1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Berkeley Software Design Inc's name may not be used to endorse or 15 * promote products derived from this software without specific prior 16 * written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * from BSDI kern.c,v 1.2 1998/11/25 22:38:27 don Exp 31 */ 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <sys/param.h> 37 #include <sys/mount.h> 38 #include <sys/queue.h> 39 #include <sys/socket.h> 40 #include <sys/stat.h> 41 42 #include <netinet/in.h> 43 #include <arpa/inet.h> 44 45 #include <err.h> 46 #include <errno.h> 47 #include <fcntl.h> 48 #include <paths.h> 49 #include <pwd.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <syslog.h> 54 #include <unistd.h> 55 #include <netdb.h> 56 57 #include "nlm_prot.h" 58 #include <nfs/nfsproto.h> 59 #include <nfs/nfs_lock.h> 60 61 #include "lockd.h" 62 #include "lockd_lock.h" 63 #include <nfsclient/nfs.h> 64 65 #define DAEMON_USERNAME "daemon" 66 67 /* Lock request owner. */ 68 typedef struct __owner { 69 pid_t pid; /* Process ID. */ 70 time_t tod; /* Time-of-day. */ 71 } OWNER; 72 static OWNER owner; 73 74 static char hostname[MAXHOSTNAMELEN + 1]; /* Hostname. */ 75 static int devfd; 76 77 static void client_cleanup(void); 78 static const char *from_addr(struct sockaddr *); 79 int lock_request(LOCKD_MSG *); 80 static void set_auth(CLIENT *cl, struct xucred *ucred); 81 void show(LOCKD_MSG *); 82 int test_request(LOCKD_MSG *); 83 int unlock_request(LOCKD_MSG *); 84 85 static int 86 nfslockdans(int vers, struct lockd_ans *ansp) 87 { 88 89 ansp->la_vers = vers; 90 return (write(devfd, ansp, sizeof *ansp) <= 0); 91 } 92 93 /* 94 * will break because fifo needs to be repopened when EOF'd 95 */ 96 #define lockd_seteuid(uid) seteuid(uid) 97 98 #define d_calls (debug_level > 1) 99 #define d_args (debug_level > 2) 100 101 static const char * 102 from_addr(struct sockaddr *saddr) 103 { 104 static char inet_buf[INET6_ADDRSTRLEN]; 105 106 if (getnameinfo(saddr, saddr->sa_len, inet_buf, sizeof(inet_buf), 107 NULL, 0, NI_NUMERICHOST) == 0) 108 return inet_buf; 109 return "???"; 110 } 111 112 void 113 client_cleanup(void) 114 { 115 (void)lockd_seteuid(0); 116 exit(-1); 117 } 118 119 /* 120 * client_request -- 121 * Loop around messages from the kernel, forwarding them off to 122 * NLM servers. 123 */ 124 pid_t 125 client_request(void) 126 { 127 LOCKD_MSG msg; 128 int nr, ret; 129 pid_t child; 130 uid_t daemon_uid; 131 struct passwd *pw; 132 133 /* Open the dev . */ 134 devfd = open(_PATH_DEV _PATH_NFSLCKDEV, O_RDWR | O_NONBLOCK); 135 if (devfd < 0) { 136 syslog(LOG_ERR, "open: %s: %m", _PATH_NFSLCKDEV); 137 goto err; 138 } 139 140 signal(SIGPIPE, SIG_IGN); 141 142 /* 143 * Create a separate process, the client code is really a separate 144 * daemon that shares a lot of code. 145 */ 146 switch (child = fork()) { 147 case -1: 148 err(1, "fork"); 149 case 0: 150 setproctitle("client"); 151 break; 152 default: 153 setproctitle("server"); 154 return (child); 155 } 156 157 signal(SIGHUP, (sig_t)client_cleanup); 158 signal(SIGTERM, (sig_t)client_cleanup); 159 160 /* Setup. */ 161 (void)time(&owner.tod); 162 owner.pid = getpid(); 163 (void)gethostname(hostname, sizeof(hostname) - 1); 164 165 pw = getpwnam(DAEMON_USERNAME); 166 if (pw == NULL) { 167 syslog(LOG_ERR, "getpwnam: %s: %m", DAEMON_USERNAME); 168 goto err; 169 } 170 daemon_uid = pw->pw_uid; 171 /* drop our root privileges */ 172 (void)lockd_seteuid(daemon_uid); 173 174 for (;;) { 175 /* Read the fixed length message. */ 176 if ((nr = read(devfd, &msg, sizeof(msg))) == sizeof(msg)) { 177 if (d_args) 178 show(&msg); 179 180 if (msg.lm_version != LOCKD_MSG_VERSION) { 181 syslog(LOG_ERR, 182 "unknown msg type: %d", msg.lm_version); 183 } 184 /* 185 * Send it to the NLM server and don't grant the lock 186 * if we fail for any reason. 187 */ 188 switch (msg.lm_fl.l_type) { 189 case F_RDLCK: 190 case F_WRLCK: 191 if (msg.lm_getlk) 192 ret = test_request(&msg); 193 else 194 ret = lock_request(&msg); 195 break; 196 case F_UNLCK: 197 ret = unlock_request(&msg); 198 break; 199 default: 200 ret = 1; 201 syslog(LOG_ERR, 202 "unknown lock type: %d", msg.lm_fl.l_type); 203 break; 204 } 205 if (ret) { 206 struct lockd_ans ans; 207 208 ans.la_msg_ident = msg.lm_msg_ident; 209 ans.la_errno = EHOSTUNREACH; 210 211 if (nfslockdans(LOCKD_ANS_VERSION, &ans)) { 212 syslog((errno == EPIPE ? LOG_INFO : 213 LOG_ERR), "process %lu: %m", 214 (u_long)msg.lm_msg_ident.pid); 215 } 216 } 217 } else if (nr == -1) { 218 if (errno != EAGAIN) { 219 syslog(LOG_ERR, "read: %s: %m", _PATH_NFSLCKDEV); 220 goto err; 221 } 222 } else if (nr != 0) { 223 syslog(LOG_ERR, 224 "%s: discard %d bytes", _PATH_NFSLCKDEV, nr); 225 } 226 } 227 228 /* Reached only on error. */ 229 err: 230 (void)lockd_seteuid(0); 231 _exit (1); 232 } 233 234 void 235 set_auth(CLIENT *cl, struct xucred *xucred) 236 { 237 int ngroups; 238 239 ngroups = xucred->cr_ngroups - 1; 240 if (ngroups > NGRPS) 241 ngroups = NGRPS; 242 if (cl->cl_auth != NULL) 243 cl->cl_auth->ah_ops->ah_destroy(cl->cl_auth); 244 cl->cl_auth = authunix_create(hostname, 245 xucred->cr_uid, 246 xucred->cr_groups[0], 247 ngroups, 248 &xucred->cr_groups[1]); 249 } 250 251 252 /* 253 * test_request -- 254 * Convert a lock LOCKD_MSG into an NLM request, and send it off. 255 */ 256 int 257 test_request(LOCKD_MSG *msg) 258 { 259 CLIENT *cli; 260 struct timeval timeout = {0, 0}; /* No timeout, no response. */ 261 char dummy; 262 263 if (d_calls) 264 syslog(LOG_DEBUG, "test request: %s: %s to %s", 265 msg->lm_nfsv3 ? "V4" : "V1/3", 266 msg->lm_fl.l_type == F_WRLCK ? "write" : "read", 267 from_addr((struct sockaddr *)&msg->lm_addr)); 268 269 if (msg->lm_nfsv3) { 270 struct nlm4_testargs arg4; 271 272 arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; 273 arg4.cookie.n_len = sizeof(msg->lm_msg_ident); 274 arg4.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 275 arg4.alock.caller_name = hostname; 276 arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; 277 arg4.alock.fh.n_len = msg->lm_fh_len; 278 arg4.alock.oh.n_bytes = (char *)&owner; 279 arg4.alock.oh.n_len = sizeof(owner); 280 arg4.alock.svid = msg->lm_msg_ident.pid; 281 arg4.alock.l_offset = msg->lm_fl.l_start; 282 arg4.alock.l_len = msg->lm_fl.l_len; 283 284 if ((cli = get_client( 285 (struct sockaddr *)&msg->lm_addr, 286 NLM_VERS4)) == NULL) 287 return (1); 288 289 set_auth(cli, &msg->lm_cred); 290 (void)clnt_call(cli, NLM_TEST_MSG, 291 (xdrproc_t)xdr_nlm4_testargs, &arg4, 292 (xdrproc_t)xdr_void, &dummy, timeout); 293 } else { 294 struct nlm_testargs arg; 295 296 arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; 297 arg.cookie.n_len = sizeof(msg->lm_msg_ident); 298 arg.