2 * The socket based protocol for setting up a connection with rsyncd.
4 * Copyright (C) 1998-2001 Andrew Tridgell <tridge@samba.org>
5 * Copyright (C) 2001-2002 Martin Pool <mbp@samba.org>
6 * Copyright (C) 2002-2009 Wayne Davison
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 3 of the License, or
11 * (at your option) any later version.
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.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, visit the http://fsf.org website.
27 extern int output_motd;
33 extern int rsync_port;
34 extern int protect_args;
35 extern int ignore_errors;
36 extern int preserve_xattrs;
37 extern int kluge_around_eof;
38 extern int daemon_over_rsh;
39 extern int munge_symlinks;
40 extern int sanitize_paths;
41 extern int numeric_ids;
42 extern int filesfrom_fd;
43 extern int remote_protocol;
44 extern int protocol_version;
45 extern int io_timeout;
47 extern int write_batch;
48 extern int default_af_hint;
49 extern int logfile_format_has_i;
50 extern int logfile_format_has_o_or_i;
51 extern mode_t orig_umask;
52 extern char *bind_address;
53 extern char *config_file;
54 extern char *logfile_format;
55 extern char *files_from;
57 extern struct chmod_mode_struct *chmod_modes;
58 extern struct filter_list_struct daemon_filter_list;
59 extern char curr_dir[MAXPATHLEN];
61 extern char *iconv_opt;
62 extern iconv_t ic_send, ic_recv;
68 struct chmod_mode_struct *daemon_chmod_modes;
70 /* module_dirlen is the length of the module_dir string when in daemon
71 * mode and module_dir is not "/"; otherwise 0. (Note that a chroot-
72 * enabled module can have a non-"/" module_dir these days.) */
73 char *module_dir = NULL;
74 unsigned int module_dirlen = 0;
76 char *full_module_path;
78 static int rl_nulls = 0;
81 static struct sigaction sigact;
84 /* Used when "reverse lookup" is off. */
85 const char undetermined_hostname[] = "UNDETERMINED";
88 * Run a client connected to an rsyncd. The alternative to this
89 * function for remote-shell connections is do_cmd().
91 * After negotiating which module to use and reading the server's
92 * motd, this hands over to client_run(). Telling the server the
93 * module will cause it to chroot/setuid/etc.
95 * Instead of doing a transfer, the client may at this stage instead
96 * get a listing of remote modules and exit.
98 * @return -1 for error in startup, or the result of client_run().
99 * Either way, it eventually gets passed to exit_cleanup().
101 int start_socket_client(char *host, int remote_argc, char *remote_argv[],
102 int argc, char *argv[])
105 char *p, *user = NULL;
107 /* This is redundant with code in start_inband_exchange(), but this
108 * short-circuits a problem in the client before we open a socket,
109 * and the extra check won't hurt. */
110 if (**remote_argv == '/') {
112 "ERROR: The remote path must start with a module name not a /\n");
116 if ((p = strrchr(host, '@')) != NULL) {
122 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
125 exit_cleanup(RERR_SOCKETIO);
131 ret = start_inband_exchange(fd, fd, user, remote_argc, remote_argv);
133 return ret ? ret : client_run(fd, fd, -1, argc, argv);
136 static int exchange_protocols(int f_in, int f_out, char *buf, size_t bufsiz, int am_client)
139 #if SUBPROTOCOL_VERSION != 0
140 int our_sub = protocol_version < PROTOCOL_VERSION ? 0 : SUBPROTOCOL_VERSION;
146 io_printf(f_out, "@RSYNCD: %d.%d\n", protocol_version, our_sub);
149 motd = lp_motd_file();
151 FILE *f = fopen(motd,"r");
152 while (f && !feof(f)) {
153 int len = fread(buf, 1, bufsiz - 1, f);
155 write_buf(f_out, buf, len);
159 write_sbuf(f_out, "\n");
163 /* This strips the \n. */
164 if (!read_line_old(f_in, buf, bufsiz)) {
166 rprintf(FERROR, "rsync: did not see server greeting\n");
170 if (sscanf(buf, "@RSYNCD: %d.%d", &remote_protocol, &remote_sub) < 1) {
172 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", buf);
