1/* 2 * The socket based protocol for setting up a connection with rsyncd. 3 * 4 * Copyright (C) 1998-2001 Andrew Tridgell <tridge@samba.org> 5 * Copyright (C) 2001-2002 Martin Pool <mbp@samba.org> 6 * Copyright (C) 2002, 2003, 2004, 2005, 2006 Wayne Davison 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License along 19 * with this program; if not, write to the Free Software Foundation, Inc., 20 * 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. 21 */ 22 23#include "rsync.h" 24 25extern int verbose; 26extern int quiet; 27extern int output_motd; 28extern int list_only; 29extern int am_sender; 30extern int am_server; 31extern int am_daemon; 32extern int am_root; 33extern int rsync_port; 34extern int kluge_around_eof; 35extern int daemon_over_rsh; 36extern int sanitize_paths; 37extern int filesfrom_fd; 38extern int remote_protocol; 39extern int protocol_version; 40extern int io_timeout; 41extern int no_detach; 42extern int default_af_hint; 43extern int logfile_format_has_i; 44extern int logfile_format_has_o_or_i; 45extern mode_t orig_umask; 46extern char *bind_address; 47extern char *sockopts; 48extern char *config_file; 49extern char *logfile_format; 50extern char *files_from; 51extern char *tmpdir; 52extern struct chmod_mode_struct *chmod_modes; 53extern struct filter_list_struct server_filter_list; 54 55char *auth_user; 56int read_only = 0; 57int module_id = -1; 58int munge_symlinks = 0; 59struct chmod_mode_struct *daemon_chmod_modes; 60 61/* Length of lp_path() string when in daemon mode & not chrooted, else 0. */ 62unsigned int module_dirlen = 0; 63 64#ifdef HAVE_SIGACTION 65static struct sigaction sigact; 66#endif 67 68/** 69 * Run a client connected to an rsyncd. The alternative to this 70 * function for remote-shell connections is do_cmd(). 71 * 72 * After negotiating which module to use and reading the server's 73 * motd, this hands over to client_run(). Telling the server the 74 * module will cause it to chroot/setuid/etc. 75 * 76 * Instead of doing a transfer, the client may at this stage instead 77 * get a listing of remote modules and exit. 78 * 79 * @return -1 for error in startup, or the result of client_run(). 80 * Either way, it eventually gets passed to exit_cleanup(). 81 **/ 82int start_socket_client(char *host, char *path, int argc, char *argv[]) 83{ 84 int fd, ret; 85 char *p, *user = NULL; 86 87 /* This is redundant with code in start_inband_exchange(), but this 88 * short-circuits a problem in the client before we open a socket, 89 * and the extra check won't hurt. */ 90 if (*path == '/') { 91 rprintf(FERROR, 92 "ERROR: The remote path must start with a module name not a /\n"); 93 return -1; 94 } 95 96 if ((p = strrchr(host, '@')) != NULL) { 97 user = host; 98 host = p+1; 99 *p = '\0'; 100 } 101 102 fd = open_socket_out_wrapped(host, rsync_port, bind_address, 103 default_af_hint); 104 if (fd == -1) 105 exit_cleanup(RERR_SOCKETIO); 106 107 set_socket_options(fd, sockopts); 108 109 ret = start_inband_exchange(user, path, fd, fd, argc); 110 111 return ret ? ret : client_run(fd, fd, -1, argc, argv); 112} 113 114int start_inband_exchange(char *user, char *path, int f_in, int f_out, 115 int argc) 116{ 117 int i; 118 char *sargs[MAX_ARGS]; 119 int sargc = 0; 120 char line[BIGPATHBUFLEN]; 121 char *p; 122 123 if (argc == 0 && !am_sender) 124 list_only |= 1; 125 126 if (*path == '/') { 127 rprintf(FERROR, 128 "ERROR: The remote path must start with a module name\n"); 