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                 ServerInstance->SE->DelFd(this);
  59                 ServerInstance->Log(DEBUG,"Shut down listener on fd %d", this->fd);
  60                 if (shutdown(this->fd, 2) || close(this->fd))
  61                         ServerInstance->Log(DEBUG,"Failed to cancel listener: %s", strerror(errno));
  62                 this->fd = -1;
  63         }
  64 }
  65
  66 void ListenSocket::HandleEvent(EventType et, int errornum)
  67 {
  68         sockaddr* sock_us = new sockaddr[2];    // our port number
  69         sockaddr* client = new sockaddr[2];
  70         socklen_t uslen, length;                // length of our port number
  71         int incomingSockfd, in_port;
  72
  73 #ifdef IPV6
  74         if (this->family == AF_INET6)
  75         {
  76                 uslen = sizeof(sockaddr_in6);
  77                 length = sizeof(sockaddr_in6);
  78         }
  79         else
  80         {
  81                 uslen = sizeof(sockaddr_in);
  82                 length = sizeof(sockaddr_in);
  83         }
  84 #else
  85         uslen = sizeof(sockaddr_in);
  86         length = sizeof(sockaddr_in);
  87 #endif
  88         incomingSockfd = accept (this->GetFd(), (sockaddr*)client, &length);
  89
  90         if ((incomingSockfd > -1) && (!getsockname(incomingSockfd, 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                 {
 101                         inet_ntop(AF_INET, &((const sockaddr_in*)client)->sin_addr, buf, sizeof(buf));
 102                         in_port = ntohs(((sockaddr_in*)sock_us)->sin_port);
 103                 }
 104 #else
 105                 inet_ntop(AF_INET, &((const sockaddr_in*)client)->sin_addr, buf, sizeof(buf));
 106                 in_port = ntohs(((sockaddr_in*)sock_us)->sin_port);
 107 #endif
 108                 NonBlocking(incomingSockfd);
 109                 if (ServerInstance->Config->GetIOHook(in_port))
 110                 {
 111                         try
 112                         {
 113                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, buf, in_port);
 114                         }
 115                         catch (CoreException& modexcept)
 116                         {
 117                                 ServerInstance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 118                         }
 119                 }
 120                 ServerInstance->stats->statsAccept++;
 121                 userrec::AddClient(ServerInstance, incomingSockfd, in_port, false, this->family, client);
 122         }
 123         else
 124         {
 125                 shutdown(incomingSockfd,2);
 126                 close(incomingSockfd);
 127                 ServerInstance->stats->statsRefused++;
 128         }
 129         delete[] client;
 130         delete[] sock_us;
 131 }
 132
 133 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
 134 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
 135 {
 136         unsigned int modulus = mask_bits % 8; /* Number of whole bytes in the mask */
 137         unsigned int divisor = mask_bits / 8; /* Remaining bits in the mask after whole bytes are dealt with */
 138
 139         /* First compare the whole bytes, if they dont match, return false */
 140         if (memcmp(address, mask, divisor))
 141                 return false;
 142
 143         /* Now if there are any remainder bits, we compare them with logic AND */
 144         if (modulus)
 145                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
 146                         /* If they dont match, return false */
 147                         return false;
 148
 149         /* The address matches the mask, to mask_bits bits of mask */
 150         return true;
 151 }
 152
 153 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
 154 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
 155 {
 156         return MatchCIDR(address, cidr_mask, false);
 157 }
 158
 159 /* 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
 160  * If you have a lot of hosts to match, youre probably better off building your mask once
 161  * and then using the lower level MatchCIDRBits directly.
 162  *
 163  * This will also attempt to match any leading usernames or nicknames on the mask, using
 164  * match(), when match_with_username is true.
 165  */
 166 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
 167 {
 168         unsigned char addr_raw[16];
 169         unsigned char mask_raw[16];
 170         unsigned int bits = 0;
 171         char* mask = NULL;
 172
 173         /* The caller is trying to match ident@<mask>/bits.
 174          * Chop off the ident@ portion, use match() on it
 175          * seperately.
