Annotation of embedaddon/rsync/clientserver.c, revision 1.1
1.1 ! misho 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) 2002-2009 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: #include "ifuncs.h"
! 24:
! 25: extern int quiet;
! 26: extern int verbose;
! 27: extern int dry_run;
! 28: extern int output_motd;
! 29: extern int list_only;
! 30: extern int am_sender;
! 31: extern int am_server;
! 32: extern int am_daemon;
! 33: extern int am_root;
! 34: extern int rsync_port;
! 35: extern int protect_args;
! 36: extern int ignore_errors;
! 37: extern int preserve_xattrs;
! 38: extern int kluge_around_eof;
! 39: extern int daemon_over_rsh;
! 40: extern int sanitize_paths;
! 41: extern int numeric_ids;
! 42: extern int filesfrom_fd;
! 43: extern int remote_protocol;
! 44: extern int protocol_version;
! 45: extern int io_timeout;
! 46: extern int no_detach;
! 47: extern int write_batch;
! 48: extern int default_af_hint;
! 49: extern int logfile_format_has_i;
! 50: extern int logfile_format_has_o_or_i;
! 51: extern mode_t orig_umask;
! 52: extern char *bind_address;
! 53: extern char *config_file;
! 54: extern char *logfile_format;
! 55: extern char *files_from;
! 56: extern char *tmpdir;
! 57: extern struct chmod_mode_struct *chmod_modes;
! 58: extern struct filter_list_struct daemon_filter_list;
! 59: #ifdef ICONV_OPTION
! 60: extern char *iconv_opt;
! 61: extern iconv_t ic_send, ic_recv;
! 62: #endif
! 63:
! 64: char *auth_user;
! 65: int read_only = 0;
! 66: int module_id = -1;
! 67: int munge_symlinks = 0;
! 68: struct chmod_mode_struct *daemon_chmod_modes;
! 69:
! 70: /* module_dirlen is the length of the module_dir string when in daemon
! 71: * mode and module_dir is not "/"; otherwise 0. (Note that a chroot-
! 72: * enabled module can have a non-"/" module_dir these days.) */
! 73: char *module_dir = NULL;
! 74: unsigned int module_dirlen = 0;
! 75:
! 76: char *full_module_path;
! 77:
! 78: static int rl_nulls = 0;
! 79:
! 80: #ifdef HAVE_SIGACTION
! 81: static struct sigaction sigact;
! 82: #endif
! 83:
! 84: /**
! 85: * Run a client connected to an rsyncd. The alternative to this
! 86: * function for remote-shell connections is do_cmd().
! 87: *
! 88: * After negotiating which module to use and reading the server's
! 89: * motd, this hands over to client_run(). Telling the server the
! 90: * module will cause it to chroot/setuid/etc.
! 91: *
! 92: * Instead of doing a transfer, the client may at this stage instead
! 93: * get a listing of remote modules and exit.
! 94: *
! 95: * @return -1 for error in startup, or the result of client_run().
! 96: * Either way, it eventually gets passed to exit_cleanup().
! 97: **/
! 98: int start_socket_client(char *host, int remote_argc, char *remote_argv[],
! 99: int argc, char *argv[])
! 100: {
! 101: int fd, ret;
! 102: char *p, *user = NULL;
! 103:
! 104: /* This is redundant with code in start_inband_exchange(), but this
! 105: * short-circuits a problem in the client before we open a socket,
! 106: * and the extra check won't hurt. */
! 107: if (**remote_argv == '/') {
! 108: rprintf(FERROR,
! 109: "ERROR: The remote path must start with a module name not a /\n");
! 110: return -1;
! 111: }
! 112:
! 113: if ((p = strrchr(host, '@')) != NULL) {
! 114: user = host;
! 115: host = p+1;
! 116: *p = '\0';
! 117: }
! 118:
! 119: fd = open_socket_out_wrapped(host, rsync_port, bind_address,
! 120: default_af_hint);
! 121: if (fd == -1)
! 122: exit_cleanup(RERR_SOCKETIO);
! 123:
! 124: #ifdef ICONV_CONST
! 125: setup_iconv();
! 126: #endif
! 127:
! 128: ret = start_inband_exchange(fd, fd, user, remote_argc, remote_argv);
! 129:
! 130: return ret ? ret : client_run(fd, fd, -1, argc, argv);
! 131: }
! 132:
! 133: static int exchange_protocols(int f_in, int f_out, char *buf, size_t bufsiz, int am_client)
! 134: {
! 135: int remote_sub = -1;
! 136: #if SUBPROTOCOL_VERSION != 0
! 137: int our_sub = protocol_version < PROTOCOL_VERSION ? 0 : SUBPROTOCOL_VERSION;
! 138: #else
! 139: int our_sub = 0;
! 140: #endif
! 141: char *motd;
! 142:
! 143: io_printf(f_out, "@RSYNCD: %d.%d\n", protocol_version, our_sub);
! 144:
! 145: if (!am_client) {
! 146: motd = lp_motd_file();
! 147: if (motd && *motd) {
! 148: FILE *f = fopen(motd,"r");
! 149: while (f && !feof(f)) {
! 150: int len = fread(buf, 1, bufsiz - 1, f);
