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 /* Maximum packet length */
38 #define SILC_PACKET_MAX_LEN 0xffff
40 /* Maximum length of ID */
41 #define SILC_PACKET_MAX_ID_LEN 28
43 /****d* silccore/SilcPacketAPI/SilcPacketType
47 * typedef SilcUInt8 SilcPacketType;
51 * SILC packet type definition and all the packet types.
55 typedef SilcUInt8 SilcPacketType;
57 /* SILC Packet types. */
58 #define SILC_PACKET_DISCONNECT 1 /* Disconnection */
59 #define SILC_PACKET_SUCCESS 2 /* Success */
60 #define SILC_PACKET_FAILURE 3 /* Failure */
61 #define SILC_PACKET_REJECT 4 /* Rejected */
62 #define SILC_PACKET_NOTIFY 5 /* Notify message */
63 #define SILC_PACKET_ERROR 6 /* Error message */
64 #define SILC_PACKET_CHANNEL_MESSAGE 7 /* Message for channel */
65 #define SILC_PACKET_CHANNEL_KEY 8 /* Key of the channel */
66 #define SILC_PACKET_PRIVATE_MESSAGE 9 /* Private message */
67 #define SILC_PACKET_PRIVATE_MESSAGE_KEY 10 /* Private message key*/
68 #define SILC_PACKET_COMMAND 11 /* Command */
69 #define SILC_PACKET_COMMAND_REPLY 12 /* Reply to a command */
70 #define SILC_PACKET_KEY_EXCHANGE 13 /* Start of KE */
71 #define SILC_PACKET_KEY_EXCHANGE_1 14 /* KE1 */
72 #define SILC_PACKET_KEY_EXCHANGE_2 15 /* KE2 */
73 #define SILC_PACKET_CONNECTION_AUTH_REQUEST 16 /* Request of auth meth */
74 #define SILC_PACKET_CONNECTION_AUTH 17 /* Connectinon auth */
75 #define SILC_PACKET_NEW_ID 18 /* Sending new ID */
76 #define SILC_PACKET_NEW_CLIENT 19 /* Client registering */
77 #define SILC_PACKET_NEW_SERVER 20 /* Server registering */
78 #define SILC_PACKET_NEW_CHANNEL 21 /* Channel registering */
79 #define SILC_PACKET_REKEY 22 /* Re-key start */
80 #define SILC_PACKET_REKEY_DONE 23 /* Re-key done */
81 #define SILC_PACKET_HEARTBEAT 24 /* Heartbeat */
82 #define SILC_PACKET_KEY_AGREEMENT 25 /* Key Agreement request */
83 #define SILC_PACKET_RESUME_ROUTER 26 /* Backup router resume */
84 #define SILC_PACKET_FTP 27 /* File Transfer */
85 #define SILC_PACKET_RESUME_CLIENT 28 /* Client resume */
86 #define SILC_PACKET_ACK 29 /* Acknowledgement */
88 #define SILC_PACKET_PRIVATE 200 /* Private range start */
89 #define SILC_PACKET_MAX 255 /* RESERVED */
91 #define SILC_PACKET_NONE 0 /* RESERVED */
92 #define SILC_PACKET_ANY 0
95 /****d* silccore/SilcPacketAPI/SilcPacketFlags
99 * typedef SilcUInt8 SilcPacketFlags;
103 * SILC packet flags type definition and all the packet flags.
107 typedef SilcUInt8 SilcPacketFlags;
109 /* All defined packet flags */
110 #define SILC_PACKET_FLAG_NONE 0x00 /* No flags */
111 #define SILC_PACKET_FLAG_PRIVMSG_KEY 0x01 /* Private message key */
112 #define SILC_PACKET_FLAG_LIST 0x02 /* Packet is a list */
113 #define SILC_PACKET_FLAG_BROADCAST 0x04 /* Packet is a broadcast */
114 #define SILC_PACKET_FLAG_COMPRESSED 0x08 /* Payload is compressed */
115 #define SILC_PACKET_FLAG_ACK 0x10 /* Acknowledge packet */
117 /* Impelemntation specific flags */
118 #define SILC_PACKET_FLAG_LONG_PAD 0x12 /* Use maximum padding */
121 /****s* silccore/SilcPacketAPI/SilcPacketEngine
125 * typedef struct SilcPacketEngineStruct *SilcPacketEngine;
129 * The packet engine context, allocated by silc_packet_engine_start.
130 * The engine is destroyed with silc_packet_engine_stop.
