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
33 extern int rsync_port;
35 extern int sanitize_paths;
38 * Run a client connected to an rsyncd. The alternative to this
39 * function for remote-shell connections is do_cmd().
41 * After negotiating which module to use and reading the server's
42 * motd, this hands over to client_run(). Telling the server the
43 * module will cause it to chroot/setuid/etc.
45 * Instead of doing a transfer, the client may at this stage instead
46 * get a listing of remote modules and exit.
48 * @return -1 for error in startup, or the result of client_run().
49 * Either way, it eventually gets passed to exit_cleanup().
51 int start_socket_client(char *host, char *path, int argc, char *argv[])
55 extern char *bind_address;
56 extern int default_af_hint;
58 /* this is redundant with code in start_inband_exchange(), but
59 this short-circuits a problem before we open a socket, and
60 the extra check won't hurt */
62 rprintf(FERROR,"ERROR: The remote path must start with a module name not a /\n");
66 p = strchr(host, '@');
74 /* FIXME: If we're going to use a socket program for
75 * testing, then this message is wrong. We need to
76 * say something like "(except really using %s)" */
77 rprintf(FINFO, "opening tcp connection to %s port %d\n",
80 fd = open_socket_out_wrapped (host, rsync_port, bind_address,
83 exit_cleanup(RERR_SOCKETIO);
86 ret = start_inband_exchange(user, path, fd, fd, argc);
88 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
91 int start_inband_exchange(char *user, char *path, int f_in, int f_out, int argc)
94 char *sargs[MAX_ARGS];
96 char line[MAXPATHLEN];
98 extern int remote_version;
99 extern int kludge_around_eof;
100 extern int am_sender;
101 extern int daemon_over_rsh;
102 extern int list_only;
104 if (argc == 0 && !am_sender)
108 rprintf(FERROR, "ERROR: The remote path must start with a module name\n");
112 if (!user) user = getenv("USER");
113 if (!user) user = getenv("LOGNAME");
115 /* set daemon_over_rsh to false since we need to build the
116 true set of args passed through the rsh/ssh connection;
117 this is a no-op for direct-socket-connection mode */
119 server_options(sargs, &sargc);
121 sargs[sargc++] = ".";
124 sargs[sargc++] = path;
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_version) != 1) {
136 /* note that read_line strips of \n or \r */
137 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
142 p = strchr(path,'/');
144 io_printf(f_out, "%s\n", path);
147 /* Old servers may just drop the connection here,
148 rather than sending a proper EXIT command. Yuck. */
149 kludge_around_eof = list_only && (remote_version < 25);
152 if (!read_line(f_in, line, sizeof(line)-1)) {
153 rprintf(FERROR, "rsync: didn't get server startup line\n");
157 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
158 auth_client(f_out, user, line+18);
162 if (strcmp(line,"@RSYNCD: OK") == 0) break;
164 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
165 /* This is sent by recent versions of the
166 * server to terminate the listing of modules.
167 * We don't want to go on and transfer
168 * anything; just exit. */
172 if (strncmp(line, "@ERROR", 6) == 0) {
173 rprintf(FERROR,"%s\n", line);
174 /* This is always fatal; the server will now
175 * close the socket. */
176 return RERR_STARTCLIENT;
178 rprintf(FINFO,"%s\n", line);
181 kludge_around_eof = False;
183 for (i = 0; i < sargc; i++) {
184 io_printf(f_out, "%s\n", sargs[i]);
186 io_printf(f_out, "\n");
188 if (remote_version < 23) {
189 if (remote_version == 22 || (remote_version > 17 && !am_sender))
190 io_start_multiplex_in(f_in);
198 static int rsync_module(int f_in, int f_out, int i)
201 char *argv[MAX_ARGS];
203 char line[MAXPATHLEN];
204 uid_t uid = (uid_t)-2; /* canonically "nobody" */
205 gid_t gid = (gid_t)-2;
207 char *addr, *host, addr_buf[128];
208 char *name = lp_name(i);
209 int use_chroot = lp_use_chroot(i);
213 extern int am_sender;
214 extern int am_server;
215 extern int am_daemon;