174 io_printf(f_out, "@ERROR: protocol startup error\n");
178 if (remote_sub < 0) {
179 if (remote_protocol == 30) {
181 rprintf(FERROR, "rsync: server is speaking an incompatible beta of protocol 30\n");
183 io_printf(f_out, "@ERROR: your client is speaking an incompatible beta of protocol 30\n");
189 if (protocol_version > remote_protocol) {
190 protocol_version = remote_protocol;
193 } else if (protocol_version == remote_protocol) {
194 if (remote_sub != our_sub)
197 #if SUBPROTOCOL_VERSION != 0
198 else if (protocol_version < remote_protocol) {
204 if (protocol_version >= 30)
210 int start_inband_exchange(int f_in, int f_out, const char *user, int argc, char *argv[])
213 char line[BIGPATHBUFLEN];
214 char *sargs[MAX_ARGS];
218 assert(argc > 0 && *argv != NULL);
222 "ERROR: The remote path must start with a module name\n");
226 if (!(p = strchr(*argv, '/')))
227 modlen = strlen(*argv);
231 if (!(modname = new_array(char, modlen+1+1))) /* room for '/' & '\0' */
232 out_of_memory("start_inband_exchange");
233 strlcpy(modname, *argv, modlen + 1);
234 modname[modlen] = '/';
235 modname[modlen+1] = '\0';
238 user = getenv("USER");
240 user = getenv("LOGNAME");
242 if (exchange_protocols(f_in, f_out, line, sizeof line, 1) < 0)
245 /* set daemon_over_rsh to false since we need to build the
246 * true set of args passed through the rsh/ssh connection;
247 * this is a no-op for direct-socket-connection mode */
249 server_options(sargs, &sargc);
251 if (sargc >= MAX_ARGS - 2)
254 sargs[sargc++] = ".";
257 if (sargc >= MAX_ARGS - 1) {
259 rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n");
260 exit_cleanup(RERR_SYNTAX);
262 if (strncmp(*argv, modname, modlen) == 0
263 && argv[0][modlen] == '\0')
264 sargs[sargc++] = modname; /* we send "modname/" */
266 sargs[sargc++] = *argv;
273 if (DEBUG_GTE(CMD, 1))
274 print_child_argv("sending daemon args:", sargs);
276 io_printf(f_out, "%.*s\n", modlen, modname);
278 /* Old servers may just drop the connection here,
279 rather than sending a proper EXIT command. Yuck. */
280 kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
283 if (!read_line_old(f_in, line, sizeof line)) {
284 rprintf(FERROR, "rsync: didn't get server startup line\n");
288 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
289 auth_client(f_out, user, line+18);
293 if (strcmp(line,"@RSYNCD: OK") == 0)
296 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
297 /* This is sent by recent versions of the
298 * server to terminate the listing of modules.
299 * We don't want to go on and transfer
300 * anything; just exit. */
304 if (strncmp(line, "@ERROR", 6) == 0) {
305 rprintf(FERROR, "%s\n", line);
306 /* This is always fatal; the server will now
307 * close the socket. */
311 /* This might be a MOTD line or a module listing, but there is
312 * no way to differentiate it. The manpage mentions this. */
314 rprintf(FINFO, "%s\n", line);
316 kluge_around_eof = 0;
319 for (i = 0; i < sargc; i++) {
320 if (!sargs[i]) /* stop at --protect-args NULL */
322 write_sbuf(f_out, sargs[i]);
323 write_byte(f_out, 0);
325 write_byte(f_out, 0);
327 for (i = 0; i < sargc; i++)
328 io_printf(f_out, "%s\n", sargs[i]);
329 write_sbuf(f_out, "\n");
333 send_protected_args(f_out, sargs);
335 if (protocol_version < 23) {
336 if (protocol_version == 22 || !am_sender)
337 io_start_multiplex_in();
345 static char *finish_pre_exec(pid_t pid, int fd, char *request,
346 char **early_argv, char **argv)
348 int j = 0, status = -1;
353 write_buf(fd, request, strlen(request)+1);
355 for ( ; *early_argv; early_argv++)
356 write_buf(fd, *early_argv, strlen(*early_argv)+1);
357 j = 1; /* Skip arg0 name in argv. */
359 for ( ; argv[j]; j++) {
360 write_buf(fd, argv[j], strlen(argv[j])+1);
361 if (argv[j][0] == '.' && argv[j][1] == '\0')
368 if (wait_process(pid, &status, 0) < 0
369 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
