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,client,server,port,addr))
  43                 this->fd = -1;
  44 }
  45
  46 ListenSocket::~ListenSocket()
  47 {
  48         if (this->GetFd() > -1)
  49         {
  50                 shutdown(this->fd, 2);
  51                 close(this->fd);
  52                 this->fd = -1;
  53         }
  54 }
  55
  56 void ListenSocket::HandleEvent(EventType et, int errornum)
  57 {
  58         insp_sockaddr sock_us;  // our port number
  59         socklen_t uslen;        // length of our port number
  60         insp_sockaddr client;
  61         socklen_t length;
  62         int incomingSockfd, in_port;
  63         uslen = sizeof(sock_us);
  64         length = sizeof(client);
  65         incomingSockfd = accept (this->GetFd(),(struct sockaddr*)&client, &length);
  66
  67         if ((incomingSockfd > -1) && (!getsockname(incomingSockfd, (sockaddr*)&sock_us, &uslen)))
  68         {
  69 #ifdef IPV6
  70                 in_port = ntohs(sock_us.sin6_port);
  71 #else
  72                 in_port = ntohs(sock_us.sin_port);
  73 #endif
  74                 NonBlocking(incomingSockfd);
  75                 if (ServerInstance->Config->GetIOHook(in_port))
  76                 {
  77                         try
  78                         {
  79 #ifdef IPV6
  80                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, insp_ntoa(client.sin6_addr), in_port);
  81 #else
  82                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, insp_ntoa(client.sin_addr), in_port);
  83 #endif
  84                         }
  85                         catch (CoreException& modexcept)
  86                         {
  87                                 ServerInstance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
  88                         }
  89                 }
  90                 ServerInstance->stats->statsAccept++;
  91 #ifdef IPV6
  92                 userrec::AddClient(ServerInstance, incomingSockfd, in_port, false, client.sin6_addr);
  93 #else
  94                 userrec::AddClient(ServerInstance, incomingSockfd, in_port, false, client.sin_addr);
  95 #endif
  96         }
  97         else
  98         {
  99                 shutdown(incomingSockfd,2);
 100                 close(incomingSockfd);
 101                 ServerInstance->stats->statsRefused++;
 102         }
 103 }
 104
 105 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
 106 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
 107 {
 108         unsigned int modulus = mask_bits % 8; /* Number of whole bytes in the mask */
 109         unsigned int divisor = mask_bits / 8; /* Remaining bits in the mask after whole bytes are dealt with */
 110
 111         /* First compare the whole bytes, if they dont match, return false */
 112         if (memcmp(address, mask, divisor))
 113                 return false;
 114
 115         /* Now if there are any remainder bits, we compare them with logic AND */
 116         if (modulus)
 117                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
 118                         /* If they dont match, return false */
 119                         return false;
 120
 121         /* The address matches the mask, to mask_bits bits of mask */
 122         return true;
 123 }
 124
 125 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
 126 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
 127 {
 128         return MatchCIDR(address, cidr_mask, false);
 129 }
 130
 131 /* 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
 132  * If you have a lot of hosts to match, youre probably better off building your mask once
 133  * and then using the lower level MatchCIDRBits directly.
 134  *
 135  * This will also attempt to match any leading usernames or nicknames on the mask, using
 136  * match(), when match_with_username is true.
 137  */
 138 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
 139 {
 140         unsigned char addr_raw[16];
 141         unsigned char mask_raw[16];
 142         unsigned int bits = 0;
 143         char* mask = NULL;
 144
 145         /* The caller is trying to match ident@<mask>/bits.
 146          * Chop off the ident@ portion, use match() on it
 147          * seperately.
 148          */
 149         if (match_with_username)
 150         {
 151                 /* Duplicate the strings, and try to find the position
 152                  * of the @ symbol in each */
 153                 char* address_dupe = strdup(address);
 154                 char* cidr_dupe = strdup(cidr_mask);
 155
 156                 /* Use strchr not strrchr, because its going to be nearer to the left */
 157                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 158                 char* username_addr_pos = strrchr(address_dupe, '@');
 159
 160                 /* Both strings have an @ symbol in them */
 161                 if (username_mask_pos && username_addr_pos)
 162                 {
 163                         /* Zero out the location of the @ symbol */
 164                         *username_mask_pos = *username_addr_pos = 0;
 165
 166                         /* Try and match() the strings before the @
 167                          * symbols, and recursively call MatchCIDR without
 168                          * username matching enabled to match the host part.
