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;
36 extern int filesfrom_fd;
37 extern int remote_protocol;
38 extern int protocol_version;
39 extern struct exclude_struct **server_exclude_list;
40 extern char *exclude_path_prefix;
43 * Run a client connected to an rsyncd. The alternative to this
44 * function for remote-shell connections is do_cmd().
46 * After negotiating which module to use and reading the server's
47 * motd, this hands over to client_run(). Telling the server the
48 * module will cause it to chroot/setuid/etc.
50 * Instead of doing a transfer, the client may at this stage instead
51 * get a listing of remote modules and exit.
53 * @return -1 for error in startup, or the result of client_run().
54 * Either way, it eventually gets passed to exit_cleanup().
56 int start_socket_client(char *host, char *path, int argc, char *argv[])
60 extern char *bind_address;
61 extern int default_af_hint;
63 /* this is redundant with code in start_inband_exchange(), but
64 * this short-circuits a problem before we open a socket, and
65 * the extra check won't hurt */
67 rprintf(FERROR,"ERROR: The remote path must start with a module name not a /\n");
71 p = strchr(host, '@');
79 /* FIXME: If we're going to use a socket program for
80 * testing, then this message is wrong. We need to
81 * say something like "(except really using %s)" */
82 rprintf(FINFO, "opening tcp connection to %s port %d\n",
85 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
88 exit_cleanup(RERR_SOCKETIO);
91 ret = start_inband_exchange(user, path, fd, fd, argc);
93 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
96 int start_inband_exchange(char *user, char *path, int f_in, int f_out, int argc)
99 char *sargs[MAX_ARGS];
101 char line[MAXPATHLEN];
103 extern int kludge_around_eof;
104 extern int am_sender;
105 extern int daemon_over_rsh;
106 extern int list_only;
108 if (argc == 0 && !am_sender)
112 rprintf(FERROR, "ERROR: The remote path must start with a module name\n");
116 if (!user) user = getenv("USER");
117 if (!user) user = getenv("LOGNAME");
119 /* set daemon_over_rsh to false since we need to build the
120 * true set of args passed through the rsh/ssh connection;
121 * this is a no-op for direct-socket-connection mode */
123 server_options(sargs, &sargc);
125 sargs[sargc++] = ".";
128 sargs[sargc++] = path;
132 io_printf(f_out, "@RSYNCD: %d\n", PROTOCOL_VERSION);
134 if (!read_line(f_in, line, sizeof(line)-1)) {
135 rprintf(FERROR, "rsync: did not see server greeting\n");
139 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
140 /* note that read_line strips of \n or \r */
141 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
145 if (protocol_version > remote_protocol)
146 protocol_version = remote_protocol;
148 p = strchr(path,'/');
150 io_printf(f_out, "%s\n", path);
153 /* Old servers may just drop the connection here,
154 rather than sending a proper EXIT command. Yuck. */
155 kludge_around_eof = list_only && (protocol_version < 25);
158 if (!read_line(f_in, line, sizeof(line)-1)) {
159 rprintf(FERROR, "rsync: didn't get server startup line\n");
163 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
164 auth_client(f_out, user, line+18);
168 if (strcmp(line,"@RSYNCD: OK") == 0) break;
170 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
171 /* This is sent by recent versions of the
172 * server to terminate the listing of modules.
