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