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;
45 extern int orig_umask;
47 extern int default_af_hint;
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;
62 /* Length of lp_path() string when in daemon mode & not chrooted, else 0. */
63 unsigned int module_dirlen = 0;
66 * Run a client connected to an rsyncd. The alternative to this
67 * function for remote-shell connections is do_cmd().
69 * After negotiating which module to use and reading the server's
70 * motd, this hands over to client_run(). Telling the server the
71 * module will cause it to chroot/setuid/etc.
73 * Instead of doing a transfer, the client may at this stage instead
74 * get a listing of remote modules and exit.
76 * @return -1 for error in startup, or the result of client_run().
77 * Either way, it eventually gets passed to exit_cleanup().
79 int start_socket_client(char *host, char *path, int argc, char *argv[])
82 char *p, *user = NULL;
84 /* This is redundant with code in start_inband_exchange(), but this
85 * short-circuits a problem in the client before we open a socket,
86 * and the extra check won't hurt. */
89 "ERROR: The remote path must start with a module name not a /\n");
93 if ((p = strrchr(host, '@')) != NULL) {
99 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
102 exit_cleanup(RERR_SOCKETIO);
104 set_socket_options(fd, sockopts);
106 ret = start_inband_exchange(user, path, fd, fd, argc);
108 return ret ? ret : client_run(fd, fd, -1, argc, argv);
111 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
115 char *sargs[MAX_ARGS];
117 char line[BIGPATHBUFLEN];
120 if (argc == 0 && !am_sender)
125 "ERROR: The remote path must start with a module name\n");
130 user = getenv("USER");
132 user = getenv("LOGNAME");
134 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
136 if (!read_line(f_in, line, sizeof line - 1)) {
137 rprintf(FERROR, "rsync: did not see server greeting\n");
141 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
142 /* note that read_line strips of \n or \r */
143 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
147 if (protocol_version > remote_protocol)
148 protocol_version = remote_protocol;
150 if (list_only && protocol_version >= 29)
153 /* set daemon_over_rsh to false since we need to build the
154 * true set of args passed through the rsh/ssh connection;
155 * this is a no-op for direct-socket-connection mode */
157 server_options(sargs, &sargc);
159 sargs[sargc++] = ".";
162 sargs[sargc++] = path;
167 print_child_argv(sargs);
169 p = strchr(path,'/');
171 io_printf(f_out, "%s\n", path);
174 /* Old servers may just drop the connection here,
175 rather than sending a proper EXIT command. Yuck. */
176 kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
179 if (!read_line(f_in, line, sizeof line - 1)) {
180 rprintf(FERROR, "rsync: didn't get server startup line\n");
184 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
185 auth_client(f_out, user, line+18);
189 if (strcmp(line,"@RSYNCD: OK") == 0)
192 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
193 /* This is sent by recent versions of the
194 * server to terminate the listing of modules.
195 * We don't want to go on and transfer
196 * anything; just exit. */
200 if (strncmp(line, "@ERROR", 6) == 0) {
201 rprintf(FERROR, "%s\n", line);
202 /* This is always fatal; the server will now
203 * close the socket. */
207 rprintf(FINFO, "%s\n", line);
209 kluge_around_eof = 0;
211 for (i = 0; i < sargc; i++) {
212 io_printf(f_out, "%s\n", sargs[i]);
214 io_printf(f_out, "\n");
216 if (protocol_version < 23) {
217 if (protocol_version == 22 || !am_sender)
218 io_start_multiplex_in();
224 static char *finish_pre_exec(pid_t pid, int fd, char *request,
225 int argc, char *argv[])
230 write_buf(fd, request, strlen(request)+1);
231 for (j = 0; j < argc; j++)
232 write_buf(fd, argv[j], strlen(argv[j])+1);
239 if (wait_process(pid, &status, 0) < 0
240 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
242 if (asprintf(&e, "pre-xfer exec returned failure (%d)\n", status) < 0)
243 out_of_memory("finish_pre_exec");
249 static int read_arg_from_pipe(int fd, char *buf, int limit)
251 char *bp = buf, *eob = buf + limit - 1;
254 if (read(fd, bp, 1) != 1)
266 static int rsync_module(int f_in, int f_out, int i)
271 char line[BIGPATHBUFLEN];
272 uid_t uid = (uid_t)-2; /* canonically "nobody" */
273 gid_t gid = (gid_t)-2;
274 char *p, *err_msg = NULL;
275 char *addr = client_addr(f_in);
276 char *host = client_name(f_in);
277 char *name = lp_name(i);
278 int use_chroot = lp_use_chroot(i);
280 int ret, pre_exec_fd = -1;
281 pid_t pre_exec_pid = 0;
282 char *request = NULL;
