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 struct filter_list_struct server_filter_list;
49 extern char *config_file;
50 extern char *files_from;
54 int daemon_log_format_has_i = 0;
55 int daemon_log_format_has_o_or_i = 0;
58 /* Length of lp_path() string when in daemon mode & not chrooted, else 0. */
59 unsigned int module_dirlen = 0;
62 * Run a client connected to an rsyncd. The alternative to this
63 * function for remote-shell connections is do_cmd().
65 * After negotiating which module to use and reading the server's
66 * motd, this hands over to client_run(). Telling the server the
67 * module will cause it to chroot/setuid/etc.
69 * Instead of doing a transfer, the client may at this stage instead
70 * get a listing of remote modules and exit.
72 * @return -1 for error in startup, or the result of client_run().
73 * Either way, it eventually gets passed to exit_cleanup().
75 int start_socket_client(char *host, char *path, int argc, char *argv[])
78 char *p, *user = NULL;
80 /* This is redundant with code in start_inband_exchange(), but this
81 * short-circuits a problem in the client before we open a socket,
82 * and the extra check won't hurt. */
85 "ERROR: The remote path must start with a module name not a /\n");
89 if ((p = strrchr(host, '@')) != NULL) {
95 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
98 exit_cleanup(RERR_SOCKETIO);
100 ret = start_inband_exchange(user, path, fd, fd, argc);
102 return ret ? ret : client_run(fd, fd, -1, argc, argv);
105 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
109 char *sargs[MAX_ARGS];
111 char line[MAXPATHLEN];
114 if (argc == 0 && !am_sender)
119 "ERROR: The remote path must start with a module name\n");
124 user = getenv("USER");
126 user = getenv("LOGNAME");
128 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
130 if (!read_line(f_in, line, sizeof line - 1)) {
131 rprintf(FERROR, "rsync: did not see server greeting\n");
135 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
136 /* note that read_line strips of \n or \r */
137 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
141 if (protocol_version > remote_protocol)
142 protocol_version = remote_protocol;
144 if (list_only && protocol_version >= 29)
147 /* set daemon_over_rsh to false since we need to build the
148 * true set of args passed through the rsh/ssh connection;
149 * this is a no-op for direct-socket-connection mode */
151 server_options(sargs, &sargc);
153 sargs[sargc++] = ".";
156 sargs[sargc++] = path;
161 print_child_argv(sargs);
163 p = strchr(path,'/');
165 io_printf(f_out, "%s\n", path);
168 /* Old servers may just drop the connection here,
169 rather than sending a proper EXIT command. Yuck. */
170 kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
173 if (!read_line(f_in, line, sizeof line - 1)) {
174 rprintf(FERROR, "rsync: didn't get server startup line\n");
178 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
179 auth_client(f_out, user, line+18);
183 if (strcmp(line,"@RSYNCD: OK") == 0)
186 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
187 /* This is sent by recent versions of the
188 * server to terminate the listing of modules.
189 * We don't want to go on and transfer
190 * anything; just exit. */
194 if (strncmp(line, "@ERROR", 6) == 0) {
195 rprintf(FERROR, "%s\n", line);
196 /* This is always fatal; the server will now
197 * close the socket. */
201 rprintf(FINFO, "%s\n", line);
203 kluge_around_eof = 0;
205 for (i = 0; i < sargc; i++) {
206 io_printf(f_out, "%s\n", sargs[i]);
208 io_printf(f_out, "\n");
210 if (protocol_version < 23) {
211 if (protocol_version == 22 || !am_sender)
212 io_start_multiplex_in();
220 static int rsync_module(int f_in, int f_out, int i)
226 char line[MAXPATHLEN];
227 uid_t uid = (uid_t)-2; /* canonically "nobody" */
228 gid_t gid = (gid_t)-2;
230 char *addr = client_addr(f_in);
231 char *host = client_name(f_in);
232 char *name = lp_name(i);
233 int use_chroot = lp_use_chroot(i);
236 char *request = NULL;
238 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
239 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
242 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
245 "@ERROR: access denied to %s from %s (%s)\n",
251 if (am_daemon && am_server) {
252 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
256 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
258 rsyserr(FLOG, errno, "failed to open lock file %s",
259 safe_fname(lp_lock_file(i)));
260 io_printf(f_out, "@ERROR: failed to open lock file\n");
262 rprintf(FLOG, "max connections (%d) reached\n",
263 lp_max_connections(i));
264 io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
265 lp_max_connections(i));
270 auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
273 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
282 if (lp_transfer_logging(i)) {
