src/socket.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 /* $Core: libIRCDsocket */
  15
  16 #include "inspircd.h"
  17 #include "socket.h"
  18 #include "socketengine.h"
  19 #include "wildcard.h"
  20
  21 using namespace irc::sockets;
  22
  23 /* Used when comparing CIDR masks for the modulus bits left over.
  24  * A lot of ircd's seem to do this:
  25  * ((-1) << (8 - (mask % 8)))
  26  * But imho, it sucks in comparison to a nice neat lookup table.
  27  */
  28 const unsigned char inverted_bits[8] = {        0x00, /* 00000000 - 0 bits - never actually used */
  29                                 0x80, /* 10000000 - 1 bits */
  30                                 0xC0, /* 11000000 - 2 bits */
  31                                 0xE0, /* 11100000 - 3 bits */
  32                                 0xF0, /* 11110000 - 4 bits */
  33                                 0xF8, /* 11111000 - 5 bits */
  34                                 0xFC, /* 11111100 - 6 bits */
  35                                 0xFE  /* 11111110 - 7 bits */
  36 };
  37
  38
  39 ListenSocket::ListenSocket(InspIRCd* Instance, int port, char* addr) : ServerInstance(Instance), desc("plaintext"), bind_addr(addr), bind_port(port)
  40 {
  41         this->SetFd(OpenTCPSocket(addr));
  42         if (this->GetFd() > -1)
  43         {
  44                 if (!Instance->BindSocket(this->fd,port,addr))
  45                         this->fd = -1;
  46 #ifdef IPV6
  47                 if ((!*addr) || (strchr(addr,':')))
  48                         this->family = AF_INET6;
  49                 else
  50 #endif
  51                 this->family = AF_INET;
  52                 Instance->SE->AddFd(this);
  53         }
  54 }
  55
  56 ListenSocket::~ListenSocket()
  57 {
  58         if (this->GetFd() > -1)
  59         {
  60                 ServerInstance->SE->DelFd(this);
  61                 ServerInstance->Logs->Log("SOCKET", DEBUG,"Shut down listener on fd %d", this->fd);
  62                 if (ServerInstance->SE->Shutdown(this, 2) || ServerInstance->SE->Close(this))
  63                         ServerInstance->Logs->Log("SOCKET", DEBUG,"Failed to cancel listener: %s", strerror(errno));
  64                 this->fd = -1;
  65         }
  66 }
  67
  68
  69 // XXX this is a bit of an untidy way to avoid reallocating this constantly. also, we leak it on shutdown.. but that's kinda minor - w
  70 static sockaddr *sock_us;
  71 static sockaddr *client;
  72 static bool setup_sock = false;
  73
  74 void ListenSocket::HandleEvent(EventType, int)
  75 {
  76         socklen_t uslen, length;                // length of our port number
  77         int incomingSockfd, in_port;
  78
  79         if (!setup_sock)
  80         {
  81                 sock_us = new sockaddr[2];
  82                 client = new sockaddr[2];
  83                 setup_sock = true;
  84         }
  85
  86 #ifdef IPV6
  87         if (this->family == AF_INET6)
  88         {
  89                 uslen = sizeof(sockaddr_in6);
  90                 length = sizeof(sockaddr_in6);
  91         }
  92         else
  93 #endif
  94         {
  95                 uslen = sizeof(sockaddr_in);
  96                 length = sizeof(sockaddr_in);
  97         }
  98
  99         incomingSockfd = ServerInstance->SE->Accept(this, (sockaddr*)client, &length);
 100
 101         if ((incomingSockfd > -1) && (!ServerInstance->SE->GetSockName(this, sock_us, &uslen)))
 102         {
 103                 char buf[MAXBUF];
 104 #ifdef IPV6
 105                 if (this->family == AF_INET6)
 106                 {
 107                         inet_ntop(AF_INET6, &((const sockaddr_in6*)client)->sin6_addr, buf, sizeof(buf));
 108                         in_port = ntohs(((sockaddr_in6*)sock_us)->sin6_port);
 109                 }
 110                 else
 111 #endif
 112                 {
 113                         inet_ntop(AF_INET, &((const sockaddr_in*)client)->sin_addr, buf, sizeof(buf));
 114                         in_port = ntohs(((sockaddr_in*)sock_us)->sin_port);
 115                 }
