| 1 | /* -*- c-file-style: "linux"; -*- |
| 2 | |
| 3 | Copyright (C) 1998-2000 by Andrew Tridgell |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 2 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program; if not, write to the Free Software |
| 17 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 18 | */ |
| 19 | |
| 20 | /* the socket based protocol for setting up a connection with rsyncd */ |
| 21 | |
| 22 | #include "rsync.h" |
| 23 | |
| 24 | extern int module_id; |
| 25 | extern int read_only; |
| 26 | extern int verbose; |
| 27 | extern int rsync_port; |
| 28 | char *auth_user; |
| 29 | int sanitize_paths = 0; |
| 30 | |
| 31 | |
| 32 | /* |
| 33 | * Run a client connected to an rsyncd. The alternative to this |
| 34 | * function for remote-shell connections is do_cmd. |
| 35 | */ |
| 36 | int start_socket_client(char *host, char *path, int argc, char *argv[]) |
| 37 | { |
| 38 | int fd, i; |
| 39 | char *sargs[MAX_ARGS]; |
| 40 | int sargc=0; |
| 41 | char line[MAXPATHLEN]; |
| 42 | char *p, *user=NULL; |
| 43 | extern int remote_version; |
| 44 | extern int am_sender; |
| 45 | extern struct in_addr socket_address; |
| 46 | extern char *shell_cmd; |
| 47 | |
| 48 | if (argc == 0 && !am_sender) { |
| 49 | extern int list_only; |
| 50 | list_only = 1; |
| 51 | } |
| 52 | |
| 53 | /* This is just a friendliness enhancement: if the connection |
| 54 | * is to an rsyncd then there is no point specifying the -e option. |
| 55 | * Note that this is only set if the -e was explicitly specified, |
| 56 | * not if the environment variable just happens to be set. |
| 57 | * See http://lists.samba.org/pipermail/rsync/2000-September/002744.html |
| 58 | */ |
| 59 | if (shell_cmd) { |
| 60 | rprintf(FERROR, "WARNING: --rsh or -e option ignored when " |
| 61 | "connecting to rsync daemon\n"); |
| 62 | /* continue */ |
| 63 | } |
| 64 | |
| 65 | if (*path == '/') { |
| 66 | rprintf(FERROR,"ERROR: The remote path must start with a module name\n"); |
| 67 | return -1; |
| 68 | } |
| 69 | |
| 70 | p = strchr(host, '@'); |
| 71 | if (p) { |
| 72 | user = host; |
| 73 | host = p+1; |
| 74 | *p = 0; |
| 75 | } |
| 76 | |
| 77 | if (!user) user = getenv("USER"); |
| 78 | if (!user) user = getenv("LOGNAME"); |
| 79 | |
| 80 | fd = open_socket_out(host, rsync_port, &socket_address); |
| 81 | if (fd == -1) { |
| 82 | exit_cleanup(RERR_SOCKETIO); |
| 83 | } |
| 84 | |
| 85 | server_options(sargs,&sargc); |
| 86 | |
| 87 | sargs[sargc++] = "."; |
| 88 | |
| 89 | if (path && *path) |
| 90 | sargs[sargc++] = path; |
| 91 | |
| 92 | sargs[sargc] = NULL; |
| 93 | |
| 94 | io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION); |
| 95 | |
| 96 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 97 | return -1; |
| 98 | } |
| 99 | |
| 100 | if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) { |
| 101 | return -1; |
| 102 | } |
| 103 | |
| 104 | p = strchr(path,'/'); |
| 105 | if (p) *p = 0; |
| 106 | io_printf(fd,"%s\n",path); |
| 107 | if (p) *p = '/'; |
| 108 | |
| 109 | while (1) { |
| 110 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 111 | return -1; |
| 112 | } |
| 113 | |
| 114 | if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) { |
| 115 | auth_client(fd, user, line+18); |
| 116 | continue; |
| 117 | } |
| 118 | |
| 119 | if (strcmp(line,"@RSYNCD: OK") == 0) break; |
| 120 | rprintf(FINFO,"%s\n", line); |
| 121 | } |
| 122 | |
| 123 | for (i=0;i<sargc;i++) { |
| 124 | io_printf(fd,"%s\n", sargs[i]); |
| 125 | } |
| 126 | io_printf(fd,"\n"); |
| 127 | |
| 128 | if (remote_version < 23) { |
