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 kludge_around_eof;
38 extern int daemon_over_rsh;
40 extern int sanitize_paths;
41 extern int filesfrom_fd;
42 extern int remote_protocol;
43 extern int protocol_version;
44 extern int io_timeout;
45 extern int select_timeout;
46 extern int orig_umask;
48 extern int default_af_hint;
49 extern char *bind_address;
50 extern struct filter_list_struct server_filter_list;
51 extern char *config_file;
52 extern char *files_from;
57 /* Length of lp_path() string when in daemon mode & not chrooted, else 0. */
58 unsigned int module_dirlen = 0;
61 * Run a client connected to an rsyncd. The alternative to this
62 * function for remote-shell connections is do_cmd().
64 * After negotiating which module to use and reading the server's
65 * motd, this hands over to client_run(). Telling the server the
66 * module will cause it to chroot/setuid/etc.
68 * Instead of doing a transfer, the client may at this stage instead
69 * get a listing of remote modules and exit.
71 * @return -1 for error in startup, or the result of client_run().
72 * Either way, it eventually gets passed to exit_cleanup().
74 int start_socket_client(char *host, char *path, int argc, char *argv[])
77 char *p, *user = NULL;
79 /* This is redundant with code in start_inband_exchange(), but this
80 * short-circuits a problem in the client before we open a socket,
81 * and the extra check won't hurt. */
84 "ERROR: The remote path must start with a module name not a /\n");
88 if ((p = strchr(host, '@')) != NULL) {
95 rsync_port = RSYNC_PORT;
97 fd = open_socket_out_wrapped(host, rsync_port, bind_address,
100 exit_cleanup(RERR_SOCKETIO);
102 ret = start_inband_exchange(user, path, fd, fd, argc);
104 return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
107 int start_inband_exchange(char *user, char *path, int f_in, int f_out,
111 char *sargs[MAX_ARGS];
113 char line[MAXPATHLEN];
116 if (argc == 0 && !am_sender)
121 "ERROR: The remote path must start with a module name\n");
126 user = getenv("USER");
128 user = getenv("LOGNAME");
130 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
132 if (!read_line(f_in, line, sizeof line - 1)) {
133 rprintf(FERROR, "rsync: did not see server greeting\n");
137 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
138 /* note that read_line strips of \n or \r */
139 rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
143 if (protocol_version > remote_protocol)
144 protocol_version = remote_protocol;
146 if (list_only && protocol_version >= 29)
149 /* set daemon_over_rsh to false since we need to build the
150 * true set of args passed through the rsh/ssh connection;
151 * this is a no-op for direct-socket-connection mode */
153 server_options(sargs, &sargc);
155 sargs[sargc++] = ".";
158 sargs[sargc++] = path;
163 print_child_argv(sargs);
165 p = strchr(path,'/');
167 io_printf(f_out, "%s\n", path);
170 /* Old servers may just drop the connection here,
171 rather than sending a proper EXIT command. Yuck. */
172 kludge_around_eof = list_only && (protocol_version < 25);
175 if (!read_line(f_in, line, sizeof line - 1)) {
176 rprintf(FERROR, "rsync: didn't get server startup line\n");
180 if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
181 auth_client(f_out, user, line+18);
185 if (strcmp(line,"@RSYNCD: OK") == 0)
188 if (strcmp(line,"@RSYNCD: EXIT") == 0) {
189 /* This is sent by recent versions of the
190 * server to terminate the listing of modules.
