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 orig_umask;
48 extern int default_af_hint;
49 extern char *bind_address;
50 extern struct exclude_list_struct server_exclude_list;
51 extern char *exclude_path_prefix;
52 extern char *config_file;
53 extern char *files_from;
58 * Run a client connected to an rsyncd. The alternative to this
59 * function for remote-shell connections is do_cmd().
61 * After negotiating which module to use and reading the server's
62 * motd, this hands over to client_run(). Telling the server the
63 * module will cause it to chroot/setuid/etc.
65 * Instead of doing a transfer, the client may at this stage instead
66 * get a listing of remote modules and exit.
68 * @return -1 for error in startup, or the result of client_run().
69 * Either way, it eventually gets passed to exit_cleanup().
71 int start_socket_client(char *host, char *path, int argc, char *argv[])
74 char *p, *user = NULL;
76 /* This is redundant with code in start_inband_exchange(), but this
77 * short-circuits a problem in the client before we open a socket,
78 * and the extra check won't hurt. */
81 "ERROR: The remote path must start with a module name not a /\n");
85 if ((p = strchr(host, '@')) != NULL) {
91 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
94 exit_cleanup(RERR_SOCKETIO);
96 ret = start_inband_exchange(user, path, fd, fd, argc);
98 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
101 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
105 char *sargs[MAX_ARGS];
107 char line[MAXPATHLEN];
110 if (argc == 0 && !am_sender)
115 "ERROR: The remote path must start with a module name\n");
120 user = getenv("USER");
122 user = getenv("LOGNAME");
124 /* set daemon_over_rsh to false since we need to build the
125 * true set of args passed through the rsh/ssh connection;
126 * this is a no-op for direct-socket-connection mode */
128 server_options(sargs, &sargc);
130 sargs[sargc++] = ".";
133 sargs[sargc++] = path;
137 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
139 if (!read_line(f_in, line, sizeof line - 1)) {
140 rprintf(FERROR, "rsync: did not see server greeting\n");
144 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
145 /* note that read_line strips of \n or \r */
146 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
150 if (protocol_version > remote_protocol)
151 protocol_version = remote_protocol;
153 p = strchr(path,'/');
155 io_printf(f_out, "%s\n", path);
158 /* Old servers may just drop the connection here,
159 rather than sending a proper EXIT command. Yuck. */
160 kludge_around_eof = list_only && (protocol_version < 25);
163 if (!read_line(f_in, line, sizeof line - 1)) {
164 rprintf(FERROR, "rsync: didn't get server startup line\n");
168 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
169 auth_client(f_out, user, line+18);
173 if (strcmp(line,"@RSYNCD: OK") == 0)
176 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
177 /* This is sent by recent versions of the
178 * server to terminate the listing of modules.
179 * We don't want to go on and transfer
180 * anything; just exit. */
184 if (strncmp(line, "@ERROR", 6) == 0) {
185 rprintf(FERROR, "%s\n", line);
186 /* This is always fatal; the server will now
187 * close the socket. */
188 return RERR_STARTCLIENT;
190 rprintf(FINFO,"%s\n", line);
193 kludge_around_eof = False;
195 for (i = 0; i < sargc; i++) {
196 io_printf(f_out, "%s\n", sargs[i]);
198 io_printf(f_out, "\n");
200 if (protocol_version < 23) {
201 if (protocol_version == 22 || !am_sender)
202 io_start_multiplex_in();
210 static int rsync_module(int f_in, int f_out, int i)
216 char line[MAXPATHLEN];
217 uid_t uid = (uid_t)-2; /* canonically "nobody" */
218 gid_t gid = (gid_t)-2;
220 char *addr = client_addr(f_in);
221 char *host = client_name(f_in);
222 char *name = lp_name(i);
223 int use_chroot = lp_use_chroot(i);
226 char *request = NULL;
228 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