371 if (asprintf(&e, "pre-xfer exec returned failure (%d)%s%s\n",
372 status, status < 0 ? ": " : "",
373 status < 0 ? strerror(errno) : "") < 0)
374 out_of_memory("finish_pre_exec");
380 static int read_arg_from_pipe(int fd, char *buf, int limit)
382 char *bp = buf, *eob = buf + limit - 1;
385 int got = read(fd, bp, 1);
387 if (got < 0 && errno == EINTR)
401 static int path_failure(int f_out, const char *dir, BOOL was_chdir)
404 rsyserr(FLOG, errno, "chdir %s failed\n", dir);
406 rprintf(FLOG, "normalize_path(%s) failed\n", dir);
407 io_printf(f_out, "@ERROR: chdir failed\n");
411 static int rsync_module(int f_in, int f_out, int i, const char *addr, const char *host)
414 char **argv, **orig_argv, **orig_early_argv, *module_chdir;
415 char line[BIGPATHBUFLEN];
416 uid_t uid = (uid_t)-2; /* canonically "nobody" */
417 gid_t gid = (gid_t)-2;
418 char *p, *err_msg = NULL;
419 char *name = lp_name(i);
420 int use_chroot = lp_use_chroot(i);
421 int ret, pre_exec_fd = -1;
422 int save_munge_symlinks;
423 pid_t pre_exec_pid = 0;
424 char *request = NULL;
427 iconv_opt = lp_charset(i);
433 /* If reverse lookup is disabled globally but enabled for this module,
434 * we need to do it now before the access check. */
435 if (host == undetermined_hostname && lp_reverse_lookup(i))
436 host = client_name(f_in);
438 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
439 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
442 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
445 "@ERROR: access denied to %s from %s (%s)\n",
451 if (am_daemon && am_server) {
452 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
456 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
458 rsyserr(FLOG, errno, "failed to open lock file %s",
460 io_printf(f_out, "@ERROR: failed to open lock file\n");
462 rprintf(FLOG, "max connections (%d) reached\n",
463 lp_max_connections(i));
464 io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
465 lp_max_connections(i));
470 auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
473 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
482 if (lp_transfer_logging(i) && !logfile_format)
483 logfile_format = lp_log_format(i);
484 if (log_format_has(logfile_format, 'i'))
485 logfile_format_has_i = 1;
486 if (logfile_format_has_i || log_format_has(logfile_format, 'o'))
487 logfile_format_has_o_or_i = 1;
489 am_root = (MY_UID() == 0);
493 if (!name_to_uid(p, &uid)) {
495 rprintf(FLOG, "Invalid uid %s\n", p);
496 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
503 if (!name_to_gid(p, &gid)) {
505 rprintf(FLOG, "Invalid gid %s\n", p);
506 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
513 /* TODO: If we're not root, but the configuration requests
514 * that we change to some uid other than the current one, then
517 /* TODO: Perhaps take a list of gids, and make them into the
518 * supplementary groups. */
520 module_dir = lp_path(i);
522 if ((p = strstr(module_dir, "/./")) != NULL) {
523 *p = '\0'; /* Temporary... */
524 if (!(module_chdir = normalize_path(module_dir, True, NULL)))
525 return path_failure(f_out, module_dir, False);
527 if (!(p = normalize_path(p + 2, True, &module_dirlen)))
528 return path_failure(f_out, strstr(module_dir, "/./"), False);
529 if (!(full_module_path = normalize_path(module_dir, False, NULL)))
530 full_module_path = module_dir;
533 if (!(module_chdir = normalize_path(module_dir, False, NULL)))
534 return path_failure(f_out, module_dir, False);
535 full_module_path = module_chdir;
540 if (!(module_chdir = normalize_path(module_dir, False, &module_dirlen)))
541 return path_failure(f_out, module_dir, False);
542 full_module_path = module_dir = module_chdir;
545 if (module_dirlen == 1) {
547 set_filter_dir("/", 1);
549 set_filter_dir(module_dir, module_dirlen);
552 parse_rule(&daemon_filter_list, p, MATCHFLG_WORD_SPLIT,
