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
36 extern int rsync_port;
37 extern int kluge_around_eof;
38 extern int daemon_over_rsh;
39 extern int sanitize_paths;
40 extern int filesfrom_fd;
41 extern int remote_protocol;
42 extern int protocol_version;
43 extern int io_timeout;
44 extern int orig_umask;
46 extern int default_af_hint;
47 extern char *bind_address;
48 extern char *sockopts;
49 extern char *config_file;
50 extern char *files_from;
52 extern struct chmod_mode_struct *chmod_modes;
53 extern struct filter_list_struct server_filter_list;
57 int daemon_log_format_has_i = 0;
58 int daemon_log_format_has_o_or_i = 0;
61 /* Length of lp_path() string when in daemon mode & not chrooted, else 0. */
62 unsigned int module_dirlen = 0;
65 * Run a client connected to an rsyncd. The alternative to this
66 * function for remote-shell connections is do_cmd().
68 * After negotiating which module to use and reading the server's
69 * motd, this hands over to client_run(). Telling the server the
70 * module will cause it to chroot/setuid/etc.
72 * Instead of doing a transfer, the client may at this stage instead
73 * get a listing of remote modules and exit.
75 * @return -1 for error in startup, or the result of client_run().
76 * Either way, it eventually gets passed to exit_cleanup().
78 int start_socket_client(char *host, char *path, int argc, char *argv[])
81 char *p, *user = NULL;
83 /* This is redundant with code in start_inband_exchange(), but this
84 * short-circuits a problem in the client before we open a socket,
85 * and the extra check won't hurt. */
88 "ERROR: The remote path must start with a module name not a /\n");
92 if ((p = strrchr(host, '@')) != NULL) {
98 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
101 exit_cleanup(RERR_SOCKETIO);
103 set_socket_options(fd, sockopts);
105 ret = start_inband_exchange(user, path, fd, fd, argc);
107 return ret ? ret : client_run(fd, fd, -1, argc, argv);
110 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
114 char *sargs[MAX_ARGS];
116 char line[BIGPATHBUFLEN];
119 if (argc == 0 && !am_sender)
124 "ERROR: The remote path must start with a module name\n");
129 user = getenv("USER");
131 user = getenv("LOGNAME");
133 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
135 if (!read_line(f_in, line, sizeof line - 1)) {
136 rprintf(FERROR, "rsync: did not see server greeting\n");
140 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
141 /* note that read_line strips of \n or \r */
142 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
146 if (protocol_version > remote_protocol)
147 protocol_version = remote_protocol;
149 if (list_only && protocol_version >= 29)
152 /* set daemon_over_rsh to false since we need to build the
153 * true set of args passed through the rsh/ssh connection;
154 * this is a no-op for direct-socket-connection mode */
156 server_options(sargs, &sargc);
158 sargs[sargc++] = ".";
161 sargs[sargc++] = path;
166 print_child_argv(sargs);
168 p = strchr(path,'/');
170 io_printf(f_out, "%s\n", path);
173 /* Old servers may just drop the connection here,
174 rather than sending a proper EXIT command. Yuck. */
175 kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
178 if (!read_line(f_in, line, sizeof line - 1)) {
179 rprintf(FERROR, "rsync: didn't get server startup line\n");
183 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
184 auth_client(f_out, user, line+18);
188 if (strcmp(line,"@RSYNCD: OK") == 0)
191 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
192 /* This is sent by recent versions of the
193 * server to terminate the listing of modules.
