apps/silcd/packet_send.c

   1 /*
   2
   3   packet_send.c
   4
   5   Author: Pekka Riikonen <priikone@silcnet.org>
   6
   7   Copyright (C) 1997 - 2001 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; either version 2 of the License, or
  12   (at your option) any later version.
  13
  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.
  18
  19 */
  20 /*
  21  * Server packet routines to send packets.
  22  */
  23 /* $Id$ */
  24
  25 #include "serverincludes.h"
  26 #include "server_internal.h"
  27
  28 /* Routine that sends packet or marks packet to be sent. This is used
  29    directly only in special cases. Normal cases should use
  30    silc_server_packet_send. Returns < 0 error. */
  31
  32 int silc_server_packet_send_real(SilcServer server,
  33                                  SilcSocketConnection sock,
  34                                  bool force_send)
  35 {
  36   int ret;
  37
  38   /* If disconnecting, ignore the data */
  39   if (SILC_IS_DISCONNECTING(sock))
  40     return -1;
  41
  42   /* If rekey protocol is active we must assure that all packets are
  43      sent through packet queue. */
  44   if (SILC_SERVER_IS_REKEY(sock))
  45     force_send = FALSE;
  46
  47   /* If outbound data is already pending do not force send */
  48   if (SILC_IS_OUTBUF_PENDING(sock))
  49     force_send = FALSE;
  50
  51   /* Send the packet */
  52   ret = silc_packet_send(sock, force_send);
  53   if (ret != -2)
  54     return ret;
  55
  56   /* Mark that there is some outgoing data available for this connection.
  57      This call sets the connection both for input and output (the input
  58      is set always and this call keeps the input setting, actually).
  59      Actual data sending is performed by silc_server_packet_process. */
  60   SILC_SET_CONNECTION_FOR_OUTPUT(server->schedule, sock->sock);
  61
  62   /* Mark to socket that data is pending in outgoing buffer. This flag
  63      is needed if new data is added to the buffer before the earlier
  64      put data is sent to the network. */
  65   SILC_SET_OUTBUF_PENDING(sock);
  66
  67   return 0;
  68 }
  69
  70 /* Assembles a new packet to be sent out to network. This doesn't actually
  71    send the packet but creates the packet and fills the outgoing data
  72    buffer and marks the packet ready to be sent to network. However, If
  73    argument force_send is TRUE the packet is sent immediately and not put
  74    to queue. Normal case is that the packet is not sent immediately. */
  75
  76 void silc_server_packet_send(SilcServer server,
  77                              SilcSocketConnection sock,
  78                              SilcPacketType type,
  79                              SilcPacketFlags flags,
  80                              unsigned char *data,
  81                              SilcUInt32 data_len,
  82                              bool force_send)
  83 {
  84   void *dst_id = NULL;
  85   SilcIdType dst_id_type = SILC_ID_NONE;
  86   SilcIDListData idata = (SilcIDListData)sock->user_data;
  87
  88   if (!sock)
  89     return;
  90
  91   /* If disconnecting, ignore the data */
  92   if (SILC_IS_DISCONNECTING(sock))
  93     return;
  94
  95   /* If entry is disabled do not sent anything. */
  96   if (idata && idata->status & SILC_IDLIST_STATUS_DISABLED)
  97     return;
  98
  99   /* Get data used in the packet sending, keys and stuff */
 100   switch(sock->type) {
 101   case SILC_SOCKET_TYPE_CLIENT:
 102     if (sock->user_data) {
 103       dst_id = ((SilcClientEntry)sock->user_data)->id;
 104       dst_id_type = SILC_ID_CLIENT;
 105     }
 106     break;
 107   case SILC_SOCKET_TYPE_SERVER:
 108   case SILC_SOCKET_TYPE_ROUTER:
 109     if (sock->user_data) {
 110       dst_id = ((SilcServerEntry)sock->user_data)->id;
 111       dst_id_type = SILC_ID_SERVER;
 112     }
 113     break;
 114   default:
 115     break;
 116   }
 117
 118   silc_server_packet_send_dest(server, sock, type, flags, dst_id,
 119                                dst_id_type, data, data_len, force_send);
 120 }
 121
 122 /* Assembles a new packet to be sent out to network. This doesn't actually
 123    send the packet but creates the packet and fills the outgoing data
 124    buffer and marks the packet ready to be sent to network. However, If
 125    argument force_send is TRUE the packet is sent immediately and not put
 126    to queue. Normal case is that the packet is not sent immediately.
 127    Destination information is sent as argument for this function. */
 128
 129 void silc_server_packet_send_dest(SilcServer server,
 130                                   SilcSocketConnection sock,
 131                                   SilcPacketType type,
 132                                   SilcPacketFlags flags,
 133                                   void *dst_id,
 134                                   SilcIdType dst_id_type,
 135                                   unsigned char *data,
 136                                   SilcUInt32 data_len,
 137                                   bool force_send)
 138 {
 139   SilcPacketContext packetdata;
 140   const SilcBufferStruct packet;
 141   SilcIDListData idata = (SilcIDListData)sock->user_data;
 142   SilcCipher cipher = NULL;
 143   SilcHmac hmac = NULL;
 144   SilcUInt32 sequence = 0;
 145   unsigned char *dst_id_data = NULL;
 146   SilcUInt32 dst_id_len = 0;
 147   int block_len = 0;
 148
 149   /* If disconnecting, ignore the data */
 150   if (SILC_IS_DISCONNECTING(sock))
 151     return;
 152
 153   /* If entry is disabled do not sent anything. */
 154   if (idata && idata->status & SILC_IDLIST_STATUS_DISABLED)
 155     return;
 156
 157   SILC_LOG_DEBUG(("Sending packet, type %d", type));
 158
 159   if (dst_id) {
 160     dst_id_data = silc_id_id2str(dst_id, dst_id_type);
 161     dst_id_len = silc_id_get_len(dst_id, dst_id_type);
 162   }
 163
 164   if (idata) {
 165     cipher = idata->send_key;
 166     hmac = idata->hmac_send;
 167     sequence = idata->psn_send++;
 168     block_len = silc_cipher_get_block_len(cipher);
 169   }
 170
 171   /* Set the packet context pointers */
 172   packetdata.type = type;
 173   packetdata.flags = flags;
 174   packetdata.src_id = silc_id_id2str(server->id, server->id_type);
 175   packetdata.src_id_len = silc_id_get_len(server->id, server->id_type);
 176   packetdata.src_id_type = server->id_type;
 177   packetdata.dst_id = dst_id_data;
 178   packetdata.dst_id_len = dst_id_len;
 179   packetdata.dst_id_type = dst_id_type;
 180   data_len = SILC_PACKET_DATALEN(data_len, (SILC_PACKET_HEADER_LEN +
 181                                             packetdata.src_id_len +
 182                                             packetdata.dst_id_len));
 183   packetdata.truelen = data_len + SILC_PACKET_HEADER_LEN +
 184     packetdata.src_id_len + dst_id_len;
 185   packetdata.padlen = SILC_PACKET_PADLEN(packetdata.truelen, block_len);
 186
 187   /* Create the outgoing packet */
 188   if (!silc_packet_assemble(&packetdata, NULL, cipher, hmac, sock,
 189                             data, data_len, (const SilcBuffer)&packet)) {
 190     SILC_LOG_ERROR(("Cannot assemble packet"));
 191     goto out;
 192   }
 193
 194   /* Encrypt the packet */
 195   silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&packet, packet.len);
 196
 197   SILC_LOG_HEXDUMP(("Outgoing packet (%d), len %d", sequence, packet.len),
 198                    packet.data, packet.len);
 199
 200   /* Now actually send the packet */
 201   silc_server_packet_send_real(server, sock, force_send);
 202
 203  out:
 204   if (packetdata.src_id)
 205     silc_free(packetdata.src_id);
 206   if (packetdata.dst_id)
 207     silc_free(packetdata.dst_id);
 208 }
 209
 210 /* Assembles a new packet to be sent out to network. This doesn't actually
 211    send the packet but creates the packet and fills the outgoing data
 212    buffer and marks the packet ready to be sent to network. However, If
 213    argument force_send is TRUE the packet is sent immediately and not put
 214    to queue. Normal case is that the packet is not sent immediately.
