5 Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
7 Copyright (C) 2000 - 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.
24 #include "clientlibincludes.h"
27 This file defines the SILC Client Library API for the application. The
28 client operations are defined first. These are callback functions that
29 the application MUST implement since the library may call the functions
30 at any time. At the end of file is the API for the application that
31 it can use from the library. This is the only file that the application
32 may include from the SIlC Client Library.
34 Please, refer to the README file in this directory for the directions
35 of how to use the SILC Client Library.
38 /* General definitions */
40 /* Key agreement status types indicating the status of the protocol. */
42 SILC_KEY_AGREEMENT_OK, /* Everything is Ok */
43 SILC_KEY_AGREEMENT_ERROR, /* Unknown error occured */
44 SILC_KEY_AGREEMENT_FAILURE, /* The protocol failed */
45 SILC_KEY_AGREEMENT_TIMEOUT, /* The protocol timeout */
46 } SilcKeyAgreementStatus;
48 /* Key agreement callback that is called after the key agreement protocol
49 has been performed. This is called also if error occured during the
50 key agreement protocol. The `key' is the allocated key material and
51 the caller is responsible of freeing it. The `key' is NULL if error
52 has occured. The application can freely use the `key' to whatever
53 purpose it needs. See lib/silcske/silcske.h for the definition of
54 the SilcSKEKeyMaterial structure. */
55 typedef void (*SilcKeyAgreementCallback)(SilcClient client,
56 SilcClientConnection conn,
57 SilcClientEntry client_entry,
58 SilcKeyAgreementStatus status,
59 SilcSKEKeyMaterial *key,
62 /* Structure to hold the list of private message keys. The array of this
63 structure is returned by the silc_client_list_private_message_keys
66 SilcClientEntry client_entry; /* The remote client entry */
67 char *cipher; /* The cipher name */
68 unsigned char *key; /* The original key, If the appliation
69 provided it. This is NULL if the
70 library generated the key or if
71 the SKE key material was used. */
72 unsigned int key_len; /* The key length */
73 } *SilcPrivateMessageKeys;
75 /******************************************************************************
77 SILC Client Operations
79 These functions must be implemented by the application calling the SILC
80 client library. The client library can call these functions at any time.
82 To use this structure: define a static SilcClientOperations variable,
83 fill it and pass its pointer to silc_client_alloc function.
85 ******************************************************************************/
87 /* SILC Client Operations. These must be implemented by the application. */
89 /* Message sent to the application by library. `conn' associates the
90 message to a specific connection. `conn', however, may be NULL. */
91 void (*say)(SilcClient client, SilcClientConnection conn, char *msg, ...);
93 /* Message for a channel. The `sender' is the sender of the message
94 The `channel' is the channel. */
95 void (*channel_message)(SilcClient client, SilcClientConnection conn,
96 SilcClientEntry sender, SilcChannelEntry channel,
99 /* Private message to the client. The `sender' is the sender of the
101 void (*private_message)(SilcClient client, SilcClientConnection conn,
102 SilcClientEntry sender, char *msg);
104 /* Notify message to the client. The notify arguments are sent in the
105 same order as servers sends them. The arguments are same as received
106 from the server except for ID's. If ID is received application receives
107 the corresponding entry to the ID. For example, if Client ID is received
108 application receives SilcClientEntry. Also, if the notify type is
109 for channel the channel entry is sent to application (even if server
110 does not send it because client library gets the channel entry from
111 the Channel ID in the packet's header). */
112 void (*notify)(SilcClient client, SilcClientConnection conn,
113 SilcNotifyType type, ...);
115 /* Command handler. This function is called always in the command function.
116 If error occurs it will be called as well. `conn' is the associated
117 client connection. `cmd_context' is the command context that was
118 originally sent to the command. `success' is FALSE if error occured
119 during command. `command' is the command being processed. It must be
120 noted that this is not reply from server. This is merely called just
121 after application has called the command. Just to tell application
122 that the command really was processed. */
123 void (*command)(SilcClient client, SilcClientConnection conn,
124 SilcClientCommandContext cmd_context, int success,
125 SilcCommand command);
127 /* Command reply handler. This function is called always in the command reply
128 function. If error occurs it will be called as well. Normal scenario
129 is that it will be called after the received command data has been parsed
130 and processed. The function is used to pass the received command data to
133 `conn' is the associated client connection. `cmd_payload' is the command
134 payload data received from server and it can be ignored. It is provided
135 if the application would like to re-parse the received command data,
136 however, it must be noted that the data is parsed already by the library
137 thus the payload can be ignored. `success' is FALSE if error occured.
