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 /******************************************************************************
40 SILC Client Operations
42 These functions must be implemented by the application calling the SILC
43 client library. The client library can call these functions at any time.
45 To use this structure: define a static SilcClientOperations variable,
46 fill it and pass its pointer to silc_client_alloc function.
48 ******************************************************************************/
50 /* SILC Client Operations. These must be implemented by the application. */
52 /* Message sent to the application by library. `conn' associates the
53 message to a specific connection. `conn', however, may be NULL. */
54 void (*say)(SilcClient client, SilcClientConnection conn, char *msg, ...);
56 /* Message for a channel. The `sender' is the sender of the message
57 The `channel' is the channel. */
58 void (*channel_message)(SilcClient client, SilcClientConnection conn,
59 SilcClientEntry sender, SilcChannelEntry channel,
62 /* Private message to the client. The `sender' is the sender of the
64 void (*private_message)(SilcClient client, SilcClientConnection conn,
65 SilcClientEntry sender, char *msg);
68 /* Notify message to the client. The notify arguments are sent in the
69 same order as servers sends them. The arguments are same as received
70 from the server except for ID's. If ID is received application receives
71 the corresponding entry to the ID. For example, if Client ID is received
72 application receives SilcClientEntry. Also, if the notify type is
73 for channel the channel entry is sent to application (even if server
74 does not send it because client library gets the channel entry from
75 the Channel ID in the packet's header). */
76 void (*notify)(SilcClient client, SilcClientConnection conn,
77 SilcNotifyType type, ...);
80 /* Command handler. This function is called always in the command function.
81 If error occurs it will be called as well. `conn' is the associated
82 client connection. `cmd_context' is the command context that was
83 originally sent to the command. `success' is FALSE if error occured
84 during command. `command' is the command being processed. It must be
85 noted that this is not reply from server. This is merely called just
86 after application has called the command. Just to tell application
87 that the command really was processed. */
88 void (*command)(SilcClient client, SilcClientConnection conn,
89 SilcClientCommandContext cmd_context, int success,
93 /* Command reply handler. This function is called always in the command reply
94 function. If error occurs it will be called as well. Normal scenario
95 is that it will be called after the received command data has been parsed
96 and processed. The function is used to pass the received command data to
99 `conn' is the associated client connection. `cmd_payload' is the command
100 payload data received from server and it can be ignored. It is provided
101 if the application would like to re-parse the received command data,
102 however, it must be noted that the data is parsed already by the library
103 thus the payload can be ignored. `success' is FALSE if error occured.
104 In this case arguments are not sent to the application. The `status' is
105 the command reply status server returned. The `command' is the command
106 reply being processed. The function has variable argument list and each
107 command defines the number and type of arguments it passes to the
108 application (on error they are not sent). */
109 void (*command_reply)(SilcClient client, SilcClientConnection conn,
110 SilcCommandPayload cmd_payload, int success,
111 SilcCommand command, SilcCommandStatus status, ...);
113 /* Called to indicate that connection was either successfully established
114 or connecting failed. This is also the first time application receives
115 the SilcClientConnection objecet which it should save somewhere. */
116 void (*connect)(SilcClient client, SilcClientConnection conn, int success);
118 /* Called to indicate that connection was disconnected to the server. */
119 void (*disconnect)(SilcClient client, SilcClientConnection conn);
121 /* Find authentication method and authentication data by hostname and
122 port. The hostname may be IP address as well. The found authentication
123 method and authentication data is returned to `auth_meth', `auth_data'
124 and `auth_data_len'. The function returns TRUE if authentication method
125 is found and FALSE if not. `conn' may be NULL. */
