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
  26 extern InspIRCd* ServerInstance;
  27 extern time_t TIME;
  28
  29 using namespace std;
  30 using namespace irc::sockets;
  31
  32 /* Used when comparing CIDR masks for the modulus bits left over.
  33  * A lot of ircd's seem to do this:
  34  * ((-1) << (8 - (mask % 8)))
  35  * But imho, it sucks in comparison to a nice neat lookup table.
  36  */
  37 const char inverted_bits[8] = { 0x00, /* 00000000 - 0 bits - never actually used */
  38                                 0x80, /* 10000000 - 1 bits */
  39                                 0xC0, /* 11000000 - 2 bits */
  40                                 0xE0, /* 11100000 - 3 bits */
  41                                 0xF0, /* 11110000 - 4 bits */
  42                                 0xF8, /* 11111000 - 5 bits */
  43                                 0xFC, /* 11111100 - 6 bits */
  44                                 0xFE  /* 11111110 - 7 bits */
  45 };
  46
  47 /* Match raw bytes using CIDR bit matching, used by higher level MatchCIDR() */
  48 bool irc::sockets::MatchCIDRBits(unsigned char* address, unsigned char* mask, unsigned int mask_bits)
  49 {
  50         unsigned int modulus = mask_bits % 8; /* Number of whole bytes in the mask */
  51         unsigned int divisor = mask_bits / 8; /* Remaining bits in the mask after whole bytes are dealt with */
  52
  53         /* First compare the whole bytes, if they dont match, return false */
  54         if (memcmp(address, mask, divisor))
  55                 return false;
  56
  57         /* Now if there are any remainder bits, we compare them with logic AND */
  58         if (modulus)
  59                 if ((address[divisor] & inverted_bits[modulus]) != (mask[divisor] & inverted_bits[modulus]))
  60                         /* If they dont match, return false */
  61                         return false;
  62
  63         /* The address matches the mask, to mask_bits bits of mask */
  64         return true;
  65 }
  66
  67 /* Match CIDR, but dont attempt to match() against leading *!*@ sections */
  68 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask)
  69 {
  70         return MatchCIDR(address, cidr_mask, false);
  71 }
  72
  73 /* 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
  74  * If you have a lot of hosts to match, youre probably better off building your mask once
  75  * and then using the lower level MatchCIDRBits directly.
  76  *
  77  * This will also attempt to match any leading usernames or nicknames on the mask, using
  78  * match(), when match_with_username is true.
  79  */
  80 bool irc::sockets::MatchCIDR(const char* address, const char* cidr_mask, bool match_with_username)
  81 {
  82         unsigned char addr_raw[16];
  83         unsigned char mask_raw[16];
  84         unsigned int bits = 0;
  85         char* mask = NULL;
  86
  87         /* The caller is trying to match ident@<mask>/bits.
  88          * Chop off the ident@ portion, use match() on it
  89          * seperately.
  90          */
  91         if (match_with_username)
  92         {
  93                 /* Duplicate the strings, and try to find the position
  94                  * of the @ symbol in each */
  95                 char* address_dupe = strdup(address);
  96                 char* cidr_dupe = strdup(cidr_mask);
  97
  98                 /* Use strchr not strrchr, because its going to be nearer to the left */
  99                 char* username_mask_pos = strrchr(cidr_dupe, '@');
 100                 char* username_addr_pos = strrchr(address_dupe, '@');
 101
 102                 /* Both strings have an @ symbol in them */
 103                 if (username_mask_pos && username_addr_pos)
 104                 {
 105                         /* Zero out the location of the @ symbol */
 106                         *username_mask_pos = *username_addr_pos = 0;
 107
 108                         /* Try and match() the strings before the @
 109                          * symbols, and recursively call MatchCIDR without
 110                          * username matching enabled to match the host part.