 215    The source and destination information is sent as argument for this
 216    function. */
 217
 218 void silc_server_packet_send_srcdest(SilcServer server,
 219                                      SilcSocketConnection sock,
 220                                      SilcPacketType type,
 221                                      SilcPacketFlags flags,
 222                                      void *src_id,
 223                                      SilcIdType src_id_type,
 224                                      void *dst_id,
 225                                      SilcIdType dst_id_type,
 226                                      unsigned char *data,
 227                                      SilcUInt32 data_len,
 228                                      bool force_send)
 229 {
 230   SilcPacketContext packetdata;
 231   const SilcBufferStruct packet;
 232   SilcIDListData idata;
 233   SilcCipher cipher = NULL;
 234   SilcHmac hmac = NULL;
 235   SilcUInt32 sequence = 0;
 236   unsigned char *dst_id_data = NULL;
 237   SilcUInt32 dst_id_len = 0;
 238   unsigned char *src_id_data = NULL;
 239   SilcUInt32 src_id_len = 0;
 240   int block_len = 0;
 241
 242   SILC_LOG_DEBUG(("Sending packet, type %d", type));
 243
 244   /* Get data used in the packet sending, keys and stuff */
 245   idata = (SilcIDListData)sock->user_data;
 246
 247   if (dst_id) {
 248     dst_id_data = silc_id_id2str(dst_id, dst_id_type);
 249     dst_id_len = silc_id_get_len(dst_id, dst_id_type);
 250   }
 251
 252   if (src_id) {
 253     src_id_data = silc_id_id2str(src_id, src_id_type);
 254     src_id_len = silc_id_get_len(src_id, src_id_type);
 255   }
 256
 257   if (idata) {
 258     cipher = idata->send_key;
 259     hmac = idata->hmac_send;
 260     sequence = idata->psn_send++;
 261     block_len = silc_cipher_get_block_len(cipher);
 262   }
 263
 264   /* Set the packet context pointers */
 265   packetdata.type = type;
 266   packetdata.flags = flags;
 267   packetdata.src_id = src_id_data;
 268   packetdata.src_id_len = src_id_len;
 269   packetdata.src_id_type = src_id_type;
 270   packetdata.dst_id = dst_id_data;
 271   packetdata.dst_id_len = dst_id_len;
 272   packetdata.dst_id_type = dst_id_type;
 273   data_len = SILC_PACKET_DATALEN(data_len, (SILC_PACKET_HEADER_LEN +
 274                                             packetdata.src_id_len +
 275                                             dst_id_len));
 276   packetdata.truelen = data_len + SILC_PACKET_HEADER_LEN +
 277     packetdata.src_id_len + dst_id_len;
 278   packetdata.padlen = SILC_PACKET_PADLEN(packetdata.truelen, block_len);
 279
 280   /* Create the outgoing packet */
 281   if (!silc_packet_assemble(&packetdata, NULL, cipher, hmac, sock, data,
 282                             data_len, (const SilcBuffer)&packet)) {
 283     SILC_LOG_ERROR(("Cannot assemble packe"));
 284     goto out;
 285   }
 286
 287   /* Encrypt the packet */
 288   silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&packet, packet.len);
 289
 290   SILC_LOG_HEXDUMP(("Outgoing packet (%d), len %d", sequence, packet.len),
 291                    packet.data, packet.len);
 292
 293   /* Now actually send the packet */
 294   silc_server_packet_send_real(server, sock, force_send);
 295
 296  out:
 297   if (packetdata.src_id)
 298     silc_free(packetdata.src_id);
 299   if (packetdata.dst_id)
 300     silc_free(packetdata.dst_id);
 301 }
 302
 303 /* Broadcast received packet to our primary route. This function is used
 304    by router to further route received broadcast packet. It is expected
 305    that the broadcast flag from the packet is checked before calling this
 306    function. This does not test or set the broadcast flag. */
 307
 308 void silc_server_packet_broadcast(SilcServer server,
 309                                   SilcSocketConnection sock,
 310                                   SilcPacketContext *packet)
 311 {
 312   SilcBuffer buffer = packet->buffer;
 313   SilcIDListData idata;
 314   void *id;
 315
 316   SILC_LOG_DEBUG(("Broadcasting received broadcast packet"));
 317
 318   /* If the packet is originated from our primary route we are
 319      not allowed to send the packet. */
 320   id = silc_id_str2id(packet->src_id, packet->src_id_len, packet->src_id_type);
 321   if (id && !SILC_ID_SERVER_COMPARE(id, server->router->id)) {
 322     const SilcBufferStruct p;
 323
 324     idata = (SilcIDListData)sock->user_data;
 325
 326     silc_buffer_push(buffer, buffer->data - buffer->head);
 327     if (!silc_packet_send_prepare(sock, 0, 0, buffer->len, idata->hmac_send,
 328                                   (const SilcBuffer)&p)) {
 329       SILC_LOG_ERROR(("Cannot send packet"));
 330       silc_free(id);
 331       return;
 332     }
 333     silc_buffer_put((SilcBuffer)&p, buffer->data, buffer->len);
 334     silc_packet_encrypt(idata->send_key, idata->hmac_send, idata->psn_send++,
 335                         (SilcBuffer)&p, p.len);
 336
 337     SILC_LOG_HEXDUMP(("Broadcasted packet (%d), len %d", idata->psn_send - 1,
 338                       p.len), p.data, p.len);
 339
 340     /* Now actually send the packet */
 341     silc_server_packet_send_real(server, sock, TRUE);
 342     silc_free(id);
 343     return;
 344   }
 345
 346   SILC_LOG_DEBUG(("Will not broadcast to primary route since it is the "
 347                   "original sender of this packet"));
 348   silc_free(id);
 349 }
 350
 351 /* Routes received packet to `sock'. This is used to route the packets that
 352    router receives but are not destined to it. */
 353
 354 void silc_server_packet_route(SilcServer server,
 355                               SilcSocketConnection sock,
 356                               SilcPacketContext *packet)
 357 {
 358   SilcBuffer buffer = packet->buffer;
 359   const SilcBufferStruct p;
 360   SilcIDListData idata;
 361
 362   SILC_LOG_DEBUG(("Routing received packet"));
 363
 364   idata = (SilcIDListData)sock->user_data;
 365
 366   silc_buffer_push(buffer, buffer->data - buffer->head);
 367   if (!silc_packet_send_prepare(sock, 0, 0, buffer->len, idata->hmac_send,
 368                                 (const SilcBuffer)&p)) {
 369     SILC_LOG_ERROR(("Cannot send packet"));
 370     return;
 371   }
 372   silc_buffer_put((SilcBuffer)&p, buffer->data, buffer->len);
 373   silc_packet_encrypt(idata->send_key, idata->hmac_send, idata->psn_send++,
 374                       (SilcBuffer)&p, p.len);
 375
 376   SILC_LOG_HEXDUMP(("Routed packet (%d), len %d", idata->psn_send - 1,
 377                    p.len), p.data, p.len);
 378
 379   /* Now actually send the packet */
 380   silc_server_packet_send_real(server, sock, TRUE);
 381 }
 382
 383 /* This routine can be used to send a packet to table of clients provided
 384    in `clients'. If `route' is FALSE the packet is routed only to local
 385    clients (for server locally connected, and for router local cell). */
 386
 387 void silc_server_packet_send_clients(SilcServer server,
 388                                      SilcClientEntry *clients,
 389                                      SilcUInt32 clients_count,
 390                                      SilcPacketType type,
 391                                      SilcPacketFlags flags,
 392                                      bool route,
 393                                      unsigned char *data,
 394                                      SilcUInt32 data_len,
 395                                      bool force_send)
 396 {
 397   SilcSocketConnection sock = NULL;
 398   SilcClientEntry client = NULL;
 399   SilcServerEntry *routed = NULL;
 400   SilcUInt32 routed_count = 0;
 401   bool gone = FALSE;
 402   int i, k;
 403
 404   SILC_LOG_DEBUG(("Sending packet to list of clients"));
 405
 406   /* Send to all clients in table */
 407   for (i = 0; i < clients_count; i++) {
 408     client = clients[i];
 409
 410     /* If client has router set it is not locally connected client and
 411        we will route the message to the router set in the client. Though,
 412        send locally connected server in all cases. */
 413     if (server->server_type == SILC_ROUTER && client->router &&
 414         ((!route && client->router->router == server->id_entry) || route)) {
 415
 416       /* Check if we have sent the packet to this route already */
 417       for (k = 0; k < routed_count; k++)
 418         if (routed[k] == client->router)
 419           break;
 420       if (k < routed_count)
 421         continue;
 422
 423       /* Route only once to router */
 424       sock = (SilcSocketConnection)client->router->connection;
 425       if (sock->type == SILC_SOCKET_TYPE_ROUTER) {
 426         if (gone)
 427           continue;
 428         gone = TRUE;
 429       }
 430
 431       /* Send the packet */
 432       silc_server_packet_send_dest(server, sock, type, flags,
 433                                    client->router->id, SILC_ID_SERVER,
 434                                    data, data_len, force_send);
 435
 436       /* Mark this route routed already */
 437       routed = silc_realloc(routed, sizeof(*routed) * (routed_count + 1));
 438       routed[routed_count++] = client->router;
 439       continue;
 440     }
 441
 442     if (client->router)
 443       continue;
 444
 445     /* Send to locally connected client */
 446     sock = (SilcSocketConnection)client->connection;
 447     silc_server_packet_send_dest(server, sock, type, flags,
 448                                  client->id, SILC_ID_CLIENT,
 449                                  data, data_len, force_send);
 450   }
 451
 452   silc_free(routed);
 453 }
 454
 455 /* Internal routine to actually create the channel packet and send it
 456    to network. This is common function in channel message sending. If
 457    `channel_message' is TRUE this encrypts the message as it is strictly
 458    a channel message. If FALSE normal encryption process is used. */
 459
 460 static void
 461 silc_server_packet_send_to_channel_real(SilcServer server,
 462                                         SilcSocketConnection sock,
 463                                         SilcPacketContext *packet,
 464                                         SilcCipher cipher,
 465                                         SilcHmac hmac,
 466                                         SilcUInt32 sequence,
 467                                         unsigned char *data,
 468                                         SilcUInt32 data_len,
 469                                         bool channel_message,
 470                                         bool force_send)
 471 {
 472   int block_len;
 473   const SilcBufferStruct p;
 474
 475   if (!sock)
 476     return;
 477
 478   data_len = SILC_PACKET_DATALEN(data_len, (SILC_PACKET_HEADER_LEN +
 479                                             packet->src_id_len +
 480                                             packet->dst_id_len));
 481   packet->truelen = data_len + SILC_PACKET_HEADER_LEN +
 482     packet->src_id_len + packet->dst_id_len;
 483
 484   block_len = cipher ? silc_cipher_get_block_len(cipher) : 0;
 485   if (channel_message)
 486     packet->padlen = SILC_PACKET_PADLEN((SILC_PACKET_HEADER_LEN +
 487                                          packet->src_id_len +
 488                                          packet->dst_id_len), block_len);
 489   else
 490     packet->padlen = SILC_PACKET_PADLEN(packet->truelen, block_len);
 491
 492   /* Put the data to buffer, assemble and encrypt the packet. The packet
 493      is encrypted with normal session key shared with the client, unless
 494      the `channel_message' is TRUE. */
 495   if (!silc_packet_assemble(packet, NULL, cipher, hmac, sock, data,
 496                             data_len, (const SilcBuffer)&p)) {
 497     SILC_LOG_ERROR(("Cannot assemble packet"));
 498     return;
 499   }
 500
 501   if (channel_message)
 502     silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&p,
 503                         SILC_PACKET_HEADER_LEN + packet->src_id_len +
 504                         packet->dst_id_len + packet->padlen);
 505   else
 506     silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&p, p.len);
 507
 508   SILC_LOG_HEXDUMP(("Channel packet (%d), len %d", sequence, p.len),
 509                    p.data, p.len);
 510
 511   /* Now actually send the packet */
 512   silc_server_packet_send_real(server, sock, force_send);
 513 }
 514
 515 /* This routine is used by the server to send packets to channel. The
 516    packet sent with this function is distributed to all clients on
 517    the channel. Usually this is used to send notify messages to the
 518    channel, things like notify about new user joining to the channel.
