src/socket.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2007 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->Log(DEBUG,"Shut down listener on fd %d", this->fd);
  62                 if (ServerInstance->SE->Shutdown(this, 2) || ServerInstance->SE->Close(this))
  63                         ServerInstance->Log(DEBUG,"Failed to cancel listener: %s", strerror(errno));
  64                 this->fd = -1;
  65         }
  66 }
  67
  68 void ListenSocket::HandleEvent(EventType et, int errornum)
  69 {
  70         sockaddr* sock_us = new sockaddr[2];    // our port number
  71         sockaddr* client = new sockaddr[2];
  72         socklen_t uslen, length;                // length of our port number
  73         int incomingSockfd, in_port;
  74
  75 #ifdef IPV6
  76         if (this->family == AF_INET6)
  77         {
  78                 uslen = sizeof(sockaddr_in6);
  79                 length = sizeof(sockaddr_in6);
  80         }
  81         else
  82 #endif
  83         {
  84                 uslen = sizeof(sockaddr_in);
  85                 length = sizeof(sockaddr_in);
  86         }
  87
  88         incomingSockfd = ServerInstance->SE->Accept(this, (sockaddr*)client, &length);
  89
  90         if ((incomingSockfd > -1) && (!ServerInstance->SE->GetSockName(this, sock_us, &uslen)))
  91         {
  92                 char buf[MAXBUF];
  93 #ifdef IPV6
  94                 if (this->family == AF_INET6)
  95                 {
  96                         inet_ntop(AF_INET6, &((const sockaddr_in6*)client)->sin6_addr, buf, sizeof(buf));
  97                         in_port = ntohs(((sockaddr_in6*)sock_us)->sin6_port);
  98                 }
  99                 else
 100 #endif
 101                 {
 102                         inet_ntop(AF_INET, &((const sockaddr_in*)client)->sin_addr, buf, sizeof(buf));
 103                         in_port = ntohs(((sockaddr_in*)sock_us)->sin_port);
 104                 }
 105
 106                 ServerInstance->SE->NonBlocking(incomingSockfd);
 107
 108                 if (ServerInstance->Config->GetIOHook(in_port))
 109                 {
 110                         try
 111                         {
 112                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, buf, in_port);
 113                         }
 114                         catch (CoreException& modexcept)
 115                         {
 116                                 ServerInstance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 117                         }
 118                 }
 119                 ServerInstance->stats->statsAccept++;
 120                 User::AddClient(ServerInstance, incomingSockfd, in_port, false, this->family, client);
 121         }
 122         else
 123         {
 124                 ServerInstance->SE->Shutdown(incomingSockfd, 2);
 125                 ServerInstance->SE->Close(incomingSockfd);
 126                 ServerInstance->stats->statsRefused++;
 127         }
 128         delete[] client;
 129         delete[] sock_us;
 130 }
 131
 132 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
 133 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
 134 {
 135         unsigned int divisor = mask_bits / 8; /* Number of whole bytes in the mask */
 136         unsigned int modulus = mask_bits % 8; /* Remaining bits in the mask after whole bytes are dealt with */
 137
 138         /* First (this is faster) compare the odd bits with logic ops */
 139         if (modulus)
 140                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
 141                         /* If they dont match, return false */
 142                         return false;
 143
 144         /* Secondly (this is slower) compare the whole bytes */
 145         if (memcmp(address, mask, divisor))
 146                 return false;
 147
 148         /* The address matches the mask, to mask_bits bits of mask */
 149         return true;
 150 }
 151
 152 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
 153 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
 154 {
 155         return MatchCIDR(address, cidr_mask, false);
 156 }
 157
 158 /* 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
 159  * If you have a lot of hosts to match, youre probably better off building your mask once
 160  * and then using the lower level MatchCIDRBits directly.
 161  *
 162  * This will also attempt to match any leading usernames or nicknames on the mask, using
 163  * match(), when match_with_username is true.
 164  */
 165 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
 166 {
 167         unsigned char addr_raw[16];
 168         unsigned char mask_raw[16];
 169         unsigned int bits = 0;
 170         char* mask = NULL;
 171
 172         /* The caller is trying to match ident@<mask>/bits.
