5 Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
7 Copyright (C) 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 /* This file includes the Key Agreement packet processing and actual
22 key agreement routines. This file has nothing to do with the actual
23 connection key exchange protocol, it is implemented in the client.c
24 and in protocol.c. This file implements the client-to-client key
25 agreement as defined by the SILC protocol. */
27 #include "silcincludes.h"
28 #include "silcclient.h"
29 #include "client_internal.h"
31 SILC_TASK_CALLBACK(silc_client_key_agreement_final);
32 SILC_TASK_CALLBACK(silc_client_process_key_agreement);
33 SILC_TASK_CALLBACK(silc_client_key_agreement_timeout);
34 SILC_TASK_CALLBACK(silc_client_perform_key_agreement_start);
36 /* Key agreement context */
37 struct SilcClientKeyAgreementStruct {
39 SilcClientConnection conn;
40 int fd; /* Listening/connection socket */
41 SilcSocketConnection sock; /* Remote socket connection */
42 SilcClientEntry client_entry; /* Destination client */
43 SilcKeyAgreementCallback completion; /* Key agreement completion */
44 void *context; /* User context */
45 SilcTask timeout; /* Timeout task */
46 SilcClientKEInternalContext *proto_ctx; /* Key Exchange protocol context */
49 /* Packet sending function used by the SKE in the key agreement process. */
51 static void silc_client_key_agreement_send_packet(SilcSKE ske,
56 SilcProtocol protocol = (SilcProtocol)context;
57 SilcClientKEInternalContext *ctx =
58 (SilcClientKEInternalContext *)protocol->context;
61 /* Send the packet immediately. We will assure that the packet is not
62 encrypted by setting the socket's user_data pointer to NULL. The
63 silc_client_packet_send would take the keys (wrong keys that is,
64 because user_data is the current SilcClientConnection) from it and
65 we cannot allow that. The packets are never encrypted when doing SKE
66 with another client. */
67 tmp = ske->sock->user_data;
68 ske->sock->user_data = NULL;
69 silc_client_packet_send(ctx->client, ske->sock, type, NULL, 0, NULL, NULL,
70 packet->data, packet->len, TRUE);
71 ske->sock->user_data = tmp;
74 /* Timeout callback that is called to close the connection and free the
75 socket connection data. */
77 SILC_TASK_CALLBACK(silc_client_key_agreement_close)
79 SilcClientKeyAgreement ke = (SilcClientKeyAgreement)context;
81 silc_schedule_unset_listen_fd(ke->client->schedule, ke->sock->sock);
82 silc_schedule_unset_listen_fd(ke->client->schedule, ke->fd);
83 silc_net_close_connection(ke->sock->sock);
84 silc_net_close_connection(ke->fd);
85 silc_socket_free(ke->sock);
89 /* This callback is called after the key agreement protocol has been
90 performed. This calls the final completion callback for the application. */
92 SILC_TASK_CALLBACK(silc_client_key_agreement_final)
94 SilcProtocol protocol = (SilcProtocol)context;
95 SilcClientKEInternalContext *ctx =
96 (SilcClientKEInternalContext *)protocol->context;
97 SilcClient client = (SilcClient)ctx->client;
98 SilcClientKeyAgreement ke = (SilcClientKeyAgreement)ctx->context;
100 SILC_LOG_DEBUG(("Start"));
102 if (protocol->state == SILC_PROTOCOL_STATE_ERROR ||
103 protocol->state == SILC_PROTOCOL_STATE_FAILURE) {
104 /* Error occured during protocol */
105 ke->client_entry->ke = NULL;
106 ke->completion(ke->client, ke->conn, ke->client_entry,
107 SILC_KEY_AGREEMENT_ERROR, NULL, ke->context);
108 silc_ske_free_key_material(ctx->keymat);
112 /* Pass the negotiated key material to the application. The application
113 is responsible of freeing the key material. */
114 ke->client_entry->ke = NULL;
115 ke->completion(ke->client, ke->conn, ke->client_entry,
116 SILC_KEY_AGREEMENT_OK, ctx->keymat, ke->context);
119 silc_protocol_free(protocol);
121 silc_ske_free(ctx->ske);
123 silc_free(ctx->dest_id);
