1 /* -*- c-file-style: "linux"; -*-
3 * Copyright (C) 1998-2001 by Andrew Tridgell <tridge@samba.org>
4 * Copyright (C) 2001-2002 by Martin Pool <mbp@samba.org>
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.
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.
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.
24 * The socket based protocol for setting up a connection with
37 extern int rsync_port;
38 extern int kluge_around_eof;
39 extern int daemon_over_rsh;
40 extern int sanitize_paths;
41 extern int filesfrom_fd;
42 extern int remote_protocol;
43 extern int protocol_version;
44 extern int io_timeout;
46 extern int default_af_hint;
47 extern mode_t orig_umask;
48 extern char *bind_address;
49 extern char *sockopts;
50 extern char *config_file;
51 extern char *files_from;
53 extern struct chmod_mode_struct *chmod_modes;
54 extern struct filter_list_struct server_filter_list;
58 int daemon_log_format_has_i = 0;
59 int daemon_log_format_has_o_or_i = 0;
61 struct chmod_mode_struct *daemon_chmod_modes;
63 /* Length of lp_path() string when in daemon mode & not chrooted, else 0. */
64 unsigned int module_dirlen = 0;
67 static struct sigaction sigact;
71 * Run a client connected to an rsyncd. The alternative to this
72 * function for remote-shell connections is do_cmd().
74 * After negotiating which module to use and reading the server's
75 * motd, this hands over to client_run(). Telling the server the
76 * module will cause it to chroot/setuid/etc.
78 * Instead of doing a transfer, the client may at this stage instead
79 * get a listing of remote modules and exit.
81 * @return -1 for error in startup, or the result of client_run().
82 * Either way, it eventually gets passed to exit_cleanup().
84 int start_socket_client(char *host, char *path, int argc, char *argv[])
87 char *p, *user = NULL;
89 /* This is redundant with code in start_inband_exchange(), but this
90 * short-circuits a problem in the client before we open a socket,
91 * and the extra check won't hurt. */
94 "ERROR: The remote path must start with a module name not a /\n");
98 if ((p = strrchr(host, '@')) != NULL) {
104 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
107 exit_cleanup(RERR_SOCKETIO);
109 set_socket_options(fd, sockopts);
111 ret = start_inband_exchange(user, path, fd, fd, argc);
113 return ret ? ret : client_run(fd, fd, -1, argc, argv);
116 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
120 char *sargs[MAX_ARGS];
122 char line[BIGPATHBUFLEN];
125 if (argc == 0 && !am_sender)
130 "ERROR: The remote path must start with a module name\n");
135 user = getenv("USER");
137 user = getenv("LOGNAME");
139 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
141 if (!read_line(f_in, line, sizeof line - 1)) {
142 rprintf(FERROR, "rsync: did not see server greeting\n");
146 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
147 /* note that read_line strips of \n or \r */
148 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
152 if (protocol_version > remote_protocol)
153 protocol_version = remote_protocol;
155 if (list_only && protocol_version >= 29)
158 /* set daemon_over_rsh to false since we need to build the
159 * true set of args passed through the rsh/ssh connection;
160 * this is a no-op for direct-socket-connection mode */
162 server_options(sargs, &sargc);
164 sargs[sargc++] = ".";
167 sargs[sargc++] = path;
172 print_child_argv(sargs);
174 p = strchr(path,'/');
176 io_printf(f_out, "%s\n", path);
179 /* Old servers may just drop the connection here,
180 rather than sending a proper EXIT command. Yuck. */
181 kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
184 if (!read_line(f_in, line, sizeof line - 1)) {
185 rprintf(FERROR, "rsync: didn't get server startup line\n");
189 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
190 auth_client(f_out, user, line+18);
194 if (strcmp(line,"@RSYNCD: OK") == 0)
197 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
198 /* This is sent by recent versions of the
199 * server to terminate the listing of modules.