133 typedef struct SilcPacketEngineStruct *SilcPacketEngine;
135 /****s* silccore/SilcPacketAPI/SilcPacketStream
139 * typedef struct SilcPacketStreamStruct *SilcPacketStream;
143 * The packet stream context, allocated by silc_packet_stream_create.
144 * The stream is destroyed with silc_packet_stream_destroy.
147 typedef struct SilcPacketStreamStruct *SilcPacketStream;
149 /****s* silccore/SilcPacketAPI/SilcPacket
153 * typedef struct SilcPacketStruct *SilcPacket;
157 * The SilcPacket is returned by the packet engine in the SilcPacketReceive
158 * callback. The application can parse the data payload from the
159 * SilcPacket. Also packet type, flags, and sender and destination
160 * IDs are available. The application must free the packet with the
161 * silc_packet_free function if it takes it in for processing.
163 * The `buffer' field contains the parsed packet payload and the start
164 * of the data area will point to the start of the packet payload.
166 * The list pointer `next' can be used by the application to put the
167 * packet context in a list during processing, if needed.
171 typedef struct SilcPacketStruct {
172 struct SilcPacketStruct *next; /* List pointer, application may set */
173 SilcPacketStream stream; /* Packet stream this packet is from */
174 SilcBufferStruct buffer; /* Packet data payload */
175 unsigned char *src_id; /* Source ID */
176 unsigned char *dst_id; /* Destination ID */
177 unsigned int src_id_len : 6; /* Source ID length */
178 unsigned int src_id_type : 2; /* Source ID type */
179 unsigned int dst_id_len : 6; /* Destination ID length */
180 unsigned int dst_id_type : 2; /* Destination ID type */
181 SilcPacketType type; /* Packet type */
182 SilcPacketFlags flags; /* Packet flags */
186 /****d* silcutil/SilcPacketAPI/SilcPacketError
190 * typedef enum { ... } SilcPacketError
194 * Packet errors. This is returned in the error callback. If application
195 * needs the actual lower level stream error, it needs to retrieve it
196 * from the actual stream. It can retrieve the underlaying stream from
197 * the packet stream by calling silc_packet_stream_get_stream function.
199 * You may retrieve string version of the SilcPacketError by calling
200 * silc_packet_error_string.
205 SILC_PACKET_ERR_READ, /* Error while reading */
206 SILC_PACKET_ERR_WRITE, /* Error while writing */
207 SILC_PACKET_ERR_MAC_FAILED, /* Packet MAC check failed */
208 SILC_PACKET_ERR_DECRYPTION_FAILED, /* Packet decryption failed */
209 SILC_PACKET_ERR_UNKNOWN_SID, /* Unknown SID (with IV included) */
210 SILC_PACKET_ERR_MALFORMED, /* Packet is malformed */
211 SILC_PACKET_ERR_NO_MEMORY, /* System out of memory */
215 /****f* silccore/SilcPacketAPI/SilcPacketReceiveCb
219 * typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
220 * SilcPacketStream stream,
222 * void *callback_context,
223 * void *stream_context);
227 * The packet receive callback is called by the packet engine when a new
228 * SILC Packet has arrived. The application must free the returned
229 * SilcPacket with silc_packet_free if it takes the packet in for
230 * processing. This callback is set in the SilcPacketCallbacks structure.
231 * The `callback_context' is the context set as argument in the
232 * silc_packet_engine_start function. The `stream_context' is stream
233 * specific context that was set by calling silc_packet_set_context.
235 * If the application takes the received packet `packet' into processing
236 * TRUE must be returned. If FALSE is returned the packet engine will
237 * pass the packet to other packet processor, if one has been linked
238 * to the stream with silc_packet_stream_link function. If no extra
239 * processor is linked the packet is dropped.
244 * silc_foo_packet_receive_cb(SilcPacketEngine engine,
245 * SilcPacketStream stream, SilcPacket packet,
246 * void *callback_context, void *stream_context)
248 * Application ctx = callback_context;
250 * // If we're not up yet, let's not process the packet
251 * if (ctx->initialized == FALSE)
254 * // Process the incoming packet...
257 * // It's our packet now, no one else will get it
262 typedef SilcBool (*SilcPacketReceiveCb)(SilcPacketEngine engine,
263 SilcPacketStream stream,
265 void *callback_context,
266 void *stream_context);
268 /****f* silccore/SilcPacketAPI/SilcPacketEosCb
272 * typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
273 * SilcPacketStream stream,
274 * void *callback_context,
275 * void *stream_context);
279 * The End Of Stream (EOS) callback, that is called by the packet engine
280 * when the underlaying stream has ended. No more data can be sent to
281 * the stream or read from it. The `stream' must be destroyed by
282 * calling the silc_packet_stream_destroy. This callback is set in the
283 * SilcPacketCallbacks structure.