! 151: if (len > 0)
! 152: write_buf(f_out, buf, len);
! 153: }
! 154: if (f)
! 155: fclose(f);
! 156: write_sbuf(f_out, "\n");
! 157: }
! 158: }
! 159:
! 160: /* This strips the \n. */
! 161: if (!read_line_old(f_in, buf, bufsiz)) {
! 162: if (am_client)
! 163: rprintf(FERROR, "rsync: did not see server greeting\n");
! 164: return -1;
! 165: }
! 166:
! 167: if (sscanf(buf, "@RSYNCD: %d.%d", &remote_protocol, &remote_sub) < 1) {
! 168: if (am_client)
! 169: rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", buf);
! 170: else
! 171: io_printf(f_out, "@ERROR: protocol startup error\n");
! 172: return -1;
! 173: }
! 174:
! 175: if (remote_sub < 0) {
! 176: if (remote_protocol == 30) {
! 177: if (am_client)
! 178: rprintf(FERROR, "rsync: server is speaking an incompatible beta of protocol 30\n");
! 179: else
! 180: io_printf(f_out, "@ERROR: your client is speaking an incompatible beta of protocol 30\n");
! 181: return -1;
! 182: }
! 183: remote_sub = 0;
! 184: }
! 185:
! 186: if (protocol_version > remote_protocol) {
! 187: protocol_version = remote_protocol;
! 188: if (remote_sub)
! 189: protocol_version--;
! 190: } else if (protocol_version == remote_protocol) {
! 191: if (remote_sub != our_sub)
! 192: protocol_version--;
! 193: }
! 194: #if SUBPROTOCOL_VERSION != 0
! 195: else if (protocol_version < remote_protocol) {
! 196: if (our_sub)
! 197: protocol_version--;
! 198: }
! 199: #endif
! 200:
! 201: if (protocol_version >= 30)
! 202: rl_nulls = 1;
! 203:
! 204: return 0;
! 205: }
! 206:
! 207: int start_inband_exchange(int f_in, int f_out, const char *user, int argc, char *argv[])
! 208: {
! 209: int i, modlen;
! 210: char line[BIGPATHBUFLEN];
! 211: char *sargs[MAX_ARGS];
! 212: int sargc = 0;
! 213: char *p, *modname;
! 214:
! 215: assert(argc > 0 && *argv != NULL);
! 216:
! 217: if (**argv == '/') {
! 218: rprintf(FERROR,
! 219: "ERROR: The remote path must start with a module name\n");
! 220: return -1;
! 221: }
! 222:
! 223: if (!(p = strchr(*argv, '/')))
! 224: modlen = strlen(*argv);
! 225: else
! 226: modlen = p - *argv;
! 227:
! 228: if (!(modname = new_array(char, modlen+1+1))) /* room for '/' & '\0' */
! 229: out_of_memory("start_inband_exchange");
! 230: strlcpy(modname, *argv, modlen + 1);
! 231: modname[modlen] = '/';
! 232: modname[modlen+1] = '\0';
! 233:
! 234: if (!user)
! 235: user = getenv("USER");
! 236: if (!user)
! 237: user = getenv("LOGNAME");
! 238:
! 239: if (exchange_protocols(f_in, f_out, line, sizeof line, 1) < 0)
! 240: return -1;
! 241:
! 242: /* set daemon_over_rsh to false since we need to build the
! 243: * true set of args passed through the rsh/ssh connection;
! 244: * this is a no-op for direct-socket-connection mode */
! 245: daemon_over_rsh = 0;
! 246: server_options(sargs, &sargc);
! 247:
! 248: if (sargc >= MAX_ARGS - 2)
! 249: goto arg_overflow;
! 250:
! 251: sargs[sargc++] = ".";
! 252:
! 253: while (argc > 0) {
! 254: if (sargc >= MAX_ARGS - 1) {
! 255: arg_overflow:
! 256: rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n");
! 257: exit_cleanup(RERR_SYNTAX);
! 258: }
! 259: if (strncmp(*argv, modname, modlen) == 0
! 260: && argv[0][modlen] == '\0')
! 261: sargs[sargc++] = modname; /* we send "modname/" */
! 262: else if (**argv == '-') {
! 263: if (asprintf(sargs + sargc++, "./%s", *argv) < 0)
! 264: out_of_memory("start_inband_exchange");
! 265: } else
! 266: sargs[sargc++] = *argv;
! 267: argv++;
! 268: argc--;
! 269: }
! 270:
! 271: sargs[sargc] = NULL;
! 272:
! 273: if (verbose > 1)
! 274: print_child_argv("sending daemon args:", sargs);
! 275:
! 276: io_printf(f_out, "%.*s\n", modlen, modname);
! 277:
! 278: /* Old servers may just drop the connection here,
! 279: rather than sending a proper EXIT command. Yuck. */
! 280: kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
! 281:
! 282: while (1) {
! 283: if (!read_line_old(f_in, line, sizeof line)) {
! 284: rprintf(FERROR, "rsync: didn't get server startup line\n");
! 285: return -1;
! 286: }
! 287:
! 288: if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
! 289: auth_client(f_out, user, line+18);
! 290: continue;
! 291: }
! 292:
! 293: if (strcmp(line,"@RSYNCD: OK") == 0)
! 294: break;
! 295:
! 296: if (strcmp(line,"@RSYNCD: EXIT") == 0) {
! 297: /* This is sent by recent versions of the
! 298: * server to terminate the listing of modules.
