nfsd.c revision 1.64
1 /* $NetBSD: nfsd.c,v 1.64 2015/09/12 13:50:55 joerg Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #ifndef lint 37 __COPYRIGHT("@(#) Copyright (c) 1989, 1993, 1994\ 38 The Regents of the University of California. All rights reserved."); 39 #endif /* not lint */ 40 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)nfsd.c 8.9 (Berkeley) 3/29/95"; 44 #else 45 __RCSID("$NetBSD: nfsd.c,v 1.64 2015/09/12 13:50:55 joerg Exp $"); 46 #endif 47 #endif /* not lint */ 48 49 #include <sys/param.h> 50 #include <sys/ioctl.h> 51 #include <sys/stat.h> 52 #include <sys/wait.h> 53 #include <sys/uio.h> 54 #include <sys/ucred.h> 55 #include <sys/mount.h> 56 #include <sys/socket.h> 57 #include <sys/socketvar.h> 58 #include <poll.h> 59 60 #include <rpc/rpc.h> 61 #include <rpc/pmap_clnt.h> 62 #include <rpc/pmap_prot.h> 63 64 #include <nfs/rpcv2.h> 65 #include <nfs/nfsproto.h> 66 #include <nfs/nfs.h> 67 68 #include <err.h> 69 #include <errno.h> 70 #include <fcntl.h> 71 #include <grp.h> 72 #include <paths.h> 73 #include <pwd.h> 74 #include <pthread.h> 75 #include <signal.h> 76 #include <stdio.h> 77 #include <stdlib.h> 78 #include <string.h> 79 #include <syslog.h> 80 #include <unistd.h> 81 #include <netdb.h> 82 83 /* Global defs */ 84 #ifdef DEBUG 85 #define syslog(e, s, args...) \ 86 do { \ 87 fprintf(stderr,(s), ## args); \ 88 fprintf(stderr, "\n"); \ 89 } while (/*CONSTCOND*/0) 90 static int debug = 1; 91 #else 92 static int debug = 0; 93 #endif 94 95 static void nonfs(int); 96 __dead static void usage(void); 97 98 static void * 99 worker(void *dummy) 100 { 101 struct nfsd_srvargs nsd; 102 int nfssvc_flag; 103 104 pthread_setname_np(pthread_self(), "slave", NULL); 105 nfssvc_flag = NFSSVC_NFSD; 106 memset(&nsd, 0, sizeof(nsd)); 107 while (nfssvc(nfssvc_flag, &nsd) < 0) { 108 if (errno != ENEEDAUTH) { 109 syslog(LOG_ERR, "nfssvc: %m"); 110 exit(1); 111 } 112 nfssvc_flag = NFSSVC_NFSD | NFSSVC_AUTHINFAIL; 113 } 114 115 return NULL; 116 } 117 118 struct conf { 119 struct addrinfo *ai; 120 struct netconfig *nc; 121 struct netbuf nb; 122 struct pollfd pfd; 123 }; 124 125 #define NFS_UDP4 0 126 #define NFS_TCP4 1 127 #define NFS_UDP6 2 128 #define NFS_TCP6 3 129 130 static int cfg_family[] = { PF_INET, PF_INET, PF_INET6, PF_INET6 }; 131 static const char *cfg_netconf[] = { "udp", "tcp", "udp6", "tcp6" }; 132 static int cfg_socktype[] = { 133 SOCK_DGRAM, SOCK_STREAM, SOCK_DGRAM, SOCK_STREAM }; 134 static int cfg_protocol[] = { 135 IPPROTO_UDP, IPPROTO_TCP, IPPROTO_UDP, IPPROTO_TCP }; 136 137 static int 138 tryconf(struct conf *cfg, int t, int reregister) 139 { 140 struct addrinfo hints; 141 int ecode; 142 143 memset(&hints, 0, sizeof hints); 144 hints.ai_flags = AI_PASSIVE; 145 hints.ai_family = cfg_family[t]; 146 hints.ai_socktype = cfg_socktype[t]; 147 hints.ai_protocol = cfg_protocol[t]; 148 149 ecode = getaddrinfo(NULL, "nfs", &hints, &cfg->ai); 150 if (ecode != 0) { 151 syslog(LOG_ERR, "getaddrinfo %s: %s", cfg_netconf[t], 152 gai_strerror(ecode)); 153 return -1; 154 } 155 156 cfg->nc = getnetconfigent(cfg_netconf[t]); 157 158 if (cfg->nc == NULL) { 159 syslog(LOG_ERR, "getnetconfigent %s failed: %m", 160 cfg_netconf[t]); 161 goto out; 162 } 163 164 cfg->nb.buf = cfg->ai->ai_addr; 165 cfg->nb.len = cfg->nb.maxlen = cfg->ai->ai_addrlen; 166 if (reregister) 