286 typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
287 SilcPacketStream stream,
288 void *callback_context,
289 void *stream_context);
291 /****f* silccore/SilcPacketAPI/SilcPacketErrorCb
295 * typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
296 * SilcPacketStream stream,
297 * SilcPacketError error,
298 * void *callback_context,
299 * void *stream_context);
303 * The error callback that is called by the packet engine if an error
304 * occurs. The `error' will indicate the error. This callback is set
305 * in the SilcPacketCallbacks structure.
308 typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
309 SilcPacketStream stream,
310 SilcPacketError error,
311 void *callback_context,
312 void *stream_context);
314 /****s* silccore/SilcPacketAPI/SilcPacketCallbacks
318 * typedef struct { ... } *SilcPacketCallbacks;
322 * This structure is sent as argument to the silc_packet_engine_start
323 * function to set the callback functions for the packet engine. The
324 * packet engine will call the callbacks when necessary. Application
325 * must always be provided for the packet engine.
330 SilcPacketReceiveCb packet_receive; /* Called when packet is received */
331 SilcPacketEosCb eos; /* Called on end of stream */
332 SilcPacketErrorCb error; /* Called on an error */
333 } SilcPacketCallbacks;
338 /****f* silccore/SilcPacketAPI/silc_packet_engine_start
343 * silc_packet_engine_start(SilcRng rng, SilcBool router,
344 * SilcPacketCallbacks *callbacks,
345 * void *callback_context);
349 * Create new packet engine for processing incoming and outgoing packets.
350 * If `router' is TRUE then the application is considered to be router
351 * server, and certain packets are handled differently. Client and normal
352 * server must set it to FALSE. The `callbacks' is a SilcPacketCallbacks
353 * structure provided by the caller which includes the callbacks that is
354 * called when for example packet is received, or end of stream is called.
358 * The packet engine is thread safe. You can use one packet engine in
359 * multi threaded application.
363 silc_packet_engine_start(SilcRng rng, SilcBool router,
364 SilcPacketCallbacks *callbacks,
365 void *callback_context);
367 /****f* silccore/SilcPacketAPI/silc_packet_engine_stop
371 * void silc_packet_engine_stop(SilcPacketEngine engine);
375 * Stop the packet engine. No new packets can be sent or received after
376 * calling this, and the `engine' will become invalid.
379 void silc_packet_engine_stop(SilcPacketEngine engine);
381 /****f* silccore/SilcPacketAPI/silc_packet_error_string
385 * const char *silc_packet_error_string(SilcPacketError error);
389 * Return the packet error as string.
392 const char *silc_packet_error_string(SilcPacketError error);
394 /****f* silccore/SilcPacketAPI/silc_packet_engine_get_streams
398 * SilcDList silc_packet_engine_get_streams(SilcPacketEngine engine);
402 * Returns list of packet streams added to the packet engine. The caller
403 * must free the list with silc_dlist_uninit.
406 SilcDList silc_packet_engine_get_streams(SilcPacketEngine engine);
408 /****f* silccore/SilcPacketAPI/silc_packet_stream_create
412 * SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
413 * SilcSchedule schedule,
414 * SilcStream stream);
418 * Create new packet stream and use the `stream' as underlaying stream.
419 * Usually the `stream' would be a socket stream, but it can be any
420 * stream. After this function returns, packets can immediately be
421 * sent to and received from the stream.
425 * SilcPacketStream cannot be used with silc_stream_* routines (such as
426 * silc_stream_read and silc_stream_write) because of its special nature.
427 * Use the silc_packet_send and the silc_packet_send_ext to send packets.
428 * To read packets you will receive the packet receive callback from
429 * packet engine. Destroy the stream with silc_packet_stream_destroy.
431 * The SilcPacketStream is thread safe. Same context can be safely used
432 * in multi threaded environment.
435 SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
436 SilcSchedule schedule,
439 /****f* silccore/SilcPacketAPI/silc_packet_stream_add_remote
443 * SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
444 * const char *remote_ip,
445 * SilcUInt16 remote_port,
446 * SilcPacket packet);
450 * This function is used to add remote receivers in packet stream `stream'
451 * that has UDP/IP socket stream as the underlaying stream. This function
452 * cannot be used with other type of streams. This returns new packet
453 * stream context that can be used to send to and receive packets from
454 * the specified remote IP and remote port, or NULL on error. The `stream'
455 * is the actual stream that is used to send and receive the data.