124 silc_schedule_task_del_by_fd(client->schedule, ke->fd);
125 silc_schedule_unset_listen_fd(ke->client->schedule, ke->fd);
126 silc_net_close_connection(ke->fd);
128 silc_schedule_task_del(client->schedule, ke->timeout);
129 silc_client_del_socket(ke->client, ke->sock);
131 silc_schedule_task_add(client->schedule, 0,
132 silc_client_key_agreement_close,
134 SILC_TASK_TIMEOUT, SILC_TASK_PRI_NORMAL);
139 /* Key agreement callback that is called when remote end has initiated
140 the key agreement protocol. This accepts the incoming TCP/IP connection
141 for the key agreement protocol. */
143 SILC_TASK_CALLBACK(silc_client_process_key_agreement)
145 SilcClientKeyAgreement ke = (SilcClientKeyAgreement)context;
146 SilcClient client = ke->client;
147 SilcClientConnection conn = ke->conn;
148 SilcSocketConnection newsocket;
149 SilcClientKEInternalContext *proto_ctx;
152 SILC_LOG_DEBUG(("Start"));
154 sock = silc_net_accept_connection(ke->fd);
156 client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT,
157 "Could not accept key agreement connection: ",
159 ke->client_entry->ke = NULL;
160 ke->completion(ke->client, ke->conn, ke->client_entry,
161 SILC_KEY_AGREEMENT_ERROR, NULL, ke->context);
162 silc_schedule_task_del_by_fd(client->schedule, ke->fd);
163 silc_schedule_unset_listen_fd(ke->client->schedule, ke->fd);
164 silc_net_close_connection(ke->fd);
166 silc_schedule_task_del(client->schedule, ke->timeout);
171 /* Set socket options */
172 silc_net_set_socket_nonblock(sock);
173 silc_net_set_socket_opt(sock, SOL_SOCKET, SO_REUSEADDR, 1);
175 /* Create socket for this connection (it is of type UNKNOWN since this
176 really is not a real SILC connection. It is only for the key
177 agreement protocol). */
178 silc_socket_alloc(sock, SILC_SOCKET_TYPE_UNKNOWN, (void *)conn, &newsocket);
179 ke->sock = newsocket;
181 /* Perform name and address lookups for the remote host. */
182 silc_net_check_host_by_sock(sock, &newsocket->hostname, &newsocket->ip);
183 if (!newsocket->hostname && !newsocket->ip) {
184 client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT,
185 "Could not resolve the remote IP or hostname");
186 ke->client_entry->ke = NULL;
187 ke->completion(ke->client, ke->conn, ke->client_entry,
188 SILC_KEY_AGREEMENT_ERROR, NULL, ke->context);
189 silc_schedule_task_del_by_fd(client->schedule, ke->fd);
190 silc_schedule_unset_listen_fd(ke->client->schedule, ke->fd);
191 silc_net_close_connection(ke->fd);
193 silc_schedule_task_del(client->schedule, ke->timeout);
197 if (!newsocket->hostname)
198 newsocket->hostname = strdup(newsocket->ip);
199 newsocket->port = silc_net_get_remote_port(sock);
200 silc_client_add_socket(client, newsocket);
202 /* Allocate internal context for key exchange protocol. This is
203 sent as context for the protocol. */
204 proto_ctx = silc_calloc(1, sizeof(*proto_ctx));
205 proto_ctx->client = client;
206 proto_ctx->sock = silc_socket_dup(newsocket);
207 proto_ctx->rng = client->rng;
208 proto_ctx->responder = TRUE;
209 proto_ctx->context = context;
210 proto_ctx->send_packet = silc_client_key_agreement_send_packet;
211 proto_ctx->verify = silc_client_protocol_ke_verify_key;
212 ke->proto_ctx = proto_ctx;
214 /* Prepare the connection for key exchange protocol. We allocate the
215 protocol but will not start it yet. The connector will be the
216 initiator of the protocol thus we will wait for initiation from
217 there before we start the protocol. */
218 silc_protocol_alloc(SILC_PROTOCOL_CLIENT_KEY_EXCHANGE,
219 &newsocket->protocol, proto_ctx,
220 silc_client_key_agreement_final);
222 /* Register the connection for network input and output. This sets
223 that scheduler will listen for incoming packets for this connection
224 and sets that outgoing packets may be sent to this connection as well.