 116
 117                 ServerInstance->SE->NonBlocking(incomingSockfd);
 118
 119                 if (ServerInstance->Config->GetIOHook(in_port))
 120                 {
 121                         try
 122                         {
 123                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, buf, in_port);
 124                         }
 125                         catch (CoreException& modexcept)
 126                         {
 127                                 ServerInstance->Logs->Log("SOCKET", DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 128                         }
 129                 }
 130                 ServerInstance->stats->statsAccept++;
 131                 ServerInstance->Users->AddClient(ServerInstance, incomingSockfd, in_port, false, this->family, client);
 132         }
 133         else
 134         {
 135                 ServerInstance->SE->Shutdown(incomingSockfd, 2);
 136                 ServerInstance->SE->Close(incomingSockfd);
 137                 ServerInstance->stats->statsRefused++;
 138         }
 139 }
 140
 141 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
 142 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
 143 {
 144         unsigned int divisor = mask_bits / 8; /* Number of whole bytes in the mask */
 145         unsigned int modulus = mask_bits % 8; /* Remaining bits in the mask after whole bytes are dealt with */
 146
 147         /* First (this is faster) compare the odd bits with logic ops */
 148         if (modulus)
 149                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
 150                         /* If they dont match, return false */
 151                         return false;
 152
 153         /* Secondly (this is slower) compare the whole bytes */
 154         if (memcmp(address, mask, divisor))
 155                 return false;
 156
 157         /* The address matches the mask, to mask_bits bits of mask */
 158         return true;
 159 }
 160
 161 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
 162 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
 163 {
 164         return MatchCIDR(address, cidr_mask, false);
 165 }
 166
 167 /* Match CIDR strings, e.g. 127.0.0.1 to 127.0.0.0/8 or 3ffe:1:5:6::8 to 3ffe:1::0/32
 168  * If you have a lot of hosts to match, youre probably better off building your mask once
 169  * and then using the lower level MatchCIDRBits directly.
 170  *
 171  * This will also attempt to match any leading usernames or nicknames on the mask, using
 172  * match(), when match_with_username is true.
 173  */
 174 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
 175 {
 176         unsigned char addr_raw[16];
 177         unsigned char mask_raw[16];
 178         unsigned int bits = 0;
 179         char* mask = NULL;
 180
 181         /* The caller is trying to match ident@<mask>/bits.
 182          * Chop off the ident@ portion, use match() on it
 183          * seperately.
 184          */
 185         if (match_with_username)
 186         {
 187                 /* Duplicate the strings, and try to find the position
 188                  * of the @ symbol in each */
 189                 char* address_dupe = strdup(address);
 190                 char* cidr_dupe = strdup(cidr_mask);
 191
 192                 /* Use strchr not strrchr, because its going to be nearer to the left */
 193                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 194                 char* username_addr_pos = strrchr(address_dupe, '@');
 195
 196                 /* Both strings have an @ symbol in them */
 197                 if (username_mask_pos && username_addr_pos)
 198                 {
 199                         /* Zero out the location of the @ symbol */
 200                         *username_mask_pos = *username_addr_pos = 0;
 201
 202                         /* Try and match() the strings before the @
 203                          * symbols, and recursively call MatchCIDR without
 204                          * username matching enabled to match the host part.