! 299: * We don't want to go on and transfer
! 300: * anything; just exit. */
! 301: exit(0);
! 302: }
! 303:
! 304: if (strncmp(line, "@ERROR", 6) == 0) {
! 305: rprintf(FERROR, "%s\n", line);
! 306: /* This is always fatal; the server will now
! 307: * close the socket. */
! 308: return -1;
! 309: }
! 310:
! 311: /* This might be a MOTD line or a module listing, but there is
! 312: * no way to differentiate it. The manpage mentions this. */
! 313: if (output_motd)
! 314: rprintf(FINFO, "%s\n", line);
! 315: }
! 316: kluge_around_eof = 0;
! 317:
! 318: if (rl_nulls) {
! 319: for (i = 0; i < sargc; i++) {
! 320: if (!sargs[i]) /* stop at --protect-args NULL */
! 321: break;
! 322: write_sbuf(f_out, sargs[i]);
! 323: write_byte(f_out, 0);
! 324: }
! 325: write_byte(f_out, 0);
! 326: } else {
! 327: for (i = 0; i < sargc; i++)
! 328: io_printf(f_out, "%s\n", sargs[i]);
! 329: write_sbuf(f_out, "\n");
! 330: }
! 331:
! 332: if (protect_args)
! 333: send_protected_args(f_out, sargs);
! 334:
! 335: if (protocol_version < 23) {
! 336: if (protocol_version == 22 || !am_sender)
! 337: io_start_multiplex_in();
! 338: }
! 339:
! 340: free(modname);
! 341:
! 342: return 0;
! 343: }
! 344:
! 345: static char *finish_pre_exec(pid_t pid, int fd, char *request,
! 346: char **early_argv, char **argv)
! 347: {
! 348: int j = 0, status = -1;
! 349:
! 350: if (!request)
! 351: request = "(NONE)";
! 352:
! 353: write_buf(fd, request, strlen(request)+1);
! 354: if (early_argv) {
! 355: for ( ; *early_argv; early_argv++)
! 356: write_buf(fd, *early_argv, strlen(*early_argv)+1);
! 357: j = 1; /* Skip arg0 name in argv. */
! 358: }
! 359: for ( ; argv[j]; j++) {
! 360: write_buf(fd, argv[j], strlen(argv[j])+1);
! 361: if (argv[j][0] == '.' && argv[j][1] == '\0')
! 362: break;
! 363: }
! 364: write_byte(fd, 0);
! 365:
! 366: close(fd);
! 367:
! 368: if (wait_process(pid, &status, 0) < 0
! 369: || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
! 370: char *e;
! 371: if (asprintf(&e, "pre-xfer exec returned failure (%d)%s%s\n",
! 372: status, status < 0 ? ": " : "",
! 373: status < 0 ? strerror(errno) : "") < 0)
! 374: out_of_memory("finish_pre_exec");
! 375: return e;
! 376: }
! 377: return NULL;
! 378: }
! 379:
! 380: static int read_arg_from_pipe(int fd, char *buf, int limit)
! 381: {
! 382: char *bp = buf, *eob = buf + limit - 1;
! 383:
! 384: while (1) {
! 385: int got = read(fd, bp, 1);
! 386: if (got != 1) {
! 387: if (got < 0 && errno == EINTR)
! 388: continue;
! 389: return -1;
! 390: }
! 391: if (*bp == '\0')
! 392: break;
! 393: if (bp < eob)
! 394: bp++;
! 395: }
! 396: *bp = '\0';
! 397:
! 398: return bp - buf;
! 399: }
! 400:
! 401: static int path_failure(int f_out, const char *dir, BOOL was_chdir)
! 402: {
! 403: if (was_chdir)
! 404: rsyserr(FLOG, errno, "chdir %s failed\n", dir);
! 405: else
! 406: rprintf(FLOG, "normalize_path(%s) failed\n", dir);
! 407: io_printf(f_out, "@ERROR: chdir failed\n");
! 408: return -1;
! 409: }
! 410:
! 411: static int rsync_module(int f_in, int f_out, int i, char *addr, char *host)
! 412: {
! 413: int argc;
! 414: char **argv, **orig_argv, **orig_early_argv, *module_chdir;
! 415: char line[BIGPATHBUFLEN];
! 416: uid_t uid = (uid_t)-2; /* canonically "nobody" */
! 417: gid_t gid = (gid_t)-2;
! 418: char *p, *err_msg = NULL;
! 419: char *name = lp_name(i);
! 420: int use_chroot = lp_use_chroot(i);
! 421: int ret, pre_exec_fd = -1;
! 422: pid_t pre_exec_pid = 0;
! 423: char *request = NULL;
! 424:
! 425: #ifdef ICONV_OPTION
! 426: iconv_opt = lp_charset(i);
! 427: if (*iconv_opt)
! 428: setup_iconv();
! 429: iconv_opt = NULL;
! 430: #endif
! 431:
! 432: if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
! 433: rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
! 434: name, host, addr);
! 435: if (!lp_list(i))
! 436: io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
! 437: else {
! 438: io_printf(f_out,
! 439: "@ERROR: access denied to %s from %s (%s)\n",