 519    If `route' is FALSE then the packet is sent only locally and will not
 520    be routed anywhere (for router locally means cell wide). If `sender'
 521    is provided then the packet is not sent to that connection since it
 522    originally came from it. If `send_to_clients' is FALSE then the
 523    packet is not sent clients, only servers. */
 524
 525 void silc_server_packet_send_to_channel(SilcServer server,
 526                                         SilcSocketConnection sender,
 527                                         SilcChannelEntry channel,
 528                                         SilcPacketType type,
 529                                         bool route,
 530                                         unsigned char *data,
 531                                         SilcUInt32 data_len,
 532                                         bool force_send)
 533 {
 534   SilcSocketConnection sock = NULL;
 535   SilcPacketContext packetdata;
 536   SilcClientEntry client = NULL;
 537   SilcServerEntry *routed = NULL;
 538   SilcChannelClientEntry chl;
 539   SilcHashTableList htl;
 540   SilcIDListData idata;
 541   SilcUInt32 routed_count = 0;
 542   bool gone = FALSE;
 543   int k;
 544
 545   /* This doesn't send channel message packets */
 546   assert(type != SILC_PACKET_CHANNEL_MESSAGE);
 547
 548   SILC_LOG_DEBUG(("Sending packet to channel"));
 549
 550   /* Set the packet context pointers. */
 551   packetdata.flags = 0;
 552   packetdata.type = type;
 553   packetdata.src_id = silc_id_id2str(server->id, SILC_ID_SERVER);
 554   packetdata.src_id_len = silc_id_get_len(server->id, SILC_ID_SERVER);
 555   packetdata.src_id_type = SILC_ID_SERVER;
 556   packetdata.dst_id = silc_id_id2str(channel->id, SILC_ID_CHANNEL);
 557   packetdata.dst_id_len = silc_id_get_len(channel->id, SILC_ID_CHANNEL);
 558   packetdata.dst_id_type = SILC_ID_CHANNEL;
 559
 560   /* If there are global users in the channel we will send the message
 561      first to our router for further routing. */
 562   if (route && server->server_type != SILC_ROUTER && !server->standalone &&
 563       channel->global_users) {
 564     SilcServerEntry router;
 565
 566     /* Get data used in packet header encryption, keys and stuff. */
 567     router = server->router;
 568     sock = (SilcSocketConnection)router->connection;
 569     idata = (SilcIDListData)router;
 570
 571     if (sock != sender) {
 572       SILC_LOG_DEBUG(("Sending packet to router for routing"));
 573
 574       silc_server_packet_send_to_channel_real(server, sock, &packetdata,
 575                                               idata->send_key,
 576                                               idata->hmac_send,
 577                                               idata->psn_send++,
 578                                               data, data_len, FALSE,
 579                                               force_send);
 580     }
 581   }
 582
 583   routed = silc_calloc(silc_hash_table_count(channel->user_list),
 584                        sizeof(*routed));
 585
 586   /* Send the message to clients on the channel's client list. */
 587   silc_hash_table_list(channel->user_list, &htl);
 588   while (silc_hash_table_get(&htl, NULL, (void *)&chl)) {
 589     client = chl->client;
 590     if (!client)
 591       continue;
 592
 593     /* If client has router set it is not locally connected client and
 594        we will route the message to the router set in the client. Though,
 595        send locally connected server in all cases. */
 596     if (server->server_type == SILC_ROUTER && client->router &&
 597         ((!route && client->router->router == server->id_entry) || route)) {
 598
 599       /* Check if we have sent the packet to this route already */
 600       for (k = 0; k < routed_count; k++)
 601         if (routed[k] == client->router)
 602           break;
 603       if (k < routed_count)
 604         continue;
 605
 606       /* Get data used in packet header encryption, keys and stuff. */
 607       sock = (SilcSocketConnection)client->router->connection;
 608       idata = (SilcIDListData)client->router;
 609
 610       if (sender && sock == sender)
 611         continue;
 612
 613       /* Route only once to router. Protocol prohibits sending channel
 614          messages to more than one router. */
 615       if (sock->type == SILC_SOCKET_TYPE_ROUTER) {
 616         if (gone)
 617           continue;
 618         gone = TRUE;
 619       }
 620
 621       /* Send the packet */
 622       silc_server_packet_send_to_channel_real(server, sock, &packetdata,
 623                                               idata->send_key,
 624                                               idata->hmac_send,
 625                                               idata->psn_send++,
 626                                               data, data_len, FALSE,
 627                                               force_send);
 628
 629       /* Mark this route routed already */
 630       routed[routed_count++] = client->router;
 631       continue;
 632     }
 633
 634     if (client->router)
 635       continue;
 636
 637     /* Send to locally connected client */
 638
 639     /* Get data used in packet header encryption, keys and stuff. */
 640     sock = (SilcSocketConnection)client->connection;
 641     idata = (SilcIDListData)client;
 642
 643     if (!sock || (sender && sock == sender))
 644       continue;
 645
 646     /* Send the packet */
 647     silc_server_packet_send_to_channel_real(server, sock, &packetdata,
 648                                             idata->send_key,
 649                                             idata->hmac_send,
 650                                             idata->psn_send++,
 651                                             data, data_len, FALSE,
 652                                             force_send);
 653   }
 654
 655   silc_hash_table_list_reset(&htl);
 656   silc_free(routed);
 657   silc_free(packetdata.src_id);
 658   silc_free(packetdata.dst_id);
 659 }
 660
 661 /* This checks whether the relayed packet came from router. If it did
 662    then we'll need to encrypt it with the channel key. This is called
 663    from the silc_server_packet_relay_to_channel. */
 664
 665 static bool
 666 silc_server_packet_relay_to_channel_encrypt(SilcServer server,
 667                                             SilcSocketConnection sock,
 668                                             SilcChannelEntry channel,
 669                                             unsigned char *data,
 670                                             unsigned int data_len)
 671 {
 672   /* If we are router and the packet came from router and private key
 673      has not been set for the channel then we must encrypt the packet
 674      as it was decrypted with the session key shared between us and the
 675      router which sent it. This is so, because cells does not share the
 676      same channel key. */
 677   if (server->server_type == SILC_ROUTER &&
 678       sock->type == SILC_SOCKET_TYPE_ROUTER &&
 679       !(channel->mode & SILC_CHANNEL_MODE_PRIVKEY) &&
 680       channel->channel_key) {
 681     SilcUInt32 mac_len = silc_hmac_len(channel->hmac);
 682     SilcUInt32 iv_len = silc_cipher_get_block_len(channel->channel_key);
 683
 684     if (data_len <= mac_len + iv_len) {
 685       SILC_LOG_WARNING(("Corrupted channel message, cannot relay it"));
 686       return FALSE;
 687     }
 688
 689     memcpy(channel->iv, data + (data_len - iv_len), iv_len);
 690     silc_channel_message_payload_encrypt(data, data_len - iv_len - mac_len,
 691                                          data_len, channel->iv, iv_len,
 692                                          channel->channel_key, channel->hmac);
 693   }
 694
 695   return TRUE;
 696 }
 697
 698 /* This routine is explicitly used to relay messages to some channel.
 699    Packets sent with this function we have received earlier and are
 700    totally encrypted. This just sends the packet to all clients on
 701    the channel. If the sender of the packet is someone on the channel
 702    the message will not be sent to that client. The SILC Packet header
 703    is encrypted with the session key shared between us and the client.