553 XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3);
555 p = lp_include_from(i);
556 parse_filter_file(&daemon_filter_list, p, MATCHFLG_INCLUDE,
557 XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
560 parse_rule(&daemon_filter_list, p,
561 MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT,
562 XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES);
564 p = lp_exclude_from(i);
565 parse_filter_file(&daemon_filter_list, p, 0,
566 XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
569 parse_rule(&daemon_filter_list, p, MATCHFLG_WORD_SPLIT,
570 XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES);
575 if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) {
576 char *modname, *modpath, *hostaddr, *hostname, *username;
579 if (asprintf(&modname, "RSYNC_MODULE_NAME=%s", name) < 0
580 || asprintf(&modpath, "RSYNC_MODULE_PATH=%s", full_module_path) < 0
581 || asprintf(&hostaddr, "RSYNC_HOST_ADDR=%s", addr) < 0
582 || asprintf(&hostname, "RSYNC_HOST_NAME=%s", host) < 0
583 || asprintf(&username, "RSYNC_USER_NAME=%s", auth_user) < 0)
584 out_of_memory("rsync_module");
591 /* For post-xfer exec, fork a new process to run the rsync
592 * daemon while this process waits for the exit status and
593 * runs the indicated command at that point. */
594 if (*lp_postxfer_exec(i)) {
597 rsyserr(FLOG, errno, "fork failed");
598 io_printf(f_out, "@ERROR: fork failed\n");
602 if (asprintf(&p, "RSYNC_PID=%ld", (long)pid) > 0)
604 if (wait_process(pid, &status, 0) < 0)
606 if (asprintf(&p, "RSYNC_RAW_STATUS=%d", status) > 0)
608 if (WIFEXITED(status))
609 status = WEXITSTATUS(status);
612 if (asprintf(&p, "RSYNC_EXIT_STATUS=%d", status) > 0)
614 if (system(lp_postxfer_exec(i)) < 0)
619 /* For pre-xfer exec, fork a child process to run the indicated
620 * command, though it first waits for the parent process to
621 * send us the user's request via a pipe. */
622 if (*lp_prexfer_exec(i)) {
624 if (asprintf(&p, "RSYNC_PID=%ld", (long)getpid()) > 0)
626 if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) {
627 rsyserr(FLOG, errno, "pre-xfer exec preparation failed");
628 io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n");
631 if (pre_exec_pid == 0) {
632 char buf[BIGPATHBUFLEN];
635 set_blocking(fds[0]);
636 len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN);
639 if (asprintf(&p, "RSYNC_REQUEST=%s", buf) > 0)
642 len = read_arg_from_pipe(fds[0], buf,
649 if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) > 0)
654 close(STDOUT_FILENO);
655 status = system(lp_prexfer_exec(i));
656 if (!WIFEXITED(status))
658 _exit(WEXITSTATUS(status));
661 set_blocking(fds[1]);
662 pre_exec_fd = fds[1];
670 * XXX: The 'use chroot' flag is a fairly reliable
671 * source of confusion, because it fails under two
672 * important circumstances: running as non-root,
673 * running on Win32 (or possibly others). On the
674 * other hand, if you are running as root, then it
675 * might be better to always use chroot.
677 * So, perhaps if we can't chroot we should just issue
678 * a warning, unless a "require chroot" flag is set,
679 * in which case we fail.
681 if (chroot(module_chdir)) {
682 rsyserr(FLOG, errno, "chroot %s failed", module_chdir);
683 io_printf(f_out, "@ERROR: chroot failed\n");
686 module_chdir = module_dir;
689 if (!change_dir(module_chdir, CD_NORMAL))
690 return path_failure(f_out, module_chdir, True);
691 if (module_dirlen || !use_chroot)
694 if ((munge_symlinks = lp_munge_symlinks(i)) < 0)
695 munge_symlinks = !use_chroot || module_dirlen;
696 if (munge_symlinks) {
698 char prefix[SYMLINK_PREFIX_LEN]; /* NOT +1 ! */
699 strlcpy(prefix, SYMLINK_PREFIX, sizeof prefix); /* trim the trailing slash */
700 if (do_stat(prefix, &st) == 0 && S_ISDIR(st.st_mode)) {
701 rprintf(FLOG, "Symlink munging is unsafe when a %s directory exists.\n",
703 io_printf(f_out, "@ERROR: daemon security issue -- contact admin\n", name);