191 * We don't want to go on and transfer
192 * anything; just exit. */
196 if (strncmp(line, "@ERROR", 6) == 0) {
197 rprintf(FERROR, "%s\n", line);
198 /* This is always fatal; the server will now
199 * close the socket. */
200 return RERR_STARTCLIENT;
202 rprintf(FINFO,"%s\n", line);
205 kludge_around_eof = False;
207 for (i = 0; i < sargc; i++) {
208 io_printf(f_out, "%s\n", sargs[i]);
210 io_printf(f_out, "\n");
212 if (protocol_version < 23) {
213 if (protocol_version == 22 || !am_sender)
214 io_start_multiplex_in();
222 static int rsync_module(int f_in, int f_out, int i)
228 char line[MAXPATHLEN];
229 uid_t uid = (uid_t)-2; /* canonically "nobody" */
230 gid_t gid = (gid_t)-2;
232 char *addr = client_addr(f_in);
233 char *host = client_name(f_in);
234 char *name = lp_name(i);
235 int use_chroot = lp_use_chroot(i);
238 char *request = NULL;
240 if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
241 rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
244 io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
247 "@ERROR: access denied to %s from %s (%s)\n",
253 if (am_daemon && am_server) {
254 rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
258 if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
260 rsyserr(FLOG, errno, "failed to open lock file %s",
262 io_printf(f_out, "@ERROR: failed to open lock file %s\n",
265 rprintf(FLOG, "max connections (%d) reached\n",
266 lp_max_connections(i));
267 io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n",
268 lp_max_connections(i));
273 auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD ");
276 rprintf(FLOG, "auth failed on module %s from %s (%s)\n",
278 io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
284 if (lp_read_only(module_id))
287 am_root = (MY_UID() == 0);
291 if (!name_to_uid(p, &uid)) {
292 if (!isdigit(*(unsigned char *)p)) {
293 rprintf(FLOG, "Invalid uid %s\n", p);
294 io_printf(f_out, "@ERROR: invalid uid %s\n", p);
301 if (!name_to_gid(p, &gid)) {
302 if (!isdigit(*(unsigned char *)p)) {
303 rprintf(FLOG, "Invalid gid %s\n", p);
304 io_printf(f_out, "@ERROR: invalid gid %s\n", p);
311 /* TODO: If we're not root, but the configuration requests
312 * that we change to some uid other than the current one, then
315 /* TODO: Perhaps take a list of gids, and make them into the
316 * supplementary groups. */
320 set_filter_dir("/", 1);
322 module_dirlen = strlen(lp_path(i));
323 set_filter_dir(lp_path(i), module_dirlen);
327 add_filter(&server_filter_list, p,
328 XFLG_WORD_SPLIT | XFLG_ABS_PATH);
330 p = lp_include_from(i);
331 add_filter_file(&server_filter_list, p,
332 XFLG_FATAL_ERRORS | XFLG_ABS_PATH | XFLG_DEF_INCLUDE);
335 add_filter(&server_filter_list, p,
336 XFLG_WORD_SPLIT | XFLG_ABS_PATH | XFLG_DEF_INCLUDE);
338 p = lp_exclude_from(i);
339 add_filter_file(&server_filter_list, p,
340 XFLG_FATAL_ERRORS | XFLG_ABS_PATH | XFLG_DEF_EXCLUDE);
343 add_filter(&server_filter_list, p,
344 XFLG_WORD_SPLIT | XFLG_ABS_PATH | XFLG_DEF_EXCLUDE);
350 * XXX: The 'use chroot' flag is a fairly reliable
351 * source of confusion, because it fails under two
352 * important circumstances: running as non-root,
353 * running on Win32 (or possibly others). On the
354 * other hand, if you are running as root, then it
355 * might be better to always use chroot.
357 * So, perhaps if we can't chroot we should just issue
358 * a warning, unless a "require chroot" flag is set,
359 * in which case we fail.
361 if (chroot(lp_path(i))) {
362 rsyserr(FLOG, errno, "chroot %s failed", lp_path(i));
363 io_printf(f_out, "@ERROR: chroot failed\n");
367 if (!push_dir("/")) {
368 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
369 io_printf(f_out, "@ERROR: chdir failed\n");
374 if (!push_dir(lp_path(i))) {
375 rsyserr(FLOG, errno, "chdir %s failed\n", lp_path(i));
376 io_printf(f_out, "@ERROR: chdir failed\n");
383 /* XXXX: You could argue that if the daemon is started
384 * by a non-root user and they explicitly specify a
385 * gid, then we should try to change to that gid --
386 * this could be possible if it's already in their
387 * supplementary groups. */
389 /* TODO: Perhaps we need to document that if rsyncd is
390 * started by somebody other than root it will inherit
391 * all their supplementary groups. */
394 rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
395 io_printf(f_out, "@ERROR: setgid failed\n");
398 #ifdef HAVE_SETGROUPS
399 /* Get rid of any supplementary groups this process
400 * might have inheristed. */
401 if (setgroups(1, &gid)) {
402 rsyserr(FLOG, errno, "setgroups failed");
403 io_printf(f_out, "@ERROR: setgroups failed\n");
409 rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