284 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
285 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
288 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
291 "@ERROR: access denied to %s from %s (%s)\n",
297 if (am_daemon && am_server) {
298 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
302 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
304 rsyserr(FLOG, errno, "failed to open lock file %s",
306 io_printf(f_out, "@ERROR: failed to open lock file\n");
308 rprintf(FLOG, "max connections (%d) reached\n",
309 lp_max_connections(i));
310 io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
311 lp_max_connections(i));
316 auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
319 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
328 if (lp_transfer_logging(i)) {
329 if (log_format_has(lp_log_format(i), 'i'))
330 daemon_log_format_has_i = 1;
331 if (daemon_log_format_has_i
332 || log_format_has(lp_log_format(i), 'o'))
333 daemon_log_format_has_o_or_i = 1;
336 am_root = (MY_UID() == 0);
340 if (!name_to_uid(p, &uid)) {
341 if (!isdigit(*(unsigned char *)p)) {
342 rprintf(FLOG, "Invalid uid %s\n", p);
343 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
350 if (!name_to_gid(p, &gid)) {
351 if (!isdigit(*(unsigned char *)p)) {
352 rprintf(FLOG, "Invalid gid %s\n", p);
353 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
360 /* TODO: If we're not root, but the configuration requests
361 * that we change to some uid other than the current one, then
364 /* TODO: Perhaps take a list of gids, and make them into the
365 * supplementary groups. */
367 if (use_chroot || (module_dirlen = strlen(lp_path(i))) == 1) {
369 set_filter_dir("/", 1);
371 set_filter_dir(lp_path(i), module_dirlen);
374 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
377 p = lp_include_from(i);
378 parse_filter_file(&server_filter_list, p, MATCHFLG_INCLUDE,
379 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
382 parse_rule(&server_filter_list, p,
383 MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT,
384 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES);
386 p = lp_exclude_from(i);
387 parse_filter_file(&server_filter_list, p, 0,
388 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
391 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
392 XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES);
397 if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) {
398 char *modname, *modpath, *hostaddr, *hostname, *username;
400 if (asprintf(&modname, "RSYNC_MODULE_NAME=%s", name) < 0
401 || asprintf(&modpath, "RSYNC_MODULE_PATH=%s", lp_path(i)) < 0
402 || asprintf(&hostaddr, "RSYNC_HOST_ADDR=%s", addr) < 0
403 || asprintf(&hostname, "RSYNC_HOST_NAME=%s", host) < 0
404 || asprintf(&username, "RSYNC_USER_NAME=%s", auth_user) < 0)
405 out_of_memory("rsync_module");
412 /* For post-xfer exec, fork a new process to run the rsync
413 * daemon while this process waits for the exit status and
414 * runs the indicated command at that point. */
415 if (*lp_postxfer_exec(i)) {
418 rsyserr(FLOG, errno, "fork failed");
419 io_printf(f_out, "@ERROR: fork failed\n");
424 if (wait_process(pid, &status, 0) < 0)
426 if (asprintf(&ret1, "RSYNC_RAW_STATUS=%d", status) > 0)
428 if (WIFEXITED(status))
429 status = WEXITSTATUS(status);
432 if (asprintf(&ret2, "RSYNC_EXIT_STATUS=%d", status) > 0)
434 system(lp_postxfer_exec(i));
438 /* For pre-xfer exec, fork a child process to run the indicated
439 * command, though it first waits for the parent process to
440 * send us the user's request via a pipe. */
441 if (*lp_prexfer_exec(i)) {
443 if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) {
444 rsyserr(FLOG, errno, "pre-xfer exec preparation failed");
445 io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n");
448 if (pre_exec_pid == 0) {
449 char buf[BIGPATHBUFLEN];
452 set_blocking(fds[0]);
453 len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN);
456 if (asprintf(&p, "RSYNC_REQUEST=%s", buf) < 0)
457 out_of_memory("rsync_module");
460 len = read_arg_from_pipe(fds[0], buf,
467 if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) < 0)
468 out_of_memory("rsync_module");
473 close(STDOUT_FILENO);
474 status = system(lp_prexfer_exec(i));
475 if (!WIFEXITED(status))
477 _exit(WEXITSTATUS(status));
480 set_blocking(fds[1]);
481 pre_exec_fd = fds[1];
489 * XXX: The 'use chroot' flag is a fairly reliable
490 * source of confusion, because it fails under two
491 * important circumstances: running as non-root,
492 * running on Win32 (or possibly others). On the
493 * other hand, if you are running as root, then it
494 * might be better to always use chroot.