173 * We don't want to go on and transfer
174 * anything; just exit. */
178 if (strncmp(line, "@ERROR", 6) == 0) {
179 rprintf(FERROR,"%s\n", line);
180 /* This is always fatal; the server will now
181 * close the socket. */
182 return RERR_STARTCLIENT;
184 rprintf(FINFO,"%s\n", line);
187 kludge_around_eof = False;
189 for (i = 0; i < sargc; i++) {
190 io_printf(f_out, "%s\n", sargs[i]);
192 io_printf(f_out, "\n");
194 if (protocol_version < 23) {
195 if (protocol_version == 22 || (protocol_version > 17 && !am_sender))
196 io_start_multiplex_in(f_in);
204 static int rsync_module(int f_in, int f_out, int i)
207 char *argv[MAX_ARGS];
209 char line[MAXPATHLEN];
210 uid_t uid = (uid_t)-2; /* canonically "nobody" */
211 gid_t gid = (gid_t)-2;
213 char *addr = client_addr(f_in);
214 char *host = client_name(f_in);
215 char *name = lp_name(i);
216 int use_chroot = lp_use_chroot(i);
220 extern int am_sender;
221 extern int am_server;
222 extern int am_daemon;
225 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
226 rprintf(FERROR,"rsync denied on module %s from %s (%s)\n",
228 io_printf(f_out, "@ERROR: access denied to %s from %s (%s)\n",
233 if (am_daemon && am_server) {
234 rprintf(FINFO, "rsync allowed access on module %s from %s (%s)\n",
238 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
240 rprintf(FERROR,"failed to open lock file %s : %s\n",
241 lp_lock_file(i), strerror(errno));
242 io_printf(f_out, "@ERROR: failed to open lock file %s : %s\n",
243 lp_lock_file(i), strerror(errno));
245 rprintf(FERROR,"max connections (%d) reached\n",
246 lp_max_connections(i));
247 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n",
248 lp_max_connections(i));
254 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
257 rprintf(FERROR,"auth failed on module %s from %s (%s)\n",
259 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
265 am_root = (getuid() == 0);
269 if (!name_to_uid(p, &uid)) {
270 if (!isdigit(* (unsigned char *) p)) {
271 rprintf(FERROR,"Invalid uid %s\n", p);
272 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
279 if (!name_to_gid(p, &gid)) {
280 if (!isdigit(* (unsigned char *) p)) {
281 rprintf(FERROR,"Invalid gid %s\n", p);
282 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
289 /* TODO: If we're not root, but the configuration requests
290 * that we change to some uid other than the current one, then
293 /* TODO: Perhaps take a list of gids, and make them into the
294 * supplementary groups. */
296 exclude_path_prefix = use_chroot? "" : lp_path(i);
297 if (*exclude_path_prefix == '/' && !exclude_path_prefix[1])
298 exclude_path_prefix = "";
300 p = lp_include_from(i);
301 add_exclude_file(&server_exclude_list, p, MISSING_FATAL, ADD_INCLUDE);
304 add_exclude_line(&server_exclude_list, p, ADD_INCLUDE);
306 p = lp_exclude_from(i);
307 add_exclude_file(&server_exclude_list, p, MISSING_FATAL, ADD_EXCLUDE);
310 add_exclude_line(&server_exclude_list, p, ADD_EXCLUDE);
312 exclude_path_prefix = NULL;
318 * XXX: The 'use chroot' flag is a fairly reliable
319 * source of confusion, because it fails under two
320 * important circumstances: running as non-root,
321 * running on Win32 (or possibly others). On the
322 * other hand, if you are running as root, then it
323 * might be better to always use chroot.
325 * So, perhaps if we can't chroot we should just issue
326 * a warning, unless a "require chroot" flag is set,
327 * in which case we fail.
329 if (chroot(lp_path(i))) {
330 rsyserr(FERROR, errno, "chroot %s failed", lp_path(i));
331 io_printf(f_out, "@ERROR: chroot failed\n");
335 if (!push_dir("/", 0)) {
336 rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i));
337 io_printf(f_out, "@ERROR: chdir failed\n");
342 if (!push_dir(lp_path(i), 0)) {
343 rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i));
344 io_printf(f_out, "@ERROR: chdir failed\n");
351 /* XXXX: You could argue that if the daemon is started
352 * by a non-root user and they explicitly specify a
353 * gid, then we should try to change to that gid --
354 * this could be possible if it's already in their
355 * supplementary groups. */
357 /* TODO: Perhaps we need to document that if rsyncd is
358 * started by somebody other than root it will inherit
359 * all their supplementary groups. */
362 rsyserr(FERROR, errno, "setgid %d failed", (int) gid);
363 io_printf(f_out, "@ERROR: setgid failed\n");
366 #ifdef HAVE_SETGROUPS
367 /* Get rid of any supplementary groups this process
368 * might have inheristed. */
369 if (setgroups(1, &gid)) {