 176          */
 177         if (match_with_username)
 178         {
 179                 /* Duplicate the strings, and try to find the position
 180                  * of the @ symbol in each */
 181                 char* address_dupe = strdup(address);
 182                 char* cidr_dupe = strdup(cidr_mask);
 183
 184                 /* Use strchr not strrchr, because its going to be nearer to the left */
 185                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 186                 char* username_addr_pos = strrchr(address_dupe, '@');
 187
 188                 /* Both strings have an @ symbol in them */
 189                 if (username_mask_pos && username_addr_pos)
 190                 {
 191                         /* Zero out the location of the @ symbol */
 192                         *username_mask_pos = *username_addr_pos = 0;
 193
 194                         /* Try and match() the strings before the @
 195                          * symbols, and recursively call MatchCIDR without
 196                          * username matching enabled to match the host part.
 197                          */
 198                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 199
 200                         /* Free the stuff we created */
 201                         free(address_dupe);
 202                         free(cidr_dupe);
 203
 204                         /* Return a result */
 205                         return result;
 206                 }
 207                 else
 208                 {
 209                         /* One or both didnt have an @ in,
 210                          * just match as CIDR
 211                          */
 212                         free(address_dupe);
 213                         free(cidr_dupe);
 214                         mask = strdup(cidr_mask);
 215                 }
 216         }
 217         else
 218         {
 219                 /* Make a copy of the cidr mask string,
 220                  * we're going to change it
 221                  */
 222                 mask = strdup(cidr_mask);
 223         }
 224
 225         in_addr  address_in4;
 226         in_addr  mask_in4;
 227
 228
 229         /* Use strrchr for this, its nearer to the right */
 230         char* bits_chars = strrchr(mask,'/');
 231
 232         if (bits_chars)
 233         {
 234                 bits = atoi(bits_chars + 1);
 235                 *bits_chars = 0;
 236         }
 237         else
 238         {
 239                 /* No 'number of bits' field! */
 240                 free(mask);
 241                 return false;
 242         }
 243
 244 #ifdef SUPPORT_IP6LINKS
 245         in6_addr address_in6;
 246         in6_addr mask_in6;
 247
 248         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 249         {
 250                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 251                 {
 252                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 253                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 254
 255                         if (bits > 128)
 256                                 bits = 128;
 257                 }
 258                 else
 259                 {
 260                         /* The address was valid ipv6, but the mask
 261                          * that goes with it wasnt.
 262                          */
 263                         free(mask);
 264                         return false;
 265                 }
 266         }
 267         else
 268 #endif
 269         if (inet_pton(AF_INET, address, &address_in4) > 0)
 270         {
 271                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 272                 {
 273                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 274                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 275
 276                         if (bits > 32)
 277                                 bits = 32;
 278                 }
 279                 else
 280                 {
 281                         /* The address was valid ipv4,
 282                          * but the mask that went with it wasnt.
 283                          */
 284                         free(mask);
 285                         return false;
 286                 }
 287         }
 288         else
 289         {
 290                 /* The address was neither ipv4 or ipv6 */
 291                 free(mask);
 292                 return false;
 293         }
 294
 295         /* Low-level-match the bits in the raw data */
 296         free(mask);
 297         return MatchCIDRBits(addr_raw, mask_raw, bits);
 298 }
 299
 300 void irc::sockets::Blocking(int s)
 301 {
 302         int flags = fcntl(s, F_GETFL, 0);
 303         fcntl(s, F_SETFL, flags ^ O_NONBLOCK);
 304 }
 305
 306 void irc::sockets::NonBlocking(int s)
 307 {
 308         int flags = fcntl(s, F_GETFL, 0);
 309         fcntl(s, F_SETFL, flags | O_NONBLOCK);
 310 }
 311
 312 /** This will bind a socket to a port. It works for UDP/TCP.
 313  * It can only bind to IP addresses, if you wish to bind to hostnames
 314  * you should first resolve them using class 'Resolver'.
