lib/silcclient/client_register.c

   1 /*
   2
   3   client_register.c
   4
   5   Author: Pekka Riikonen <priikone@silcnet.org>
   6
   7   Copyright (C) 2006 - 2007 Pekka Riikonen
   8
   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.
  12
  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.
  17
  18 */
  19
  20 #include "silc.h"
  21 #include "silcclient.h"
  22 #include "client_internal.h"
  23
  24 /************************** Types and definitions ***************************/
  25
  26 /* Resume session context */
  27 typedef struct {
  28   SilcClient client;
  29   SilcClientConnection conn;
  30   SilcBufferStruct detach;
  31   char *nickname;
  32   SilcUInt32 channel_count;
  33 } *SilcClientResumeSession;
  34
  35 /************************ Static utility functions **************************/
  36
  37 /* Command callback.  Nothing interesting to do here. */
  38
  39 static SilcBool
  40 silc_client_register_command_called(SilcClient client,
  41                                     SilcClientConnection conn,
  42                                     SilcCommand command,
  43                                     SilcStatus status,
  44                                     SilcStatus error,
  45                                     void *context,
  46                                     va_list ap)
  47 {
  48   return FALSE;
  49 }
  50
  51 /* Continues resuming after resolving.  Continue after last reply. */
  52
  53 static SilcBool
  54 silc_client_resume_continue(SilcClient client,
  55                             SilcClientConnection conn,
  56                             SilcCommand command,
  57                             SilcStatus status,
  58                             SilcStatus error,
  59                             void *context,
  60                             va_list ap)
  61 {
  62   if (status == SILC_STATUS_OK || status == SILC_STATUS_LIST_END ||
  63       SILC_STATUS_IS_ERROR(status)) {
  64     silc_fsm_continue(&conn->internal->event_thread);
  65     return FALSE;
  66   }
  67
  68   return TRUE;
  69 }
  70
  71 /* Function used to call command replies back to application in resuming. */
  72
  73 static void
  74 silc_client_resume_command_callback(SilcClient client,
  75                                     SilcClientConnection conn,
  76                                     SilcCommand command, ...)
  77 {
  78   va_list ap;
  79   va_start(ap, command);
  80   client->internal->ops->command_reply(client, conn, command,
  81                                        SILC_STATUS_OK, SILC_STATUS_OK, ap);
  82   va_end(ap);
  83 }
  84
  85
  86 /****************************** NEW_ID packet *******************************/
  87
  88 /* Received new ID packet from server during registering to SILC network */
  89
  90 SILC_FSM_STATE(silc_client_new_id)
  91 {
  92   SilcClientConnection conn = fsm_context;
  93   SilcClient client = conn->client;
  94   SilcPacket packet = state_context;
  95   SilcID id;
  96
  97   if (conn->local_id)
  98     goto out;
  99
 100   SILC_LOG_DEBUG(("New ID received from server"));
 101
 102   if (!silc_id_payload_parse_id(silc_buffer_data(&packet->buffer),
 103                                 silc_buffer_len(&packet->buffer), &id))
 104     goto out;
 105
 106   SILC_LOG_DEBUG(("New ID %s", silc_id_render(&id.u.client_id,
 107                                               SILC_ID_CLIENT)));
 108
 109   /* Create local client entry */
 110   conn->local_entry = silc_client_add_client(client, conn,
 111                                              client->username,
 112                                              client->username,
 113                                              client->realname,