 205                          */
 206                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 207
 208                         /* Free the stuff we created */
 209                         free(address_dupe);
 210                         free(cidr_dupe);
 211
 212                         /* Return a result */
 213                         return result;
 214                 }
 215                 else
 216                 {
 217                         /* One or both didnt have an @ in,
 218                          * just match as CIDR
 219                          */
 220                         free(address_dupe);
 221                         free(cidr_dupe);
 222                         mask = strdup(cidr_mask);
 223                 }
 224         }
 225         else
 226         {
 227                 /* Make a copy of the cidr mask string,
 228                  * we're going to change it
 229                  */
 230                 mask = strdup(cidr_mask);
 231         }
 232
 233         in_addr  address_in4;
 234         in_addr  mask_in4;
 235
 236
 237         /* Use strrchr for this, its nearer to the right */
 238         char* bits_chars = strrchr(mask,'/');
 239
 240         if (bits_chars)
 241         {
 242                 bits = atoi(bits_chars + 1);
 243                 *bits_chars = 0;
 244         }
 245         else
 246         {
 247                 /* No 'number of bits' field! */
 248                 free(mask);
 249                 return false;
 250         }
 251
 252 #ifdef SUPPORT_IP6LINKS
 253         in6_addr address_in6;
 254         in6_addr mask_in6;
 255
 256         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 257         {
 258                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 259                 {
 260                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 261                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 262
 263                         if (bits > 128)
 264                                 bits = 128;
 265                 }
 266                 else
 267                 {
 268                         /* The address was valid ipv6, but the mask
 269                          * that goes with it wasnt.
 270                          */
 271                         free(mask);
 272                         return false;
 273                 }
 274         }
 275         else
 276 #endif
 277         if (inet_pton(AF_INET, address, &address_in4) > 0)
 278         {
 279                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 280                 {
 281                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 282                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 283
 284                         if (bits > 32)
 285                                 bits = 32;
 286                 }
 287                 else
 288                 {
 289                         /* The address was valid ipv4,
 290                          * but the mask that went with it wasnt.
 291                          */
 292                         free(mask);
 293                         return false;
 294                 }
 295         }
 296         else
 297         {
 298                 /* The address was neither ipv4 or ipv6 */
 299                 free(mask);
 300                 return false;
 301         }
 302
 303         /* Low-level-match the bits in the raw data */
 304         free(mask);
 305         return MatchCIDRBits(addr_raw, mask_raw, bits);
 306 }
 307
 308 /** This will bind a socket to a port. It works for UDP/TCP.
 309  * It can only bind to IP addresses, if you wish to bind to hostnames
 310  * you should first resolve them using class 'Resolver'.
 311  */
 312 bool InspIRCd::BindSocket(int sockfd, int port, const char* addr, bool dolisten)
 313 {
 314         /* We allocate 2 of these, because sockaddr_in6 is larger than sockaddr (ugh, hax) */
 315         sockaddr* servaddr = new sockaddr[2];
 316         memset(servaddr,0,sizeof(sockaddr)*2);
 317
 318         int ret, size;
 319
 320         if (*addr == '*')
 321                 addr = "";
 322
 323 #ifdef IPV6
 324         if (*addr)
 325         {
 326                 /* There is an address here. Is it ipv6? */
 327                 if (strchr(addr,':'))
 328                 {
 329                         /* Yes it is */
 330                         in6_addr addy;
 331                         if (inet_pton(AF_INET6, addr, &addy) < 1)
 332                         {
 333                                 delete[] servaddr;
 334                                 return false;
 335                         }
 336
 337                         ((sockaddr_in6*)servaddr)->sin6_family = AF_INET6;
 338                         memcpy(&(((sockaddr_in6*)servaddr)->sin6_addr), &addy, sizeof(in6_addr));
 339                         ((sockaddr_in6*)servaddr)->sin6_port = htons(port);
 340                         size = sizeof(sockaddr_in6);
 341                 }
 342                 else
 343                 {
 344                         /* No, its not */
 345                         in_addr addy;
 346                         if (inet_pton(AF_INET, addr, &addy) < 1)
 347                         {
 348                                 delete[] servaddr;
 349                                 return false;
 350                         }
 351
 352                         ((sockaddr_in*)servaddr)->sin_family = AF_INET;
 353                         ((sockaddr_in*)servaddr)->sin_addr = addy;
 354                         ((sockaddr_in*)servaddr)->sin_port = htons(port);
 355                         size = sizeof(sockaddr_in);
 356                 }
 357         }
 358         else
 359         {
 360                 if (port == -1)
 361                 {
 362                         /* Port -1: Means UDP IPV4 port binding - Special case
 363                          * used by DNS engine.