 315  */
 316 bool InspIRCd::BindSocket(int sockfd, int port, char* addr, bool dolisten)
 317 {
 318         /* We allocate 2 of these, because sockaddr_in6 is larger than sockaddr (ugh, hax) */
 319         sockaddr* server = new sockaddr[2];
 320         memset(server,0,sizeof(sockaddr)*2);
 321
 322         int ret, size;
 323
 324         if (*addr == '*')
 325                 *addr = 0;
 326
 327 #ifdef IPV6
 328         if (*addr)
 329         {
 330                 /* There is an address here. Is it ipv6? */
 331                 if (strchr(addr,':'))
 332                 {
 333                         /* Yes it is */
 334                         in6_addr addy;
 335                         if (inet_pton(AF_INET6, addr, &addy) < 1)
 336                         {
 337                                 delete[] server;
 338                                 return false;
 339                         }
 340
 341                         ((sockaddr_in6*)server)->sin6_family = AF_INET6;
 342                         memcpy(&(((sockaddr_in6*)server)->sin6_addr), &addy, sizeof(in6_addr));
 343                         ((sockaddr_in6*)server)->sin6_port = htons(port);
 344                         size = sizeof(sockaddr_in6);
 345                 }
 346                 else
 347                 {
 348                         /* No, its not */
 349                         in_addr addy;
 350                         if (inet_pton(AF_INET, addr, &addy) < 1)
 351                         {
 352                                 delete[] server;
 353                                 return false;
 354                         }
 355
 356                         ((sockaddr_in*)server)->sin_family = AF_INET;
 357                         ((sockaddr_in*)server)->sin_addr = addy;
 358                         ((sockaddr_in*)server)->sin_port = htons(port);
 359                         size = sizeof(sockaddr_in);
 360                 }
 361         }
 362         else
 363         {
 364                 if (port == -1)
 365                 {
 366                         /* Port -1: Means UDP IPV4 port binding - Special case
 367                          * used by DNS engine.
 368                          */
 369                         ((sockaddr_in*)server)->sin_family = AF_INET;
 370                         ((sockaddr_in*)server)->sin_addr.s_addr = htonl(INADDR_ANY);
 371                         ((sockaddr_in*)server)->sin_port = 0;
 372                         size = sizeof(sockaddr_in);
 373                 }
 374                 else
 375                 {
 376                         /* Theres no address here, default to ipv6 bind to all */
 377                         ((sockaddr_in6*)server)->sin6_family = AF_INET6;
 378                         memset(&(((sockaddr_in6*)server)->sin6_addr), 0, sizeof(in6_addr));
 379                         ((sockaddr_in6*)server)->sin6_port = htons(port);
 380                         size = sizeof(sockaddr_in6);
 381                 }
 382         }
 383 #else
 384         /* If we aren't built with ipv6, the choice becomes simple */
 385         ((sockaddr_in*)server)->sin_family = AF_INET;
 386         if (*addr)
 387         {
 388                 /* There is an address here. */
 389                 in_addr addy;
 390                 if (inet_pton(AF_INET, addr, &addy) < 1)
 391                 {
 392                         delete[] server;
 393                         return false;
 394                 }
 395                 ((sockaddr_in*)server)->sin_addr = addy;
 396         }
 397         else
 398         {
 399                 /* Bind ipv4 to all */
 400                 ((sockaddr_in*)server)->sin_addr.s_addr = htonl(INADDR_ANY);
 401         }
 402         /* Bind ipv4 port number */
 403         ((sockaddr_in*)server)->sin_port = htons(port);
 404         size = sizeof(sockaddr_in);
 405 #endif
 406         ret = bind(sockfd, server, size);
 407         delete[] server;
 408
 409         if (ret < 0)
 410         {
 411                 return false;
 412         }
 413         else
 414         {
 415                 if (dolisten)
 416                 {
 417                         if (listen(sockfd, Config->MaxConn) == -1)
 418                         {
 419                                 this->Log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 420                                 return false;
 421                         }
 422                         else
 423                         {
 424                                 this->Log(DEBUG,"New socket binding for %d with listen: %s:%d", sockfd, addr, port);
 425                                 NonBlocking(sockfd);
 426                                 return true;
 427                         }
 428                 }
 429                 else
 430                 {
 431                         this->Log(DEBUG,"New socket binding for %d without listen: %s:%d", sockfd, addr, port);
 432                         return true;
 433                 }
 434         }
 435 }
 436
 437 // Open a TCP Socket
 438 int irc::sockets::OpenTCPSocket(char* addr, int socktype)
 439 {
 440         int sockfd;
 441         int on = 1;
 442         struct linger linger = { 0 };
 443 #ifdef IPV6
 444         if (strchr(addr,':') || (!*addr))
 445                 sockfd = socket (PF_INET6, socktype, 0);
 446         else
 447                 sockfd = socket (PF_INET, socktype, 0);
 448         if (sockfd < 0)
 449 #else
 450         if ((sockfd = socket (PF_INET, socktype, 0)) < 0)
 451 #endif
 452         {
 453                 return ERROR;
 454         }
 455         else
 456         {
 457                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 458                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 459                 linger.l_onoff = 1;
 460                 linger.l_linger = 1;
 461                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &linger,sizeof(linger));