 114                                              &id.u.client_id, 0);
 115   if (!conn->local_entry)
 116     goto out;
 117
 118   /* Save the ID.  Take reference to conn->local_id. */
 119   conn->local_id = &conn->local_entry->id;
 120   conn->internal->local_idp = silc_buffer_copy(&packet->buffer);
 121
 122   /* Save remote ID */
 123   if (packet->src_id_len) {
 124     conn->internal->remote_idp =
 125       silc_id_payload_encode_data(packet->src_id,
 126                                   packet->src_id_len,
 127                                   packet->src_id_type);
 128     if (!conn->internal->remote_idp)
 129       goto out;
 130     silc_id_payload_parse_id(silc_buffer_data(conn->internal->remote_idp),
 131                              silc_buffer_len(conn->internal->remote_idp),
 132                              &conn->remote_id);
 133   }
 134
 135   /* Set IDs to the packet stream */
 136   silc_packet_set_ids(conn->stream, SILC_ID_CLIENT, conn->local_id,
 137                       conn->remote_id.type, SILC_ID_GET_ID(conn->remote_id));
 138
 139   /* Signal connection that new ID was received so it can continue
 140      with the registering. */
 141   if (conn->internal->registering)
 142     silc_fsm_continue_sync(&conn->internal->event_thread);
 143
 144  out:
 145   /** Packet processed */
 146   silc_packet_free(packet);
 147   return SILC_FSM_FINISH;
 148 }
 149
 150
 151 /************************ Register to SILC network **************************/
 152
 153 /* Register to network */
 154
 155 SILC_FSM_STATE(silc_client_st_register)
 156 {
 157   SilcClientConnection conn = fsm_context;
 158   SilcClient client = conn->client;
 159
 160   SILC_LOG_DEBUG(("Register to network"));
 161
 162   /* Send NEW_CLIENT packet to register to network */
 163   if (!silc_packet_send_va(conn->stream, SILC_PACKET_NEW_CLIENT, 0,
 164                            SILC_STR_UI_SHORT(strlen(client->username)),
 165                            SILC_STR_DATA(client->username,
 166                                          strlen(client->username)),
 167                            SILC_STR_UI_SHORT(strlen(client->realname)),
 168                            SILC_STR_DATA(client->realname,
 169                                          strlen(client->realname)),
 170                            SILC_STR_END)) {
 171     /** Error sending packet */
 172     silc_fsm_next(fsm, silc_client_st_register_error);
 173     return SILC_FSM_CONTINUE;
 174   }
 175
 176   /** Wait for new ID */
 177   conn->internal->registering = TRUE;
 178   silc_fsm_next_later(fsm, silc_client_st_register_complete,
 179                       conn->internal->retry_timer, 0);
 180   return SILC_FSM_WAIT;
 181 }
 182
 183 /* Wait for NEW_ID packet to arrive */
 184
 185 SILC_FSM_STATE(silc_client_st_register_complete)
 186 {
 187   SilcClientConnection conn = fsm_context;
 188   SilcClient client = conn->client;
 189
 190   if (conn->internal->disconnected) {
 191     /** Disconnected */
 192     silc_fsm_next(fsm, silc_client_st_register_error);
 193     return SILC_FSM_CONTINUE;
 194   }
 195
 196   if (!conn->local_id) {
 197     if (conn->internal->retry_count++ >= SILC_CLIENT_RETRY_COUNT) {
 198       /** Timeout, ID not received */
 199       conn->internal->registering = FALSE;
 200       conn->internal->retry_count = 0;
 201       conn->internal->retry_timer = SILC_CLIENT_RETRY_MIN;
 202       silc_fsm_next(fsm, silc_client_st_register_error);
 203       return SILC_FSM_CONTINUE;
 204     }
 205
 206     /** Resend registering packet */
 207     silc_fsm_next(fsm, silc_client_st_register);
 208     conn->internal->retry_timer = ((conn->internal->retry_timer *
 209                                     SILC_CLIENT_RETRY_MUL) +