126 int (*get_auth_method)(SilcClient client, SilcClientConnection conn,
127 char *hostname, unsigned short port,
128 SilcProtocolAuthMeth *auth_meth,
129 unsigned char **auth_data,
130 unsigned int *auth_data_len);
132 /* Verifies received public key. The public key has been received from
133 a server. If user decides to trust the key may be saved as trusted
134 server key for later use. If user does not trust the key this returns
135 FALSE. If everything is Ok this returns TRUE. */
136 int (*verify_server_key)(SilcClient client, SilcClientConnection conn,
137 unsigned char *pk, unsigned int pk_len,
138 SilcSKEPKType pk_type);
140 /* Ask (interact, that is) a passphrase from user. Returns the passphrase
142 unsigned char *(*ask_passphrase)(SilcClient client,
143 SilcClientConnection conn);
145 /* Notifies application that failure packet was received. This is called
146 if there is some protocol active in the client. The `protocol' is the
147 protocol context. The `failure' is opaque pointer to the failure
148 indication. Note, that the `failure' is protocol dependant and
149 application must explicitly cast it to correct type. Usually `failure'
150 is 32 bit failure type (see protocol specs for all protocol failure
152 void (*failure)(SilcClient client, SilcClientConnection conn,
153 SilcProtocol protocol, void *failure);
154 } SilcClientOperations;
158 /******************************************************************************
160 SILC Client Library API
162 This is the API that is published by the SILC Client Library for the
163 applications. These functions are implemented in the SILC Client Library.
164 Application may freely call these functions from the library.
166 ******************************************************************************/
168 /* Initialization functions */
170 /* Allocates new client object. This has to be done before client may
171 work. After calling this one must call silc_client_init to initialize
172 the client. The `application' is application specific user data pointer
173 and caller must free it. */
174 SilcClient silc_client_alloc(SilcClientOperations *ops, void *application);
176 /* Frees client object and its internals. */
177 void silc_client_free(SilcClient client);
179 /* Initializes the client. This makes all the necessary steps to make
180 the client ready to be run. One must call silc_client_run to run the
181 client. Returns FALSE if error occured, TRUE otherwise. */
182 int silc_client_init(SilcClient client);
184 /* Runs the client. This starts the scheduler from the utility library.
185 When this functions returns the execution of the appliation is over. */
186 void silc_client_run(SilcClient client);
188 /* Stops the client. This is called to stop the client and thus to stop
190 void silc_client_stop(SilcClient client);
193 /* Connecting functions */
195 /* Connects to remote server. This is the main routine used to connect
196 to SILC server. Returns -1 on error and the created socket otherwise.
197 The `context' is user context that is saved into the SilcClientConnection
198 that is created after the connection is created. Note that application
199 may handle the connecting process outside the library. If this is the
200 case then this function is not used at all. When the connecting is
201 done the `connect' client operation is called. */
202 int silc_client_connect_to_server(SilcClient client, int port,
203 char *host, void *context);
205 /* Allocates and adds new connection to the client. This adds the allocated
206 connection to the connection table and returns a pointer to it. A client
207 can have multiple connections to multiple servers. Every connection must
208 be added to the client using this function. User data `context' may
209 be sent as argument. This function is normally used only if the
210 application performed the connecting outside the library. The library
211 however may use this internally. */
212 SilcClientConnection silc_client_add_connection(SilcClient client,
217 /* Removes connection from client. Frees all memory. */
218 void silc_client_del_connection(SilcClient client, SilcClientConnection conn);
220 /* Start SILC Key Exchange (SKE) protocol to negotiate shared secret
221 key material between client and server. This function can be called
222 directly if application is performing its own connecting and does not
223 use the connecting provided by this library. This function is normally
224 used only if the application performed the connecting outside the library.