 704    MAC is also computed before encrypting the header. Rest of the
 705    packet will be untouched. */
 706
 707 void silc_server_packet_relay_to_channel(SilcServer server,
 708                                          SilcSocketConnection sender_sock,
 709                                          SilcChannelEntry channel,
 710                                          void *sender_id,
 711                                          SilcIdType sender_type,
 712                                          SilcClientEntry sender_entry,
 713                                          unsigned char *data,
 714                                          SilcUInt32 data_len,
 715                                          bool force_send)
 716 {
 717   SilcSocketConnection sock = NULL;
 718   SilcPacketContext packetdata;
 719   SilcClientEntry client = NULL;
 720   SilcServerEntry *routed = NULL;
 721   SilcChannelClientEntry chl;
 722   SilcUInt32 routed_count = 0;
 723   SilcIDListData idata;
 724   SilcHashTableList htl;
 725   bool gone = FALSE;
 726   int k;
 727
 728   SILC_LOG_DEBUG(("Relaying packet to channel"));
 729
 730   /* This encrypts the packet, if needed. It will be encrypted if
 731      it came from the router thus it needs to be encrypted with the
 732      channel key. If the channel key does not exist, then we know we
 733      don't have a single local user on the channel. */
 734   if (!silc_server_packet_relay_to_channel_encrypt(server, sender_sock,
 735                                                    channel, data,
 736                                                    data_len))
 737     return;
 738
 739   /* Set the packet context pointers. */
 740   packetdata.flags = 0;
 741   packetdata.type = SILC_PACKET_CHANNEL_MESSAGE;
 742   packetdata.src_id = silc_id_id2str(sender_id, sender_type);
 743   packetdata.src_id_len = silc_id_get_len(sender_id, sender_type);
 744   packetdata.src_id_type = sender_type;
 745   packetdata.dst_id = silc_id_id2str(channel->id, SILC_ID_CHANNEL);
 746   packetdata.dst_id_len = silc_id_get_len(channel->id, SILC_ID_CHANNEL);
 747   packetdata.dst_id_type = SILC_ID_CHANNEL;
 748
 749   /* If there are global users in the channel we will send the message
 750      first to our router for further routing. */
 751   if (server->server_type != SILC_ROUTER && !server->standalone &&
 752       channel->global_users) {
 753     SilcServerEntry router = server->router;
 754
 755     /* Check that the sender is not our router. */
 756     if (sender_sock != (SilcSocketConnection)router->connection) {
 757
 758       /* Get data used in packet header encryption, keys and stuff. */
 759       sock = (SilcSocketConnection)router->connection;
 760       idata = (SilcIDListData)router;
 761
 762       SILC_LOG_DEBUG(("Sending channel message to router for routing"));
 763
 764       silc_server_packet_send_to_channel_real(server, sock, &packetdata,
 765                                               idata->send_key,
 766                                               idata->hmac_send,
 767                                               idata->psn_send++,
 768                                               data, data_len, TRUE,
 769                                               force_send);
 770     }
 771   }
 772
 773   routed = silc_calloc(silc_hash_table_count(channel->user_list),
 774                        sizeof(*routed));
 775
 776   /* Assure we won't route the message back to the sender's way. */
 777   if (sender_entry->router)
 778     routed[routed_count++] = sender_entry->router;
 779
 780   /* Send the message to clients on the channel's client list. */
 781   silc_hash_table_list(channel->user_list, &htl);
 782   while (silc_hash_table_get(&htl, NULL, (void *)&chl)) {
 783     client = chl->client;
 784     if (!client || client == sender_entry)
 785       continue;
 786
 787     /* If the client has set router it means that it is not locally
 788        connected client and we will route the packet further. */
 789     if (server->server_type == SILC_ROUTER && client->router) {
 790
 791       /* Check if we have sent the packet to this route already */
 792       for (k = 0; k < routed_count; k++)
 793         if (routed[k] == client->router)
 794           break;
 795       if (k < routed_count)
 796         continue;
 797
 798       /* Get data used in packet header encryption, keys and stuff. */
 799       sock = (SilcSocketConnection)client->router->connection;
 800       idata = (SilcIDListData)client->router;
 801
 802       /* Check if the sender socket is the same as this client's router
 803          socket. */
 804       if (sender_sock && sock == sender_sock)
 805         continue;
 806
 807       SILC_LOG_DEBUG(("Relaying packet to client ID(%s) %s (%s)",
 808                       silc_id_render(client->id, SILC_ID_CLIENT),
 809                       sock->hostname, sock->ip));
 810
 811       /* Mark this route routed already. */
 812       routed[routed_count++] = client->router;
 813
 814       if (sock->type == SILC_SOCKET_TYPE_ROUTER) {
 815         /* The remote connection is router then we'll decrypt the
 816            channel message and re-encrypt it with the session key shared
 817            between us and the remote router. This is done because the
 818            channel keys are cell specific and we have different channel
 819            key than the remote router has. */
 820
 821         /* Route only once to router. Protocol prohibits sending channel
 822            messages to more than one router. */
 823         if (gone)
 824           continue;
 825         gone = TRUE;
 826
 827         SILC_LOG_DEBUG(("Remote is router, encrypt with session key"));
 828
 829         /* If private key mode is not set then decrypt the packet
 830            and re-encrypt it */
 831         if (!(channel->mode & SILC_CHANNEL_MODE_PRIVKEY) &&
 832             channel->channel_key) {
 833           unsigned char tmp[SILC_PACKET_MAX_LEN];
 834
 835           if (data_len > SILC_PACKET_MAX_LEN)
 836             data_len = SILC_PACKET_MAX_LEN;
 837           memcpy(tmp, data, data_len);
 838
 839           /* Decrypt the channel message (we don't check the MAC) */
 840           silc_channel_message_payload_decrypt(tmp, data_len,
 841                                                channel->channel_key, NULL);
 842
 843           /* Now re-encrypt and send it to the router */
 844           silc_server_packet_send_srcdest(server, sock,
 845                                           SILC_PACKET_CHANNEL_MESSAGE, 0,
 846                                           sender_id, sender_type,
 847                                           channel->id, SILC_ID_CHANNEL,
 848                                           tmp, data_len, force_send);
 849         } else {
 850           /* Private key mode is set, we don't have the channel key, so
 851              just re-encrypt the entire packet and send it to the router. */
 852           silc_server_packet_send_srcdest(server, sock,
 853                                           SILC_PACKET_CHANNEL_MESSAGE, 0,
 854                                           sender_id, sender_type,
 855                                           channel->id, SILC_ID_CHANNEL,
 856                                           data, data_len, force_send);
 857         }
 858       } else {
 859         /* Send the packet to normal server */
 860         silc_server_packet_send_to_channel_real(server, sock, &packetdata,
 861                                                 idata->send_key,
 862                                                 idata->hmac_send,
 863                                                 idata->psn_send++,
 864                                                 data, data_len, TRUE,
 865                                                 force_send);
 866       }
 867
 868       continue;
 869     }
 870
 871     if (client->router)
 872       continue;
 873
 874     /* Get data used in packet header encryption, keys and stuff. */
 875     sock = (SilcSocketConnection)client->connection;
 876     idata = (SilcIDListData)client;
 877
 878     if (!sock || (sender_sock && sock == sender_sock))
 879       continue;
 880
 881     SILC_LOG_DEBUG(("Sending packet to client ID(%s) %s (%s)",
 882                     silc_id_render(client->id, SILC_ID_CLIENT),
 883                     sock->hostname, sock->ip));
 884
 885     /* Send the packet */
 886     silc_server_packet_send_to_channel_real(server, sock, &packetdata,
 887                                             idata->send_key,
 888                                             idata->hmac_send,
 889                                             idata->psn_send++,
 890                                             data, data_len, TRUE,
 891                                             force_send);
 892   }
 893
 894   silc_hash_table_list_reset(&htl);
 895   silc_free(routed);
 896   silc_free(packetdata.src_id);
 897   silc_free(packetdata.dst_id);
 898 }
 899
 900 /* This function is used to send packets strictly to all local clients
 901    on a particular channel.  This is used for example to distribute new
 902    channel key to all our locally connected clients on the channel.
 903    The packets are always encrypted with the session key shared between
 904    the client, this means these are not _to the channel_ but _to the client_
 905    on the channel. */
 906
 907 void silc_server_packet_send_local_channel(SilcServer server,
 908                                            SilcChannelEntry channel,
 909                                            SilcPacketType type,
 910                                            SilcPacketFlags flags,
 911                                            unsigned char *data,
 912                                            SilcUInt32 data_len,
 913                                            bool force_send)
 914 {
 915   SilcChannelClientEntry chl;
 916   SilcHashTableList htl;
 917   SilcSocketConnection sock = NULL;
 918
 919   SILC_LOG_DEBUG(("Start"));
 920
 921   /* Send the message to clients on the channel's client list. */
 922   silc_hash_table_list(channel->user_list, &htl);
 923   while (silc_hash_table_get(&htl, NULL, (void *)&chl)) {
 924     if (chl->client && !chl->client->router) {
 925       sock = (SilcSocketConnection)chl->client->connection;
 926
 927       /* Send the packet to the client */
 928       silc_server_packet_send_dest(server, sock, type, flags, chl->client->id,
 929                                    SILC_ID_CLIENT, data, data_len,
 930                                    force_send);
 931     }
 932   }
 933   silc_hash_table_list_reset(&htl);
 934 }
 935
 936 /* Routine used to send (relay, route) private messages to some destination.