704 exit_cleanup(RERR_UNSUPPORTED);
709 /* XXXX: You could argue that if the daemon is started
710 * by a non-root user and they explicitly specify a
711 * gid, then we should try to change to that gid --
712 * this could be possible if it's already in their
713 * supplementary groups. */
715 /* TODO: Perhaps we need to document that if rsyncd is
716 * started by somebody other than root it will inherit
717 * all their supplementary groups. */
720 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
721 io_printf(f_out, "@ERROR: setgid failed\n");
724 #ifdef HAVE_SETGROUPS
725 /* Get rid of any supplementary groups this process
726 * might have inheristed. */
727 if (setgroups(1, &gid)) {
728 rsyserr(FLOG, errno, "setgroups failed");
729 io_printf(f_out, "@ERROR: setgroups failed\n");
735 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
736 io_printf(f_out, "@ERROR: setuid failed\n");
740 am_root = (MY_UID() == 0);
743 if (lp_temp_dir(i) && *lp_temp_dir(i)) {
744 tmpdir = lp_temp_dir(i);
745 if (strlen(tmpdir) >= MAXPATHLEN - 10) {
747 "the 'temp dir' value for %s is WAY too long -- ignoring.\n",
753 io_printf(f_out, "@RSYNCD: OK\n");
755 read_args(f_in, name, line, sizeof line, rl_nulls, &argv, &argc, &request);
758 save_munge_symlinks = munge_symlinks;
760 reset_output_levels(); /* future verbosity is controlled by client options */
761 ret = parse_arguments(&argc, (const char ***) &argv);
762 if (protect_args && ret) {
763 orig_early_argv = orig_argv;
765 read_args(f_in, name, line, sizeof line, 1, &argv, &argc, &request);
767 ret = parse_arguments(&argc, (const char ***) &argv);
769 orig_early_argv = NULL;
771 munge_symlinks = save_munge_symlinks; /* The client mustn't control this. */
774 err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request,
775 orig_early_argv, orig_argv);
779 free(orig_early_argv);
781 am_server = 1; /* Don't let someone try to be tricky. */
783 if (lp_ignore_errors(module_id))
788 if (lp_fake_super(i)) {
789 if (preserve_xattrs > 1)
792 } else if (am_root < 0) /* Treat --fake-super from client as --super. */
795 if (filesfrom_fd == 0)
800 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
801 am_sender ? "on" : "to",
802 request, auth_user, host, addr);
804 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
805 am_sender ? "on" : "to",
806 request, host, addr);
812 /* don't allow the logs to be flooded too fast */
813 limit_output_verbosity(lp_max_verbosity(i));
816 if (protocol_version < 23
817 && (protocol_version == 22 || am_sender))
818 io_start_multiplex_out();
819 else if (!ret || err_msg) {
820 /* We have to get I/O multiplexing started so that we can
821 * get the error back to the client. This means getting
822 * the protocol setup finished first in later versions. */
823 setup_protocol(f_out, f_in);
825 /* Since we failed in our option parsing, we may not
826 * have finished parsing that the client sent us a
827 * --files-from option, so look for it manually.
828 * Without this, the socket would be in the wrong
829 * state for the upcoming error message. */
832 for (i = 0; i < argc; i++) {
833 if (strncmp(argv[i], "--files-from", 12) == 0) {
840 write_byte(f_out, 0);
842 io_start_multiplex_out();
845 if (!ret || err_msg) {
847 rwrite(FERROR, err_msg, strlen(err_msg), 0);
851 exit_cleanup(RERR_UNSUPPORTED);
856 if (ic_send != (iconv_t)-1) {
857 iconv_close(ic_send);
858 ic_send = (iconv_t)-1;
860 if (ic_recv != (iconv_t)-1) {
861 iconv_close(ic_recv);
862 ic_recv = (iconv_t)-1;
868 && (use_chroot ? lp_numeric_ids(i) != False : lp_numeric_ids(i) == True))
869 numeric_ids = -1; /* Set --numeric-ids w/o breaking protocol. */
871 if (lp_timeout(i) && lp_timeout(i) > io_timeout)
872 set_io_timeout(lp_timeout(i));
874 /* If we have some incoming/outgoing chmod changes, append them to
875 * any user-specified changes (making our changes have priority).
