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 kludge_around_eof;
39 extern int daemon_over_rsh;
41 extern int sanitize_paths;
42 extern int filesfrom_fd;
43 extern int remote_protocol;
44 extern int protocol_version;
45 extern int io_timeout;
46 extern int select_timeout;
47 extern int orig_umask;
49 extern int default_af_hint;
50 extern char *bind_address;
51 extern struct exclude_list_struct server_exclude_list;
52 extern char *config_file;
53 extern char *files_from;
57 /* Length of lp_path() string when in daemon mode & not chrooted, else 0. */
58 unsigned int module_dirlen = 0;
61 * Run a client connected to an rsyncd. The alternative to this
62 * function for remote-shell connections is do_cmd().
64 * After negotiating which module to use and reading the server's
65 * motd, this hands over to client_run(). Telling the server the
66 * module will cause it to chroot/setuid/etc.
68 * Instead of doing a transfer, the client may at this stage instead
69 * get a listing of remote modules and exit.
71 * @return -1 for error in startup, or the result of client_run().
72 * Either way, it eventually gets passed to exit_cleanup().
74 int start_socket_client(char *host, char *path, int argc, char *argv[])
77 char *p, *user = NULL;
79 /* This is redundant with code in start_inband_exchange(), but this
80 * short-circuits a problem in the client before we open a socket,
81 * and the extra check won't hurt. */
84 "ERROR: The remote path must start with a module name not a /\n");
88 if ((p = strchr(host, '@')) != NULL) {
95 rsync_port = RSYNC_PORT;
97 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
100 exit_cleanup(RERR_SOCKETIO);
102 ret = start_inband_exchange(user, path, fd, fd, argc);
104 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
107 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
111 char *sargs[MAX_ARGS];
113 char line[MAXPATHLEN];
116 if (argc == 0 && !am_sender)
121 "ERROR: The remote path must start with a module name\n");
126 user = getenv("USER");
128 user = getenv("LOGNAME");
130 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
132 if (!read_line(f_in, line, sizeof line - 1)) {
133 rprintf(FERROR, "rsync: did not see server greeting\n");
137 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
138 /* note that read_line strips of \n or \r */
139 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
143 if (protocol_version > remote_protocol)
144 protocol_version = remote_protocol;
146 if (list_only && protocol_version >= 29)
149 /* set daemon_over_rsh to false since we need to build the
150 * true set of args passed through the rsh/ssh connection;
151 * this is a no-op for direct-socket-connection mode */
153 server_options(sargs, &sargc);
155 sargs[sargc++] = ".";
158 sargs[sargc++] = path;
163 print_child_argv(sargs);
165 p = strchr(path,'/');
167 io_printf(f_out, "%s\n", path);
170 /* Old servers may just drop the connection here,
171 rather than sending a proper EXIT command. Yuck. */
172 kludge_around_eof = list_only && (protocol_version < 25);
175 if (!read_line(f_in, line, sizeof line - 1)) {
176 rprintf(FERROR, "rsync: didn't get server startup line\n");
180 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
181 auth_client(f_out, user, line+18);
185 if (strcmp(line,"@RSYNCD: OK") == 0)
188 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
189 /* This is sent by recent versions of the
190 * server to terminate the listing of modules.