 937    If the private message key does not exist then the message is re-encrypted,
 938    otherwise we just pass it along. This really is not used to send new
 939    private messages (as server does not send them) but to relay received
 940    private messages. */
 941
 942 void silc_server_send_private_message(SilcServer server,
 943                                       SilcSocketConnection dst_sock,
 944                                       SilcCipher cipher,
 945                                       SilcHmac hmac,
 946                                       SilcUInt32 sequence,
 947                                       SilcPacketContext *packet)
 948 {
 949   SilcBuffer buffer = packet->buffer;
 950   const SilcBufferStruct p;
 951
 952   silc_buffer_push(buffer, SILC_PACKET_HEADER_LEN + packet->src_id_len
 953                    + packet->dst_id_len + packet->padlen);
 954   if (!silc_packet_send_prepare(dst_sock, 0, 0, buffer->len, hmac,
 955                                 (const SilcBuffer)&p)) {
 956     SILC_LOG_ERROR(("Cannot send packet"));
 957     return;
 958   }
 959   silc_buffer_put((SilcBuffer)&p, buffer->data, buffer->len);
 960
 961   /* Re-encrypt and send if private messge key does not exist */
 962   if (!(packet->flags & SILC_PACKET_FLAG_PRIVMSG_KEY)) {
 963     /* Re-encrypt packet */
 964     silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&p, buffer->len);
 965   } else {
 966     /* Key exist so encrypt just header and send it */
 967     silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&p,
 968                         SILC_PACKET_HEADER_LEN + packet->src_id_len +
 969                         packet->dst_id_len + packet->padlen);
 970   }
 971
 972   /* Send the packet */
 973   silc_server_packet_send_real(server, dst_sock, FALSE);
 974 }
 975
 976 /* Sends current motd to client */
 977
 978 void silc_server_send_motd(SilcServer server,
 979                            SilcSocketConnection sock)
 980 {
 981   char *motd, *motd_file = NULL;
 982   SilcUInt32 motd_len;
 983
 984   if (server->config)
 985     motd_file = server->config->server_info->motd_file;
 986
 987   if (motd_file) {
 988     motd = silc_file_readfile(motd_file, &motd_len);
 989     if (!motd)
 990       return;
 991
 992     silc_server_send_notify(server, sock, FALSE, SILC_NOTIFY_TYPE_MOTD, 1,
 993                             motd, motd_len);
 994     silc_free(motd);
 995   }
 996 }
 997
 998 /* Sends error message. Error messages may or may not have any
 999    implications. */
1000
1001 void silc_server_send_error(SilcServer server,
1002                             SilcSocketConnection sock,
1003                             const char *fmt, ...)
1004 {
1005   va_list ap;
1006   unsigned char buf[4096];
1007
1008   memset(buf, 0, sizeof(buf));
1009   va_start(ap, fmt);
1010   vsprintf(buf, fmt, ap);
1011   va_end(ap);
1012
1013   silc_server_packet_send(server, sock, SILC_PACKET_ERROR, 0,
1014                           buf, strlen(buf), FALSE);
1015 }
1016
1017 /* Sends notify message. If format is TRUE the variable arguments are
1018    formatted and the formatted string is sent as argument payload. If it is
1019    FALSE then each argument is sent as separate argument and their format
1020    in the argument list must be { argument data, argument length }. */
1021
1022 void silc_server_send_notify(SilcServer server,
1023                              SilcSocketConnection sock,
1024                              bool broadcast,
1025                              SilcNotifyType type,
1026                              SilcUInt32 argc, ...)
1027 {
1028   va_list ap;
1029   SilcBuffer packet;
1030
1031   va_start(ap, argc);
1032
1033   packet = silc_notify_payload_encode(type, argc, ap);
1034   silc_server_packet_send(server, sock, SILC_PACKET_NOTIFY,
1035                           broadcast ? SILC_PACKET_FLAG_BROADCAST : 0,
1036                           packet->data, packet->len, FALSE);
1037
1038   /* Send to backup routers if this is being broadcasted to primary
1039      router. */
1040   if (server->router && server->router->connection &&
1041       sock == server->router->connection && broadcast)
1042     silc_server_backup_send(server, NULL, SILC_PACKET_NOTIFY, 0,
1043                             packet->data, packet->len, FALSE, TRUE);
1044
1045   silc_buffer_free(packet);
1046   va_end(ap);
1047 }
1048
1049 /* Sends notify message and gets the arguments from the `args' Argument
1050    Payloads. */
1051
1052 void silc_server_send_notify_args(SilcServer server,
1053                                   SilcSocketConnection sock,
1054                                   bool broadcast,
1055                                   SilcNotifyType type,
1056                                   SilcUInt32 argc,
1057                                   SilcBuffer args)
1058 {
1059   SilcBuffer packet;
1060
1061   packet = silc_notify_payload_encode_args(type, argc, args);
1062   silc_server_packet_send(server, sock, SILC_PACKET_NOTIFY,
1063                           broadcast ? SILC_PACKET_FLAG_BROADCAST : 0,
1064                           packet->data, packet->len, FALSE);
1065   silc_buffer_free(packet);
1066 }
1067
1068 /* Send CHANNEL_CHANGE notify type. This tells the receiver to replace the
1069    `old_id' with the `new_id'. */
1070
1071 void silc_server_send_notify_channel_change(SilcServer server,
1072                                             SilcSocketConnection sock,
1073                                             bool broadcast,
1074                                             SilcChannelID *old_id,
1075                                             SilcChannelID *new_id)
1076 {
1077   SilcBuffer idp1, idp2;
1078
1079   idp1 = silc_id_payload_encode((void *)old_id, SILC_ID_CHANNEL);
1080   idp2 = silc_id_payload_encode((void *)new_id, SILC_ID_CHANNEL);
1081
1082   silc_server_send_notify(server, sock, broadcast,
1083                           SILC_NOTIFY_TYPE_CHANNEL_CHANGE,
1084                           2, idp1->data, idp1->len, idp2->data, idp2->len);
1085   silc_buffer_free(idp1);
1086   silc_buffer_free(idp2);
1087 }
1088
1089 /* Send NICK_CHANGE notify type. This tells the receiver to replace the
1090    `old_id' with the `new_id'. */
1091
1092 void silc_server_send_notify_nick_change(SilcServer server,
1093                                          SilcSocketConnection sock,
1094                                          bool broadcast,
1095                                          SilcClientID *old_id,
1096                                          SilcClientID *new_id)
1097 {
1098   SilcBuffer idp1, idp2;
1099
1100   idp1 = silc_id_payload_encode((void *)old_id, SILC_ID_CLIENT);
1101   idp2 = silc_id_payload_encode((void *)new_id, SILC_ID_CLIENT);
1102
1103   silc_server_send_notify(server, sock, broadcast,
1104                           SILC_NOTIFY_TYPE_NICK_CHANGE,
1105                           2, idp1->data, idp1->len, idp2->data, idp2->len);
1106   silc_buffer_free(idp1);
1107   silc_buffer_free(idp2);
1108 }
1109
1110 /* Sends JOIN notify type. This tells that new client by `client_id' ID
1111    has joined to the `channel'. */
1112
1113 void silc_server_send_notify_join(SilcServer server,
1114                                   SilcSocketConnection sock,
1115                                   bool broadcast,
1116                                   SilcChannelEntry channel,
1117                                   SilcClientID *client_id)
1118 {
1119   SilcBuffer idp1, idp2;
1120
1121   idp1 = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1122   idp2 = silc_id_payload_encode((void *)channel->id, SILC_ID_CHANNEL);
1123   silc_server_send_notify(server, sock, broadcast, SILC_NOTIFY_TYPE_JOIN,
1124                           2, idp1->data, idp1->len,
1125                           idp2->data, idp2->len);
1126   silc_buffer_free(idp1);
1127   silc_buffer_free(idp2);
1128 }
1129
1130 /* Sends LEAVE notify type. This tells that `client_id' has left the
1131    `channel'. The Notify packet is always destined to the channel. */
1132
1133 void silc_server_send_notify_leave(SilcServer server,
1134                                    SilcSocketConnection sock,
1135                                    bool broadcast,
1136                                    SilcChannelEntry channel,
1137                                    SilcClientID *client_id)
1138 {
1139   SilcBuffer idp;
1140
1141   idp = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1142   silc_server_send_notify_dest(server, sock, broadcast, (void *)channel->id,
1143                                SILC_ID_CHANNEL, SILC_NOTIFY_TYPE_LEAVE,
1144                                1, idp->data, idp->len);
1145   silc_buffer_free(idp);
1146 }
1147
1148 /* Sends CMODE_CHANGE notify type. This tells that `client_id' changed the
1149    `channel' mode to `mode. The Notify packet is always destined to
1150    the channel. */
1151
1152 void silc_server_send_notify_cmode(SilcServer server,
1153                                    SilcSocketConnection sock,
1154                                    bool broadcast,
1155                                    SilcChannelEntry channel,
1156                                    SilcUInt32 mode_mask,
1157                                    void *id, SilcIdType id_type,
1158                                    char *cipher, char *hmac,
1159                                    char *passphrase)
1160 {
1161   SilcBuffer idp;
1162   unsigned char mode[4];
1163
1164   idp = silc_id_payload_encode((void *)id, id_type);
1165   SILC_PUT32_MSB(mode_mask, mode);
1166
1167   silc_server_send_notify_dest(server, sock, broadcast, (void *)channel->id,
1168                                SILC_ID_CHANNEL, SILC_NOTIFY_TYPE_CMODE_CHANGE,
1169                                5, idp->data, idp->len,
1170                                mode, 4,
1171                                cipher, cipher ? strlen(cipher) : 0,
1172                                hmac, hmac ? strlen(hmac) : 0,
1173                                passphrase, passphrase ?