! 440: name, host, addr);
! 441: }
! 442: return -1;
! 443: }
! 444:
! 445: if (am_daemon && am_server) {
! 446: rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
! 447: name, host, addr);
! 448: }
! 449:
! 450: if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
! 451: if (errno) {
! 452: rsyserr(FLOG, errno, "failed to open lock file %s",
! 453: lp_lock_file(i));
! 454: io_printf(f_out, "@ERROR: failed to open lock file\n");
! 455: } else {
! 456: rprintf(FLOG, "max connections (%d) reached\n",
! 457: lp_max_connections(i));
! 458: io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
! 459: lp_max_connections(i));
! 460: }
! 461: return -1;
! 462: }
! 463:
! 464: auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
! 465:
! 466: if (!auth_user) {
! 467: io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
! 468: return -1;
! 469: }
! 470:
! 471: module_id = i;
! 472:
! 473: if (lp_read_only(i))
! 474: read_only = 1;
! 475:
! 476: if (lp_transfer_logging(i) && !logfile_format)
! 477: logfile_format = lp_log_format(i);
! 478: if (log_format_has(logfile_format, 'i'))
! 479: logfile_format_has_i = 1;
! 480: if (logfile_format_has_i || log_format_has(logfile_format, 'o'))
! 481: logfile_format_has_o_or_i = 1;
! 482:
! 483: am_root = (MY_UID() == 0);
! 484:
! 485: if (am_root) {
! 486: p = lp_uid(i);
! 487: if (!name_to_uid(p, &uid)) {
! 488: if (!isDigit(p)) {
! 489: rprintf(FLOG, "Invalid uid %s\n", p);
! 490: io_printf(f_out, "@ERROR: invalid uid %s\n", p);
! 491: return -1;
! 492: }
! 493: uid = atoi(p);
! 494: }
! 495:
! 496: p = lp_gid(i);
! 497: if (!name_to_gid(p, &gid)) {
! 498: if (!isDigit(p)) {
! 499: rprintf(FLOG, "Invalid gid %s\n", p);
! 500: io_printf(f_out, "@ERROR: invalid gid %s\n", p);
! 501: return -1;
! 502: }
! 503: gid = atoi(p);
! 504: }
! 505: }
! 506:
! 507: /* TODO: If we're not root, but the configuration requests
! 508: * that we change to some uid other than the current one, then
! 509: * log a warning. */
! 510:
! 511: /* TODO: Perhaps take a list of gids, and make them into the
! 512: * supplementary groups. */
! 513:
! 514: module_dir = lp_path(i);
! 515: if (*module_dir == '\0') {
! 516: rprintf(FLOG, "No path specified for module %s\n", name);
! 517: io_printf(f_out, "@ERROR: no path setting.\n");
! 518: return -1;
! 519: }
! 520: if (use_chroot) {
! 521: if ((p = strstr(module_dir, "/./")) != NULL) {
! 522: *p = '\0'; /* Temporary... */
! 523: if (!(module_chdir = normalize_path(module_dir, True, NULL)))
! 524: return path_failure(f_out, module_dir, False);
! 525: *p = '/';
! 526: if (!(p = normalize_path(p + 2, True, &module_dirlen)))
! 527: return path_failure(f_out, strstr(module_dir, "/./"), False);
! 528: if (!(full_module_path = normalize_path(module_dir, False, NULL)))
! 529: full_module_path = module_dir;
! 530: module_dir = p;
! 531: } else {
! 532: if (!(module_chdir = normalize_path(module_dir, False, NULL)))
! 533: return path_failure(f_out, module_dir, False);
! 534: full_module_path = module_chdir;
! 535: module_dir = "/";
! 536: module_dirlen = 1;
! 537: }
! 538: } else {
! 539: if (!(module_chdir = normalize_path(module_dir, False, &module_dirlen)))
! 540: return path_failure(f_out, module_dir, False);
! 541: full_module_path = module_dir = module_chdir;
! 542: }
! 543:
! 544: if (module_dirlen == 1) {
! 545: module_dirlen = 0;
! 546: set_filter_dir("/", 1);
! 547: } else
! 548: set_filter_dir(module_dir, module_dirlen);
! 549:
! 550: p = lp_filter(i);
! 551: parse_rule(&daemon_filter_list, p, MATCHFLG_WORD_SPLIT,
! 552: XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3);
! 553:
! 554: p = lp_include_from(i);
! 555: parse_filter_file(&daemon_filter_list, p, MATCHFLG_INCLUDE,
! 556: XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
! 557:
! 558: p = lp_include(i);
! 559: parse_rule(&daemon_filter_list, p,
! 560: MATCHFLG_INCLUDE | MATCHFLG_WORD_SPLIT,
! 561: XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES);
