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 #include <string>
  15 #include "configreader.h"
  16 #include "socket.h"
  17 #include "inspircd.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 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 sockfd, insp_sockaddr client, insp_sockaddr server, int port, char* addr) : ServerInstance(Instance), desc("plaintext")
  40 {
  41         this->SetFd(sockfd);
  42         if (!Instance->BindSocket(this->fd,port,addr))
  43                 this->fd = -1;
  44 #ifdef IPV6
  45         if ((!*addr) || (strchr(addr,':')))
  46                 this->family = AF_INET6;
  47         else
  48                 this->family = AF_INET;
  49 #else
  50         this->family = AF_INET;
  51 #endif
  52 }
  53
  54 ListenSocket::~ListenSocket()
  55 {
  56         if (this->GetFd() > -1)
  57         {
  58                 shutdown(this->fd, 2);
  59                 close(this->fd);
  60                 this->fd = -1;
  61         }
  62 }
  63
  64 void ListenSocket::HandleEvent(EventType et, int errornum)
  65 {
  66         sockaddr* sock_us = new sockaddr[2];    // our port number
  67         sockaddr* client = new sockaddr[2];
  68         socklen_t uslen, length;                // length of our port number
  69         int incomingSockfd, in_port;
  70
  71 #ifdef IPV6
  72         if (this->family == AF_INET6)
  73         {
  74                 uslen = sizeof(sockaddr_in6);
  75                 length = sizeof(sockaddr_in6);
  76         }
  77         else
  78         {
  79                 uslen = sizeof(sockaddr_in);
  80                 length = sizeof(sockaddr_in);
  81         }
  82 #else
  83         uslen = sizeof(sockaddr_in);
  84         length = sizeof(sockaddr_in);
  85 #endif
  86         incomingSockfd = accept (this->GetFd(), (sockaddr*)client, &length);
  87
  88         if ((incomingSockfd > -1) && (!getsockname(incomingSockfd, sock_us, &uslen)))
  89         {
  90                 char buf[MAXBUF];
  91 #ifdef IPV6
  92                 if (this->family == AF_INET6)
  93                 {
  94                         inet_ntop(AF_INET6, &((const sockaddr_in6*)client)->sin6_addr, buf, sizeof(buf));
  95                         in_port = ntohs(((sockaddr_in6*)sock_us)->sin6_port);
  96                 }
  97                 else
  98                 {
  99                         inet_ntop(AF_INET, &((const sockaddr_in*)client)->sin_addr, buf, sizeof(buf));
 100                         in_port = ntohs(((sockaddr_in*)sock_us)->sin_port);
 101                 }
 102 #else
 103                 inet_ntop(AF_INET, &((const sockaddr_in*)client)->sin_addr, buf, sizeof(buf));
 104                 in_port = ntohs(((sockaddr_in*)sock_us)->sin_port);
 105 #endif
 106                 NonBlocking(incomingSockfd);
 107                 if (ServerInstance->Config->GetIOHook(in_port))
 108                 {
 109                         try
 110                         {
 111                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, buf, in_port);
 112                         }
 113                         catch (CoreException& modexcept)
 114                         {
 115                                 ServerInstance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 116                         }
 117                 }
 118                 ServerInstance->stats->statsAccept++;
 119                 userrec::AddClient(ServerInstance, incomingSockfd, in_port, false, this->family, client);
 120         }
 121         else
 122         {
 123                 shutdown(incomingSockfd,2);
 124                 close(incomingSockfd);
 125                 ServerInstance->stats->statsRefused++;
 126         }
 127         delete[] client;
 128         delete[] sock_us;
 129 }
 130
 131 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
 132 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
 133 {
 134         unsigned int modulus = mask_bits % 8; /* Number of whole bytes in the mask */
 135         unsigned int divisor = mask_bits / 8; /* Remaining bits in the mask after whole bytes are dealt with */
 136
 137         /* First compare the whole bytes, if they dont match, return false */
 138         if (memcmp(address, mask, divisor))
 139                 return false;
 140
 141         /* Now if there are any remainder bits, we compare them with logic AND */
 142         if (modulus)
 143                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
 144                         /* If they dont match, return false */
 145                         return false;
 146
 147         /* The address matches the mask, to mask_bits bits of mask */
 148         return true;
 149 }
 150
 151 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
 152 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
 153 {
 154         return MatchCIDR(address, cidr_mask, false);
 155 }
 156
 157 /* 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
 158  * If you have a lot of hosts to match, youre probably better off building your mask once
 159  * and then using the lower level MatchCIDRBits directly.
