| 1 | /* |
| 2 | Copyright (C) Andrew Tridgell 1998 |
| 3 | |
| 4 | This program is free software; you can redistribute it and/or modify |
| 5 | it under the terms of the GNU General Public License as published by |
| 6 | the Free Software Foundation; either version 2 of the License, or |
| 7 | (at your option) any later version. |
| 8 | |
| 9 | This program is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | GNU General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License |
| 15 | along with this program; if not, write to the Free Software |
| 16 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 17 | */ |
| 18 | |
| 19 | /* the socket based protocol for setting up a connection wit rsyncd */ |
| 20 | |
| 21 | #include "rsync.h" |
| 22 | |
| 23 | extern int module_id; |
| 24 | extern int read_only; |
| 25 | extern int verbose; |
| 26 | extern int rsync_port; |
| 27 | |
| 28 | int start_socket_client(char *host, char *path, int argc, char *argv[]) |
| 29 | { |
| 30 | int fd, i; |
| 31 | char *sargs[MAX_ARGS]; |
| 32 | int sargc=0; |
| 33 | char line[MAXPATHLEN]; |
| 34 | char *p, *user=NULL; |
| 35 | extern int remote_version; |
| 36 | extern int am_client; |
| 37 | extern int am_sender; |
| 38 | |
| 39 | p = strchr(host, '@'); |
| 40 | if (p) { |
| 41 | user = host; |
| 42 | host = p+1; |
| 43 | *p = 0; |
| 44 | } |
| 45 | |
| 46 | if (!user) user = getenv("USER"); |
| 47 | if (!user) user = getenv("LOGNAME"); |
| 48 | |
| 49 | am_client = 1; |
| 50 | |
| 51 | fd = open_socket_out(host, rsync_port); |
| 52 | if (fd == -1) { |
| 53 | exit_cleanup(1); |
| 54 | } |
| 55 | |
| 56 | server_options(sargs,&sargc); |
| 57 | |
| 58 | sargs[sargc++] = "."; |
| 59 | |
| 60 | if (path && *path) |
| 61 | sargs[sargc++] = path; |
| 62 | |
| 63 | sargs[sargc] = NULL; |
| 64 | |
| 65 | io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION); |
| 66 | |
| 67 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 68 | return -1; |
| 69 | } |
| 70 | |
| 71 | if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) { |
| 72 | return -1; |
| 73 | } |
| 74 | |
| 75 | p = strchr(path,'/'); |
| 76 | if (p) *p = 0; |
| 77 | io_printf(fd,"%s\n",path); |
| 78 | if (p) *p = '/'; |
| 79 | |
| 80 | while (1) { |
| 81 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 82 | return -1; |
| 83 | } |
| 84 | |
| 85 | if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) { |
| 86 | auth_client(fd, user, line+18); |
| 87 | continue; |
| 88 | } |
| 89 | |
| 90 | if (strcmp(line,"@RSYNCD: OK") == 0) break; |
| 91 | rprintf(FINFO,"%s\n", line); |
| 92 | } |
| 93 | |
| 94 | for (i=0;i<sargc;i++) { |
| 95 | io_printf(fd,"%s\n", sargs[i]); |
| 96 | } |
| 97 | io_printf(fd,"\n"); |
| 98 | |
| 99 | if (remote_version > 17 && !am_sender) |
| 100 | io_start_multiplex_in(fd); |
| 101 | |
| 102 | return client_run(fd, fd, -1, argc, argv); |
| 103 | } |
| 104 | |
| 105 | |
| 106 | |
| 107 | static int rsync_module(int fd, int i) |
| 108 | { |
| 109 | int argc=0; |
| 110 | char *argv[MAX_ARGS]; |
| 111 | char **argp; |
| 112 | char line[MAXPATHLEN]; |
| 113 | uid_t uid = (uid_t)-2; |
| 114 | gid_t gid = (gid_t)-2; |
| 115 | char *p; |
| 116 | char *addr = client_addr(fd); |
| 117 | char *host = client_name(fd); |
| 118 | char *name = lp_name(i); |
| 119 | char *user; |
| 120 | int start_glob=0; |
| 121 | int ret; |
| 122 | char *request=NULL; |
| 123 | extern int am_sender; |
| 124 | extern int remote_version; |
| 125 | extern int am_root; |
| 126 | |
| 127 | if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) { |
| 128 | rprintf(FERROR,"rsync denied on module %s from %s (%s)\n", |
| 129 | name, client_name(fd), client_addr(fd)); |
| 130 | io_printf(fd,"@ERROR: access denied to %s from %s (%s)\n", |
| 131 | name, client_name(fd), client_addr(fd)); |
| 132 | return -1; |
| 133 | } |
| 134 | |
| 135 | if (!claim_connection(lp_lock_file(), lp_max_connections())) { |
