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)
  40 {
  41         this->SetFd(sockfd);
  42         Instance->Log(DEBUG,"Binding to port %s:%d",addr,port);
  43         if (!Instance->BindSocket(this->fd,client,server,port,addr))
  44         {
  45                 Instance->Log(DEBUG,"Binding failed!");
  46                 this->fd = -1;
  47         }
  48 }
  49
  50 void ListenSocket::HandleEvent(EventType et, int errornum)
  51 {
  52         insp_sockaddr sock_us;  // our port number
  53         socklen_t uslen;        // length of our port number
  54         insp_sockaddr client;
  55         socklen_t length;
  56         int incomingSockfd, in_port;
  57
  58         ServerInstance->Log(DEBUG,"Handle ListenSocket event");
  59
  60         uslen = sizeof(sock_us);
  61         length = sizeof(client);
  62         incomingSockfd = accept (this->GetFd(),(struct sockaddr*)&client, &length);
  63
  64         if ((incomingSockfd > -1) && (!getsockname(incomingSockfd, (sockaddr*)&sock_us, &uslen)))
  65         {
  66 #ifdef IPV6
  67                 in_port = ntohs(sock_us.sin6_port);
  68 #else
  69                 in_port = ntohs(sock_us.sin_port);
  70 #endif
  71                 ServerInstance->Log(DEBUG,"Accepted socket %d",incomingSockfd);
  72                 NonBlocking(incomingSockfd);
  73                 if (ServerInstance->Config->GetIOHook(in_port))
  74                 {
  75                         try
  76                         {
  77 #ifdef IPV6
  78                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, insp_ntoa(client.sin6_addr), in_port);
  79 #else
  80                                 ServerInstance->Config->GetIOHook(in_port)->OnRawSocketAccept(incomingSockfd, insp_ntoa(client.sin_addr), in_port);
  81 #endif
  82                         }
  83                         catch (CoreException& modexcept)
  84                         {
  85                                 ServerInstance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
  86                         }
  87                 }
  88                 ServerInstance->stats->statsAccept++;
  89 #ifdef IPV6
  90                 ServerInstance->Log(DEBUG,"Add ipv6 client");
  91                 userrec::AddClient(ServerInstance, incomingSockfd, in_port, false, client.sin6_addr);
  92 #else
  93                 ServerInstance->Log(DEBUG,"Add ipv4 client");
  94                 userrec::AddClient(ServerInstance, incomingSockfd, in_port, false, client.sin_addr);
  95 #endif
  96                 ServerInstance->Log(DEBUG,"Adding client on port %d fd=%d",in_port,incomingSockfd);
  97         }
  98         else
  99         {
 100                 ServerInstance->Log(DEBUG,"Accept failed on fd %d: %s",incomingSockfd,strerror(errno));
 101                 shutdown(incomingSockfd,2);
 102                 close(incomingSockfd);
 103                 ServerInstance->stats->statsRefused++;
 104         }
 105 }
 106
 107 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
 108 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
 109 {
 110         unsigned int modulus = mask_bits % 8; /* Number of whole bytes in the mask */
 111         unsigned int divisor = mask_bits / 8; /* Remaining bits in the mask after whole bytes are dealt with */
 112
 113         /* First compare the whole bytes, if they dont match, return false */
 114         if (memcmp(address, mask, divisor))
 115                 return false;
 116
 117         /* Now if there are any remainder bits, we compare them with logic AND */
 118         if (modulus)
 119                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
 120                         /* If they dont match, return false */
 121                         return false;
 122
 123         /* The address matches the mask, to mask_bits bits of mask */
 124         return true;
 125 }
 126
 127 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
 128 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
 129 {
 130         return MatchCIDR(address, cidr_mask, false);
 131 }
 132
 133 /* 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
 134  * If you have a lot of hosts to match, youre probably better off building your mask once
 135  * and then using the lower level MatchCIDRBits directly.
 136  *
 137  * This will also attempt to match any leading usernames or nicknames on the mask, using
 138  * match(), when match_with_username is true.
 139  */
 140 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
 141 {
 142         unsigned char addr_raw[16];
 143         unsigned char mask_raw[16];
 144         unsigned int bits = 0;
 145         char* mask = NULL;
 146
 147         /* The caller is trying to match ident@<mask>/bits.
 148          * Chop off the ident@ portion, use match() on it
 149          * seperately.
 150          */
 151         if (match_with_username)
 152         {
 153                 /* Duplicate the strings, and try to find the position
 154                  * of the @ symbol in each */
 155                 char* address_dupe = strdup(address);
 156                 char* cidr_dupe = strdup(cidr_mask);
 157
 158                 /* Use strchr not strrchr, because its going to be nearer to the left */
 159                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 160                 char* username_addr_pos = strrchr(address_dupe, '@');
 161
 162                 /* Both strings have an @ symbol in them */
 163                 if (username_mask_pos && username_addr_pos)
 164                 {
 165                         /* Zero out the location of the @ symbol */
 166                         *username_mask_pos = *username_addr_pos = 0;
 167
 168                         /* Try and match() the strings before the @
 169                          * symbols, and recursively call MatchCIDR without
 170                          * username matching enabled to match the host part.
