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; 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 * Created: Fri Jul 25 18:52:14 1997
24 #include "silcincludes.h"
26 /******************************************************************************
28 Packet Sending Routines
30 ******************************************************************************/
32 /* Actually sends the packet. This flushes the connections outgoing data
33 buffer. If data is sent directly to the network this returns the bytes
34 written, if error occured this returns -1 and if the data could not
35 be written directly to the network at this time this returns -2, in
36 which case the data should be queued by the caller and sent at some
37 later time. If `force_send' is TRUE this attempts to write the data
38 directly to the network, if FALSE, this returns -2. */
40 int silc_packet_send(SilcSocketConnection sock, bool force_send)
42 SILC_LOG_DEBUG(("Sending packet to %s:%d [%s]", sock->hostname,
44 (sock->type == SILC_SOCKET_TYPE_UNKNOWN ? "Unknown" :
45 sock->type == SILC_SOCKET_TYPE_CLIENT ? "Client" :
46 sock->type == SILC_SOCKET_TYPE_SERVER ? "Server" :
49 /* Send now if forced to do so */
50 if (force_send == TRUE) {
53 SILC_LOG_DEBUG(("Forcing packet send, packet sent immediately"));
55 /* Write to network */
56 ret = silc_socket_write(sock);
59 SILC_LOG_ERROR(("Error sending packet, dropped"));
64 SILC_LOG_DEBUG(("Could not force the send, packet put to queue"));
67 SILC_LOG_DEBUG(("Packet in queue"));
72 /* Encrypts a packet. This also creates HMAC of the packet before
73 encryption and adds the HMAC at the end of the buffer. This assumes
74 that there is enough free space at the end of the buffer to add the
75 computed HMAC. This is the normal way of encrypting packets, if some
76 other process of HMAC computing and encryption is needed this function
79 void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac, uint32 sequence,
80 SilcBuffer buffer, uint32 len)
82 unsigned char mac[32];
85 /* Compute HMAC. This assumes that HMAC is created from the entire
86 data area thus this uses the length found in buffer, not the length
92 SILC_PUT32_MSB(sequence, psn);
93 silc_hmac_update(hmac, psn, 4);
94 silc_hmac_update(hmac, buffer->data, buffer->len);
95 silc_hmac_final(hmac, mac, &mac_len);
96 silc_buffer_put_tail(buffer, mac, mac_len);
97 memset(mac, 0, sizeof(mac));
100 /* Encrypt the data area of the packet. */
102 SILC_LOG_DEBUG(("Encrypting packet, cipher %s, len %d",
103 cipher->cipher->name, len));
104 silc_cipher_encrypt(cipher, buffer->data, buffer->data, len, cipher->iv);
107 /* Pull the HMAC into the visible data area in the buffer */
109 silc_buffer_pull_tail(buffer, mac_len);
112 /* Assembles a new packet to be ready for send out. The buffer sent as
113 argument must include the data to be sent and it must not be encrypted.
114 The packet also must have enough free space so that the SILC header
115 and padding maybe added to the packet. The packet is encrypted after
116 this function has returned.
118 The buffer sent as argument should be something like following:
120 --------------------------------------------
121 | head | data | tail |
122 --------------------------------------------
126 So that the SILC header and 1 - 16 bytes of padding can fit to
127 the buffer. After assembly the buffer might look like this:
129 --------------------------------------------
131 --------------------------------------------
133 Start of assembled packet
135 Packet construct is as follows:
138 2 bytes Payload length
141 1 byte Padding length
143 1 bytes Source ID Length
144 1 bytes Destination ID Length
145 1 byte Source ID Type
147 1 byte Destination ID Type
148 n bytes Destination ID
154 All fields in the packet will be authenticated by MAC. The MAC is
155 not computed here, it must be computed separately before encrypting
160 void silc_packet_assemble(SilcPacketContext *ctx, SilcCipher cipher)
162 unsigned char tmppad[SILC_PACKET_MAX_PADLEN];
163 int block_len = cipher ? silc_cipher_get_block_len(cipher) : 0;
166 SILC_LOG_DEBUG(("Assembling outgoing packet"));
168 /* Get the true length of the packet. This is saved as payload length
169 into the packet header. This does not include the length of the
172 ctx->truelen = ctx->buffer->len + SILC_PACKET_HEADER_LEN +