283 if (log_format_has(lp_log_format(i), 'i'))
284 daemon_log_format_has_i = 1;
285 if (daemon_log_format_has_i
286 || log_format_has(lp_log_format(i), 'o'))
287 daemon_log_format_has_o_or_i = 1;
290 am_root = (MY_UID() == 0);
294 if (!name_to_uid(p, &uid)) {
295 if (!isdigit(*(unsigned char *)p)) {
296 rprintf(FLOG, "Invalid uid %s\n", p);
297 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
304 if (!name_to_gid(p, &gid)) {
305 if (!isdigit(*(unsigned char *)p)) {
306 rprintf(FLOG, "Invalid gid %s\n", p);
307 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
314 /* TODO: If we're not root, but the configuration requests
315 * that we change to some uid other than the current one, then
318 /* TODO: Perhaps take a list of gids, and make them into the
319 * supplementary groups. */
321 if (use_chroot || (module_dirlen = strlen(lp_path(i))) == 1) {
323 set_filter_dir("/", 1);
325 set_filter_dir(lp_path(i), module_dirlen);
328 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
331 p = lp_include_from(i);
332 parse_filter_file(&server_filter_list, p, MATCHFLG_INCLUDE,
333 XFLG_ANCHORED2ABS | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
336 parse_rule(&server_filter_list, p,
337 MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT,
338 XFLG_ANCHORED2ABS | XFLG_OLD_PREFIXES);
340 p = lp_exclude_from(i);
341 parse_filter_file(&server_filter_list, p, 0,
342 XFLG_ANCHORED2ABS | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
345 parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT,
346 XFLG_ANCHORED2ABS | XFLG_OLD_PREFIXES);
352 * XXX: The 'use chroot' flag is a fairly reliable
353 * source of confusion, because it fails under two
354 * important circumstances: running as non-root,
355 * running on Win32 (or possibly others). On the
356 * other hand, if you are running as root, then it
357 * might be better to always use chroot.
359 * So, perhaps if we can't chroot we should just issue
360 * a warning, unless a "require chroot" flag is set,
361 * in which case we fail.
363 if (chroot(lp_path(i))) {
364 rsyserr(FLOG, errno, "chroot %s failed",
365 safe_fname(lp_path(i)));
366 io_printf(f_out, "@ERROR: chroot failed\n");
370 if (!push_dir("/")) {
371 rsyserr(FLOG, errno, "chdir %s failed\n",
372 safe_fname(lp_path(i)));
373 io_printf(f_out, "@ERROR: chdir failed\n");
378 if (!push_dir(lp_path(i))) {
379 rsyserr(FLOG, errno, "chdir %s failed\n",
380 safe_fname(lp_path(i)));
381 io_printf(f_out, "@ERROR: chdir failed\n");
388 /* XXXX: You could argue that if the daemon is started
389 * by a non-root user and they explicitly specify a
390 * gid, then we should try to change to that gid --
391 * this could be possible if it's already in their
392 * supplementary groups. */
394 /* TODO: Perhaps we need to document that if rsyncd is
395 * started by somebody other than root it will inherit
396 * all their supplementary groups. */
399 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
400 io_printf(f_out, "@ERROR: setgid failed\n");
403 #ifdef HAVE_SETGROUPS
404 /* Get rid of any supplementary groups this process
405 * might have inheristed. */
406 if (setgroups(1, &gid)) {
407 rsyserr(FLOG, errno, "setgroups failed");
408 io_printf(f_out, "@ERROR: setgroups failed\n");
414 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
415 io_printf(f_out, "@ERROR: setuid failed\n");
419 am_root = (MY_UID() == 0);
422 io_printf(f_out, "@RSYNCD: OK\n");
425 if (!(argv = new_array(char *, maxargs)))
426 out_of_memory("rsync_module");
427 argv[argc++] = "rsyncd";
430 if (!read_line(f_in, line, sizeof line - 1))
438 if (argc == maxargs) {
440 if (!(argv = realloc_array(argv, char *, maxargs)))
441 out_of_memory("rsync_module");
443 if (!(argv[argc] = strdup(p)))
444 out_of_memory("rsync_module");
447 if (start_glob == 1) {
451 glob_expand(name, &argv, &argc, &maxargs);
455 if (strcmp(line, ".") == 0)
459 verbose = 0; /* future verbosity is controlled by client options */
461 ret = parse_arguments(&argc, (const char ***) &argp, 0);
463 if (filesfrom_fd == 0)
468 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
469 am_sender ? "on" : "to",
470 request, auth_user, host, addr);
472 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
473 am_sender ? "on" : "to",
474 request, host, addr);
480 /* don't allow the logs to be flooded too fast */
481 if (verbose > lp_max_verbosity(i))
482 verbose = lp_max_verbosity(i);
485 if (protocol_version < 23
486 && (protocol_version == 22 || am_sender))
487 io_start_multiplex_out();
489 /* We have to get I/O multiplexing started so that we can
490 * get the error back to the client. This means getting
491 * the protocol setup finished first in later versions. */
492 setup_protocol(f_out, f_in);
494 /* Since we failed in our option parsing, we may not
495 * have finished parsing that the client sent us a
496 * --files-from option, so look for it manually.