| 136 | if (errno) { |
| 137 | rprintf(FERROR,"failed to open lock file %s : %s\n", |
| 138 | lp_lock_file(), strerror(errno)); |
| 139 | io_printf(fd,"@ERROR: failed to open lock file %s : %s\n", |
| 140 | lp_lock_file(), strerror(errno)); |
| 141 | } else { |
| 142 | rprintf(FERROR,"max connections (%d) reached\n", |
| 143 | lp_max_connections()); |
| 144 | io_printf(fd,"@ERROR: max connections (%d) reached - try again later\n", lp_max_connections()); |
| 145 | } |
| 146 | return -1; |
| 147 | } |
| 148 | |
| 149 | |
| 150 | user = auth_server(fd, i, addr, "@RSYNCD: AUTHREQD "); |
| 151 | |
| 152 | if (!user) { |
| 153 | rprintf(FERROR,"auth failed on module %s from %s (%s)\n", |
| 154 | name, client_name(fd), client_addr(fd)); |
| 155 | io_printf(fd,"@ERROR: auth failed on module %s\n",name); |
| 156 | return -1; |
| 157 | } |
| 158 | |
| 159 | module_id = i; |
| 160 | |
| 161 | if (lp_read_only(i)) |
| 162 | read_only = 1; |
| 163 | |
| 164 | p = lp_uid(i); |
| 165 | if (!name_to_uid(p, &uid)) { |
| 166 | if (!isdigit(*p)) { |
| 167 | rprintf(FERROR,"Invalid uid %s\n", p); |
| 168 | io_printf(fd,"@ERROR: invalid uid\n"); |
| 169 | return -1; |
| 170 | } |
| 171 | uid = atoi(p); |
| 172 | } |
| 173 | |
| 174 | p = lp_gid(i); |
| 175 | if (!name_to_gid(p, &gid)) { |
| 176 | if (!isdigit(*p)) { |
| 177 | rprintf(FERROR,"Invalid gid %s\n", p); |
| 178 | io_printf(fd,"@ERROR: invalid gid\n"); |
| 179 | return -1; |
| 180 | } |
| 181 | gid = atoi(p); |
| 182 | } |
| 183 | |
| 184 | p = lp_exclude_from(i); |
| 185 | add_exclude_file(p, 1, 0); |
| 186 | |
| 187 | p = lp_exclude(i); |
| 188 | add_exclude_line(p); |
| 189 | |
| 190 | log_open(); |
| 191 | |
| 192 | if (chroot(lp_path(i))) { |
| 193 | rprintf(FERROR,"chroot %s failed\n", lp_path(i)); |
| 194 | io_printf(fd,"@ERROR: chroot failed\n"); |
| 195 | return -1; |
| 196 | } |
| 197 | |
| 198 | if (chdir("/")) { |
| 199 | rprintf(FERROR,"chdir %s failed\n", lp_path(i)); |
| 200 | io_printf(fd,"@ERROR: chdir failed\n"); |
| 201 | return -1; |
| 202 | } |
| 203 | |
| 204 | if (setgid(gid) || getgid() != gid) { |
| 205 | rprintf(FERROR,"setgid %d failed\n", gid); |
| 206 | io_printf(fd,"@ERROR: setgid failed\n"); |
| 207 | return -1; |
| 208 | } |
| 209 | |
| 210 | if (setuid(uid) || getuid() != uid) { |
| 211 | rprintf(FERROR,"setuid %d failed\n", uid); |
| 212 | io_printf(fd,"@ERROR: setuid failed\n"); |
| 213 | return -1; |
| 214 | } |
| 215 | |
| 216 | am_root = (getuid() == 0); |
| 217 | |
| 218 | io_printf(fd,"@RSYNCD: OK\n"); |
| 219 | |
| 220 | argv[argc++] = "rsyncd"; |
| 221 | |
| 222 | while (1) { |
| 223 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 224 | return -1; |
| 225 | } |
| 226 | |
| 227 | if (!*line) break; |
| 228 | |
| 229 | p = line; |
| 230 | |
| 231 | argv[argc] = strdup(p); |
| 232 | if (!argv[argc]) { |
| 233 | return -1; |
| 234 | } |
| 235 | |
| 236 | if (start_glob) { |
| 237 | if (start_glob == 1) { |
| 238 | request = strdup(p); |
| 239 | start_glob++; |
| 240 | } |
| 241 | glob_expand(name, argv, &argc, MAX_ARGS); |
| 242 | } else { |
| 243 | argc++; |
| 244 | } |
| 245 | |
| 246 | if (strcmp(line,".") == 0) { |
| 247 | start_glob = 1; |
| 248 | } |
| 249 | |
| 250 | if (argc == MAX_ARGS) { |
| 251 | return -1; |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | ret = parse_arguments(argc, argv); |
| 256 | |
| 257 | if (request) { |
| 258 | if (*user) { |
| 259 | rprintf(FINFO,"rsync %s %s from %s@%s (%s)\n", |
| 260 | am_sender?"on":"to", |
| 261 | request, user, host, addr); |
| 262 | } else { |
| 263 | rprintf(FINFO,"rsync %s %s from %s (%s)\n", |
| 264 | am_sender?"on":"to", |
| 265 | request, host, addr); |
| 266 | } |
| 267 | free(request); |
| 268 | } |
| 269 | |
| 270 | #if !TRIDGE |
| 271 | /* don't allow the logs to be flooded too fast */ |
| 272 | if (verbose > 1) verbose = 1; |
| 273 | #endif |
| 274 | |
| 275 | argc -= optind; |
| 276 | argp = argv + optind; |