138 In this case arguments are not sent to the application. The `status' is
139 the command reply status server returned. The `command' is the command
140 reply being processed. The function has variable argument list and each
141 command defines the number and type of arguments it passes to the
142 application (on error they are not sent). */
143 void (*command_reply)(SilcClient client, SilcClientConnection conn,
144 SilcCommandPayload cmd_payload, int success,
145 SilcCommand command, SilcCommandStatus status, ...);
147 /* Called to indicate that connection was either successfully established
148 or connecting failed. This is also the first time application receives
149 the SilcClientConnection objecet which it should save somewhere. */
150 void (*connect)(SilcClient client, SilcClientConnection conn, int success);
152 /* Called to indicate that connection was disconnected to the server. */
153 void (*disconnect)(SilcClient client, SilcClientConnection conn);
155 /* Find authentication method and authentication data by hostname and
156 port. The hostname may be IP address as well. The found authentication
157 method and authentication data is returned to `auth_meth', `auth_data'
158 and `auth_data_len'. The function returns TRUE if authentication method
159 is found and FALSE if not. `conn' may be NULL. */
160 int (*get_auth_method)(SilcClient client, SilcClientConnection conn,
161 char *hostname, unsigned short port,
162 SilcProtocolAuthMeth *auth_meth,
163 unsigned char **auth_data,
164 unsigned int *auth_data_len);
166 /* Verifies received public key. The `conn_type' indicates which entity
167 (server, client etc.) has sent the public key. If user decides to trust
168 the key may be saved as trusted public key for later use. If user does
169 not trust the key this returns FALSE. If everything is Ok this returns
171 int (*verify_public_key)(SilcClient client, SilcClientConnection conn,
172 SilcSocketType conn_type, unsigned char *pk,
173 unsigned int pk_len, SilcSKEPKType pk_type);
175 /* Ask (interact, that is) a passphrase from user. Returns the passphrase
177 unsigned char *(*ask_passphrase)(SilcClient client,
178 SilcClientConnection conn);
180 /* Notifies application that failure packet was received. This is called
181 if there is some protocol active in the client. The `protocol' is the
182 protocol context. The `failure' is opaque pointer to the failure
183 indication. Note, that the `failure' is protocol dependant and
184 application must explicitly cast it to correct type. Usually `failure'
185 is 32 bit failure type (see protocol specs for all protocol failure
187 void (*failure)(SilcClient client, SilcClientConnection conn,
188 SilcProtocol protocol, void *failure);
190 /* Asks whether the user would like to perform the key agreement protocol.
191 This is called after we have received an key agreement packet or an
192 reply to our key agreement packet. This returns TRUE if the user wants
193 the library to perform the key agreement protocol and FALSE if it is not
194 desired (application may start it later by calling the function
195 silc_client_perform_key_agreement). If TRUE is returned also the
196 `completion' and `context' arguments must be set by the application. */
197 int (*key_agreement)(SilcClient client, SilcClientConnection conn,
198 SilcClientEntry client_entry, char *hostname,
200 SilcKeyAgreementCallback *completion,
202 } SilcClientOperations;
206 /******************************************************************************
208 SILC Client Library API
210 This is the API that is published by the SILC Client Library for the
211 applications. These functions are implemented in the SILC Client Library.
212 Application may freely call these functions from the library.
214 ******************************************************************************/
216 /* Initialization functions (client.c) */
218 /* Allocates new client object. This has to be done before client may
219 work. After calling this one must call silc_client_init to initialize
220 the client. The `application' is application specific user data pointer
221 and caller must free it. */
222 SilcClient silc_client_alloc(SilcClientOperations *ops, void *application);
224 /* Frees client object and its internals. */
225 void silc_client_free(SilcClient client);
227 /* Initializes the client. This makes all the necessary steps to make
228 the client ready to be run. One must call silc_client_run to run the
229 client. Returns FALSE if error occured, TRUE otherwise. */
230 int silc_client_init(SilcClient client);
232 /* Runs the client. This starts the scheduler from the utility library.