 210                                    (silc_rng_get_rn16(client->rng) %
 211                                     SILC_CLIENT_RETRY_RAND));
 212     return SILC_FSM_CONTINUE;
 213   }
 214
 215   SILC_LOG_DEBUG(("Registered to network"));
 216
 217   /* Issue IDENTIFY command for itself to get resolved hostname
 218      correctly from server. */
 219   silc_client_command_send(client, conn, SILC_COMMAND_IDENTIFY,
 220                            silc_client_register_command_called, NULL,
 221                            1, 5, silc_buffer_data(conn->internal->local_idp),
 222                            silc_buffer_len(conn->internal->local_idp));
 223
 224   /* Call NICK command if the nickname was set by the application (and is
 225      not same as the username). */
 226   if (conn->internal->params.nickname &&
 227       !silc_utf8_strcasecmp(conn->internal->params.nickname, client->username))
 228     silc_client_command_call(client, conn, NULL,
 229                              "NICK", conn->internal->params.nickname, NULL);
 230
 231   /* Issue INFO command to fetch the real server name and server
 232      information and other stuff. */
 233   silc_client_command_send(client, conn, SILC_COMMAND_INFO,
 234                            silc_client_register_command_called, NULL,
 235                            1, 2, silc_buffer_data(conn->internal->remote_idp),
 236                            silc_buffer_len(conn->internal->remote_idp));
 237
 238   /* Call connection callback.  We are now inside SILC network. */
 239   conn->callback(client, conn, SILC_CLIENT_CONN_SUCCESS, 0, NULL,
 240                  conn->callback_context);
 241
 242   conn->internal->registering = FALSE;
 243   silc_schedule_task_del_by_all(conn->internal->schedule, 0,
 244                                 silc_client_connect_timeout, conn);
 245
 246   return SILC_FSM_FINISH;
 247 }
 248
 249 /* Error registering to network */
 250
 251 SILC_FSM_STATE(silc_client_st_register_error)
 252 {
 253   SilcClientConnection conn = fsm_context;
 254
 255   SILC_LOG_DEBUG(("Error registering to network"));
 256
 257   /* Signal to close connection */
 258   conn->internal->status = SILC_CLIENT_CONN_ERROR;
 259   if (!conn->internal->disconnected) {
 260     conn->internal->disconnected = TRUE;
 261     SILC_FSM_EVENT_SIGNAL(&conn->internal->wait_event);
 262   }
 263
 264   silc_schedule_task_del_by_all(conn->internal->schedule, 0,
 265                                 silc_client_connect_timeout, conn);
 266
 267   return SILC_FSM_FINISH;
 268 }
 269
 270 /************************* Resume detached session **************************/
 271
 272 /* Resume detached session */
 273
 274 SILC_FSM_STATE(silc_client_st_resume)
 275 {
 276   SilcClientConnection conn = fsm_context;
 277   SilcClient client = conn->client;
 278   SilcClientResumeSession resume;
 279   SilcBuffer auth;
 280   unsigned char *id;
 281   SilcUInt16 id_len;
 282   SilcClientID client_id;
 283   int ret;
 284
 285   SILC_LOG_DEBUG(("Resuming detached session"));
 286
 287   resume = silc_calloc(1, sizeof(*resume));
 288   if (!resume) {
 289     /** Out of memory */
 290     silc_fsm_next(fsm, silc_client_st_resume_error);
 291     return SILC_FSM_CONTINUE;
 292   }
 293   silc_fsm_set_state_context(fsm, resume);
 294
 295   silc_buffer_set(&resume->detach, conn->internal->params.detach_data,
 296                   conn->internal->params.detach_data_len);
 297   SILC_LOG_HEXDUMP(("Detach data"), silc_buffer_data(&resume->detach),
 298                    silc_buffer_len(&resume->detach));
 299
 300   /* Take the old client ID from the detachment data */
 301   ret = silc_buffer_unformat(&resume->detach,
