| 1 | /* |
| 2 | * The socket based protocol for setting up a connection with rsyncd. |
| 3 | * |
| 4 | * Copyright (C) 1998-2001 Andrew Tridgell <tridge@samba.org> |
| 5 | * Copyright (C) 2001-2002 Martin Pool <mbp@samba.org> |
| 6 | * Copyright (C) 2002-2007 Wayne Davison |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; either version 3 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License along |
| 19 | * with this program; if not, visit the http://fsf.org website. |
| 20 | */ |
| 21 | |
| 22 | #include "rsync.h" |
| 23 | |
| 24 | extern int verbose; |
| 25 | extern int quiet; |
| 26 | extern int output_motd; |
| 27 | extern int list_only; |
| 28 | extern int am_sender; |
| 29 | extern int am_server; |
| 30 | extern int am_daemon; |
| 31 | extern int am_root; |
| 32 | extern int rsync_port; |
| 33 | extern int ignore_errors; |
| 34 | extern int kluge_around_eof; |
| 35 | extern int daemon_over_rsh; |
| 36 | extern int sanitize_paths; |
| 37 | extern int filesfrom_fd; |
| 38 | extern int remote_protocol; |
| 39 | extern int protocol_version; |
| 40 | extern int io_timeout; |
| 41 | extern int no_detach; |
| 42 | extern int default_af_hint; |
| 43 | extern int logfile_format_has_i; |
| 44 | extern int logfile_format_has_o_or_i; |
| 45 | extern mode_t orig_umask; |
| 46 | extern char *bind_address; |
| 47 | extern char *sockopts; |
| 48 | extern char *config_file; |
| 49 | extern char *logfile_format; |
| 50 | extern char *files_from; |
| 51 | extern char *tmpdir; |
| 52 | extern struct chmod_mode_struct *chmod_modes; |
| 53 | extern struct filter_list_struct server_filter_list; |
| 54 | extern char curr_dir[]; |
| 55 | |
| 56 | char *auth_user; |
| 57 | int read_only = 0; |
| 58 | int module_id = -1; |
| 59 | struct chmod_mode_struct *daemon_chmod_modes; |
| 60 | |
| 61 | /* module_dirlen is the length of the module_dir string when in daemon |
| 62 | * mode, not chrooted, and the path is not "/"; otherwise 0. */ |
| 63 | char *module_dir = NULL; |
| 64 | unsigned int module_dirlen = 0; |
| 65 | |
| 66 | static int rl_nulls = 0; |
| 67 | |
| 68 | #ifdef HAVE_SIGACTION |
| 69 | static struct sigaction sigact; |
| 70 | #endif |
| 71 | |
| 72 | /** |
| 73 | * Run a client connected to an rsyncd. The alternative to this |
| 74 | * function for remote-shell connections is do_cmd(). |
| 75 | * |
| 76 | * After negotiating which module to use and reading the server's |
| 77 | * motd, this hands over to client_run(). Telling the server the |
| 78 | * module will cause it to chroot/setuid/etc. |
| 79 | * |
| 80 | * Instead of doing a transfer, the client may at this stage instead |
| 81 | * get a listing of remote modules and exit. |
| 82 | * |
| 83 | * @return -1 for error in startup, or the result of client_run(). |
| 84 | * Either way, it eventually gets passed to exit_cleanup(). |
| 85 | **/ |
| 86 | int start_socket_client(char *host, int remote_argc, char *remote_argv[], |
| 87 | int argc, char *argv[]) |
| 88 | { |
| 89 | int fd, ret; |
| 90 | char *p, *user = NULL; |
| 91 | |
| 92 | /* This is redundant with code in start_inband_exchange(), but this |
| 93 | * short-circuits a problem in the client before we open a socket, |
| 94 | * and the extra check won't hurt. */ |
| 95 | if (**remote_argv == '/') { |
| 96 | rprintf(FERROR, |
| 97 | "ERROR: The remote path must start with a module name not a /\n"); |
| 98 | return -1; |
| 99 | } |
| 100 | |
| 101 | if ((p = strrchr(host, '@')) != NULL) { |
| 102 | user = host; |
| 103 | host = p+1; |
| 104 | *p = '\0'; |
| 105 | } |
| 106 | |
| 107 | fd = open_socket_out_wrapped(host, rsync_port, bind_address, |
| 108 | default_af_hint); |
| 109 | if (fd == -1) |
| 110 | exit_cleanup(RERR_SOCKETIO); |
| 111 | |
| 112 | set_socket_options(fd, sockopts); |
| 113 | |