 173          * Chop off the ident@ portion, use match() on it
 174          * seperately.
 175          */
 176         if (match_with_username)
 177         {
 178                 /* Duplicate the strings, and try to find the position
 179                  * of the @ symbol in each */
 180                 char* address_dupe = strdup(address);
 181                 char* cidr_dupe = strdup(cidr_mask);
 182
 183                 /* Use strchr not strrchr, because its going to be nearer to the left */
 184                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 185                 char* username_addr_pos = strrchr(address_dupe, '@');
 186
 187                 /* Both strings have an @ symbol in them */
 188                 if (username_mask_pos && username_addr_pos)
 189                 {
 190                         /* Zero out the location of the @ symbol */
 191                         *username_mask_pos = *username_addr_pos = 0;
 192
 193                         /* Try and match() the strings before the @
 194                          * symbols, and recursively call MatchCIDR without
 195                          * username matching enabled to match the host part.
 196                          */
 197                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 198
 199                         /* Free the stuff we created */
 200                         free(address_dupe);
 201                         free(cidr_dupe);
 202
 203                         /* Return a result */
 204                         return result;
 205                 }
 206                 else
 207                 {
 208                         /* One or both didnt have an @ in,
 209                          * just match as CIDR
 210                          */
 211                         free(address_dupe);
 212                         free(cidr_dupe);
 213                         mask = strdup(cidr_mask);
 214                 }
 215         }
 216         else
 217         {
 218                 /* Make a copy of the cidr mask string,
 219                  * we're going to change it
 220                  */
 221                 mask = strdup(cidr_mask);
 222         }
 223
 224         in_addr  address_in4;
 225         in_addr  mask_in4;
 226
 227
 228         /* Use strrchr for this, its nearer to the right */
 229         char* bits_chars = strrchr(mask,'/');
 230
 231         if (bits_chars)
 232         {
 233                 bits = atoi(bits_chars + 1);
 234                 *bits_chars = 0;
 235         }
 236         else
 237         {
 238                 /* No 'number of bits' field! */
 239                 free(mask);
 240                 return false;
 241         }
 242
 243 #ifdef SUPPORT_IP6LINKS
 244         in6_addr address_in6;
 245         in6_addr mask_in6;
 246
 247         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 248         {
 249                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 250                 {
 251                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 252                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 253
 254                         if (bits > 128)
 255                                 bits = 128;
 256                 }
 257                 else
 258                 {
 259                         /* The address was valid ipv6, but the mask
 260                          * that goes with it wasnt.
 261                          */
 262                         free(mask);
 263                         return false;
 264                 }
 265         }
 266         else
 267 #endif
 268         if (inet_pton(AF_INET, address, &address_in4) > 0)
 269         {
 270                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 271                 {
 272                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 273                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 274
 275                         if (bits > 32)
 276                                 bits = 32;
 277                 }
 278                 else
 279                 {
 280                         /* The address was valid ipv4,
 281                          * but the mask that went with it wasnt.
 282                          */
 283                         free(mask);
 284                         return false;
 285                 }
 286         }
 287         else
 288         {
 289                 /* The address was neither ipv4 or ipv6 */
 290                 free(mask);
 291                 return false;
 292         }
 293
 294         /* Low-level-match the bits in the raw data */
 295         free(mask);
 296         return MatchCIDRBits(addr_raw, mask_raw, bits);
 297 }
 298
 299 /** This will bind a socket to a port. It works for UDP/TCP.
 300  * It can only bind to IP addresses, if you wish to bind to hostnames
 301  * you should first resolve them using class 'Resolver'.