 302                              SILC_STR_ADVANCE,
 303                              SILC_STR_UI16_NSTRING_ALLOC(&resume->nickname,
 304                                                          NULL),
 305                              SILC_STR_UI16_NSTRING(&id, &id_len),
 306                              SILC_STR_UI_INT(NULL),
 307                              SILC_STR_UI_INT(&resume->channel_count),
 308                              SILC_STR_END);
 309   if (ret < 0) {
 310     /** Malformed detach data */
 311     SILC_LOG_DEBUG(("Malformed detachment data"));
 312     silc_fsm_next(fsm, silc_client_st_resume_error);
 313     return SILC_FSM_CONTINUE;
 314   }
 315
 316   if (!silc_id_str2id(id, id_len, SILC_ID_CLIENT, &client_id,
 317                       sizeof(client_id))) {
 318     /** Malformed ID */
 319     SILC_LOG_DEBUG(("Malformed ID"));
 320     silc_fsm_next(fsm, silc_client_st_resume_error);
 321     return SILC_FSM_CONTINUE;
 322   }
 323
 324   /* Generate authentication data that server will verify */
 325   auth = silc_auth_public_key_auth_generate(conn->public_key,
 326                                             conn->private_key,
 327                                             client->rng,
 328                                             conn->internal->hash,
 329                                             &client_id, SILC_ID_CLIENT);
 330   if (!auth) {
 331     /** Out of memory */
 332     silc_fsm_next(fsm, silc_client_st_resume_error);
 333     return SILC_FSM_CONTINUE;
 334   }
 335
 336   /* Send RESUME_CLIENT packet to resume to network */
 337   if (!silc_packet_send_va(conn->stream, SILC_PACKET_RESUME_CLIENT, 0,
 338                            SILC_STR_UI_SHORT(id_len),
 339                            SILC_STR_DATA(id, id_len),
 340                            SILC_STR_DATA(silc_buffer_data(auth),
 341                                          silc_buffer_len(auth)),
 342                            SILC_STR_END)) {
 343     /** Error sending packet */
 344     SILC_LOG_DEBUG(("Error sending packet"));
 345     silc_fsm_next(fsm, silc_client_st_resume_error);
 346     return SILC_FSM_CONTINUE;
 347   }
 348
 349   /** Wait for new ID */
 350   conn->internal->registering = TRUE;
 351   silc_fsm_next_later(fsm, silc_client_st_resume_resolve_channels, 15, 0);
 352   return SILC_FSM_WAIT;
 353 }
 354
 355 /* Resolve the old session information, user mode and joined channels. */
 356
 357 SILC_FSM_STATE(silc_client_st_resume_resolve_channels)
 358 {
 359   SilcClientConnection conn = fsm_context;
 360   SilcClient client = conn->client;
 361   SilcClientResumeSession resume = state_context;
 362   SilcUInt32 *res_argv_lens = NULL, *res_argv_types = NULL, res_argc = 0;
 363   unsigned char **res_argv = NULL;
 364   int i;
 365
 366   if (conn->internal->disconnected) {
 367     /** Disconnected */
 368     silc_fsm_next(fsm, silc_client_st_resume_error);
 369     return SILC_FSM_CONTINUE;
 370   }
 371
 372   if (!conn->local_id) {
 373     /** Timeout, ID not received */
 374     conn->internal->registering = FALSE;
 375     silc_fsm_next(fsm, silc_client_st_resume_error);
 376     return SILC_FSM_CONTINUE;
 377   }
 378
 379   /** Wait for channels */
 380   silc_fsm_next(fsm, silc_client_st_resume_resolve_cmodes);
 381
 382   /* Change our nickname */
 383   silc_client_change_nickname(client, conn, conn->local_entry,
 384                               resume->nickname, NULL, NULL, 0);
 385
 386   /* Send UMODE command to get our own user mode in the network */
 387   SILC_LOG_DEBUG(("Resolving user mode"));
 388   silc_client_command_send(client, conn, SILC_COMMAND_UMODE,
 389                            silc_client_register_command_called, NULL,