457 * When the parent `stream' receives packets from remote IP address
458 * and port that does not have its own remote packet stream, it returns
459 * the packet to the packet callback set for `stream'. The sender's
460 * IP address and port can then be retrieved by using the
461 * silc_packet_get_sender function and to create new packet stream by
462 * calling this function. After that, all packets from that IP address
463 * and port will be received by the new packet stream.
465 * If the `packet' is non-NULL it will be injected into the new packet
466 * stream as soon as the scheduler associated with `stream' schedules
467 * new tasks. It can be used to inject an incoming packet to the stream.
469 * This interface is for connectionless UDP streams. If it is possible
470 * to create connected stream it should be done for performance reasons.
474 * // Create parent packet stream, it can receive packets from anywhere
475 * listener = silc_net_udp_connect("0.0.0.0", 500, NULL, 0, schedule);
476 * parent = silc_packet_stream_create(engine, schedule, listener);
479 * // Received a packet to the parent stream, get the sender information.
480 * silc_packet_get_sender(packet, &ip, &port);
482 * // Create new packet stream for this remote location.
483 * remote = silc_packet_stream_add_remote(parent, ip, port, packet);
486 SilcPacketStream silc_packet_stream_add_remote(SilcPacketStream stream,
487 const char *remote_ip,
488 SilcUInt16 remote_port,
491 /****f* silccore/SilcPacketAPI/silc_packet_stream_destroy
495 * void silc_packet_stream_destroy(SilcPacketStream stream);
499 * Destroy packet stream and the underlaying stream. This will also
500 * close and destroy the underlaying stream.
503 void silc_packet_stream_destroy(SilcPacketStream stream);
505 /****f* silccore/SilcPacketAPI/silc_packet_stream_is_valid
509 * SilcBool silc_packet_stream_is_valid(SilcPacketStream stream);
513 * Returns TRUE if the packet stream indicated by `stream' is valid and
514 * has not been disconnected or destroyed.
517 SilcBool silc_packet_stream_is_valid(SilcPacketStream stream);
519 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_router
523 * void silc_packet_stream_set_router(SilcPacketStream stream);
527 * When called sets the stream indicates by `stream' as SILC router
528 * connection stream. This causes that certain packets are handled
529 * differently. This must be called for router connection streams and
530 * must not be called for any other stream.
533 void silc_packet_stream_set_router(SilcPacketStream stream);
535 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_iv_included
539 * void silc_packet_stream_set_iv_included(SilcPacketStream stream);
543 * Sets an IV Included property for the stream indicated by `stream'.
544 * This means that the IV used in the encryption will be included in
545 * the resulted ciphertext. This makes it possible to send and receive
546 * packets on unreliable network transport protocol, such as UDP/IP.
547 * This must be called if the underlaying stream in the `stream' is UDP
550 * When this is set to the stream the silc_packet_set_sid must be called
551 * to set new Security ID. The Security ID will be included with the IV
555 void silc_packet_stream_set_iv_included(SilcPacketStream stream);
557 /****f* silccore/SilcPacketAPI/silc_packet_stream_set_stream
561 * void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
562 * SilcStream stream);
566 * This function may be used to change the underlaying stream in the
567 * packet stream indicated by `packet_stream'. Note that the old
568 * stream will not be used after calling this function. The caller is
569 * responsible destroying the old stream. The `stream' will use
570 * the same scheduler as the `packet_stream'.
573 void silc_packet_stream_set_stream(SilcPacketStream packet_stream,
576 /****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
580 * SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
584 * Returns the actual stream that is associated with the packet stream
585 * `stream'. The caller must not free the returned stream. The returned
586 * stream is the same pointer that was set for silc_packet_stream_create.
