
596 /****f* silccore/SilcPacketAPI/silc_packet_stream_link
600 * SilcBool silc_packet_stream_link(SilcPacketStream stream,
601 * SilcPacketCallbacks *callbacks,
602 * void *callback_context,
603 * int priority, ...);
607 * Links the packet processing callbacks indicated by `callbacks' into
608 * the packet stream indicated by `stream' with priority `priority' for
609 * the packet types given in the variable argument list. This function
610 * can be used to link to the packet stream for specific packet types
611 * and receive them in the specified callbacks. This way, a third party,
612 * for example some library may attach itself into the packet stream
613 * and receive and process certain packets. The variable argument
614 * list is ended with -1. To link to receive all packets use
617 * The default packet processing callbacks given as argument to the
618 * silc_packet_engine_start has the priority 0. Any priority higher
619 * than 0 will then take precedence over the default callbacks. Any
620 * priority lower than 0 (negative value) will be processed after the
623 * Note that setting only the 'packet_receive' callback in the `callbacks'
628 * // Link to this packet stream, with high priority, for
629 * // SILC_PACKET_CONNECTION_AUTH and SILC_PACKET_CONNECTION_AUTH_REQUEST
630 * // packets. We don't care about other packets.
631 * silc_packet_stream_link(stream, our_callbacks, our_context,
632 * 1000000, SILC_PACKET_CONNECTION_AUTH,
633 * SILC_PACKET_CONNECTION_AUTH_REQUEST, -1);
636 SilcBool silc_packet_stream_link(SilcPacketStream stream,
637 SilcPacketCallbacks *callbacks,
638 void *callback_context,
641 /****f* silccore/SilcPacketAPI/silc_packet_stream_unlink
645 * void silc_packet_stream_unlink(SilcPacketStream stream,
646 * SilcPacketCallbacks *callbacks,
647 * void *callback_context);
651 * Unlinks the `callbacks' with `callback_context' from the packet stream
652 * indicated by `stream'. This function must be called for the callbacks
653 * that was linked to `stream' when they are not needed anymore.
656 void silc_packet_stream_unlink(SilcPacketStream stream,
657 SilcPacketCallbacks *callbacks,
658 void *callback_context);
660 /****f* silccore/SilcPacketAPI/SilcPacketWrapCoder
664 * typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
665 * SilcStreamStatus status,
671 * The encoder/decoder callback for silc_packet_stream_wrap. If the
672 * `status' is SILC_STREAM_CAN_WRITE then additional data can be added
673 * to `buffer'. It is added before the data that is written with
674 * silc_stream_write. The silc_buffer_enlarge should be called to verify
675 * there is enough room in `buffer' before adding data to it. The `buffer'
678 * If the `status' is SILC_STREAM_CAN_READ then data from the `buffer'
679 * may be read before it is passed to readed when silc_stream_read is
680 * called. The `buffer' may be advanced also to hide data in it.
682 * This function returns FALSE in case of error.
685 typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
686 SilcStreamStatus status,
690 /****f* silccore/SilcPacketAPI/silc_packet_stream_wrap
694 * SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
695 * SilcPacketType type,
696 * SilcPacketFlags flags,
697 * SilcBool blocking_mode,
698 * SilcPacketWrapCoder coder,
703 * Wraps the packet stream indicated by `stream' into a SilcStream for
704 * the packet type indicated by `type' with packet flags indicated by
705 * `flags'. The returned SilcStream can be used to read and write the
706 * specified SILC packets with the specified packet flags, by calling
707 * silc_stream_read and silc_stream_write, respectively. The returned
708 * stream can be destroyed by calling silc_stream_destroy. It does not
709 * destroy the wrapped packet stream.
711 * If the `blocking_mode' mode is TRUE then the silc_stream_read and
712 * silc_stream_write may block the calling process or thread until SILC
713 * packet is read or written. If it is FALSE the stream is in non-blocking
714 * mode and the calls never block. The returned stream is thread-safe and
715 * packets may be read and written in multi-threaded environment.
717 * In non-blocking mode the silc_stream_set_notifier must be called before
718 * the returned stream can be used to read packets. The stream status
719 * SILC_STREAM_CAN_READ will be returned to the notifier callback to
720 * indicate that a packet is ready for reading. Calling silc_stream_read
721 * once returns one complete SILC packet data payload (which is of type of
724 * The `coder' is optional encoder/decoder callback which the packet engine
725 * will call if it is non-NULL. It can be used to encode additional data
726 * into each packet when silc_stream_write is called or decode data before
727 * it is passed to reader when silc_stream_read is called. The `context'
728 * is passed to `coder'.