496 * So, perhaps if we can't chroot we should just issue
497 * a warning, unless a "require chroot" flag is set,
498 * in which case we fail.
500 if (chroot(lp_path(i))) {
501 rsyserr(FLOG, errno, "chroot %s failed",
503 io_printf(f_out, "@ERROR: chroot failed\n");
507 if (!push_dir("/")) {
508 rsyserr(FLOG, errno, "chdir %s failed\n",
510 io_printf(f_out, "@ERROR: chdir failed\n");
515 if (!push_dir(lp_path(i))) {
516 rsyserr(FLOG, errno, "chdir %s failed\n",
518 io_printf(f_out, "@ERROR: chdir failed\n");
525 /* XXXX: You could argue that if the daemon is started
526 * by a non-root user and they explicitly specify a
527 * gid, then we should try to change to that gid --
528 * this could be possible if it's already in their
529 * supplementary groups. */
531 /* TODO: Perhaps we need to document that if rsyncd is
532 * started by somebody other than root it will inherit
533 * all their supplementary groups. */
536 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
537 io_printf(f_out, "@ERROR: setgid failed\n");
540 #ifdef HAVE_SETGROUPS
541 /* Get rid of any supplementary groups this process
542 * might have inheristed. */
543 if (setgroups(1, &gid)) {
544 rsyserr(FLOG, errno, "setgroups failed");
545 io_printf(f_out, "@ERROR: setgroups failed\n");
551 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
552 io_printf(f_out, "@ERROR: setuid failed\n");
556 am_root = (MY_UID() == 0);
559 if (lp_temp_dir(i) && *lp_temp_dir(i)) {
560 tmpdir = lp_temp_dir(i);
561 if (strlen(tmpdir) >= MAXPATHLEN - 10) {
563 "the 'temp dir' value for %s is WAY too long -- ignoring.\n",
569 io_printf(f_out, "@RSYNCD: OK\n");
572 if (!(argv = new_array(char *, maxargs)))
573 out_of_memory("rsync_module");
574 argv[argc++] = "rsyncd";
577 if (!read_line(f_in, line, sizeof line - 1))
585 if (argc == maxargs) {
587 if (!(argv = realloc_array(argv, char *, maxargs)))
588 out_of_memory("rsync_module");
590 if (!(argv[argc] = strdup(p)))
591 out_of_memory("rsync_module");
593 switch (start_glob) {
596 if (strcmp(line, ".") == 0)
601 err_msg = finish_pre_exec(pre_exec_pid,
611 glob_expand(name, &argv, &argc, &maxargs);
617 err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request,
621 verbose = 0; /* future verbosity is controlled by client options */
622 ret = parse_arguments(&argc, (const char ***) &argv, 0);
623 quiet = 0; /* Don't let someone try to be tricky. */
625 if (filesfrom_fd == 0)
630 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
631 am_sender ? "on" : "to",
632 request, auth_user, host, addr);
634 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
635 am_sender ? "on" : "to",
636 request, host, addr);
642 /* don't allow the logs to be flooded too fast */
643 if (verbose > lp_max_verbosity(i))
644 verbose = lp_max_verbosity(i);
647 if (protocol_version < 23
648 && (protocol_version == 22 || am_sender))
649 io_start_multiplex_out();
650 else if (!ret || err_msg) {
651 /* We have to get I/O multiplexing started so that we can
652 * get the error back to the client. This means getting
653 * the protocol setup finished first in later versions. */
654 setup_protocol(f_out, f_in);
656 /* Since we failed in our option parsing, we may not
657 * have finished parsing that the client sent us a
658 * --files-from option, so look for it manually.