1174                                strlen(passphrase) : 0);
1175   silc_buffer_free(idp);
1176 }
1177
1178 /* Sends CUMODE_CHANGE notify type. This tells that `client_id' changed the
1179    `target' client's mode on `channel'. The notify packet is always
1180    destined to the channel. */
1181
1182 void silc_server_send_notify_cumode(SilcServer server,
1183                                     SilcSocketConnection sock,
1184                                     bool broadcast,
1185                                     SilcChannelEntry channel,
1186                                     SilcUInt32 mode_mask,
1187                                     void *id, SilcIdType id_type,
1188                                     SilcClientID *target)
1189 {
1190   SilcBuffer idp1, idp2;
1191   unsigned char mode[4];
1192
1193   idp1 = silc_id_payload_encode((void *)id, id_type);
1194   idp2 = silc_id_payload_encode((void *)target, SILC_ID_CLIENT);
1195   SILC_PUT32_MSB(mode_mask, mode);
1196
1197   silc_server_send_notify_dest(server, sock, broadcast, (void *)channel->id,
1198                                SILC_ID_CHANNEL,
1199                                SILC_NOTIFY_TYPE_CUMODE_CHANGE, 3,
1200                                idp1->data, idp1->len,
1201                                mode, 4,
1202                                idp2->data, idp2->len);
1203   silc_buffer_free(idp1);
1204   silc_buffer_free(idp2);
1205 }
1206
1207 /* Sends SIGNOFF notify type. This tells that `client_id' client has
1208    left SILC network. This function is used only between server and router
1209    traffic. This is not used to send the notify to the channel for
1210    client. The `message may be NULL. */
1211
1212 void silc_server_send_notify_signoff(SilcServer server,
1213                                      SilcSocketConnection sock,
1214                                      bool broadcast,
1215                                      SilcClientID *client_id,
1216                                      const char *message)
1217 {
1218   SilcBuffer idp;
1219
1220   idp = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1221   silc_server_send_notify(server, sock, broadcast,
1222                           SILC_NOTIFY_TYPE_SIGNOFF,
1223                           message ? 2 : 1, idp->data, idp->len,
1224                           message, message ? strlen(message): 0);
1225   silc_buffer_free(idp);
1226 }
1227
1228 /* Sends TOPIC_SET notify type. This tells that `id' changed
1229    the `channel's topic to `topic'. The Notify packet is always destined
1230    to the channel. This function is used to send the topic set notifies
1231    between routers. */
1232
1233 void silc_server_send_notify_topic_set(SilcServer server,
1234                                        SilcSocketConnection sock,
1235                                        bool broadcast,
1236                                        SilcChannelEntry channel,
1237                                        void *id, SilcIdType id_type,
1238                                        char *topic)
1239 {
1240   SilcBuffer idp;
1241
1242   idp = silc_id_payload_encode(id, id_type);
1243   silc_server_send_notify_dest(server, sock, broadcast,
1244                                (void *)channel->id, SILC_ID_CHANNEL,
1245                                SILC_NOTIFY_TYPE_TOPIC_SET,
1246                                topic ? 2 : 1,
1247                                idp->data, idp->len,
1248                                topic, topic ? strlen(topic) : 0);
1249   silc_buffer_free(idp);
1250 }
1251
1252 /* Send KICKED notify type. This tells that the `client_id' on `channel'
1253    was kicked off the channel.  The `comment' may indicate the reason
1254    for the kicking. This function is used only between server and router
1255    traffic. */
1256
1257 void silc_server_send_notify_kicked(SilcServer server,
1258                                     SilcSocketConnection sock,
1259                                     bool broadcast,
1260                                     SilcChannelEntry channel,
1261                                     SilcClientID *client_id,
1262                                     SilcClientID *kicker,
1263                                     char *comment)
1264 {
1265   SilcBuffer idp1;
1266   SilcBuffer idp2;
1267
1268   idp1 = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1269   idp2 = silc_id_payload_encode((void *)kicker, SILC_ID_CLIENT);
1270   silc_server_send_notify_dest(server, sock, broadcast, (void *)channel->id,
1271                                SILC_ID_CHANNEL, SILC_NOTIFY_TYPE_KICKED, 3,
1272                                idp1->data, idp1->len,
1273                                comment, comment ? strlen(comment) : 0,
1274                                idp2->data, idp2->len);
1275   silc_buffer_free(idp1);
1276   silc_buffer_free(idp2);
1277 }
1278
1279 /* Send KILLED notify type. This tells that the `client_id' client was
1280    killed from the network.  The `comment' may indicate the reason
1281    for the killing. */
1282
1283 void silc_server_send_notify_killed(SilcServer server,
1284                                     SilcSocketConnection sock,
1285                                     bool broadcast,
1286                                     SilcClientID *client_id,
1287                                     char *comment)
1288 {
1289   SilcBuffer idp;
1290
1291   idp = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1292   silc_server_send_notify_dest(server, sock, broadcast, (void *)client_id,
1293                                SILC_ID_CLIENT, SILC_NOTIFY_TYPE_KILLED,
1294                                comment ? 2 : 1, idp->data, idp->len,
1295                                comment, comment ? strlen(comment) : 0);
1296   silc_buffer_free(idp);
1297 }
1298
1299 /* Sends UMODE_CHANGE notify type. This tells that `client_id' client's
1300    user mode in the SILC Network was changed. This function is used to
1301    send the packet between routers as broadcast packet. */
1302
1303 void silc_server_send_notify_umode(SilcServer server,
1304                                    SilcSocketConnection sock,
1305                                    bool broadcast,
1306                                    SilcClientID *client_id,
1307                                    SilcUInt32 mode_mask)
1308 {
1309   SilcBuffer idp;
1310   unsigned char mode[4];
1311
1312   idp = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1313   SILC_PUT32_MSB(mode_mask, mode);
1314
1315   silc_server_send_notify(server, sock, broadcast,
1316                           SILC_NOTIFY_TYPE_UMODE_CHANGE, 2,
1317                           idp->data, idp->len,
1318                           mode, 4);
1319   silc_buffer_free(idp);
1320 }
1321
1322 /* Sends BAN notify type. This tells that ban has been either `add'ed
1323    or `del'eted on the `channel. This function is used to send the packet
1324    between routers as broadcast packet. */
1325
1326 void silc_server_send_notify_ban(SilcServer server,
1327                                  SilcSocketConnection sock,
1328                                  bool broadcast,
1329                                  SilcChannelEntry channel,
1330                                  char *add, char *del)
1331 {
1332   SilcBuffer idp;
1333
1334   idp = silc_id_payload_encode((void *)channel->id, SILC_ID_CHANNEL);
1335   silc_server_send_notify(server, sock, broadcast,
1336                           SILC_NOTIFY_TYPE_BAN, 3,
1337                           idp->data, idp->len,
1338                           add, add ? strlen(add) : 0,
1339                           del, del ? strlen(del) : 0);
1340   silc_buffer_free(idp);
1341 }
1342
1343 /* Sends INVITE notify type. This tells that invite has been either `add'ed
1344    or `del'eted on the `channel.  The sender of the invite is the `client_id'.
1345    This function is used to send the packet between routers as broadcast
1346    packet. */
1347
1348 void silc_server_send_notify_invite(SilcServer server,
1349                                     SilcSocketConnection sock,
1350                                     bool broadcast,
1351                                     SilcChannelEntry channel,
1352                                     SilcClientID *client_id,
1353                                     char *add, char *del)
1354 {
1355   SilcBuffer idp, idp2;
1356
1357   idp = silc_id_payload_encode((void *)channel->id, SILC_ID_CHANNEL);
1358   idp2 = silc_id_payload_encode((void *)client_id, SILC_ID_CLIENT);
1359   silc_server_send_notify(server, sock, broadcast,
1360                           SILC_NOTIFY_TYPE_INVITE, 5,
1361                           idp->data, idp->len,
1362                           channel->channel_name, strlen(channel->channel_name),
1363                           idp2->data, idp2->len,
1364                           add, add ? strlen(add) : 0,
1365                           del, del ? strlen(del) : 0);
1366   silc_buffer_free(idp);
1367   silc_buffer_free(idp2);
1368 }
1369
1370 /* Sends notify message destined to specific entity. */
1371
1372 void silc_server_send_notify_dest(SilcServer server,
1373                                   SilcSocketConnection sock,
1374                                   bool broadcast,
1375                                   void *dest_id,
1376                                   SilcIdType dest_id_type,
1377                                   SilcNotifyType type,
1378                                   SilcUInt32 argc, ...)
1379 {
1380   va_list ap;
1381   SilcBuffer packet;
1382
1383   va_start(ap, argc);
1384
1385   packet = silc_notify_payload_encode(type, argc, ap);
1386   silc_server_packet_send_dest(server, sock, SILC_PACKET_NOTIFY,
1387                                broadcast ? SILC_PACKET_FLAG_BROADCAST : 0,
1388                                dest_id, dest_id_type,
1389                                packet->data, packet->len, FALSE);
1390   silc_buffer_free(packet);
1391   va_end(ap);
1392 }
1393
1394 /* Sends notify message to a channel. The notify message sent is
1395    distributed to all clients on the channel. If `route_notify' is TRUE
1396    then the notify may be routed to primary route or to some other routers.