| 114 | ret = start_inband_exchange(fd, fd, user, remote_argc, remote_argv); |
| 115 | |
| 116 | return ret ? ret : client_run(fd, fd, -1, argc, argv); |
| 117 | } |
| 118 | |
| 119 | static int exchange_protocols(int f_in, int f_out, char *buf, size_t bufsiz, int am_client) |
| 120 | { |
| 121 | int remote_sub = -1; |
| 122 | #if SUBPROTOCOL_VERSION != 0 |
| 123 | int our_sub = protocol_version < PROTOCOL_VERSION ? 0 : SUBPROTOCOL_VERSION; |
| 124 | #else |
| 125 | int our_sub = 0; |
| 126 | #endif |
| 127 | char *motd; |
| 128 | |
| 129 | io_printf(f_out, "@RSYNCD: %d.%d\n", protocol_version, our_sub); |
| 130 | |
| 131 | if (!am_client) { |
| 132 | motd = lp_motd_file(); |
| 133 | if (motd && *motd) { |
| 134 | FILE *f = fopen(motd,"r"); |
| 135 | while (f && !feof(f)) { |
| 136 | int len = fread(buf, 1, bufsiz - 1, f); |
| 137 | if (len > 0) |
| 138 | write_buf(f_out, buf, len); |
| 139 | } |
| 140 | if (f) |
| 141 | fclose(f); |
| 142 | write_sbuf(f_out, "\n"); |
| 143 | } |
| 144 | } |
| 145 | |
| 146 | /* This strips the \n. */ |
| 147 | if (!read_line_old(f_in, buf, bufsiz)) { |
| 148 | if (am_client) |
| 149 | rprintf(FERROR, "rsync: did not see server greeting\n"); |
| 150 | return -1; |
| 151 | } |
| 152 | |
| 153 | if (sscanf(buf, "@RSYNCD: %d.%d", &remote_protocol, &remote_sub) < 1) { |
| 154 | if (am_client) |
| 155 | rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", buf); |
| 156 | else |
| 157 | io_printf(f_out, "@ERROR: protocol startup error\n"); |
| 158 | return -1; |
| 159 | } |
| 160 | |
| 161 | if (remote_sub < 0) { |
| 162 | if (remote_protocol == 30) { |
| 163 | if (am_client) |
| 164 | rprintf(FERROR, "rsync: server is speaking an incompatible beta of protocol 30\n"); |
| 165 | else |
| 166 | io_printf(f_out, "@ERROR: your client is speaking an incompatible beta of protocol 30\n"); |
| 167 | return -1; |
| 168 | } |
| 169 | remote_sub = 0; |
| 170 | } |
| 171 | |
| 172 | if (protocol_version > remote_protocol) { |
| 173 | protocol_version = remote_protocol; |
| 174 | if (remote_sub) |
| 175 | protocol_version--; |
| 176 | } else if (protocol_version == remote_protocol) { |
| 177 | if (remote_sub != our_sub) |
| 178 | protocol_version--; |
| 179 | } |
| 180 | #if SUBPROTOCOL_VERSION != 0 |
| 181 | else if (protocol_version < remote_protocol) { |
| 182 | if (our_sub) |
| 183 | protocol_version--; |
| 184 | } |
| 185 | #endif |
| 186 | |
| 187 | if (protocol_version >= 30) |
| 188 | rl_nulls = 1; |
| 189 | |
| 190 | return 0; |
| 191 | } |
| 192 | |
| 193 | int start_inband_exchange(int f_in, int f_out, const char *user, int argc, char *argv[]) |
| 194 | { |
| 195 | int i; |
| 196 | char line[BIGPATHBUFLEN]; |
| 197 | char *sargs[MAX_ARGS]; |
| 198 | int sargc = 0; |
| 199 | char *p, *path = *argv; |
| 200 | |
| 201 | if (argc == 0 && !am_sender) |
| 202 | list_only |= 1; |
| 203 | |
| 204 | if (*path == '/') { |
| 205 | rprintf(FERROR, |
| 206 | "ERROR: The remote path must start with a module name\n"); |
| 207 | return -1; |
| 208 | } |
| 209 | |
| 210 | if (!user) |
| 211 | user = getenv("USER"); |
| 212 | if (!user) |
| 213 | user = getenv("LOGNAME"); |
| 214 | |
| 215 | if (exchange_protocols(f_in, f_out, line, sizeof line, 1) < 0) |
| 216 | return -1; |
| 217 | |
| 218 | if (list_only && protocol_version >= 29) |
| 219 | list_only |= 2; |
| 220 | |
| 221 | /* set daemon_over_rsh to false since we need to build the |
| 222 | * true set of args passed through the rsh/ssh connection; |
| 223 | * this is a no-op for direct-socket-connection mode */ |
| 224 | daemon_over_rsh = 0; |
| 225 | server_options(sargs, &sargc); |
| 226 | |
| 227 | if (sargc >= MAX_ARGS - 2) |
| 228 | goto arg_overflow; |
| 229 | |
| 230 | sargs[sargc++] = "."; |
| 231 | |
| 232 | while (argc > 0) { |
| 233 | if (sargc >= MAX_ARGS - 1) { |