233 When this functions returns the execution of the appliation is over. */
234 void silc_client_run(SilcClient client);
236 /* Stops the client. This is called to stop the client and thus to stop
238 void silc_client_stop(SilcClient client);
241 /* Connecting functions (client.c) */
243 /* Connects to remote server. This is the main routine used to connect
244 to SILC server. Returns -1 on error and the created socket otherwise.
245 The `context' is user context that is saved into the SilcClientConnection
246 that is created after the connection is created. Note that application
247 may handle the connecting process outside the library. If this is the
248 case then this function is not used at all. When the connecting is
249 done the `connect' client operation is called. */
250 int silc_client_connect_to_server(SilcClient client, int port,
251 char *host, void *context);
253 /* Allocates and adds new connection to the client. This adds the allocated
254 connection to the connection table and returns a pointer to it. A client
255 can have multiple connections to multiple servers. Every connection must
256 be added to the client using this function. User data `context' may
257 be sent as argument. This function is normally used only if the
258 application performed the connecting outside the library. The library
259 however may use this internally. */
260 SilcClientConnection silc_client_add_connection(SilcClient client,
265 /* Removes connection from client. Frees all memory. */
266 void silc_client_del_connection(SilcClient client, SilcClientConnection conn);
268 /* Adds listener socket to the listener sockets table. This function is
269 used to add socket objects that are listeners to the client. This should
270 not be used to add other connection objects. */
271 void silc_client_add_socket(SilcClient client, SilcSocketConnection sock);
273 /* Deletes listener socket from the listener sockets table. */
274 void silc_client_del_socket(SilcClient client, SilcSocketConnection sock);
276 /* Start SILC Key Exchange (SKE) protocol to negotiate shared secret
277 key material between client and server. This function can be called
278 directly if application is performing its own connecting and does not
279 use the connecting provided by this library. This function is normally
280 used only if the application performed the connecting outside the library.
281 The library however may use this internally. */
282 int silc_client_start_key_exchange(SilcClient client,
283 SilcClientConnection conn,
286 /* Closes connection to remote end. Free's all allocated data except
287 for some information such as nickname etc. that are valid at all time. */
288 void silc_client_close_connection(SilcClient client,
289 SilcClientConnection conn);
292 /* Message sending functions (client_channel.c and client_prvmsg.c) */
294 /* Sends packet to the `channel'. Packet to channel is always encrypted
295 differently from "normal" packets. SILC header of the packet is
296 encrypted with the next receiver's key and the rest of the packet is
297 encrypted with the channel specific key. Padding and HMAC is computed
298 with the next receiver's key. The `data' is the channel message. If
299 the `force_send' is TRUE then the packet is sent immediately.
301 If `key' is provided then that private key is used to encrypt the
302 channel message. If it is not provided, private keys has not been
303 set at all, the normal channel key is used automatically. If private
304 keys are set then the first key (the key that was added first as
305 private key) is used. */
306 void silc_client_send_channel_message(SilcClient client,
307 SilcClientConnection conn,
308 SilcChannelEntry channel,
309 SilcChannelPrivateKey key,
311 unsigned int data_len,
314 /* Sends private message to remote client. If private message key has
315 not been set with this client then the message will be encrypted using
316 normal session keys. Private messages are special packets in SILC
317 network hence we need this own function for them. This is similiar
318 to silc_client_packet_send_to_channel except that we send private
319 message. The `data' is the private message. If the `force_send' is
320 TRUE the packet is sent immediately. */
321 void silc_client_send_private_message(SilcClient client,
322 SilcClientConnection conn,
323 SilcClientEntry client_entry,
325 unsigned int data_len,
329 /* Client and Channel entry retrieval (idlist.c) */
331 /* Callback function given to the silc_client_get_client function. The
332 found entries are allocated into the `clients' array. The array must
333 not be freed by the caller, the library will free it later. If the
334 `clients' is NULL, no such clients exist in the SILC Network. */
335 typedef void (*SilcGetClientCallback)(SilcClient client,
336 SilcClientConnection conn,
337 SilcClientEntry *clients,
338 unsigned int clients_count,
341 /* Finds client entry or entries by the `nickname' and `server'. The
342 completion callback will be called when the client entries has been found.
344 Note: this function is always asynchronous and resolves the client
345 information from the server. Thus, if you already know the client
346 information then use the silc_client_get_client_by_id function to
347 get the client entry since this function may be very slow and should
348 be used only to initially get the client entries. */
349 void silc_client_get_clients(SilcClient client,
350 SilcClientConnection conn,
353 SilcGetClientCallback completion,
356 /* Same as above function but does not resolve anything from the server.