1397    If FALSE it is assured that the notify is sent only locally. If `sender'
1398    is provided then the packet is not sent to that connection since it
1399    originally came from it. */
1400
1401 void silc_server_send_notify_to_channel(SilcServer server,
1402                                         SilcSocketConnection sender,
1403                                         SilcChannelEntry channel,
1404                                         bool route_notify,
1405                                         SilcNotifyType type,
1406                                         SilcUInt32 argc, ...)
1407 {
1408   va_list ap;
1409   SilcBuffer packet;
1410
1411   va_start(ap, argc);
1412
1413   packet = silc_notify_payload_encode(type, argc, ap);
1414   silc_server_packet_send_to_channel(server, sender, channel,
1415                                      SILC_PACKET_NOTIFY, route_notify,
1416                                      packet->data, packet->len, FALSE);
1417   silc_buffer_free(packet);
1418   va_end(ap);
1419 }
1420
1421 /* Send notify message to all channels the client has joined. It is quaranteed
1422    that the message is sent only once to a client (ie. if a client is joined
1423    on two same channel it will receive only one notify message). Also, this
1424    sends only to local clients (locally connected if we are server, and to
1425    local servers if we are router). If `sender' is provided the packet is
1426    not sent to that client at all. */
1427
1428 void silc_server_send_notify_on_channels(SilcServer server,
1429                                          SilcClientEntry sender,
1430                                          SilcClientEntry client,
1431                                          SilcNotifyType type,
1432                                          SilcUInt32 argc, ...)
1433 {
1434   int k;
1435   SilcSocketConnection sock = NULL;
1436   SilcPacketContext packetdata;
1437   SilcClientEntry c;
1438   SilcClientEntry *sent_clients = NULL;
1439   SilcUInt32 sent_clients_count = 0;
1440   SilcServerEntry *routed = NULL;
1441   SilcUInt32 routed_count = 0;
1442   SilcHashTableList htl, htl2;
1443   SilcChannelEntry channel;
1444   SilcChannelClientEntry chl, chl2;
1445   SilcIDListData idata;
1446   SilcBuffer packet;
1447   unsigned char *data;
1448   SilcUInt32 data_len;
1449   bool force_send = FALSE;
1450   va_list ap;
1451
1452   SILC_LOG_DEBUG(("Start"));
1453
1454   if (!silc_hash_table_count(client->channels))
1455     return;
1456
1457   va_start(ap, argc);
1458   packet = silc_notify_payload_encode(type, argc, ap);
1459   data = packet->data;
1460   data_len = packet->len;
1461
1462   /* Set the packet context pointers. */
1463   packetdata.flags = 0;
1464   packetdata.type = SILC_PACKET_NOTIFY;
1465   packetdata.src_id = silc_id_id2str(server->id, SILC_ID_SERVER);
1466   packetdata.src_id_len = silc_id_get_len(server->id, SILC_ID_SERVER);
1467   packetdata.src_id_type = SILC_ID_SERVER;
1468
1469   silc_hash_table_list(client->channels, &htl);
1470   while (silc_hash_table_get(&htl, NULL, (void *)&chl)) {
1471     channel = chl->channel;
1472
1473     /* Send the message to all clients on the channel's client list. */
1474     silc_hash_table_list(channel->user_list, &htl2);
1475     while (silc_hash_table_get(&htl2, NULL, (void *)&chl2)) {
1476       c = chl2->client;
1477
1478       if (sender && c == sender)
1479         continue;
1480
1481       /* Check if we have sent the packet to this client already */
1482       for (k = 0; k < sent_clients_count; k++)
1483         if (sent_clients[k] == c)
1484           break;
1485       if (k < sent_clients_count)
1486         continue;
1487
1488       /* If we are router and if this client has router set it is not
1489          locally connected client and we will route the message to the
1490          router set in the client. */
1491       if (c && c->router && server->server_type == SILC_ROUTER) {
1492         /* Check if we have sent the packet to this route already */
1493         for (k = 0; k < routed_count; k++)
1494           if (routed[k] == c->router)
1495             break;
1496         if (k < routed_count)
1497           continue;
1498
1499         /* Get data used in packet header encryption, keys and stuff. */
1500         sock = (SilcSocketConnection)c->router->connection;
1501         idata = (SilcIDListData)c->router;
1502
1503         {
1504           SILC_LOG_DEBUG(("*****************"));
1505           SILC_LOG_DEBUG(("client->router->id %s",
1506                           silc_id_render(c->router->id, SILC_ID_SERVER)));
1507           SILC_LOG_DEBUG(("client->router->connection->user_data->id %s",
1508                           silc_id_render(((SilcServerEntry)sock->user_data)->id, SILC_ID_SERVER)));
1509         }
1510
1511         packetdata.dst_id = silc_id_id2str(c->router->id, SILC_ID_SERVER);
1512         packetdata.dst_id_len = silc_id_get_len(c->router->id, SILC_ID_SERVER);
1513         packetdata.dst_id_type = SILC_ID_SERVER;
1514
1515         /* Send the packet */
1516         silc_server_packet_send_to_channel_real(server, sock, &packetdata,
1517                                                 idata->send_key,
1518                                                 idata->hmac_send,
1519                                                 idata->psn_send++,
1520                                                 data, data_len, FALSE,
1521                                                 force_send);
1522
1523         silc_free(packetdata.dst_id);
1524
1525         /* We want to make sure that the packet is routed to same router
1526            only once. Mark this route as sent route. */
1527         routed = silc_realloc(routed, sizeof(*routed) * (routed_count + 1));
1528         routed[routed_count++] = c->router;
1529         continue;
1530       }
1531
1532       if (c && c->router)
1533         continue;
1534
1535       /* Send to locally connected client */
1536       if (c) {
1537
1538         /* Get data used in packet header encryption, keys and stuff. */
1539         sock = (SilcSocketConnection)c->connection;
1540         idata = (SilcIDListData)c;
1541
1542         if (!sock)
1543           continue;
1544
1545         packetdata.dst_id = silc_id_id2str(c->id, SILC_ID_CLIENT);
1546         packetdata.dst_id_len = silc_id_get_len(c->id, SILC_ID_CLIENT);
1547         packetdata.dst_id_type = SILC_ID_CLIENT;
1548
1549         /* Send the packet */
1550         silc_server_packet_send_to_channel_real(server, sock, &packetdata,
1551                                                 idata->send_key,
1552                                                 idata->hmac_send,
1553                                                 idata->psn_send++,
1554                                                 data, data_len, FALSE,
1555                                                 force_send);
1556
1557         silc_free(packetdata.dst_id);
1558
1559         /* Make sure that we send the notify only once per client. */
1560         sent_clients = silc_realloc(sent_clients, sizeof(*sent_clients) *
1561                                     (sent_clients_count + 1));
1562         sent_clients[sent_clients_count++] = c;
1563       }
1564     }
1565     silc_hash_table_list_reset(&htl2);
1566   }
1567
1568   silc_hash_table_list_reset(&htl);
1569   silc_free(routed);
1570   silc_free(sent_clients);
1571   silc_free(packetdata.src_id);
1572   silc_buffer_free(packet);
1573   va_end(ap);
1574 }
1575
1576 /* Sends New ID Payload to remote end. The packet is used to distribute
1577    information about new registered clients, servers, channel etc. usually
1578    to routers so that they can keep these information up to date.