 111                          */
 112                         bool result = (match(address_dupe, cidr_dupe) && MatchCIDR(username_addr_pos + 1, username_mask_pos + 1, false));
 113
 114                         /* Free the stuff we created */
 115                         free(address_dupe);
 116                         free(cidr_dupe);
 117
 118                         /* Return a result */
 119                         return result;
 120                 }
 121                 else
 122                 {
 123                         /* One or both didnt have an @ in,
 124                          * just match as CIDR
 125                          */
 126                         free(address_dupe);
 127                         free(cidr_dupe);
 128                         mask = strdup(cidr_mask);
 129                 }
 130         }
 131         else
 132         {
 133                 /* Make a copy of the cidr mask string,
 134                  * we're going to change it
 135                  */
 136                 mask = strdup(cidr_mask);
 137         }
 138
 139         in_addr  address_in4;
 140         in_addr  mask_in4;
 141
 142
 143         /* Use strrchr for this, its nearer to the right */
 144         char* bits_chars = strrchr(mask,'/');
 145
 146         if (bits_chars)
 147         {
 148                 bits = atoi(bits_chars + 1);
 149                 *bits_chars = 0;
 150         }
 151         else
 152         {
 153                 /* No 'number of bits' field! */
 154                 return false;
 155         }
 156
 157 #ifdef SUPPORT_IP6LINKS
 158         in6_addr address_in6;
 159         in6_addr mask_in6;
 160
 161         if (inet_pton(AF_INET6, address, &address_in6) > 0)
 162         {
 163                 if (inet_pton(AF_INET6, mask, &mask_in6) > 0)
 164                 {
 165                         memcpy(&addr_raw, &address_in6.s6_addr, 16);
 166                         memcpy(&mask_raw, &mask_in6.s6_addr, 16);
 167
 168                         if (bits > 128)
 169                                 bits = 128;
 170                 }
 171                 else
 172                 {
 173                         /* The address was valid ipv6, but the mask
 174                          * that goes with it wasnt.
 175                          */
 176                         free(mask);
 177                         return false;
 178                 }
 179         }
 180         else
 181 #endif
 182         if (inet_pton(AF_INET, address, &address_in4) > 0)
 183         {
 184                 if (inet_pton(AF_INET, mask, &mask_in4) > 0)
 185                 {
 186                         memcpy(&addr_raw, &address_in4.s_addr, 4);
 187                         memcpy(&mask_raw, &mask_in4.s_addr, 4);
 188
 189                         if (bits > 32)
 190                                 bits = 32;
 191                 }
 192                 else
 193                 {
 194                         /* The address was valid ipv4,
 195                          * but the mask that went with it wasnt.
 196                          */
 197                         free(mask);
 198                         return false;
 199                 }
 200         }
 201         else
 202         {
 203                 /* The address was neither ipv4 or ipv6 */
 204                 free(mask);
 205                 return false;
 206         }
 207
 208         /* Low-level-match the bits in the raw data */
 209         free(mask);
 210         return MatchCIDRBits(addr_raw, mask_raw, bits);
 211 }
 212
 213 inline void irc::sockets::Blocking(int s)
 214 {
 215         int flags = fcntl(s, F_GETFL, 0);
 216         fcntl(s, F_SETFL, flags ^ O_NONBLOCK);
 217 }
 218
 219 inline void irc::sockets::NonBlocking(int s)
 220 {
 221         int flags = fcntl(s, F_GETFL, 0);
 222         fcntl(s, F_SETFL, flags | O_NONBLOCK);
 223 }
 224
 225
 226 /** This will bind a socket to a port. It works for UDP/TCP.
 227  * It can only bind to IP addresses, if you wish to bind to hostnames
 228  * you should first resolve them using class 'Resolver'.