| 234 | arg_overflow: |
| 235 | rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n"); |
| 236 | exit_cleanup(RERR_SYNTAX); |
| 237 | } |
| 238 | sargs[sargc++] = *argv++; |
| 239 | argc--; |
| 240 | } |
| 241 | |
| 242 | sargs[sargc] = NULL; |
| 243 | |
| 244 | if (verbose > 1) |
| 245 | print_child_argv("sending daemon args:", sargs); |
| 246 | |
| 247 | p = strchr(path, '/'); |
| 248 | if (p) *p = '\0'; |
| 249 | io_printf(f_out, "%s\n", path); |
| 250 | if (p) *p = '/'; |
| 251 | |
| 252 | /* Old servers may just drop the connection here, |
| 253 | rather than sending a proper EXIT command. Yuck. */ |
| 254 | kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0; |
| 255 | |
| 256 | while (1) { |
| 257 | if (!read_line_old(f_in, line, sizeof line)) { |
| 258 | rprintf(FERROR, "rsync: didn't get server startup line\n"); |
| 259 | return -1; |
| 260 | } |
| 261 | |
| 262 | if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) { |
| 263 | auth_client(f_out, user, line+18); |
| 264 | continue; |
| 265 | } |
| 266 | |
| 267 | if (strcmp(line,"@RSYNCD: OK") == 0) |
| 268 | break; |
| 269 | |
| 270 | if (strcmp(line,"@RSYNCD: EXIT") == 0) { |
| 271 | /* This is sent by recent versions of the |
| 272 | * server to terminate the listing of modules. |
| 273 | * We don't want to go on and transfer |
| 274 | * anything; just exit. */ |
| 275 | exit(0); |
| 276 | } |
| 277 | |
| 278 | if (strncmp(line, "@ERROR", 6) == 0) { |
| 279 | rprintf(FERROR, "%s\n", line); |
| 280 | /* This is always fatal; the server will now |
| 281 | * close the socket. */ |
| 282 | return -1; |
| 283 | } |
| 284 | |
| 285 | /* This might be a MOTD line or a module listing, but there is |
| 286 | * no way to differentiate it. The manpage mentions this. */ |
| 287 | if (output_motd) |
| 288 | rprintf(FINFO, "%s\n", line); |
| 289 | } |
| 290 | kluge_around_eof = 0; |
| 291 | |
| 292 | if (rl_nulls) { |
| 293 | for (i = 0; i < sargc; i++) { |
| 294 | write_sbuf(f_out, sargs[i]); |
| 295 | write_byte(f_out, 0); |
| 296 | } |
| 297 | write_byte(f_out, 0); |
| 298 | } else { |
| 299 | for (i = 0; i < sargc; i++) |
| 300 | io_printf(f_out, "%s\n", sargs[i]); |
| 301 | write_sbuf(f_out, "\n"); |
| 302 | } |
| 303 | |
| 304 | if (protocol_version < 23) { |
| 305 | if (protocol_version == 22 || !am_sender) |
| 306 | io_start_multiplex_in(); |
| 307 | } |
| 308 | |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | static char *finish_pre_exec(pid_t pid, int fd, char *request, |
| 313 | int argc, char *argv[]) |
| 314 | { |
| 315 | int j, status = -1; |
| 316 | |
| 317 | if (!request) |
| 318 | request = "(NONE)"; |
| 319 | |
| 320 | write_buf(fd, request, strlen(request)+1); |
| 321 | for (j = 0; j < argc; j++) |
| 322 | write_buf(fd, argv[j], strlen(argv[j])+1); |
| 323 | write_byte(fd, 0); |
| 324 | |
| 325 | close(fd); |
| 326 | |
| 327 | if (wait_process(pid, &status, 0) < 0 |
| 328 | || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { |
| 329 | char *e; |
| 330 | if (asprintf(&e, "pre-xfer exec returned failure (%d)%s%s\n", |
| 331 | status, status < 0 ? ": " : "", |
| 332 | status < 0 ? strerror(errno) : "") < 0) |
| 333 | out_of_memory("finish_pre_exec"); |
| 334 | return e; |
| 335 | } |
| 336 | return NULL; |
| 337 | } |
| 338 | |
| 339 | static int read_arg_from_pipe(int fd, char *buf, int limit) |
| 340 | { |
| 341 | char *bp = buf, *eob = buf + limit - 1; |
| 342 | |
| 343 | while (1) { |
| 344 | if (read(fd, bp, 1) != 1) |
| 345 | return -1; |
| 346 | if (*bp == '\0') |
| 347 | break; |
| 348 | if (bp < eob) |
| 349 | bp++; |
| 350 | } |
| 351 | *bp = '\0'; |
| 352 | |
| 353 | return bp - buf; |
| 354 | } |
| 355 | |
| 356 | static int rsync_module(int f_in, int f_out, int i, char *addr, char *host) |
| 357 | { |
| 358 | int argc, opt_cnt; |
