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;
57 * Run a client connected to an rsyncd. The alternative to this
58 * function for remote-shell connections is do_cmd().
60 * After negotiating which module to use and reading the server's
61 * motd, this hands over to client_run(). Telling the server the
62 * module will cause it to chroot/setuid/etc.
64 * Instead of doing a transfer, the client may at this stage instead
65 * get a listing of remote modules and exit.
67 * @return -1 for error in startup, or the result of client_run().
68 * Either way, it eventually gets passed to exit_cleanup().
70 int start_socket_client(char *host, char *path, int argc, char *argv[])
73 char *p, *user = NULL;
75 /* This is redundant with code in start_inband_exchange(), but this
76 * short-circuits a problem in the client before we open a socket,
77 * and the extra check won't hurt. */
80 "ERROR: The remote path must start with a module name not a /\n");
84 if ((p = strchr(host, '@')) != NULL) {
90 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
93 exit_cleanup(RERR_SOCKETIO);
95 ret = start_inband_exchange(user, path, fd, fd, argc);
97 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
100 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
104 char *sargs[MAX_ARGS];
106 char line[MAXPATHLEN];
109 if (argc == 0 && !am_sender)
114 "ERROR: The remote path must start with a module name\n");
119 user = getenv("USER");
121 user = getenv("LOGNAME");
123 /* set daemon_over_rsh to false since we need to build the
124 * true set of args passed through the rsh/ssh connection;
125 * this is a no-op for direct-socket-connection mode */
127 server_options(sargs, &sargc);
129 sargs[sargc++] = ".";
132 sargs[sargc++] = path;
136 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
138 if (!read_line(f_in, line, sizeof line - 1)) {
139 rprintf(FERROR, "rsync: did not see server greeting\n");
143 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
144 /* note that read_line strips of \n or \r */
145 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
149 if (protocol_version > remote_protocol)
150 protocol_version = remote_protocol;
152 p = strchr(path,'/');
154 io_printf(f_out, "%s\n", path);
157 /* Old servers may just drop the connection here,
158 rather than sending a proper EXIT command. Yuck. */
159 kludge_around_eof = list_only && (protocol_version < 25);
162 if (!read_line(f_in, line, sizeof line - 1)) {
163 rprintf(FERROR, "rsync: didn't get server startup line\n");
167 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
168 auth_client(f_out, user, line+18);
172 if (strcmp(line,"@RSYNCD: OK") == 0)
175 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
176 /* This is sent by recent versions of the
177 * server to terminate the listing of modules.
178 * We don't want to go on and transfer
179 * anything; just exit. */
183 if (strncmp(line, "@ERROR", 6) == 0) {
184 rprintf(FERROR, "%s\n", line);
185 /* This is always fatal; the server will now
186 * close the socket. */
187 return RERR_STARTCLIENT;
189 rprintf(FINFO,"%s\n", line);
192 kludge_around_eof = False;
194 for (i = 0; i < sargc; i++) {
195 io_printf(f_out, "%s\n", sargs[i]);
197 io_printf(f_out, "\n");
199 if (protocol_version < 23) {
200 if (protocol_version == 22 || !am_sender)
201 io_start_multiplex_in();
209 static int rsync_module(int f_in, int f_out, int i)
215 char line[MAXPATHLEN];
216 uid_t uid = (uid_t)-2; /* canonically "nobody" */
217 gid_t gid = (gid_t)-2;
219 char *addr = client_addr(f_in);
220 char *host = client_name(f_in);
221 char *name = lp_name(i);
222 int use_chroot = lp_use_chroot(i);
225 char *request = NULL;
227 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
228 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
230 io_printf(f_out, "@ERROR: access denied to %s from %s (%s)\n",
235 if (am_daemon && am_server) {
236 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
240 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
242 rsyserr(FLOG, errno, "failed to open lock file %s",
244 io_printf(f_out, "@ERROR: failed to open lock file %s\n",
247 rprintf(FLOG, "max connections (%d) reached\n",
248 lp_max_connections(i));
249 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n",
250 lp_max_connections(i));
255 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
258 rprintf(FLOG, "auth failed on module %s from %s (%s)\n",
260 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
266 am_root = (MY_UID() == 0);
270 if (!name_to_uid(p, &uid)) {
271 if (!isdigit(*(unsigned char *)p)) {
272 rprintf(FLOG, "Invalid uid %s\n", p);
273 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
280 if (!name_to_gid(p, &gid)) {
281 if (!isdigit(*(unsigned char *)p)) {
282 rprintf(FLOG, "Invalid gid %s\n", p);
283 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
290 /* TODO: If we're not root, but the configuration requests
291 * that we change to some uid other than the current one, then
294 /* TODO: Perhaps take a list of gids, and make them into the
295 * supplementary groups. */
297 exclude_path_prefix = use_chroot? "" : lp_path(i);
298 if (*exclude_path_prefix == '/' && !exclude_path_prefix[1])
299 exclude_path_prefix = "";
301 p = lp_include_from(i);
302 add_exclude_file(&server_exclude_list, p,
303 XFLG_FATAL_ERRORS | XFLG_DEF_INCLUDE);
306 add_exclude(&server_exclude_list, p,
307 XFLG_WORD_SPLIT | XFLG_DEF_INCLUDE);
309 p = lp_exclude_from(i);
310 add_exclude_file(&server_exclude_list, p,
314 add_exclude(&server_exclude_list, p, XFLG_WORD_SPLIT);
316 exclude_path_prefix = NULL;
322 * XXX: The 'use chroot' flag is a fairly reliable
323 * source of confusion, because it fails under two
324 * important circumstances: running as non-root,
325 * running on Win32 (or possibly others). On the
326 * other hand, if you are running as root, then it
327 * might be better to always use chroot.