587 * This function could be used for example when an error callback is
588 * called by the packet engine to retrieve the actual lower level error
592 SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
594 /****f* silccore/SilcPacketAPI/silc_packet_stream_link
598 * SilcBool silc_packet_stream_link(SilcPacketStream stream,
599 * SilcPacketCallbacks *callbacks,
600 * void *callback_context,
601 * int priority, ...);
605 * Links the packet processing callbacks indicated by `callbacks' into
606 * the packet stream indicated by `stream' with priority `priority' for
607 * the packet types given in the variable argument list. This function
608 * can be used to link to the packet stream for specific packet types
609 * and receive them in the specified callbacks. This way, a third party,
610 * for example some library may attach itself into the packet stream
611 * and receive and process certain packets. The variable argument
612 * list is ended with -1. To link to receive all packets use
615 * The default packet processing callbacks given as argument to the
616 * silc_packet_engine_start has the priority 0. Any priority higher
617 * than 0 will then take precedence over the default callbacks. Any
618 * priority lower than 0 (negative value) will be processed after the
621 * Note that setting only the 'packet_receive' callback in the `callbacks'
626 * // Link to this packet stream, with high priority, for
627 * // SILC_PACKET_CONNECTION_AUTH and SILC_PACKET_CONNECTION_AUTH_REQUEST
628 * // packets. We don't care about other packets.
629 * silc_packet_stream_link(stream, our_callbacks, our_context,
630 * 1000000, SILC_PACKET_CONNECTION_AUTH,
631 * SILC_PACKET_CONNECTION_AUTH_REQUEST, -1);
634 SilcBool silc_packet_stream_link(SilcPacketStream stream,
635 SilcPacketCallbacks *callbacks,
636 void *callback_context,
639 /****f* silccore/SilcPacketAPI/silc_packet_stream_unlink
643 * void silc_packet_stream_unlink(SilcPacketStream stream,
644 * SilcPacketCallbacks *callbacks,
645 * void *callback_context);
649 * Unlinks the `callbacks' with `callback_context' from the packet stream
650 * indicated by `stream'. This function must be called for the callbacks
651 * that was linked to `stream' when they are not needed anymore.
654 void silc_packet_stream_unlink(SilcPacketStream stream,
655 SilcPacketCallbacks *callbacks,
656 void *callback_context);
658 /****f* silccore/SilcPacketAPI/SilcPacketWrapCoder
662 * typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
663 * SilcStreamStatus status,
669 * The encoder/decoder callback for silc_packet_stream_wrap. If the
670 * `status' is SILC_STREAM_CAN_WRITE then additional data can be added
671 * to `buffer'. It is added before the data that is written with
672 * silc_stream_write. The silc_buffer_enlarge should be called to verify
673 * there is enough room in `buffer' before adding data to it. The `buffer'
676 * If the `status' is SILC_STREAM_CAN_READ then data from the `buffer'
677 * may be read before it is passed to readed when silc_stream_read is
678 * called. The `buffer' may be advanced also to hide data in it.
680 * This function returns FALSE in case of error.
683 typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
684 SilcStreamStatus status,
688 /****f* silccore/SilcPacketAPI/silc_packet_stream_wrap
692 * SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
693 * SilcPacketType type,
694 * SilcPacketFlags flags,
695 * SilcBool blocking_mode,
696 * SilcPacketWrapCoder coder,
701 * Wraps the packet stream indicated by `stream' into a SilcStream for
702 * the packet type indicated by `type' with packet flags indicated by
703 * `flags'. The returned SilcStream can be used to read and write the
704 * specified SILC packets with the specified packet flags, by calling
705 * silc_stream_read and silc_stream_write, respectively. The returned
706 * stream can be destroyed by calling silc_stream_destroy. It does not
707 * destroy the wrapped packet stream.
709 * If the `blocking_mode' mode is TRUE then the silc_stream_read and
710 * silc_stream_write may block the calling process or thread until SILC
711 * packet is read or written. If it is FALSE the stream is in non-blocking
712 * mode and the calls never block. The returned stream is thread-safe and
713 * packets may be read and written in multi-threaded environment.
715 * In non-blocking mode the silc_stream_set_notifier must be called before
716 * the returned stream can be used to read packets. The stream status
717 * SILC_STREAM_CAN_READ will be returned to the notifier callback to
718 * indicate that a packet is ready for reading. Calling silc_stream_read
719 * once returns one complete SILC packet data payload (which is of type of
722 * The `coder' is optional encoder/decoder callback which the packet engine
723 * will call if it is non-NULL. It can be used to encode additional data
724 * into each packet when silc_stream_write is called or decode data before
725 * it is passed to reader when silc_stream_read is called. The `context'
726 * is passed to `coder'.