129 return -1; 130 } 131 132 if (!user) 133 user = getenv("USER"); 134 if (!user) 135 user = getenv("LOGNAME"); 136 137 io_printf(f_out, "@RSYNCD: %d\n", protocol_version); 138 139 if (!read_line(f_in, line, sizeof line - 1)) { 140 rprintf(FERROR, "rsync: did not see server greeting\n"); 141 return -1; 142 } 143 144 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) { 145 /* note that read_line strips of \n or \r */ 146 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", 147 line); 148 return -1; 149 } 150 if (protocol_version > remote_protocol) 151 protocol_version = remote_protocol; 152 153 if (list_only && protocol_version >= 29) 154 list_only |= 2; 155 156 /* set daemon_over_rsh to false since we need to build the 157 * true set of args passed through the rsh/ssh connection; 158 * this is a no-op for direct-socket-connection mode */ 159 daemon_over_rsh = 0; 160 server_options(sargs, &sargc); 161 162 sargs[sargc++] = "."; 163 164 if (path && *path) 165 sargs[sargc++] = path; 166 167 sargs[sargc] = NULL; 168 169 if (verbose > 1) 170 print_child_argv(sargs); 171 172 p = strchr(path,'/'); 173 if (p) *p = 0; 174 io_printf(f_out, "%s\n", path); 175 if (p) *p = '/'; 176 177 /* Old servers may just drop the connection here, 178 rather than sending a proper EXIT command. Yuck. */ 179 kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0; 180 181 while (1) { 182 if (!read_line(f_in, line, sizeof line - 1)) { 183 rprintf(FERROR, "rsync: didn't get server startup line\n"); 184 return -1; 185 } 186 187 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) { 188 auth_client(f_out, user, line+18); 189 continue; 190 } 191 192 if (strcmp(line,"@RSYNCD: OK") == 0) 193 break; 194 195 if (strcmp(line,"@RSYNCD: EXIT") == 0) { 196 /* This is sent by recent versions of the 197 * server to terminate the listing of modules. 198 * We don't want to go on and transfer 199 * anything; just exit. */ 200 exit(0); 201 } 202 203 if (strncmp(line, "@ERROR", 6) == 0) { 204 rprintf(FERROR, "%s\n", line); 205 /* This is always fatal; the server will now 206 * close the socket. */ 207 return -1; 208 } 209 210 /* This might be a MOTD line or a module listing, but there is 211 * no way to differentiate it. The manpage mentions this. */ 212 if (output_motd) 213 rprintf(FINFO, "%s\n", line); 214 } 215 kluge_around_eof = 0; 216 217 for (i = 0; i < sargc; i++) { 218 io_printf(f_out, "%s\n", sargs[i]); 219 } 220 io_printf(f_out, "\n"); 221 222 if (protocol_version < 23) { 223 if (protocol_version == 22 || !am_sender) 224 io_start_multiplex_in(); 225 } 226 227 return 0; 228} 229 230static char *finish_pre_exec(pid_t pid, int fd, char *request, 231 int argc, char *argv[]) 232{ 233 int j, status = -1; 234 235 if (request) { 236 write_buf(fd, request, strlen(request)+1); 237 for (j = 0; j < argc; j++) 238 write_buf(fd, argv[j], strlen(argv[j])+1); 239 } 240 241 write_byte(fd, 0); 242 243 close(fd); 244 245 if (wait_process(pid, &status, 0) < 0 246 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { 247 char *e; 248 if (asprintf(&e, "pre-xfer exec returned failure (%d)\n", status) < 0) 249 out_of_memory("finish_pre_exec"); 250 return e; 251 } 252 return NULL; 253} 254 255static int read_arg_from_pipe(int fd, char *buf, int limit) 256{ 257 char *bp = buf, *eob = buf + limit - 1; 258 259 while (1) { 260 if (read(fd, bp, 1) != 1) 261 return -1; 262 if (*bp == '\0') 263 break; 264 if (bp < eob) 265 bp++; 266 } 267 *bp = '\0'; 268 269 return bp - buf; 270} 271 272static int rsync_module(int f_in, int f_out, int i, char *addr, char *host) 273{ 274 int argc = 0; 275 int maxargs; 276 char **argv; 277 char line[BIGPATHBUFLEN]; 278 uid_t uid = (uid_t)-2; /* canonically "nobody" */ 279 gid_t gid = (gid_t)-2; 280 char *p, *err_msg = NULL; 281 char *name = lp_name(i); 282 int use_chroot = lp_use_chroot(i); 283 int start_glob = 0; 284 int ret, pre_exec_fd = -1; 285 pid_t pre_exec_pid = 0; 286 char *request = NULL; 287 288 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) { 289 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n", 290 name, host, addr); 291 if (!lp_list(i)) 292 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name); 293 else { 294 io_printf(f_out, 295 "@ERROR: access denied to %s from %s (%s)\n", 296 name, host, addr); 297 } 298 return -1; 299 } 300 301 if (am_daemon && am_server) { 302 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n", 303 name, host, addr); 304 } 305 306 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) { 307 if (errno) { 308 rsyserr(FLOG, errno, "failed to open lock file %s", 309 lp_lock_file(i)); 310 io_printf(f_out, "@ERROR: failed to open lock file\n"); 311 } else { 312 rprintf(FLOG, "max connections (%d) reached\n", 313 lp_max_connections(i)); 314 io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n", 315 lp_max_connections(i)); 316 } 317 return -1; 318 } 319 320 auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD "); 321 322 if (!auth_user) { 323 io_printf(f_out, "@ERROR: auth failed on module %s\n", name); 324 return -1; 325 } 326 327 module_id = i; 328 329 if (lp_read_only(i)) 330 read_only = 1; 331 332 if (lp_transfer_logging(i) && !logfile_format) 333 logfile_format = lp_log_format(i); 334 if (log_format_has(logfile_format, 'i')) 335 logfile_format_has_i = 1; 336 if (logfile_format_has_i || log_format_has(logfile_format, 'o')) 337 logfile_format_has_o_or_i = 1; 338 339 am_root = (MY_UID() == 0); 340 341 if (am_root) { 342 p = lp_uid(i); 343 if (!name_to_uid(p, &uid)) { 344 if (!isdigit(*(unsigned char *)p)) { 345 rprintf(FLOG, "Invalid uid %s\n", p); 346 io_printf(f_out, "@ERROR: invalid uid %s\n", p); 347 return -1; 348 } 349 uid = atoi(p); 350 } 351 352 p = lp_gid(i); 353 if (!name_to_gid(p, &gid)) { 354 if (!isdigit(*(unsigned char *)p)) { 355 rprintf(FLOG, "Invalid gid %s\n", p); 356 io_printf(f_out, "@ERROR: invalid gid %s\n", p); 357 return -1; 358 } 359 gid = atoi(p); 360 } 361 } 362 363 /* TODO: If we're not root, but the configuration requests 364 * that we change to some uid other than the current one, then 365 * log a warning. */ 366 367 /* TODO: Perhaps take a list of gids, and make them into the 368 * supplementary groups. */ 369 370 if (use_chroot || (module_dirlen = strlen(lp_path(i))) == 1) { 371 module_dirlen = 0; 372 set_filter_dir("/", 1); 373 } else 374 set_filter_dir(lp_path(i), module_dirlen); 375 376 p = lp_filter(i); 377 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT, 378 XFLG_ABS_IF_SLASH); 379 380 p = lp_include_from(i); 381 parse_filter_file(&server_filter_list, p, MATCHFLG_INCLUDE, 382 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS); 383 384 p = lp_include(i); 385 parse_rule(&server_filter_list, p, 386 MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT, 387 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES); 388 389 p = lp_exclude_from(i); 390 parse_filter_file(&server_filter_list, p, 