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_REPLY 0x0040
115 #define SILC_MESSAGE_FLAG_DATA 0x0080
116 #define SILC_MESSAGE_FLAG_RESERVED 0x0100 /* to 0x0800 */
117 #define SILC_MESSAGE_FLAG_PRIVATE 0x1000 /* to 0x8000 */
122 /****f* silccore/SilcChannelAPI/silc_channel_payload_parse
127 * silc_channel_payload_parse(const unsigned char *payload,
128 * SilcUInt32 payload_len);
132 * Parses channel payload returning new channel payload structure. The
133 * `buffer' is the raw payload buffer.
136 SilcChannelPayload silc_channel_payload_parse(const unsigned char *payload,
137 SilcUInt32 payload_len);
139 /****f* silccore/SilcChannelAPI/silc_channel_payload_parse_list
144 * silc_channel_payload_parse_list(const unsigned char *payload,
145 * SilcUInt32 payload_len);
149 * Parses list of channel payloads returning list of payloads. This
150 * is equivalent to the silc_channel_payload_parse except that the `buffer'
151 * now includes multiple Channel Payloads one after the other.
154 SilcDList silc_channel_payload_parse_list(const unsigned char *payload,
155 SilcUInt32 payload_len);
157 /****f* silccore/SilcChannelAPI/silc_channel_payload_encode
161 * SilcBuffer silc_channel_payload_encode(const unsigned char *channel_name,
162 * SilcUInt16 channel_name_len,
163 * const unsigned char *channel_id,
164 * SilcUInt32 channel_id_len,
169 * Encode new channel payload and returns it as buffer.
172 SilcBuffer silc_channel_payload_encode(const unsigned char *channel_name,
173 SilcUInt16 channel_name_len,
174 const unsigned char *channel_id,
175 SilcUInt32 channel_id_len,
178 /****f* silccore/SilcChannelAPI/silc_channel_payload_free
182 * void silc_channel_payload_free(SilcChannelPayload payload);
186 * Frees Channel Payload and all data in it.
189 void silc_channel_payload_free(SilcChannelPayload payload);
191 /****f* silccore/SilcChannelAPI/silc_channel_payload_list_free
195 * void silc_channel_payload_list_free(SilcDList list);
199 * Frees list of Channel Payloads and all data in them.
202 void silc_channel_payload_list_free(SilcDList list);
204 /****f* silccore/SilcChannelAPI/silc_channel_get_name
208 * unsigned char *silc_channel_get_name(SilcChannelPayload payload,
209 * SilcUInt32 *channel_name_len);
213 * Return the channel name from the payload. The caller must not free it.
216 unsigned char *silc_channel_get_name(SilcChannelPayload payload,
217 SilcUInt32 *channel_name_len);
219 /****f* silccore/SilcChannelAPI/silc_channel_get_id
223 * unsigned char *silc_channel_get_id(SilcChannelPayload payload,
224 * SilcUInt32 *channel_id_len);
228 * Return the Channel ID data from the payload. The caller must not free it.
231 unsigned char *silc_channel_get_id(SilcChannelPayload payload,
232 SilcUInt32 *channel_id_len);
234 /****f* silccore/SilcChannelAPI/silc_channel_get_id_parse
238 * SilcChannelID *silc_channel_get_id_parse(SilcChannelPayload payload);
242 * Return the Channel ID as parsed ID. This is equivalent to the
243 * silc_channel_get_id execpt that the ID is already parsed. The caller
244 * must free the parsed Channel ID.
247 SilcChannelID *silc_channel_get_id_parse(SilcChannelPayload payload);
249 /****f* silccore/SilcChannelAPI/silc_channel_get_mode
253 * SilcUInt32 silc_channel_get_mode(SilcChannelPayload payload);
257 * Return the mode. The mode is arbitrary. It can be the mode of the
258 * channel or perhaps the mode of the client on the channel. The protocol
259 * dictates what the usage of the mode is in different circumstances.
262 SilcUInt32 silc_channel_get_mode(SilcChannelPayload payload);
264 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_decrypt
268 * bool silc_channel_message_payload_decrypt(unsigned char *data,
275 * Decrypt the channel message. First push the IV out of the packet `data'.
276 * The IV is used in the decryption process. Then decrypt the message.
277 * After decryption, take the MAC from the decrypted packet, compute MAC
278 * and compare the MACs. If they match, the decryption was successful
279 * and we have the channel message ready to be displayed.
281 * This is usually used by the Channel Message interface itself but can
282 * be called by the appliation if separate decryption process is required.
283 * For example server might need to call this directly in some
284 * circumstances. The `cipher' is used to decrypt the payload.
286 * If the `hmac' is no provided then the MAC of the channel message is
290 bool silc_channel_message_payload_decrypt(unsigned char *data,
295 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_parse
299 * SilcChannelMessagePayload
300 * silc_channel_message_payload_parse(const unsigned char *payload,
301 * SilcUInt32 payload_len,
307 * Parses channel message payload returning new channel payload structure.
308 * This also decrypts it and checks the MAC. The `cipher's is used to
309 * decrypt the payload.
311 * If the `hmac' is no provided then the MAC of the channel message is
315 SilcChannelMessagePayload
316 silc_channel_message_payload_parse(unsigned char *payload,
317 SilcUInt32 payload_len,
321 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_encrypt
325 * bool silc_channel_message_payload_encrypt(unsigned char *data,
326 * SilcUInt32 data_len,
327 * SilcUInt32 true_len,
335 * This function is used to encrypt the Channel Messsage Payload which is
336 * the `data' and `data_len'. The `data_len' is the data length which is
337 * used to create MAC out of. The `true_len' is the true length of `data'
338 * message payload and is used assemble rest of the packet after MAC
339 * creation. The `true_len' length packet will then be encrypted.