497 * Without this, the socket would be in the wrong
498 * state for the upcoming error message. */
501 for (i = 0; i < argc; i++) {
502 if (strncmp(argv[i], "--files-from", 12) == 0) {
509 write_byte(f_out, 0);
511 io_start_multiplex_out();
517 exit_cleanup(RERR_UNSUPPORTED);
520 if (lp_timeout(i) && lp_timeout(i) > io_timeout)
521 set_io_timeout(lp_timeout(i));
523 start_server(f_in, f_out, argc, argp);
528 /* send a list of available modules to the client. Don't list those
529 with "list = False". */
530 static void send_listing(int fd)
532 int n = lp_numservices();
535 for (i = 0; i < n; i++) {
537 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
540 if (protocol_version >= 25)
541 io_printf(fd,"@RSYNCD: EXIT\n");
544 /* this is called when a connection is established to a client
545 and we want to start talking. The setup of the system is done from
547 int start_daemon(int f_in, int f_out)
553 io_set_sock_fds(f_in, f_out);
555 if (!lp_load(config_file, 0))
556 exit_cleanup(RERR_SYNTAX);
561 set_socket_options(f_in, "SO_KEEPALIVE");
562 set_socket_options(f_in, lp_socket_options());
563 set_nonblocking(f_in);
566 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
568 motd = lp_motd_file();
570 FILE *f = fopen(motd,"r");
571 while (f && !feof(f)) {
572 int len = fread(line, 1, sizeof line - 1, f);
575 io_printf(f_out, "%s", line);
580 io_printf(f_out, "\n");
583 if (!read_line(f_in, line, sizeof line - 1))
586 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
587 io_printf(f_out, "@ERROR: protocol startup error\n");
590 if (protocol_version > remote_protocol)
591 protocol_version = remote_protocol;
594 if (!read_line(f_in, line, sizeof line - 1))
597 if (!*line || strcmp(line, "#list") == 0) {
603 /* it's some sort of command that I don't understand */
604 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
608 if ((i = lp_number(line)) < 0) {
609 char *addr = client_addr(f_in);
610 char *host = client_name(f_in);
611 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
613 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
617 return rsync_module(f_in, f_out, i);
621 int daemon_main(void)
625 if (is_a_socket(STDIN_FILENO)) {
628 /* we are running via inetd - close off stdout and
629 * stderr so that library functions (and getopt) don't
630 * try to use them. Redirect them to /dev/null */
631 for (i = 1; i < 3; i++) {
633 open("/dev/null", O_RDWR);
636 return start_daemon(STDIN_FILENO, STDIN_FILENO);
642 if (!lp_load(config_file, 1))
643 exit_cleanup(RERR_SYNTAX);
645 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
646 rsync_port = RSYNC_PORT;
647 if (bind_address == NULL && *lp_bind_address())
648 bind_address = lp_bind_address();
652 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
653 RSYNC_VERSION, rsync_port);
654 /* TODO: If listening on a particular address, then show that
655 * address too. In fact, why not just do inet_ntop on the
656 * local address??? */
658 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
661 pid_t pid = getpid();
662 cleanup_set_pid(pid);
663 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
664 0666 & ~orig_umask)) == -1) {
666 rsyserr(FLOG, errno, "failed to create pid file %s",
667 safe_fname(pid_file));
668 exit_cleanup(RERR_FILEIO);
670 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
671 write(fd, pidbuf, strlen(pidbuf));
675 start_accept_loop(rsync_port, start_daemon);