173 ctx->src_id_len + ctx->dst_id_len;
175 /* Calculate the length of the padding. The padding is calculated from
176 the data that will be encrypted. */
179 ctx->padlen = SILC_PACKET_PADLEN_MAX(ctx->truelen);
181 ctx->padlen = SILC_PACKET_PADLEN(ctx->truelen, block_len);
184 /* Put the start of the data section to the right place. */
185 silc_buffer_push(ctx->buffer, SILC_PACKET_HEADER_LEN +
186 ctx->src_id_len + ctx->dst_id_len + ctx->padlen);
188 /* Get random padding */
190 for (i = 0; i < ctx->padlen; i++) tmppad[i] =
191 silc_rng_global_get_byte_fast();
193 /* XXX: For testing - to be removed */
194 memset(tmppad, 65, sizeof(tmppad));
197 /* Create the packet. This creates the SILC header and adds padding,
198 rest of the buffer remains as it is. */
199 silc_buffer_format(ctx->buffer,
200 SILC_STR_UI_SHORT(ctx->truelen),
201 SILC_STR_UI_CHAR(ctx->flags),
202 SILC_STR_UI_CHAR(ctx->type),
203 SILC_STR_UI_CHAR(ctx->padlen),
205 SILC_STR_UI_CHAR(ctx->src_id_len),
206 SILC_STR_UI_CHAR(ctx->dst_id_len),
207 SILC_STR_UI_CHAR(ctx->src_id_type),
208 SILC_STR_UI_XNSTRING(ctx->src_id, ctx->src_id_len),
209 SILC_STR_UI_CHAR(ctx->dst_id_type),
210 SILC_STR_UI_XNSTRING(ctx->dst_id, ctx->dst_id_len),
211 SILC_STR_UI_XNSTRING(tmppad, ctx->padlen),
214 SILC_LOG_HEXDUMP(("Assembled packet, len %d", ctx->buffer->len),
215 ctx->buffer->data, ctx->buffer->len);
217 SILC_LOG_DEBUG(("Outgoing packet assembled"));
220 /* Prepare outgoing data buffer for packet sending. This moves the data
221 area so that new packet may be added into it. If needed this allocates
222 more space to the buffer. This handles directly the connection's
223 outgoing buffer in SilcSocketConnection object. */
225 void silc_packet_send_prepare(SilcSocketConnection sock,
232 totlen = header_len + padlen + data_len;
234 /* Prepare the outgoing buffer for packet sending. */
236 /* Allocate new buffer. This is done only once per connection. */
237 SILC_LOG_DEBUG(("Allocating outgoing data buffer"));
239 if (totlen > SILC_PACKET_DEFAULT_SIZE)
240 sock->outbuf = silc_buffer_alloc(totlen);
242 sock->outbuf = silc_buffer_alloc(SILC_PACKET_DEFAULT_SIZE);
243 silc_buffer_pull_tail(sock->outbuf, totlen);
244 silc_buffer_pull(sock->outbuf, header_len + padlen);
246 if (SILC_IS_OUTBUF_PENDING(sock)) {
247 /* There is some pending data in the buffer. */
249 /* Allocate more space if needed */
250 if ((sock->outbuf->end - sock->outbuf->tail) <
252 SILC_LOG_DEBUG(("Reallocating outgoing data buffer"));
253 sock->outbuf = silc_buffer_realloc(sock->outbuf,
254 sock->outbuf->truelen +
258 oldlen = sock->outbuf->len;
259 silc_buffer_pull_tail(sock->outbuf, totlen);
260 silc_buffer_pull(sock->outbuf, header_len + padlen + oldlen);
262 /* Buffer is free for use */
263 silc_buffer_clear(sock->outbuf);
265 /* Allocate more space if needed */
266 if ((sock->outbuf->end - sock->outbuf->tail) < (totlen + 20)) {
267 SILC_LOG_DEBUG(("Reallocating outgoing data buffer"));
268 sock->outbuf = silc_buffer_realloc(sock->outbuf,
269 sock->outbuf->truelen +
273 silc_buffer_pull_tail(sock->outbuf, totlen);
274 silc_buffer_pull(sock->outbuf, header_len + padlen);
279 /******************************************************************************
281 Packet Reception Routines
283 ******************************************************************************/
285 static int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
286 uint32 sequence, SilcBuffer buffer,
289 /* Receives packet from network and reads the data into connection's
290 incoming data buffer. If the data was read directly this returns the
291 read bytes, if error occured this returns -1, if the data could not
292 be read directly at this time this returns -2 in which case the data
293 should be read again at some later time, or If EOF occured this returns
296 int silc_packet_receive(SilcSocketConnection sock)
300 SILC_LOG_DEBUG(("Receiving packet from %s:%d [%s]", sock->hostname,
302 (sock->type == SILC_SOCKET_TYPE_UNKNOWN ? "Unknown" :
303 sock->type == SILC_SOCKET_TYPE_CLIENT ? "Client" :
304 sock->type == SILC_SOCKET_TYPE_SERVER ? "Server" :
307 /* Read some data from connection */
308 ret = silc_socket_read(sock);
313 /* Processes and decrypts the incmoing data, and calls parser callback
314 for each received packet that will handle the actual packet parsing.