200 * We don't want to go on and transfer
201 * anything; just exit. */
205 if (strncmp(line, "@ERROR", 6) == 0) {
206 rprintf(FERROR, "%s\n", line);
207 /* This is always fatal; the server will now
208 * close the socket. */
212 rprintf(FINFO, "%s\n", line);
214 kluge_around_eof = 0;
216 for (i = 0; i < sargc; i++) {
217 io_printf(f_out, "%s\n", sargs[i]);
219 io_printf(f_out, "\n");
221 if (protocol_version < 23) {
222 if (protocol_version == 22 || !am_sender)
223 io_start_multiplex_in();
229 static char *finish_pre_exec(pid_t pid, int fd, char *request,
230 int argc, char *argv[])
235 write_buf(fd, request, strlen(request)+1);
236 for (j = 0; j < argc; j++)
237 write_buf(fd, argv[j], strlen(argv[j])+1);
244 if (wait_process(pid, &status, 0) < 0
245 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
247 if (asprintf(&e, "pre-xfer exec returned failure (%d)\n", status) < 0)
248 out_of_memory("finish_pre_exec");
254 static int read_arg_from_pipe(int fd, char *buf, int limit)
256 char *bp = buf, *eob = buf + limit - 1;
259 if (read(fd, bp, 1) != 1)
271 static int rsync_module(int f_in, int f_out, int i, char *addr, char *host)
276 char line[BIGPATHBUFLEN];
277 uid_t uid = (uid_t)-2; /* canonically "nobody" */
278 gid_t gid = (gid_t)-2;
279 char *p, *err_msg = NULL;
280 char *name = lp_name(i);
281 int use_chroot = lp_use_chroot(i);
283 int ret, pre_exec_fd = -1;
284 pid_t pre_exec_pid = 0;
285 char *request = NULL;
287 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
288 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
291 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
294 "@ERROR: access denied to %s from %s (%s)\n",
300 if (am_daemon && am_server) {
301 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
305 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
307 rsyserr(FLOG, errno, "failed to open lock file %s",
309 io_printf(f_out, "@ERROR: failed to open lock file\n");
311 rprintf(FLOG, "max connections (%d) reached\n",
312 lp_max_connections(i));
313 io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
314 lp_max_connections(i));
319 auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
322 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
331 if (lp_transfer_logging(i)) {
332 if (log_format_has(lp_log_format(i), 'i'))
333 daemon_log_format_has_i = 1;
334 if (daemon_log_format_has_i
335 || log_format_has(lp_log_format(i), 'o'))
336 daemon_log_format_has_o_or_i = 1;
339 am_root = (MY_UID() == 0);
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);
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);
363 /* TODO: If we're not root, but the configuration requests
364 * that we change to some uid other than the current one, then
367 /* TODO: Perhaps take a list of gids, and make them into the
368 * supplementary groups. */
370 if (use_chroot || (module_dirlen = strlen(lp_path(i))) == 1) {
372 set_filter_dir("/", 1);
374 set_filter_dir(lp_path(i), module_dirlen);
377 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
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);
385 parse_rule(&server_filter_list, p,
386 MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT,
387 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES);
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);
394 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
395 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES);
400 if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) {
401 char *modname, *modpath, *hostaddr, *hostname, *username;
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");
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)) {
421 rsyserr(FLOG, errno, "fork failed");
422 io_printf(f_out, "@ERROR: fork failed\n");
427 if (wait_process(pid, &status, 0) < 0)
429 if (asprintf(&ret1, "RSYNC_RAW_STATUS=%d", status) > 0)
431 if (WIFEXITED(status))
432 status = WEXITSTATUS(status);
435 if (asprintf(&ret2, "RSYNC_EXIT_STATUS=%d", status) > 0)
437 system(lp_postxfer_exec(i));
441 /* For pre-xfer exec, fork a child process to run the indicated
442 * command, though it first waits for the parent process to
443 * send us the user's request via a pipe. */
444 if (*lp_prexfer_exec(i)) {
446 if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) {
447 rsyserr(FLOG, errno, "pre-xfer exec preparation failed");
448 io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n");
451 if (pre_exec_pid == 0) {
452 char buf[BIGPATHBUFLEN];
455 set_blocking(fds[0]);
456 len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN);
459 if (asprintf(&p, "RSYNC_REQUEST=%s", buf) < 0)
460 out_of_memory("rsync_module");
463 len = read_arg_from_pipe(fds[0], buf,
470 if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) < 0)
471 out_of_memory("rsync_module");
476 close(STDOUT_FILENO);
477 status = system(lp_prexfer_exec(i));
478 if (!WIFEXITED(status))
480 _exit(WEXITSTATUS(status));
483 set_blocking(fds[1]);
484 pre_exec_fd = fds[1];
492 * XXX: The 'use chroot' flag is a fairly reliable
493 * source of confusion, because it fails under two
494 * important circumstances: running as non-root,
495 * running on Win32 (or possibly others). On the
496 * other hand, if you are running as root, then it
497 * might be better to always use chroot.