341 * This is usually used by the Channel Message interface itself but can
342 * be called by the appliation if separate encryption process is required.
343 * For example server might need to call this directly in some
344 * circumstances. The `cipher' is used to encrypt the payload.
347 bool silc_channel_message_payload_encrypt(unsigned char *data,
355 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_encode
359 * SilcBuffer silc_channel_message_payload_encode(SilcUInt16 flags,
360 * SilcUInt16 data_len,
361 * const unsigned char *data,
370 * Encodes channel message payload into a buffer and returns it. This
371 * is used to add channel message payload into a packet. As the channel
372 * payload is encrypted separately from other parts of the packet padding
373 * must be applied to the payload. The function generates the padding
374 * automatically from random data. The `cipher' is the cipher used
375 * encrypt the payload and `hmac' is used to compute the MAC for the
376 * payload. If `rng' is NULL then global RNG is used, if non-NULL then
380 SilcBuffer silc_channel_message_payload_encode(SilcUInt16 flags,
382 const unsigned char *data,
389 /****f* silccore/SilcChannelAPI/silc_channel_message_payload_free
394 * silc_channel_message_payload_free(SilcChannelMessagePayload payload);
398 * Free's Channel Message Payload and all data in it.
401 void silc_channel_message_payload_free(SilcChannelMessagePayload payload);
403 /****f* silccore/SilcChannelAPI/silc_channel_message_get_flags
408 * silc_channel_message_get_flags(SilcChannelMessagePayload payload);
412 * Returns the message flags from the payload.
416 silc_channel_message_get_flags(SilcChannelMessagePayload payload);
418 /****f* silccore/SilcChannelAPI/silc_channel_message_get_data
423 * silc_channel_message_get_data(SilcChannelMessagePayload payload,
424 * SilcUInt32 *data_len);
428 * Return the data in the payload, that is, the actual channel message.
429 * The caller must not free it.
432 unsigned char *silc_channel_message_get_data(SilcChannelMessagePayload payload,
433 SilcUInt32 *data_len);
435 /****f* silccore/SilcChannelAPI/silc_channel_message_get_mac
440 * silc_channel_message_get_mac(SilcChannelMessagePayload payload);
444 * Return the MAC of the payload. The caller must already know the
445 * length of the MAC. The caller must not free the MAC.
448 unsigned char *silc_channel_message_get_mac(SilcChannelMessagePayload payload);
450 /****f* silccore/SilcChannelAPI/silc_channel_message_get_iv
455 * silc_channel_message_get_iv(SilcChannelMessagePayload payload);
459 * Return the IV of the payload. The caller must already know the
460 * length of the IV. The caller must not free the IV.
463 unsigned char *silc_channel_message_get_iv(SilcChannelMessagePayload payload);
465 /****f* silccore/SilcChannelAPI/silc_channel_key_payload_parse
469 * SilcChannelKeyPayload
470 * silc_channel_key_payload_parse(const unsigned char *payload,
471 * uin32 payload_len);
475 * Parses channel key payload returning new channel key payload
479 SilcChannelKeyPayload
480 silc_channel_key_payload_parse(const unsigned char *payload,
481 SilcUInt32 payload_len);
483 /****f* silccore/SilcChannelAPI/silc_channel_key_payload_encode
487 * SilcBuffer silc_channel_key_payload_encode(SilcUInt16 id_len,
488 * const unsigned char *id,
489 * SilcUInt16 cipher_len,
490 * const unsigned char *cipher,
491 * SilcUInt16 key_len,
492 * const unsigned char *key);
496 * Encodes channel key payload into a buffer and returns it. This is used
497 * to add channel key payload into a packet.
500 SilcBuffer silc_channel_key_payload_encode(SilcUInt16 id_len,
501 const unsigned char *id,
502 SilcUInt16 cipher_len,
503 const unsigned char *cipher,
505 const unsigned char *key);
507 /****f* silccore/SilcChannelAPI/silc_channel_key_payload_free
511 * void silc_channel_key_payload_free(SilcChannelKeyPayload payload);
515 * Frees the Channel Key Payload and all data in it.
518 void silc_channel_key_payload_free(SilcChannelKeyPayload payload);
520 /****f* silccore/SilcChannelAPI/silc_channel_key_get_id
524 * unsigned char *silc_channel_key_get_id(SilcChannelKeyPayload payload,
525 * SilcUInt32 *id_len);
529 * Return the Channel ID data from the payload. The caller must not
533 unsigned char *silc_channel_key_get_id(SilcChannelKeyPayload payload,
536 /****f* silccore/SilcChannelAPI/silc_channel_key_get_cipher
540 * unsigned char *silc_channel_key_get_cipher(SilcChannelKeyPayload payload,
541 * SilcUInt32 *cipher_len);
545 * Return the name of the cipher from the payload. The caller must not
549 unsigned char *silc_channel_key_get_cipher(SilcChannelKeyPayload payload,
550 SilcUInt32 *cipher_len);
552 /****f* silccore/SilcChannelAPI/silc_channel_key_get_key
556 * unsigned char *silc_channel_key_get_key(SilcChannelKeyPayload payload,
557 * SilcUInt32 *key_len);
561 * Return the raw key material from the payload. The caller must not
565 unsigned char *silc_channel_key_get_key(SilcChannelKeyPayload payload,
566 SilcUInt32 *key_len);