1579    If the argument `broadcast' is TRUE then the packet is sent as
1580    broadcast packet. */
1581
1582 void silc_server_send_new_id(SilcServer server,
1583                              SilcSocketConnection sock,
1584                              bool broadcast,
1585                              void *id, SilcIdType id_type,
1586                              SilcUInt32 id_len)
1587 {
1588   SilcBuffer idp;
1589
1590   SILC_LOG_DEBUG(("Start"));
1591
1592   idp = silc_id_payload_encode(id, id_type);
1593   silc_server_packet_send(server, sock, SILC_PACKET_NEW_ID,
1594                           broadcast ? SILC_PACKET_FLAG_BROADCAST : 0,
1595                           idp->data, idp->len, FALSE);
1596
1597   /* Send to backup routers if this is being broadcasted to primary
1598      router. */
1599   if (server->router && server->router->connection &&
1600       sock == server->router->connection && broadcast)
1601     silc_server_backup_send(server, NULL, SILC_PACKET_NEW_ID, 0,
1602                             idp->data, idp->len, FALSE, TRUE);
1603
1604   silc_buffer_free(idp);
1605 }
1606
1607 /* Send New Channel Payload to notify about newly created channel in the
1608    SILC network. Router uses this to notify other routers in the network
1609    about new channel. This packet is broadcasted by router. */
1610
1611 void silc_server_send_new_channel(SilcServer server,
1612                                   SilcSocketConnection sock,
1613                                   bool broadcast,
1614                                   char *channel_name,
1615                                   void *channel_id,
1616                                   SilcUInt32 channel_id_len,
1617                                   SilcUInt32 mode)
1618 {
1619   SilcBuffer packet;
1620   unsigned char *cid;
1621   SilcUInt32 name_len = strlen(channel_name);
1622
1623   SILC_LOG_DEBUG(("Start"));
1624
1625   cid = silc_id_id2str(channel_id, SILC_ID_CHANNEL);
1626   if (!cid)
1627     return;
1628
1629   /* Encode the channel payload */
1630   packet = silc_channel_payload_encode(channel_name, name_len,
1631                                        cid, channel_id_len, mode);
1632
1633   silc_server_packet_send(server, sock, SILC_PACKET_NEW_CHANNEL,
1634                           broadcast ? SILC_PACKET_FLAG_BROADCAST : 0,
1635                           packet->data, packet->len, FALSE);
1636
1637   /* Send to backup routers if this is being broadcasted to primary
1638      router. */
1639   if (server->server_type == SILC_ROUTER &&
1640       server->router && server->router->connection &&
1641       sock == server->router->connection && broadcast)
1642     silc_server_backup_send(server, NULL, SILC_PACKET_NEW_CHANNEL, 0,
1643                             packet->data, packet->len, FALSE, TRUE);
1644
1645   silc_free(cid);
1646   silc_buffer_free(packet);
1647 }
1648
1649 /* Send Channel Key payload to distribute the new channel key. Normal server
1650    sends this to router when new client joins to existing channel. Router
1651    sends this to the local server who sent the join command in case where
1652    the channel did not exist yet. Both normal and router servers uses this
1653    also to send this to locally connected clients on the channel. This
1654    must not be broadcasted packet. Routers do not send this to each other.
1655    If `sender is provided then the packet is not sent to that connection since
1656    it originally came from it. */
1657
1658 void silc_server_send_channel_key(SilcServer server,
1659                                   SilcSocketConnection sender,
1660                                   SilcChannelEntry channel,
1661                                   unsigned char route)
1662 {
1663   SilcBuffer packet;
1664   unsigned char *chid;
1665   SilcUInt32 tmp_len;
1666
1667   SILC_LOG_DEBUG(("Sending key to channel %s", channel->channel_name));
1668
1669   chid = silc_id_id2str(channel->id, SILC_ID_CHANNEL);
1670   if (!chid)
1671     return;
1672
1673   /* Encode channel key packet */
1674   tmp_len = strlen(channel->channel_key->cipher->name);
1675   packet = silc_channel_key_payload_encode(silc_id_get_len(channel->id,
1676                                                            SILC_ID_CHANNEL),
1677                                            chid, tmp_len,
1678                                            channel->channel_key->cipher->name,
1679                                            channel->key_len / 8, channel->key);
1680   silc_server_packet_send_to_channel(server, sender, channel,
1681                                      SILC_PACKET_CHANNEL_KEY,
1682                                      route, packet->data, packet->len,
1683                                      FALSE);
1684   silc_buffer_free(packet);
1685   silc_free(chid);
1686 }
1687
1688 /* Generic function to send any command. The arguments must be sent already
1689    encoded into correct form in correct order. */
1690
1691 void silc_server_send_command(SilcServer server,
1692                               SilcSocketConnection sock,
1693                               SilcCommand command,
1694                               SilcUInt16 ident,
1695                               SilcUInt32 argc, ...)
1696 {
1697   SilcBuffer packet;
1698   va_list ap;
1699
1700   va_start(ap, argc);
1701
1702   packet = silc_command_payload_encode_vap(command, ident, argc, ap);
1703   silc_server_packet_send(server, sock, SILC_PACKET_COMMAND, 0,
1704                           packet->data, packet->len, TRUE);
1705   silc_buffer_free(packet);
1706   va_end(ap);
1707 }
1708
1709 /* Generic function to send any command reply. The arguments must be sent
1710    already encoded into correct form in correct order. */
1711
1712 void silc_server_send_command_reply(SilcServer server,
1713                                     SilcSocketConnection sock,
1714                                     SilcCommand command,
1715                                     SilcCommandStatus status,
1716                                     SilcUInt16 ident,
1717                                     SilcUInt32 argc, ...)
1718 {
1719   SilcBuffer packet;
1720   va_list ap;
1721
1722   va_start(ap, argc);
1723
1724   packet = silc_command_reply_payload_encode_vap(command, status, ident,
1725                                                  argc, ap);
1726   silc_server_packet_send(server, sock, SILC_PACKET_COMMAND_REPLY, 0,
1727                           packet->data, packet->len, TRUE);
1728   silc_buffer_free(packet);
1729   va_end(ap);
1730 }
1731
1732 /* Generic function to send any command reply. The arguments must be sent
1733    already encoded into correct form in correct order. */
1734
1735 void silc_server_send_dest_command_reply(SilcServer server,
1736                                          SilcSocketConnection sock,
1737                                          void *dst_id,
1738                                          SilcIdType dst_id_type,
1739                                          SilcCommand command,
1740                                          SilcCommandStatus status,
1741                                          SilcUInt16 ident,
1742                                          SilcUInt32 argc, ...)
1743 {
1744   SilcBuffer packet;
1745   va_list ap;
1746
1747   va_start(ap, argc);
1748
1749   packet = silc_command_reply_payload_encode_vap(command, status, ident,
1750                                                  argc, ap);
1751   silc_server_packet_send_dest(server, sock, SILC_PACKET_COMMAND_REPLY, 0,
1752                                dst_id, dst_id_type, packet->data,
1753                                packet->len, TRUE);
1754   silc_buffer_free(packet);
1755   va_end(ap);
1756 }
1757
1758 /* Send the heartbeat packet. */
1759
1760 void silc_server_send_heartbeat(SilcServer server,
1761                                 SilcSocketConnection sock)
1762 {
1763   silc_server_packet_send(server, sock, SILC_PACKET_HEARTBEAT, 0,
1764                           NULL, 0, FALSE);
1765 }
1766
1767 /* Generic function to relay packet we've received. This is used to relay
1768    packets to a client but generally can be used to other purposes as well. */
1769
1770 void silc_server_relay_packet(SilcServer server,
1771                               SilcSocketConnection dst_sock,
1772                               SilcCipher cipher,
1773                               SilcHmac hmac,
1774                               SilcUInt32 sequence,
1775                               SilcPacketContext *packet,
1776                               bool force_send)
1777 {
1778   const SilcBufferStruct p;
1779
1780   silc_buffer_push(packet->buffer, SILC_PACKET_HEADER_LEN + packet->src_id_len
1781                    + packet->dst_id_len + packet->padlen);
1782   if (!silc_packet_send_prepare(dst_sock, 0, 0, packet->buffer->len, hmac,
1783                                 (const SilcBuffer)&p)) {
1784     SILC_LOG_ERROR(("Cannot send packet"));
1785     return;
1786   }
1787   silc_buffer_put((SilcBuffer)&p, packet->buffer->data, packet->buffer->len);
1788
1789   /* Re-encrypt packet */
1790   silc_packet_encrypt(cipher, hmac, sequence, (SilcBuffer)&p, p.len);
1791
1792   /* Send the packet */
1793   silc_server_packet_send_real(server, dst_sock, force_send);
1794
1795   silc_buffer_pull(packet->buffer, SILC_PACKET_HEADER_LEN + packet->src_id_len
1796                    + packet->dst_id_len + packet->padlen);
1797 }
1798
1799 /* Routine used to send the connection authentication packet. */
1800
1801 void silc_server_send_connection_auth_request(SilcServer server,
1802                                               SilcSocketConnection sock,
1803                                               SilcUInt16 conn_type,
1804                                               SilcAuthMethod auth_meth)
1805 {
1806   SilcBuffer packet;
1807
1808   packet = silc_buffer_alloc(4);
1809   silc_buffer_pull_tail(packet, SILC_BUFFER_END(packet));
1810   silc_buffer_format(packet,
1811                      SILC_STR_UI_SHORT(conn_type),
1812                      SILC_STR_UI_SHORT(auth_meth),
1813                      SILC_STR_END);
1814
1815   silc_server_packet_send(server, sock, SILC_PACKET_CONNECTION_AUTH_REQUEST,
1816                           0, packet->data, packet->len, FALSE);
1817   silc_buffer_free(packet);
1818 }
1819
1820 /* Purge the outgoing packet queue to the network if there is data. This
1821    function can be used to empty the packet queue. It is guaranteed that
1822    after this function returns the outgoing data queue is empty. */
1823
1824 void silc_server_packet_queue_purge(SilcServer server,
1825                                     SilcSocketConnection sock)
1826 {
1827   if (sock && SILC_IS_OUTBUF_PENDING(sock) &&
1828       (SILC_IS_DISCONNECTED(sock) == FALSE)) {
1829     server->stat.packets_sent++;
1830     silc_packet_send(sock, TRUE);
1831     SILC_SET_CONNECTION_FOR_INPUT(server->schedule, sock->sock);
1832     SILC_UNSET_OUTBUF_PENDING(sock);
1833     silc_buffer_clear(sock->outbuf);
1834   }
1835 }