659 * Without this, the socket would be in the wrong
660 * state for the upcoming error message. */
663 for (i = 0; i < argc; i++) {
664 if (strncmp(argv[i], "--files-from", 12) == 0) {
671 write_byte(f_out, 0);
673 io_start_multiplex_out();
676 if (!ret || err_msg) {
678 rprintf(FERROR, err_msg);
682 exit_cleanup(RERR_UNSUPPORTED);
685 if (lp_timeout(i) && lp_timeout(i) > io_timeout)
686 set_io_timeout(lp_timeout(i));
690 p = lp_outgoing_chmod(i);
692 p = lp_incoming_chmod(i);
693 if (*p && !parse_chmod(p, &chmod_modes)) {
694 rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n",
695 am_sender ? "outgo" : "incom", p);
698 start_server(f_in, f_out, argc, argv);
703 /* send a list of available modules to the client. Don't list those
704 with "list = False". */
705 static void send_listing(int fd)
707 int n = lp_numservices();
710 for (i = 0; i < n; i++) {
712 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
715 if (protocol_version >= 25)
716 io_printf(fd,"@RSYNCD: EXIT\n");
719 /* this is called when a connection is established to a client
720 and we want to start talking. The setup of the system is done from
722 int start_daemon(int f_in, int f_out)
728 io_set_sock_fds(f_in, f_out);
730 if (!lp_load(config_file, 0))
731 exit_cleanup(RERR_SYNTAX);
736 set_socket_options(f_in, "SO_KEEPALIVE");
738 set_socket_options(f_in, sockopts);
740 set_socket_options(f_in, lp_socket_options());
741 set_nonblocking(f_in);
744 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
746 motd = lp_motd_file();
748 FILE *f = fopen(motd,"r");
749 while (f && !feof(f)) {
750 int len = fread(line, 1, sizeof line - 1, f);
753 io_printf(f_out, "%s", line);
758 io_printf(f_out, "\n");
761 if (!read_line(f_in, line, sizeof line - 1))
764 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
765 io_printf(f_out, "@ERROR: protocol startup error\n");
768 if (protocol_version > remote_protocol)
769 protocol_version = remote_protocol;
772 if (!read_line(f_in, line, sizeof line - 1))
775 if (!*line || strcmp(line, "#list") == 0) {
781 /* it's some sort of command that I don't understand */
782 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
786 if ((i = lp_number(line)) < 0) {
787 char *addr = client_addr(f_in);
788 char *host = client_name(f_in);
789 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
791 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
795 return rsync_module(f_in, f_out, i);
798 int daemon_main(void)
802 if (is_a_socket(STDIN_FILENO)) {
805 /* we are running via inetd - close off stdout and
806 * stderr so that library functions (and getopt) don't
807 * try to use them. Redirect them to /dev/null */
808 for (i = 1; i < 3; i++) {
810 open("/dev/null", O_RDWR);
813 return start_daemon(STDIN_FILENO, STDIN_FILENO);
819 if (!lp_load(config_file, 1))
820 exit_cleanup(RERR_SYNTAX);
822 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
823 rsync_port = RSYNC_PORT;
824 if (bind_address == NULL && *lp_bind_address())
825 bind_address = lp_bind_address();
829 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
830 RSYNC_VERSION, rsync_port);
831 /* TODO: If listening on a particular address, then show that
832 * address too. In fact, why not just do inet_ntop on the
833 * local address??? */
835 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
838 pid_t pid = getpid();
839 cleanup_set_pid(pid);
840 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
841 0666 & ~orig_umask)) == -1) {
843 rsyserr(FLOG, errno, "failed to create pid file %s",
845 exit_cleanup(RERR_FILEIO);
847 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
848 write(fd, pidbuf, strlen(pidbuf));
852 start_accept_loop(rsync_port, start_daemon);