225 However, this doesn't set the scheduler for outgoing traffic, it
226 will be set separately by calling SILC_CLIENT_SET_CONNECTION_FOR_OUTPUT,
227 later when outgoing data is available. */
228 context = (void *)client;
229 SILC_CLIENT_REGISTER_CONNECTION_FOR_IO(sock);
232 /* Timeout occured during key agreement. This means that the key agreement
233 protocol was not completed in the specified timeout. We will call the
234 completion callback. */
236 SILC_TASK_CALLBACK(silc_client_key_agreement_timeout)
238 SilcClientKeyAgreement ke = (SilcClientKeyAgreement)context;
240 ke->client_entry->ke = NULL;
241 ke->completion(ke->client, ke->conn, ke->client_entry,
242 SILC_KEY_AGREEMENT_TIMEOUT, NULL, ke->context);
245 silc_client_del_socket(ke->client, ke->sock);
246 silc_socket_free(ke->sock);
248 if (ke->proto_ctx && ke->proto_ctx->ske)
249 silc_ske_free(ke->proto_ctx->ske);
250 ke->client_entry->ke = NULL;
252 silc_schedule_task_del_by_fd(ke->client->schedule, ke->fd);
253 silc_schedule_unset_listen_fd(ke->client->schedule, ke->fd);
254 silc_net_close_connection(ke->fd);
258 /* Sends key agreement request to the remote client indicated by the
259 `client_entry'. If the caller provides the `hostname' and the `port'
260 arguments then the library will bind the client to that hostname and
261 that port for the key agreement protocol. It also sends the `hostname'
262 and the `port' in the key agreement packet to the remote client. This
263 would indicate that the remote client may initiate the key agreement
264 protocol to the `hostname' on the `port'. If port is zero then the
265 bound port is undefined (the operating system defines it).
267 If the `hostname' and `port' is not provided then empty key agreement
268 packet is sent to the remote client. The remote client may reply with
269 the same packet including its hostname and port. If the library receives
270 the reply from the remote client the `key_agreement' client operation
271 callback will be called to verify whether the user wants to perform the
272 key agreement or not.
274 NOTE: If the application provided the `hostname' and the `port' and the
275 remote side initiates the key agreement protocol it is not verified
276 from the user anymore whether the protocol should be executed or not.
277 By setting the `hostname' and `port' the user gives permission to
278 perform the protocol (we are responder in this case).
280 NOTE: If the remote side decides not to initiate the key agreement
281 or decides not to reply with the key agreement packet then we cannot
282 perform the key agreement at all. If the key agreement protocol is
283 performed the `completion' callback with the `context' will be called.
284 If remote side decides to ignore the request the `completion' will be
285 called after the specified timeout, `timeout_secs'.
287 NOTE: If the `hostname' and the `port' was not provided the `completion'
288 will not be called at all since this does nothing more than sending
289 a packet to the remote host.
291 NOTE: There can be only one active key agreement for one client entry.
292 Before setting new one, the old one must be finished (it is finished
293 after calling the completion callback) or the function
294 silc_client_abort_key_agreement must be called. */
296 void silc_client_send_key_agreement(SilcClient client,
297 SilcClientConnection conn,
298 SilcClientEntry client_entry,
299 const char *hostname,
300 const char *bindhost,
302 SilcUInt32 timeout_secs,
303 SilcKeyAgreementCallback completion,
306 SilcSocketConnection sock = conn->sock;
307 SilcClientKeyAgreement ke = NULL;
313 if (client_entry->ke) {
314 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_ALREADY_STARTED,
319 if (client_entry == conn->local_entry) {
320 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_SELF_DENIED,
325 /* Create the listener if hostname and port was provided.
326 * also, use bindhost if it was specified.