| 359 | char **argv; |
| 360 | char line[BIGPATHBUFLEN]; |
| 361 | uid_t uid = (uid_t)-2; /* canonically "nobody" */ |
| 362 | gid_t gid = (gid_t)-2; |
| 363 | char *p, *err_msg = NULL; |
| 364 | char *name = lp_name(i); |
| 365 | int use_chroot = lp_use_chroot(i); |
| 366 | int ret, pre_exec_fd = -1; |
| 367 | pid_t pre_exec_pid = 0; |
| 368 | char *request = NULL; |
| 369 | |
| 370 | if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) { |
| 371 | rprintf(FLOG, "rsync denied on module %s from %s (%s)\n", |
| 372 | name, host, addr); |
| 373 | if (!lp_list(i)) |
| 374 | io_printf(f_out, "@ERROR: Unknown module '%s'\n", name); |
| 375 | else { |
| 376 | io_printf(f_out, |
| 377 | "@ERROR: access denied to %s from %s (%s)\n", |
| 378 | name, host, addr); |
| 379 | } |
| 380 | return -1; |
| 381 | } |
| 382 | |
| 383 | if (am_daemon && am_server) { |
| 384 | rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n", |
| 385 | name, host, addr); |
| 386 | } |
| 387 | |
| 388 | if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) { |
| 389 | if (errno) { |
| 390 | rsyserr(FLOG, errno, "failed to open lock file %s", |
| 391 | lp_lock_file(i)); |
| 392 | io_printf(f_out, "@ERROR: failed to open lock file\n"); |
| 393 | } else { |
| 394 | rprintf(FLOG, "max connections (%d) reached\n", |
| 395 | lp_max_connections(i)); |
| 396 | io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n", |
| 397 | lp_max_connections(i)); |
| 398 | } |
| 399 | return -1; |
| 400 | } |
| 401 | |
| 402 | auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD "); |
| 403 | |
| 404 | if (!auth_user) { |
| 405 | io_printf(f_out, "@ERROR: auth failed on module %s\n", name); |
| 406 | return -1; |
| 407 | } |
| 408 | |
| 409 | module_id = i; |
| 410 | |
| 411 | if (lp_read_only(i)) |
| 412 | read_only = 1; |
| 413 | |
| 414 | if (lp_transfer_logging(i) && !logfile_format) |
| 415 | logfile_format = lp_log_format(i); |
| 416 | if (log_format_has(logfile_format, 'i')) |
| 417 | logfile_format_has_i = 1; |
| 418 | if (logfile_format_has_i || log_format_has(logfile_format, 'o')) |
| 419 | logfile_format_has_o_or_i = 1; |
| 420 | |
| 421 | am_root = (MY_UID() == 0); |
| 422 | |
| 423 | if (am_root) { |
| 424 | p = lp_uid(i); |
| 425 | if (!name_to_uid(p, &uid)) { |
| 426 | if (!isDigit(p)) { |
| 427 | rprintf(FLOG, "Invalid uid %s\n", p); |
| 428 | io_printf(f_out, "@ERROR: invalid uid %s\n", p); |
| 429 | return -1; |
| 430 | } |
| 431 | uid = atoi(p); |
| 432 | } |
| 433 | |
| 434 | p = lp_gid(i); |
| 435 | if (!name_to_gid(p, &gid)) { |
| 436 | if (!isDigit(p)) { |
| 437 | rprintf(FLOG, "Invalid gid %s\n", p); |
| 438 | io_printf(f_out, "@ERROR: invalid gid %s\n", p); |
| 439 | return -1; |
| 440 | } |
| 441 | gid = atoi(p); |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | /* TODO: If we're not root, but the configuration requests |
| 446 | * that we change to some uid other than the current one, then |
| 447 | * log a warning. */ |
| 448 | |
| 449 | /* TODO: Perhaps take a list of gids, and make them into the |
| 450 | * supplementary groups. */ |
| 451 | |
| 452 | /* We do a push_dir() without actually calling chdir() in order |
| 453 | * to make sure that the module's path is absolute. After this |
| 454 | * check, module_dir will be set to an absolute path. */ |
| 455 | module_dir = lp_path(i); |
| 456 | strlcpy(line, curr_dir, sizeof line); |
| 457 | if (!push_dir(module_dir, 1)) |
| 458 | goto chdir_failed; |
| 459 | if (strcmp(curr_dir, module_dir) != 0) |
| 460 | module_dir = strdup(curr_dir); |
| 461 | push_dir(line, 1); /* Restore curr_dir. */ |
| 462 | |
| 463 | if (use_chroot || (module_dirlen = strlen(module_dir)) == 1) { |
| 464 | module_dirlen = 0; |
| 465 | set_filter_dir("/", 1); |
| 466 | } else |
| 467 | set_filter_dir(module_dir, module_dirlen); |