! 562:
! 563: p = lp_exclude_from(i);
! 564: parse_filter_file(&daemon_filter_list, p, 0,
! 565: XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
! 566:
! 567: p = lp_exclude(i);
! 568: parse_rule(&daemon_filter_list, p, MATCHFLG_WORD_SPLIT,
! 569: XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES);
! 570:
! 571: log_init(1);
! 572:
! 573: #ifdef HAVE_PUTENV
! 574: if (*lp_prexfer_exec(i) || *lp_postxfer_exec(i)) {
! 575: char *modname, *modpath, *hostaddr, *hostname, *username;
! 576: int status;
! 577:
! 578: if (asprintf(&modname, "RSYNC_MODULE_NAME=%s", name) < 0
! 579: || asprintf(&modpath, "RSYNC_MODULE_PATH=%s", full_module_path) < 0
! 580: || asprintf(&hostaddr, "RSYNC_HOST_ADDR=%s", addr) < 0
! 581: || asprintf(&hostname, "RSYNC_HOST_NAME=%s", host) < 0
! 582: || asprintf(&username, "RSYNC_USER_NAME=%s", auth_user) < 0)
! 583: out_of_memory("rsync_module");
! 584: putenv(modname);
! 585: putenv(modpath);
! 586: putenv(hostaddr);
! 587: putenv(hostname);
! 588: putenv(username);
! 589: umask(orig_umask);
! 590: /* For post-xfer exec, fork a new process to run the rsync
! 591: * daemon while this process waits for the exit status and
! 592: * runs the indicated command at that point. */
! 593: if (*lp_postxfer_exec(i)) {
! 594: pid_t pid = fork();
! 595: if (pid < 0) {
! 596: rsyserr(FLOG, errno, "fork failed");
! 597: io_printf(f_out, "@ERROR: fork failed\n");
! 598: return -1;
! 599: }
! 600: if (pid) {
! 601: if (asprintf(&p, "RSYNC_PID=%ld", (long)pid) > 0)
! 602: putenv(p);
! 603: if (wait_process(pid, &status, 0) < 0)
! 604: status = -1;
! 605: if (asprintf(&p, "RSYNC_RAW_STATUS=%d", status) > 0)
! 606: putenv(p);
! 607: if (WIFEXITED(status))
! 608: status = WEXITSTATUS(status);
! 609: else
! 610: status = -1;
! 611: if (asprintf(&p, "RSYNC_EXIT_STATUS=%d", status) > 0)
! 612: putenv(p);
! 613: if (system(lp_postxfer_exec(i)) < 0)
! 614: status = -1;
! 615: _exit(status);
! 616: }
! 617: }
! 618: /* For pre-xfer exec, fork a child process to run the indicated
! 619: * command, though it first waits for the parent process to
! 620: * send us the user's request via a pipe. */
! 621: if (*lp_prexfer_exec(i)) {
! 622: int fds[2];
! 623: if (asprintf(&p, "RSYNC_PID=%ld", (long)getpid()) > 0)
! 624: putenv(p);
! 625: if (pipe(fds) < 0 || (pre_exec_pid = fork()) < 0) {
! 626: rsyserr(FLOG, errno, "pre-xfer exec preparation failed");
! 627: io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n");
! 628: return -1;
! 629: }
! 630: if (pre_exec_pid == 0) {
! 631: char buf[BIGPATHBUFLEN];
! 632: int j, len;
! 633: close(fds[1]);
! 634: set_blocking(fds[0]);
! 635: len = read_arg_from_pipe(fds[0], buf, BIGPATHBUFLEN);
! 636: if (len <= 0)
! 637: _exit(1);
! 638: if (asprintf(&p, "RSYNC_REQUEST=%s", buf) > 0)
! 639: putenv(p);
! 640: for (j = 0; ; j++) {
! 641: len = read_arg_from_pipe(fds[0], buf,
! 642: BIGPATHBUFLEN);
! 643: if (len <= 0) {
! 644: if (!len)
! 645: break;
! 646: _exit(1);
! 647: }
! 648: if (asprintf(&p, "RSYNC_ARG%d=%s", j, buf) > 0)
! 649: putenv(p);
! 650: }
! 651: close(fds[0]);
! 652: close(STDIN_FILENO);
! 653: close(STDOUT_FILENO);
! 654: status = system(lp_prexfer_exec(i));
! 655: if (!WIFEXITED(status))
! 656: _exit(1);
! 657: _exit(WEXITSTATUS(status));
! 658: }
! 659: close(fds[0]);
! 660: set_blocking(fds[1]);
! 661: pre_exec_fd = fds[1];
! 662: }
! 663: umask(0);
! 664: }
! 665: #endif
! 666:
! 667: if (use_chroot) {
! 668: /*
! 669: * XXX: The 'use chroot' flag is a fairly reliable
! 670: * source of confusion, because it fails under two
! 671: * important circumstances: running as non-root,
! 672: * running on Win32 (or possibly others). On the
! 673: * other hand, if you are running as root, then it
! 674: * might be better to always use chroot.
! 675: *
! 676: * So, perhaps if we can't chroot we should just issue
! 677: * a warning, unless a "require chroot" flag is set,
! 678: * in which case we fail.