194 * We don't want to go on and transfer
195 * anything; just exit. */
199 if (strncmp(line, "@ERROR", 6) == 0) {
200 rprintf(FERROR, "%s\n", line);
201 /* This is always fatal; the server will now
202 * close the socket. */
206 rprintf(FINFO, "%s\n", line);
208 kluge_around_eof = 0;
210 for (i = 0; i < sargc; i++) {
211 io_printf(f_out, "%s\n", sargs[i]);
213 io_printf(f_out, "\n");
215 if (protocol_version < 23) {
216 if (protocol_version == 22 || !am_sender)
217 io_start_multiplex_in();
223 static char *finish_pre_exec(pid_t pid, int fd, char *request,
224 int argc, char *argv[])
229 write_buf(fd, request, strlen(request)+1);
230 for (j = 0; j < argc; j++)
231 write_buf(fd, argv[j], strlen(argv[j])+1);
238 if (wait_process(pid, &status, 0) < 0
239 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
241 if (asprintf(&e, "pre-xfer exec returned failure (%d)\n", status) < 0)
242 out_of_memory("finish_pre_exec");
248 static int read_arg_from_pipe(int fd, char *buf, int limit)
250 char *bp = buf, *eob = buf + limit - 1;
253 if (read(fd, bp, 1) != 1)
265 static int rsync_module(int f_in, int f_out, int i)
270 char line[BIGPATHBUFLEN];
271 uid_t uid = (uid_t)-2; /* canonically "nobody" */
272 gid_t gid = (gid_t)-2;
273 char *p, *err_msg = NULL;
274 char *addr = client_addr(f_in);
275 char *host = client_name(f_in);
276 char *name = lp_name(i);
277 int use_chroot = lp_use_chroot(i);
279 int ret, pre_exec_fd = -1;
280 pid_t pre_exec_pid = 0;
281 char *request = NULL;
283 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
284 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
287 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
290 "@ERROR: access denied to %s from %s (%s)\n",
296 if (am_daemon && am_server) {
297 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
301 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
303 rsyserr(FLOG, errno, "failed to open lock file %s",
305 io_printf(f_out, "@ERROR: failed to open lock file\n");
307 rprintf(FLOG, "max connections (%d) reached\n",
308 lp_max_connections(i));
309 io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
310 lp_max_connections(i));
315 auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
318 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
327 if (lp_transfer_logging(i)) {
328 if (log_format_has(lp_log_format(i), 'i'))
329 daemon_log_format_has_i = 1;
330 if (daemon_log_format_has_i
331 || log_format_has(lp_log_format(i), 'o'))
332 daemon_log_format_has_o_or_i = 1;
335 am_root = (MY_UID() == 0);
339 if (!name_to_uid(p, &uid)) {
340 if (!isdigit(*(unsigned char *)p)) {
341 rprintf(FLOG, "Invalid uid %s\n", p);
342 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
349 if (!name_to_gid(p, &gid)) {
350 if (!isdigit(*(unsigned char *)p)) {
351 rprintf(FLOG, "Invalid gid %s\n", p);
352 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
359 /* TODO: If we're not root, but the configuration requests
360 * that we change to some uid other than the current one, then
363 /* TODO: Perhaps take a list of gids, and make them into the
364 * supplementary groups. */
366 if (use_chroot || (module_dirlen = strlen(lp_path(i))) == 1) {
368 set_filter_dir("/", 1);
370 set_filter_dir(lp_path(i), module_dirlen);
373 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
376 p = lp_include_from(i);
377 parse_filter_file(&server_filter_list, p, MATCHFLG_INCLUDE,
378 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
381 parse_rule(&server_filter_list, p,
382 MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT,
383 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES);
385 p = lp_exclude_from(i);
386 parse_filter_file(&server_filter_list, p, 0,
387 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
390 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
391 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES);
396 if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) {
397 char *modname, *modpath, *hostaddr, *hostname, *username;
399 if (asprintf(&modname, "RSYNC_MODULE_NAME=%s", name) < 0
400 || asprintf(&modpath, "RSYNC_MODULE_PATH=%s", lp_path(i)) < 0
401 || asprintf(&hostaddr, "RSYNC_HOST_ADDR=%s", addr) < 0
402 || asprintf(&hostname, "RSYNC_HOST_NAME=%s", host) < 0
403 || asprintf(&username, "RSYNC_USER_NAME=%s", auth_user) < 0)
404 out_of_memory("rsync_module");
411 /* For post-xfer exec, fork a new process to run the rsync
412 * daemon while this process waits for the exit status and
413 * runs the indicated command at that point. */
414 if (*lp_postxfer_exec(i)) {
417 rsyserr(FLOG, errno, "fork failed");
418 io_printf(f_out, "@ERROR: fork failed\n");
423 if (wait_process(pid, &status, 0) < 0)
425 if (asprintf(&ret1, "RSYNC_RAW_STATUS=%d", status) > 0)
427 if (WIFEXITED(status))
428 status = WEXITSTATUS(status);
431 if (asprintf(&ret2, "RSYNC_EXIT_STATUS=%d", status) > 0)
433 system(lp_postxfer_exec(i));
437 /* For pre-xfer exec, fork a child process to run the indicated
438 * command, though it first waits for the parent process to
439 * send us the user's request via a pipe. */
440 if (*lp_prexfer_exec(i)) {
442 if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) {
443 rsyserr(FLOG, errno, "pre-xfer exec preparation failed");
444 io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n");
447 if (pre_exec_pid == 0) {
448 char buf[BIGPATHBUFLEN];
451 set_blocking(fds[0]);
452 len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN);
455 if (asprintf(&p, "RSYNC_REQUEST=%s", buf) < 0)
456 out_of_memory("rsync_module");
459 len = read_arg_from_pipe(fds[0], buf,
466 if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) < 0)
467 out_of_memory("rsync_module");
472 close(STDOUT_FILENO);
473 status = system(lp_prexfer_exec(i));
474 if (!WIFEXITED(status))
476 _exit(WEXITSTATUS(status));
479 set_blocking(fds[1]);
480 pre_exec_fd = fds[1];
488 * XXX: The 'use chroot' flag is a fairly reliable
489 * source of confusion, because it fails under two
490 * important circumstances: running as non-root,
491 * running on Win32 (or possibly others). On the
492 * other hand, if you are running as root, then it
493 * might be better to always use chroot.