| 129 | if (remote_version == 22 || (remote_version > 17 && !am_sender)) |
| 130 | io_start_multiplex_in(fd); |
| 131 | } |
| 132 | |
| 133 | return client_run(fd, fd, -1, argc, argv); |
| 134 | } |
| 135 | |
| 136 | |
| 137 | |
| 138 | static int rsync_module(int fd, int i) |
| 139 | { |
| 140 | int argc=0; |
| 141 | char *argv[MAX_ARGS]; |
| 142 | char **argp; |
| 143 | char line[MAXPATHLEN]; |
| 144 | uid_t uid = (uid_t)-2; |
| 145 | gid_t gid = (gid_t)-2; |
| 146 | char *p; |
| 147 | char *addr = client_addr(fd); |
| 148 | char *host = client_name(fd); |
| 149 | char *name = lp_name(i); |
| 150 | int use_chroot = lp_use_chroot(i); |
| 151 | int start_glob=0; |
| 152 | int ret; |
| 153 | char *request=NULL; |
| 154 | extern int am_sender; |
| 155 | extern int remote_version; |
| 156 | extern int am_root; |
| 157 | |
| 158 | if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) { |
| 159 | rprintf(FERROR,"rsync denied on module %s from %s (%s)\n", |
| 160 | name, client_name(fd), client_addr(fd)); |
| 161 | io_printf(fd,"@ERROR: access denied to %s from %s (%s)\n", |
| 162 | name, client_name(fd), client_addr(fd)); |
| 163 | return -1; |
| 164 | } |
| 165 | |
| 166 | if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) { |
| 167 | if (errno) { |
| 168 | rprintf(FERROR,"failed to open lock file %s : %s\n", |
| 169 | lp_lock_file(i), strerror(errno)); |
| 170 | io_printf(fd,"@ERROR: failed to open lock file %s : %s\n", |
| 171 | lp_lock_file(i), strerror(errno)); |
| 172 | } else { |
| 173 | rprintf(FERROR,"max connections (%d) reached\n", |
| 174 | lp_max_connections(i)); |
| 175 | io_printf(fd,"@ERROR: max connections (%d) reached - try again later\n", lp_max_connections(i)); |
| 176 | } |
| 177 | return -1; |
| 178 | } |
| 179 | |
| 180 | |
| 181 | auth_user = auth_server(fd, i, addr, "@RSYNCD: AUTHREQD "); |
| 182 | |
| 183 | if (!auth_user) { |
| 184 | rprintf(FERROR,"auth failed on module %s from %s (%s)\n", |
| 185 | name, client_name(fd), client_addr(fd)); |
| 186 | io_printf(fd,"@ERROR: auth failed on module %s\n",name); |
| 187 | return -1; |
| 188 | } |
| 189 | |
| 190 | module_id = i; |
| 191 | |
| 192 | am_root = (getuid() == 0); |
| 193 | |
| 194 | if (am_root) { |
| 195 | p = lp_uid(i); |
| 196 | if (!name_to_uid(p, &uid)) { |
| 197 | if (!isdigit(*p)) { |
| 198 | rprintf(FERROR,"Invalid uid %s\n", p); |
| 199 | io_printf(fd,"@ERROR: invalid uid\n"); |
| 200 | return -1; |
| 201 | } |
| 202 | uid = atoi(p); |
| 203 | } |
| 204 | |
| 205 | p = lp_gid(i); |
| 206 | if (!name_to_gid(p, &gid)) { |
| 207 | if (!isdigit(*p)) { |
| 208 | rprintf(FERROR,"Invalid gid %s\n", p); |
| 209 | io_printf(fd,"@ERROR: invalid gid\n"); |
| 210 | return -1; |
| 211 | } |
| 212 | gid = atoi(p); |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | p = lp_include_from(i); |
| 217 | add_exclude_file(p, 1, 1); |
| 218 | |
| 219 | p = lp_include(i); |
| 220 | add_include_line(p); |
| 221 | |
| 222 | p = lp_exclude_from(i); |
| 223 | add_exclude_file(p, 1, 0); |
| 224 | |
| 225 | p = lp_exclude(i); |
| 226 | add_exclude_line(p); |
| 227 | |
| 228 | log_init(); |
| 229 | |
| 230 | if (use_chroot) { |
| 231 | if (chroot(lp_path(i))) { |
| 232 | rsyserr(FERROR, errno, "chroot %s failed", lp_path(i)); |
| 233 | io_printf(fd,"@ERROR: chroot failed\n"); |
| 234 | return -1; |
| 235 | } |
| 236 | |
| 237 | if (!push_dir("/", 0)) { |
| 238 | rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i)); |
| 239 | io_printf(fd,"@ERROR: chdir failed\n"); |
| 240 | return -1; |
| 241 | } |
| 242 | |