0, 391 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS); 392 393 p = lp_exclude(i); 394 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT, 395 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES); 396 397 log_init(1); 398 399#ifdef HAVE_PUTENV 400 if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) { 401 char *modname, *modpath, *hostaddr, *hostname, *username; 402 int status; 403 if (asprintf(&modname, "RSYNC_MODULE_NAME=%s", name) < 0 404 || asprintf(&modpath, "RSYNC_MODULE_PATH=%s", lp_path(i)) < 0 405 || asprintf(&hostaddr, "RSYNC_HOST_ADDR=%s", addr) < 0 406 || asprintf(&hostname, "RSYNC_HOST_NAME=%s", host) < 0 407 || asprintf(&username, "RSYNC_USER_NAME=%s", auth_user) < 0) 408 out_of_memory("rsync_module"); 409 putenv(modname); 410 putenv(modpath); 411 putenv(hostaddr); 412 putenv(hostname); 413 putenv(username); 414 umask(orig_umask); 415 /* For post-xfer exec, fork a new process to run the rsync 416 * daemon while this process waits for the exit status and 417 * runs the indicated command at that point. */ 418 if (*lp_postxfer_exec(i)) { 419 pid_t pid = fork(); 420 if (pid < 0) { 421 rsyserr(FLOG, errno, "fork failed"); 422 io_printf(f_out, "@ERROR: fork failed\n"); 423 return -1; 424 } 425 if (pid) { 426 if (asprintf(&p, "RSYNC_PID=%ld", (long)pid) > 0) 427 putenv(p); 428 if (wait_process(pid, &status, 0) < 0) 429 status = -1; 430 if (asprintf(&p, "RSYNC_RAW_STATUS=%d", status) > 0) 431 putenv(p); 432 if (WIFEXITED(status)) 433 status = WEXITSTATUS(status); 434 else 435 status = -1; 436 if (asprintf(&p, "RSYNC_EXIT_STATUS=%d", status) > 0) 437 putenv(p); 438 system(lp_postxfer_exec(i)); 439 _exit(status); 440 } 441 } 442 /* For pre-xfer exec, fork a child process to run the indicated 443 * command, though it first waits for the parent process to 444 * send us the user's request via a pipe. */ 445 if (*lp_prexfer_exec(i)) { 446 int fds[2]; 447 if (asprintf(&p, "RSYNC_PID=%ld", (long)getpid()) > 0) 448 putenv(p); 449 if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) { 450 rsyserr(FLOG, errno, "pre-xfer exec preparation failed"); 451 io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n"); 452 return -1; 453 } 454 if (pre_exec_pid == 0) { 455 char buf[BIGPATHBUFLEN]; 456 int j, len; 457 close(fds[1]); 458 set_blocking(fds[0]); 459 len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN); 460 if (len <= 0) 461 _exit(1); 462 if (asprintf(&p, "RSYNC_REQUEST=%s", buf) > 0) 463 putenv(p); 464 for (j = 0; ; j++) { 465 len = read_arg_from_pipe(fds[0], buf, 466 BIGPATHBUFLEN); 467 if (len <= 0) { 468 if (!len) 469 break; 470 _exit(1); 471 } 472 if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) > 0) 473 putenv(p); 474 } 475 close(fds[0]); 476 close(STDIN_FILENO); 477 close(STDOUT_FILENO); 478 status = system(lp_prexfer_exec(i)); 479 if (!WIFEXITED(status)) 480 _exit(1); 481 _exit(WEXITSTATUS(status)); 482 } 483 close(fds[0]); 484 set_blocking(fds[1]); 485 pre_exec_fd = fds[1]; 486 } 487 umask(0); 488 } 489#endif 490 491 if (use_chroot) { 492 /* 493 * XXX: The 'use chroot' flag is a fairly reliable 494 * source of confusion, because it fails under two 495 * important circumstances: running as non-root, 496 * running on Win32 (or possibly others). On the 497 * other hand, if you are running as root, then it 498 * might be better to always use chroot. 