495 * So, perhaps if we can't chroot we should just issue
496 * a warning, unless a "require chroot" flag is set,
497 * in which case we fail.
499 if (chroot(lp_path(i))) {
500 rsyserr(FLOG, errno, "chroot %s failed",
502 io_printf(f_out, "@ERROR: chroot failed\n");
506 if (!push_dir("/")) {
507 rsyserr(FLOG, errno, "chdir %s failed\n",
509 io_printf(f_out, "@ERROR: chdir failed\n");
514 if (!push_dir(lp_path(i))) {
515 rsyserr(FLOG, errno, "chdir %s failed\n",
517 io_printf(f_out, "@ERROR: chdir failed\n");
524 /* XXXX: You could argue that if the daemon is started
525 * by a non-root user and they explicitly specify a
526 * gid, then we should try to change to that gid --
527 * this could be possible if it's already in their
528 * supplementary groups. */
530 /* TODO: Perhaps we need to document that if rsyncd is
531 * started by somebody other than root it will inherit
532 * all their supplementary groups. */
535 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
536 io_printf(f_out, "@ERROR: setgid failed\n");
539 #ifdef HAVE_SETGROUPS
540 /* Get rid of any supplementary groups this process
541 * might have inheristed. */
542 if (setgroups(1, &gid)) {
543 rsyserr(FLOG, errno, "setgroups failed");
544 io_printf(f_out, "@ERROR: setgroups failed\n");
550 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
551 io_printf(f_out, "@ERROR: setuid failed\n");
555 am_root = (MY_UID() == 0);
558 if (lp_temp_dir(i) && *lp_temp_dir(i)) {
559 tmpdir = lp_temp_dir(i);
560 if (strlen(tmpdir) >= MAXPATHLEN - 10) {
562 "the 'temp dir' value for %s is WAY too long -- ignoring.\n",
568 io_printf(f_out, "@RSYNCD: OK\n");
571 if (!(argv = new_array(char *, maxargs)))
572 out_of_memory("rsync_module");
573 argv[argc++] = "rsyncd";
576 if (!read_line(f_in, line, sizeof line - 1))
584 if (argc == maxargs) {
586 if (!(argv = realloc_array(argv, char *, maxargs)))
587 out_of_memory("rsync_module");
589 if (!(argv[argc] = strdup(p)))
590 out_of_memory("rsync_module");
592 switch (start_glob) {
595 if (strcmp(line, ".") == 0)
600 err_msg = finish_pre_exec(pre_exec_pid,
610 glob_expand(name, &argv, &argc, &maxargs);
616 err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request,
620 verbose = 0; /* future verbosity is controlled by client options */
621 ret = parse_arguments(&argc, (const char ***) &argv, 0);
623 if (filesfrom_fd == 0)
628 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
629 am_sender ? "on" : "to",
630 request, auth_user, host, addr);
632 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
633 am_sender ? "on" : "to",
634 request, host, addr);
640 /* don't allow the logs to be flooded too fast */
641 if (verbose > lp_max_verbosity(i))
642 verbose = lp_max_verbosity(i);
645 if (protocol_version < 23
646 && (protocol_version == 22 || am_sender))
647 io_start_multiplex_out();
648 else if (!ret || err_msg) {
649 /* We have to get I/O multiplexing started so that we can
650 * get the error back to the client. This means getting
651 * the protocol setup finished first in later versions. */
652 setup_protocol(f_out, f_in);
654 /* Since we failed in our option parsing, we may not
655 * have finished parsing that the client sent us a
656 * --files-from option, so look for it manually.
