| 1 | /* -*- c-file-style: "linux" -*- |
| 2 | |
| 3 | Copyright (C) 1992-2001 by Andrew Tridgell <tridge@samba.org> |
| 4 | Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.org> |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 19 | */ |
| 20 | |
| 21 | /** |
| 22 | * @file socket.c |
| 23 | * |
| 24 | * Socket functions used in rsync. |
| 25 | * |
| 26 | * This file is now converted to use the new-style getaddrinfo() |
| 27 | * interface, which supports IPv6 but is also supported on recent |
| 28 | * IPv4-only machines. On systems that don't have that interface, we |
| 29 | * emulate it using the KAME implementation. |
| 30 | **/ |
| 31 | |
| 32 | #include "rsync.h" |
| 33 | |
| 34 | /* Establish a proxy connection on an open socket to a web roxy by |
| 35 | * using the CONNECT method. */ |
| 36 | static int establish_proxy_connection(int fd, char *host, int port) |
| 37 | { |
| 38 | char buffer[1024]; |
| 39 | char *cp; |
| 40 | |
| 41 | snprintf(buffer, sizeof(buffer), "CONNECT %s:%d HTTP/1.0\r\n\r\n", host, port); |
| 42 | if (write(fd, buffer, strlen(buffer)) != strlen(buffer)) { |
| 43 | rprintf(FERROR, "failed to write to proxy: %s\n", |
| 44 | strerror(errno)); |
| 45 | return -1; |
| 46 | } |
| 47 | |
| 48 | for (cp = buffer; cp < &buffer[sizeof(buffer) - 1]; cp++) { |
| 49 | if (read(fd, cp, 1) != 1) { |
| 50 | rprintf(FERROR, "failed to read from proxy: %s\n", |
| 51 | strerror(errno)); |
| 52 | return -1; |
| 53 | } |
| 54 | if (*cp == '\n') |
| 55 | break; |
| 56 | } |
| 57 | |
| 58 | if (*cp != '\n') |
| 59 | cp++; |
| 60 | *cp-- = '\0'; |
| 61 | if (*cp == '\r') |
| 62 | *cp = '\0'; |
| 63 | if (strncmp(buffer, "HTTP/", 5) != 0) { |
| 64 | rprintf(FERROR, "bad response from proxy - %s\n", |
| 65 | buffer); |
| 66 | return -1; |
| 67 | } |
| 68 | for (cp = &buffer[5]; isdigit(*cp) || (*cp == '.'); cp++) |
| 69 | ; |
| 70 | while (*cp == ' ') |
| 71 | cp++; |
| 72 | if (*cp != '2') { |
| 73 | rprintf(FERROR, "bad response from proxy - %s\n", |
| 74 | buffer); |
| 75 | return -1; |
| 76 | } |
| 77 | /* throw away the rest of the HTTP header */ |
| 78 | while (1) { |
| 79 | for (cp = buffer; cp < &buffer[sizeof(buffer) - 1]; |
| 80 | cp++) { |
| 81 | if (read(fd, cp, 1) != 1) { |
| 82 | rprintf(FERROR, "failed to read from proxy: %s\n", |
| 83 | strerror(errno)); |
| 84 | return -1; |
| 85 | } |
| 86 | if (*cp == '\n') |
| 87 | break; |
| 88 | } |
| 89 | if ((cp > buffer) && (*cp == '\n')) |
| 90 | cp--; |
| 91 | if ((cp == buffer) && ((*cp == '\n') || (*cp == '\r'))) |
| 92 | break; |
| 93 | } |
| 94 | return 0; |
| 95 | } |
| 96 | |
| 97 | |
| 98 | /** |
| 99 | * Try to set the local address for a newly-created socket. Return -1 |
| 100 | * if this fails. |
| 101 | **/ |
| 102 | int try_bind_local(int s, |
| 103 | int ai_family, int ai_socktype, |
| 104 | const char *bind_address) |
| 105 | { |
| 106 | int error; |
| 107 | struct addrinfo bhints, *bres_all, *r; |
| 108 | |
| 109 | memset(&bhints, 0, sizeof(bhints)); |
| 110 | bhints.ai_family = ai_family; |
| 111 | bhints.ai_socktype = ai_socktype; |
| 112 | bhints.ai_flags = AI_PASSIVE; |
| 113 | if ((error = getaddrinfo(bind_address, NULL, &bhints, &bres_all))) { |
| 114 | rprintf(FERROR, RSYNC_NAME ": getaddrinfo %s: %s\n", |
| 115 | bind_address, gai_strerror(error)); |
