5 Author: Pekka Riikonen <priikone@silcnet.org>
7 Copyright (C) 1997 - 2001 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; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
21 /****h* silccore/SILC Channel Interface
25 * Implementations of the Channel Payload, Channel Message Payload and
26 * Channel Key Payload. The Channel Payload represents new channel and
27 * is used to distribute the information of the new channel. The Channel
28 * Message Payload is used to deliver messages to the channel. The routines
29 * for Channel Message Payload also handles the encryption and decryption
30 * of the payload. Last, the Channel Key Payload is used to distribute
31 * a new key to the channel. It is done for example every time someone
32 * joins a channel or the old key expires.
39 #include "silcdlist.h"
41 /****s* silccore/SilcChannelAPI/SilcChannelPayload
45 * typedef struct SilcChannelPayloadStruct *SilcChannelPayload;
49 * This context is the actual Channel Payload and is allocated
50 * by silc_channel_payload_parse and given as argument usually to
51 * all silc_channel_payload_* functions. It is freed by the
52 * silc_channel_payload_free function.
55 typedef struct SilcChannelPayloadStruct *SilcChannelPayload;
57 /****s* silccore/SilcChannelAPI/SilcChannelMessagePayload
62 * SilcChannelMessagePayloadStruct *SilcChannelMessagePayload;
66 * This context is the actual Channel Message Payload and is allocated
67 * by silc_channel_message_payload_parse and given as argument usually to
68 * all silc_channel_message_payload_* functions. It is freed by the
69 * silc_channel_message_payload_free function.
72 typedef struct SilcChannelMessagePayloadStruct *SilcChannelMessagePayload;
74 /****s* silccore/SilcChannelAPI/SilcChannelKeyPayload
78 * typedef struct SilcChannelKeyPayloadStruct *SilcChannelKeyPayload;
82 * This context is the actual Channel Key Payload and is allocated
83 * by silc_channel_key_payload_parse and given as argument usually to
84 * all silc_channel_key_payload_* functions. It is freed by the
85 * silc_channel_key_payload_free function.
88 typedef struct SilcChannelKeyPayloadStruct *SilcChannelKeyPayload;
90 /****d* silccore/SilcChannelAPI/SilcMessageFlags
94 * typedef SilcUInt16 SilcMessageFlags;
98 * The message flags type definition and the message flags. The
99 * message flags are used to indicate some status of the message.
100 * These flags are also used by the private message interfaces.
104 typedef SilcUInt16 SilcMessageFlags;
106 /* The message flags (shared by both channel and private messages) */
107 #define SILC_MESSAGE_FLAG_NONE 0x0000
108 #define SILC_MESSAGE_FLAG_AUTOREPLY 0x0001
109 #define SILC_MESSAGE_FLAG_NOREPLY 0x0002
110 #define SILC_MESSAGE_FLAG_ACTION 0x0004
111 #define SILC_MESSAGE_FLAG_NOTICE 0x0008
112 #define SILC_MESSAGE_FLAG_REQUEST 0x0010
113 #define SILC_MESSAGE_FLAG_SIGNED 0x0020
114 #define SILC_MESSAGE_FLAG_RESERVED 0x0040 /* to 0x0200 */
115 #define SILC_MESSAGE_FLAG_PRIVATE 0x0400 /* to 0x8000 */
120 /****f* silccore/SilcChannelAPI/silc_channel_payload_parse
125 * silc_channel_payload_parse(const unsigned char *payload,
126 * SilcUInt32 payload_len);
130 * Parses channel payload returning new channel payload structure. The
131 * `buffer' is the raw payload buffer.
134 SilcChannelPayload silc_channel_payload_parse(const unsigned char *payload,
135 SilcUInt32 payload_len);
137 /****f* silccore/SilcChannelAPI/silc_channel_payload_parse_list
142 * silc_channel_payload_parse_list(const unsigned char *payload,
143 * SilcUInt32 payload_len);
147 * Parses list of channel payloads returning list of payloads. This
148 * is equivalent to the silc_channel_payload_parse except that the `buffer'
149 * now includes multiple Channel Payloads one after the other.
152 SilcDList silc_channel_payload_parse_list(const unsigned char *payload,
153 SilcUInt32 payload_len);
155 /****f* silccore/SilcChannelAPI/silc_channel_payload_encode
159 * SilcBuffer silc_channel_payload_encode(const unsigned char *channel_name,
160 * SilcUInt16 channel_name_len,
161 * const unsigned char *channel_id,
162 * SilcUInt32 channel_id_len,
167 * Encode new channel payload and returns it as buffer.