499 * 500 * So, perhaps if we can't chroot we should just issue 501 * a warning, unless a "require chroot" flag is set, 502 * in which case we fail. 503 */ 504 if (chroot(lp_path(i))) { 505 rsyserr(FLOG, errno, "chroot %s failed", 506 lp_path(i)); 507 io_printf(f_out, "@ERROR: chroot failed\n"); 508 return -1; 509 } 510 511 if (!push_dir("/", 0)) { 512 rsyserr(FLOG, errno, "chdir %s failed\n", 513 lp_path(i)); 514 io_printf(f_out, "@ERROR: chdir failed\n"); 515 return -1; 516 } 517 518 } else { 519 if (!push_dir(lp_path(i), 0)) { 520 rsyserr(FLOG, errno, "chdir %s failed\n", 521 lp_path(i)); 522 io_printf(f_out, "@ERROR: chdir failed\n"); 523 return -1; 524 } 525 sanitize_paths = 1; 526 } 527 528 if ((munge_symlinks = lp_munge_symlinks(i)) < 0) 529 munge_symlinks = !use_chroot; 530 if (munge_symlinks) { 531 STRUCT_STAT st; 532 if (stat(SYMLINK_PREFIX, &st) == 0 && S_ISDIR(st.st_mode)) { 533 rprintf(FLOG, "Symlink munging is unsupported when a %s directory exists.\n", 534 SYMLINK_PREFIX); 535 io_printf(f_out, "@ERROR: daemon security issue -- contact admin\n", name); 536 exit_cleanup(RERR_UNSUPPORTED); 537 } 538 } 539 540 if (am_root) { 541 /* XXXX: You could argue that if the daemon is started 542 * by a non-root user and they explicitly specify a 543 * gid, then we should try to change to that gid -- 544 * this could be possible if it's already in their 545 * supplementary groups. */ 546 547 /* TODO: Perhaps we need to document that if rsyncd is 548 * started by somebody other than root it will inherit 549 * all their supplementary groups. */ 550 551 if (setgid(gid)) { 552 rsyserr(FLOG, errno, "setgid %d failed", (int)gid); 553 io_printf(f_out, "@ERROR: setgid failed\n"); 554 return -1; 555 } 556#ifdef HAVE_SETGROUPS 557 /* Get rid of any supplementary groups this process 558 * might have inheristed. */ 559 if (setgroups(1, &gid)) { 560 rsyserr(FLOG, errno, "setgroups failed"); 561 io_printf(f_out, "@ERROR: setgroups failed\n"); 562 return -1; 563 } 564#endif 565 566 if (setuid(uid)) { 567 rsyserr(FLOG, errno, "setuid %d failed", (int)uid); 568 io_printf(f_out, "@ERROR: setuid failed\n"); 569 return -1; 570 } 571 572 am_root = (MY_UID() == 0); 573 } 574 575 if (lp_temp_dir(i) && *lp_temp_dir(i)) { 576 tmpdir = lp_temp_dir(i); 577 if (strlen(tmpdir) >= MAXPATHLEN - 10) { 578 rprintf(FLOG, 579 "the 'temp dir' value for %s is WAY too long -- ignoring.\n", 580 name); 581 tmpdir = NULL; 582 } 583 } 584 585 io_printf(f_out, "@RSYNCD: OK\n"); 586 587 maxargs = MAX_ARGS; 588 if (!(argv = new_array(char *, maxargs))) 589 out_of_memory("rsync_module"); 590 argv[argc++] = "rsyncd"; 591 592 while (1) { 593 if (!read_line(f_in, line, sizeof line - 1)) 594 return -1; 595 596 if (!*line) 597 break; 598 599 p = line; 600 601 if (argc == maxargs) { 602 maxargs += MAX_ARGS; 603 if (!(argv = realloc_array(argv, char *, maxargs))) 604 out_of_memory("rsync_module"); 605 } 606 if (!(argv[argc] = strdup(p))) 607 out_of_memory("rsync_module"); 608 609 switch (start_glob) { 610 case 0: 611 argc++; 612 if (strcmp(line, ".") == 0) 613 start_glob = 1; 614 break; 615 case 1: 616 if (pre_exec_pid) { 617 err_msg = finish_pre_exec(pre_exec_pid, 618 pre_exec_fd, p, 619 argc, argv); 620 pre_exec_pid = 0; 621 } 622 request = strdup(p); 623 start_glob = 2; 624 /* FALL THROUGH */ 625 default: 626 if (!err_msg) 627 glob_expand(name, &argv, &argc, &maxargs); 628 break; 629 } 630 } 631 632 if (pre_exec_pid) { 633 err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request, 634 argc, argv); 635 } 636 637 verbose = 