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;
335 int block_len = cipher ? silc_cipher_get_block_len(cipher) : 0;
338 if (sock->inbuf->len < SILC_PACKET_MIN_HEADER_LEN)
342 mac_len = silc_hmac_len(hmac);
344 /* Parse the packets from the data */
345 while (sock->inbuf->len > 0 && cont) {
347 if (sock->inbuf->len < SILC_PACKET_MIN_HEADER_LEN) {
348 SILC_LOG_DEBUG(("Partial packet in queue, waiting for the rest"));
352 /* Decrypt first 16 bytes of the packet */
353 if (!SILC_IS_INBUF_PENDING(sock) && cipher)
354 silc_cipher_decrypt(cipher, sock->inbuf->data, sock->inbuf->data,
355 SILC_PACKET_MIN_HEADER_LEN, cipher->iv);
357 /* Get packet lenght and full packet length with padding */
358 SILC_PACKET_LENGTH(sock->inbuf, packetlen, paddedlen);
361 if (packetlen < SILC_PACKET_MIN_LEN) {
362 SILC_LOG_DEBUG(("Received invalid packet, dropped"));
363 silc_buffer_clear(sock->inbuf);
367 if (sock->inbuf->len < paddedlen + mac_len) {
368 SILC_LOG_DEBUG(("Received partial packet, waiting for the rest"
369 "(%d < %d)", sock->inbuf->len, paddedlen + mac_len));
370 SILC_SET_INBUF_PENDING(sock);
374 SILC_UNSET_INBUF_PENDING(sock);
375 parse_ctx = silc_calloc(1, sizeof(*parse_ctx));
376 parse_ctx->packet = silc_packet_context_alloc();
377 parse_ctx->packet->buffer = silc_buffer_alloc(paddedlen + mac_len);
378 parse_ctx->packet->padlen = sock->inbuf->data[4];
379 parse_ctx->packet->sequence = sequence++;
380 parse_ctx->sock = sock;
381 parse_ctx->context = parser_context;
383 silc_buffer_pull_tail(parse_ctx->packet->buffer,
384 SILC_BUFFER_END(parse_ctx->packet->buffer));
385 silc_buffer_put(parse_ctx->packet->buffer, sock->inbuf->data,
386 paddedlen + mac_len);
388 SILC_LOG_HEXDUMP(("Incoming packet (%d) (%dB decrypted), len %d",
389 sequence - 1, block_len, paddedlen + mac_len),
390 sock->inbuf->data, paddedlen + mac_len);
392 /* Check whether this is normal or special packet */
393 if (local_is_router) {
394 if (sock->inbuf->data[3] == SILC_PACKET_PRIVATE_MESSAGE &&
395 (sock->inbuf->data[2] & SILC_PACKET_FLAG_PRIVMSG_KEY))
396 parse_ctx->normal = FALSE;
397 else if (sock->inbuf->data[3] != SILC_PACKET_CHANNEL_MESSAGE ||
398 (sock->inbuf->data[3] == SILC_PACKET_CHANNEL_MESSAGE &&
399 sock->type == SILC_SOCKET_TYPE_ROUTER))
400 parse_ctx->normal = TRUE;
402 if (sock->inbuf->data[3] == SILC_PACKET_PRIVATE_MESSAGE &&
403 (sock->inbuf->data[2] & SILC_PACKET_FLAG_PRIVMSG_KEY))
404 parse_ctx->normal = FALSE;
405 else if (sock->inbuf->data[3] != SILC_PACKET_CHANNEL_MESSAGE)
406 parse_ctx->normal = TRUE;
409 /* Decrypt rest of the packet */
411 if (silc_packet_decrypt(cipher, hmac, parse_ctx->packet->sequence,
412 parse_ctx->packet->buffer,
413 parse_ctx->normal) == -1) {
414 SILC_LOG_WARNING(("Packet decryption failed %s:%d [%s]",
415 sock->hostname, sock->port,
416 (sock->type == SILC_SOCKET_TYPE_UNKNOWN ? "Unknown" :
417 sock->type == SILC_SOCKET_TYPE_CLIENT ? "Client" :
418 sock->type == SILC_SOCKET_TYPE_SERVER ? "Server" :
422 /* Pull the packet from inbuf thus we'll get the next one
424 silc_buffer_pull(sock->inbuf, paddedlen + mac_len);
426 /* Call the parser */
427 cont = (*parser)(parse_ctx, parser_context);
430 if (cont == FALSE && sock->inbuf->len > 0)
433 SILC_LOG_DEBUG(("Clearing inbound buffer"));
434 silc_buffer_clear(sock->inbuf);
437 /* Checks MAC in the packet. Returns TRUE if MAC is Ok. This is called
438 after packet has been totally decrypted and parsed. */
440 static int silc_packet_check_mac(SilcHmac hmac, SilcBuffer buffer,