 160  *
 161  * This will also attempt to match any leading usernames or nicknames on the mask, using
 162  * match(), when match_with_username is true.
 163  */
 164 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
 165 {
 166         unsigned char addr_raw[16];
 167         unsigned char mask_raw[16];
 168         unsigned int bits = 0;
 169         char* mask = NULL;
 170
 171         /* The caller is trying to match ident@<mask>/bits.
 172          * Chop off the ident@ portion, use match() on it
 173          * seperately.
 174          */
 175         if (match_with_username)
 176         {
 177                 /* Duplicate the strings, and try to find the position
 178                  * of the @ symbol in each */
 179                 char* address_dupe = strdup(address);
 180                 char* cidr_dupe = strdup(cidr_mask);
 181
 182                 /* Use strchr not strrchr, because its going to be nearer to the left */
 183                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 184                 char* username_addr_pos = strrchr(address_dupe, '@');
 185
 186                 /* Both strings have an @ symbol in them */
 187                 if (username_mask_pos && username_addr_pos)
 188                 {
 189                         /* Zero out the location of the @ symbol */
 190                         *username_mask_pos = *username_addr_pos = 0;
 191
 192                         /* Try and match() the strings before the @
 193                          * symbols, and recursively call MatchCIDR without
 194                          * username matching enabled to match the host part.
 195                          */
 196                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 197
 198                         /* Free the stuff we created */
 199                         free(address_dupe);
 200                         free(cidr_dupe);
 201
 202                         /* Return a result */
 203                         return result;
 204                 }
 205                 else
 206                 {
 207                         /* One or both didnt have an @ in,
 208                          * just match as CIDR
 209                          */
 210                         free(address_dupe);
 211                         free(cidr_dupe);
 212                         mask = strdup(cidr_mask);
 213                 }
 214         }
 215         else
 216         {
 217                 /* Make a copy of the cidr mask string,
 218                  * we're going to change it
 219                  */
 220                 mask = strdup(cidr_mask);
 221         }
 222
 223         in_addr  address_in4;
 224         in_addr  mask_in4;
 225
 226
 227         /* Use strrchr for this, its nearer to the right */
 228         char* bits_chars = strrchr(mask,'/');
 229
 230         if (bits_chars)
 231         {
 232                 bits = atoi(bits_chars + 1);
 233                 *bits_chars = 0;
 234         }
 235         else
 236         {
 237                 /* No 'number of bits' field! */
 238                 free(mask);
 239                 return false;
 240         }
 241
 242 #ifdef SUPPORT_IP6LINKS
 243         in6_addr address_in6;
 244         in6_addr mask_in6;
 245
 246         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 247         {
 248                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 249                 {
 250                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 251                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 252
 253                         if (bits > 128)
 254                                 bits = 128;
 255                 }
 256                 else
 257                 {
 258                         /* The address was valid ipv6, but the mask
 259                          * that goes with it wasnt.
 260                          */
 261                         free(mask);
 262                         return false;
 263                 }
 264         }
 265         else
 266 #endif
 267         if (inet_pton(AF_INET, address, &address_in4) > 0)
 268         {
 269                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 270                 {
 271                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 272                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 273
 274                         if (bits > 32)
 275                                 bits = 32;
 276                 }
 277                 else
 278                 {
 279                         /* The address was valid ipv4,
 280                          * but the mask that went with it wasnt.
 281                          */
 282                         free(mask);
 283                         return false;
 284                 }
 285         }
 286         else
 287         {
 288                 /* The address was neither ipv4 or ipv6 */
 289                 free(mask);
 290                 return false;
 291         }
 292
 293         /* Low-level-match the bits in the raw data */
 294         free(mask);
 295         return MatchCIDRBits(addr_raw, mask_raw, bits);
 296 }
 297
 298 void irc::sockets::Blocking(int s)
 299 {
 300         int flags = fcntl(s, F_GETFL, 0);
 301         fcntl(s, F_SETFL, flags ^ O_NONBLOCK);
 302 }
 303
 304 void irc::sockets::NonBlocking(int s)
 305 {
 306         int flags = fcntl(s, F_GETFL, 0);
 307         fcntl(s, F_SETFL, flags | O_NONBLOCK);
 308 }
 309
 310 /** This will bind a socket to a port. It works for UDP/TCP.