! 679: */
! 680: if (chroot(module_chdir)) {
! 681: rsyserr(FLOG, errno, "chroot %s failed", module_chdir);
! 682: io_printf(f_out, "@ERROR: chroot failed\n");
! 683: return -1;
! 684: }
! 685: module_chdir = module_dir;
! 686: }
! 687:
! 688: if (!change_dir(module_chdir, CD_NORMAL))
! 689: return path_failure(f_out, module_chdir, True);
! 690: if (module_dirlen || !use_chroot)
! 691: sanitize_paths = 1;
! 692:
! 693: if ((munge_symlinks = lp_munge_symlinks(i)) < 0)
! 694: munge_symlinks = !use_chroot || module_dirlen;
! 695: if (munge_symlinks) {
! 696: STRUCT_STAT st;
! 697: if (do_stat(SYMLINK_PREFIX, &st) == 0 && S_ISDIR(st.st_mode)) {
! 698: rprintf(FLOG, "Symlink munging is unsupported when a %s directory exists.\n",
! 699: SYMLINK_PREFIX);
! 700: io_printf(f_out, "@ERROR: daemon security issue -- contact admin\n", name);
! 701: exit_cleanup(RERR_UNSUPPORTED);
! 702: }
! 703: }
! 704:
! 705: if (am_root) {
! 706: /* XXXX: You could argue that if the daemon is started
! 707: * by a non-root user and they explicitly specify a
! 708: * gid, then we should try to change to that gid --
! 709: * this could be possible if it's already in their
! 710: * supplementary groups. */
! 711:
! 712: /* TODO: Perhaps we need to document that if rsyncd is
! 713: * started by somebody other than root it will inherit
! 714: * all their supplementary groups. */
! 715:
! 716: if (setgid(gid)) {
! 717: rsyserr(FLOG, errno, "setgid %d failed", (int)gid);
! 718: io_printf(f_out, "@ERROR: setgid failed\n");
! 719: return -1;
! 720: }
! 721: #ifdef HAVE_SETGROUPS
! 722: /* Get rid of any supplementary groups this process
! 723: * might have inheristed. */
! 724: if (setgroups(1, &gid)) {
! 725: rsyserr(FLOG, errno, "setgroups failed");
! 726: io_printf(f_out, "@ERROR: setgroups failed\n");
! 727: return -1;
! 728: }
! 729: #endif
! 730:
! 731: if (setuid(uid) < 0
! 732: #ifdef HAVE_SETEUID
! 733: || seteuid(uid) < 0
! 734: #endif
! 735: ) {
! 736: rsyserr(FLOG, errno, "setuid %d failed", (int)uid);
! 737: io_printf(f_out, "@ERROR: setuid failed\n");
! 738: return -1;
! 739: }
! 740:
! 741: am_root = (MY_UID() == 0);
! 742: }
! 743:
! 744: if (lp_temp_dir(i) && *lp_temp_dir(i)) {
! 745: tmpdir = lp_temp_dir(i);
! 746: if (strlen(tmpdir) >= MAXPATHLEN - 10) {
! 747: rprintf(FLOG,
! 748: "the 'temp dir' value for %s is WAY too long -- ignoring.\n",
! 749: name);
! 750: tmpdir = NULL;
! 751: }
! 752: }
! 753:
! 754: io_printf(f_out, "@RSYNCD: OK\n");
! 755:
! 756: read_args(f_in, name, line, sizeof line, rl_nulls, &argv, &argc, &request);
! 757: orig_argv = argv;
! 758:
! 759: verbose = 0; /* future verbosity is controlled by client options */
! 760: ret = parse_arguments(&argc, (const char ***) &argv);
! 761: if (protect_args && ret) {
! 762: orig_early_argv = orig_argv;
! 763: protect_args = 2;
! 764: read_args(f_in, name, line, sizeof line, 1, &argv, &argc, &request);
! 765: orig_argv = argv;
! 766: ret = parse_arguments(&argc, (const char ***) &argv);
! 767: } else
! 768: orig_early_argv = NULL;
! 769:
! 770: if (pre_exec_pid) {
! 771: err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request,
! 772: orig_early_argv, orig_argv);
! 773: }
! 774:
! 775: if (orig_early_argv)
! 776: free(orig_early_argv);
! 777:
! 778: am_server = 1; /* Don't let someone try to be tricky. */
! 779: quiet = 0;
! 780: if (lp_ignore_errors(module_id))
! 781: ignore_errors = 1;
! 782: if (write_batch < 0)
! 783: dry_run = 1;
! 784:
! 785: if (lp_fake_super(i)) {
! 786: if (preserve_xattrs > 1)
! 787: preserve_xattrs = 1;
! 788: am_root = -1;
! 789: } else if (am_root < 0) /* Treat --fake-super from client as --super. */
! 790: am_root = 2;
! 791:
! 792: if (filesfrom_fd == 0)
! 793: filesfrom_fd = f_in;
! 794:
! 795: if (request) {
! 796: if (*auth_user) {
! 797: rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n",
! 798: am_sender ? "on" : "to",
! 799: request, auth_user, host, addr);
! 800: } else {
! 801: rprintf(FLOG, "rsync %s %s from %s (%s)\n",
! 802: am_sender ? "on" : "to",
! 803: request, host, addr);
! 804: }
! 805: free(request);
! 806: }
! 807:
! 808: #ifndef DEBUG
! 809: /* don't allow the logs to be flooded too fast */
! 810: if (verbose > lp_max_verbosity(i))
! 811: verbose = lp_max_verbosity(i);
! 812: #endif
! 813:
! 814: if (protocol_version < 23
! 815: && (protocol_version == 22 || am_sender))
! 816: io_start_multiplex_out();
! 817: else if (!ret || err_msg) {
! 818: /* We have to get I/O multiplexing started so that we can
! 819: * get the error back to the client. This means getting
! 820: * the protocol setup finished first in later versions. */
! 821: setup_protocol(f_out, f_in);
! 822: if (!am_sender) {
! 823: /* Since we failed in our option parsing, we may not
! 824: * have finished parsing that the client sent us a
! 825: * --files-from option, so look for it manually.