330 ke = silc_calloc(1, sizeof(*ke));
333 ke->fd = silc_net_create_server(port, bindhost);
335 ke->fd = silc_net_create_server(port, hostname);
338 client->internal->ops->say(
339 client, conn, SILC_CLIENT_MESSAGE_ERROR,
340 "Cannot create listener on %s on port %d: %s",
341 (bindhost) ? bindhost:hostname, port, strerror(errno));
342 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_FAILURE,
350 ke->client_entry = client_entry;
351 ke->completion = completion;
352 ke->context = context;
354 /* Add listener task to the scheduler. This task receives the key
356 silc_schedule_task_add(client->schedule, ke->fd,
357 silc_client_process_key_agreement,
360 SILC_TASK_PRI_NORMAL);
362 /* Register a timeout task that will be executed if the connector
363 will not start the key exchange protocol within the specified
365 ke->timeout = silc_schedule_task_add(client->schedule, 0,
366 silc_client_key_agreement_timeout,
367 (void *)ke, timeout_secs, 0,
368 SILC_TASK_TIMEOUT, SILC_TASK_PRI_LOW);
371 /* Encode the key agreement payload */
372 buffer = silc_key_agreement_payload_encode(hostname,
374 silc_net_get_local_port(ke->fd));
376 /* Send the key agreement packet to the client */
377 silc_client_packet_send(client, sock, SILC_PACKET_KEY_AGREEMENT,
378 client_entry->id, SILC_ID_CLIENT, NULL, NULL,
379 buffer->data, buffer->len, FALSE);
380 silc_buffer_free(buffer);
384 silc_client_connect_to_client_internal(SilcClientInternalConnectContext *ctx)
388 /* Create connection to server asynchronously */
389 sock = silc_net_create_connection_async(NULL, ctx->port, ctx->host);
393 /* Register task that will receive the async connect and will
395 ctx->task = silc_schedule_task_add(ctx->client->schedule, sock,
396 silc_client_perform_key_agreement_start,
399 SILC_TASK_PRI_NORMAL);
400 silc_schedule_set_listen_fd(ctx->client->schedule, sock, SILC_TASK_WRITE);
407 /* Routine used by silc_client_perform_key_agreement to create connection
408 to the remote client on specified port. */
411 silc_client_connect_to_client(SilcClient client,
412 SilcClientConnection conn, int port,
413 char *host, void *context)
415 SilcClientInternalConnectContext *ctx;
417 /* Allocate internal context for connection process. This is
418 needed as we are doing async connecting. */
419 ctx = silc_calloc(1, sizeof(*ctx));
420 ctx->client = client;
422 ctx->host = strdup(host);
425 ctx->context = context;
427 /* Do the actual connecting process */
428 return silc_client_connect_to_client_internal(ctx);
431 /* Callback that is called after connection has been created. This actually
432 starts the key agreement protocol. This is initiator function. */
434 SILC_TASK_CALLBACK(silc_client_perform_key_agreement_start)
436 SilcClientInternalConnectContext *ctx =
437 (SilcClientInternalConnectContext *)context;
438 SilcClient client = ctx->client;
439 SilcClientConnection conn = ctx->conn;
440 SilcClientKeyAgreement ke = (SilcClientKeyAgreement)ctx->context;
441 int opt, opt_len = sizeof(opt);
443 SILC_LOG_DEBUG(("Start"));
445 /* Check the socket status as it might be in error */
446 silc_net_get_socket_opt(fd, SOL_SOCKET, SO_ERROR, &opt, &opt_len);
448 if (ctx->tries < 2) {
449 /* Connection failed but lets try again */
450 client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_ERROR,
451 "Could not connect to client %s: %s",
452 ctx->host, strerror(opt));
453 client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT,
454 "Connecting to port %d of client %s resumed",
455 ctx->port, ctx->host);
457 /* Unregister old connection try */
458 silc_schedule_unset_listen_fd(client->schedule, fd);
459 silc_net_close_connection(fd);
460 silc_schedule_task_del(client->schedule, ctx->task);
463 silc_client_connect_to_client_internal(ctx);
466 /* Connection failed and we won't try anymore */
467 client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_ERROR,
468 "Could not connect to client %s: %s",
469 ctx->host, strerror(opt));
470 silc_schedule_unset_listen_fd(client->schedule, fd);
471 silc_net_close_connection(fd);
472 silc_schedule_task_del(client->schedule, ctx->task);
473 silc_free(ctx->host);
476 /* Call the completion callback */
477 ke->completion(ke->client, ke->conn, ke->client_entry,
478 SILC_KEY_AGREEMENT_FAILURE, NULL, ke->context);
484 silc_schedule_unset_listen_fd(client->schedule, fd);
485 silc_schedule_task_del(client->schedule, ctx->task);
489 /* Now actually perform the key agreement protocol */
490 silc_client_perform_key_agreement_fd(ke->client, ke->conn,
491 ke->client_entry, ke->fd, ctx->host,
492 ke->completion, ke->context);
494 silc_free(ctx->host);
498 /* Performs the actual key agreement protocol. Application may use this
499 to initiate the key agreement protocol. This can be called for example
500 after the application has received the `key_agreement' client operation,
501 and did not return TRUE from it.