| 468 | |
| 469 | p = lp_filter(i); |
| 470 | parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT, |
| 471 | XFLG_ABS_IF_SLASH); |
| 472 | |
| 473 | p = lp_include_from(i); |
| 474 | parse_filter_file(&server_filter_list, p, MATCHFLG_INCLUDE, |
| 475 | XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS); |
| 476 | |
| 477 | p = lp_include(i); |
| 478 | parse_rule(&server_filter_list, p, |
| 479 | MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT, |
| 480 | XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES); |
| 481 | |
| 482 | p = lp_exclude_from(i); |
| 483 | parse_filter_file(&server_filter_list, p, 0, |
| 484 | XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS); |
| 485 | |
| 486 | p = lp_exclude(i); |
| 487 | parse_rule(&server_filter_list, p, MATCHFLG_WORD_SPLIT, |
| 488 | XFLG_ABS_IF_SLASH | XFLG_OLD_PREFIXES); |
| 489 | |
| 490 | log_init(1); |
| 491 | |
| 492 | #ifdef HAVE_PUTENV |
| 493 | if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) { |
| 494 | char *modname, *modpath, *hostaddr, *hostname, *username; |
| 495 | int status; |
| 496 | if (asprintf(&modname, "RSYNC_MODULE_NAME=%s", name) < 0 |
| 497 | || asprintf(&modpath, "RSYNC_MODULE_PATH=%s", module_dir) < 0 |
| 498 | || asprintf(&hostaddr, "RSYNC_HOST_ADDR=%s", addr) < 0 |
| 499 | || asprintf(&hostname, "RSYNC_HOST_NAME=%s", host) < 0 |
| 500 | || asprintf(&username, "RSYNC_USER_NAME=%s", auth_user) < 0) |
| 501 | out_of_memory("rsync_module"); |
| 502 | putenv(modname); |
| 503 | putenv(modpath); |
| 504 | putenv(hostaddr); |
| 505 | putenv(hostname); |
| 506 | putenv(username); |
| 507 | umask(orig_umask); |
| 508 | /* For post-xfer exec, fork a new process to run the rsync |
| 509 | * daemon while this process waits for the exit status and |
| 510 | * runs the indicated command at that point. */ |
| 511 | if (*lp_postxfer_exec(i)) { |
| 512 | pid_t pid = fork(); |
| 513 | if (pid < 0) { |
| 514 | rsyserr(FLOG, errno, "fork failed"); |
| 515 | io_printf(f_out, "@ERROR: fork failed\n"); |
| 516 | return -1; |
| 517 | } |
| 518 | if (pid) { |
| 519 | if (asprintf(&p, "RSYNC_PID=%ld", (long)pid) > 0) |
| 520 | putenv(p); |
| 521 | if (wait_process(pid, &status, 0) < 0) |
| 522 | status = -1; |
| 523 | if (asprintf(&p, "RSYNC_RAW_STATUS=%d", status) > 0) |
| 524 | putenv(p); |
| 525 | if (WIFEXITED(status)) |
| 526 | status = WEXITSTATUS(status); |
| 527 | else |
| 528 | status = -1; |
| 529 | if (asprintf(&p, "RSYNC_EXIT_STATUS=%d", status) > 0) |
| 530 | putenv(p); |
| 531 | system(lp_postxfer_exec(i)); |
| 532 | _exit(status); |
| 533 | } |
| 534 | } |
| 535 | /* For pre-xfer exec, fork a child process to run the indicated |
| 536 | * command, though it first waits for the parent process to |
| 537 | * send us the user's request via a pipe. */ |
| 538 | if (*lp_prexfer_exec(i)) { |
| 539 | int fds[2]; |
| 540 | if (asprintf(&p, "RSYNC_PID=%ld", (long)getpid()) > 0) |
| 541 | putenv(p); |
| 542 | if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) { |
| 543 | rsyserr(FLOG, errno, "pre-xfer exec preparation failed"); |
| 544 | io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n"); |
| 545 | return -1; |
| 546 | } |
| 547 | if (pre_exec_pid == 0) { |
| 548 | char buf[BIGPATHBUFLEN]; |
| 549 | int j, len; |
| 550 | close(fds[1]); |
| 551 | set_blocking(fds[0]); |
| 552 | len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN); |
| 553 | if (len <= 0) |
| 554 | _exit(1); |
| 555 | if (asprintf(&p, "RSYNC_REQUEST=%s", buf) > 0) |
| 556 | putenv(p); |
| 557 | for (j = 0; ; j++) { |
| 558 | len = read_arg_from_pipe(fds[0], buf, |
| 559 | BIGPATHBUFLEN); |
| 560 | if (len <= 0) { |
| 561 | if (!len) |
| 562 | break; |
| 563 | _exit(1); |
| 564 | } |
| 565 | if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) > 0) |