 311  * It can only bind to IP addresses, if you wish to bind to hostnames
 312  * you should first resolve them using class 'Resolver'.
 313  */
 314 bool InspIRCd::BindSocket(int sockfd, int port, char* addr, bool dolisten)
 315 {
 316         /* We allocate 2 of these, because sockaddr_in6 is larger than sockaddr (ugh, hax) */
 317         sockaddr* server = new sockaddr[2];
 318         memset(server,0,sizeof(sockaddr)*2);
 319
 320         int ret, size;
 321
 322         if (*addr == '*')
 323                 *addr = 0;
 324
 325 #ifdef IPV6
 326         if (*addr)
 327         {
 328                 /* There is an address here. Is it ipv6? */
 329                 if (strchr(addr,':'))
 330                 {
 331                         /* Yes it is */
 332                         in6_addr addy;
 333                         if (inet_pton(AF_INET6, addr, &addy) < 1)
 334                         {
 335                                 delete[] server;
 336                                 return false;
 337                         }
 338
 339                         ((sockaddr_in6*)server)->sin6_family = AF_INET6;
 340                         memcpy(&(((sockaddr_in6*)server)->sin6_addr), &addy, sizeof(in6_addr));
 341                         ((sockaddr_in6*)server)->sin6_port = htons(port);
 342                         size = sizeof(sockaddr_in6);
 343                 }
 344                 else
 345                 {
 346                         /* No, its not */
 347                         in_addr addy;
 348                         if (inet_pton(AF_INET, addr, &addy) < 1)
 349                         {
 350                                 delete[] server;
 351                                 return false;
 352                         }
 353
 354                         ((sockaddr_in*)server)->sin_family = AF_INET;
 355                         ((sockaddr_in*)server)->sin_addr = addy;
 356                         ((sockaddr_in*)server)->sin_port = htons(port);
 357                         size = sizeof(sockaddr_in);
 358                 }
 359         }
 360         else
 361         {
 362                 if (port == -1)
 363                 {
 364                         /* Port -1: Means UDP IPV4 port binding - Special case
 365                          * used by DNS engine.
 366                          */
 367                         ((sockaddr_in*)server)->sin_family = AF_INET;
 368                         ((sockaddr_in*)server)->sin_addr.s_addr = htonl(INADDR_ANY);
 369                         ((sockaddr_in*)server)->sin_port = 0;
 370                         size = sizeof(sockaddr_in);
 371                 }
 372                 else
 373                 {
 374                         /* Theres no address here, default to ipv6 bind to all */
 375                         ((sockaddr_in6*)server)->sin6_family = AF_INET6;
 376                         memset(&(((sockaddr_in6*)server)->sin6_addr), 0, sizeof(in6_addr));
 377                         ((sockaddr_in6*)server)->sin6_port = htons(port);
 378                         size = sizeof(sockaddr_in6);
 379                 }
 380         }
 381 #else
 382         /* If we aren't built with ipv6, the choice becomes simple */
 383         ((sockaddr_in*)server)->sin_family = AF_INET;
 384         if (*addr)
 385         {
 386                 /* There is an address here. */
 387                 in_addr addy;
 388                 if (inet_pton(AF_INET, addr, &addy) < 1)
 389                 {
 390                         delete[] server;
 391                         return false;
 392                 }
 393                 ((sockaddr_in*)server)->sin_addr = addy;
 394         }
 395         else
 396         {
 397                 /* Bind ipv4 to all */
 398                 ((sockaddr_in*)server)->sin_addr.s_addr = htonl(INADDR_ANY);
 399         }
 400         /* Bind ipv4 port number */
 401         ((sockaddr_in*)server)->sin_port = htons(port);
 402         size = sizeof(sockaddr_in);
 403 #endif
 404         ret = bind(sockfd, server, size);
 405         delete[] server;
 406
 407         if (ret < 0)
 408         {
 409                 return false;
 410         }
 411         else
 412         {
 413                 if (dolisten)
 414                 {
 415                         if (listen(sockfd, Config->MaxConn) == -1)
 416                         {
 417                                 this->Log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 418                                 return false;
 419                         }
 420                         else
 421                         {
 422                                 NonBlocking(sockfd);
 423                                 return true;
 424                         }
 425                 }
 426                 else
 427                 {
 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         struct linger linger = { 0 };
 439 #ifdef IPV6
 440         if (strchr(addr,':') || (!*addr))
 441                 sockfd = socket (PF_INET6, socktype, 0);
 442         else
 443                 sockfd = socket (PF_INET, socktype, 0);
 444         if (sockfd < 0)
 445 #else
 446         if ((sockfd = socket (PF_INET, socktype, 0)) < 0)
 447 #endif
 448         {
 449                 return ERROR;
 450         }
 451         else
 452         {
 453                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 454                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 455                 linger.l_onoff = 1;
 456                 linger.l_linger = 1;
 457                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &linger,sizeof(linger));
 458                 return (sockfd);
 459         }
 460 }
 461
 462 /* XXX: Probably belongs in class InspIRCd */