 229  */
 230 bool InspIRCd::BindSocket(int sockfd, insp_sockaddr client, insp_sockaddr server, int port, char* addr)
 231 {
 232         memset(&server,0,sizeof(server));
 233         insp_inaddr addy;
 234
 235         if (*addr == '*')
 236                 *addr = 0;
 237
 238         if ((*addr) && (insp_aton(addr,&addy) < 1))
 239         {
 240                 log(DEBUG,"Invalid IP '%s' given to BindSocket()", addr);
 241                 return false;;
 242         }
 243
 244 #ifdef IPV6
 245         server.sin6_family = AF_FAMILY;
 246 #else
 247         server.sin_family = AF_FAMILY;
 248 #endif
 249         if (!*addr)
 250         {
 251 #ifdef IPV6
 252                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 253 #else
 254                 server.sin_addr.s_addr = htonl(INADDR_ANY);
 255 #endif
 256         }
 257         else
 258         {
 259 #ifdef IPV6
 260                 memcpy(&addy, &server.sin6_addr, sizeof(in6_addr));
 261 #else
 262                 server.sin_addr = addy;
 263 #endif
 264         }
 265 #ifdef IPV6
 266         server.sin6_port = htons(port);
 267 #else
 268         server.sin_port = htons(port);
 269 #endif
 270         if (bind(sockfd,(struct sockaddr*)&server,sizeof(server)) < 0)
 271         {
 272                 return false;
 273         }
 274         else
 275         {
 276                 log(DEBUG,"Bound port %s:%d",*addr ? addr : "*",port);
 277                 if (listen(sockfd, Config->MaxConn) == -1)
 278                 {
 279                         log(DEFAULT,"ERROR in listen(): %s",strerror(errno));
 280                         return false;
 281                 }
 282                 else
 283                 {
 284                         NonBlocking(sockfd);
 285                         return true;
 286                 }
 287         }
 288 }
 289
 290
 291 // Open a TCP Socket
 292 int irc::sockets::OpenTCPSocket()
 293 {
 294         int sockfd;
 295         int on = 1;
 296         struct linger linger = { 0 };
 297
 298         if ((sockfd = socket (AF_FAMILY, SOCK_STREAM, 0)) < 0)
 299         {
 300                 log(DEFAULT,"Error creating TCP socket: %s",strerror(errno));
 301                 return (ERROR);
 302         }
 303         else
 304         {
 305                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 306                 /* This is BSD compatible, setting l_onoff to 0 is *NOT* http://web.irc.org/mla/ircd-dev/msg02259.html */
 307                 linger.l_onoff = 1;
 308                 linger.l_linger = 1;
 309                 setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &linger,sizeof(linger));
 310                 return (sockfd);
 311         }
 312 }
 313
 314 /* XXX: Probably belongs in class InspIRCd */
 315 bool InspIRCd::HasPort(int port, char* addr)
 316 {
 317         for (unsigned long count = 0; count < stats->BoundPortCount; count++)
 318         {
 319                 if ((port == Config->ports[count]) && (!strcasecmp(Config->addrs[count],addr)))
 320                 {
 321                         return true;
 322                 }
 323         }
 324         return false;
 325 }
 326
 327 /* XXX: Probably belongs in class InspIRCd */
 328 int InspIRCd::BindPorts(bool bail)
 329 {
 330         char configToken[MAXBUF], Addr[MAXBUF], Type[MAXBUF];
 331         insp_sockaddr client, server;
 332         int clientportcount = 0;
 333         int BoundPortCount = 0;
 334
 335         if (!bail)
 336         {
 337                 int InitialPortCount = stats->BoundPortCount;
 338                 log(DEBUG,"Initial port count: %d",InitialPortCount);
 339
 340                 for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 341                 {
 342                         Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 343                         Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 344                         Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 345
 346                         if (((!*Type) || (!strcmp(Type,"clients"))) && (!HasPort(atoi(configToken),Addr)))
 347                         {
 348                                 // modules handle server bind types now
 349                                 Config->ports[clientportcount+InitialPortCount] = atoi(configToken);
 350                                 if (*Addr == '*')
 351                                         *Addr = 0;
 352
 353                                 strlcpy(Config->addrs[clientportcount+InitialPortCount],Addr,256);
 354                                 clientportcount++;
 355                                 log(DEBUG,"NEW binding %s:%s [%s] from config",Addr,configToken, Type);
 356                         }
 357                 }
 358                 int PortCount = clientportcount;
 359                 if (PortCount)
 360                 {
 361                         for (int count = InitialPortCount; count < InitialPortCount + PortCount; count++)
 362                         {
 363                                 if ((Config->openSockfd[count] = OpenTCPSocket()) == ERROR)