 302  */
 303 bool InspIRCd::BindSocket(int sockfd, int port, char* addr, bool dolisten)
 304 {
 305         /* We allocate 2 of these, because sockaddr_in6 is larger than sockaddr (ugh, hax) */
 306         sockaddr* server = new sockaddr[2];
 307         memset(server,0,sizeof(sockaddr)*2);
 308
 309         int ret, size;
 310
 311         if (*addr == '*')
 312                 *addr = 0;
 313
 314 #ifdef IPV6
 315         if (*addr)
 316         {
 317                 /* There is an address here. Is it ipv6? */
 318                 if (strchr(addr,':'))
 319                 {
 320                         /* Yes it is */
 321                         in6_addr addy;
 322                         if (inet_pton(AF_INET6, addr, &addy) < 1)
 323                         {
 324                                 delete[] server;
 325                                 return false;
 326                         }
 327
 328                         ((sockaddr_in6*)server)->sin6_family = AF_INET6;
 329                         memcpy(&(((sockaddr_in6*)server)->sin6_addr), &addy, sizeof(in6_addr));
 330                         ((sockaddr_in6*)server)->sin6_port = htons(port);
 331                         size = sizeof(sockaddr_in6);
 332                 }
 333                 else
 334                 {
 335                         /* No, its not */
 336                         in_addr addy;
 337                         if (inet_pton(AF_INET, addr, &addy) < 1)
 338                         {
 339                                 delete[] server;
 340                                 return false;
 341                         }
 342
 343                         ((sockaddr_in*)server)->sin_family = AF_INET;
 344                         ((sockaddr_in*)server)->sin_addr = addy;
 345                         ((sockaddr_in*)server)->sin_port = htons(port);
 346                         size = sizeof(sockaddr_in);
 347                 }
 348         }
 349         else
 350         {
 351                 if (port == -1)
 352                 {
 353                         /* Port -1: Means UDP IPV4 port binding - Special case
 354                          * used by DNS engine.
 355                          */
 356                         ((sockaddr_in*)server)->sin_family = AF_INET;
 357                         ((sockaddr_in*)server)->sin_addr.s_addr = htonl(INADDR_ANY);
 358                         ((sockaddr_in*)server)->sin_port = 0;
 359                         size = sizeof(sockaddr_in);
 360                 }
 361                 else
 362                 {
 363                         /* Theres no address here, default to ipv6 bind to all */
 364                         ((sockaddr_in6*)server)->sin6_family = AF_INET6;
 365                         memset(&(((sockaddr_in6*)server)->sin6_addr), 0, sizeof(in6_addr));
 366                         ((sockaddr_in6*)server)->sin6_port = htons(port);
 367                         size = sizeof(sockaddr_in6);
 368                 }
 369         }
 370 #else
 371         /* If we aren't built with ipv6, the choice becomes simple */
 372         ((sockaddr_in*)server)->sin_family = AF_INET;
 373         if (*addr)
 374         {
 375                 /* There is an address here. */
 376                 in_addr addy;
 377                 if (inet_pton(AF_INET, addr, &addy) < 1)
 378                 {
 379                         delete[] server;
 380                         return false;
 381                 }
 382                 ((sockaddr_in*)server)->sin_addr = addy;
 383         }
 384         else
 385         {
 386                 /* Bind ipv4 to all */
 387                 ((sockaddr_in*)server)->sin_addr.s_addr = htonl(INADDR_ANY);
 388         }
 389         /* Bind ipv4 port number */
 390         ((sockaddr_in*)server)->sin_port = htons(port);
 391         size = sizeof(sockaddr_in);
 392 #endif
 393         ret = SE->Bind(sockfd, server, size);
 394         delete[] server;
 395
 396         if (ret < 0)
 397         {
 398                 return false;
 399         }
 400         else
 401         {
 402                 if (dolisten)
 403                 {
 404                         if (SE->Listen(sockfd, Config->MaxConn) == -1)
 405                         {
 406                                 this->Log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 407                                 return false;
 408                         }
 409                         else
 410                         {
 411                                 this->Log(DEBUG,"New socket binding for %d with listen: %s:%d", sockfd, addr, port);
 412                                 SE->NonBlocking(sockfd);
 413                                 return true;
 414                         }
 415                 }
 416                 else
 417                 {
 418                         this->Log(DEBUG,"New socket binding for %d without listen: %s:%d", sockfd, addr, port);
 419                         return true;
 420                 }
 421         }
 422 }
 423
 424 // Open a TCP Socket
 425 int irc::sockets::OpenTCPSocket(char* addr, int socktype)
 426 {
 427         int sockfd;
 428         int on = 1;
 429         struct linger linger = { 0 };
 430 #ifdef IPV6
 431         if (strchr(addr,':') || (!*addr))
 432                 sockfd = socket (PF_INET6, socktype, 0);
 433         else
 434                 sockfd = socket (PF_INET, socktype, 0);
 435         if (sockfd < 0)
 436 #else
 437         if ((sockfd = socket (PF_INET, socktype, 0)) < 0)
 438 #endif
 439         {
 440                 return ERROR;