357 This checks local cache and returns all clients from the cache. */
358 SilcClientEntry *silc_client_get_clients_local(SilcClient client,
359 SilcClientConnection conn,
362 unsigned int *clients_count);
364 /* Gets client entries by the list of client ID's `client_id_list'. This
365 always resolves those client ID's it does not know yet from the server
366 so this function might take a while. The `client_id_list' is a list
367 of ID Payloads added one after other. JOIN command reply and USERS
368 command reply for example returns this sort of list. The `completion'
369 will be called after the entries are available. */
370 void silc_client_get_clients_by_list(SilcClient client,
371 SilcClientConnection conn,
372 unsigned int list_count,
373 SilcBuffer client_id_list,
374 SilcGetClientCallback completion,
377 /* Find entry for client by the client's ID. Returns the entry or NULL
378 if the entry was not found. */
379 SilcClientEntry silc_client_get_client_by_id(SilcClient client,
380 SilcClientConnection conn,
381 SilcClientID *client_id);
383 /* Same as above but will always resolve the information from the server.
384 Use this only if you know that you don't have the entry and the only
385 thing you know about the client is its ID. */
386 void silc_client_get_client_by_id_resolve(SilcClient client,
387 SilcClientConnection conn,
388 SilcClientID *client_id,
389 SilcGetClientCallback completion,
392 /* Finds entry for channel by the channel name. Returns the entry or NULL
393 if the entry was not found. It is found only if the client is joined
395 SilcChannelEntry silc_client_get_channel(SilcClient client,
396 SilcClientConnection conn,
400 /* Command management (command.c) */
402 /* Allocate Command Context. The context is defined in `command.h' file.
403 The context is used by the library commands and applications should use
404 it as well. However, application may choose to use some own context
405 for its local commands. All library commands, however, must use this
407 SilcClientCommandContext silc_client_command_alloc();
409 /* Free command context and its internals */
410 void silc_client_command_free(SilcClientCommandContext ctx);
412 /* Duplicate Command Context by adding reference counter. The context won't
413 be free'd untill it hits zero. */
414 SilcClientCommandContext silc_client_command_dup(SilcClientCommandContext ctx);
416 /* Finds and returns a pointer to the command list. Return NULL if the
417 command is not found. See the `command.[ch]' for the command list. */
418 SilcClientCommand *silc_client_command_find(const char *name);
420 /* Generic function to send any command. The arguments must be sent already
421 encoded into correct form and in correct order. */
422 void silc_client_send_command(SilcClient client, SilcClientConnection conn,
423 SilcCommand command, unsigned short ident,
424 unsigned int argc, ...);
426 /* Pending Command callback destructor. This is called after calling the
427 pending callback or if error occurs while processing the pending command.
428 If error occurs then the callback won't be called at all, and only this
429 destructor is called. The `context' is the context given for the function
430 silc_client_command_pending. */
431 typedef void (*SilcClientPendingDestructor)(void *context);
433 /* Add new pending command to be executed when reply to a command has been
434 received. The `reply_cmd' is the command that will call the `callback'
435 with `context' when reply has been received. If `ident is non-zero
436 the `callback' will be executed when received reply with command
437 identifier `ident'. */
438 void silc_client_command_pending(SilcClientConnection conn,
439 SilcCommand reply_cmd,
440 unsigned short ident,
441 SilcClientPendingDestructor destructor,
442 SilcCommandCb callback,
446 /* Private Message key management (client_prvmsg.c) */
448 /* Adds private message key to the client library. The key will be used to
449 encrypt all private message between the client and the remote client
450 indicated by the `client_entry'. If the `key' is NULL and the boolean
451 value `generate_key' is TRUE the library will generate random key.
452 The `key' maybe for example pre-shared-key, passphrase or similar.
453 The `cipher' MAY be provided but SHOULD be NULL to assure that the
454 requirements of the SILC protocol are met. The API, however, allows
455 to allocate any cipher.
457 It is not necessary to set key for normal private message usage. If the
458 key is not set then the private messages are encrypted using normal
459 session keys. Setting the private key, however, increases the security.
