src/socket.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 #include <string>
  18 #include "configreader.h"
  19 #include "socket.h"
  20 #include "inspircd.h"
  21 #include "inspstring.h"
  22 #include "helperfuncs.h"
  23 #include "socketengine.h"
  24 #include "wildcard.h"
  25 #include "message.h"
  26
  27 extern InspIRCd* ServerInstance;
  28 extern ServerConfig* Config;
  29 extern time_t TIME;
  30
  31 /* Used when comparing CIDR masks for the modulus bits left over.
  32  * A lot of ircd's seem to do this:
  33  * ((-1) << (8 - (mask % 8)))
  34  * But imho, it sucks in comparison to a nice neat lookup table.
  35  */
  36 const char inverted_bits[8] = { 0x00, /* 00000000 - 0 bits - never actually used */
  37                                 0x80, /* 10000000 - 1 bits */
  38                                 0xC0, /* 11000000 - 2 bits */
  39                                 0xE0, /* 11100000 - 3 bits */
  40                                 0xF0, /* 11110000 - 4 bits */
  41                                 0xF8, /* 11111000 - 5 bits */
  42                                 0xFC, /* 11111100 - 6 bits */
  43                                 0xFE  /* 11111110 - 7 bits */
  44 };
  45
  46 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
  47 bool MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
  48 {
  49         unsigned int modulus = mask_bits % 8; /* Number of whole bytes in the mask */
  50         unsigned int divisor = mask_bits / 8; /* Remaining bits in the mask after whole bytes are dealt with */
  51
  52         /* First compare the whole bytes, if they dont match, return false */
  53         if (memcmp(address, mask, divisor))
  54                 return false;
  55
  56         /* Now if there are any remainder bits, we compare them with logic AND */
  57         if (modulus)
  58                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
  59                         /* If they dont match, return false */
  60                         return false;
  61
  62         /* The address matches the mask, to mask_bits bits of mask */
  63         return true;
  64 }
  65
  66 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
  67 bool MatchCIDR(const char* address, const char* cidr_mask)
  68 {
  69         return MatchCIDR(address, cidr_mask, false);
  70 }
  71
  72 /* 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
  73  * If you have a lot of hosts to match, youre probably better off building your mask once
  74  * and then using the lower level MatchCIDRBits directly.
  75  *
  76  * This will also attempt to match any leading usernames or nicknames on the mask, using
  77  * match(), when match_with_username is true.
  78  */
  79 bool MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
  80 {
  81         unsigned char addr_raw[16];
  82         unsigned char mask_raw[16];
  83         unsigned int bits = 0;
  84         char* mask = NULL;
  85
  86         /* The caller is trying to match ident@<mask>/bits.
  87          * Chop off the ident@ portion, use match() on it
  88          * seperately.
  89          */
  90         if (match_with_username)
  91         {
  92                 /* Duplicate the strings, and try to find the position
  93                  * of the @ symbol in each */
  94                 char* address_dupe = strdup(address);
  95                 char* cidr_dupe = strdup(cidr_mask);
  96
  97                 /* Use strchr not strrchr, because its going to be nearer to the left */
  98                 char* username_mask_pos = strrchr(cidr_dupe, '@');
  99                 char* username_addr_pos = strrchr(address_dupe, '@');
 100
 101                 /* Both strings have an @ symbol in them */
 102                 if (username_mask_pos && username_addr_pos)
 103                 {
 104                         /* Zero out the location of the @ symbol */
 105                         *username_mask_pos = *username_addr_pos = 0;
 106
 107                         /* Try and match() the strings before the @
 108                          * symbols, and recursively call MatchCIDR without
 109                          * username matching enabled to match the host part.
 110                          */
 111                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 112
 113                         /* Free the stuff we created */
 114                         free(address_dupe);
 115                         free(cidr_dupe);
 116
 117                         /* Return a result */
 118                         return result;
 119                 }
 120                 else
 121                 {
 122                         /* One or both didnt have an @ in,
 123                          * just match as CIDR
 124                          */
 125                         free(address_dupe);
 126                         free(cidr_dupe);
 127                         mask = strdup(cidr_mask);
 128                 }
 129         }
 130         else
 131         {
 132                 /* Make a copy of the cidr mask string,
 133                  * we're going to change it
 134                  */
 135                 mask = strdup(cidr_mask);
 136         }
 137
 138         in_addr  address_in4;
 139         in_addr  mask_in4;
 140
 141
 142         /* Use strrchr for this, its nearer to the right */
 143         char* bits_chars = strrchr(mask,'/');
 144
 145         if (bits_chars)
 146         {
 147                 bits = atoi(bits_chars + 1);
 148                 *bits_chars = 0;
 149         }
 150         else
 151         {
 152                 /* No 'number of bits' field! */
 153                 return false;
 154         }
 155
 156 #ifdef SUPPORT_IP6LINKS
 157         in6_addr address_in6;
 158         in6_addr mask_in6;
 159
 160         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 161         {
 162                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 163                 {
 164                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 165                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 166
 167                         if (bits > 128)
 168                                 bits = 128;
 169                 }
 170                 else
 171                 {
 172                         /* The address was valid ipv6, but the mask
 173                          * that goes with it wasnt.