315 If more than one packet was received this calls the parser multiple
316 times. The parser callback will get context SilcPacketParserContext
317 that includes the packet and the `parser_context' sent to this
320 The `local_is_router' indicates whether the caller is router server
321 in which case the receiving process of a certain packet types may
322 be special. Normal server and client must set it to FALSE. The
323 SilcPacketParserContext will indicate also whether the received
324 packet was normal or special packet. */
326 void silc_packet_receive_process(SilcSocketConnection sock,
327 bool local_is_router,
328 SilcCipher cipher, SilcHmac hmac,
330 SilcPacketParserCallback parser,
331 void *parser_context)
333 SilcPacketParserContext *parse_ctx;
334 int packetlen, paddedlen, mac_len = 0;
337 /* Do not process for disconnected connection */
338 if (SILC_IS_DISCONNECTED(sock))
341 if (sock->inbuf->len < SILC_PACKET_MIN_HEADER_LEN)
345 mac_len = silc_hmac_len(hmac);
347 /* Parse the packets from the data */
348 while (sock->inbuf->len > 0 && cont) {
350 if (sock->inbuf->len < SILC_PACKET_MIN_HEADER_LEN) {
351 SILC_LOG_DEBUG(("Partial packet in queue, waiting for the rest"));
355 /* Decrypt first 16 bytes of the packet */
356 if (!SILC_IS_INBUF_PENDING(sock) && cipher)
357 silc_cipher_decrypt(cipher, sock->inbuf->data, sock->inbuf->data,
358 SILC_PACKET_MIN_HEADER_LEN, cipher->iv);
360 /* Get packet lenght and full packet length with padding */
361 SILC_PACKET_LENGTH(sock->inbuf, packetlen, paddedlen);
364 if (packetlen < SILC_PACKET_MIN_LEN) {
365 SILC_LOG_DEBUG(("Received invalid packet, dropped"));
366 silc_buffer_clear(sock->inbuf);
370 if (sock->inbuf->len < paddedlen + mac_len) {
371 SILC_LOG_DEBUG(("Received partial packet, waiting for the rest"
372 "(%d < %d)", sock->inbuf->len, paddedlen + mac_len));
373 SILC_SET_INBUF_PENDING(sock);
377 SILC_UNSET_INBUF_PENDING(sock);
378 parse_ctx = silc_calloc(1, sizeof(*parse_ctx));
379 parse_ctx->packet = silc_packet_context_alloc();
380 parse_ctx->packet->buffer = silc_buffer_alloc(paddedlen + mac_len);
381 parse_ctx->packet->padlen = sock->inbuf->data[4];
382 parse_ctx->packet->sequence = sequence++;
383 parse_ctx->sock = sock;
384 parse_ctx->context = parser_context;
386 silc_buffer_pull_tail(parse_ctx->packet->buffer,
387 SILC_BUFFER_END(parse_ctx->packet->buffer));
388 silc_buffer_put(parse_ctx->packet->buffer, sock->inbuf->data,
389 paddedlen + mac_len);
391 SILC_LOG_HEXDUMP(("Incoming packet (%d) (%dB decrypted), len %d",
392 sequence - 1, SILC_PACKET_MIN_HEADER_LEN,
393 paddedlen + mac_len),
394 sock->inbuf->data, paddedlen + mac_len);
396 /* Check whether this is normal or special packet */
397 if (local_is_router) {
398 if (sock->inbuf->data[3] == SILC_PACKET_PRIVATE_MESSAGE &&
399 (sock->inbuf->data[2] & SILC_PACKET_FLAG_PRIVMSG_KEY))
400 parse_ctx->normal = FALSE;
401 else if (sock->inbuf->data[3] != SILC_PACKET_CHANNEL_MESSAGE ||
402 (sock->inbuf->data[3] == SILC_PACKET_CHANNEL_MESSAGE &&
403 sock->type == SILC_SOCKET_TYPE_ROUTER))
404 parse_ctx->normal = TRUE;
406 if (sock->inbuf->data[3] == SILC_PACKET_PRIVATE_MESSAGE &&
407 (sock->inbuf->data[2] & SILC_PACKET_FLAG_PRIVMSG_KEY))
408 parse_ctx->normal = FALSE;
409 else if (sock->inbuf->data[3] != SILC_PACKET_CHANNEL_MESSAGE)
410 parse_ctx->normal = TRUE;
413 /* Decrypt rest of the packet */