461 Returns FALSE if the key is already set for the `client_entry', TRUE
463 int silc_client_add_private_message_key(SilcClient client,
464 SilcClientConnection conn,
465 SilcClientEntry client_entry,
468 unsigned int key_len,
471 /* Same as above but takes the key material from the SKE key material
472 structure. This structure is received if the application uses the
473 silc_client_send_key_agreement to negotiate the key material. The
474 `cipher' SHOULD be provided as it is negotiated also in the SKE
476 int silc_client_add_private_message_key_ske(SilcClient client,
477 SilcClientConnection conn,
478 SilcClientEntry client_entry,
480 SilcSKEKeyMaterial *key);
482 /* Sends private message key payload to the remote client indicated by
483 the `client_entry'. If the `force_send' is TRUE the packet is sent
484 immediately. Returns FALSE if error occurs, TRUE otherwise. The
485 application should call this function after setting the key to the
488 Note that the key sent using this function is sent to the remote client
489 through the SILC network. The packet is protected using normal session
491 int silc_client_send_private_message_key(SilcClient client,
492 SilcClientConnection conn,
493 SilcClientEntry client_entry,
496 /* Removes the private message from the library. The key won't be used
497 after this to protect the private messages with the remote `client_entry'
498 client. Returns FALSE on error, TRUE otherwise. */
499 int silc_client_del_private_message_key(SilcClient client,
500 SilcClientConnection conn,
501 SilcClientEntry client_entry);
503 /* Returns array of set private message keys associated to the connection
504 `conn'. Returns allocated SilcPrivateMessageKeys array and the array
505 count to the `key_count' argument. The array must be freed by the caller
506 by calling the silc_client_free_private_message_keys function. Note:
507 the keys returned in the array is in raw format. It might not be desired
508 to show the keys as is. The application might choose not to show the keys
509 at all or to show the fingerprints of the keys. */
510 SilcPrivateMessageKeys
511 silc_client_list_private_message_keys(SilcClient client,
512 SilcClientConnection conn,
513 unsigned int *key_count);
515 /* Frees the SilcPrivateMessageKeys array returned by the function
516 silc_client_list_private_message_keys. */
517 void silc_client_free_private_message_keys(SilcPrivateMessageKeys keys,
518 unsigned int key_count);
521 /* Channel private key management (client_channel.c,
522 SilcChannelPrivateKey is defined in idlist.h) */
524 /* Adds private key for channel. This may be set only if the channel's mode
525 mask includes the SILC_CHANNEL_MODE_PRIVKEY. This returns FALSE if the
526 mode is not set. When channel has private key then the messages are
527 encrypted using that key. All clients on the channel must also know the
528 key in order to decrypt the messages. However, it is possible to have
529 several private keys per one channel. In this case only some of the
530 clients on the channel may know the one key and only some the other key.
532 The private key for channel is optional. If it is not set then the
533 channel messages are encrypted using the channel key generated by the
534 server. However, setting the private key (or keys) for the channel
535 significantly adds security. If more than one key is set the library
536 will automatically try all keys at the message decryption phase. Note:
537 setting many keys slows down the decryption phase as all keys has to
538 be tried in order to find the correct decryption key. However, setting
539 a few keys does not have big impact to the decryption performace.
541 NOTE: that this is entirely local setting. The key set using this function
542 is not sent to the network at any phase.
544 NOTE: If the key material was originated by the SKE protocol (using
545 silc_client_send_key_agreement) then the `key' MUST be the
546 key->send_enc_key as this is dictated by the SILC protocol. However,
547 currently it is not expected that the SKE key material would be used
548 as channel private key. However, this API allows it. */
549 int silc_client_add_channel_private_key(SilcClient client,
550 SilcClientConnection conn,
551 SilcChannelEntry channel,
555 unsigned int key_len);
557 /* Removes all private keys from the `channel'. The old channel key is used
558 after calling this to protect the channel messages. Returns FALSE on
559 on error, TRUE otherwise. */
560 int silc_client_del_channel_private_keys(SilcClient client,
561 SilcClientConnection conn,
562 SilcChannelEntry channel);
564 /* Removes and frees private key `key' from the channel `channel'. The `key'
565 is retrieved by calling the function silc_client_list_channel_private_keys.
566 The key is not used after this. If the key was last private key then the
567 old channel key is used hereafter to protect the channel messages. This
568 returns FALSE on error, TRUE otherwise. */
569 int silc_client_del_channel_private_key(SilcClient client,
570 SilcClientConnection conn,
571 SilcChannelEntry channel,
572 SilcChannelPrivateKey key);
574 /* Returns array (pointers) of private keys associated to the `channel'.
