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