! 826: * Without this, the socket would be in the wrong
! 827: * state for the upcoming error message. */
! 828: if (!files_from) {
! 829: int i;
! 830: for (i = 0; i < argc; i++) {
! 831: if (strncmp(argv[i], "--files-from", 12) == 0) {
! 832: files_from = "";
! 833: break;
! 834: }
! 835: }
! 836: }
! 837: if (files_from)
! 838: write_byte(f_out, 0);
! 839: }
! 840: io_start_multiplex_out();
! 841: }
! 842:
! 843: if (!ret || err_msg) {
! 844: if (err_msg)
! 845: rwrite(FERROR, err_msg, strlen(err_msg), 0);
! 846: else
! 847: option_error();
! 848: msleep(400);
! 849: exit_cleanup(RERR_UNSUPPORTED);
! 850: }
! 851:
! 852: #ifdef ICONV_OPTION
! 853: if (!iconv_opt) {
! 854: if (ic_send != (iconv_t)-1) {
! 855: iconv_close(ic_send);
! 856: ic_send = (iconv_t)-1;
! 857: }
! 858: if (ic_recv != (iconv_t)-1) {
! 859: iconv_close(ic_recv);
! 860: ic_recv = (iconv_t)-1;
! 861: }
! 862: }
! 863: #endif
! 864:
! 865: if (!numeric_ids
! 866: && (use_chroot ? lp_numeric_ids(i) != False : lp_numeric_ids(i) == True))
! 867: numeric_ids = -1; /* Set --numeric-ids w/o breaking protocol. */
! 868:
! 869: if (lp_timeout(i) && (!io_timeout || lp_timeout(i) < io_timeout))
! 870: set_io_timeout(lp_timeout(i));
! 871:
! 872: /* If we have some incoming/outgoing chmod changes, append them to
! 873: * any user-specified changes (making our changes have priority).
! 874: * We also get a pointer to just our changes so that a receiver
! 875: * process can use them separately if --perms wasn't specified. */
! 876: if (am_sender)
! 877: p = lp_outgoing_chmod(i);
! 878: else
! 879: p = lp_incoming_chmod(i);
! 880: if (*p && !(daemon_chmod_modes = parse_chmod(p, &chmod_modes))) {
! 881: rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n",
! 882: am_sender ? "outgo" : "incom", p);
! 883: }
! 884:
! 885: start_server(f_in, f_out, argc, argv);
! 886:
! 887: return 0;
! 888: }
! 889:
! 890: /* send a list of available modules to the client. Don't list those
! 891: with "list = False". */
! 892: static void send_listing(int fd)
! 893: {
! 894: int n = lp_numservices();
! 895: int i;
! 896:
! 897: for (i = 0; i < n; i++) {
! 898: if (lp_list(i))
! 899: io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
! 900: }
! 901:
! 902: if (protocol_version >= 25)
! 903: io_printf(fd,"@RSYNCD: EXIT\n");
! 904: }
! 905:
! 906: static int load_config(int globals_only)
! 907: {
! 908: if (!config_file) {
! 909: if (am_server && am_root <= 0)
! 910: config_file = RSYNCD_USERCONF;
! 911: else
! 912: config_file = RSYNCD_SYSCONF;
! 913: }
! 914: return lp_load(config_file, globals_only);
! 915: }
! 916:
! 917: /* this is called when a connection is established to a client
! 918: and we want to start talking. The setup of the system is done from
! 919: here */
! 920: int start_daemon(int f_in, int f_out)
! 921: {
! 922: char line[1024];
! 923: char *addr, *host;
! 924: int i;
! 925:
! 926: io_set_sock_fds(f_in, f_out);
! 927:
! 928: /* We must load the config file before calling any function that
! 929: * might cause log-file output to occur. This ensures that the
! 930: * "log file" param gets honored for the 2 non-forked use-cases
! 931: * (when rsync is run by init and run by a remote shell). */
! 932: if (!load_config(0))
! 933: exit_cleanup(RERR_SYNTAX);
! 934:
! 935: addr = client_addr(f_in);
! 936: host = client_name(f_in);
! 937: rprintf(FLOG, "connect from %s (%s)\n", host, addr);
! 938:
! 939: if (!am_server) {
! 940: set_socket_options(f_in, "SO_KEEPALIVE");
! 941: set_nonblocking(f_in);
! 942: }
! 943:
! 944: if (exchange_protocols(f_in, f_out, line, sizeof line, 0) < 0)
! 945: return -1;
! 946:
! 947: line[0] = 0;
! 948: if (!read_line_old(f_in, line, sizeof line))
! 949: return -1;
! 950:
! 951: if (!*line || strcmp(line, "#list") == 0) {