445 unsigned char mac[32], psn[4];
448 SILC_LOG_DEBUG(("Verifying MAC"));
450 /* Compute HMAC of packet */
452 memset(mac, 0, sizeof(mac));
453 silc_hmac_init(hmac);
454 SILC_PUT32_MSB(sequence, psn);
455 silc_hmac_update(hmac, psn, 4);
456 silc_hmac_update(hmac, buffer->data, buffer->len);
457 silc_hmac_final(hmac, mac, &mac_len);
459 /* Compare the HMAC's (buffer->tail has the packet's HMAC) */
460 if (memcmp(mac, buffer->tail, mac_len)) {
461 SILC_LOG_ERROR(("MAC failed"));
465 SILC_LOG_DEBUG(("MAC is Ok"));
466 memset(mac, 0, sizeof(mac));
472 /* Decrypts rest of the packet (after decrypting just the SILC header).
473 After calling this function the packet is ready to be parsed by calling
474 silc_packet_parse. If everything goes without errors this returns TRUE,
475 if packet is malformed this returns FALSE. */
477 static int silc_packet_decrypt_rest(SilcCipher cipher, SilcHmac hmac,
482 /* Pull MAC from packet before decryption */
484 if ((buffer->len - silc_hmac_len(hmac)) > SILC_PACKET_MIN_LEN) {
485 silc_buffer_push_tail(buffer, silc_hmac_len(hmac));
487 SILC_LOG_DEBUG(("Bad MAC length in packet, packet dropped"));
492 SILC_LOG_DEBUG(("Decrypting rest of the packet"));
494 /* Decrypt rest of the packet */
495 silc_buffer_pull(buffer, SILC_PACKET_MIN_HEADER_LEN);
496 silc_cipher_decrypt(cipher, buffer->data, buffer->data, buffer->len,
498 silc_buffer_push(buffer, SILC_PACKET_MIN_HEADER_LEN);
500 SILC_LOG_HEXDUMP(("Fully decrypted packet, len %d", buffer->len),
501 buffer->data, buffer->len);
507 /* Decrypts rest of the SILC Packet header that has been decrypted partly
508 already. This decrypts the padding of the packet also. After calling
509 this function the packet is ready to be parsed by calling function
510 silc_packet_parse. This is used in special packet reception (protocol
511 defines the way of decrypting special packets). */
513 static int silc_packet_decrypt_rest_special(SilcCipher cipher,
517 /* Decrypt rest of the header plus padding */
521 /* Pull MAC from packet before decryption */
523 if ((buffer->len - silc_hmac_len(hmac)) > SILC_PACKET_MIN_LEN) {
524 silc_buffer_push_tail(buffer, silc_hmac_len(hmac));
526 SILC_LOG_DEBUG(("Bad MAC length in packet, packet dropped"));
531 SILC_LOG_DEBUG(("Decrypting rest of the header"));
533 /* padding length + src id len + dst id len + header length - 16
534 bytes already decrypted, gives the rest of the encrypted packet */
535 len = (((uint8)buffer->data[4] + (uint8)buffer->data[6] +
536 (uint8)buffer->data[7] + SILC_PACKET_HEADER_LEN) -
537 SILC_PACKET_MIN_HEADER_LEN);
539 silc_buffer_pull(buffer, SILC_PACKET_MIN_HEADER_LEN);
540 if (len > buffer->len) {
541 SILC_LOG_DEBUG(("Garbage in header of packet, bad packet length, "
545 silc_cipher_decrypt(cipher, buffer->data, buffer->data, len, cipher->iv);
546 silc_buffer_push(buffer, SILC_PACKET_MIN_HEADER_LEN);
547 SILC_LOG_HEXDUMP(("packet, len %d", buffer->len),
548 buffer->data, buffer->len);
554 /* Decrypts a packet. This assumes that typical SILC packet is the
555 packet to be decrypted and thus checks for normal and special SILC
556 packets and can handle both of them. This also computes and checks
557 the HMAC of the packet. If any other special or customized decryption
558 processing is required this function cannot be used. This returns
559 -1 on error, 0 when packet is normal packet and 1 when the packet
560 is special and requires special processing.