| 243 | } else { |
| 244 | if (!push_dir(lp_path(i), 0)) { |
| 245 | rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i)); |
| 246 | io_printf(fd,"@ERROR: chdir failed\n"); |
| 247 | return -1; |
| 248 | } |
| 249 | sanitize_paths = 1; |
| 250 | } |
| 251 | |
| 252 | if (am_root) { |
| 253 | if (setgid(gid)) { |
| 254 | rsyserr(FERROR, errno, "setgid %d failed", gid); |
| 255 | io_printf(fd,"@ERROR: setgid failed\n"); |
| 256 | return -1; |
| 257 | } |
| 258 | |
| 259 | if (setuid(uid)) { |
| 260 | rsyserr(FERROR, errno, "setuid %d failed", uid); |
| 261 | io_printf(fd,"@ERROR: setuid failed\n"); |
| 262 | return -1; |
| 263 | } |
| 264 | |
| 265 | am_root = (getuid() == 0); |
| 266 | } |
| 267 | |
| 268 | io_printf(fd,"@RSYNCD: OK\n"); |
| 269 | |
| 270 | argv[argc++] = "rsyncd"; |
| 271 | |
| 272 | while (1) { |
| 273 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 274 | return -1; |
| 275 | } |
| 276 | |
| 277 | if (!*line) break; |
| 278 | |
| 279 | p = line; |
| 280 | |
| 281 | argv[argc] = strdup(p); |
| 282 | if (!argv[argc]) { |
| 283 | return -1; |
| 284 | } |
| 285 | |
| 286 | if (start_glob) { |
| 287 | if (start_glob == 1) { |
| 288 | request = strdup(p); |
| 289 | start_glob++; |
| 290 | } |
| 291 | glob_expand(name, argv, &argc, MAX_ARGS); |
| 292 | } else { |
| 293 | argc++; |
| 294 | } |
| 295 | |
| 296 | if (strcmp(line,".") == 0) { |
| 297 | start_glob = 1; |
| 298 | } |
| 299 | |
| 300 | if (argc == MAX_ARGS) { |
| 301 | return -1; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | if (sanitize_paths) { |
| 306 | /* |
| 307 | * Note that this is applied to all parameters, whether or not |
| 308 | * they are filenames, but no other legal parameters contain |
| 309 | * the forms that need to be sanitized so it doesn't hurt; |
| 310 | * it is not known at this point which parameters are files |
| 311 | * and which aren't. |
| 312 | */ |
| 313 | for (i = 1; i < argc; i++) { |
| 314 | sanitize_path(argv[i], NULL); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | ret = parse_arguments(argc, argv, 0); |
| 319 | |
| 320 | if (request) { |
| 321 | if (*auth_user) { |
| 322 | rprintf(FINFO,"rsync %s %s from %s@%s (%s)\n", |
| 323 | am_sender?"on":"to", |
| 324 | request, auth_user, host, addr); |
| 325 | } else { |
| 326 | rprintf(FINFO,"rsync %s %s from %s (%s)\n", |
| 327 | am_sender?"on":"to", |
| 328 | request, host, addr); |
| 329 | } |
| 330 | free(request); |
| 331 | } |
| 332 | |
| 333 | #if !TRIDGE |
| 334 | /* don't allow the logs to be flooded too fast */ |
| 335 | if (verbose > 1) verbose = 1; |
| 336 | #endif |
| 337 | |
| 338 | argc -= optind; |
| 339 | argp = argv + optind; |
| 340 | optind = 0; |
| 341 | |
| 342 | if (remote_version < 23) { |
| 343 | if (remote_version == 22 || (remote_version > 17 && am_sender)) |
| 344 | io_start_multiplex_out(fd); |
| 345 | } |
| 346 | |
| 347 | if (!ret) { |
| 348 | option_error(); |
| 349 | } |
| 350 | |
| 351 | if (lp_timeout(i)) { |
| 352 | extern int io_timeout; |
| 353 | io_timeout = lp_timeout(i); |
| 354 | } |
| 355 | |
| 356 | start_server(fd, fd, argc, argp); |
| 357 | |
| 358 | return 0; |
| 359 | } |
| 360 | |
| 361 | /* send a list of available modules to the client. Don't list those |
| 362 | with "list = False". */ |
| 363 | static void send_listing(int fd) |
| 364 | { |
| 365 | int n = lp_numservices(); |
| 366 | int i; |
| 367 | |
| 368 | for (i=0;i<n;i++) |
| 369 | if (lp_list(i)) |
| 370 | io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i)); |
| 371 | } |
| 372 | |