728 * The returned SilcStream can be used as any normal stream and all
729 * SilcStream API functions may be used with the stream. This returns
733 SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
735 SilcPacketFlags flags,
736 SilcBool blocking_mode,
737 SilcPacketWrapCoder coder,
740 /****f* silccore/SilcPacketAPI/silc_packet_stream_is_udp
744 * SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
748 * Returns TRUE if the packet stream indicated by `stream' is using
752 SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
754 /****f* silccore/SilcPacketAPI/silc_packet_get_sender
758 * SilcBool silc_packet_get_sender(SilcPacket packet,
759 * const char **sender_ip,
760 * SilcUInt16 *sender_port);
764 * Returns the packet sender's IP address and port from UDP packet
765 * indicated by `packet'. This can be called only from the packet
766 * callback to retrieve the information of the packet's sender. Returns
767 * FALSE if the information is not available.
770 SilcBool silc_packet_get_sender(SilcPacket packet,
771 const char **sender_ip,
772 SilcUInt16 *sender_port);
774 /****f* silccore/SilcPacketAPI/silc_packet_stream_ref
778 * void silc_packet_stream_ref(SilcPacketStream stream);
782 * Increase reference counter for the stream indicated by `stream'. This
783 * can be used to take a reference for the stream. To unreference the
784 * stream call silc_packet_stream_unref function.
787 void silc_packet_stream_ref(SilcPacketStream stream);
789 /****f* silccore/SilcPacketAPI/silc_packet_stream_unref
793 * void silc_packet_stream_unref(SilcPacketStream stream);
797 * Decrease reference counter for the stream indicated by `stream'. If
798 * the counter hits zero the stream will be destroyed automatically.
801 void silc_packet_stream_unref(SilcPacketStream stream);
803 /****f* silccore/SilcPacketAPI/silc_packet_get_engine
807 * SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
811 * Returns the packet engine from the `stream'.
814 SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
816 /****f* silccore/SilcPacketAPI/silc_packet_set_context
820 * void silc_packet_set_context(SilcPacketStream stream,
821 * void *stream_context);
825 * Sets a stream specific context to the stream. The context will
826 * be delivered to all callback functions, and it can be retrieved by
827 * calling silc_packet_get_context function as well. Note that this is
828 * separate packet stream specific context, and not the same as
829 * `callback_context' in silc_packet_engine_start. Both will be delivered
830 * to the callbacks, and this context as the `stream_context' argument.
833 void silc_packet_set_context(SilcPacketStream stream, void *stream_context);
835 /****f* silccore/SilcPacketAPI/silc_packet_get_context
839 * void *silc_packet_get_context(SilcPacketStream stream);
843 * Returns the current set application context, or NULL if none is set.
846 void *silc_packet_get_context(SilcPacketStream stream);
848 /****f* silccore/SilcPacketAPI/silc_packet_set_keys
852 * void silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
853 * SilcCipher receive_key, SilcHmac send_hmac,
854 * SilcHmac receive_hmac, SilcBool rekey);
858 * Set ciphers and HMACs to be used to encrypt sent packets, and decrypt
859 * received packets. This can be called multiple times to change the
862 * If the `rekey' is TRUE this function will send SILC_PACKET_REKEY_DONE
863 * to the `stream' and will set the new keys. If it is FALSE the keys
864 * are changed but the packet is not changed.
866 * When changing keys the old cipher and HMACs will be freed. If the keys
867 * are not set at all, packets will not be encrypted or decrypted.
870 SilcBool silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
871 SilcCipher receive_key, SilcHmac send_hmac,
872 SilcHmac receive_hmac, SilcBool rekey);
874 /****f* silccore/SilcPacketAPI/silc_packet_get_keys
878 * SilcBool silc_packet_get_keys(SilcPacketStream stream,
879 * SilcCipher *send_key,
880 * SilcCipher *receive_key,
881 * SilcHmac *send_hmac,
882 * SilcHmac *receive_hmac);
886 * Returns the pointers of current ciphers and HMACs from the `stream'.
887 * Returns FALSE if keys are not set.
890 SilcBool silc_packet_get_keys(SilcPacketStream stream,
891 SilcCipher *send_key, SilcCipher *receive_key,
892 SilcHmac *send_hmac, SilcHmac *receive_hmac);
894 /****f* silccore/SilcPacketAPI/silc_packet_set_ids
898 * SilcBool silc_packet_set_ids(SilcPacketStream stream,
899 * SilcIdType src_id_type, const void *src_id
900 * SilcIdType dst_id_type, const void *dst_id);
904 * Set the source ID and destination ID to be used when sending packets to
905 * this packet stream. The IDs to be used for a packet stream can be
906 * overridden when sending packets. However, if the IDs do not ever change
907 * for the packet stream it is recommended they are set using this function.