225 The library however may use this internally. */
226 int silc_client_start_key_exchange(SilcClient client,
227 SilcClientConnection conn,
230 /* Closes connection to remote end. Free's all allocated data except
231 for some information such as nickname etc. that are valid at all time. */
232 void silc_client_close_connection(SilcClient client,
233 SilcClientConnection conn);
236 /* Packet sending functions */
238 /* Sends packet to the `channel'. Packet to channel is always encrypted
239 differently from "normal" packets. SILC header of the packet is
240 encrypted with the next receiver's key and the rest of the packet is
241 encrypted with the channel specific key. Padding and HMAC is computed
242 with the next receiver's key. The `data' is the channel message. If
243 the `force_send' is TRUE then the packet is sent immediately. */
244 void silc_client_send_channel_message(SilcClient client,
245 SilcClientConnection conn,
246 SilcChannelEntry channel,
248 unsigned int data_len,
251 /* Sends private message to remote client. If private message key has
252 not been set with this client then the message will be encrypted using
253 normal session keys. Private messages are special packets in SILC
254 network hence we need this own function for them. This is similiar
255 to silc_client_packet_send_to_channel except that we send private
256 message. The `data' is the private message. If the `force_send' is
257 TRUE the packet is sent immediately. */
258 void silc_client_send_private_message(SilcClient client,
259 SilcClientConnection conn,
260 SilcClientEntry client_entry,
262 unsigned int data_len,
266 /* Private Message key management */
268 /* Adds private message key to the client library. The key will be used to
269 encrypt all private message between the client and the remote client
270 indicated by the `client_entry'. If `key' is NULL and the boolean value
271 `generate_key' is TRUE then the library will generate random key.
272 Otherwise the `key' provided by the application will be used. It maybe
273 random key or pre-shared-key.
275 It is not necessary to set key for normal private message usage. If the
276 key is not set then the private messages are encrypted using normal
277 session keys. Setting the private key, however, increases the security.
279 Note that the key set using this function is sent to the remote client
280 through the SILC network. The packet is protected using normal session
283 Returns FALSE if the key is already set for the `client_entry', TRUE
285 int silc_client_add_private_message_key(SilcClient client,
286 SilcClientConnection conn,
287 SilcClientConnection client_entry,
289 unsigned int key_len,
292 /* Removes the private message from the library. The key won't be used
293 after this to protect the private messages with the remote `client_entry'
294 client. Returns FALSE on error, TRUE otherwise. */
295 int silc_client_del_private_message_key(SilcClient client,
296 SilcClientConnection conn,
297 SilcClientEntry client_entry);
299 /* Structure to hold the list of private message keys. The array of this
300 structure is returned by the silc_client_list_private_message_keys
303 SilcClientEntry client_entry; /* The remote client entry */
304 unsigned char *key; /* The raw key data */
305 unsigned int key_len; /* The key length */
306 int generated; /* TRUE if library generated the key */
307 } *SilcPrivateMessageKeys;
309 /* Returns array of set private message keys associated to the connection
310 `conn'. Returns allocated SilcPrivateMessageKeys array and the array
311 count to the `key_count' argument. The array must be freed by the caller
312 by calling the silc_client_free_private_message_keys function. Note:
313 the keys returned in the array is in raw format. It might not be desired
314 to show the keys as is. The application might choose not to show the keys
315 at all or to show the fingerprints of the keys. */
316 SilcPrivateMessageKeys
317 silc_client_list_private_message_keys(SilcClient client,
318 SilcClientConnection conn,
319 unsigned int *key_count);
321 /* Frees the SilcPrivateMessageKeys array returned by the function
322 silc_client_list_private_message_keys. */
323 void silc_client_free_private_message_keys(SilcPrivateMessageKeys keys,
324 unsigned int key_count);
327 /* Channel Message (private) key management */
329 /* Adds private key for channel. This may be set only if the channel's mode
330 mask includes the SILC_CHANNEL_MODE_PRIVKEY. This returns FALSE if the
331 mode is not set. When channel has private key then the messages are
332 encrypted using that key. All clients on the channel must also know the
333 key in order to decrypt the messages. However, it is possible to have
334 several private keys per one channel. In this case only some of the
335 clients on the channel may now the one key and only some the other key.