 171                          */
 172                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 173
 174                         /* Free the stuff we created */
 175                         free(address_dupe);
 176                         free(cidr_dupe);
 177
 178                         /* Return a result */
 179                         return result;
 180                 }
 181                 else
 182                 {
 183                         /* One or both didnt have an @ in,
 184                          * just match as CIDR
 185                          */
 186                         free(address_dupe);
 187                         free(cidr_dupe);
 188                         mask = strdup(cidr_mask);
 189                 }
 190         }
 191         else
 192         {
 193                 /* Make a copy of the cidr mask string,
 194                  * we're going to change it
 195                  */
 196                 mask = strdup(cidr_mask);
 197         }
 198
 199         in_addr  address_in4;
 200         in_addr  mask_in4;
 201
 202
 203         /* Use strrchr for this, its nearer to the right */
 204         char* bits_chars = strrchr(mask,'/');
 205
 206         if (bits_chars)
 207         {
 208                 bits = atoi(bits_chars + 1);
 209                 *bits_chars = 0;
 210         }
 211         else
 212         {
 213                 /* No 'number of bits' field! */
 214                 free(mask);
 215                 return false;
 216         }
 217
 218 #ifdef SUPPORT_IP6LINKS
 219         in6_addr address_in6;
 220         in6_addr mask_in6;
 221
 222         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 223         {
 224                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 225                 {
 226                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 227                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 228
 229                         if (bits > 128)
 230                                 bits = 128;
 231                 }
 232                 else
 233                 {
 234                         /* The address was valid ipv6, but the mask
 235                          * that goes with it wasnt.
 236                          */
 237                         free(mask);
 238                         return false;
 239                 }
 240         }
 241         else
 242 #endif
 243         if (inet_pton(AF_INET, address, &address_in4) > 0)
 244         {
 245                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 246                 {
 247                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 248                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 249
 250                         if (bits > 32)
 251                                 bits = 32;
 252                 }
 253                 else
 254                 {
 255                         /* The address was valid ipv4,
 256                          * but the mask that went with it wasnt.
 257                          */
 258                         free(mask);
 259                         return false;
 260                 }
 261         }
 262         else
 263         {
 264                 /* The address was neither ipv4 or ipv6 */
 265                 free(mask);
 266                 return false;
 267         }
 268
 269         /* Low-level-match the bits in the raw data */
 270         free(mask);
 271         return MatchCIDRBits(addr_raw, mask_raw, bits);
 272 }
 273
 274 inline void irc::sockets::Blocking(int s)
 275 {
 276         int flags = fcntl(s, F_GETFL, 0);
 277         fcntl(s, F_SETFL, flags ^ O_NONBLOCK);
 278 }
 279
 280 inline void irc::sockets::NonBlocking(int s)
 281 {
 282         int flags = fcntl(s, F_GETFL, 0);
 283         fcntl(s, F_SETFL, flags | O_NONBLOCK);
 284 }
 285
 286
 287 /** This will bind a socket to a port. It works for UDP/TCP.
 288  * It can only bind to IP addresses, if you wish to bind to hostnames
 289  * you should first resolve them using class 'Resolver'.
 290  */
 291 bool InspIRCd::BindSocket(int sockfd, insp_sockaddr client, insp_sockaddr server, int port, char* addr)
 292 {
 293         memset(&server,0,sizeof(server));
 294         insp_inaddr addy;
 295
 296         if (*addr == '*')
 297                 *addr = 0;
 298
 299         if ((*addr) && (insp_aton(addr,&addy) < 1))
 300         {
 301                 this->Log(DEBUG,"Invalid IP '%s' given to BindSocket()", addr);
 302                 return false;;
 303         }
 304
 305 #ifdef IPV6
 306         server.sin6_family = AF_FAMILY;
 307 #else
 308         server.sin_family = AF_FAMILY;
 309 #endif
 310         if (!*addr)
 311         {
 312 #ifdef IPV6
 313                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 314 #else
 315                 server.sin_addr.s_addr = htonl(INADDR_ANY);
 316 #endif
 317         }
 318         else
 319         {
 320 #ifdef IPV6
 321                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 322 #else
 323                 server.sin_addr = addy;
 324 #endif
 325         }
 326 #ifdef IPV6
 327         server.sin6_port = htons(port);
 328 #else
 329         server.sin_port = htons(port);
 330 #endif
 331         if (bind(sockfd,(struct sockaddr*)&server,sizeof(server)) < 0)
 332         {
 333                 return false;
 334         }
 335         else
 336         {
 337                 this->Log(DEBUG,"Bound port %s:%d",*addr ? addr : "*",port);
 338                 if (listen(sockfd, Config->MaxConn) == -1)
 339                 {
 340                         this->Log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 341                         return false;
 342                 }
 343                 else
 344                 {
 345                         NonBlocking(sockfd);
 346                         return true;
 347                 }
 348         }
 349 }
 350
 351
 352 // Open a TCP Socket
 353 int irc::sockets::OpenTCPSocket()
 354 {
 355         int sockfd;
 356         int on = 1;
 357         struct linger linger = { 0 };
 358
 359         if ((sockfd = socket (AF_FAMILY, SOCK_STREAM, 0)) < 0)
 360         {
 361                 return ERROR;
 362         }
 363         else
 364         {
 365                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 366                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 367                 linger.l_onoff = 1;
 368                 linger.l_linger = 1;
 369                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &linger,sizeof(linger));