| 116 | return -1; |
| 117 | } |
| 118 | |
| 119 | for (r = bres_all; r; r = r->ai_next) { |
| 120 | if (bind(s, r->ai_addr, r->ai_addrlen) == -1) |
| 121 | continue; |
| 122 | return s; |
| 123 | } |
| 124 | |
| 125 | /* no error message; there might be some problem that allows |
| 126 | * creation of the socket but not binding, perhaps if the |
| 127 | * machine has no ipv6 address of this name. */ |
| 128 | return -1; |
| 129 | } |
| 130 | |
| 131 | |
| 132 | /** |
| 133 | * Open a socket to a tcp remote host with the specified port . |
| 134 | * |
| 135 | * Based on code from Warren. Proxy support by Stephen Rothwell. |
| 136 | * getaddrinfo() rewrite contributed by KAME.net. |
| 137 | * |
| 138 | * Now that we support IPv6 we need to look up the remote machine's |
| 139 | * address first, using @p af_hint to set a preference for the type |
| 140 | * of address. Then depending on whether it has v4 or v6 addresses we |
| 141 | * try to open a connection. |
| 142 | * |
| 143 | * The loop allows for machines with some addresses which may not be |
| 144 | * reachable, perhaps because we can't e.g. route ipv6 to that network |
| 145 | * but we can get ip4 packets through. |
| 146 | * |
| 147 | * @param bind_address Local address to use. Normally NULL to bind |
| 148 | * the wildcard address. |
| 149 | * |
| 150 | * @param af_hint Address family, e.g. AF_INET or AF_INET6. |
| 151 | **/ |
| 152 | int open_socket_out(char *host, int port, const char *bind_address, |
| 153 | int af_hint) |
| 154 | { |
| 155 | int type = SOCK_STREAM; |
| 156 | int error; |
| 157 | int s; |
| 158 | struct addrinfo hints, *res0, *res; |
| 159 | char portbuf[10]; |
| 160 | char *h; |
| 161 | int proxied = 0; |
| 162 | char buffer[1024]; |
| 163 | char *cp; |
| 164 | |
| 165 | /* if we have a RSYNC_PROXY env variable then redirect our |
| 166 | * connetcion via a web proxy at the given address. The format |
| 167 | * is hostname:port */ |
| 168 | h = getenv("RSYNC_PROXY"); |
| 169 | proxied = (h != NULL) && (*h != '\0'); |
| 170 | |
| 171 | if (proxied) { |
| 172 | strlcpy(buffer, h, sizeof(buffer)); |
| 173 | cp = strchr(buffer, ':'); |
| 174 | if (cp == NULL) { |
| 175 | rprintf(FERROR, |
| 176 | "invalid proxy specification: should be HOST:PORT\n"); |
| 177 | return -1; |
| 178 | } |
| 179 | *cp++ = '\0'; |
| 180 | strcpy(portbuf, cp); |
| 181 | h = buffer; |
| 182 | } else { |
| 183 | snprintf(portbuf, sizeof(portbuf), "%d", port); |
| 184 | h = host; |
| 185 | } |
| 186 | |
| 187 | memset(&hints, 0, sizeof(hints)); |
| 188 | hints.ai_family = af_hint; |
| 189 | hints.ai_socktype = type; |
| 190 | error = getaddrinfo(h, portbuf, &hints, &res0); |
| 191 | if (error) { |
| 192 | rprintf(FERROR, RSYNC_NAME ": getaddrinfo: %s %s: %s\n", |
| 193 | h, portbuf, gai_strerror(error)); |
| 194 | return -1; |
| 195 | } |
| 196 | |
| 197 | s = -1; |
| 198 | /* Try to connect to all addresses for this machine until we get |
| 199 | * through. It might e.g. be multi-homed, or have both IPv4 and IPv6 |
| 200 | * addresses. We need to create a socket for each record, since the |
| 201 | * address record tells us what protocol to use to try to connect. */ |
| 202 | for (res = res0; res; res = res->ai_next) { |
| 203 | s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); |