329 * So, perhaps if we can't chroot we should just issue
330 * a warning, unless a "require chroot" flag is set,
331 * in which case we fail.
333 if (chroot(lp_path(i))) {
334 rsyserr(FLOG, errno, "chroot %s failed", lp_path(i));
335 io_printf(f_out, "@ERROR: chroot failed\n");
339 if (!push_dir("/")) {
340 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
341 io_printf(f_out, "@ERROR: chdir failed\n");
346 if (!push_dir(lp_path(i))) {
347 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
348 io_printf(f_out, "@ERROR: chdir failed\n");
355 /* XXXX: You could argue that if the daemon is started
356 * by a non-root user and they explicitly specify a
357 * gid, then we should try to change to that gid --
358 * this could be possible if it's already in their
359 * supplementary groups. */
361 /* TODO: Perhaps we need to document that if rsyncd is
362 * started by somebody other than root it will inherit
363 * all their supplementary groups. */
366 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
367 io_printf(f_out, "@ERROR: setgid failed\n");
370 #ifdef HAVE_SETGROUPS
371 /* Get rid of any supplementary groups this process
372 * might have inheristed. */
373 if (setgroups(1, &gid)) {
374 rsyserr(FLOG, errno, "setgroups failed");
375 io_printf(f_out, "@ERROR: setgroups failed\n");
381 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
382 io_printf(f_out, "@ERROR: setuid failed\n");
386 am_root = (MY_UID() == 0);
389 io_printf(f_out, "@RSYNCD: OK\n");
392 if (!(argv = new_array(char *, maxargs)))
393 out_of_memory("rsync_module");
394 argv[argc++] = "rsyncd";
397 if (!read_line(f_in, line, sizeof line - 1))
405 if (argc == maxargs) {
407 if (!(argv = realloc_array(argv, char *, maxargs)))
408 out_of_memory("rsync_module");
410 if (!(argv[argc] = strdup(p)))
411 out_of_memory("rsync_module");
414 if (start_glob == 1) {
418 glob_expand(name, &argv, &argc, &maxargs);
422 if (strcmp(line, ".") == 0)
427 ret = parse_arguments(&argc, (const char ***) &argp, 0);
429 if (filesfrom_fd == 0)
434 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
435 am_sender ? "on" : "to",
436 request, auth_user, host, addr);
438 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
439 am_sender ? "on" : "to",
440 request, host, addr);
446 /* don't allow the logs to be flooded too fast */
447 if (verbose > lp_max_verbosity())
448 verbose = lp_max_verbosity();
451 if (protocol_version < 23
452 && (protocol_version == 22 || am_sender))
453 io_start_multiplex_out();
455 /* We have to get I/O multiplexing started so that we can
456 * get the error back to the client. This means getting
457 * the protocol setup finished first in later versions. */
458 setup_protocol(f_out, f_in);
459 io_start_multiplex_out();
465 exit_cleanup(RERR_UNSUPPORTED);
469 io_timeout = lp_timeout(i);
471 start_server(f_in, f_out, argc, argp);
476 /* send a list of available modules to the client. Don't list those
477 with "list = False". */
478 static void send_listing(int fd)
480 int n = lp_numservices();
483 for (i = 0; i < n; i++)
485 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
487 if (protocol_version >= 25)
488 io_printf(fd,"@RSYNCD: EXIT\n");
491 /* this is called when a connection is established to a client
492 and we want to start talking. The setup of the system is done from
494 int start_daemon(int f_in, int f_out)
500 io_set_sock_fds(f_in, f_out);
502 if (!lp_load(config_file, 0))
503 exit_cleanup(RERR_SYNTAX);
508 set_socket_options(f_in, "SO_KEEPALIVE");
509 set_socket_options(f_in, lp_socket_options());
510 set_nonblocking(f_in);
513 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
515 motd = lp_motd_file();
517 FILE *f = fopen(motd,"r");
518 while (f && !feof(f)) {
519 int len = fread(line, 1, sizeof line - 1, f);
522 io_printf(f_out, "%s", line);
527 io_printf(f_out, "\n");
530 if (!read_line(f_in, line, sizeof line - 1))
533 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
534 io_printf(f_out, "@ERROR: protocol startup error\n");
537 if (protocol_version > remote_protocol)
538 protocol_version = remote_protocol;
542 if (!read_line(f_in, line, sizeof line - 1))
545 if (!*line || strcmp(line,"#list") == 0) {
551 /* it's some sort of command that I don't understand */
552 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
558 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
563 return rsync_module(f_in, f_out, i);
567 int daemon_main(void)
571 if (is_a_socket(STDIN_FILENO)) {
574 /* we are running via inetd - close off stdout and
575 * stderr so that library functions (and getopt) don't
576 * try to use them. Redirect them to /dev/null */
577 for (i = 1; i < 3; i++) {
579 open("/dev/null", O_RDWR);
582 return start_daemon(STDIN_FILENO, STDIN_FILENO);
588 if (!lp_load(config_file, 1))
589 exit_cleanup(RERR_SYNTAX);
593 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
594 RSYNC_VERSION, rsync_port);
595 /* TODO: If listening on a particular address, then show that
596 * address too. In fact, why not just do inet_ntop on the
597 * local address??? */
599 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
602 pid_t pid = getpid();
603 cleanup_set_pid(pid);
604 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
605 0666 & ~orig_umask)) == -1) {
607 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
608 exit_cleanup(RERR_FILEIO);
610 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
611 write(fd, pidbuf, strlen(pidbuf));
615 start_accept_loop(rsync_port, start_daemon);