 441         }
 442         else
 443         {
 444                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (char*)&on, sizeof(on));
 445                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 446                 linger.l_onoff = 1;
 447                 linger.l_linger = 1;
 448                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, (char*)&linger,sizeof(linger));
 449                 return (sockfd);
 450         }
 451 }
 452
 453 int InspIRCd::BindPorts(bool bail, int &ports_found, FailedPortList &failed_ports)
 454 {
 455         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 456         int bound = 0;
 457         bool started_with_nothing = (Config->ports.size() == 0);
 458         std::vector<std::pair<std::string, int> > old_ports;
 459
 460         /* XXX: Make a copy of the old ip/port pairs here */
 461         for (std::vector<ListenSocket*>::iterator o = Config->ports.begin(); o != Config->ports.end(); ++o)
 462                 old_ports.push_back(make_pair((*o)->GetIP(), (*o)->GetPort()));
 463
 464         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 465         {
 466                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 467                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 468                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 469
 470                 if (strncmp(Addr, "::ffff:", 7) == 0)
 471                         this->Log(DEFAULT, "Using 4in6 (::ffff:) isn't recommended. You should bind IPv4 addresses directly instead.");
 472
 473                 if ((!*Type) || (!strcmp(Type,"clients")))
 474                 {
 475                         irc::portparser portrange(configToken, false);
 476                         int portno = -1;
 477                         while ((portno = portrange.GetToken()))
 478                         {
 479                                 if (*Addr == '*')
 480                                         *Addr = 0;
 481
 482                                 bool skip = false;
 483                                 for (std::vector<ListenSocket*>::iterator n = Config->ports.begin(); n != Config->ports.end(); ++n)
 484                                 {
 485                                         if (((*n)->GetIP() == Addr) && ((*n)->GetPort() == portno))
 486                                         {
 487                                                 skip = true;
 488                                                 /* XXX: Here, erase from our copy of the list */
 489                                                 for (std::vector<std::pair<std::string, int> >::iterator k = old_ports.begin(); k != old_ports.end(); ++k)
 490                                                 {
 491                                                         if ((k->first == Addr) && (k->second == portno))
 492                                                         {
 493                                                                 old_ports.erase(k);
 494                                                                 break;
 495                                                         }
 496                                                 }
 497                                         }
 498                                 }
 499                                 if (!skip)
 500                                 {
 501                                         ListenSocket* ll = new ListenSocket(this, portno, Addr);
 502                                         if (ll->GetFd() > -1)
 503                                         {
 504                                                 bound++;
 505                                                 Config->ports.push_back(ll);
 506                                         }
 507                                         else
 508                                         {
 509                                                 failed_ports.push_back(std::make_pair(Addr, portno));
 510                                         }
 511                                         ports_found++;
 512                                 }
 513                         }
 514                 }
 515         }
 516
 517         /* XXX: Here, anything left in our copy list, close as removed */
 518         if (!started_with_nothing)
 519         {
 520                 for (size_t k = 0; k < old_ports.size(); ++k)
 521                 {
 522                         for (std::vector<ListenSocket*>::iterator n = Config->ports.begin(); n != Config->ports.end(); ++n)
 523                         {
 524                                 if (((*n)->GetIP() == old_ports[k].first) && ((*n)->GetPort() == old_ports[k].second))
 525                                 {
 526                                         this->Log(DEFAULT,"Port binding %s:%d was removed from the config file, closing.", old_ports[k].first.c_str(), old_ports[k].second);
 527                                         delete *n;
 528                                         Config->ports.erase(n);
 529                                         break;
 530                                 }
 531                         }
 532                 }
 533         }
 534
 535         return bound;
 536 }
 537
 538 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 539 {
 540         static char buf[1024];
 541         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 542         return buf;
 543 }
 544
 545 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 546 {
 547         return inet_pton(AF_FAMILY, a, n);
 548 }
 549