| 204 | if (s < 0) |
| 205 | continue; |
| 206 | |
| 207 | if (bind_address) |
| 208 | if (try_bind_local(s, res->ai_family, type, |
| 209 | bind_address) == -1) { |
| 210 | close(s); |
| 211 | s = -1; |
| 212 | continue; |
| 213 | } |
| 214 | |
| 215 | if (connect(s, res->ai_addr, res->ai_addrlen) < 0) { |
| 216 | close(s); |
| 217 | s = -1; |
| 218 | continue; |
| 219 | } |
| 220 | if (proxied && |
| 221 | establish_proxy_connection(s, host, port) != 0) { |
| 222 | close(s); |
| 223 | s = -1; |
| 224 | continue; |
| 225 | } else |
| 226 | break; |
| 227 | } |
| 228 | freeaddrinfo(res0); |
| 229 | if (s < 0) { |
| 230 | rprintf(FERROR, RSYNC_NAME ": failed to connect to %s: %s\n", |
| 231 | h, strerror(errno)); |
| 232 | return -1; |
| 233 | } |
| 234 | return s; |
| 235 | } |
| 236 | |
| 237 | |
| 238 | /** |
| 239 | * Open an outgoing socket, but allow for it to be intercepted by |
| 240 | * $RSYNC_CONNECT_PROG, which will execute a program across a TCP |
| 241 | * socketpair rather than really opening a socket. |
| 242 | * |
| 243 | * We use this primarily in testing to detect TCP flow bugs, but not |
| 244 | * cause security problems by really opening remote connections. |
| 245 | * |
| 246 | * This is based on the Samba LIBSMB_PROG feature. |
| 247 | * |
| 248 | * @param bind_address Local address to use. Normally NULL to get the stack default. |
| 249 | **/ |
| 250 | int open_socket_out_wrapped (char *host, |
| 251 | int port, |
| 252 | const char *bind_address, |
| 253 | int af_hint) |
| 254 | { |
| 255 | char *prog; |
| 256 | |
| 257 | if ((prog = getenv ("RSYNC_CONNECT_PROG")) != NULL) |
| 258 | return sock_exec (prog); |
| 259 | else |
| 260 | return open_socket_out (host, port, bind_address, |
| 261 | af_hint); |
| 262 | } |
| 263 | |
| 264 | |
| 265 | |
| 266 | /** |
| 267 | * Open a socket of the specified type, port and address for incoming data |
| 268 | * |
| 269 | * Try to be better about handling the results of getaddrinfo(): when |
| 270 | * opening an inbound socket, we might get several address results, |
| 271 | * e.g. for the machine's ipv4 and ipv6 name. |
| 272 | * |
| 273 | * If binding a wildcard, then any one of them should do. If an address |
| 274 | * was specified but it's insufficiently specific then that's not our |
| 275 | * fault. |
| 276 | * |
| 277 | * However, some of the advertized addresses may not work because e.g. we |
| 278 | * don't have IPv6 support in the kernel. In that case go on and try all |
| 279 | * addresses until one succeeds. |
| 280 | * |
| 281 | * @param bind_address Local address to bind, or NULL to allow it to |
| 282 | * default. |
| 283 | **/ |
| 284 | static int open_socket_in(int type, int port, const char *bind_address, |
| 285 | int af_hint) |
| 286 | { |
| 287 | int one=1; |
| 288 | int s; |
| 289 | struct addrinfo hints, *all_ai, *resp; |
| 290 | char portbuf[10]; |
| 291 | int error; |
| 292 | |
| 293 | memset(&hints, 0, sizeof(hints)); |
| 294 | hints.ai_family = af_hint; |
| 295 | hints.ai_socktype = type; |
| 296 | hints.ai_flags = AI_PASSIVE; |
| 297 | snprintf(portbuf, sizeof(portbuf), "%d", port); |
| 298 | error = getaddrinfo(bind_address, portbuf, &hints, &all_ai); |
| 299 | if (error) { |