| 566 | putenv(p); |
| 567 | } |
| 568 | close(fds[0]); |
| 569 | close(STDIN_FILENO); |
| 570 | close(STDOUT_FILENO); |
| 571 | status = system(lp_prexfer_exec(i)); |
| 572 | if (!WIFEXITED(status)) |
| 573 | _exit(1); |
| 574 | _exit(WEXITSTATUS(status)); |
| 575 | } |
| 576 | close(fds[0]); |
| 577 | set_blocking(fds[1]); |
| 578 | pre_exec_fd = fds[1]; |
| 579 | } |
| 580 | umask(0); |
| 581 | } |
| 582 | #endif |
| 583 | |
| 584 | if (use_chroot) { |
| 585 | /* |
| 586 | * XXX: The 'use chroot' flag is a fairly reliable |
| 587 | * source of confusion, because it fails under two |
| 588 | * important circumstances: running as non-root, |
| 589 | * running on Win32 (or possibly others). On the |
| 590 | * other hand, if you are running as root, then it |
| 591 | * might be better to always use chroot. |
| 592 | * |
| 593 | * So, perhaps if we can't chroot we should just issue |
| 594 | * a warning, unless a "require chroot" flag is set, |
| 595 | * in which case we fail. |
| 596 | */ |
| 597 | if (chroot(module_dir)) { |
| 598 | rsyserr(FLOG, errno, "chroot %s failed", module_dir); |
| 599 | io_printf(f_out, "@ERROR: chroot failed\n"); |
| 600 | return -1; |
| 601 | } |
| 602 | if (!push_dir("/", 0)) |
| 603 | goto chdir_failed; |
| 604 | } else { |
| 605 | if (!push_dir(module_dir, 0)) { |
| 606 | chdir_failed: |
| 607 | rsyserr(FLOG, errno, "chdir %s failed\n", module_dir); |
| 608 | io_printf(f_out, "@ERROR: chdir failed\n"); |
| 609 | return -1; |
| 610 | } |
| 611 | sanitize_paths = 1; |
| 612 | } |
| 613 | |
| 614 | if (am_root) { |
| 615 | /* XXXX: You could argue that if the daemon is started |
| 616 | * by a non-root user and they explicitly specify a |
| 617 | * gid, then we should try to change to that gid -- |
| 618 | * this could be possible if it's already in their |
| 619 | * supplementary groups. */ |
| 620 | |
| 621 | /* TODO: Perhaps we need to document that if rsyncd is |
| 622 | * started by somebody other than root it will inherit |
| 623 | * all their supplementary groups. */ |
| 624 | |
| 625 | if (setgid(gid)) { |
| 626 | rsyserr(FLOG, errno, "setgid %d failed", (int)gid); |
| 627 | io_printf(f_out, "@ERROR: setgid failed\n"); |
| 628 | return -1; |
| 629 | } |
| 630 | #ifdef HAVE_SETGROUPS |
| 631 | /* Get rid of any supplementary groups this process |
| 632 | * might have inheristed. */ |
| 633 | if (setgroups(1, &gid)) { |
| 634 | rsyserr(FLOG, errno, "setgroups failed"); |
| 635 | io_printf(f_out, "@ERROR: setgroups failed\n"); |
| 636 | return -1; |
| 637 | } |
| 638 | #endif |
| 639 | |
| 640 | if (setuid(uid)) { |
| 641 | rsyserr(FLOG, errno, "setuid %d failed", (int)uid); |
| 642 | io_printf(f_out, "@ERROR: setuid failed\n"); |
| 643 | return -1; |
| 644 | } |
| 645 | |
| 646 | am_root = (MY_UID() == 0); |
| 647 | } |
| 648 | |
| 649 | if (lp_temp_dir(i) && *lp_temp_dir(i)) { |
| 650 | tmpdir = lp_temp_dir(i); |
| 651 | if (strlen(tmpdir) >= MAXPATHLEN - 10) { |
| 652 | rprintf(FLOG, |
| 653 | "the 'temp dir' value for %s is WAY too long -- ignoring.\n", |
| 654 | name); |
| 655 | tmpdir = NULL; |
| 656 | } |
| 657 | } |
| 658 | |
| 659 | io_printf(f_out, "@RSYNCD: OK\n"); |
| 660 | |
| 661 | opt_cnt = read_args(f_in, name, line, sizeof line, rl_nulls, &argv, &argc, &request); |
| 662 | |
| 663 | if (pre_exec_pid) { |
| 664 | err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request, |
| 665 | opt_cnt, argv); |
| 666 | } |
| 667 | |
| 668 | verbose = 0; /* future verbosity is controlled by client options */ |
| 669 | ret = parse_arguments(&argc, (const char ***) &argv, 0); |
| 670 | am_server = 1; /* Don't let someone try to be tricky. */ |
| 671 | if (lp_ignore_errors(module_id)) |
| 672 | ignore_errors = 1; |
| 673 | |
| 674 | if (lp_fake_super(i)) |
| 675 | am_root = -1; |