575 The caller must free the array by calling the function
576 silc_client_free_channel_private_keys. The pointers in the array may be
577 used to delete the specific key by giving the pointer as argument to the
578 function silc_client_del_channel_private_key. */
579 SilcChannelPrivateKey *
580 silc_client_list_channel_private_keys(SilcClient client,
581 SilcClientConnection conn,
582 SilcChannelEntry channel,
583 unsigned int *key_count);
585 /* Frees the SilcChannelPrivateKey array. */
586 void silc_client_free_channel_private_keys(SilcChannelPrivateKey *keys,
587 unsigned int key_count);
590 /* Key Agreement routines (client_keyagr.c) */
592 /* Sends key agreement request to the remote client indicated by the
593 `client_entry'. If the caller provides the `hostname' and the `port'
594 arguments then the library will bind the client to that hostname and
595 that port for the key agreement protocol. It also sends the `hostname'
596 and the `port' in the key agreement packet to the remote client. This
597 would indicate that the remote client may initiate the key agreement
598 protocol to the `hostname' on the `port'. If port is zero then the
599 bound port is undefined (the operating system defines it).
601 If the `hostname' and `port' is not provided then empty key agreement
602 packet is sent to the remote client. The remote client may reply with
603 the same packet including its hostname and port. If the library receives
604 the reply from the remote client the `key_agreement' client operation
605 callback will be called to verify whether the user wants to perform the
606 key agreement or not.
608 NOTE: If the application provided the `hostname' and the `port' and the
609 remote side initiates the key agreement protocol it is not verified
610 from the user anymore whether the protocol should be executed or not.
611 By setting the `hostname' and `port' the user gives permission to
612 perform the protocol (we are responder in this case).
614 NOTE: If the remote side decides not to initiate the key agreement
615 or decides not to reply with the key agreement packet then we cannot
616 perform the key agreement at all. If the key agreement protocol is
617 performed the `completion' callback with the `context' will be called.
618 If remote side decides to ignore the request the `completion' will be
619 called after the specified timeout, `timeout_secs'.
621 NOTE: There can be only one active key agreement for one client entry.
622 Before setting new one, the old one must be finished (it is finished
623 after calling the completion callback) or the function
624 silc_client_abort_key_agreement must be called. */
625 void silc_client_send_key_agreement(SilcClient client,
626 SilcClientConnection conn,
627 SilcClientEntry client_entry,
630 unsigned long timeout_secs,
631 SilcKeyAgreementCallback completion,
634 /* Performs the actual key agreement protocol. Application may use this
635 to initiate the key agreement protocol. This can be called for example
636 after the application has received the `key_agreement' client operation,
637 and did not return TRUE from it.
639 The `hostname' is the remote hostname (or IP address) and the `port'
640 is the remote port. The `completion' callback with the `context' will
641 be called after the key agreement protocol.
643 NOTE: If the application returns TRUE in the `key_agreement' client
644 operation the library will automatically start the key agreement. In this
645 case the application must not call this function. However, application
646 may choose to just ignore the `key_agreement' client operation (and
647 merely just print information about it on the screen) and call this
648 function when the user whishes to do so (by, for example, giving some
649 specific command). Thus, the API provides both, automatic and manual
650 initiation of the key agreement. Calling this function is the manual
651 initiation and returning TRUE in the `key_agreement' client operation
652 is the automatic initiation. */
653 void silc_client_perform_key_agreement(SilcClient client,
654 SilcClientConnection conn,
655 SilcClientEntry client_entry,
658 SilcKeyAgreementCallback completion,
661 /* Same as above but application has created already the connection to
662 the remote host. The `sock' is the socket to the remote connection.
663 Application can use this function if it does not want the client library
664 to create the connection. */
665 void silc_client_perform_key_agreement_fd(SilcClient client,
666 SilcClientConnection conn,
667 SilcClientEntry client_entry,
670 SilcKeyAgreementCallback completion,
673 /* This function can be called to unbind the hostname and the port for
674 the key agreement protocol. However, this function has effect only
675 before the key agreement protocol has been performed. After it has
676 been performed the library will automatically unbind the port. The
677 `client_entry' is the client to which we sent the key agreement
679 void silc_client_abort_key_agreement(SilcClient client,
680 SilcClientConnection conn,
681 SilcClientEntry client_entry);