562 The `check_packet' is a callback funtion that this function will
563 call. The callback relates to the checking whether the packet is
564 normal packet or special packet and how it should be processed. If
565 the callback return TRUE the packet is normal and FALSE if the packet
566 is special and requires special procesing. */
568 static int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
569 uint32 sequence, SilcBuffer buffer,
572 /* If the packet type is not any special type lets decrypt rest
573 of the packet here. */
574 if (normal == TRUE) {
575 /* Normal packet, decrypt rest of the packet */
576 if (!silc_packet_decrypt_rest(cipher, hmac, buffer))
580 if (!silc_packet_check_mac(hmac, buffer, sequence))
585 /* Packet requires special handling, decrypt rest of the header.
586 This only decrypts. */
587 if (!silc_packet_decrypt_rest_special(cipher, hmac, buffer))
591 if (!silc_packet_check_mac(hmac, buffer, sequence))
598 /* Parses the packet. This is called when a whole packet is ready to be
599 parsed. The buffer sent must be already decrypted before calling this
600 function. The len argument must be the true length of the packet. This
601 function returns the type of the packet. The data section of the
602 buffer is parsed, not head or tail sections. */
604 SilcPacketType silc_packet_parse(SilcPacketContext *ctx, SilcCipher cipher)
606 SilcBuffer buffer = ctx->buffer;
610 SILC_LOG_DEBUG(("Parsing incoming packet"));
612 /* Check the length of the buffer */
613 if (buffer->len < SILC_PACKET_MIN_LEN) {
614 SILC_LOG_ERROR(("Bad packet length: %d, packet dropped", buffer->len));
615 return SILC_PACKET_NONE;
618 /* Parse the buffer. This parses the SILC header of the packet. */
619 len = silc_buffer_unformat(buffer,
620 SILC_STR_UI_SHORT(&ctx->truelen),
621 SILC_STR_UI_CHAR(&ctx->flags),
622 SILC_STR_UI_CHAR(&ctx->type),
623 SILC_STR_UI_CHAR(&ctx->padlen),
624 SILC_STR_UI_CHAR(&tmp),
625 SILC_STR_UI_CHAR(&ctx->src_id_len),
626 SILC_STR_UI_CHAR(&ctx->dst_id_len),
627 SILC_STR_UI_CHAR(&ctx->src_id_type),
629 if (len == -1 || tmp != 0)
630 return SILC_PACKET_NONE;
632 if (ctx->src_id_len > SILC_PACKET_MAX_ID_LEN ||
633 ctx->dst_id_len > SILC_PACKET_MAX_ID_LEN) {
634 SILC_LOG_ERROR(("Bad ID lengths in packet (%d and %d)",
635 ctx->src_id_len, ctx->dst_id_len));
636 return SILC_PACKET_NONE;
639 silc_buffer_pull(buffer, len);
640 ret = silc_buffer_unformat(buffer,
641 SILC_STR_UI_XNSTRING_ALLOC(&ctx->src_id,
643 SILC_STR_UI_CHAR(&ctx->dst_id_type),
644 SILC_STR_UI_XNSTRING_ALLOC(&ctx->dst_id,
646 SILC_STR_UI_XNSTRING(NULL, ctx->padlen),
649 return SILC_PACKET_NONE;
651 silc_buffer_push(buffer, len);
653 SILC_LOG_HEXDUMP(("parsed packet, len %d", ctx->buffer->len),
654 ctx->buffer->data, ctx->buffer->len);
656 /* Pull SILC header and padding from packet */
657 silc_buffer_pull(buffer, SILC_PACKET_HEADER_LEN +
658 ctx->src_id_len + ctx->dst_id_len + ctx->padlen);