503 The `hostname' is the remote hostname (or IP address) and the `port'
504 is the remote port. The `completion' callback with the `context' will
505 be called after the key agreement protocol.
507 NOTE: If the application returns TRUE in the `key_agreement' client
508 operation the library will automatically start the key agreement. In this
509 case the application must not call this function. However, application
510 may choose to just ignore the `key_agreement' client operation (and
511 merely just print information about it on the screen) and call this
512 function when the user whishes to do so (by, for example, giving some
513 specific command). Thus, the API provides both, automatic and manual
514 initiation of the key agreement. Calling this function is the manual
515 initiation and returning TRUE in the `key_agreement' client operation
516 is the automatic initiation. */
518 void silc_client_perform_key_agreement(SilcClient client,
519 SilcClientConnection conn,
520 SilcClientEntry client_entry,
523 SilcKeyAgreementCallback completion,
526 SilcClientKeyAgreement ke;
528 SILC_LOG_DEBUG(("Start"));
533 if (!hostname || !port) {
534 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_FAILURE,
539 if (client_entry == conn->local_entry) {
540 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_SELF_DENIED,
545 ke = silc_calloc(1, sizeof(*ke));
548 ke->client_entry = client_entry;
549 ke->completion = completion;
550 ke->context = context;
552 /* Connect to the remote client */
553 ke->fd = silc_client_connect_to_client(client, conn, port, hostname, ke);
555 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_FAILURE,
562 /* Same as above but application has created already the connection to
563 the remote host. The `sock' is the socket to the remote connection.
564 Application can use this function if it does not want the client library
565 to create the connection. */
567 void silc_client_perform_key_agreement_fd(SilcClient client,
568 SilcClientConnection conn,
569 SilcClientEntry client_entry,
572 SilcKeyAgreementCallback completion,
575 SilcClientKeyAgreement ke;
576 SilcClientKEInternalContext *proto_ctx;
577 SilcProtocol protocol;
579 SILC_LOG_DEBUG(("Start"));
584 if (client_entry == conn->local_entry) {
585 completion(client, conn, client_entry, SILC_KEY_AGREEMENT_SELF_DENIED,
590 ke = silc_calloc(1, sizeof(*ke));
593 ke->client_entry = client_entry;
595 ke->completion = completion;
596 ke->context = context;
598 /* Allocate new socket connection object */
599 silc_socket_alloc(sock, SILC_SOCKET_TYPE_UNKNOWN, (void *)conn, &ke->sock);
600 silc_client_add_socket(client, ke->sock);
601 ke->sock->hostname = strdup(hostname);
602 ke->sock->port = silc_net_get_remote_port(sock);
604 /* Allocate internal context for key exchange protocol. This is
605 sent as context for the protocol. */
606 proto_ctx = silc_calloc(1, sizeof(*proto_ctx));
607 proto_ctx->client = client;
608 proto_ctx->sock = silc_socket_dup(ke->sock);
609 proto_ctx->rng = client->rng;
610 proto_ctx->responder = FALSE;
611 proto_ctx->context = ke;
612 proto_ctx->send_packet = silc_client_key_agreement_send_packet;
613 proto_ctx->verify = silc_client_protocol_ke_verify_key;
614 ke->proto_ctx = proto_ctx;
616 /* Perform key exchange protocol. */
617 silc_protocol_alloc(SILC_PROTOCOL_CLIENT_KEY_EXCHANGE,
618 &protocol, (void *)proto_ctx,
619 silc_client_key_agreement_final);
620 ke->sock->protocol = protocol;
622 /* Register the connection for network input and output. This sets
623 that scheduler will listen for incoming packets for this connection
624 and sets that outgoing packets may be sent to this connection as well.