 364                          */
 365                         ((sockaddr_in*)servaddr)->sin_family = AF_INET;
 366                         ((sockaddr_in*)servaddr)->sin_addr.s_addr = htonl(INADDR_ANY);
 367                         ((sockaddr_in*)servaddr)->sin_port = 0;
 368                         size = sizeof(sockaddr_in);
 369                 }
 370                 else
 371                 {
 372                         /* Theres no address here, default to ipv6 bind to all */
 373                         ((sockaddr_in6*)servaddr)->sin6_family = AF_INET6;
 374                         memset(&(((sockaddr_in6*)servaddr)->sin6_addr), 0, sizeof(in6_addr));
 375                         ((sockaddr_in6*)servaddr)->sin6_port = htons(port);
 376                         size = sizeof(sockaddr_in6);
 377                 }
 378         }
 379 #else
 380         /* If we aren't built with ipv6, the choice becomes simple */
 381         ((sockaddr_in*)servaddr)->sin_family = AF_INET;
 382         if (*addr)
 383         {
 384                 /* There is an address here. */
 385                 in_addr addy;
 386                 if (inet_pton(AF_INET, addr, &addy) < 1)
 387                 {
 388                         delete[] servaddr;
 389                         return false;
 390                 }
 391                 ((sockaddr_in*)servaddr)->sin_addr = addy;
 392         }
 393         else
 394         {
 395                 /* Bind ipv4 to all */
 396                 ((sockaddr_in*)servaddr)->sin_addr.s_addr = htonl(INADDR_ANY);
 397         }
 398         /* Bind ipv4 port number */
 399         ((sockaddr_in*)servaddr)->sin_port = htons(port);
 400         size = sizeof(sockaddr_in);
 401 #endif
 402         ret = SE->Bind(sockfd, servaddr, size);
 403         delete[] servaddr;
 404
 405         if (ret < 0)
 406         {
 407                 return false;
 408         }
 409         else
 410         {
 411                 if (dolisten)
 412                 {
 413                         if (SE->Listen(sockfd, Config->MaxConn) == -1)
 414                         {
 415                                 this->Logs->Log("SOCKET",DEFAULT,"ERROR in listen(): %s",strerror(errno));
 416                                 return false;
 417                         }
 418                         else
 419                         {
 420                                 this->Logs->Log("SOCKET",DEBUG,"New socket binding for %d with listen: %s:%d", sockfd, addr, port);
 421                                 SE->NonBlocking(sockfd);
 422                                 return true;
 423                         }
 424                 }
 425                 else
 426                 {
 427                         this->Logs->Log("SOCKET",DEBUG,"New socket binding for %d without listen: %s:%d", sockfd, addr, port);
 428                         return true;
 429                 }
 430         }
 431 }
 432
 433 // Open a TCP Socket
 434 int irc::sockets::OpenTCPSocket(char* addr, int socktype)
 435 {
 436         int sockfd;
 437         int on = 1;
 438         addr = addr;
 439         struct linger linger = { 0, 0 };
 440 #ifdef IPV6
 441         if (strchr(addr,':') || (!*addr))
 442                 sockfd = socket (PF_INET6, socktype, 0);
 443         else
 444                 sockfd = socket (PF_INET, socktype, 0);
 445         if (sockfd < 0)
 446 #else
 447         if ((sockfd = socket (PF_INET, socktype, 0)) < 0)
 448 #endif
 449         {
 450                 return ERROR;
 451         }
 452         else
 453         {
 454                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (char*)&on, sizeof(on));
 455                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 456                 linger.l_onoff = 1;
 457                 linger.l_linger = 1;
 458                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, (char*)&linger,sizeof(linger));
 459                 return (sockfd);
 460         }
 461 }
 462
 463 int InspIRCd::BindPorts(bool, int &ports_found, FailedPortList &failed_ports)
 464 {
 465         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 466         int bound = 0;
 467         bool started_with_nothing = (Config->ports.size() == 0);
 468         std::vector<std::pair<std::string, int> > old_ports;
 469
 470         /* XXX: Make a copy of the old ip/port pairs here */
 471         for (std::vector<ListenSocket*>::iterator o = Config->ports.begin(); o != Config->ports.end(); ++o)
 472                 old_ports.push_back(make_pair((*o)->GetIP(), (*o)->GetPort()));