 462                 return (sockfd);
 463         }
 464 }
 465
 466 /* XXX: Probably belongs in class InspIRCd */
 467 bool InspIRCd::HasPort(int port, char* addr)
 468 {
 469         for (unsigned long count = 0; count < stats->BoundPortCount; count++)
 470         {
 471                 if ((port == Config->ports[count]) && (!strcasecmp(Config->addrs[count],addr)))
 472                 {
 473                         return true;
 474                 }
 475         }
 476         return false;
 477 }
 478
 479 /* XXX: Probably belongs in class InspIRCd */
 480 int InspIRCd::BindPorts(bool bail, int &ports_found, FailedPortList &failed_ports)
 481 {
 482         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 483         insp_sockaddr client, server;
 484         int clientportcount = 0;
 485         int BoundPortCount = 0;
 486
 487         ports_found = 0;
 488
 489         int InitialPortCount = stats->BoundPortCount;
 490
 491         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 492         {
 493                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 494                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 495                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 496
 497                 if ((!*Type) || (!strcmp(Type,"clients")))
 498                 {
 499                         irc::portparser portrange(configToken, false);
 500                         long portno = -1;
 501                         while ((portno = portrange.GetToken()))
 502                         {
 503                                 if (!HasPort(portno, Addr))
 504                                 {
 505                                         ports_found++;
 506                                         Config->ports[clientportcount+InitialPortCount] = portno;
 507                                         if (*Addr == '*')
 508                                                 *Addr = 0;
 509
 510                                         strlcpy(Config->addrs[clientportcount+InitialPortCount],Addr,256);
 511                                         clientportcount++;
 512                                 }
 513                         }
 514                 }
 515
 516                 if (!bail)
 517                 {
 518                         int PortCount = clientportcount;
 519                         if (PortCount)
 520                         {
 521                                 BoundPortCount = stats->BoundPortCount;
 522                                 for (int count = InitialPortCount; count < InitialPortCount + PortCount; count++)
 523                                 {
 524                                         int fd = OpenTCPSocket(Config->addrs[count]);
 525                                         if (fd == ERROR)
 526                                         {
 527                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 528                                         }
 529                                         else
 530                                         {
 531                                                 Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 532                                                 if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 533                                                 {
 534                                                         if (!SE->AddFd(Config->openSockfd[BoundPortCount]))
 535                                                         {
 536                                                                 this->Log(DEFAULT,"ERK! Failed to add listening port to socket engine!");
 537                                                                 shutdown(Config->openSockfd[BoundPortCount]->GetFd(),2);
 538                                                                 close(Config->openSockfd[BoundPortCount]->GetFd());
 539                                                                 delete Config->openSockfd[BoundPortCount];
 540                                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 541                                                         }
 542                                                         else
 543                                                                 BoundPortCount++;
 544                                                 }
 545                                         }
 546                                 }
 547                                 return InitialPortCount + BoundPortCount;
 548                         }
 549                         return InitialPortCount;
 550                 }
 551         }
 552
 553         int PortCount = clientportcount;
 554
 555         for (int count = 0; count < PortCount; count++)
 556         {
 557                 int fd = OpenTCPSocket(Config->addrs[count]);
 558                 if (fd == ERROR)
 559                 {
 560                         failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 561                 }
 562                 else
 563                 {
 564                         Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 565                         if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 566                         {
 567                                 BoundPortCount++;
 568                         }
 569                         else
 570                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 571                 }
 572         }
 573         return BoundPortCount;
 574 }
 575
 576 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 577 {
 578         static char buf[1024];
 579         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 580         return buf;
 581 }
 582
 583 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 584 {
 585         return inet_pton(AF_FAMILY, a, n);
 586 }
 587