730 * The returned SilcStream can be used as any normal stream and all
731 * SilcStream API functions may be used with the stream. This returns
735 SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
737 SilcPacketFlags flags,
738 SilcBool blocking_mode,
739 SilcPacketWrapCoder coder,
742 /****f* silccore/SilcPacketAPI/silc_packet_stream_is_udp
746 * SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
750 * Returns TRUE if the packet stream indicated by `stream' is using
754 SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
756 /****f* silccore/SilcPacketAPI/silc_packet_get_sender
760 * SilcBool silc_packet_get_sender(SilcPacket packet,
761 * const char **sender_ip,
762 * SilcUInt16 *sender_port);
766 * Returns the packet sender's IP address and port from UDP packet
767 * indicated by `packet'. This can be called only from the packet
768 * callback to retrieve the information of the packet's sender. Returns
769 * FALSE if the information is not available.
772 SilcBool silc_packet_get_sender(SilcPacket packet,
773 const char **sender_ip,
774 SilcUInt16 *sender_port);
776 /****f* silccore/SilcPacketAPI/silc_packet_stream_ref
780 * void silc_packet_stream_ref(SilcPacketStream stream);
784 * Increase reference counter for the stream indicated by `stream'. This
785 * can be used to take a reference for the stream. To unreference the
786 * stream call silc_packet_stream_unref function.
789 void silc_packet_stream_ref(SilcPacketStream stream);
791 /****f* silccore/SilcPacketAPI/silc_packet_stream_unref
795 * void silc_packet_stream_unref(SilcPacketStream stream);
799 * Decrease reference counter for the stream indicated by `stream'. If
800 * the counter hits zero the stream will be destroyed automatically.
803 void silc_packet_stream_unref(SilcPacketStream stream);
805 /****f* silccore/SilcPacketAPI/silc_packet_get_engine
809 * SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
813 * Returns the packet engine from the `stream'.
816 SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
818 /****f* silccore/SilcPacketAPI/silc_packet_set_context
822 * void silc_packet_set_context(SilcPacketStream stream,
823 * void *stream_context);
827 * Sets a stream specific context to the stream. The context will
828 * be delivered to all callback functions, and it can be retrieved by
829 * calling silc_packet_get_context function as well. Note that this is
830 * separate packet stream specific context, and not the same as
831 * `callback_context' in silc_packet_engine_start. Both will be delivered
832 * to the callbacks, and this context as the `stream_context' argument.
835 void silc_packet_set_context(SilcPacketStream stream, void *stream_context);
837 /****f* silccore/SilcPacketAPI/silc_packet_get_context
841 * void *silc_packet_get_context(SilcPacketStream stream);
845 * Returns the current set application context, or NULL if none is set.
848 void *silc_packet_get_context(SilcPacketStream stream);
850 /****f* silccore/SilcPacketAPI/silc_packet_set_keys
854 * void silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
855 * SilcCipher receive_key, SilcHmac send_hmac,
856 * SilcHmac receive_hmac, SilcBool rekey);
860 * Set ciphers and HMACs to be used to encrypt sent packets, and decrypt
861 * received packets. This can be called multiple times to change the
864 * If the `rekey' is TRUE this function will send SILC_PACKET_REKEY_DONE
865 * to the `stream' and will set the new keys. If it is FALSE the keys
866 * are changed but the packet is not changed.
868 * When changing keys the old cipher and HMACs will be freed. If the keys
869 * are not set at all, packets will not be encrypted or decrypted.
872 SilcBool silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
873 SilcCipher receive_key, SilcHmac send_hmac,
874 SilcHmac receive_hmac, SilcBool rekey);
876 /****f* silccore/SilcPacketAPI/silc_packet_get_keys
880 * SilcBool silc_packet_get_keys(SilcPacketStream stream,
881 * SilcCipher *send_key,
882 * SilcCipher *receive_key,
883 * SilcHmac *send_hmac,
884 * SilcHmac *receive_hmac);
888 * Returns the pointers of current ciphers and HMACs from the `stream'.
889 * Returns FALSE if keys are not set.
892 SilcBool silc_packet_get_keys(SilcPacketStream stream,
893 SilcCipher *send_key, SilcCipher *receive_key,
894 SilcHmac *send_hmac, SilcHmac *receive_hmac);
896 /****f* silccore/SilcPacketAPI/silc_packet_set_ids
900 * SilcBool silc_packet_set_ids(SilcPacketStream stream,
901 * SilcIdType src_id_type, const void *src_id
902 * SilcIdType dst_id_type, const void *dst_id);
906 * Set the source ID and destination ID to be used when sending packets to
907 * this packet stream. The IDs to be used for a packet stream can be
908 * overridden when sending packets. However, if the IDs do not ever change
909 * for the packet stream it is recommended they are set using this function.