191 * We don't want to go on and transfer
192 * anything; just exit. */
196 if (strncmp(line, "@ERROR", 6) == 0) {
197 rprintf(FERROR, "%s\n", line);
198 /* This is always fatal; the server will now
199 * close the socket. */
200 return RERR_STARTCLIENT;
202 rprintf(FINFO,"%s\n", line);
205 kludge_around_eof = False;
207 for (i = 0; i < sargc; i++) {
208 io_printf(f_out, "%s\n", sargs[i]);
210 io_printf(f_out, "\n");
212 if (protocol_version < 23) {
213 if (protocol_version == 22 || !am_sender)
214 io_start_multiplex_in();
222 static int rsync_module(int f_in, int f_out, int i)
228 char line[MAXPATHLEN];
229 uid_t uid = (uid_t)-2; /* canonically "nobody" */
230 gid_t gid = (gid_t)-2;
232 char *addr = client_addr(f_in);
233 char *host = client_name(f_in);
234 char *name = lp_name(i);
235 int use_chroot = lp_use_chroot(i);
238 char *request = NULL;
240 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
241 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
244 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
247 "@ERROR: access denied to %s from %s (%s)\n",
253 if (am_daemon && am_server) {
254 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
258 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
260 rsyserr(FLOG, errno, "failed to open lock file %s",
262 io_printf(f_out, "@ERROR: failed to open lock file %s\n",
265 rprintf(FLOG, "max connections (%d) reached\n",
266 lp_max_connections(i));
267 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n",
268 lp_max_connections(i));
273 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
276 rprintf(FLOG, "auth failed on module %s from %s (%s)\n",
278 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
284 am_root = (MY_UID() == 0);
288 if (!name_to_uid(p, &uid)) {
289 if (!isdigit(*(unsigned char *)p)) {
290 rprintf(FLOG, "Invalid uid %s\n", p);
291 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
298 if (!name_to_gid(p, &gid)) {
299 if (!isdigit(*(unsigned char *)p)) {
300 rprintf(FLOG, "Invalid gid %s\n", p);
301 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
308 /* TODO: If we're not root, but the configuration requests
309 * that we change to some uid other than the current one, then
312 /* TODO: Perhaps take a list of gids, and make them into the
313 * supplementary groups. */
317 set_excludes_dir("/", 1);
319 module_dirlen = strlen(lp_path(i));
320 set_excludes_dir(lp_path(i), module_dirlen);
324 add_exclude(&server_exclude_list, p,
325 XFLG_WORD_SPLIT | XFLG_ABS_PATH);
327 p = lp_include_from(i);
328 add_exclude_file(&server_exclude_list, p,
329 XFLG_FATAL_ERRORS | XFLG_ABS_PATH | XFLG_DEF_INCLUDE);
332 add_exclude(&server_exclude_list, p,
333 XFLG_WORD_SPLIT | XFLG_ABS_PATH | XFLG_DEF_INCLUDE);
335 p = lp_exclude_from(i);
336 add_exclude_file(&server_exclude_list, p,
337 XFLG_FATAL_ERRORS | XFLG_ABS_PATH | XFLG_DEF_EXCLUDE);
340 add_exclude(&server_exclude_list, p,
341 XFLG_WORD_SPLIT | XFLG_ABS_PATH | XFLG_DEF_EXCLUDE);
347 * XXX: The 'use chroot' flag is a fairly reliable
348 * source of confusion, because it fails under two
349 * important circumstances: running as non-root,
350 * running on Win32 (or possibly others). On the
351 * other hand, if you are running as root, then it
352 * might be better to always use chroot.
354 * So, perhaps if we can't chroot we should just issue
355 * a warning, unless a "require chroot" flag is set,
356 * in which case we fail.
358 if (chroot(lp_path(i))) {
359 rsyserr(FLOG, errno, "chroot %s failed", lp_path(i));
360 io_printf(f_out, "@ERROR: chroot failed\n");
364 if (!push_dir("/")) {
365 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
366 io_printf(f_out, "@ERROR: chdir failed\n");
371 if (!push_dir(lp_path(i))) {
372 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
373 io_printf(f_out, "@ERROR: chdir failed\n");
380 /* XXXX: You could argue that if the daemon is started
381 * by a non-root user and they explicitly specify a
382 * gid, then we should try to change to that gid --
383 * this could be possible if it's already in their
384 * supplementary groups. */
386 /* TODO: Perhaps we need to document that if rsyncd is
387 * started by somebody other than root it will inherit
388 * all their supplementary groups. */
391 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
392 io_printf(f_out, "@ERROR: setgid failed\n");
395 #ifdef HAVE_SETGROUPS
396 /* Get rid of any supplementary groups this process
397 * might have inheristed. */
398 if (setgroups(1, &gid)) {
399 rsyserr(FLOG, errno, "setgroups failed");
400 io_printf(f_out, "@ERROR: setgroups failed\n");
406 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