0; /* future verbosity is controlled by client options */ 638 ret = parse_arguments(&argc, (const char ***) &argv, 0); 639 quiet = 0; /* Don't let someone try to be tricky. */ 640 641 if (filesfrom_fd == 0) 642 filesfrom_fd = f_in; 643 644 if (request) { 645 if (*auth_user) { 646 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n", 647 am_sender ? "on" : "to", 648 request, auth_user, host, addr); 649 } else { 650 rprintf(FLOG, "rsync %s %s from %s (%s)\n", 651 am_sender ? "on" : "to", 652 request, host, addr); 653 } 654 free(request); 655 } 656 657#ifndef DEBUG 658 /* don't allow the logs to be flooded too fast */ 659 if (verbose > lp_max_verbosity(i)) 660 verbose = lp_max_verbosity(i); 661#endif 662 663 if (protocol_version < 23 664 && (protocol_version == 22 || am_sender)) 665 io_start_multiplex_out(); 666 else if (!ret || err_msg) { 667 /* We have to get I/O multiplexing started so that we can 668 * get the error back to the client. This means getting 669 * the protocol setup finished first in later versions. */ 670 setup_protocol(f_out, f_in); 671 if (!am_sender) { 672 /* Since we failed in our option parsing, we may not 673 * have finished parsing that the client sent us a 674 * --files-from option, so look for it manually. 675 * Without this, the socket would be in the wrong 676 * state for the upcoming error message. */ 677 if (!files_from) { 678 int i; 679 for (i = 0; i < argc; i++) { 680 if (strncmp(argv[i], "--files-from", 12) == 0) { 681 files_from = ""; 682 break; 683 } 684 } 685 } 686 if (files_from) 687 write_byte(f_out, 0); 688 } 689 io_start_multiplex_out(); 690 } 691 692 if (!ret || err_msg) { 693 if (err_msg) 694 rprintf(FERROR, "%s", err_msg); 695 else 696 option_error(); 697 msleep(400); 698 exit_cleanup(RERR_UNSUPPORTED); 699 } 700 701 if (lp_timeout(i) && lp_timeout(i) > io_timeout) 702 set_io_timeout(lp_timeout(i)); 703 704 /* If we have some incoming/outgoing chmod changes, append them to 705 * any user-specified changes (making our changes have priority). 706 * We also get a pointer to just our changes so that a receiver 707 * process can use them separately if --perms wasn't specified. */ 708 if (am_sender) 709 p = lp_outgoing_chmod(i); 710 else 711 p = lp_incoming_chmod(i); 712 if (*p && !(daemon_chmod_modes = parse_chmod(p, &chmod_modes))) { 713 rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n", 714 am_sender ? "outgo" : "incom", p); 715 } 716 717 start_server(f_in, f_out, argc, argv); 718 719 return 0; 720} 721 722/* send a list of available modules to the client. Don't list those 723 with "list = False". */ 724static void send_listing(int fd) 725{ 726 int n = lp_numservices(); 727 int i; 728 729 for (i = 0; i < n; i++) { 730 if (lp_list(i)) 731 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i)); 732 } 733 734 if (protocol_version >= 25) 735 io_printf(fd,"@RSYNCD: EXIT\n"); 736} 737 738/* this is called when a connection is established to a client 739 and we want to start talking. The setup of the system is done from 740 here */ 741int start_daemon(int f_in, int f_out) 742{ 743 char line[1024]; 744 char *motd, *addr, *host; 745 int i; 746 747 io_set_sock_fds(f_in, f_out); 748 749 /* We must load the config file before calling any function that 750 * might cause log-file output to occur. This ensures that the 751 * "log file" param gets honored for the 2 non-forked use-cases 752 * (when rsync is run by init and run by a remote shell). */ 753 if (!lp_load(config_file, 0)) 754 exit_cleanup(RERR_SYNTAX); 755 756 addr = client_addr(f_in); 757 host = client_name(f_in); 758 rprintf(FLOG, "connect from %s (%s)\n", host, addr); 759 760 if (!am_server) { 761 set_socket_options(f_in, "SO_KEEPALIVE"); 762 if (sockopts) 763 set_socket_options(f_in, sockopts); 764 else 765 set_socket_options(f_in, lp_socket_options()); 766 set_nonblocking(f_in); 767 } 768 769 io_printf(f_out, "@RSYNCD: %d\n", protocol_version); 770 771 motd = lp_motd_file(); 772 if (motd && *motd) { 773 FILE *f = fopen(motd,"r"); 774 while (f && !feof(f)) { 775 int len = fread(line, 1, sizeof line - 1, f); 776 if (len > 0) { 777 line[len] = 0; 778 io_printf(f_out, "%s", line); 779 } 780 } 781 if (f) 782 fclose(f); 783 io_printf(f_out, "\n"); 784 } 785 786 if (!read_line(f_in, line, sizeof line - 1)) 787 return -1; 788 789 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) { 790 io_printf(f_out, "@ERROR: protocol startup error\n"); 791 return -1; 792 } 793 if (protocol_version > remote_protocol) 794 protocol_version = remote_protocol; 795 796 line[0] = 0; 797 if (!read_line(f_in, line, sizeof line - 1)) 798 return -1; 799 800 if (!*line || strcmp(line, "#list") == 0) { 801 rprintf(FLOG, "module-list request from %s (%s)\n", 802 host, addr); 803 send_listing(f_out); 804 return -1; 805 } 806 807 if (*line == '#') { 808 /* it's some sort of command that I don't understand */ 809 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line); 810 return -1; 811 } 812 813 if ((i = lp_number(line)) < 0) { 814 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n", 815 line, host, addr); 816 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line); 817 return -1; 818 } 819 820#ifdef HAVE_SIGACTION 821 sigact.sa_flags = SA_NOCLDSTOP; 822#endif 823 SIGACTION(SIGCHLD, remember_children); 824 825 return rsync_module(f_in, f_out, i, addr, host); 826} 827 828int daemon_main(void) 829{ 830 char *pid_file; 831 832 if (is_a_socket(STDIN_FILENO)) { 833 int i; 834 835 /* we are running via inetd - close off stdout and 836 * stderr so that library functions (and getopt) don't 837 * try to use them. Redirect them to /dev/null */ 838 for (i = 1; i < 3; i++) { 839 close(i); 840 open("/dev/null", O_RDWR); 841 } 842 843 return start_daemon(STDIN_FILENO, STDIN_FILENO); 844 } 845 846 if (!no_detach) 847 become_daemon(); 848 849 if (!lp_load(config_file, 1)) 850 exit_cleanup(RERR_SYNTAX); 851 852 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0) 853 rsync_port = RSYNC_PORT; 854 if (bind_address == NULL && *lp_bind_address()) 855 bind_address = lp_bind_address(); 856 857 log_init(0); 858 859 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n", 860 RSYNC_VERSION, rsync_port); 861 /* TODO: If listening on a particular address, then show that 862 * address too. In fact, why not just do inet_ntop on the 863 * local address??? */ 864 865 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) { 866 char pidbuf[16]; 867 int fd; 868 pid_t pid = getpid(); 869 cleanup_set_pid(pid); 870 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC, 871 0666 & ~orig_umask)) == -1) { 872 cleanup_set_pid(0); 873 rsyserr(FLOG, errno, "failed to create pid file %s", 874 pid_file); 875 exit_cleanup(RERR_FILEIO); 876 } 877 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid); 878 write(fd, pidbuf, strlen(pidbuf)); 879 close(fd); 880 } 881 882 start_accept_loop(rsync_port, start_daemon); 883 return -1; 884} 885