 174                          */
 175                         free(mask);
 176                         return false;
 177                 }
 178         }
 179         else
 180 #endif
 181         if (inet_pton(AF_INET, address, &address_in4) > 0)
 182         {
 183                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 184                 {
 185                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 186                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 187
 188                         if (bits > 32)
 189                                 bits = 32;
 190                 }
 191                 else
 192                 {
 193                         /* The address was valid ipv4,
 194                          * but the mask that went with it wasnt.
 195                          */
 196                         free(mask);
 197                         return false;
 198                 }
 199         }
 200         else
 201         {
 202                 /* The address was neither ipv4 or ipv6 */
 203                 free(mask);
 204                 return false;
 205         }
 206
 207         /* Low-level-match the bits in the raw data */
 208         free(mask);
 209         return MatchCIDRBits(addr_raw, mask_raw, bits);
 210 }
 211
 212 inline void Blocking(int s)
 213 {
 214         int flags = fcntl(s, F_GETFL, 0);
 215         fcntl(s, F_SETFL, flags ^ O_NONBLOCK);
 216 }
 217
 218 inline void NonBlocking(int s)
 219 {
 220         int flags = fcntl(s, F_GETFL, 0);
 221         fcntl(s, F_SETFL, flags | O_NONBLOCK);
 222 }
 223
 224
 225 /** This will bind a socket to a port. It works for UDP/TCP.
 226  * It can only bind to IP addresses, if you wish to bind to hostnames
 227  * you should first resolve them using class 'Resolver'.
 228  */
 229 bool BindSocket(int sockfd, insp_sockaddr client, insp_sockaddr server, int port, char* addr)
 230 {
 231         memset(&server,0,sizeof(server));
 232         insp_inaddr addy;
 233
 234         if (*addr == '*')
 235                 *addr = 0;
 236
 237         if ((*addr) && (insp_aton(addr,&addy) < 1))
 238         {
 239                 log(DEBUG,"Invalid IP '%s' given to BindSocket()", addr);
 240                 return false;;
 241         }
 242
 243 #ifdef IPV6
 244         server.sin6_family = AF_FAMILY;
 245 #else
 246         server.sin_family = AF_FAMILY;
 247 #endif
 248         if (!*addr)
 249         {
 250 #ifdef IPV6
 251                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 252 #else
 253                 server.sin_addr.s_addr = htonl(INADDR_ANY);
 254 #endif
 255         }
 256         else
 257         {
 258 #ifdef IPV6
 259                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 260 #else
 261                 server.sin_addr = addy;
 262 #endif
 263         }
 264 #ifdef IPV6
 265         server.sin6_port = htons(port);
 266 #else
 267         server.sin_port = htons(port);
 268 #endif
 269         if (bind(sockfd,(struct sockaddr*)&server,sizeof(server)) < 0)
 270         {
 271                 return false;
 272         }
 273         else
 274         {
 275                 log(DEBUG,"Bound port %s:%d",*addr ? addr : "*",port);
 276                 if (listen(sockfd, Config->MaxConn) == -1)
 277                 {
 278                         log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 279                         return false;
 280                 }
 281                 else
 282                 {
 283                         NonBlocking(sockfd);
 284                         return true;
 285                 }
 286         }
 287 }
 288
 289
 290 // Open a TCP Socket
 291 int OpenTCPSocket()
 292 {
 293         int sockfd;
 294         int on = 1;
 295         struct linger linger = { 0 };
 296
 297         if ((sockfd = socket (AF_FAMILY, SOCK_STREAM, 0)) < 0)
 298         {
 299                 log(DEFAULT,"Error creating TCP socket: %s",strerror(errno));
 300                 return (ERROR);
 301         }
 302         else
 303         {
 304                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 305                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 306                 linger.l_onoff = 1;
 307                 linger.l_linger = 1;
 308                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &linger,sizeof(linger));
 309                 return (sockfd);
 310         }
 311 }
 312
 313 bool HasPort(int port, char* addr)
 314 {
 315         for (unsigned long count = 0; count < ServerInstance->stats->BoundPortCount; count++)
 316         {
 317                 if ((port == Config->ports[count]) && (!strcasecmp(Config->addrs[count],addr)))
 318                 {
 319                         return true;
 320                 }
 321         }
 322         return false;
 323 }
 324
 325 int BindPorts(bool bail)
 326 {
 327         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 328         insp_sockaddr client, server;
 329         int clientportcount = 0;
 330         int BoundPortCount = 0;
 331
 332         if (!bail)
 333         {
 334                 int InitialPortCount = ServerInstance->stats->BoundPortCount;
 335                 log(DEBUG,"Initial port count: %d",InitialPortCount);
 336
 337                 for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 338                 {
 339                         Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 340                         Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 341                         Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 342
 343                         if (((!*Type) || (!strcmp(Type,"clients"))) && (!HasPort(atoi(configToken),Addr)))
 344                         {
 345                                 // modules handle server bind types now