415 if (silc_packet_decrypt(cipher, hmac, parse_ctx->packet->sequence,
416 parse_ctx->packet->buffer,
417 parse_ctx->normal) == -1) {
418 SILC_LOG_WARNING(("Packet decryption failed %s:%d [%s]",
419 sock->hostname, sock->port,
420 (sock->type == SILC_SOCKET_TYPE_UNKNOWN ? "Unknown" :
421 sock->type == SILC_SOCKET_TYPE_CLIENT ? "Client" :
422 sock->type == SILC_SOCKET_TYPE_SERVER ? "Server" :
426 /* Pull the packet from inbuf thus we'll get the next one
428 silc_buffer_pull(sock->inbuf, paddedlen + mac_len);
430 /* Call the parser */
431 cont = (*parser)(parse_ctx, parser_context);
434 if (cont == FALSE && sock->inbuf->len > 0)
437 SILC_LOG_DEBUG(("Clearing inbound buffer"));
438 silc_buffer_clear(sock->inbuf);
441 /* Checks MAC in the packet. Returns TRUE if MAC is Ok. This is called
442 after packet has been totally decrypted and parsed. */
444 static int silc_packet_check_mac(SilcHmac hmac, SilcBuffer buffer,
449 unsigned char mac[32], psn[4];
452 SILC_LOG_DEBUG(("Verifying MAC"));
454 /* Compute HMAC of packet */
456 memset(mac, 0, sizeof(mac));
457 silc_hmac_init(hmac);
458 SILC_PUT32_MSB(sequence, psn);
459 silc_hmac_update(hmac, psn, 4);
460 silc_hmac_update(hmac, buffer->data, buffer->len);
461 silc_hmac_final(hmac, mac, &mac_len);
463 /* Compare the HMAC's (buffer->tail has the packet's HMAC) */
464 if (memcmp(mac, buffer->tail, mac_len)) {
465 SILC_LOG_ERROR(("MAC failed"));
469 SILC_LOG_DEBUG(("MAC is Ok"));
470 memset(mac, 0, sizeof(mac));
476 /* Decrypts rest of the packet (after decrypting just the SILC header).
477 After calling this function the packet is ready to be parsed by calling
478 silc_packet_parse. If everything goes without errors this returns TRUE,
479 if packet is malformed this returns FALSE. */
481 static int silc_packet_decrypt_rest(SilcCipher cipher, SilcHmac hmac,
486 /* Pull MAC from packet before decryption */
488 if ((buffer->len - silc_hmac_len(hmac)) > SILC_PACKET_MIN_LEN) {
489 silc_buffer_push_tail(buffer, silc_hmac_len(hmac));
491 SILC_LOG_DEBUG(("Bad MAC length in packet, packet dropped"));
496 SILC_LOG_DEBUG(("Decrypting rest of the packet"));
498 /* Decrypt rest of the packet */
499 silc_buffer_pull(buffer, SILC_PACKET_MIN_HEADER_LEN);
500 silc_cipher_decrypt(cipher, buffer->data, buffer->data, buffer->len,
502 silc_buffer_push(buffer, SILC_PACKET_MIN_HEADER_LEN);
504 SILC_LOG_HEXDUMP(("Fully decrypted packet, len %d", buffer->len),
505 buffer->data, buffer->len);
511 /* Decrypts rest of the SILC Packet header that has been decrypted partly
512 already. This decrypts the padding of the packet also. After calling
513 this function the packet is ready to be parsed by calling function
514 silc_packet_parse. This is used in special packet reception (protocol
515 defines the way of decrypting special packets). */
517 static int silc_packet_decrypt_rest_special(SilcCipher cipher,
521 /* Decrypt rest of the header plus padding */
525 /* Pull MAC from packet before decryption */
527 if ((buffer->len - silc_hmac_len(hmac)) > SILC_PACKET_MIN_LEN) {
528 silc_buffer_push_tail(buffer, silc_hmac_len(hmac));
530 SILC_LOG_DEBUG(("Bad MAC length in packet, packet dropped"));
535 SILC_LOG_DEBUG(("Decrypting rest of the header"));
537 /* padding length + src id len + dst id len + header length - 16
538 bytes already decrypted, gives the rest of the encrypted packet */
539 len = (((uint8)buffer->data[4] + (uint8)buffer->data[6] +