 364                                 {
 365                                         log(DEBUG,"Bad fd %d binding port [%s:%d]",Config->openSockfd[count],Config->addrs[count],Config->ports[count]);
 366                                 }
 367                                 else
 368                                 {
 369                                         if (!BindSocket(Config->openSockfd[count],client,server,Config->ports[count],Config->addrs[count]))
 370                                         {
 371                                                 log(DEFAULT,"Failed to bind port [%s:%d]: %s",Config->addrs[count],Config->ports[count],strerror(errno));
 372                                         }
 373                                         else
 374                                         {
 375                                                 /* Associate the new open port with a slot in the socket engine */
 376                                                 if (Config->openSockfd[count] > -1)
 377                                                 {
 378                                                         if (!SE->AddFd(Config->openSockfd[count],true,X_LISTEN))
 379                                                         {
 380                                                                 log(DEFAULT,"ERK! Failed to add listening port to socket engine!");
 381                                                                 shutdown(Config->openSockfd[count],2);
 382                                                                 close(Config->openSockfd[count]);
 383                                                         }
 384                                                         else
 385                                                                 BoundPortCount++;
 386                                                 }
 387                                         }
 388                                 }
 389                         }
 390                         return InitialPortCount + BoundPortCount;
 391                 }
 392                 else
 393                 {
 394                         log(DEBUG,"There is nothing new to bind!");
 395                 }
 396                 return InitialPortCount;
 397         }
 398
 399         for (int count = 0; count < Config->ConfValueEnum(Config->config_data, "bind"); count++)
 400         {
 401                 Config->ConfValue(Config->config_data, "bind", "port", count, configToken, MAXBUF);
 402                 Config->ConfValue(Config->config_data, "bind", "address", count, Addr, MAXBUF);
 403                 Config->ConfValue(Config->config_data, "bind", "type", count, Type, MAXBUF);
 404
 405                 if ((!*Type) || (!strcmp(Type,"clients")))
 406                 {
 407                         // modules handle server bind types now
 408                         Config->ports[clientportcount] = atoi(configToken);
 409
 410                         // If the client put bind "*", this is an unrealism.
 411                         // We don't actually support this as documented, but
 412                         // i got fed up of people trying it, so now it converts
 413                         // it to an empty string meaning the same 'bind to all'.
 414                         if (*Addr == '*')
 415                                 *Addr = 0;
 416
 417                         strlcpy(Config->addrs[clientportcount],Addr,256);
 418                         clientportcount++;
 419                         log(DEBUG,"Binding %s:%s [%s] from config",Addr,configToken, Type);
 420                 }
 421         }
 422
 423         int PortCount = clientportcount;
 424
 425         for (int count = 0; count < PortCount; count++)
 426         {
 427                 if ((Config->openSockfd[BoundPortCount] = OpenTCPSocket()) == ERROR)
 428                 {
 429                         log(DEBUG,"Bad fd %d binding port [%s:%d]",Config->openSockfd[BoundPortCount],Config->addrs[count],Config->ports[count]);
 430                 }
 431                 else
 432                 {
 433                         if (!BindSocket(Config->openSockfd[BoundPortCount],client,server,Config->ports[count],Config->addrs[count]))
 434                         {
 435                                 log(DEFAULT,"Failed to bind port [%s:%d]: %s",Config->addrs[count],Config->ports[count],strerror(errno));
 436                         }
 437                         else
 438                         {
 439                                 /* well we at least bound to one socket so we'll continue */
 440                                 BoundPortCount++;
 441                         }
 442                 }
 443         }
 444         return BoundPortCount;
 445 }
 446
 447 const char* irc::sockets::insp_ntoa(insp_inaddr n)
 448 {
 449         static char buf[1024];
 450         inet_ntop(AF_FAMILY, &n, buf, sizeof(buf));
 451         return buf;
 452 }
 453
 454 int irc::sockets::insp_aton(const char* a, insp_inaddr* n)
 455 {
 456         return inet_pton(AF_FAMILY, a, n);
 457 }
 458