370 rsyserr(FERROR, errno, "setgroups failed");
371 io_printf(f_out, "@ERROR: setgroups failed\n");
377 rsyserr(FERROR, errno, "setuid %d failed", (int) uid);
378 io_printf(f_out, "@ERROR: setuid failed\n");
382 am_root = (getuid() == 0);
385 io_printf(f_out, "@RSYNCD: OK\n");
387 argv[argc++] = "rsyncd";
390 if (!read_line(f_in, line, sizeof(line)-1)) {
398 argv[argc] = strdup(p);
404 if (start_glob == 1) {
408 glob_expand(name, argv, &argc, MAX_ARGS);
413 if (strcmp(line,".") == 0) {
417 if (argc == MAX_ARGS) {
422 if (sanitize_paths) {
424 * Note that this is applied to all parameters, whether or not
425 * they are filenames, but no other legal parameters contain
426 * the forms that need to be sanitized so it doesn't hurt;
427 * it is not known at this point which parameters are files
430 for (i = 1; i < argc; i++) {
431 sanitize_path(argv[i], NULL);
436 ret = parse_arguments(&argc, (const char ***) &argp, 0);
438 if (filesfrom_fd == 0)
443 rprintf(FINFO,"rsync %s %s from %s@%s (%s)\n",
445 request, auth_user, host, addr);
447 rprintf(FINFO,"rsync %s %s from %s (%s)\n",
449 request, host, addr);
455 /* don't allow the logs to be flooded too fast */
456 if (verbose > 1) verbose = 1;
459 if (protocol_version < 23) {
460 if (protocol_version == 22 || (protocol_version > 17 && am_sender))
461 io_start_multiplex_out(f_out);
464 /* For later protocol versions, we don't start multiplexing
465 * until we've configured nonblocking in start_server. That
466 * means we're in a sticky situation now: there's no way to
467 * convey errors to the client. */
469 /* FIXME: Hold off on reporting option processing errors until
470 * we've set up nonblocking and multiplexed IO and can get the
471 * message back to them. */
474 exit_cleanup(RERR_UNSUPPORTED);
478 extern int io_timeout;
479 io_timeout = lp_timeout(i);
482 start_server(f_in, f_out, argc, argp);
487 /* send a list of available modules to the client. Don't list those
488 with "list = False". */
489 static void send_listing(int fd)
491 int n = lp_numservices();
496 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
498 if (protocol_version >= 25)
499 io_printf(fd,"@RSYNCD: EXIT\n");
502 /* this is called when a connection is established to a client
503 and we want to start talking. The setup of the system is done from
505 int start_daemon(int f_in, int f_out)
510 extern char *config_file;
511 extern int am_server;
513 if (!lp_load(config_file, 0)) {
514 exit_cleanup(RERR_SYNTAX);
520 set_socket_options(f_in, "SO_KEEPALIVE");
521 set_socket_options(f_in, lp_socket_options());
522 set_nonblocking(f_in);
525 io_printf(f_out, "@RSYNCD: %d\n", PROTOCOL_VERSION);
527 motd = lp_motd_file();
529 FILE *f = fopen(motd,"r");
530 while (f && !feof(f)) {
531 int len = fread(line, 1, sizeof(line)-1, f);
534 io_printf(f_out, "%s", line);
538 io_printf(f_out, "\n");
541 if (!read_line(f_in, line, sizeof(line)-1)) {
545 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
546 io_printf(f_out, "@ERROR: protocol startup error\n");
549 if (protocol_version > remote_protocol)
550 protocol_version = remote_protocol;
554 if (!read_line(f_in, line, sizeof(line)-1)) {
558 if (!*line || strcmp(line,"#list")==0) {
564 /* it's some sort of command that I don't understand */
565 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
571 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
576 return rsync_module(f_in, f_out, i);
580 int daemon_main(void)
582 extern char *config_file;
583 extern int orig_umask;
585 extern int no_detach;
587 if (is_a_socket(STDIN_FILENO)) {
590 /* we are running via inetd - close off stdout and
591 * stderr so that library functions (and getopt) don't
592 * try to use them. Redirect them to /dev/null */
595 open("/dev/null", O_RDWR);
598 return start_daemon(STDIN_FILENO, STDIN_FILENO);
604 if (!lp_load(config_file, 1)) {
605 exit_cleanup(RERR_SYNTAX);
610 rprintf(FINFO, "rsyncd version %s starting, listening on port %d\n",
611 RSYNC_VERSION, rsync_port);
612 /* TODO: If listening on a particular address, then show that
613 * address too. In fact, why not just do inet_ntop on the
614 * local address??? */
616 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
619 int pid = (int) getpid();
620 cleanup_set_pid(pid);
621 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
622 0666 & ~orig_umask)) == -1) {
624 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
625 exit_cleanup(RERR_FILEIO);
627 snprintf(pidbuf, sizeof(pidbuf), "%d\n", pid);
628 write(fd, pidbuf, strlen(pidbuf));
632 start_accept_loop(rsync_port, start_daemon);