910 * In this case they can be omitted when sending packets to the stream.
911 * It is also possible to set only source or destination ID.
914 SilcBool silc_packet_set_ids(SilcPacketStream stream,
915 SilcIdType src_id_type, const void *src_id,
916 SilcIdType dst_id_type, const void *dst_id);
918 /****f* silccore/SilcPacketAPI/silc_packet_set_ids
922 * SilcBool silc_packet_get_ids(SilcPacketStream stream,
923 * SilcBool *src_id_set, SilcID *src_id,
924 * SilcBool *dst_id_set, SilcID *dst_id);
928 * Returns source and destination IDs from the packet stream. The
929 * `src_id_set' is set to TRUE if the source ID was returned. The
930 * `dst_id_set' is set to TRUE if the destination ID was returned.
933 SilcBool silc_packet_get_ids(SilcPacketStream stream,
934 SilcBool *src_id_set, SilcID *src_id,
935 SilcBool *dst_id_set, SilcID *dst_id);
937 /****f* silccore/SilcPacketAPI/silc_packet_set_sid
941 * SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
945 * Sets new Security ID to the packet stream indicated by `stream'. This
946 * is called only if the IV Included property was set to the stream
947 * by calling silc_packet_stream_set_iv_included. This function sets
948 * new Security ID to the stream which is then included in the ciphertext
949 * of a packet. The `sid' must be 0 when it is set for the very first
950 * time and must be increased by one after each rekey. This function must
951 * be called every time new keys are added to the stream after a rekey.
953 * If this function is called when the IV Included property has not been
954 * set to the stream the `sid' will be ignored. Returns FALSE if the
955 * IV Included has not been set, TRUE otherwise.
958 SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
960 /****f* silccore/SilcPacketAPI/silc_packet_send
964 * SilcBool silc_packet_send(SilcPacketStream stream,
965 * SilcPacketType type, SilcPacketFlags flags,
966 * const unsigned char *data,
967 * SilcUInt32 data_len);
971 * Send `data' of length of `data_len' to the packet stream indicated by
972 * `stream'. If ciphers and HMACs were set using silc_packet_set_keys
973 * the packet will be encrypted and MAC will be computed for it. If
974 * silc_packet_set_ids was used to set source and destination ID for the
975 * packet stream those IDs are used in the packet. If IDs have not been
976 * set and they need to be provided then silc_packet_send_ext function
977 * should be used. Otherwise, the packet will not have IDs set at all.
978 * Returns FALSE if packet could not be sent.
981 SilcBool silc_packet_send(SilcPacketStream stream,
982 SilcPacketType type, SilcPacketFlags flags,
983 const unsigned char *data, SilcUInt32 data_len);
985 /****f* silccore/SilcPacketAPI/silc_packet_send_ext
990 * silc_packet_send_ext(SilcPacketStream stream,
991 * SilcPacketType type, SilcPacketFlags flags,
992 * SilcIdType src_id_type, void *srd_id,
993 * SilcIdType dst_id_type, void *dst_id,
994 * const unsigned char *data, SilcUInt32 data_len,
995 * SilcCipher cipher, SilcHmac hmac);
999 * Same as silc_packet_send but with this function different sending
1000 * parameters can be sent as argument. This function can be used to
1001 * set specific IDs, cipher and HMAC to be used in packet sending,
1002 * instead of the ones saved in the `stream'. If any of the extra
1003 * pointers are NULL, default values set to the stream will apply.
1006 SilcBool silc_packet_send_ext(SilcPacketStream stream,
1007 SilcPacketType type, SilcPacketFlags flags,
1008 SilcIdType src_id_type, void *src_id,
1009 SilcIdType dst_id_type, void *dst_id,
1010 const unsigned char *data, SilcUInt32 data_len,
1011 SilcCipher cipher, SilcHmac hmac);
1013 /****f* silccore/SilcPacketAPI/silc_packet_send_va
1017 * SilcBool silc_packet_send_va(SilcPacketStream stream,
1018 * SilcPacketType type,
1019 * SilcPacketFlags flags, ...);
1023 * Same as silc_packet_send but takes the data in as variable argument
1024 * formatted buffer (see silcbuffmt.h). The arguments must be ended
1025 * with SILC_STR_END. Returns FALSE if packet could not be sent or
1026 * the buffer could not be formatted.