 346                                 Config->ports[clientportcount+InitialPortCount] = atoi(configToken);
 347                                 if (*Addr == '*')
 348                                         *Addr = 0;
 349
 350                                 strlcpy(Config->addrs[clientportcount+InitialPortCount],Addr,256);
 351                                 clientportcount++;
 352                                 log(DEBUG,"NEW binding %s:%s [%s] from config",Addr,configToken, Type);
 353                         }
 354                 }
 355                 int PortCount = clientportcount;
 356                 if (PortCount)
 357                 {
 358                         for (int count = InitialPortCount; count < InitialPortCount + PortCount; count++)
 359                         {
 360                                 if ((Config->openSockfd[count] = OpenTCPSocket()) == ERROR)
 361                                 {
 362                                         log(DEBUG,"Bad fd %d binding port [%s:%d]",Config->openSockfd[count],Config->addrs[count],Config->ports[count]);
 363                                 }
 364                                 else
 365                                 {
 366                                         if (!BindSocket(Config->openSockfd[count],client,server,Config->ports[count],Config->addrs[count]))
 367                                         {
 368                                                 log(DEFAULT,"Failed to bind port [%s:%d]: %s",Config->addrs[count],Config->ports[count],strerror(errno));
 369                                         }
 370                                         else
 371                                         {
 372                                                 /* Associate the new open port with a slot in the socket engine */
 373                                                 if (Config->openSockfd[count] > -1)
 374                                                 {
 375                                                         if (!ServerInstance->SE->AddFd(Config->openSockfd[count],true,X_LISTEN))
 376                                                         {
 377                                                                 log(DEFAULT,"ERK! Failed to add listening port to socket engine!");
 378                                                                 shutdown(Config->openSockfd[count],2);
 379                                                                 close(Config->openSockfd[count]);
 380                                                         }
 381                                                         else
 382                                                                 BoundPortCount++;
 383                                                 }
 384                                         }
 385                                 }
 386                         }
 387                         return InitialPortCount + BoundPortCount;
 388                 }
 389                 else
 390                 {
 391                         log(DEBUG,"There is nothing new to bind!");
 392                 }
 393                 return InitialPortCount;
 394         }
 395
 396         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 397         {
 398                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 399                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 400                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 401
 402                 if ((!*Type) || (!strcmp(Type,"clients")))
 403                 {
 404                         // modules handle server bind types now
 405                         Config->ports[clientportcount] = atoi(configToken);
 406
 407                         // If the client put bind "*", this is an unrealism.
 408                         // We don't actually support this as documented, but
 409                         // i got fed up of people trying it, so now it converts
 410                         // it to an empty string meaning the same 'bind to all'.
 411                         if (*Addr == '*')
 412                                 *Addr = 0;
 413
 414                         strlcpy(Config->addrs[clientportcount],Addr,256);
 415                         clientportcount++;
 416                         log(DEBUG,"Binding %s:%s [%s] from config",Addr,configToken, Type);
 417                 }
 418         }
 419
 420         int PortCount = clientportcount;
 421
 422         for (int count = 0; count < PortCount; count++)
 423         {
 424                 if ((Config->openSockfd[BoundPortCount] = OpenTCPSocket()) == ERROR)
 425                 {
 426                         log(DEBUG,"Bad fd %d binding port [%s:%d]",Config->openSockfd[BoundPortCount],Config->addrs[count],Config->ports[count]);
 427                 }
 428                 else
 429                 {
 430                         if (!BindSocket(Config->openSockfd[BoundPortCount],client,server,Config->ports[count],Config->addrs[count]))
 431                         {
 432                                 log(DEFAULT,"Failed to bind port [%s:%d]: %s",Config->addrs[count],Config->ports[count],strerror(errno));
 433                         }
 434                         else
 435                         {
 436                                 /* well we at least bound to one socket so we'll continue */
 437                                 BoundPortCount++;
 438                         }
 439                 }
 440         }
 441         return BoundPortCount;
 442 }
 443
 444 const char* insp_ntoa(insp_inaddr n)
 445 {
 446         static char buf[1024];
 447         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 448         return buf;
 449 }
 450
 451 int insp_aton(const char* a, insp_inaddr* n)
 452 {
 453         return inet_pton(AF_FAMILY, a, n);
 454 }
 455