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 299 arg.alock.caller_name = hostname; 300 arg.alock.fh.n_bytes = (char *)&msg->lm_fh; 301 arg.alock.fh.n_len = msg->lm_fh_len; 302 arg.alock.oh.n_bytes = (char *)&owner; 303 arg.alock.oh.n_len = sizeof(owner); 304 arg.alock.svid = msg->lm_msg_ident.pid; 305 arg.alock.l_offset = msg->lm_fl.l_start; 306 arg.alock.l_len = msg->lm_fl.l_len; 307 308 if ((cli = get_client( 309 (struct sockaddr *)&msg->lm_addr, 310 NLM_VERS)) == NULL) 311 return (1); 312 313 set_auth(cli, &msg->lm_cred); 314 (void)clnt_call(cli, NLM_TEST_MSG, 315 (xdrproc_t)xdr_nlm_testargs, &arg, 316 (xdrproc_t)xdr_void, &dummy, timeout); 317 } 318 return (0); 319 } 320 321 /* 322 * lock_request -- 323 * Convert a lock LOCKD_MSG into an NLM request, and send it off. 324 */ 325 int 326 lock_request(LOCKD_MSG *msg) 327 { 328 CLIENT *cli; 329 struct nlm4_lockargs arg4; 330 struct nlm_lockargs arg; 331 struct timeval timeout = {0, 0}; /* No timeout, no response. */ 332 char dummy; 333 334 if (d_calls) 335 syslog(LOG_DEBUG, "lock request: %s: %s to %s", 336 msg->lm_nfsv3 ? "V4" : "V1/3", 337 msg->lm_fl.l_type == F_WRLCK ? "write" : "read", 338 from_addr((struct sockaddr *)&msg->lm_addr)); 339 340 if (msg->lm_nfsv3) { 341 arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; 342 arg4.cookie.n_len = sizeof(msg->lm_msg_ident); 343 arg4.block = msg->lm_wait ? 1 : 0; 344 arg4.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 345 arg4.alock.caller_name = hostname; 346 arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; 347 arg4.alock.fh.n_len = msg->lm_fh_len; 348 arg4.alock.oh.n_bytes = (char *)&owner; 349 arg4.alock.oh.n_len = sizeof(owner); 350 arg4.alock.svid = msg->lm_msg_ident.pid; 351 arg4.alock.l_offset = msg->lm_fl.l_start; 352 arg4.alock.l_len = msg->lm_fl.l_len; 353 arg4.reclaim = 0; 354 arg4.state = nsm_state; 355 356 if ((cli = get_client( 357 (struct sockaddr *)&msg->lm_addr, 358 NLM_VERS4)) == NULL) 359 return (1); 360 361 set_auth(cli, &msg->lm_cred); 362 (void)clnt_call(cli, NLM_LOCK_MSG, 363 (xdrproc_t)xdr_nlm4_lockargs, &arg4, 364 (xdrproc_t)xdr_void, &dummy, timeout); 365 } else { 366 arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; 367 arg.cookie.n_len = sizeof(msg->lm_msg_ident); 368 arg.block = msg->lm_wait ? 1 : 0; 369 arg.