 169                          */
 170                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 171
 172                         /* Free the stuff we created */
 173                         free(address_dupe);
 174                         free(cidr_dupe);
 175
 176                         /* Return a result */
 177                         return result;
 178                 }
 179                 else
 180                 {
 181                         /* One or both didnt have an @ in,
 182                          * just match as CIDR
 183                          */
 184                         free(address_dupe);
 185                         free(cidr_dupe);
 186                         mask = strdup(cidr_mask);
 187                 }
 188         }
 189         else
 190         {
 191                 /* Make a copy of the cidr mask string,
 192                  * we're going to change it
 193                  */
 194                 mask = strdup(cidr_mask);
 195         }
 196
 197         in_addr  address_in4;
 198         in_addr  mask_in4;
 199
 200
 201         /* Use strrchr for this, its nearer to the right */
 202         char* bits_chars = strrchr(mask,'/');
 203
 204         if (bits_chars)
 205         {
 206                 bits = atoi(bits_chars + 1);
 207                 *bits_chars = 0;
 208         }
 209         else
 210         {
 211                 /* No 'number of bits' field! */
 212                 free(mask);
 213                 return false;
 214         }
 215
 216 #ifdef SUPPORT_IP6LINKS
 217         in6_addr address_in6;
 218         in6_addr mask_in6;
 219
 220         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 221         {
 222                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 223                 {
 224                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 225                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 226
 227                         if (bits > 128)
 228                                 bits = 128;
 229                 }
 230                 else
 231                 {
 232                         /* The address was valid ipv6, but the mask
 233                          * that goes with it wasnt.
 234                          */
 235                         free(mask);
 236                         return false;
 237                 }
 238         }
 239         else
 240 #endif
 241         if (inet_pton(AF_INET, address, &address_in4) > 0)
 242         {
 243                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 244                 {
 245                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 246                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 247
 248                         if (bits > 32)
 249                                 bits = 32;
 250                 }
 251                 else
 252                 {
 253                         /* The address was valid ipv4,
 254                          * but the mask that went with it wasnt.
 255                          */
 256                         free(mask);
 257                         return false;
 258                 }
 259         }
 260         else
 261         {
 262                 /* The address was neither ipv4 or ipv6 */
 263                 free(mask);
 264                 return false;
 265         }
 266
 267         /* Low-level-match the bits in the raw data */
 268         free(mask);
 269         return MatchCIDRBits(addr_raw, mask_raw, bits);
 270 }
 271
 272 void irc::sockets::Blocking(int s)
 273 {
 274         int flags = fcntl(s, F_GETFL, 0);
 275         fcntl(s, F_SETFL, flags ^ O_NONBLOCK);
 276 }
 277
 278 void irc::sockets::NonBlocking(int s)
 279 {
 280         int flags = fcntl(s, F_GETFL, 0);
 281         fcntl(s, F_SETFL, flags | O_NONBLOCK);
 282 }
 283
 284 /** This will bind a socket to a port. It works for UDP/TCP.
 285  * It can only bind to IP addresses, if you wish to bind to hostnames
 286  * you should first resolve them using class 'Resolver'.