| 373 | /* this is called when a socket connection is established to a client |
| 374 | and we want to start talking. The setup of the system is done from |
| 375 | here */ |
| 376 | static int start_daemon(int fd) |
| 377 | { |
| 378 | char line[200]; |
| 379 | char *motd; |
| 380 | int i = -1; |
| 381 | extern char *config_file; |
| 382 | extern int remote_version; |
| 383 | |
| 384 | if (!lp_load(config_file, 0)) { |
| 385 | exit_cleanup(RERR_SYNTAX); |
| 386 | } |
| 387 | |
| 388 | set_socket_options(fd,"SO_KEEPALIVE"); |
| 389 | set_socket_options(fd,lp_socket_options()); |
| 390 | set_nonblocking(fd); |
| 391 | |
| 392 | io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION); |
| 393 | |
| 394 | motd = lp_motd_file(); |
| 395 | if (motd && *motd) { |
| 396 | FILE *f = fopen(motd,"r"); |
| 397 | while (f && !feof(f)) { |
| 398 | int len = fread(line, 1, sizeof(line)-1, f); |
| 399 | if (len > 0) { |
| 400 | line[len] = 0; |
| 401 | io_printf(fd,"%s", line); |
| 402 | } |
| 403 | } |
| 404 | if (f) fclose(f); |
| 405 | io_printf(fd,"\n"); |
| 406 | } |
| 407 | |
| 408 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 409 | return -1; |
| 410 | } |
| 411 | |
| 412 | if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) { |
| 413 | io_printf(fd,"@ERROR: protocol startup error\n"); |
| 414 | return -1; |
| 415 | } |
| 416 | |
| 417 | while (i == -1) { |
| 418 | line[0] = 0; |
| 419 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 420 | return -1; |
| 421 | } |
| 422 | |
| 423 | if (!*line || strcmp(line,"#list")==0) { |
| 424 | send_listing(fd); |
| 425 | return -1; |
| 426 | } |
| 427 | |
| 428 | if (*line == '#') { |
| 429 | /* it's some sort of command that I don't understand */ |
| 430 | io_printf(fd,"@ERROR: Unknown command '%s'\n", line); |
| 431 | return -1; |
| 432 | } |
| 433 | |
| 434 | i = lp_number(line); |
| 435 | if (i == -1) { |
| 436 | io_printf(fd,"@ERROR: Unknown module '%s'\n", line); |
| 437 | return -1; |
| 438 | } |
| 439 | } |
| 440 | |
| 441 | return rsync_module(fd, i); |
| 442 | } |
| 443 | |
| 444 | |
| 445 | int daemon_main(void) |
| 446 | { |
| 447 | extern char *config_file; |
| 448 | extern int orig_umask; |
| 449 | char *pid_file; |
| 450 | |
| 451 | if (is_a_socket(STDIN_FILENO)) { |
| 452 | int i; |
| 453 | |
| 454 | /* we are running via inetd - close off stdout and |
| 455 | stderr so that library functions (and getopt) don't |
| 456 | try to use them. Redirect them to /dev/null */ |
| 457 | for (i=1;i<3;i++) { |
| 458 | close(i); |
| 459 | open("/dev/null", O_RDWR); |
| 460 | } |
| 461 | |
| 462 | return start_daemon(STDIN_FILENO); |
| 463 | } |
| 464 | |
| 465 | become_daemon(); |
| 466 | |
| 467 | if (!lp_load(config_file, 1)) { |
| 468 | exit_cleanup(RERR_SYNTAX); |
| 469 | } |
| 470 | |
| 471 | log_init(); |
| 472 | |
| 473 | rprintf(FINFO,"rsyncd version %s starting\n",VERSION); |
| 474 | |
| 475 | if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) { |
| 476 | char pidbuf[16]; |
| 477 | int fd; |
| 478 | int pid = (int) getpid(); |
| 479 | cleanup_set_pid(pid); |
| 480 | if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC, |
| 481 | 0666 & ~orig_umask)) == -1) { |
| 482 | cleanup_set_pid(0); |
| 483 | rsyserr(FLOG, errno, "failed to create pid file %s", pid_file); |
| 484 | exit_cleanup(RERR_FILEIO); |
| 485 | } |
| 486 | slprintf(pidbuf, sizeof(pidbuf), "%d\n", pid); |
| 487 | write(fd, pidbuf, strlen(pidbuf)); |
| 488 | close(fd); |
| 489 | } |
| 490 | |
| 491 | start_accept_loop(rsync_port, start_daemon); |
| 492 | return -1; |
| 493 | } |
| 494 | |