908 * In this case they can be omitted when sending packets to the stream.
909 * It is also possible to set only source or destination ID.
912 SilcBool silc_packet_set_ids(SilcPacketStream stream,
913 SilcIdType src_id_type, const void *src_id,
914 SilcIdType dst_id_type, const void *dst_id);
916 /****f* silccore/SilcPacketAPI/silc_packet_set_ids
920 * SilcBool silc_packet_get_ids(SilcPacketStream stream,
921 * SilcBool *src_id_set, SilcID *src_id,
922 * SilcBool *dst_id_set, SilcID *dst_id);
926 * Returns source and destination IDs from the packet stream. The
927 * `src_id_set' is set to TRUE if the source ID was returned. The
928 * `dst_id_set' is set to TRUE if the destination ID was returned.
931 SilcBool silc_packet_get_ids(SilcPacketStream stream,
932 SilcBool *src_id_set, SilcID *src_id,
933 SilcBool *dst_id_set, SilcID *dst_id);
935 /****f* silccore/SilcPacketAPI/silc_packet_set_sid
939 * SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
943 * Sets new Security ID to the packet stream indicated by `stream'. This
944 * is called only if the IV Included property was set to the stream
945 * by calling silc_packet_stream_set_iv_included. This function sets
946 * new Security ID to the stream which is then included in the ciphertext
947 * of a packet. The `sid' must be 0 when it is set for the very first
948 * time and must be increased by one after each rekey. This function must
949 * be called every time new keys are added to the stream after a rekey.
951 * If this function is called when the IV Included property has not been
952 * set to the stream the `sid' will be ignored. Returns FALSE if the
953 * IV Included has not been set, TRUE otherwise.
956 SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
958 /****f* silccore/SilcPacketAPI/silc_packet_send
962 * SilcBool silc_packet_send(SilcPacketStream stream,
963 * SilcPacketType type, SilcPacketFlags flags,
964 * const unsigned char *data,
965 * SilcUInt32 data_len);
969 * Send `data' of length of `data_len' to the packet stream indicated by
970 * `stream'. If ciphers and HMACs were set using silc_packet_set_keys
971 * the packet will be encrypted and MAC will be computed for it. If
972 * silc_packet_set_ids was used to set source and destination ID for the
973 * packet stream those IDs are used in the packet. If IDs have not been
974 * set and they need to be provided then silc_packet_send_ext function
975 * should be used. Otherwise, the packet will not have IDs set at all.
976 * Returns FALSE if packet could not be sent.
979 SilcBool silc_packet_send(SilcPacketStream stream,
980 SilcPacketType type, SilcPacketFlags flags,
981 const unsigned char *data, SilcUInt32 data_len);
983 /****f* silccore/SilcPacketAPI/silc_packet_send_ext
988 * silc_packet_send_ext(SilcPacketStream stream,
989 * SilcPacketType type, SilcPacketFlags flags,
990 * SilcIdType src_id_type, void *srd_id,
991 * SilcIdType dst_id_type, void *dst_id,
992 * const unsigned char *data, SilcUInt32 data_len,
993 * SilcCipher cipher, SilcHmac hmac);
997 * Same as silc_packet_send but with this function different sending
998 * parameters can be sent as argument. This function can be used to
999 * set specific IDs, cipher and HMAC to be used in packet sending,
1000 * instead of the ones saved in the `stream'. If any of the extra
1001 * pointers are NULL, default values set to the stream will apply.
1004 SilcBool silc_packet_send_ext(SilcPacketStream stream,
1005 SilcPacketType type, SilcPacketFlags flags,
1006 SilcIdType src_id_type, void *src_id,
1007 SilcIdType dst_id_type, void *dst_id,
1008 const unsigned char *data, SilcUInt32 data_len,
1009 SilcCipher cipher, SilcHmac hmac);
1011 /****f* silccore/SilcPacketAPI/silc_packet_send_va
1015 * SilcBool silc_packet_send_va(SilcPacketStream stream,
1016 * SilcPacketType type,
1017 * SilcPacketFlags flags, ...);
1021 * Same as silc_packet_send but takes the data in as variable argument
1022 * formatted buffer (see silcbuffmt.h). The arguments must be ended
1023 * with SILC_STR_END. Returns FALSE if packet could not be sent or
1024 * the buffer could not be formatted.