167 if (!rpcb_set(RPCPROG_NFS, 2, cfg->nc, &cfg->nb)) { 168 syslog(LOG_ERR, "rpcb_set %s failed", cfg_netconf[t]); 169 goto out1; 170 } 171 return 0; 172 out1: 173 freenetconfigent(cfg->nc); 174 cfg->nc = NULL; 175 out: 176 freeaddrinfo(cfg->ai); 177 cfg->ai = NULL; 178 return -1; 179 } 180 181 static int 182 setupsock(struct conf *cfg, struct pollfd *set, int p) 183 { 184 int sock; 185 struct nfsd_args nfsdargs; 186 struct addrinfo *ai = cfg->ai; 187 int on = 1; 188 189 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); 190 191 if (sock == -1) { 192 syslog(LOG_ERR, "can't create %s socket: %m", cfg_netconf[p]); 193 return -1; 194 } 195 if (cfg_family[p] == PF_INET6) { 196 if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, 197 sizeof(on)) == -1) { 198 syslog(LOG_ERR, "can't set v6-only binding for %s " 199 "socket: %m", cfg_netconf[p]); 200 goto out; 201 } 202 } 203 204 if (cfg_protocol[p] == IPPROTO_TCP) { 205 if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, 206 sizeof(on)) == -1) { 207 syslog(LOG_ERR, "setsockopt SO_REUSEADDR for %s: %m", 208 cfg_netconf[p]); 209 goto out; 210 } 211 } 212 213 if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) { 214 syslog(LOG_ERR, "can't bind %s addr: %m", cfg_netconf[p]); 215 goto out; 216 } 217 218 if (cfg_protocol[p] == IPPROTO_TCP) { 219 if (listen(sock, 5) == -1) { 220 syslog(LOG_ERR, "listen failed"); 221 goto out; 222 } 223 } 224 225 if (!rpcb_set(RPCPROG_NFS, 2, cfg->nc, &cfg->nb) || 226 !rpcb_set(RPCPROG_NFS, 3, cfg->nc, &cfg->nb)) { 227 syslog(LOG_ERR, "can't register with %s portmap", 228 cfg_netconf[p]); 229 goto out; 230 } 231 232 233 if (cfg_protocol[p] == IPPROTO_TCP) 234 set->fd = sock; 235 else { 236 nfsdargs.sock = sock; 237 nfsdargs.name = NULL; 238 nfsdargs.namelen = 0; 239 if (nfssvc(NFSSVC_ADDSOCK, &nfsdargs) < 0) { 240 syslog(LOG_ERR, "can't add %s socket", cfg_netconf[p]); 241 goto out; 242 } 243 (void)close(sock); 244 } 245 return 0; 246 out: 247 (void)close(sock); 248 return -1; 249 } 250 251 /* 252 * The functions daemon2_fork() and daemon2_detach() below provide 253 * functionality similar to daemon(3) but split into two phases. 254 * daemon2_fork() is called early, before creating resources that 255 * cannot be inherited across a fork, such as threads or kqueues. 256 * When the daemon is ready to provide service, daemon2_detach() 257 * is called to complete the daemonization and signal the parent 258 * process to exit. 259 * 260 * These functions could potentially be moved to a library and 261 * shared by other daemons. 262 * 263 * The return value from daemon2_fork() is a file descriptor to 264 * be passed as the first argument to daemon2_detach(). 265 */ 266 267 static int 268 daemon2_fork(void) 269 { 270 int i; 271 int fd; 272 int r; 273 pid_t pid; 274 int detach_msg_pipe[2]; 275 276 /* 277 * Set up a pipe for signalling the parent, making sure the 278 * write end does not get allocated one of the file 279 * descriptors that may be closed in daemon2_detach(). The 280 * read end does not need such protection. 