 390                            1, 1, silc_buffer_data(conn->internal->local_idp),
 391                            silc_buffer_len(conn->internal->local_idp));
 392
 393   if (!resume->channel_count)
 394     return SILC_FSM_YIELD;
 395
 396   /* Send IDENTIFY command for all channels we know about.  These are the
 397      channels we've joined to according our detachment data. */
 398   for (i = 0; i < resume->channel_count; i++) {
 399     SilcChannelEntry channel;
 400     unsigned char *chid;
 401     SilcUInt16 chid_len;
 402     SilcBuffer idp;
 403     SilcChannelID channel_id;
 404     char *name;
 405
 406     if (silc_buffer_unformat(&resume->detach,
 407                              SILC_STR_ADVANCE,
 408                              SILC_STR_UI16_NSTRING(&name, NULL),
 409                              SILC_STR_UI16_NSTRING(&chid, &chid_len),
 410                              SILC_STR_UI_INT(NULL),
 411                              SILC_STR_END) < 0)
 412       continue;
 413
 414     if (!silc_id_str2id(chid, chid_len, SILC_ID_CHANNEL, &channel_id,
 415                         sizeof(channel_id)))
 416       continue;
 417     idp = silc_id_payload_encode_data(chid, chid_len, SILC_ID_CHANNEL);
 418     if (!idp)
 419       continue;
 420
 421     /* Add the channel to cache */
 422     channel = silc_client_get_channel_by_id(client, conn, &channel_id);
 423     if (!channel)
 424       silc_client_add_channel(client, conn, name, 0, &channel_id);
 425
 426     res_argv = silc_realloc(res_argv, sizeof(*res_argv) * (res_argc + 1));
 427     res_argv_lens = silc_realloc(res_argv_lens, sizeof(*res_argv_lens) *
 428                                  (res_argc + 1));
 429     res_argv_types = silc_realloc(res_argv_types, sizeof(*res_argv_types) *
 430                                   (res_argc + 1));
 431     res_argv[res_argc] = silc_buffer_steal(idp, &res_argv_lens[res_argc]);
 432     res_argv_types[res_argc] = res_argc + 5;
 433     res_argc++;
 434     silc_buffer_free(idp);
 435   }
 436
 437   /* Send IDENTIFY command */
 438   SILC_LOG_DEBUG(("Resolving joined channels"));
 439   silc_client_command_send_argv(client, conn, SILC_COMMAND_IDENTIFY,
 440                                 silc_client_resume_continue, conn,
 441                                 res_argc, res_argv, res_argv_lens,
 442                                 res_argv_types);
 443
 444   for (i = 0; i < resume->channel_count; i++)
 445     silc_free(res_argv[i]);
 446   silc_free(res_argv);
 447   silc_free(res_argv_lens);
 448   silc_free(res_argv_types);
 449
 450   return SILC_FSM_WAIT;
 451 }
 452
 453 /* Resolve joined channel modes, users and topics. */
 454
 455 SILC_FSM_STATE(silc_client_st_resume_resolve_cmodes)
 456 {
 457   SilcClientConnection conn = fsm_context;
 458   SilcClient client = conn->client;
 459   SilcClientResumeSession resume = state_context;
 460   SilcIDCacheEntry entry;
 461   SilcChannelEntry channel;
 462   SilcList channels;
 463   SilcBuffer idp;
 464
 465   if (conn->internal->disconnected) {
 466     /** Disconnected */
 467     silc_fsm_next(fsm, silc_client_st_resume_error);
 468     return SILC_FSM_CONTINUE;
 469   }
 470
 471   SILC_LOG_DEBUG(("Resolving channel details"));
 472
 473   /** Wait for channel modes */
 474   silc_fsm_next(fsm, silc_client_st_resume_completed);
 475
 476   if (!silc_idcache_get_all(conn->internal->channel_cache, &channels))
 477     return SILC_FSM_YIELD;
 478
 479   /* Resolve channels' mode, users and topic */
 480   resume->channel_count = silc_list_count(channels) * 3;
 481   silc_list_start(channels);
 482   while ((entry = silc_list_get(channels))) {
 483     channel = entry->context;
 484     idp = silc_id_payload_encode(&channel->id, SILC_ID_CHANNEL);