499 * So, perhaps if we can't chroot we should just issue
500 * a warning, unless a "require chroot" flag is set,
501 * in which case we fail.
503 if (chroot(lp_path(i))) {
504 rsyserr(FLOG, errno, "chroot %s failed",
506 io_printf(f_out, "@ERROR: chroot failed\n");
510 if (!push_dir("/")) {
511 rsyserr(FLOG, errno, "chdir %s failed\n",
513 io_printf(f_out, "@ERROR: chdir failed\n");
518 if (!push_dir(lp_path(i))) {
519 rsyserr(FLOG, errno, "chdir %s failed\n",
521 io_printf(f_out, "@ERROR: chdir failed\n");
528 /* XXXX: You could argue that if the daemon is started
529 * by a non-root user and they explicitly specify a
530 * gid, then we should try to change to that gid --
531 * this could be possible if it's already in their
532 * supplementary groups. */
534 /* TODO: Perhaps we need to document that if rsyncd is
535 * started by somebody other than root it will inherit
536 * all their supplementary groups. */
539 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
540 io_printf(f_out, "@ERROR: setgid failed\n");
543 #ifdef HAVE_SETGROUPS
544 /* Get rid of any supplementary groups this process
545 * might have inheristed. */
546 if (setgroups(1, &gid)) {
547 rsyserr(FLOG, errno, "setgroups failed");
548 io_printf(f_out, "@ERROR: setgroups failed\n");
554 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
555 io_printf(f_out, "@ERROR: setuid failed\n");
559 am_root = (MY_UID() == 0);
562 if (lp_temp_dir(i) && *lp_temp_dir(i)) {
563 tmpdir = lp_temp_dir(i);
564 if (strlen(tmpdir) >= MAXPATHLEN - 10) {
566 "the 'temp dir' value for %s is WAY too long -- ignoring.\n",
572 io_printf(f_out, "@RSYNCD: OK\n");
575 if (!(argv = new_array(char *, maxargs)))
576 out_of_memory("rsync_module");
577 argv[argc++] = "rsyncd";
580 if (!read_line(f_in, line, sizeof line - 1))
588 if (argc == maxargs) {
590 if (!(argv = realloc_array(argv, char *, maxargs)))
591 out_of_memory("rsync_module");
593 if (!(argv[argc] = strdup(p)))
594 out_of_memory("rsync_module");
596 switch (start_glob) {
599 if (strcmp(line, ".") == 0)
604 err_msg = finish_pre_exec(pre_exec_pid,
614 glob_expand(name, &argv, &argc, &maxargs);
620 err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request,
624 verbose = 0; /* future verbosity is controlled by client options */
625 ret = parse_arguments(&argc, (const char ***) &argv, 0);
626 quiet = 0; /* Don't let someone try to be tricky. */
628 if (filesfrom_fd == 0)
633 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
634 am_sender ? "on" : "to",
635 request, auth_user, host, addr);
637 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
638 am_sender ? "on" : "to",
639 request, host, addr);
645 /* don't allow the logs to be flooded too fast */
646 if (verbose > lp_max_verbosity(i))
647 verbose = lp_max_verbosity(i);
650 if (protocol_version < 23
651 && (protocol_version == 22 || am_sender))
652 io_start_multiplex_out();
653 else if (!ret || err_msg) {
654 /* We have to get I/O multiplexing started so that we can
655 * get the error back to the client. This means getting
656 * the protocol setup finished first in later versions. */
657 setup_protocol(f_out, f_in);
659 /* Since we failed in our option parsing, we may not
660 * have finished parsing that the client sent us a
661 * --files-from option, so look for it manually.
662 * Without this, the socket would be in the wrong
663 * state for the upcoming error message. */
666 for (i = 0; i < argc; i++) {
667 if (strncmp(argv[i], "--files-from", 12) == 0) {
674 write_byte(f_out, 0);
676 io_start_multiplex_out();
679 if (!ret || err_msg) {
681 rprintf(FERROR, err_msg);
685 exit_cleanup(RERR_UNSUPPORTED);
688 if (lp_timeout(i) && lp_timeout(i) > io_timeout)
689 set_io_timeout(lp_timeout(i));
691 /* If we have some incoming/outgoing chmod changes, append them to
692 * any user-specified changes (making our changes have priority).