540 (uint8)buffer->data[7] + SILC_PACKET_HEADER_LEN) -
541 SILC_PACKET_MIN_HEADER_LEN);
543 silc_buffer_pull(buffer, SILC_PACKET_MIN_HEADER_LEN);
544 if (len > buffer->len) {
545 SILC_LOG_DEBUG(("Garbage in header of packet, bad packet length, "
549 silc_cipher_decrypt(cipher, buffer->data, buffer->data, len, cipher->iv);
550 silc_buffer_push(buffer, SILC_PACKET_MIN_HEADER_LEN);
551 SILC_LOG_HEXDUMP(("packet, len %d", buffer->len),
552 buffer->data, buffer->len);
558 /* Decrypts a packet. This assumes that typical SILC packet is the
559 packet to be decrypted and thus checks for normal and special SILC
560 packets and can handle both of them. This also computes and checks
561 the HMAC of the packet. If any other special or customized decryption
562 processing is required this function cannot be used. This returns
563 -1 on error, 0 when packet is normal packet and 1 when the packet
564 is special and requires special processing.
566 The `check_packet' is a callback funtion that this function will
567 call. The callback relates to the checking whether the packet is
568 normal packet or special packet and how it should be processed. If
569 the callback return TRUE the packet is normal and FALSE if the packet
570 is special and requires special procesing. */
572 static int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
573 uint32 sequence, SilcBuffer buffer,
576 /* If the packet type is not any special type lets decrypt rest
577 of the packet here. */
578 if (normal == TRUE) {
579 /* Normal packet, decrypt rest of the packet */
580 if (!silc_packet_decrypt_rest(cipher, hmac, buffer))
584 if (!silc_packet_check_mac(hmac, buffer, sequence))
589 /* Packet requires special handling, decrypt rest of the header.
590 This only decrypts. */
591 if (!silc_packet_decrypt_rest_special(cipher, hmac, buffer))
595 if (!silc_packet_check_mac(hmac, buffer, sequence))
602 /* Parses the packet. This is called when a whole packet is ready to be
603 parsed. The buffer sent must be already decrypted before calling this
604 function. The len argument must be the true length of the packet. This
605 function returns the type of the packet. The data section of the
606 buffer is parsed, not head or tail sections. */
608 SilcPacketType silc_packet_parse(SilcPacketContext *ctx, SilcCipher cipher)
610 SilcBuffer buffer = ctx->buffer;
614 SILC_LOG_DEBUG(("Parsing incoming packet"));
616 /* Check the length of the buffer */
617 if (buffer->len < SILC_PACKET_MIN_LEN) {
618 SILC_LOG_ERROR(("Bad packet length: %d, packet dropped", buffer->len));
619 return SILC_PACKET_NONE;
622 /* Parse the buffer. This parses the SILC header of the packet. */
623 len = silc_buffer_unformat(buffer,
624 SILC_STR_UI_SHORT(&ctx->truelen),
625 SILC_STR_UI_CHAR(&ctx->flags),
626 SILC_STR_UI_CHAR(&ctx->type),
627 SILC_STR_UI_CHAR(&ctx->padlen),
628 SILC_STR_UI_CHAR(&tmp),
629 SILC_STR_UI_CHAR(&ctx->src_id_len),
630 SILC_STR_UI_CHAR(&ctx->dst_id_len),
631 SILC_STR_UI_CHAR(&ctx->src_id_type),
633 if (len == -1 || tmp != 0)
634 return SILC_PACKET_NONE;
636 if (ctx->src_id_len > SILC_PACKET_MAX_ID_LEN ||
637 ctx->dst_id_len > SILC_PACKET_MAX_ID_LEN) {
638 SILC_LOG_ERROR(("Bad ID lengths in packet (%d and %d)",
639 ctx->src_id_len, ctx->dst_id_len));
640 return SILC_PACKET_NONE;
643 silc_buffer_pull(buffer, len);
644 ret = silc_buffer_unformat(buffer,