| 300 | rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n", |
| 301 | bind_address, gai_strerror(error)); |
| 302 | return -1; |
| 303 | } |
| 304 | |
| 305 | /* We may not be able to create the socket, if for example the |
| 306 | * machine knows about IPv6 in the C library, but not in the |
| 307 | * kernel. */ |
| 308 | for (resp = all_ai; resp; resp = resp->ai_next) { |
| 309 | s = socket(resp->ai_family, resp->ai_socktype, |
| 310 | resp->ai_protocol); |
| 311 | |
| 312 | if (s == -1) |
| 313 | /* See if there's another address that will work... */ |
| 314 | continue; |
| 315 | |
| 316 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, |
| 317 | (char *)&one, sizeof one); |
| 318 | |
| 319 | /* now we've got a socket - we need to bind it */ |
| 320 | if (bind(s, all_ai->ai_addr, all_ai->ai_addrlen) < 0) { |
| 321 | /* Nope, try another */ |
| 322 | close(s); |
| 323 | continue; |
| 324 | } |
| 325 | |
| 326 | return s; |
| 327 | } |
| 328 | |
| 329 | rprintf(FERROR, RSYNC_NAME ": open inbound socket on port %d failed: " |
| 330 | "%s\n", |
| 331 | port, |
| 332 | strerror(errno)); |
| 333 | |
| 334 | freeaddrinfo(all_ai); |
| 335 | return -1; |
| 336 | } |
| 337 | |
| 338 | |
| 339 | /* |
| 340 | * Determine if a file descriptor is in fact a socket |
| 341 | */ |
| 342 | int is_a_socket(int fd) |
| 343 | { |
| 344 | int v; |
| 345 | socklen_t l; |
| 346 | l = sizeof(int); |
| 347 | |
| 348 | /* Parameters to getsockopt, setsockopt etc are very |
| 349 | * unstandardized across platforms, so don't be surprised if |
| 350 | * there are compiler warnings on e.g. SCO OpenSwerver or AIX. |
| 351 | * It seems they all eventually get the right idea. |
| 352 | * |
| 353 | * Debian says: ``The fifth argument of getsockopt and |
| 354 | * setsockopt is in reality an int [*] (and this is what BSD |
| 355 | * 4.* and libc4 and libc5 have). Some POSIX confusion |
| 356 | * resulted in the present socklen_t. The draft standard has |
| 357 | * not been adopted yet, but glibc2 already follows it and |
| 358 | * also has socklen_t [*]. See also accept(2).'' |
| 359 | * |
| 360 | * We now return to your regularly scheduled programming. */ |
| 361 | return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0); |
| 362 | } |
| 363 | |
| 364 | |
| 365 | void start_accept_loop(int port, int (*fn)(int )) |
| 366 | { |
| 367 | int s; |
| 368 | extern char *bind_address; |
| 369 | extern int default_af_hint; |
| 370 | |
| 371 | /* open an incoming socket */ |
| 372 | s = open_socket_in(SOCK_STREAM, port, bind_address, default_af_hint); |
| 373 | if (s == -1) |
| 374 | exit_cleanup(RERR_SOCKETIO); |
| 375 | |
| 376 | /* ready to listen */ |
| 377 | if (listen(s, 5) == -1) { |
| 378 | close(s); |
| 379 | exit_cleanup(RERR_SOCKETIO); |
| 380 | } |
| 381 | |
| 382 | |
| 383 | /* now accept incoming connections - forking a new process |
| 384 | for each incoming connection */ |
| 385 | while (1) { |
| 386 | fd_set fds; |
| 387 | int fd; |
| 388 | struct sockaddr_storage addr; |
| 389 | int addrlen = sizeof(addr); |
| 390 | |
| 391 | /* close log file before the potentially very long select so |
| 392 | file can be trimmed by another process instead of growing |
| 393 | forever */ |
| 394 | log_close(); |
| 395 | |
| 396 | FD_ZERO(&fds); |
| 397 | FD_SET(s, &fds); |