! 952: rprintf(FLOG, "module-list request from %s (%s)\n",
! 953: host, addr);
! 954: send_listing(f_out);
! 955: return -1;
! 956: }
! 957:
! 958: if (*line == '#') {
! 959: /* it's some sort of command that I don't understand */
! 960: io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
! 961: return -1;
! 962: }
! 963:
! 964: if ((i = lp_number(line)) < 0) {
! 965: rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n",
! 966: line, host, addr);
! 967: io_printf(f_out, "@ERROR: Unknown module '%s'\n", line);
! 968: return -1;
! 969: }
! 970:
! 971: #ifdef HAVE_SIGACTION
! 972: sigact.sa_flags = SA_NOCLDSTOP;
! 973: #endif
! 974: SIGACTION(SIGCHLD, remember_children);
! 975:
! 976: return rsync_module(f_in, f_out, i, addr, host);
! 977: }
! 978:
! 979: static void create_pid_file(void)
! 980: {
! 981: char *pid_file = lp_pid_file();
! 982: char pidbuf[16];
! 983: pid_t pid = getpid();
! 984: int fd, len;
! 985:
! 986: if (!pid_file || !*pid_file)
! 987: return;
! 988:
! 989: cleanup_set_pid(pid);
! 990: if ((fd = do_open(pid_file, O_WRONLY|O_CREAT|O_EXCL, 0666 & ~orig_umask)) == -1) {
! 991: failure:
! 992: cleanup_set_pid(0);
! 993: fprintf(stderr, "failed to create pid file %s: %s\n", pid_file, strerror(errno));
! 994: rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
! 995: exit_cleanup(RERR_FILEIO);
! 996: }
! 997: snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid);
! 998: len = strlen(pidbuf);
! 999: if (write(fd, pidbuf, len) != len)
! 1000: goto failure;
! 1001: close(fd);
! 1002: }
! 1003:
! 1004: /* Become a daemon, discarding the controlling terminal. */
! 1005: static void become_daemon(void)
! 1006: {
! 1007: int i;
! 1008: pid_t pid = fork();
! 1009:
! 1010: if (pid) {
! 1011: if (pid < 0) {
! 1012: fprintf(stderr, "failed to fork: %s\n", strerror(errno));
! 1013: exit_cleanup(RERR_FILEIO);
! 1014: }
! 1015: _exit(0);
! 1016: }
! 1017:
! 1018: create_pid_file();
! 1019:
! 1020: /* detach from the terminal */
! 1021: #ifdef HAVE_SETSID
! 1022: setsid();
! 1023: #elif defined TIOCNOTTY
! 1024: i = open("/dev/tty", O_RDWR);
! 1025: if (i >= 0) {
! 1026: ioctl(i, (int)TIOCNOTTY, (char *)0);
! 1027: close(i);
! 1028: }
! 1029: #endif
! 1030: /* make sure that stdin, stdout an stderr don't stuff things
! 1031: * up (library functions, for example) */
! 1032: for (i = 0; i < 3; i++) {
! 1033: close(i);
! 1034: open("/dev/null", O_RDWR);
! 1035: }
! 1036: }
! 1037:
! 1038: int daemon_main(void)
! 1039: {
! 1040: if (is_a_socket(STDIN_FILENO)) {
! 1041: int i;
! 1042:
! 1043: /* we are running via inetd - close off stdout and
! 1044: * stderr so that library functions (and getopt) don't
! 1045: * try to use them. Redirect them to /dev/null */
! 1046: for (i = 1; i < 3; i++) {
! 1047: close(i);
! 1048: open("/dev/null", O_RDWR);
! 1049: }
! 1050:
! 1051: return start_daemon(STDIN_FILENO, STDIN_FILENO);
! 1052: }
! 1053:
! 1054: if (!load_config(1)) {
! 1055: fprintf(stderr, "Failed to parse config file: %s\n", config_file);
! 1056: exit_cleanup(RERR_SYNTAX);
! 1057: }
! 1058:
! 1059: if (no_detach)
! 1060: create_pid_file();
! 1061: else
! 1062: become_daemon();
! 1063:
! 1064: if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0)
! 1065: rsync_port = RSYNC_PORT;
! 1066: if (bind_address == NULL && *lp_bind_address())
! 1067: bind_address = lp_bind_address();
! 1068:
! 1069: log_init(0);
! 1070:
! 1071: rprintf(FLOG, "rsyncd version %s starting, listening on port %d\n",
! 1072: RSYNC_VERSION, rsync_port);
! 1073: /* TODO: If listening on a particular address, then show that
! 1074: * address too. In fact, why not just do getnameinfo on the
! 1075: * local address??? */
! 1076:
! 1077: start_accept_loop(rsync_port, start_daemon);
! 1078: return -1;
! 1079: }
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