| 676 | else if (am_root < 0) /* Treat --fake-super from client as --super. */ |
| 677 | am_root = 2; |
| 678 | |
| 679 | if (filesfrom_fd == 0) |
| 680 | filesfrom_fd = f_in; |
| 681 | |
| 682 | if (request) { |
| 683 | if (*auth_user) { |
| 684 | rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n", |
| 685 | am_sender ? "on" : "to", |
| 686 | request, auth_user, host, addr); |
| 687 | } else { |
| 688 | rprintf(FLOG, "rsync %s %s from %s (%s)\n", |
| 689 | am_sender ? "on" : "to", |
| 690 | request, host, addr); |
| 691 | } |
| 692 | free(request); |
| 693 | } |
| 694 | |
| 695 | #ifndef DEBUG |
| 696 | /* don't allow the logs to be flooded too fast */ |
| 697 | if (verbose > lp_max_verbosity(i)) |
| 698 | verbose = lp_max_verbosity(i); |
| 699 | #endif |
| 700 | |
| 701 | if (protocol_version < 23 |
| 702 | && (protocol_version == 22 || am_sender)) |
| 703 | io_start_multiplex_out(); |
| 704 | else if (!ret || err_msg) { |
| 705 | /* We have to get I/O multiplexing started so that we can |
| 706 | * get the error back to the client. This means getting |
| 707 | * the protocol setup finished first in later versions. */ |
| 708 | setup_protocol(f_out, f_in); |
| 709 | if (!am_sender) { |
| 710 | /* Since we failed in our option parsing, we may not |
| 711 | * have finished parsing that the client sent us a |
| 712 | * --files-from option, so look for it manually. |
| 713 | * Without this, the socket would be in the wrong |
| 714 | * state for the upcoming error message. */ |
| 715 | if (!files_from) { |
| 716 | int i; |
| 717 | for (i = 0; i < argc; i++) { |
| 718 | if (strncmp(argv[i], "--files-from", 12) == 0) { |
| 719 | files_from = ""; |
| 720 | break; |
| 721 | } |
| 722 | } |
| 723 | } |
| 724 | if (files_from) |
| 725 | write_byte(f_out, 0); |
| 726 | } |
| 727 | io_start_multiplex_out(); |
| 728 | } |
| 729 | |
| 730 | if (!ret || err_msg) { |
| 731 | if (err_msg) |
| 732 | rwrite(FERROR, err_msg, strlen(err_msg), 0); |
| 733 | else |
| 734 | option_error(); |
| 735 | msleep(400); |
| 736 | exit_cleanup(RERR_UNSUPPORTED); |
| 737 | } |
| 738 | |
| 739 | if (lp_timeout(i) && lp_timeout(i) > io_timeout) |
| 740 | set_io_timeout(lp_timeout(i)); |
| 741 | |
| 742 | /* If we have some incoming/outgoing chmod changes, append them to |
| 743 | * any user-specified changes (making our changes have priority). |
| 744 | * We also get a pointer to just our changes so that a receiver |
| 745 | * process can use them separately if --perms wasn't specified. */ |
| 746 | if (am_sender) |
| 747 | p = lp_outgoing_chmod(i); |
| 748 | else |
| 749 | p = lp_incoming_chmod(i); |
| 750 | if (*p && !(daemon_chmod_modes = parse_chmod(p, &chmod_modes))) { |
| 751 | rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n", |
| 752 | am_sender ? "outgo" : "incom", p); |
| 753 | } |
| 754 | |
| 755 | start_server(f_in, f_out, argc, argv); |
| 756 | |
| 757 | return 0; |
| 758 | } |
| 759 | |
| 760 | /* send a list of available modules to the client. Don't list those |
| 761 | with "list = False". */ |
| 762 | static void send_listing(int fd) |
| 763 | { |
| 764 | int n = lp_numservices(); |
| 765 | int i; |
| 766 | |
| 767 | for (i = 0; i < n; i++) { |
| 768 | if (lp_list(i)) |
| 769 | io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i)); |
| 770 | } |
| 771 | |
| 772 | if (protocol_version >= 25) |
| 773 | io_printf(fd,"@RSYNCD: EXIT\n"); |
| 774 | } |
| 775 | |
| 776 | /* this is called when a connection is established to a client |
| 777 | and we want to start talking. The setup of the system is done from |
| 778 | here */ |
| 779 | int start_daemon(int f_in, int f_out) |
| 780 | { |
| 781 | char line[1024]; |
| 782 | char *addr, *host; |
| 783 | int i; |
| 784 | |
| 785 | io_set_sock_fds(f_in, f_out); |
| 786 | |