216 extern int remote_version;
219 if (is_a_socket(f_in)) {
220 addr = client_addr(f_in);
221 host = client_name(f_in);
223 char *ssh_client = getenv("SSH_CLIENT");
225 strlcpy(addr_buf, ssh_client, sizeof(addr_buf));
226 /* truncate SSH_CLIENT to just IP address */
227 p = strchr(addr_buf, ' ');
231 host = "remote.shell.connection";
234 host = "remote.shell.connection";
238 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
239 rprintf(FERROR,"rsync denied on module %s from %s (%s)\n",
241 io_printf(f_out, "@ERROR: access denied to %s from %s (%s)\n",
246 if (am_daemon && am_server) {
247 rprintf(FINFO, "rsync allowed access on module %s from %s (%s)\n",
251 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
253 rprintf(FERROR,"failed to open lock file %s : %s\n",
254 lp_lock_file(i), strerror(errno));
255 io_printf(f_out, "@ERROR: failed to open lock file %s : %s\n",
256 lp_lock_file(i), strerror(errno));
258 rprintf(FERROR,"max connections (%d) reached\n",
259 lp_max_connections(i));
260 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n", lp_max_connections(i));
266 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
269 rprintf(FERROR,"auth failed on module %s from %s (%s)\n",
271 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
277 am_root = (getuid() == 0);
281 if (!name_to_uid(p, &uid)) {
282 if (!isdigit(* (unsigned char *) p)) {
283 rprintf(FERROR,"Invalid uid %s\n", p);
284 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
291 if (!name_to_gid(p, &gid)) {
292 if (!isdigit(* (unsigned char *) p)) {
293 rprintf(FERROR,"Invalid gid %s\n", p);
294 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
301 /* TODO: If we're not root, but the configuration requests
302 * that we change to some uid other than the current one, then
305 /* TODO: Perhaps take a list of gids, and make them into the
306 * supplementary groups. */
308 p = lp_include_from(i);
309 add_exclude_file(p, 1, 1);
314 p = lp_exclude_from(i);
315 add_exclude_file(p, 1, 0);
324 * XXX: The 'use chroot' flag is a fairly reliable
325 * source of confusion, because it fails under two
326 * important circumstances: running as non-root,
327 * running on Win32 (or possibly others). On the
328 * other hand, if you are running as root, then it
329 * might be better to always use chroot.
331 * So, perhaps if we can't chroot we should just issue
332 * a warning, unless a "require chroot" flag is set,
333 * in which case we fail.
335 if (chroot(lp_path(i))) {
336 rsyserr(FERROR, errno, "chroot %s failed", lp_path(i));
337 io_printf(f_out, "@ERROR: chroot failed\n");
341 if (!push_dir("/", 0)) {
342 rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i));
343 io_printf(f_out, "@ERROR: chdir failed\n");
348 if (!push_dir(lp_path(i), 0)) {
349 rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i));
350 io_printf(f_out, "@ERROR: chdir failed\n");
357 #ifdef HAVE_SETGROUPS
358 /* Get rid of any supplementary groups this process
359 * might have inheristed. */
360 if (setgroups(0, NULL)) {
361 rsyserr(FERROR, errno, "setgroups failed");
362 io_printf(f_out, "@ERROR: setgroups failed\n");
367 /* XXXX: You could argue that if the daemon is started
368 * by a non-root user and they explicitly specify a
369 * gid, then we should try to change to that gid --
370 * this could be possible if it's already in their
371 * supplementary groups. */
373 /* TODO: Perhaps we need to document that if rsyncd is
374 * started by somebody other than root it will inherit
375 * all their supplementary groups. */
378 rsyserr(FERROR, errno, "setgid %d failed", (int) gid);
379 io_printf(f_out, "@ERROR: setgid failed\n");
384 rsyserr(FERROR, errno, "setuid %d failed", (int) uid);
385 io_printf(f_out, "@ERROR: setuid failed\n");
389 am_root = (getuid() == 0);
392 io_printf(f_out, "@RSYNCD: OK\n");
394 argv[argc++] = "rsyncd";
397 if (!read_line(f_in, line, sizeof(line)-1)) {
405 argv[argc] = strdup(p);
411 if (start_glob == 1) {
415 glob_expand(name, argv, &argc, MAX_ARGS);