876 * We also get a pointer to just our changes so that a receiver
877 * process can use them separately if --perms wasn't specified. */
879 p = lp_outgoing_chmod(i);
881 p = lp_incoming_chmod(i);
882 if (*p && !(daemon_chmod_modes = parse_chmod(p, &chmod_modes))) {
883 rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n",
884 am_sender ? "outgo" : "incom", p);
887 start_server(f_in, f_out, argc, argv);
892 /* send a list of available modules to the client. Don't list those
893 with "list = False". */
894 static void send_listing(int fd)
896 int n = lp_num_modules();
899 for (i = 0; i < n; i++) {
901 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
904 if (protocol_version >= 25)
905 io_printf(fd,"@RSYNCD: EXIT\n");
908 static int load_config(int globals_only)
911 if (am_server && am_root <= 0)
912 config_file = RSYNCD_USERCONF;
914 config_file = RSYNCD_SYSCONF;
916 return lp_load(config_file, globals_only);
919 /* this is called when a connection is established to a client
920 and we want to start talking. The setup of the system is done from
922 int start_daemon(int f_in, int f_out)
925 const char *addr, *host;
928 io_set_sock_fds(f_in, f_out);
930 /* We must load the config file before calling any function that
931 * might cause log-file output to occur. This ensures that the
932 * "log file" param gets honored for the 2 non-forked use-cases
933 * (when rsync is run by init and run by a remote shell). */
935 exit_cleanup(RERR_SYNTAX);
937 addr = client_addr(f_in);
938 host = lp_reverse_lookup(-1) ? client_name(f_in) : undetermined_hostname;
939 rprintf(FLOG, "connect from %s (%s)\n", host, addr);
942 set_socket_options(f_in, "SO_KEEPALIVE");
943 set_nonblocking(f_in);
946 if (exchange_protocols(f_in, f_out, line, sizeof line, 0) < 0)
950 if (!read_line_old(f_in, line, sizeof line))
953 if (!*line || strcmp(line, "#list") == 0) {
954 rprintf(FLOG, "module-list request from %s (%s)\n",
961 /* it's some sort of command that I don't understand */
962 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
966 if ((i = lp_number(line)) < 0) {
967 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
969 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
973 #ifdef HAVE_SIGACTION
974 sigact.sa_flags = SA_NOCLDSTOP;
976 SIGACTION(SIGCHLD, remember_children);
978 return rsync_module(f_in, f_out, i, addr, host);
981 static void create_pid_file(void)
983 char *pid_file = lp_pid_file();
985 pid_t pid = getpid();
988 if (!pid_file || !*pid_file)
991 cleanup_set_pid(pid);
992 if ((fd = do_open(pid_file, O_WRONLY|O_CREAT|O_EXCL, 0666 & ~orig_umask)) == -1) {
995 fprintf(stderr, "failed to create pid file %s: %s\n", pid_file, strerror(errno));
996 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
997 exit_cleanup(RERR_FILEIO);
999 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
1000 len = strlen(pidbuf);
1001 if (write(fd, pidbuf, len) != len)
1006 /* Become a daemon, discarding the controlling terminal. */
1007 static void become_daemon(void)
1014 fprintf(stderr, "failed to fork: %s\n", strerror(errno));
1015 exit_cleanup(RERR_FILEIO);
1022 /* detach from the terminal */
1025 #elif defined TIOCNOTTY
1026 i = open("/dev/tty", O_RDWR);
1028 ioctl(i, (int)TIOCNOTTY, (char *)0);
1032 /* make sure that stdin, stdout an stderr don't stuff things
1033 * up (library functions, for example) */
1034 for (i = 0; i < 3; i++) {
1036 open("/dev/null", O_RDWR);
1040 int daemon_main(void)
1042 if (is_a_socket(STDIN_FILENO)) {
1045 /* we are running via inetd - close off stdout and
1046 * stderr so that library functions (and getopt) don't
1047 * try to use them. Redirect them to /dev/null */
1048 for (i = 1; i < 3; i++) {
1050 open("/dev/null", O_RDWR);
1053 return start_daemon(STDIN_FILENO, STDIN_FILENO);
1056 if (!load_config(1)) {
1057 fprintf(stderr, "Failed to parse config file: %s\n", config_file);
1058 exit_cleanup(RERR_SYNTAX);
1067 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
1068 rsync_port = RSYNC_PORT;
1069 if (bind_address == NULL && *lp_bind_address())
1070 bind_address = lp_bind_address();
1074 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
1075 RSYNC_VERSION, rsync_port);
1076 /* TODO: If listening on a particular address, then show that
1077 * address too. In fact, why not just do inet_ntop on the
1078 * local address??? */
1080 start_accept_loop(rsync_port, start_daemon);