229 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
232 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
235 "@ERROR: access denied to %s from %s (%s)\n",
241 if (am_daemon && am_server) {
242 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
246 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
248 rsyserr(FLOG, errno, "failed to open lock file %s",
250 io_printf(f_out, "@ERROR: failed to open lock file %s\n",
253 rprintf(FLOG, "max connections (%d) reached\n",
254 lp_max_connections(i));
255 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n",
256 lp_max_connections(i));
261 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
264 rprintf(FLOG, "auth failed on module %s from %s (%s)\n",
266 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
272 am_root = (MY_UID() == 0);
276 if (!name_to_uid(p, &uid)) {
277 if (!isdigit(*(unsigned char *)p)) {
278 rprintf(FLOG, "Invalid uid %s\n", p);
279 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
286 if (!name_to_gid(p, &gid)) {
287 if (!isdigit(*(unsigned char *)p)) {
288 rprintf(FLOG, "Invalid gid %s\n", p);
289 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
296 /* TODO: If we're not root, but the configuration requests
297 * that we change to some uid other than the current one, then
300 /* TODO: Perhaps take a list of gids, and make them into the
301 * supplementary groups. */
303 exclude_path_prefix = use_chroot? "" : lp_path(i);
304 if (*exclude_path_prefix == '/' && !exclude_path_prefix[1])
305 exclude_path_prefix = "";
307 p = lp_include_from(i);
308 add_exclude_file(&server_exclude_list, p,
309 XFLG_FATAL_ERRORS | XFLG_DEF_INCLUDE);
312 add_exclude(&server_exclude_list, p,
313 XFLG_WORD_SPLIT | XFLG_DEF_INCLUDE);
315 p = lp_exclude_from(i);
316 add_exclude_file(&server_exclude_list, p,
320 add_exclude(&server_exclude_list, p, XFLG_WORD_SPLIT);
322 exclude_path_prefix = NULL;
328 * XXX: The 'use chroot' flag is a fairly reliable
329 * source of confusion, because it fails under two
330 * important circumstances: running as non-root,
331 * running on Win32 (or possibly others). On the
332 * other hand, if you are running as root, then it
333 * might be better to always use chroot.
335 * So, perhaps if we can't chroot we should just issue
336 * a warning, unless a "require chroot" flag is set,
337 * in which case we fail.
339 if (chroot(lp_path(i))) {
340 rsyserr(FLOG, errno, "chroot %s failed", lp_path(i));
341 io_printf(f_out, "@ERROR: chroot failed\n");
345 if (!push_dir("/")) {
346 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
347 io_printf(f_out, "@ERROR: chdir failed\n");
352 if (!push_dir(lp_path(i))) {
353 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
354 io_printf(f_out, "@ERROR: chdir failed\n");
361 /* XXXX: You could argue that if the daemon is started
362 * by a non-root user and they explicitly specify a
363 * gid, then we should try to change to that gid --
364 * this could be possible if it's already in their
365 * supplementary groups. */
367 /* TODO: Perhaps we need to document that if rsyncd is
368 * started by somebody other than root it will inherit
369 * all their supplementary groups. */
372 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
373 io_printf(f_out, "@ERROR: setgid failed\n");
376 #ifdef HAVE_SETGROUPS
377 /* Get rid of any supplementary groups this process
378 * might have inheristed. */
379 if (setgroups(1, &gid)) {
380 rsyserr(FLOG, errno, "setgroups failed");
381 io_printf(f_out, "@ERROR: setgroups failed\n");
387 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
388 io_printf(f_out, "@ERROR: setuid failed\n");
392 am_root = (MY_UID() == 0);
395 io_printf(f_out, "@RSYNCD: OK\n");
398 if (!(argv = new_array(char *, maxargs)))
399 out_of_memory("rsync_module");
400 argv[argc++] = "rsyncd";
403 if (!read_line(f_in, line, sizeof line - 1))
411 if (argc == maxargs) {
413 if (!(argv = realloc_array(argv, char *, maxargs)))
414 out_of_memory("rsync_module");