1028 * // Send NEW_CLIENT packet
1029 * silc_packet_send_va(stream, SILC_PACKET_NEW_CLIENT, 0,
1030 * SILC_STR_UI_SHORT(username_len),
1031 * SILC_STR_DATA(username, username_len),
1032 * SILC_STR_UI_SHORT(realname_len),
1033 * SILC_STR_DATA(realname, realname_len),
1037 SilcBool silc_packet_send_va(SilcPacketStream stream,
1038 SilcPacketType type, SilcPacketFlags flags, ...);
1040 /****f* silccore/SilcPacketAPI/silc_packet_send_va_ext
1045 * silc_packet_send_va_ext(SilcPacketStream stream,
1046 * SilcPacketType type, SilcPacketFlags flags,
1047 * SilcIdType src_id_type, void *srd_id,
1048 * SilcIdType dst_id_type, void *dst_id,
1049 * SilcCipher cipher, SilcHmac hmac, ...);
1053 * Same as silc_packet_send_va but with this function different sending
1054 * parameters can be sent as argument. This function can be used to
1055 * set specific IDs, cipher and HMAC to be used in packet sending,
1056 * instead of the ones saved in the `stream'. If any of the extra
1057 * pointers are NULL, default values set to the stream will apply.
1060 SilcBool silc_packet_send_va_ext(SilcPacketStream stream,
1061 SilcPacketType type, SilcPacketFlags flags,
1062 SilcIdType src_id_type, void *src_id,
1063 SilcIdType dst_id_type, void *dst_id,
1064 SilcCipher cipher, SilcHmac hmac, ...);
1066 /****f* silccore/SilcPacketAPI/silc_packet_wait
1070 * void *silc_packet_wait_init(SilcPacketStream stream, ...);
1074 * Initializes a packet waiter for the packet stream `stream' and
1075 * for the variable argument list of packet types. The function
1076 * silc_packet_wait can be used to block the thread until a packet
1077 * has been received. This function is used to initialize the waiting
1078 * and to give the list of packet types that caller wish to receive.
1079 * The variable argument list must end with -1. To receive all
1080 * packets use SILC_PACKET_ANY. Returns a context that must be given
1081 * to the silc_packet_wait function as argument. Returns NULL on
1082 * error. To uninitialize the waiting call silc_packet_wait_uninit.
1086 * Note that packets may be available immediately after calling this
1087 * function and they will be buffered, until silc_packet_wait is called.
1093 * // Will wait for private message packets
1094 * waiter = silc_packet_wait_init(stream,
1095 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1099 void *silc_packet_wait_init(SilcPacketStream stream, ...);
1101 /****f* silccore/SilcPacketAPI/silc_packet_wait_uninit
1105 * void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1109 * Uninitializes the waiting context. This may be called also from
1110 * another thread while other thread is waiting for packets. This will
1111 * inform the waiting thread to stop waiting.
1114 void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
1116 /****f* silccore/SilcPacketAPI/silc_packet_wait
1120 * int silc_packet_wait(void *waiter, int timeout,
1121 * SilcPacket *return_packet)
1125 * A special function that can be used to wait for a packet to arrive.
1126 * This function will block the calling process or thread until either
1127 * a packet is received into the `return_packet' pointer or the specified
1128 * timeout value `timeout', which is in milliseconds, will expire. If
1129 * the timeout is 0, no timeout exist. Before calling this function the
1130 * silc_packet_wait_init must be called. The caller is responsible for
1131 * freeing the returned packet with silc_packet_free.
1133 * This function can be used for example from a thread that wants to
1134 * block until SILC packet has been received.
1136 * Returns 1 when packet was received, 0 if timeout occurred and -1 if
1141 * static int foo_read_data(FooContext c)
1143 * SilcPacket packet;
1147 * // Will wait for private message packets
1148 * if (c->initialized == FALSE) {
1149 * waiter = silc_packet_wait_init(stream,
1150 * SILC_PACKET_PRIVATE_MESSAGE, -1);
1151 * c->initialized = TRUE;
1155 * // Wait here until private message packet is received
1156 * if ((silc_packet_wait(waiter, 0, &packet)) < 0)
1159 * ... process packet ...
1165 int silc_packet_wait(void *waiter, int timeout, SilcPacket *return_packet);
1167 /****f* silccore/SilcPacketAPI/silc_packet_free
1171 * void silc_packet_free(SilcPacket packet);
1175 * This function is used to free the SilcPacket pointer that application
1176 * receives in the SilcPacketReceive callback. Application must free
1177 * the packet if it takes it in to processing.
1180 void silc_packet_free(SilcPacket packet);
1182 #endif /* SILCPACKET_H */