| 398 | |
| 399 | if (select(s+1, &fds, NULL, NULL, NULL) != 1) { |
| 400 | continue; |
| 401 | } |
| 402 | |
| 403 | if(!FD_ISSET(s, &fds)) continue; |
| 404 | |
| 405 | fd = accept(s,(struct sockaddr *)&addr,&addrlen); |
| 406 | |
| 407 | if (fd == -1) continue; |
| 408 | |
| 409 | signal(SIGCHLD, SIG_IGN); |
| 410 | |
| 411 | /* we shouldn't have any children left hanging around |
| 412 | but I have had reports that on Digital Unix zombies |
| 413 | are produced, so this ensures that they are reaped */ |
| 414 | #ifdef WNOHANG |
| 415 | while (waitpid(-1, NULL, WNOHANG) > 0); |
| 416 | #endif |
| 417 | |
| 418 | if (fork()==0) { |
| 419 | close(s); |
| 420 | /* open log file in child before possibly giving |
| 421 | up privileges */ |
| 422 | log_open(); |
| 423 | _exit(fn(fd)); |
| 424 | } |
| 425 | |
| 426 | close(fd); |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | |
| 431 | enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON}; |
| 432 | |
| 433 | struct |
| 434 | { |
| 435 | char *name; |
| 436 | int level; |
| 437 | int option; |
| 438 | int value; |
| 439 | int opttype; |
| 440 | } socket_options[] = { |
| 441 | {"SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE, 0, OPT_BOOL}, |
| 442 | {"SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR, 0, OPT_BOOL}, |
| 443 | {"SO_BROADCAST", SOL_SOCKET, SO_BROADCAST, 0, OPT_BOOL}, |
| 444 | #ifdef TCP_NODELAY |
| 445 | {"TCP_NODELAY", IPPROTO_TCP, TCP_NODELAY, 0, OPT_BOOL}, |
| 446 | #endif |
| 447 | #ifdef IPTOS_LOWDELAY |
| 448 | {"IPTOS_LOWDELAY", IPPROTO_IP, IP_TOS, IPTOS_LOWDELAY, OPT_ON}, |
| 449 | #endif |
| 450 | #ifdef IPTOS_THROUGHPUT |
| 451 | {"IPTOS_THROUGHPUT", IPPROTO_IP, IP_TOS, IPTOS_THROUGHPUT, OPT_ON}, |
| 452 | #endif |
| 453 | #ifdef SO_SNDBUF |
| 454 | {"SO_SNDBUF", SOL_SOCKET, SO_SNDBUF, 0, OPT_INT}, |
| 455 | #endif |
| 456 | #ifdef SO_RCVBUF |
| 457 | {"SO_RCVBUF", SOL_SOCKET, SO_RCVBUF, 0, OPT_INT}, |
| 458 | #endif |
| 459 | #ifdef SO_SNDLOWAT |
| 460 | {"SO_SNDLOWAT", SOL_SOCKET, SO_SNDLOWAT, 0, OPT_INT}, |
| 461 | #endif |
| 462 | #ifdef SO_RCVLOWAT |
| 463 | {"SO_RCVLOWAT", SOL_SOCKET, SO_RCVLOWAT, 0, OPT_INT}, |
| 464 | #endif |
| 465 | #ifdef SO_SNDTIMEO |
| 466 | {"SO_SNDTIMEO", SOL_SOCKET, SO_SNDTIMEO, 0, OPT_INT}, |
| 467 | #endif |
| 468 | #ifdef SO_RCVTIMEO |
| 469 | {"SO_RCVTIMEO", SOL_SOCKET, SO_RCVTIMEO, 0, OPT_INT}, |
| 470 | #endif |
| 471 | {NULL,0,0,0,0}}; |
| 472 | |
| 473 | |
| 474 | |
| 475 | /**************************************************************************** |
| 476 | set user socket options |
| 477 | ****************************************************************************/ |
| 478 | void set_socket_options(int fd, char *options) |
| 479 | { |
| 480 | char *tok; |
| 481 | if (!options || !*options) return; |
| 482 | |
| 483 | options = strdup(options); |
| 484 | |
| 485 | if (!options) out_of_memory("set_socket_options"); |
| 486 | |
| 487 | for (tok=strtok(options, " \t,"); tok; tok=strtok(NULL," \t,")) { |
| 488 | int ret=0,i; |
| 489 | int value = 1; |
| 490 | char *p; |
| 491 | int got_value = 0; |
| 492 | |
| 493 | if ((p = strchr(tok,'='))) { |
| 494 | *p = 0; |
| 495 | value = atoi(p+1); |
| 496 | got_value = 1; |
| 497 | } |
| 498 | |
| 499 | for (i=0;socket_options[i].name;i++) |