416 if (!(argv[argc] = strdup(p)))
417 out_of_memory("rsync_module");
420 if (start_glob == 1) {
424 glob_expand(name, &argv, &argc, &maxargs);
428 if (strcmp(line, ".") == 0)
433 ret = parse_arguments(&argc, (const char ***) &argp, 0);
435 if (filesfrom_fd == 0)
440 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
441 am_sender ? "on" : "to",
442 request, auth_user, host, addr);
444 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
445 am_sender ? "on" : "to",
446 request, host, addr);
452 /* don't allow the logs to be flooded too fast */
453 if (verbose > lp_max_verbosity())
454 verbose = lp_max_verbosity();
457 if (protocol_version < 23
458 && (protocol_version == 22 || am_sender))
459 io_start_multiplex_out();
461 /* We have to get I/O multiplexing started so that we can
462 * get the error back to the client. This means getting
463 * the protocol setup finished first in later versions. */
464 setup_protocol(f_out, f_in);
465 if (files_from && !am_sender && strcmp(files_from, "-") != 0)
466 write_byte(f_out, 0);
467 io_start_multiplex_out();
473 exit_cleanup(RERR_UNSUPPORTED);
477 io_timeout = lp_timeout(i);
479 start_server(f_in, f_out, argc, argp);
484 /* send a list of available modules to the client. Don't list those
485 with "list = False". */
486 static void send_listing(int fd)
488 int n = lp_numservices();
491 for (i = 0; i < n; i++) {
493 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
496 if (protocol_version >= 25)
497 io_printf(fd,"@RSYNCD: EXIT\n");
500 /* this is called when a connection is established to a client
501 and we want to start talking. The setup of the system is done from
503 int start_daemon(int f_in, int f_out)
509 io_set_sock_fds(f_in, f_out);
511 if (!lp_load(config_file, 0))
512 exit_cleanup(RERR_SYNTAX);
517 set_socket_options(f_in, "SO_KEEPALIVE");
518 set_socket_options(f_in, lp_socket_options());
519 set_nonblocking(f_in);
522 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
524 motd = lp_motd_file();
526 FILE *f = fopen(motd,"r");
527 while (f && !feof(f)) {
528 int len = fread(line, 1, sizeof line - 1, f);
531 io_printf(f_out, "%s", line);
536 io_printf(f_out, "\n");
539 if (!read_line(f_in, line, sizeof line - 1))
542 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
543 io_printf(f_out, "@ERROR: protocol startup error\n");
546 if (protocol_version > remote_protocol)
547 protocol_version = remote_protocol;
550 if (!read_line(f_in, line, sizeof line - 1))
553 if (!*line || strcmp(line, "#list") == 0) {
559 /* it's some sort of command that I don't understand */
560 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
564 if ((i = lp_number(line)) < 0) {
565 char *addr = client_addr(f_in);
566 char *host = client_name(f_in);
567 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
569 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
573 return rsync_module(f_in, f_out, i);
577 int daemon_main(void)
581 if (is_a_socket(STDIN_FILENO)) {
584 /* we are running via inetd - close off stdout and
585 * stderr so that library functions (and getopt) don't
586 * try to use them. Redirect them to /dev/null */
587 for (i = 1; i < 3; i++) {
589 open("/dev/null", O_RDWR);
592 return start_daemon(STDIN_FILENO, STDIN_FILENO);
598 if (!lp_load(config_file, 1))
599 exit_cleanup(RERR_SYNTAX);
603 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
604 RSYNC_VERSION, rsync_port);
605 /* TODO: If listening on a particular address, then show that
606 * address too. In fact, why not just do inet_ntop on the
607 * local address??? */
609 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
612 pid_t pid = getpid();
613 cleanup_set_pid(pid);
614 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
615 0666 & ~orig_umask)) == -1) {
617 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
618 exit_cleanup(RERR_FILEIO);
620 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
621 write(fd, pidbuf, strlen(pidbuf));
625 start_accept_loop(rsync_port, start_daemon);