 485     if (!idp)
 486       continue;
 487
 488     silc_client_command_send(client, conn, SILC_COMMAND_CMODE,
 489                              silc_client_resume_continue, conn, 1,
 490                              1, silc_buffer_data(idp),
 491                              silc_buffer_len(idp));
 492     silc_client_command_send(client, conn, SILC_COMMAND_USERS,
 493                              silc_client_resume_continue, conn, 1,
 494                              1, silc_buffer_data(idp),
 495                              silc_buffer_len(idp));
 496     silc_client_command_send(client, conn, SILC_COMMAND_TOPIC,
 497                              silc_client_resume_continue, conn, 1,
 498                              1, silc_buffer_data(idp),
 499                              silc_buffer_len(idp));
 500     silc_buffer_free(idp);
 501   }
 502
 503   return SILC_FSM_WAIT;
 504 }
 505
 506 /* Resuming completed */
 507
 508 SILC_FSM_STATE(silc_client_st_resume_completed)
 509 {
 510   SilcClientConnection conn = fsm_context;
 511   SilcClient client = conn->client;
 512   SilcClientResumeSession resume = state_context;
 513   SilcIDCacheEntry entry;
 514   SilcChannelEntry channel;
 515   SilcList channels;
 516
 517   if (conn->internal->disconnected) {
 518     /** Disconnected */
 519     silc_fsm_next(fsm, silc_client_st_resume_error);
 520     return SILC_FSM_CONTINUE;
 521   }
 522
 523   if (resume->channel_count > 0) {
 524     resume->channel_count--;
 525     if (resume->channel_count)
 526       return SILC_FSM_WAIT;
 527   }
 528
 529   SILC_LOG_DEBUG(("Resuming completed"));
 530
 531   /* Issue IDENTIFY command for itself to get resolved hostname
 532      correctly from server. */
 533   silc_client_command_send(client, conn, SILC_COMMAND_IDENTIFY,
 534                            silc_client_register_command_called, NULL,
 535                            1, 5, silc_buffer_data(conn->internal->local_idp),
 536                            silc_buffer_len(conn->internal->local_idp));
 537
 538   /* Issue INFO command to fetch the real server name and server
 539      information and other stuff. */
 540   silc_client_command_send(client, conn, SILC_COMMAND_INFO,
 541                            silc_client_register_command_called, NULL,
 542                            1, 2, silc_buffer_data(conn->internal->remote_idp),
 543                            silc_buffer_len(conn->internal->remote_idp));
 544
 545   /* Call connection callback.  We have now resumed to SILC network. */
 546   conn->callback(client, conn, SILC_CLIENT_CONN_SUCCESS_RESUME, 0, NULL,
 547                  conn->callback_context);
 548
 549   /* Call UMODE command reply. */
 550   if (conn->local_entry->mode)
 551     silc_client_resume_command_callback(client, conn, SILC_COMMAND_UMODE,
 552                                         conn->local_entry->mode);
 553
 554   /* Call NICK command reply. */
 555   silc_client_resume_command_callback(client, conn, SILC_COMMAND_NICK,
 556                                       conn->local_entry,
 557                                       conn->local_entry->nickname,
 558                                       &conn->local_entry->id);
 559
 560   /* Call JOIN command replies for all joined channel */
 561   silc_idcache_get_all(conn->internal->channel_cache, &channels);
 562   silc_list_start(channels);
 563   while ((entry = silc_list_get(channels))) {
 564     SilcHashTableList htl;
 565     const char *cipher, *hmac;
 566
 567     channel = entry->context;
 568     cipher = (channel->internal.send_key ?
 569               silc_cipher_get_name(channel->internal.send_key) : NULL);
 570     hmac = (channel->internal.hmac ?