| 500 | if (strcmp(socket_options[i].name,tok)==0) |
| 501 | break; |
| 502 | |
| 503 | if (!socket_options[i].name) { |
| 504 | rprintf(FERROR,"Unknown socket option %s\n",tok); |
| 505 | continue; |
| 506 | } |
| 507 | |
| 508 | switch (socket_options[i].opttype) { |
| 509 | case OPT_BOOL: |
| 510 | case OPT_INT: |
| 511 | ret = setsockopt(fd,socket_options[i].level, |
| 512 | socket_options[i].option,(char *)&value,sizeof(int)); |
| 513 | break; |
| 514 | |
| 515 | case OPT_ON: |
| 516 | if (got_value) |
| 517 | rprintf(FERROR,"syntax error - %s does not take a value\n",tok); |
| 518 | |
| 519 | { |
| 520 | int on = socket_options[i].value; |
| 521 | ret = setsockopt(fd,socket_options[i].level, |
| 522 | socket_options[i].option,(char *)&on,sizeof(int)); |
| 523 | } |
| 524 | break; |
| 525 | } |
| 526 | |
| 527 | if (ret != 0) |
| 528 | rprintf(FERROR, "failed to set socket option %s: %s\n", tok, |
| 529 | strerror(errno)); |
| 530 | } |
| 531 | |
| 532 | free(options); |
| 533 | } |
| 534 | |
| 535 | /**************************************************************************** |
| 536 | become a daemon, discarding the controlling terminal |
| 537 | ****************************************************************************/ |
| 538 | void become_daemon(void) |
| 539 | { |
| 540 | int i; |
| 541 | |
| 542 | if (fork()) { |
| 543 | _exit(0); |
| 544 | } |
| 545 | |
| 546 | /* detach from the terminal */ |
| 547 | #ifdef HAVE_SETSID |
| 548 | setsid(); |
| 549 | #else |
| 550 | #ifdef TIOCNOTTY |
| 551 | i = open("/dev/tty", O_RDWR); |
| 552 | if (i >= 0) { |
| 553 | ioctl(i, (int) TIOCNOTTY, (char *)0); |
| 554 | close(i); |
| 555 | } |
| 556 | #endif /* TIOCNOTTY */ |
| 557 | #endif |
| 558 | /* make sure that stdin, stdout an stderr don't stuff things |
| 559 | up (library functions, for example) */ |
| 560 | for (i=0;i<3;i++) { |
| 561 | close(i); |
| 562 | open("/dev/null", O_RDWR); |
| 563 | } |
| 564 | } |
| 565 | |
| 566 | /** |
| 567 | * Return the IP addr of the client as a string |
| 568 | **/ |
| 569 | char *client_addr(int fd) |
| 570 | { |
| 571 | struct sockaddr_storage ss; |
| 572 | int length = sizeof(ss); |
| 573 | static char addr_buf[100]; |
| 574 | static int initialised; |
| 575 | |
| 576 | if (initialised) return addr_buf; |
| 577 | |
| 578 | initialised = 1; |
| 579 | |
| 580 | if (getpeername(fd, (struct sockaddr *)&ss, &length)) { |
| 581 | exit_cleanup(RERR_SOCKETIO); |
| 582 | } |
| 583 | |
| 584 | getnameinfo((struct sockaddr *)&ss, length, |
| 585 | addr_buf, sizeof(addr_buf), NULL, 0, NI_NUMERICHOST); |
| 586 | return addr_buf; |
| 587 | } |
| 588 | |
| 589 | |
| 590 | static int get_sockaddr_family(const struct sockaddr_storage *ss) |
| 591 | { |
| 592 | return ((struct sockaddr *) ss)->sa_family; |
| 593 | } |
| 594 | |
| 595 | |
| 596 | /** |
| 597 | * Return the DNS name of the client |
| 598 | **/ |
| 599 | char *client_name(int fd) |
| 600 | { |
| 601 | struct sockaddr_storage ss; |
| 602 | int length = sizeof(ss); |
| 603 | static char name_buf[100]; |
| 604 | static char port_buf[100]; |
| 605 | char *def = "UNKNOWN"; |
| 606 | static int initialised; |
| 607 | struct addrinfo hints, *res, *res0; |
| 608 | int error; |
| 609 | |
| 610 | if (initialised) return name_buf; |
| 611 | |