1030 * // Send NEW_CLIENT packet
1031 * silc_packet_send_va(stream, SILC_PACKET_NEW_CLIENT, 0,
1032 * SILC_STR_UI_SHORT(username_len),
1033 * SILC_STR_DATA(username, username_len),
1034 * SILC_STR_UI_SHORT(realname_len),
1035 * SILC_STR_DATA(realname, realname_len),
1039 SilcBool silc_packet_send_va(SilcPacketStream stream,
1040 SilcPacketType type, SilcPacketFlags flags, ...);
1042 /****f* silccore/SilcPacketAPI/silc_packet_send_va_ext
1047 * silc_packet_send_va_ext(SilcPacketStream stream,
1048 * SilcPacketType type, SilcPacketFlags flags,
1049 * SilcIdType src_id_type, void *srd_id,
1050 * SilcIdType dst_id_type, void *dst_id,
1051 * SilcCipher cipher, SilcHmac hmac, ...);
1055 * Same as silc_packet_send_va but with this function different sending
1056 * parameters can be sent as argument. This function can be used to
1057 * set specific IDs, cipher and HMAC to be used in packet sending,
1058 * instead of the ones saved in the `stream'. If any of the extra
1059 * pointers are NULL, default values set to the stream will apply.
1062 SilcBool silc_packet_send_va_ext(SilcPacketStream stream,
1063 SilcPacketType type, SilcPacketFlags flags,
1064 SilcIdType src_id_type, void *src_id,
1065 SilcIdType dst_id_type, void *dst_id,
1066 SilcCipher cipher, SilcHmac hmac, ...);
1068 /****f* silccore/SilcPacketAPI/silc_packet_wait
1072 * void *silc_packet_wait_init(SilcPacketStream stream, ...);
1076 * Initializes a packet waiter for the packet stream `stream' and
1077 * for the variable argument list of packet types. The function
1078 * silc_packet_wait can be used to block the thread until a packet
1079 * has been received. This function is used to initialize the waiting
1080 * and to give the list of packet types that caller wish to receive.
1081 * The variable argument list must end with -1. To receive all
1082 * packets use SILC_PACKET_ANY. Returns a context that must be given
1083 * to the silc_packet_wait function as argument. Returns NULL on
1084 * error. To uninitialize the waiting call silc_packet_wait_uninit.
1088 * Note that packets may be available immediately after calling this
1089 * function and they will be buffered, until silc_packet_wait is called.
1095 * // Will wait for private message packets
1096 * waiter = silc_packet_wait_init(stream,
1097 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1101 void *silc_packet_wait_init(SilcPacketStream stream, ...);
1103 /****f* silccore/SilcPacketAPI/silc_packet_wait_uninit
1107 * void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1111 * Uninitializes the waiting context. This may be called also from
1112 * another thread while other thread is waiting for packets. This will
1113 * inform the waiting thread to stop waiting.
1116 void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1118 /****f* silccore/SilcPacketAPI/silc_packet_wait
1122 * int silc_packet_wait(void *waiter, int timeout,
1123 * SilcPacket *return_packet)
1127 * A special function that can be used to wait for a packet to arrive.
1128 * This function will block the calling process or thread until either
1129 * a packet is received into the `return_packet' pointer or the specified
1130 * timeout value `timeout', which is in milliseconds, will expire. If
1131 * the timeout is 0, no timeout exist. Before calling this function the
1132 * silc_packet_wait_init must be called. The caller is responsible for
1133 * freeing the returned packet with silc_packet_free.
1135 * This function can be used for example from a thread that wants to
1136 * block until SILC packet has been received.
1138 * Returns 1 when packet was received, 0 if timeout occurred and -1 if
1143 * static int foo_read_data(FooContext c)
1145 * SilcPacket packet;
1149 * // Will wait for private message packets
1150 * if (c->initialized == FALSE) {
1151 * waiter = silc_packet_wait_init(stream,
1152 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1153 * c->initialized = TRUE;
1157 * // Wait here until private message packet is received
1158 * if ((silc_packet_wait(waiter, 0, &packet)) < 0)
1161 * ... process packet ...
1167 int silc_packet_wait(void *waiter, int timeout, SilcPacket *return_packet);
1169 /****f* silccore/SilcPacketAPI/silc_packet_free
1173 * void silc_packet_free(SilcPacket packet);
1177 * This function is used to free the SilcPacket pointer that application
1178 * receives in the SilcPacketReceive callback. Application must free
1179 * the packet if it takes it in to processing.
1182 void silc_packet_free(SilcPacket packet);
1184 #endif /* SILCPACKET_H */