410 io_printf(f_out, "@ERROR: setuid failed\n");
414 am_root = (MY_UID() == 0);
417 io_printf(f_out, "@RSYNCD: OK\n");
420 if (!(argv = new_array(char *, maxargs)))
421 out_of_memory("rsync_module");
422 argv[argc++] = "rsyncd";
425 if (!read_line(f_in, line, sizeof line - 1))
433 if (argc == maxargs) {
435 if (!(argv = realloc_array(argv, char *, maxargs)))
436 out_of_memory("rsync_module");
438 if (!(argv[argc] = strdup(p)))
439 out_of_memory("rsync_module");
442 if (start_glob == 1) {
446 glob_expand(name, &argv, &argc, &maxargs);
450 if (strcmp(line, ".") == 0)
454 verbose = 0; /* future verbosity is controlled by client options */
456 ret = parse_arguments(&argc, (const char ***) &argp, 0);
458 if (filesfrom_fd == 0)
463 rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
464 am_sender ? "on" : "to",
465 request, auth_user, host, addr);
467 rprintf(FLOG, "rsync %s %s from %s (%s)\n",
468 am_sender ? "on" : "to",
469 request, host, addr);
475 /* don't allow the logs to be flooded too fast */
476 if (verbose > lp_max_verbosity())
477 verbose = lp_max_verbosity();
480 if (protocol_version < 23
481 && (protocol_version == 22 || am_sender))
482 io_start_multiplex_out();
484 /* We have to get I/O multiplexing started so that we can
485 * get the error back to the client. This means getting
486 * the protocol setup finished first in later versions. */
487 setup_protocol(f_out, f_in);
488 if (files_from && !am_sender && strcmp(files_from, "-") != 0)
489 write_byte(f_out, 0);
490 io_start_multiplex_out();
496 exit_cleanup(RERR_UNSUPPORTED);
500 io_timeout = lp_timeout(i);
501 if (io_timeout < select_timeout)
502 select_timeout = io_timeout;
505 start_server(f_in, f_out, argc, argp);
510 /* send a list of available modules to the client. Don't list those
511 with "list = False". */
512 static void send_listing(int fd)
514 int n = lp_numservices();
517 for (i = 0; i < n; i++) {
519 io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
522 if (protocol_version >= 25)
523 io_printf(fd,"@RSYNCD: EXIT\n");
526 /* this is called when a connection is established to a client
527 and we want to start talking. The setup of the system is done from
529 int start_daemon(int f_in, int f_out)
535 io_set_sock_fds(f_in, f_out);
537 if (!lp_load(config_file, 0))
538 exit_cleanup(RERR_SYNTAX);
543 set_socket_options(f_in, "SO_KEEPALIVE");
544 set_socket_options(f_in, lp_socket_options());
545 set_nonblocking(f_in);
548 io_printf(f_out, "@RSYNCD: %d\n", protocol_version);
550 motd = lp_motd_file();
552 FILE *f = fopen(motd,"r");
553 while (f && !feof(f)) {
554 int len = fread(line, 1, sizeof line - 1, f);
557 io_printf(f_out, "%s", line);
562 io_printf(f_out, "\n");
565 if (!read_line(f_in, line, sizeof line - 1))
568 if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) {
569 io_printf(f_out, "@ERROR: protocol startup error\n");
572 if (protocol_version > remote_protocol)
573 protocol_version = remote_protocol;
576 if (!read_line(f_in, line, sizeof line - 1))
579 if (!*line || strcmp(line, "#list") == 0) {
585 /* it's some sort of command that I don't understand */
586 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
590 if ((i = lp_number(line)) < 0) {
591 char *addr = client_addr(f_in);
592 char *host = client_name(f_in);
593 rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
595 io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
599 return rsync_module(f_in, f_out, i);
603 int daemon_main(void)
607 if (is_a_socket(STDIN_FILENO)) {
610 /* we are running via inetd - close off stdout and
611 * stderr so that library functions (and getopt) don't
612 * try to use them. Redirect them to /dev/null */
613 for (i = 1; i < 3; i++) {
615 open("/dev/null", O_RDWR);
618 return start_daemon(STDIN_FILENO, STDIN_FILENO);
624 if (!lp_load(config_file, 1))
625 exit_cleanup(RERR_SYNTAX);
627 if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
628 rsync_port = RSYNC_PORT;
629 if (bind_address == NULL && *lp_bind_address())
630 bind_address = lp_bind_address();
634 rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
635 RSYNC_VERSION, rsync_port);
636 /* TODO: If listening on a particular address, then show that
637 * address too. In fact, why not just do inet_ntop on the
638 * local address??? */
640 if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
643 pid_t pid = getpid();
644 cleanup_set_pid(pid);
645 if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC,
646 0666 & ~orig_umask)) == -1) {
648 rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
649 exit_cleanup(RERR_FILEIO);
651 snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
652 write(fd, pidbuf, strlen(pidbuf));
656 start_accept_loop(rsync_port, start_daemon);