407 io_printf(f_out, "@ERROR: setuid failed\n");
411 am_root = (MY_UID() == 0);
414 io_printf(f_out, "@RSYNCD: OK\n");
417 if (!(argv = new_array(char *, maxargs)))
418 out_of_memory("rsync_module");
419 argv[argc++] = "rsyncd";
422 if (!read_line(f_in, line, sizeof line - 1))
430 if (argc == maxargs) {
432 if (!(argv = realloc_array(argv, char *, maxargs)))
433 out_of_memory("rsync_module");
435 if (!(argv[argc] = strdup(p)))
436 out_of_memory("rsync_module");
439 if (start_glob == 1) {
443 glob_expand(name, &argv, &argc, &maxargs);
447 if (strcmp(line, ".") == 0)
452 ret = parse_arguments(&argc, (const char ***) &argp, 0);
454 if (filesfrom_fd == 0)
459 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
460 am_sender ? "on" : "to",
461 request, auth_user, host, addr);
463 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
464 am_sender ? "on" : "to",
465 request, host, addr);
471 /* don't allow the logs to be flooded too fast */
472 if (verbose > lp_max_verbosity())
473 verbose = lp_max_verbosity();
476 if (protocol_version < 23
477 && (protocol_version == 22 || am_sender))
478 io_start_multiplex_out();
480 /* We have to get I/O multiplexing started so that we can
481 * get the error back to the client. This means getting
482 * the protocol setup finished first in later versions. */
483 setup_protocol(f_out, f_in);
484 if (files_from && !am_sender && strcmp(files_from, "-") != 0)
485 write_byte(f_out, 0);
486 io_start_multiplex_out();
492 exit_cleanup(RERR_UNSUPPORTED);
496 io_timeout = lp_timeout(i);
497 if (io_timeout < select_timeout)
498 select_timeout = io_timeout;
501 start_server(f_in, f_out, argc, argp);
506 /* send a list of available modules to the client. Don't list those
507 with "list = False". */
508 static void send_listing(int fd)
510 int n = lp_numservices();
513 for (i = 0; i < n; i++) {
515 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
518 if (protocol_version >= 25)
519 io_printf(fd,"@RSYNCD: EXIT\n");
522 /* this is called when a connection is established to a client
523 and we want to start talking. The setup of the system is done from
525 int start_daemon(int f_in, int f_out)
531 io_set_sock_fds(f_in, f_out);
533 if (!lp_load(config_file, 0))
534 exit_cleanup(RERR_SYNTAX);
539 set_socket_options(f_in, "SO_KEEPALIVE");
540 set_socket_options(f_in, lp_socket_options());
541 set_nonblocking(f_in);
544 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
546 motd = lp_motd_file();
548 FILE *f = fopen(motd,"r");
549 while (f && !feof(f)) {
550 int len = fread(line, 1, sizeof line - 1, f);
553 io_printf(f_out, "%s", line);
558 io_printf(f_out, "\n");
561 if (!read_line(f_in, line, sizeof line - 1))
564 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
565 io_printf(f_out, "@ERROR: protocol startup error\n");
568 if (protocol_version > remote_protocol)
569 protocol_version = remote_protocol;
572 if (!read_line(f_in, line, sizeof line - 1))
575 if (!*line || strcmp(line, "#list") == 0) {
581 /* it's some sort of command that I don't understand */
582 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
586 if ((i = lp_number(line)) < 0) {
587 char *addr = client_addr(f_in);
588 char *host = client_name(f_in);
589 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
591 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
595 return rsync_module(f_in, f_out, i);
599 int daemon_main(void)
603 if (is_a_socket(STDIN_FILENO)) {
606 /* we are running via inetd - close off stdout and
607 * stderr so that library functions (and getopt) don't
608 * try to use them. Redirect them to /dev/null */
609 for (i = 1; i < 3; i++) {
611 open("/dev/null", O_RDWR);
614 return start_daemon(STDIN_FILENO, STDIN_FILENO);
620 if (!lp_load(config_file, 1))
621 exit_cleanup(RERR_SYNTAX);
623 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
624 rsync_port = RSYNC_PORT;
625 if (bind_address == NULL && *lp_bind_address())
626 bind_address = lp_bind_address();
630 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
631 RSYNC_VERSION, rsync_port);
632 /* TODO: If listening on a particular address, then show that
633 * address too. In fact, why not just do inet_ntop on the
634 * local address??? */
636 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
639 pid_t pid = getpid();
640 cleanup_set_pid(pid);
641 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
642 0666 & ~orig_umask)) == -1) {
644 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
645 exit_cleanup(RERR_FILEIO);
647 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
648 write(fd, pidbuf, strlen(pidbuf));
652 start_accept_loop(rsync_port, start_daemon);