170 SilcBuffer silc_channel_payload_encode(const unsigned char *channel_name,
171 SilcUInt16 channel_name_len,
172 const unsigned char *channel_id,
173 SilcUInt32 channel_id_len,
176 /****f* silccore/SilcChannelAPI/silc_channel_payload_free
180 * void silc_channel_payload_free(SilcChannelPayload payload);
184 * Frees Channel Payload and all data in it.
187 void silc_channel_payload_free(SilcChannelPayload payload);
189 /****f* silccore/SilcChannelAPI/silc_channel_payload_list_free
193 * void silc_channel_payload_list_free(SilcDList list);
197 * Frees list of Channel Payloads and all data in them.
200 void silc_channel_payload_list_free(SilcDList list);
202 /****f* silccore/SilcChannelAPI/silc_channel_get_name
206 * unsigned char *silc_channel_get_name(SilcChannelPayload payload,
207 * SilcUInt32 *channel_name_len);
211 * Return the channel name from the payload. The caller must not free it.
214 unsigned char *silc_channel_get_name(SilcChannelPayload payload,
215 SilcUInt32 *channel_name_len);
217 /****f* silccore/SilcChannelAPI/silc_channel_get_id
221 * unsigned char *silc_channel_get_id(SilcChannelPayload payload,
222 * SilcUInt32 *channel_id_len);
226 * Return the Channel ID data from the payload. The caller must not free it.
229 unsigned char *silc_channel_get_id(SilcChannelPayload payload,
230 SilcUInt32 *channel_id_len);
232 /****f* silccore/SilcChannelAPI/silc_channel_get_id_parse
236 * SilcChannelID *silc_channel_get_id_parse(SilcChannelPayload payload);
240 * Return the Channel ID as parsed ID. This is equivalent to the
241 * silc_channel_get_id execpt that the ID is already parsed. The caller
242 * must free the parsed Channel ID.
245 SilcChannelID *silc_channel_get_id_parse(SilcChannelPayload payload);
247 /****f* silccore/SilcChannelAPI/silc_channel_get_mode
251 * SilcUInt32 silc_channel_get_mode(SilcChannelPayload payload);
255 * Return the mode. The mode is arbitrary. It can be the mode of the
256 * channel or perhaps the mode of the client on the channel. The protocol
257 * dictates what the usage of the mode is in different circumstances.
260 SilcUInt32 silc_channel_get_mode(SilcChannelPayload payload);
262 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_decrypt
266 * bool silc_channel_message_payload_decrypt(unsigned char *data,
273 * Decrypt the channel message. First push the IV out of the packet `data'.
274 * The IV is used in the decryption process. Then decrypt the message.
275 * After decryption, take the MAC from the decrypted packet, compute MAC
276 * and compare the MACs. If they match, the decryption was successful
277 * and we have the channel message ready to be displayed.
279 * This is usually used by the Channel Message interface itself but can
280 * be called by the appliation if separate decryption process is required.
281 * For example server might need to call this directly in some
282 * circumstances. The `cipher' is used to decrypt the payload.
284 * If the `hmac' is no provided then the MAC of the channel message is
288 bool silc_channel_message_payload_decrypt(unsigned char *data,
293 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_parse
297 * SilcChannelMessagePayload
298 * silc_channel_message_payload_parse(const unsigned char *payload,
299 * SilcUInt32 payload_len,
305 * Parses channel message payload returning new channel payload structure.
306 * This also decrypts it and checks the MAC. The `cipher's is used to
307 * decrypt the payload.
309 * If the `hmac' is no provided then the MAC of the channel message is
313 SilcChannelMessagePayload
314 silc_channel_message_payload_parse(unsigned char *payload,
315 SilcUInt32 payload_len,
319 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_encode
323 * SilcBuffer silc_channel_message_payload_encode(SilcUInt16 flags,
324 * SilcUInt16 data_len,
325 * const unsigned char *data,
334 * Encodes channel message payload into a buffer and returns it. This
335 * is used to add channel message payload into a packet. As the channel
336 * payload is encrypted separately from other parts of the packet padding
337 * must be applied to the payload. The function generates the padding
338 * automatically from random data. The `cipher' is the cipher used
339 * encrypt the payload and `hmac' is used to compute the MAC for the
340 * payload. If `rng' is NULL then global RNG is used, if non-NULL then
344 SilcBuffer silc_channel_message_payload_encode(SilcUInt16 flags,
346 const unsigned char *data,
353 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_free
358 * silc_channel_message_payload_free(SilcChannelMessagePayload payload);
362 * Free's Channel Message Payload and all data in it.