 287  */
 288 bool InspIRCd::BindSocket(int sockfd, insp_sockaddr client, insp_sockaddr server, int port, char* addr)
 289 {
 290         memset(&server,0,sizeof(server));
 291         insp_inaddr addy;
 292
 293         if (*addr == '*')
 294                 *addr = 0;
 295
 296         if ((*addr) && (insp_aton(addr,&addy) < 1))
 297                 return false;;
 298
 299 #ifdef IPV6
 300         server.sin6_family = AF_FAMILY;
 301 #else
 302         server.sin_family = AF_FAMILY;
 303 #endif
 304         if (!*addr)
 305         {
 306 #ifdef IPV6
 307                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 308 #else
 309                 server.sin_addr.s_addr = htonl(INADDR_ANY);
 310 #endif
 311         }
 312         else
 313         {
 314 #ifdef IPV6
 315                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 316 #else
 317                 server.sin_addr = addy;
 318 #endif
 319         }
 320 #ifdef IPV6
 321         server.sin6_port = htons(port);
 322 #else
 323         server.sin_port = htons(port);
 324 #endif
 325         if (bind(sockfd,(struct sockaddr*)&server,sizeof(server)) < 0)
 326         {
 327                 return false;
 328         }
 329         else
 330         {
 331                 if (listen(sockfd, Config->MaxConn) == -1)
 332                 {
 333                         this->Log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 334                         return false;
 335                 }
 336                 else
 337                 {
 338                         NonBlocking(sockfd);
 339                         return true;
 340                 }
 341         }
 342 }
 343
 344
 345 // Open a TCP Socket
 346 int irc::sockets::OpenTCPSocket()
 347 {
 348         int sockfd;
 349         int on = 1;
 350         struct linger linger = { 0 };
 351
 352         if ((sockfd = socket (AF_FAMILY, SOCK_STREAM, 0)) < 0)
 353         {
 354                 return ERROR;
 355         }
 356         else
 357         {
 358                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 359                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 360                 linger.l_onoff = 1;
 361                 linger.l_linger = 1;
 362                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &linger,sizeof(linger));
 363                 return (sockfd);
 364         }
 365 }
 366
 367 /* XXX: Probably belongs in class InspIRCd */
 368 bool InspIRCd::HasPort(int port, char* addr)
 369 {
 370         for (unsigned long count = 0; count < stats->BoundPortCount; count++)
 371         {
 372                 if ((port == Config->ports[count]) && (!strcasecmp(Config->addrs[count],addr)))
 373                 {
 374                         return true;
 375                 }
 376         }
 377         return false;
 378 }
 379
 380 /* XXX: Probably belongs in class InspIRCd */
 381 int InspIRCd::BindPorts(bool bail, int &ports_found, FailedPortList &failed_ports)
 382 {
 383         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 384         insp_sockaddr client, server;
 385         int clientportcount = 0;
 386         int BoundPortCount = 0;
 387
 388         ports_found = 0;
 389
 390         int InitialPortCount = stats->BoundPortCount;
 391
 392         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 393         {
 394                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 395                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 396                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 397
 398                 if ((!*Type) || (!strcmp(Type,"clients")))
 399                 {
 400                         irc::portparser portrange(configToken, false);
 401                         long portno = -1;
 402                         while ((portno = portrange.GetToken()))
 403                         {
 404                                 if (!HasPort(portno, Addr))
 405                                 {
 406                                         ports_found++;
 407                                         Config->ports[clientportcount+InitialPortCount] = portno;
 408                                         if (*Addr == '*')
 409                                                 *Addr = 0;
 410
 411                                         strlcpy(Config->addrs[clientportcount+InitialPortCount],Addr,256);
 412                                         clientportcount++;
 413                                 }
 414                         }
 415                 }
 416
 417                 if (!bail)
 418                 {
 419                         int PortCount = clientportcount;
 420                         if (PortCount)
 421                         {
 422                                 BoundPortCount = stats->BoundPortCount;
 423                                 for (int count = InitialPortCount; count < InitialPortCount + PortCount; count++)
 424                                 {
 425                                         int fd = OpenTCPSocket();
 426                                         if (fd == ERROR)
 427                                         {
 428                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 429                                         }
 430                                         else
 431                                         {
 432                                                 Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 433                                                 if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 434                                                 {
 435                                                         if (!SE->AddFd(Config->openSockfd[BoundPortCount]))
 436                                                         {
 437                                                                 this->Log(DEFAULT,"ERK! Failed to add listening port to socket engine!");
 438                                                                 shutdown(Config->openSockfd[BoundPortCount]->GetFd(),2);
 439                                                                 close(Config->openSockfd[BoundPortCount]->GetFd());
 440                                                                 delete Config->openSockfd[BoundPortCount];
 441                                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 442                                                         }
 443                                                         else
 444                                                                 BoundPortCount++;
 445                                                 }
 446                                         }
 447                                 }
 448                                 return InitialPortCount + BoundPortCount;
 449                         }
 450                         return InitialPortCount;
 451                 }
 452         }
 453
 454         int PortCount = clientportcount;
 455
 456         for (int count = 0; count < PortCount; count++)
 457         {
 458                 int fd = OpenTCPSocket();
 459                 if (fd == ERROR)
 460                 {
 461                         failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 462                 }
 463                 else
 464                 {
 465                         Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 466                         if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 467                         {
 468                                 BoundPortCount++;
 469                         }
 470                         else
 471                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 472                 }
 473         }
 474         return BoundPortCount;
 475 }
 476
 477 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 478 {
 479         static char buf[1024];
 480         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 481         return buf;
 482 }
 483
 484 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 485 {
 486         return inet_pton(AF_FAMILY, a, n);
 487 }
 488