| 612 | initialised = 1; |
| 613 | |
| 614 | strcpy(name_buf,def); |
| 615 | |
| 616 | if (getpeername(fd, (struct sockaddr *)&ss, &length)) { |
| 617 | /* FIXME: Can we really not continue? */ |
| 618 | rprintf(FERROR, RSYNC_NAME ": getpeername on fd%d failed: %s\n", |
| 619 | fd, strerror(errno)); |
| 620 | exit_cleanup(RERR_SOCKETIO); |
| 621 | } |
| 622 | |
| 623 | #ifdef INET6 |
| 624 | if (get_sockaddr_family(&ss) == AF_INET6 && |
| 625 | IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&ss)->sin6_addr)) { |
| 626 | /* OK, so ss is in the IPv6 family, but it is really |
| 627 | * an IPv4 address: something like |
| 628 | * "::ffff:10.130.1.2". If we use it as-is, then the |
| 629 | * reverse lookup might fail or perhaps something else |
| 630 | * bad might happen. So instead we convert it to an |
| 631 | * equivalent address in the IPv4 address family. */ |
| 632 | struct sockaddr_in6 sin6; |
| 633 | struct sockaddr_in *sin; |
| 634 | |
| 635 | memcpy(&sin6, &ss, sizeof(sin6)); |
| 636 | sin = (struct sockaddr_in *)&ss; |
| 637 | memset(sin, 0, sizeof(*sin)); |
| 638 | sin->sin_family = AF_INET; |
| 639 | length = sizeof(struct sockaddr_in); |
| 640 | #ifdef HAVE_SOCKADDR_LEN |
| 641 | sin->sin_len = length; |
| 642 | #endif |
| 643 | sin->sin_port = sin6.sin6_port; |
| 644 | /* FIXME: Isn't there a macro we can use here rather |
| 645 | * than grovelling through the struct? It might be |
| 646 | * wrong on some systems. */ |
| 647 | memcpy(&sin->sin_addr, &sin6.sin6_addr.s6_addr[12], |
| 648 | sizeof(sin->sin_addr)); |
| 649 | } |
| 650 | #endif |
| 651 | |
| 652 | /* reverse lookup */ |
| 653 | if (getnameinfo((struct sockaddr *)&ss, length, |
| 654 | name_buf, sizeof(name_buf), port_buf, sizeof(port_buf), |
| 655 | NI_NAMEREQD | NI_NUMERICSERV) != 0) { |
| 656 | strcpy(name_buf, def); |
| 657 | rprintf(FERROR, "reverse name lookup failed\n"); |
| 658 | } |
| 659 | |
| 660 | /* forward lookup */ |
| 661 | memset(&hints, 0, sizeof(hints)); |
| 662 | hints.ai_family = PF_UNSPEC; |
| 663 | hints.ai_flags = AI_CANONNAME; |
| 664 | hints.ai_socktype = SOCK_STREAM; |
| 665 | error = getaddrinfo(name_buf, port_buf, &hints, &res0); |
| 666 | if (error) { |
| 667 | strcpy(name_buf, def); |
| 668 | rprintf(FERROR, |
| 669 | RSYNC_NAME ": forward name lookup for %s failed: %s\n", |
| 670 | port_buf, |
| 671 | gai_strerror(error)); |
| 672 | return name_buf; |
| 673 | } |
| 674 | |
| 675 | /* XXX sin6_flowinfo and other fields */ |
| 676 | for (res = res0; res; res = res->ai_next) { |
| 677 | if (res->ai_family != get_sockaddr_family(&ss)) |
| 678 | continue; |
| 679 | if (res->ai_addrlen != length) |
| 680 | continue; |
| 681 | if (memcmp(res->ai_addr, &ss, res->ai_addrlen) == 0) |
| 682 | break; |
| 683 | } |
| 684 | |
| 685 | if (res == NULL) { |
| 686 | strcpy(name_buf, def); |
| 687 | rprintf(FERROR, RSYNC_NAME ": " |
| 688 | "reverse name lookup for \"%s\" failed on fd%d - spoofed address? \n", |
| 689 | name_buf, fd); |
| 690 | } |
| 691 | |
| 692 | freeaddrinfo(res0); |
| 693 | return name_buf; |
| 694 | } |
| 695 | |
| 696 | |
| 697 | /******************************************************************* |
| 698 | this is like socketpair but uses tcp. It is used by the Samba |
| 699 | regression test code |