660 SILC_LOG_DEBUG(("Incoming packet type: %d", ctx->type));
665 /* Perform special SILC Packet header parsing. This is required to some
666 packet types that have the data payload encrypted with different key
667 than the header area plus padding of the packet. Hence, this parses
668 the header in a way that it does not take the data area into account
669 and parses the header and padding area only. */
671 SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx,
674 SilcBuffer buffer = ctx->buffer;
678 SILC_LOG_DEBUG(("Parsing incoming packet"));
680 /* Check the length of the buffer */
681 if (buffer->len < SILC_PACKET_MIN_LEN) {
682 SILC_LOG_ERROR(("Bad packet length: %d, packet dropped", buffer->len));
683 return SILC_PACKET_NONE;
686 /* Parse the buffer. This parses the SILC header of the packet. */
687 len = silc_buffer_unformat(buffer,
688 SILC_STR_UI_SHORT(&ctx->truelen),
689 SILC_STR_UI_CHAR(&ctx->flags),
690 SILC_STR_UI_CHAR(&ctx->type),
691 SILC_STR_UI_CHAR(&ctx->padlen),
692 SILC_STR_UI_CHAR(&tmp),
693 SILC_STR_UI_CHAR(&ctx->src_id_len),
694 SILC_STR_UI_CHAR(&ctx->dst_id_len),
695 SILC_STR_UI_CHAR(&ctx->src_id_type),
697 if (len == -1 || tmp != 0) {
698 SILC_LOG_ERROR(("Malformed packet header, packet dropped"));
699 return SILC_PACKET_NONE;
702 if (ctx->src_id_len > SILC_PACKET_MAX_ID_LEN ||
703 ctx->dst_id_len > SILC_PACKET_MAX_ID_LEN) {
704 SILC_LOG_ERROR(("Bad ID lengths in packet (%d and %d)",
705 ctx->src_id_len, ctx->dst_id_len));
706 return SILC_PACKET_NONE;
709 silc_buffer_pull(buffer, len);
710 ret = silc_buffer_unformat(buffer,
711 SILC_STR_UI_XNSTRING_ALLOC(&ctx->src_id,
713 SILC_STR_UI_CHAR(&ctx->dst_id_type),
714 SILC_STR_UI_XNSTRING_ALLOC(&ctx->dst_id,
716 SILC_STR_UI_XNSTRING(NULL, ctx->padlen),
719 SILC_LOG_ERROR(("Malformed packet header, packet dropped"));
720 return SILC_PACKET_NONE;
723 silc_buffer_push(buffer, len);
725 SILC_LOG_HEXDUMP(("parsed packet, len %d", ctx->buffer->len),
726 ctx->buffer->data, ctx->buffer->len);
728 /* Pull SILC header and padding from packet */
729 silc_buffer_pull(buffer, SILC_PACKET_HEADER_LEN +
730 ctx->src_id_len + ctx->dst_id_len + ctx->padlen);
732 SILC_LOG_DEBUG(("Incoming packet type: %d", ctx->type));
737 /* Allocate packet context */
739 SilcPacketContext *silc_packet_context_alloc(void)
741 SilcPacketContext *ctx = silc_calloc(1, sizeof(*ctx));
746 /* Increse the reference count of the packet context. */
748 SilcPacketContext *silc_packet_context_dup(SilcPacketContext *ctx)
751 SILC_LOG_DEBUG(("Packet context %p refcnt %d->%d", ctx, ctx->users - 1,
756 /* Decrese the reference count of the packet context and free it only if
759 void silc_packet_context_free(SilcPacketContext *ctx)
762 SILC_LOG_DEBUG(("Packet context %p refcnt %d->%d", ctx, ctx->users + 1,
767 silc_buffer_free(ctx->buffer);
769 silc_free(ctx->src_id);
771 silc_free(ctx->dst_id);