 571             silc_hmac_get_name(channel->internal.hmac) : NULL);
 572     silc_hash_table_list(channel->user_list, &htl);
 573     silc_client_resume_command_callback(client, conn, SILC_COMMAND_JOIN,
 574                                         channel->channel_name, channel,
 575                                         channel->mode, &htl, channel->topic,
 576                                         cipher, hmac, channel->founder_key,
 577                                         channel->channel_pubkeys,
 578                                         channel->user_limit);
 579     silc_hash_table_list_reset(&htl);
 580   }
 581
 582   conn->internal->registering = FALSE;
 583   silc_schedule_task_del_by_all(conn->internal->schedule, 0,
 584                                 silc_client_connect_timeout, conn);
 585   silc_free(resume->nickname);
 586   silc_free(resume);
 587
 588   return SILC_FSM_FINISH;
 589 }
 590
 591 /* Error resuming to network */
 592
 593 SILC_FSM_STATE(silc_client_st_resume_error)
 594 {
 595   SilcClientConnection conn = fsm_context;
 596   SilcClientResumeSession resume = state_context;
 597
 598   if (conn->internal->disconnected) {
 599     if (resume) {
 600       silc_free(resume->nickname);
 601       silc_free(resume);
 602     }
 603     return SILC_FSM_FINISH;
 604   }
 605
 606   SILC_LOG_DEBUG(("Error resuming to network"));
 607
 608   /* Signal to close connection */
 609   conn->internal->status = SILC_CLIENT_CONN_ERROR;
 610   if (!conn->internal->disconnected) {
 611     conn->internal->disconnected = TRUE;
 612     SILC_FSM_EVENT_SIGNAL(&conn->internal->wait_event);
 613   }
 614
 615   silc_schedule_task_del_by_all(conn->internal->schedule, 0,
 616                                 silc_client_connect_timeout, conn);
 617
 618   if (resume) {
 619     silc_free(resume->nickname);
 620     silc_free(resume);
 621   }
 622
 623   return SILC_FSM_FINISH;
 624 }
 625
 626 /* Generates the session detachment data. This data can be used later
 627    to resume back to the server. */
 628
 629 SilcBuffer silc_client_get_detach_data(SilcClient client,
 630                                        SilcClientConnection conn)
 631 {
 632   SilcBuffer detach;
 633   SilcHashTableList htl;
 634   SilcChannelUser chu;
 635   unsigned char id[64];
 636   SilcUInt32 id_len;
 637   int ret, ch_count;
 638
 639   SILC_LOG_DEBUG(("Creating detachment data"));
 640
 641   ch_count = silc_hash_table_count(conn->local_entry->channels);
 642   silc_id_id2str(conn->local_id, SILC_ID_CLIENT, id, sizeof(id), &id_len);
 643
 644   /* Save the nickname, Client ID and user mode in SILC network */
 645   detach = silc_buffer_alloc(0);
 646   if (!detach)
 647     return NULL;
 648   ret =
 649     silc_buffer_format(detach,
 650                        SILC_STR_ADVANCE,
 651                        SILC_STR_UI_SHORT(strlen(conn->local_entry->nickname)),
 652                        SILC_STR_DATA(conn->local_entry->nickname,
 653                                      strlen(conn->local_entry->nickname)),
 654                        SILC_STR_UI_SHORT(id_len),
 655                        SILC_STR_DATA(id, id_len),
 656                        SILC_STR_UI_INT(conn->local_entry->mode),
 657                        SILC_STR_UI_INT(ch_count),
 658                        SILC_STR_END);
 659   if (ret < 0) {
 660     silc_buffer_free(detach);
 661     return NULL;
 662   }
 663
 664   /* Save all joined channels */
 665   silc_hash_table_list(conn->local_entry->channels, &htl);
 666   while (silc_hash_table_get(&htl, NULL, (void *)&chu)) {
 667     unsigned char chid[32];
 668     SilcUInt32 chid_len;
 669
 670     silc_id_id2str(&chu->channel->id, SILC_ID_CHANNEL, chid, sizeof(chid),
 671                    &chid_len);
 672     silc_buffer_format(detach,
 673                        SILC_STR_ADVANCE,
 674                        SILC_STR_UI_SHORT(strlen(chu->channel->channel_name)),
 675                        SILC_STR_DATA(chu->channel->channel_name,
 676                                      strlen(chu->channel->channel_name)),
 677                        SILC_STR_UI_SHORT(chid_len),
 678                        SILC_STR_DATA(chid, chid_len),
 679                        SILC_STR_UI_INT(chu->channel->mode),
 680                        SILC_STR_END);
 681   }
 682   silc_hash_table_list_reset(&htl);
 683
 684   silc_buffer_start(detach);
 685   SILC_LOG_HEXDUMP(("Detach data"), silc_buffer_data(detach),
 686                    silc_buffer_len(detach));
 687
 688   return detach;
 689 }