| 700 | The function guarantees that nobody else can attach to the socket, |
| 701 | or if they do that this function fails and the socket gets closed |
| 702 | returns 0 on success, -1 on failure |
| 703 | the resulting file descriptors are symmetrical |
| 704 | ******************************************************************/ |
| 705 | static int socketpair_tcp(int fd[2]) |
| 706 | { |
| 707 | int listener; |
| 708 | struct sockaddr_in sock; |
| 709 | struct sockaddr_in sock2; |
| 710 | socklen_t socklen = sizeof(sock); |
| 711 | int connect_done = 0; |
| 712 | |
| 713 | fd[0] = fd[1] = listener = -1; |
| 714 | |
| 715 | memset(&sock, 0, sizeof(sock)); |
| 716 | |
| 717 | if ((listener = socket(PF_INET, SOCK_STREAM, 0)) == -1) goto failed; |
| 718 | |
| 719 | memset(&sock2, 0, sizeof(sock2)); |
| 720 | #ifdef HAVE_SOCK_SIN_LEN |
| 721 | sock2.sin_len = sizeof(sock2); |
| 722 | #endif |
| 723 | sock2.sin_family = PF_INET; |
| 724 | |
| 725 | bind(listener, (struct sockaddr *)&sock2, sizeof(sock2)); |
| 726 | |
| 727 | if (listen(listener, 1) != 0) goto failed; |
| 728 | |
| 729 | if (getsockname(listener, (struct sockaddr *)&sock, &socklen) != 0) goto failed; |
| 730 | |
| 731 | if ((fd[1] = socket(PF_INET, SOCK_STREAM, 0)) == -1) goto failed; |
| 732 | |
| 733 | set_nonblocking(fd[1]); |
| 734 | |
| 735 | sock.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| 736 | |
| 737 | if (connect(fd[1],(struct sockaddr *)&sock,sizeof(sock)) == -1) { |
| 738 | if (errno != EINPROGRESS) goto failed; |
| 739 | } else { |
| 740 | connect_done = 1; |
| 741 | } |
| 742 | |
| 743 | if ((fd[0] = accept(listener, (struct sockaddr *)&sock, &socklen)) == -1) goto failed; |
| 744 | |
| 745 | close(listener); |
| 746 | if (connect_done == 0) { |
| 747 | if (connect(fd[1],(struct sockaddr *)&sock,sizeof(sock)) != 0 |
| 748 | && errno != EISCONN) goto failed; |
| 749 | } |
| 750 | |
| 751 | set_blocking (fd[1]); |
| 752 | |
| 753 | /* all OK! */ |
| 754 | return 0; |
| 755 | |
| 756 | failed: |
| 757 | if (fd[0] != -1) close(fd[0]); |
| 758 | if (fd[1] != -1) close(fd[1]); |
| 759 | if (listener != -1) close(listener); |
| 760 | return -1; |
| 761 | } |
| 762 | |
| 763 | |
| 764 | /******************************************************************* |
| 765 | run a program on a local tcp socket, this is used to launch smbd |
| 766 | when regression testing |
| 767 | the return value is a socket which is attached to a subprocess |
| 768 | running "prog". stdin and stdout are attached. stderr is left |
| 769 | attached to the original stderr |
| 770 | ******************************************************************/ |
| 771 | int sock_exec(const char *prog) |
| 772 | { |
| 773 | int fd[2]; |
| 774 | if (socketpair_tcp(fd) != 0) { |
| 775 | rprintf (FERROR, RSYNC_NAME |
| 776 | ": socketpair_tcp failed (%s)\n", |
| 777 | strerror(errno)); |
| 778 | return -1; |
| 779 | } |
| 780 | if (fork() == 0) { |
| 781 | close(fd[0]); |
| 782 | close(0); |
| 783 | close(1); |
| 784 | dup(fd[1]); |
| 785 | dup(fd[1]); |
| 786 | if (verbose > 3) |
| 787 | fprintf (stderr, |
| 788 | RSYNC_NAME ": execute socket program \"%s\"\n", |
| 789 | prog); |
| 790 | exit (system (prog)); |
| 791 | } |
| 792 | close (fd[1]); |
| 793 | return fd[0]; |
| 794 | } |
| 795 | |
| 796 | |
| 797 | |