365 void silc_channel_message_payload_free(SilcChannelMessagePayload payload);
367 /****f* silccore/SilcChannelAPI/silc_channel_message_get_flags
372 * silc_channel_message_get_flags(SilcChannelMessagePayload payload);
376 * Returns the message flags from the payload.
380 silc_channel_message_get_flags(SilcChannelMessagePayload payload);
382 /****f* silccore/SilcChannelAPI/silc_channel_message_get_data
387 * silc_channel_message_get_data(SilcChannelMessagePayload payload,
388 * SilcUInt32 *data_len);
392 * Return the data in the payload, that is, the actual channel message.
393 * The caller must not free it.
396 unsigned char *silc_channel_message_get_data(SilcChannelMessagePayload payload,
397 SilcUInt32 *data_len);
399 /****f* silccore/SilcChannelAPI/silc_channel_message_get_mac
404 * silc_channel_message_get_mac(SilcChannelMessagePayload payload);
408 * Return the MAC of the payload. The caller must already know the
409 * length of the MAC. The caller must not free the MAC.
412 unsigned char *silc_channel_message_get_mac(SilcChannelMessagePayload payload);
414 /****f* silccore/SilcChannelAPI/silc_channel_message_get_iv
419 * silc_channel_message_get_iv(SilcChannelMessagePayload payload);
423 * Return the IV of the payload. The caller must already know the
424 * length of the IV. The caller must not free the IV.
427 unsigned char *silc_channel_message_get_iv(SilcChannelMessagePayload payload);
429 /****f* silccore/SilcChannelAPI/silc_channel_key_payload_parse
433 * SilcChannelKeyPayload
434 * silc_channel_key_payload_parse(const unsigned char *payload,
435 * uin32 payload_len);
439 * Parses channel key payload returning new channel key payload
443 SilcChannelKeyPayload
444 silc_channel_key_payload_parse(const unsigned char *payload,
445 SilcUInt32 payload_len);
447 /****f* silccore/SilcChannelAPI/silc_channel_key_payload_encode
451 * SilcBuffer silc_channel_key_payload_encode(SilcUInt16 id_len,
452 * const unsigned char *id,
453 * SilcUInt16 cipher_len,
454 * const unsigned char *cipher,
455 * SilcUInt16 key_len,
456 * const unsigned char *key);
460 * Encodes channel key payload into a buffer and returns it. This is used
461 * to add channel key payload into a packet.
464 SilcBuffer silc_channel_key_payload_encode(SilcUInt16 id_len,
465 const unsigned char *id,
466 SilcUInt16 cipher_len,
467 const unsigned char *cipher,
469 const unsigned char *key);
471 /****f* silccore/SilcChannelAPI/silc_channel_key_payload_free
475 * void silc_channel_key_payload_free(SilcChannelKeyPayload payload);
479 * Frees the Channel Key Payload and all data in it.
482 void silc_channel_key_payload_free(SilcChannelKeyPayload payload);
484 /****f* silccore/SilcChannelAPI/silc_channel_key_get_id
488 * unsigned char *silc_channel_key_get_id(SilcChannelKeyPayload payload,
489 * SilcUInt32 *id_len);
493 * Return the Channel ID data from the payload. The caller must not
497 unsigned char *silc_channel_key_get_id(SilcChannelKeyPayload payload,
500 /****f* silccore/SilcChannelAPI/silc_channel_key_get_cipher
504 * unsigned char *silc_channel_key_get_cipher(SilcChannelKeyPayload payload,
505 * SilcUInt32 *cipher_len);
509 * Return the name of the cipher from the payload. The caller must not
513 unsigned char *silc_channel_key_get_cipher(SilcChannelKeyPayload payload,
514 SilcUInt32 *cipher_len);
516 /****f* silccore/SilcChannelAPI/silc_channel_key_get_key
520 * unsigned char *silc_channel_key_get_key(SilcChannelKeyPayload payload,
521 * SilcUInt32 *key_len);
525 * Return the raw key material from the payload. The caller must not
529 unsigned char *silc_channel_key_get_key(SilcChannelKeyPayload payload,
530 SilcUInt32 *key_len);