 463 bool InspIRCd::HasPort(int port, char* addr)
 464 {
 465         for (unsigned long count = 0; count < stats->BoundPortCount; count++)
 466         {
 467                 if ((port == Config->ports[count]) && (!strcasecmp(Config->addrs[count],addr)))
 468                 {
 469                         return true;
 470                 }
 471         }
 472         return false;
 473 }
 474
 475 /* XXX: Probably belongs in class InspIRCd */
 476 int InspIRCd::BindPorts(bool bail, int &ports_found, FailedPortList &failed_ports)
 477 {
 478         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 479         insp_sockaddr client, server;
 480         int clientportcount = 0;
 481         int BoundPortCount = 0;
 482
 483         ports_found = 0;
 484
 485         int InitialPortCount = stats->BoundPortCount;
 486
 487         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 488         {
 489                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 490                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 491                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 492
 493                 if ((!*Type) || (!strcmp(Type,"clients")))
 494                 {
 495                         irc::portparser portrange(configToken, false);
 496                         long portno = -1;
 497                         while ((portno = portrange.GetToken()))
 498                         {
 499                                 if (!HasPort(portno, Addr))
 500                                 {
 501                                         ports_found++;
 502                                         Config->ports[clientportcount+InitialPortCount] = portno;
 503                                         if (*Addr == '*')
 504                                                 *Addr = 0;
 505
 506                                         strlcpy(Config->addrs[clientportcount+InitialPortCount],Addr,256);
 507                                         clientportcount++;
 508                                 }
 509                         }
 510                 }
 511
 512                 if (!bail)
 513                 {
 514                         int PortCount = clientportcount;
 515                         if (PortCount)
 516                         {
 517                                 BoundPortCount = stats->BoundPortCount;
 518                                 for (int count = InitialPortCount; count < InitialPortCount + PortCount; count++)
 519                                 {
 520                                         int fd = OpenTCPSocket(Config->addrs[count]);
 521                                         if (fd == ERROR)
 522                                         {
 523                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 524                                         }
 525                                         else
 526                                         {
 527                                                 Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 528                                                 if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 529                                                 {
 530                                                         if (!SE->AddFd(Config->openSockfd[BoundPortCount]))
 531                                                         {
 532                                                                 this->Log(DEFAULT,"ERK! Failed to add listening port to socket engine!");
 533                                                                 shutdown(Config->openSockfd[BoundPortCount]->GetFd(),2);
 534                                                                 close(Config->openSockfd[BoundPortCount]->GetFd());
 535                                                                 delete Config->openSockfd[BoundPortCount];
 536                                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 537                                                         }
 538                                                         else
 539                                                                 BoundPortCount++;
 540                                                 }
 541                                         }
 542                                 }
 543                                 return InitialPortCount + BoundPortCount;
 544                         }
 545                         return InitialPortCount;
 546                 }
 547         }
 548
 549         int PortCount = clientportcount;
 550
 551         for (int count = 0; count < PortCount; count++)
 552         {
 553                 int fd = OpenTCPSocket(Config->addrs[count]);
 554                 if (fd == ERROR)
 555                 {
 556                         failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 557                 }
 558                 else
 559                 {
 560                         Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 561                         if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 562                         {
 563                                 BoundPortCount++;
 564                         }
 565                         else
 566                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 567                 }
 568         }
 569         return BoundPortCount;
 570 }
 571
 572 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 573 {
 574         static char buf[1024];
 575         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 576         return buf;
 577 }
 578
 579 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 580 {
 581         return inet_pton(AF_FAMILY, a, n);
 582 }
 583