337 The private key for channel is optional. If it is not set then the
338 channel messages are encrypted using the channel key generated by the
339 server. However, setting the private key (or keys) for the channel
340 significantly adds security. If more than one key is set the library
341 will automatically try all keys at the message decryption phase. Note:
342 setting many keys slows down the decryption phase as all keys has to
343 be tried in order to find the correct decryption key. However, setting
344 a few keys does not have big impact to the decryption performace.
346 Note that this is entirely local setting. The key set using this function
347 is not sent to the network at any phase. */
348 int silc_client_add_channel_private_key(SilcClient client,
349 SilcClientConnection conn,
350 SilcChannelEntry channel,
352 unsigned int key_len);
354 /* Removes all private keys from the `channel'. The old channel key is used
355 after calling this to protect the channel messages. Returns FALSE on
356 on error, TRUE otherwise. */
357 int silc_client_del_channel_private_keys(SilcClient client,
358 SilcClientConnection conn,
359 SilcChannelEntry channel);
361 /* Structure to hold one channel private key. */
363 unsigned char *key; /* The key */
364 unsigned int key_len; /* The key length */
365 } *SilcChannelPrivateKey;
367 /* Removes and frees private key `key' from the channel `channel'. The `key'
368 is retrieved by calling the function silc_client_list_channel_private_keys.
369 The key is not used after this. If the key was last private key then the
370 old channel key is used hereafter to protect the channel messages. This
371 returns FALSE on error, TRUE otherwise. */
372 int silc_client_del_channel_private_key(SilcClient client,
373 SilcClientConnection conn,
374 SilcChannelEntry channel,
375 SilcChannelPrivateKey key);
377 /* Returns array (pointers) of private keys associated to the `channel'.
378 The caller must free the array by calling the function
379 silc_client_free_channel_private_keys. The pointers in the array may be
380 used to delete the specific key by giving the pointer as argument to the
381 function silc_client_del_channel_private_key. */
382 SilcChannelPrivateKey *
383 silc_client_list_channel_private_keys(SilcClient client,
384 SilcClientConnection conn,
385 SilcChannelEntry channel,
386 unsigned int key_count);
388 /* Frees the SilcChannelPrivateKey array. */
389 void silc_client_free_channel_private_keys(SilcChannelPrivateKey *keys,
390 unsigned int key_count);
393 /* Client and Channel entry retrieval */
395 /* Callback function given to the silc_client_get_client function. The
396 found entries are allocated into the `clients' array. The array must
397 not be freed by the caller, the library will free it later. If the
398 `clients' is NULL, no such clients exist in the SILC Network. */
399 typedef void (*SilcGetClientCallback)(SilcClient client,
400 SilcClientConnection conn,
401 SilcClientEntry *clients,
402 unsigned int clients_count,
405 /* Finds client entry or entries by the `nickname' and `server'. The
406 completion callback will be called when the client entries has been found.
408 Note: this function is always asynchronous and resolves the client
409 information from the server. Thus, if you already know the client
410 information then use the silc_client_get_client_by_id function to
411 get the client entry since this function may be very slow and should
412 be used only to initially get the client entries. */
413 void silc_client_get_clients(SilcClient client,
414 SilcClientConnection conn,
417 SilcGetClientCallback completion,
420 /* Same as above function but does not resolve anything from the server.
421 This checks local cache and returns all clients from the cache. */
422 SilcClientEntry *silc_client_get_clients_local(SilcClient client,
423 SilcClientConnection conn,
426 unsigned int *clients_count);
428 /* Find entry for client by the client's ID. Returns the entry or NULL
429 if the entry was not found. */
430 SilcClientEntry silc_client_get_client_by_id(SilcClient client,
431 SilcClientConnection conn,
432 SilcClientID *client_id);
434 /* Finds entry for channel by the channel name. Returns the entry or NULL
435 if the entry was not found. It is found only if the client is joined
437 SilcChannelEntry silc_client_get_channel(SilcClient client,
438 SilcClientConnection conn,