420 if (strcmp(line,".") == 0) {
424 if (argc == MAX_ARGS) {
429 if (sanitize_paths) {
431 * Note that this is applied to all parameters, whether or not
432 * they are filenames, but no other legal parameters contain
433 * the forms that need to be sanitized so it doesn't hurt;
434 * it is not known at this point which parameters are files
437 for (i = 1; i < argc; i++) {
438 sanitize_path(argv[i], NULL);
443 ret = parse_arguments(&argc, (const char ***) &argp, 0);
447 rprintf(FINFO,"rsync %s %s from %s@%s (%s)\n",
449 request, auth_user, host, addr);
451 rprintf(FINFO,"rsync %s %s from %s (%s)\n",
453 request, host, addr);
459 /* don't allow the logs to be flooded too fast */
460 if (verbose > 1) verbose = 1;
463 if (remote_version < 23) {
464 if (remote_version == 22 || (remote_version > 17 && am_sender))
465 io_start_multiplex_out(f_out);
468 /* For later protocol versions, we don't start multiplexing
469 * until we've configured nonblocking in start_server. That
470 * means we're in a sticky situation now: there's no way to
471 * convey errors to the client. */
473 /* FIXME: Hold off on reporting option processing errors until
474 * we've set up nonblocking and multiplexed IO and can get the
475 * message back to them. */
478 exit_cleanup(RERR_UNSUPPORTED);
482 extern int io_timeout;
483 io_timeout = lp_timeout(i);
486 start_server(f_in, f_out, argc, argp);
491 /* send a list of available modules to the client. Don't list those
492 with "list = False". */
493 static void send_listing(int fd)
495 int n = lp_numservices();
497 extern int remote_version;
501 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
503 if (remote_version >= 25)
504 io_printf(fd,"@RSYNCD: EXIT\n");
507 /* this is called when a connection is established to a client
508 and we want to start talking. The setup of the system is done from
510 int start_daemon(int f_in, int f_out)
515 extern char *config_file;
516 extern int remote_version;
517 extern int am_server;
519 if (!lp_load(config_file, 0)) {
520 exit_cleanup(RERR_SYNTAX);
524 set_socket_options(f_in, "SO_KEEPALIVE");
525 set_socket_options(f_in, lp_socket_options());
526 set_nonblocking(f_in);
529 io_printf(f_out, "@RSYNCD: %d\n", PROTOCOL_VERSION);
531 motd = lp_motd_file();
533 FILE *f = fopen(motd,"r");
534 while (f && !feof(f)) {
535 int len = fread(line, 1, sizeof(line)-1, f);
538 io_printf(f_out, "%s", line);
542 io_printf(f_out, "\n");
545 if (!read_line(f_in, line, sizeof(line)-1)) {
549 if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) {
550 io_printf(f_out, "@ERROR: protocol startup error\n");
556 if (!read_line(f_in, line, sizeof(line)-1)) {
560 if (!*line || strcmp(line,"#list")==0) {
566 /* it's some sort of command that I don't understand */
567 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
573 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
578 return rsync_module(f_in, f_out, i);
582 int daemon_main(void)
584 extern char *config_file;
585 extern int orig_umask;
587 extern int no_detach;
589 if (is_a_socket(STDIN_FILENO)) {
592 /* we are running via inetd - close off stdout and
593 stderr so that library functions (and getopt) don't
594 try to use them. Redirect them to /dev/null */
597 open("/dev/null", O_RDWR);
600 return start_daemon(STDIN_FILENO, STDIN_FILENO);
606 if (!lp_load(config_file, 1)) {
607 exit_cleanup(RERR_SYNTAX);
612 rprintf(FINFO, "rsyncd version %s starting, listening on port %d\n",
615 /* TODO: If listening on a particular address, then show that
616 * address too. In fact, why not just do inet_ntop on the
617 * local address??? */
619 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
622 int pid = (int) getpid();
623 cleanup_set_pid(pid);
624 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
625 0666 & ~orig_umask)) == -1) {
627 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
628 exit_cleanup(RERR_FILEIO);
630 snprintf(pidbuf, sizeof(pidbuf), "%d\n", pid);
631 write(fd, pidbuf, strlen(pidbuf));
635 start_accept_loop(rsync_port, start_daemon);