 370                 return (sockfd);
 371         }
 372 }
 373
 374 /* XXX: Probably belongs in class InspIRCd */
 375 bool InspIRCd::HasPort(int port, char* addr)
 376 {
 377         for (unsigned long count = 0; count < stats->BoundPortCount; count++)
 378         {
 379                 if ((port == Config->ports[count]) && (!strcasecmp(Config->addrs[count],addr)))
 380                 {
 381                         return true;
 382                 }
 383         }
 384         return false;
 385 }
 386
 387 /* XXX: Probably belongs in class InspIRCd */
 388 int InspIRCd::BindPorts(bool bail, int &ports_found, FailedPortList &failed_ports)
 389 {
 390         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 391         insp_sockaddr client, server;
 392         int clientportcount = 0;
 393         int BoundPortCount = 0;
 394
 395         ports_found = 0;
 396
 397         int InitialPortCount = stats->BoundPortCount;
 398         this->Log(DEBUG,"Initial port count: %d",InitialPortCount);
 399
 400         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 401         {
 402                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 403                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 404                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 405
 406                 if ((!*Type) || (!strcmp(Type,"clients")))
 407                 {
 408                         irc::portparser portrange(configToken, false);
 409                         long portno = -1;
 410                         while ((portno = portrange.GetToken()))
 411                         {
 412                                 if (!HasPort(portno, Addr))
 413                                 {
 414                                         ports_found++;
 415                                         Config->ports[clientportcount+InitialPortCount] = portno;
 416                                         if (*Addr == '*')
 417                                                 *Addr = 0;
 418
 419                                         strlcpy(Config->addrs[clientportcount+InitialPortCount],Addr,256);
 420                                         clientportcount++;
 421                                         this->Log(DEBUG,"NEW binding %s:%d [%s] from config",Addr, portno, Type);
 422                                 }
 423                         }
 424                 }
 425
 426                 if (!bail)
 427                 {
 428                         int PortCount = clientportcount;
 429                         if (PortCount)
 430                         {
 431                                 BoundPortCount = stats->BoundPortCount;
 432                                 for (int count = InitialPortCount; count < InitialPortCount + PortCount; count++)
 433                                 {
 434                                         int fd = OpenTCPSocket();
 435                                         if (fd == ERROR)
 436                                         {
 437                                                 this->Log(DEBUG,"Bad fd %d binding port [%s:%d]",fd,Config->addrs[count],Config->ports[count]);
 438                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 439                                         }
 440                                         else
 441                                         {
 442                                                 Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 443                                                 if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 444                                                 {
 445                                                         if (!SE->AddFd(Config->openSockfd[BoundPortCount]))
 446                                                         {
 447                                                                 this->Log(DEFAULT,"ERK! Failed to add listening port to socket engine!");
 448                                                                 shutdown(Config->openSockfd[BoundPortCount]->GetFd(),2);
 449                                                                 close(Config->openSockfd[BoundPortCount]->GetFd());
 450                                                                 delete Config->openSockfd[BoundPortCount];
 451                                                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 452                                                         }
 453                                                         else
 454                                                                 BoundPortCount++;
 455                                                 }
 456                                         }
 457                                 }
 458                                 return InitialPortCount + BoundPortCount;
 459                         }
 460                         else
 461                         {
 462                                 this->Log(DEBUG,"There is nothing new to bind!");
 463                         }
 464                         return InitialPortCount;
 465                 }
 466         }
 467
 468         int PortCount = clientportcount;
 469
 470         for (int count = 0; count < PortCount; count++)
 471         {
 472                 int fd = OpenTCPSocket();
 473                 if (fd == ERROR)
 474                 {
 475                         this->Log(DEBUG,"Bad fd %d binding port [%s:%d]",fd,Config->addrs[count],Config->ports[count]);
 476                         failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 477                 }
 478                 else
 479                 {
 480                         Config->openSockfd[BoundPortCount] = new ListenSocket(this,fd,client,server,Config->ports[count],Config->addrs[count]);
 481                         if (Config->openSockfd[BoundPortCount]->GetFd() > -1)
 482                         {
 483                                 BoundPortCount++;
 484                         }
 485                         else
 486                                 failed_ports.push_back(std::make_pair(Config->addrs[count],Config->ports[count]));
 487                 }
 488         }
 489         return BoundPortCount;
 490 }
 491
 492 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 493 {
 494         static char buf[1024];
 495         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 496         return buf;
 497 }
 498
 499 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 500 {
 501         return inet_pton(AF_FAMILY, a, n);
 502 }
 503