| 277 | optind = 0; |
| 278 | |
| 279 | if (remote_version > 17 && am_sender) |
| 280 | io_start_multiplex_out(fd); |
| 281 | |
| 282 | if (!ret) { |
| 283 | rprintf(FERROR,"Error parsing options (unsupported option?) - aborting\n"); |
| 284 | exit_cleanup(1); |
| 285 | } |
| 286 | |
| 287 | start_server(fd, fd, argc, argp); |
| 288 | |
| 289 | return 0; |
| 290 | } |
| 291 | |
| 292 | /* send a list of available modules to the client. Don't list those |
| 293 | with "list = False". */ |
| 294 | static void send_listing(int fd) |
| 295 | { |
| 296 | int n = lp_numservices(); |
| 297 | int i; |
| 298 | |
| 299 | for (i=0;i<n;i++) |
| 300 | if (lp_list(i)) |
| 301 | io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i)); |
| 302 | } |
| 303 | |
| 304 | /* this is called when a socket connection is established to a client |
| 305 | and we want to start talking. The setup of the system is done from |
| 306 | here */ |
| 307 | static int start_daemon(int fd) |
| 308 | { |
| 309 | char line[200]; |
| 310 | char *motd; |
| 311 | int i = -1; |
| 312 | extern char *config_file; |
| 313 | extern int remote_version; |
| 314 | |
| 315 | if (!lp_load(config_file, 0)) { |
| 316 | exit_cleanup(1); |
| 317 | } |
| 318 | |
| 319 | set_socket_options(fd,"SO_KEEPALIVE"); |
| 320 | set_socket_options(fd,lp_socket_options()); |
| 321 | |
| 322 | |
| 323 | io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION); |
| 324 | |
| 325 | motd = lp_motd_file(); |
| 326 | if (*motd) { |
| 327 | FILE *f = fopen(motd,"r"); |
| 328 | while (f && !feof(f)) { |
| 329 | int len = fread(line, 1, sizeof(line)-1, f); |
| 330 | if (len > 0) { |
| 331 | line[len] = 0; |
| 332 | io_printf(fd,"%s", line); |
| 333 | } |
| 334 | } |
| 335 | if (f) fclose(f); |
| 336 | io_printf(fd,"\n"); |
| 337 | } |
| 338 | |
| 339 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 340 | return -1; |
| 341 | } |
| 342 | |
| 343 | if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) { |
| 344 | io_printf(fd,"@ERROR: protocol startup error\n"); |
| 345 | return -1; |
| 346 | } |
| 347 | |
| 348 | while (i == -1) { |
| 349 | line[0] = 0; |
| 350 | if (!read_line(fd, line, sizeof(line)-1)) { |
| 351 | return -1; |
| 352 | } |
| 353 | |
| 354 | if (!*line || strcmp(line,"#list")==0) { |
| 355 | send_listing(fd); |
| 356 | return -1; |
| 357 | } |
| 358 | |
| 359 | if (*line == '#') { |
| 360 | /* it's some sort of command that I don't understand */ |
| 361 | io_printf(fd,"@ERROR: Unknown command '%s'\n", line); |
| 362 | return -1; |
| 363 | } |
| 364 | |
| 365 | i = lp_number(line); |
| 366 | if (i == -1) { |
| 367 | io_printf(fd,"@ERROR: Unknown module '%s'\n", line); |
| 368 | return -1; |
| 369 | } |
| 370 | } |
| 371 | |
| 372 | return rsync_module(fd, i); |
| 373 | } |
| 374 | |
| 375 | |
| 376 | int daemon_main(void) |
| 377 | { |
| 378 | extern char *config_file; |
| 379 | |
| 380 | /* this ensures that we don't call getcwd after the chroot, |
| 381 | which doesn't work on platforms that use popen("pwd","r") |
| 382 | for getcwd */ |
| 383 | push_dir("/", 0); |
| 384 | |
| 385 | if (is_a_socket(STDIN_FILENO)) { |
| 386 | int i; |
| 387 | |
| 388 | /* we are running via inetd - close off stdout and |
| 389 | stderr so that library functions (and getopt) don't |
| 390 | try to use them. Redirect them to /dev/null */ |
| 391 | for (i=1;i<3;i++) { |
| 392 | close(i); |
| 393 | open("/dev/null", O_RDWR); |
| 394 | } |
| 395 | return start_daemon(STDIN_FILENO); |
| 396 | } |
| 397 | |
| 398 | become_daemon(); |
| 399 | |
| 400 | if (!lp_load(config_file, 1)) { |
| 401 | fprintf(stderr,"failed to load config file %s\n", config_file); |
| 402 | exit_cleanup(1); |
| 403 | } |
| 404 | |
| 405 | log_open(); |
| 406 | |
| 407 | rprintf(FINFO,"rsyncd version %s starting\n",VERSION); |
| 408 | |
| 409 | start_accept_loop(rsync_port, start_daemon); |
| 410 | return -1; |
| 411 | } |
| 412 | |