281 */ 282 for (i = 0; i < 3; i++) { 283 r = pipe2(detach_msg_pipe, O_CLOEXEC|O_NOSIGPIPE); 284 if (r < 0) 285 return -1; 286 if (detach_msg_pipe[1] <= STDERR_FILENO && 287 (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { 288 (void)dup2(fd, detach_msg_pipe[0]); 289 (void)dup2(fd, detach_msg_pipe[1]); 290 if (fd > STDERR_FILENO) 291 (void)close(fd); 292 continue; 293 } 294 break; 295 } 296 297 pid = fork(); 298 switch (pid) { 299 case -1: 300 return -1; 301 case 0: 302 /* child */ 303 (void)close(detach_msg_pipe[0]); 304 return detach_msg_pipe[1]; 305 default: 306 break; 307 } 308 309 /* Parent */ 310 (void)close(detach_msg_pipe[1]); 311 312 for (;;) { 313 ssize_t nread; 314 char dummy; 315 nread = read(detach_msg_pipe[0], &dummy, 1); 316 if (nread < 0) { 317 if (errno == EINTR) 318 continue; 319 _exit(1); 320 } else if (nread == 0) { 321 _exit(1); 322 } else { /* nread > 0 */ 323 _exit(0); 324 } 325 } 326 } 327 328 static int 329 daemon2_detach(int parentfd, int nochdir, int noclose) 330 { 331 int fd; 332 333 if (setsid() == -1) 334 return -1; 335 336 if (!nochdir) 337 (void)chdir("/"); 338 339 if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { 340 (void)dup2(fd, STDIN_FILENO); 341 (void)dup2(fd, STDOUT_FILENO); 342 (void)dup2(fd, STDERR_FILENO); 343 if (fd > STDERR_FILENO) 344 (void)close(fd); 345 } 346 347 while (1) { 348 ssize_t r = write(parentfd, "", 1); 349 if (r < 0) { 350 if (errno == EINTR) 351 continue; 352 else if (errno == EPIPE) 353 break; 354 else 355 return -1; 356 } else if (r == 0) { 357 /* Should not happen */ 358 return -1; 359 } else { 360 break; 361 } 362 } 363 364 (void)close(parentfd); 365 366 return 0; 367 } 368 369 /* 370 * Nfs server daemon mostly just a user context for nfssvc() 371 * 372 * 1 - do file descriptor and signal cleanup 373 * 2 - create the nfsd thread(s) 374 * 3 - create server socket(s) 375 * 4 - register socket with portmap 376 * 377 * For connectionless protocols, just pass the socket into the kernel via 378 * nfssvc(). 379 * For connection based sockets, loop doing accepts. When you get a new 380 * socket from accept, pass the msgsock into the kernel via nfssvc(). 381 * The arguments are: 382 * -r - reregister with portmapper 383 * -t - support only tcp nfs clients 384 * -u - support only udp nfs clients 385 * -n num how many threads to create. 386 * -4 - use only ipv4 387 * -6 - use only ipv6 388 */ 389 int 390 main(int argc, char *argv[]) 391 { 392 struct conf cfg[4]; 393 struct pollfd set[__arraycount(cfg)]; 394 int ch, connect_type_cnt; 395 size_t i, nfsdcnt; 396 int reregister; 397 int tcpflag, udpflag; 398 int ip6flag, ip4flag; 399 int s, compat; 400 int parent_fd = -1; 401 402 #define DEFNFSDCNT 4 403 nfsdcnt = DEFNFSDCNT; 404 compat = reregister = 0; 405 tcpflag = udpflag = 1; 406 ip6flag = ip4flag = 1; 407 #define GETOPT "46n:rtu" 408 #define USAGE "[-46rtu] [-n num_servers]" 409 while ((ch = getopt(argc, argv, GETOPT)) != -1) { 410 switch (ch) { 411 case '6': 412 ip6flag = 1; 413 ip4flag = 0; 414 s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP); 415 if (s < 0 && (errno == EPROTONOSUPPORT || 416 errno == EPFNOSUPPORT || errno == EAFNOSUPPORT)) 417 ip6flag = 0; 418 else 419 close(s); 420 break; 421 case '4': 422 ip6flag = 0; 423 ip4flag = 1; 424 s = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP); 425 if (s < 0 && (errno == EPROTONOSUPPORT || 426 errno == EPFNOSUPPORT || errno == EAFNOSUPPORT)) 427 ip4flag = 0; 428 else 429 close(s); 430 break; 431 case 'n': 432 nfsdcnt = atoi(optarg); 433 if (nfsdcnt < 1) { 434 warnx("nfsd count %zu; reset to %d", nfsdcnt, 435 DEFNFSDCNT); 436 nfsdcnt = DEFNFSDCNT; 437 } 438 break; 439 case 'r': 440 reregister = 1; 441 break; 442 case 't': 443 compat |= 2; 444 tcpflag = 1; 445 udpflag = 0; 446 break; 447 case 'u': 448 compat |= 1; 449 tcpflag = 0; 450 udpflag = 1; 451 break; 452 default: 453 case '?': 454 usage(); 455 } 456 } 457 argv += optind; 458 argc -= optind; 459 460 if (compat == 3) { 461 warnx("Old -tu options detected; enabling both udp and tcp."); 462 warnx("This is the default behavior now and you can remove"); 463 warnx("all options."); 464 tcpflag = udpflag = 1; 465 if (ip6flag == 1 && ip4flag == 0) 466 ip4flag = 1; 467 } 468 469 if (debug == 0) { 470 parent_fd = daemon2_fork(); 471 } 472 473 openlog("nfsd", LOG_PID, LOG_DAEMON); 474 475 memset(cfg, 0, sizeof(cfg)); 476 for (i = 0; i < __arraycount(cfg); i++) { 477 if (ip4flag == 0 && cfg_family[i] == PF_INET) 478 continue; 479 if (ip6flag == 0 && cfg_family[i] == PF_INET6) 480 continue; 481 if (tcpflag == 0 && cfg_protocol[i] == IPPROTO_TCP) 482 continue; 483 if (udpflag == 0 && cfg_protocol[i] == IPPROTO_UDP) 484 continue; 485 tryconf(&cfg[i], i, reregister); 486 } 487 488 for (i = 0; i < nfsdcnt; i++) { 489 pthread_t t; 490 int error; 491 492 error = pthread_create(&t, NULL, worker, NULL); 493 if (error) { 494 errno = error; 495 syslog(LOG_ERR, "pthread_create: %m"); 496 exit(1); 497 } 498 } 499 500 connect_type_cnt = 0; 501 for (i = 0; i < __arraycount(cfg); i++) { 502 set[i].fd = -1; 503 set[i].events = POLLIN; 504 set[i].revents = 0; 505 506 if (cfg[i].nc == NULL) 507 continue; 508 509 setupsock(&cfg[i], &set[i], i); 510 if (set[i].fd != -1) 511 connect_type_cnt++; 512 513 } 514 515 if (connect_type_cnt == 0) 516 exit(0); 517 518 pthread_setname_np(pthread_self(), "master", NULL); 519 520 if (debug == 0) { 521 daemon2_detach(parent_fd, 0, 0); 522 (void)signal(SIGHUP, SIG_IGN); 523 (void)signal(SIGINT, SIG_IGN); 524 (void)signal(SIGQUIT, SIG_IGN); 525 (void)signal(SIGSYS, nonfs); 526 } 527 528 /* 529 * Loop forever accepting connections and passing the sockets 530 * into the kernel for the mounts. 531 */ 532 for (;;) { 533 if (poll(set, __arraycount(set), INFTIM) == -1) { 534 syslog(LOG_ERR, "poll failed: %m"); 535 exit(1); 536 } 537 538 for (i = 0; i < __arraycount(set); i++) { 539 struct nfsd_args nfsdargs; 540 struct sockaddr_storage ss; 541 socklen_t len; 542 int msgsock; 543 int on = 1; 544 545 if ((set[i].revents & POLLIN) == 0) 546 continue; 547 len = sizeof(ss); 548 if ((msgsock = accept(set[i].fd, 549 (struct sockaddr *)&ss, &len)) == -1) { 550 int serrno = errno; 551 syslog(LOG_ERR, "accept failed: %m"); 552 if (serrno == EINTR || serrno == ECONNABORTED) 553 continue; 554 exit(1); 555 } 556 if (setsockopt(msgsock, SOL_SOCKET, SO_KEEPALIVE, &on, 557 sizeof(on)) == -1) 558 syslog(LOG_ERR, "setsockopt SO_KEEPALIVE: %m"); 559 nfsdargs.sock = msgsock; 560 nfsdargs.name = (void *)&ss; 561 nfsdargs.namelen = len; 562 nfssvc(NFSSVC_ADDSOCK, &nfsdargs); 563 (void)close(msgsock); 564 } 565 } 566 } 567 568 static void 569 usage(void) 570 { 571 (void)fprintf(stderr, "Usage: %s %s\n", getprogname(), USAGE); 572 exit(1); 573 } 574 575 static void 576 nonfs(int signo) 577 { 578 syslog(LOG_ERR, "missing system call: NFS not available."); 579 } 580
Indexes created Wed Oct 15 03:09:54 GMT 2025