645 SILC_STR_UI_XNSTRING_ALLOC(&ctx->src_id,
647 SILC_STR_UI_CHAR(&ctx->dst_id_type),
648 SILC_STR_UI_XNSTRING_ALLOC(&ctx->dst_id,
650 SILC_STR_UI_XNSTRING(NULL, ctx->padlen),
653 return SILC_PACKET_NONE;
655 silc_buffer_push(buffer, len);
657 SILC_LOG_HEXDUMP(("parsed packet, len %d", ctx->buffer->len),
658 ctx->buffer->data, ctx->buffer->len);
660 /* Pull SILC header and padding from packet */
661 silc_buffer_pull(buffer, SILC_PACKET_HEADER_LEN +
662 ctx->src_id_len + ctx->dst_id_len + ctx->padlen);
664 SILC_LOG_DEBUG(("Incoming packet type: %d", ctx->type));
669 /* Perform special SILC Packet header parsing. This is required to some
670 packet types that have the data payload encrypted with different key
671 than the header area plus padding of the packet. Hence, this parses
672 the header in a way that it does not take the data area into account
673 and parses the header and padding area only. */
675 SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx,
678 SilcBuffer buffer = ctx->buffer;
682 SILC_LOG_DEBUG(("Parsing incoming packet"));
684 /* Check the length of the buffer */
685 if (buffer->len < SILC_PACKET_MIN_LEN) {
686 SILC_LOG_ERROR(("Bad packet length: %d, packet dropped", buffer->len));
687 return SILC_PACKET_NONE;
690 /* Parse the buffer. This parses the SILC header of the packet. */
691 len = silc_buffer_unformat(buffer,
692 SILC_STR_UI_SHORT(&ctx->truelen),
693 SILC_STR_UI_CHAR(&ctx->flags),
694 SILC_STR_UI_CHAR(&ctx->type),
695 SILC_STR_UI_CHAR(&ctx->padlen),
696 SILC_STR_UI_CHAR(&tmp),
697 SILC_STR_UI_CHAR(&ctx->src_id_len),
698 SILC_STR_UI_CHAR(&ctx->dst_id_len),
699 SILC_STR_UI_CHAR(&ctx->src_id_type),
701 if (len == -1 || tmp != 0) {
702 SILC_LOG_ERROR(("Malformed packet header, packet dropped"));
703 return SILC_PACKET_NONE;
706 if (ctx->src_id_len > SILC_PACKET_MAX_ID_LEN ||
707 ctx->dst_id_len > SILC_PACKET_MAX_ID_LEN) {
708 SILC_LOG_ERROR(("Bad ID lengths in packet (%d and %d)",
709 ctx->src_id_len, ctx->dst_id_len));
710 return SILC_PACKET_NONE;
713 silc_buffer_pull(buffer, len);
714 ret = silc_buffer_unformat(buffer,
715 SILC_STR_UI_XNSTRING_ALLOC(&ctx->src_id,
717 SILC_STR_UI_CHAR(&ctx->dst_id_type),
718 SILC_STR_UI_XNSTRING_ALLOC(&ctx->dst_id,
720 SILC_STR_UI_XNSTRING(NULL, ctx->padlen),
723 SILC_LOG_ERROR(("Malformed packet header, packet dropped"));
724 return SILC_PACKET_NONE;
727 silc_buffer_push(buffer, len);
729 SILC_LOG_HEXDUMP(("parsed packet, len %d", ctx->buffer->len),
730 ctx->buffer->data, ctx->buffer->len);
732 /* Pull SILC header and padding from packet */
733 silc_buffer_pull(buffer, SILC_PACKET_HEADER_LEN +
734 ctx->src_id_len + ctx->dst_id_len + ctx->padlen);
736 SILC_LOG_DEBUG(("Incoming packet type: %d", ctx->type));
741 /* Allocate packet context */
743 SilcPacketContext *silc_packet_context_alloc(void)
745 SilcPacketContext *ctx = silc_calloc(1, sizeof(*ctx));
750 /* Increse the reference count of the packet context. */
752 SilcPacketContext *silc_packet_context_dup(SilcPacketContext *ctx)
755 SILC_LOG_DEBUG(("Packet context %p refcnt %d->%d", ctx, ctx->users - 1,
760 /* Decrese the reference count of the packet context and free it only if
763 void silc_packet_context_free(SilcPacketContext *ctx)
766 SILC_LOG_DEBUG(("Packet context %p refcnt %d->%d", ctx, ctx->users + 1,
771 silc_buffer_free(ctx->buffer);
773 silc_free(ctx->src_id);
775 silc_free(ctx->dst_id);