 473
 474         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 475         {
 476                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 477                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 478                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 479
 480                 if (strncmp(Addr, "::ffff:", 7) == 0)
 481                         this->Logs->Log("SOCKET",DEFAULT, "Using 4in6 (::ffff:) isn't recommended. You should bind IPv4 addresses directly instead.");
 482
 483                 if ((!*Type) || (!strcmp(Type,"clients")))
 484                 {
 485                         irc::portparser portrange(configToken, false);
 486                         int portno = -1;
 487                         while ((portno = portrange.GetToken()))
 488                         {
 489                                 if (*Addr == '*')
 490                                         *Addr = 0;
 491
 492                                 bool skip = false;
 493                                 for (std::vector<ListenSocket*>::iterator n = Config->ports.begin(); n != Config->ports.end(); ++n)
 494                                 {
 495                                         if (((*n)->GetIP() == Addr) && ((*n)->GetPort() == portno))
 496                                         {
 497                                                 skip = true;
 498                                                 /* XXX: Here, erase from our copy of the list */
 499                                                 for (std::vector<std::pair<std::string, int> >::iterator k = old_ports.begin(); k != old_ports.end(); ++k)
 500                                                 {
 501                                                         if ((k->first == Addr) && (k->second == portno))
 502                                                         {
 503                                                                 old_ports.erase(k);
 504                                                                 break;
 505                                                         }
 506                                                 }
 507                                         }
 508                                 }
 509                                 if (!skip)
 510                                 {
 511                                         ListenSocket* ll = new ListenSocket(this, portno, Addr);
 512                                         if (ll->GetFd() > -1)
 513                                         {
 514                                                 bound++;
 515                                                 Config->ports.push_back(ll);
 516                                         }
 517                                         else
 518                                         {
 519                                                 failed_ports.push_back(std::make_pair(Addr, portno));
 520                                         }
 521                                         ports_found++;
 522                                 }
 523                         }
 524                 }
 525         }
 526
 527         /* XXX: Here, anything left in our copy list, close as removed */
 528         if (!started_with_nothing)
 529         {
 530                 for (size_t k = 0; k < old_ports.size(); ++k)
 531                 {
 532                         for (std::vector<ListenSocket*>::iterator n = Config->ports.begin(); n != Config->ports.end(); ++n)
 533                         {
 534                                 if (((*n)->GetIP() == old_ports[k].first) && ((*n)->GetPort() == old_ports[k].second))
 535                                 {
 536                                         this->Logs->Log("SOCKET",DEFAULT,"Port binding %s:%d was removed from the config file, closing.", old_ports[k].first.c_str(), old_ports[k].second);
 537                                         delete *n;
 538                                         Config->ports.erase(n);
 539                                         break;
 540                                 }
 541                         }
 542                 }
 543         }
 544
 545         return bound;
 546 }
 547
 548 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 549 {
 550         static char buf[1024];
 551         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 552         return buf;
 553 }
 554
 555 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 556 {
 557         return inet_pton(AF_FAMILY, a, n);
 558 }
 559