| 787 | /* We must load the config file before calling any function that |
| 788 | * might cause log-file output to occur. This ensures that the |
| 789 | * "log file" param gets honored for the 2 non-forked use-cases |
| 790 | * (when rsync is run by init and run by a remote shell). */ |
| 791 | if (!lp_load(config_file, 0)) |
| 792 | exit_cleanup(RERR_SYNTAX); |
| 793 | |
| 794 | addr = client_addr(f_in); |
| 795 | host = client_name(f_in); |
| 796 | rprintf(FLOG, "connect from %s (%s)\n", host, addr); |
| 797 | |
| 798 | if (!am_server) { |
| 799 | set_socket_options(f_in, "SO_KEEPALIVE"); |
| 800 | if (sockopts) |
| 801 | set_socket_options(f_in, sockopts); |
| 802 | else |
| 803 | set_socket_options(f_in, lp_socket_options()); |
| 804 | set_nonblocking(f_in); |
| 805 | } |
| 806 | |
| 807 | if (exchange_protocols(f_in, f_out, line, sizeof line, 0) < 0) |
| 808 | return -1; |
| 809 | |
| 810 | line[0] = 0; |
| 811 | if (!read_line_old(f_in, line, sizeof line)) |
| 812 | return -1; |
| 813 | |
| 814 | if (!*line || strcmp(line, "#list") == 0) { |
| 815 | rprintf(FLOG, "module-list request from %s (%s)\n", |
| 816 | host, addr); |
| 817 | send_listing(f_out); |
| 818 | return -1; |
| 819 | } |
| 820 | |
| 821 | if (*line == '#') { |
| 822 | /* it's some sort of command that I don't understand */ |
| 823 | io_printf(f_out, "@ERROR: Unknown command '%s'\n", line); |
| 824 | return -1; |
| 825 | } |
| 826 | |
| 827 | if ((i = lp_number(line)) < 0) { |
| 828 | rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n", |
| 829 | line, host, addr); |
| 830 | io_printf(f_out, "@ERROR: Unknown module '%s'\n", line); |
| 831 | return -1; |
| 832 | } |
| 833 | |
| 834 | #ifdef HAVE_SIGACTION |
| 835 | sigact.sa_flags = SA_NOCLDSTOP; |
| 836 | #endif |
| 837 | SIGACTION(SIGCHLD, remember_children); |
| 838 | |
| 839 | return rsync_module(f_in, f_out, i, addr, host); |
| 840 | } |
| 841 | |
| 842 | int daemon_main(void) |
| 843 | { |
| 844 | char *pid_file; |
| 845 | |
| 846 | if (is_a_socket(STDIN_FILENO)) { |
| 847 | int i; |
| 848 | |
| 849 | /* we are running via inetd - close off stdout and |
| 850 | * stderr so that library functions (and getopt) don't |
| 851 | * try to use them. Redirect them to /dev/null */ |
| 852 | for (i = 1; i < 3; i++) { |
| 853 | close(i); |
| 854 | open("/dev/null", O_RDWR); |
| 855 | } |
| 856 | |
| 857 | return start_daemon(STDIN_FILENO, STDIN_FILENO); |
| 858 | } |
| 859 | |
| 860 | if (!no_detach) |
| 861 | become_daemon(); |
| 862 | |
| 863 | if (!lp_load(config_file, 1)) |
| 864 | exit_cleanup(RERR_SYNTAX); |
| 865 | |
| 866 | if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0) |
| 867 | rsync_port = RSYNC_PORT; |
| 868 | if (bind_address == NULL && *lp_bind_address()) |
| 869 | bind_address = lp_bind_address(); |
| 870 | |
| 871 | log_init(0); |
| 872 | |
| 873 | rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n", |
| 874 | RSYNC_VERSION, rsync_port); |
| 875 | /* TODO: If listening on a particular address, then show that |
| 876 | * address too. In fact, why not just do inet_ntop on the |
| 877 | * local address??? */ |
| 878 | |
| 879 | if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) { |
| 880 | char pidbuf[16]; |
| 881 | int fd; |
| 882 | pid_t pid = getpid(); |
| 883 | cleanup_set_pid(pid); |
| 884 | if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC, |
| 885 | 0666 & ~orig_umask)) == -1) { |
| 886 | cleanup_set_pid(0); |
| 887 | rsyserr(FLOG, errno, "failed to create pid file %s", |
| 888 | pid_file); |
| 889 | exit_cleanup(RERR_FILEIO); |
| 890 | } |
| 891 | snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid); |
| 892 | write(fd, pidbuf, strlen(pidbuf)); |
| 893 | close(fd); |
| 894 | } |
| 895 | |
| 896 | start_accept_loop(rsync_port, start_daemon); |
| 897 | return -1; |
| 898 | } |