625 However, this doesn't set the scheduler for outgoing traffic, it will
626 be set separately by calling SILC_CLIENT_SET_CONNECTION_FOR_OUTPUT,
627 later when outgoing data is available. */
628 context = (void *)client;
629 SILC_CLIENT_REGISTER_CONNECTION_FOR_IO(sock);
631 /* Execute the protocol */
632 silc_protocol_execute(protocol, client->schedule, 0, 0);
635 /* This function can be called to unbind the hostname and the port for
636 the key agreement protocol. However, this function has effect only
637 before the key agreement protocol has been performed. After it has
638 been performed the library will automatically unbind the port. The
639 `client_entry' is the client to which we sent the key agreement
642 void silc_client_abort_key_agreement(SilcClient client,
643 SilcClientConnection conn,
644 SilcClientEntry client_entry)
649 if (client_entry->ke) {
650 SilcClientKeyAgreement ke;
652 if (client_entry->ke->sock) {
653 silc_client_del_socket(client_entry->ke->client, client_entry->ke->sock);
654 silc_socket_free(client_entry->ke->sock);
656 silc_schedule_task_del_by_fd(client->schedule, client_entry->ke->fd);
657 if (client_entry->ke->timeout)
658 silc_schedule_task_del(client->schedule,
659 client_entry->ke->timeout);
660 ke = client_entry->ke;
661 client_entry->ke = NULL;
662 ke->completion(client, conn, client_entry,
663 SILC_KEY_AGREEMENT_ABORTED, NULL, ke->context);
668 /* Callback function that is called after we've resolved the client
669 information who sent us the key agreement packet from the server.
670 We actually call the key_agreement client operation now. */
673 silc_client_key_agreement_resolve_cb(SilcClient client,
674 SilcClientConnection conn,
675 SilcClientEntry *clients,
676 SilcUInt32 clients_count,
679 SilcPacketContext *packet = (SilcPacketContext *)context;
680 SilcKeyAgreementPayload payload;
682 SilcKeyAgreementCallback completion;
683 void *completion_context;
688 /* Parse the key agreement payload */
689 payload = silc_key_agreement_payload_parse(packet->buffer->data,
690 packet->buffer->len);
694 /* Call the key_agreement client operation */
695 ret = client->internal->ops->key_agreement(
696 client, conn, clients[0],
697 silc_key_agreement_get_hostname(payload),
698 silc_key_agreement_get_port(payload),
699 &completion, &completion_context);
701 /* If the user returned TRUE then we'll start the key agreement right
702 here and right now. */
704 silc_client_perform_key_agreement(client, conn, clients[0],
705 silc_key_agreement_get_hostname(payload),
706 silc_key_agreement_get_port(payload),
707 completion, completion_context);
709 silc_key_agreement_payload_free(payload);
712 silc_packet_context_free(packet);
715 /* Received Key Agreement packet from remote client. Process the packet
716 and resolve the client information from the server before actually
717 letting the application know that we've received this packet. Then
718 call the key_agreement client operation and let the user decide
719 whether we perform the key agreement protocol now or not. */
721 void silc_client_key_agreement(SilcClient client,
722 SilcSocketConnection sock,
723 SilcPacketContext *packet)
725 SilcClientID *remote_id;
727 if (packet->src_id_type != SILC_ID_CLIENT)
730 remote_id = silc_id_str2id(packet->src_id, packet->src_id_len,
735 silc_client_get_client_by_id_resolve(client, sock->user_data, remote_id,
736 silc_client_key_agreement_resolve_cb,
737 silc_packet_context_dup(packet));
738 silc_free(remote_id);