657 * Without this, the socket would be in the wrong
658 * state for the upcoming error message. */
661 for (i = 0; i < argc; i++) {
662 if (strncmp(argv[i], "--files-from", 12) == 0) {
669 write_byte(f_out, 0);
671 io_start_multiplex_out();
674 if (!ret || err_msg) {
676 rprintf(FERROR, err_msg);
680 exit_cleanup(RERR_UNSUPPORTED);
683 if (lp_timeout(i) && lp_timeout(i) > io_timeout)
684 set_io_timeout(lp_timeout(i));
688 p = lp_outgoing_chmod(i);
690 p = lp_incoming_chmod(i);
691 if (*p && !parse_chmod(p, &chmod_modes)) {
692 rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n",
693 am_sender ? "outgo" : "incom", p);
696 start_server(f_in, f_out, argc, argv);
701 /* send a list of available modules to the client. Don't list those
702 with "list = False". */
703 static void send_listing(int fd)
705 int n = lp_numservices();
708 for (i = 0; i < n; i++) {
710 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
713 if (protocol_version >= 25)
714 io_printf(fd,"@RSYNCD: EXIT\n");
717 /* this is called when a connection is established to a client
718 and we want to start talking. The setup of the system is done from
720 int start_daemon(int f_in, int f_out)
726 io_set_sock_fds(f_in, f_out);
728 if (!lp_load(config_file, 0))
729 exit_cleanup(RERR_SYNTAX);
734 set_socket_options(f_in, "SO_KEEPALIVE");
736 set_socket_options(f_in, sockopts);
738 set_socket_options(f_in, lp_socket_options());
739 set_nonblocking(f_in);
742 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
744 motd = lp_motd_file();
746 FILE *f = fopen(motd,"r");
747 while (f && !feof(f)) {
748 int len = fread(line, 1, sizeof line - 1, f);
751 io_printf(f_out, "%s", line);
756 io_printf(f_out, "\n");
759 if (!read_line(f_in, line, sizeof line - 1))
762 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
763 io_printf(f_out, "@ERROR: protocol startup error\n");
766 if (protocol_version > remote_protocol)
767 protocol_version = remote_protocol;
770 if (!read_line(f_in, line, sizeof line - 1))
773 if (!*line || strcmp(line, "#list") == 0) {
779 /* it's some sort of command that I don't understand */
780 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
784 if ((i = lp_number(line)) < 0) {
785 char *addr = client_addr(f_in);
786 char *host = client_name(f_in);
787 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
789 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
793 return rsync_module(f_in, f_out, i);
796 int daemon_main(void)
800 if (is_a_socket(STDIN_FILENO)) {
803 /* we are running via inetd - close off stdout and
804 * stderr so that library functions (and getopt) don't
805 * try to use them. Redirect them to /dev/null */
806 for (i = 1; i < 3; i++) {
808 open("/dev/null", O_RDWR);
811 return start_daemon(STDIN_FILENO, STDIN_FILENO);
817 if (!lp_load(config_file, 1))
818 exit_cleanup(RERR_SYNTAX);
820 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
821 rsync_port = RSYNC_PORT;
822 if (bind_address == NULL && *lp_bind_address())
823 bind_address = lp_bind_address();
827 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
828 RSYNC_VERSION, rsync_port);
829 /* TODO: If listening on a particular address, then show that
830 * address too. In fact, why not just do inet_ntop on the
831 * local address??? */
833 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
836 pid_t pid = getpid();
837 cleanup_set_pid(pid);
838 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
839 0666 & ~orig_umask)) == -1) {
841 rsyserr(FLOG, errno, "failed to create pid file %s",
843 exit_cleanup(RERR_FILEIO);
845 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
846 write(fd, pidbuf, strlen(pidbuf));
850 start_accept_loop(rsync_port, start_daemon);