693 * We also get a pointer to just our changes so that a receiver
694 * process can use them separately if --perms wasn't specified. */
696 p = lp_outgoing_chmod(i);
698 p = lp_incoming_chmod(i);
699 if (*p && !(daemon_chmod_modes = parse_chmod(p, &chmod_modes))) {
700 rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n",
701 am_sender ? "outgo" : "incom", p);
704 start_server(f_in, f_out, argc, argv);
709 /* send a list of available modules to the client. Don't list those
710 with "list = False". */
711 static void send_listing(int fd)
713 int n = lp_numservices();
716 for (i = 0; i < n; i++) {
718 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
721 if (protocol_version >= 25)
722 io_printf(fd,"@RSYNCD: EXIT\n");
725 /* this is called when a connection is established to a client
726 and we want to start talking. The setup of the system is done from
728 int start_daemon(int f_in, int f_out)
731 char *motd, *addr, *host;
734 io_set_sock_fds(f_in, f_out);
736 /* We must load the config file before calling any function that
737 * might cause log-file output to occur. This ensures that the
738 * "log file" param gets honored for the 2 non-forked use-cases
739 * (when rsync is run by init and run by a remote shell). */
740 if (!lp_load(config_file, 0))
741 exit_cleanup(RERR_SYNTAX);
743 addr = client_addr(f_in);
744 host = client_name(f_in);
745 rprintf(FLOG, "connect from %s (%s)\n", host, addr);
748 set_socket_options(f_in, "SO_KEEPALIVE");
750 set_socket_options(f_in, sockopts);
752 set_socket_options(f_in, lp_socket_options());
753 set_nonblocking(f_in);
756 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
758 motd = lp_motd_file();
760 FILE *f = fopen(motd,"r");
761 while (f && !feof(f)) {
762 int len = fread(line, 1, sizeof line - 1, f);
765 io_printf(f_out, "%s", line);
770 io_printf(f_out, "\n");
773 if (!read_line(f_in, line, sizeof line - 1))
776 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
777 io_printf(f_out, "@ERROR: protocol startup error\n");
780 if (protocol_version > remote_protocol)
781 protocol_version = remote_protocol;
784 if (!read_line(f_in, line, sizeof line - 1))
787 if (!*line || strcmp(line, "#list") == 0) {
788 rprintf(FLOG, "module-list request from %s (%s)\n",
795 /* it's some sort of command that I don't understand */
796 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
800 if ((i = lp_number(line)) < 0) {
801 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
803 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
807 #ifdef HAVE_SIGACTION
808 sigact.sa_flags = SA_NOCLDSTOP;
810 SIGACTION(SIGCHLD, remember_children);
812 return rsync_module(f_in, f_out, i, addr, host);
815 int daemon_main(void)
819 if (is_a_socket(STDIN_FILENO)) {
822 /* we are running via inetd - close off stdout and
823 * stderr so that library functions (and getopt) don't
824 * try to use them. Redirect them to /dev/null */
825 for (i = 1; i < 3; i++) {
827 open("/dev/null", O_RDWR);
830 return start_daemon(STDIN_FILENO, STDIN_FILENO);
836 if (!lp_load(config_file, 1))
837 exit_cleanup(RERR_SYNTAX);
839 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
840 rsync_port = RSYNC_PORT;
841 if (bind_address == NULL && *lp_bind_address())
842 bind_address = lp_bind_address();
846 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
847 RSYNC_VERSION, rsync_port);
848 /* TODO: If listening on a particular address, then show that
849 * address too. In fact, why not just do inet_ntop on the
850 * local address??? */
852 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
855 pid_t pid = getpid();
856 cleanup_set_pid(pid);
857 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
858 0666 & ~orig_umask)) == -1) {
860 rsyserr(FLOG, errno, "failed to create pid file %s",
862 exit_cleanup(RERR_FILEIO);
864 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
865 write(fd, pidbuf, strlen(pidbuf));
869 start_accept_loop(rsync_port, start_daemon);