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 370 arg.alock.caller_name = hostname; 371 arg.alock.fh.n_bytes = (char *)&msg->lm_fh; 372 arg.alock.fh.n_len = msg->lm_fh_len; 373 arg.alock.oh.n_bytes = (char *)&owner; 374 arg.alock.oh.n_len = sizeof(owner); 375 arg.alock.svid = msg->lm_msg_ident.pid; 376 arg.alock.l_offset = msg->lm_fl.l_start; 377 arg.alock.l_len = msg->lm_fl.l_len; 378 arg.reclaim = 0; 379 arg.state = nsm_state; 380 381 if ((cli = get_client( 382 (struct sockaddr *)&msg->lm_addr, 383 NLM_VERS)) == NULL) 384 return (1); 385 386 set_auth(cli, &msg->lm_cred); 387 (void)clnt_call(cli, NLM_LOCK_MSG, 388 (xdrproc_t)xdr_nlm_lockargs, &arg, 389 (xdrproc_t)xdr_void, &dummy, timeout); 390 } 391 return (0); 392 } 393 394 /* 395 * unlock_request -- 396 * Convert an unlock LOCKD_MSG into an NLM request, and send it off. 397 */ 398 int 399 unlock_request(LOCKD_MSG *msg) 400 { 401 CLIENT *cli; 402 struct nlm4_unlockargs arg4; 403 struct nlm_unlockargs arg; 404 struct timeval timeout = {0, 0}; /* No timeout, no response. */ 405 char dummy; 406 407 if (d_calls) 408 syslog(LOG_DEBUG, "unlock request: %s: to %s", 409 msg->lm_nfsv3 ? "V4" : "V1/3", 410 from_addr((struct sockaddr *)&msg->lm_addr)); 411 412 if (msg->lm_nfsv3) { 413 arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; 414 arg4.cookie.n_len = sizeof(msg->lm_msg_ident); 415 arg4.alock.caller_name = hostname; 416 arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; 417 arg4.alock.fh.n_len = msg->lm_fh_len; 418 arg4.alock.oh.n_bytes = (char *)&owner; 419 arg4.alock.oh.n_len = sizeof(owner); 420 arg4.alock.svid = msg->lm_msg_ident.pid; 421 arg4.alock.l_offset = msg->lm_fl.l_start; 422 arg4.alock.l_len = msg->lm_fl.l_len; 423 424 if ((cli = get_client( 425 (struct sockaddr *)&msg->lm_addr, 426 NLM_VERS4)) == NULL) 427 return (1); 428 429 set_auth(cli, &msg->lm_cred); 430 (void)clnt_call(cli, NLM_UNLOCK_MSG, 431 (xdrproc_t)xdr_nlm4_unlockargs, &arg4, 432 (xdrproc_t)xdr_void, &dummy, timeout); 433 } else { 434 arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; 435 arg.cookie.n_len = sizeof(msg->lm_msg_ident); 436 arg.alock.caller_name = hostname; 437 arg.alock.fh.n_bytes = (char *)&msg->lm_fh; 438 arg.alock.fh.n_len = msg->lm_fh_len; 439 arg.alock.oh.n_bytes = (char *)&owner; 440 arg.alock.oh.n_len = sizeof(owner); 441 arg.alock.svid = msg->lm_msg_ident.pid; 442 arg.alock.l_offset = msg->lm_fl.l_start; 443 arg.alock.l_len = msg->lm_fl.l_len; 444 445 if ((cli = get_client( 446 (struct sockaddr *)&msg->lm_addr, 447 NLM_VERS)) == NULL) 448 return (1); 449 450 set_auth(cli, &msg->lm_cred); 451 (void)clnt_call(cli, NLM_UNLOCK_MSG, 452 (xdrproc_t)xdr_nlm_unlockargs, &arg, 453 (xdrproc_t)xdr_void, &dummy, timeout); 454 } 455 456 return (0); 457 } 458 459 int 460 lock_answer(int pid, netobj *netcookie, int result, int *pid_p, int version) 461 { 462 struct lockd_ans ans; 463 464 if (netcookie->n_len != sizeof(ans.la_msg_ident)) { 465 if (pid == -1) { /* we're screwed */ 466 syslog(LOG_ERR, "inedible nlm cookie"); 467 return -1; 468 } 469 ans.la_msg_ident.pid = pid; 470 ans.la_msg_ident.msg_seq = -1; 471 } else { 472 memcpy(&ans.la_msg_ident, netcookie->n_bytes, 473 sizeof(ans.la_msg_ident)); 474 } 475 476 if (d_calls) 477 syslog(LOG_DEBUG, "lock answer: pid %lu: %s %d", 478 (unsigned long)ans.la_msg_ident.pid, 479 version == NLM_VERS4 ? "nlmv4" : "nlmv3", 480 result); 481 482 ans.la_set_getlk_pid = 0; 483 if (version == NLM_VERS4) 484 switch (result) { 485 case nlm4_granted: 486 ans.la_errno = 0; 487 break; 488 default: 489 ans.la_errno = EACCES; 490 break; 491 case nlm4_denied: 492 if (pid_p == NULL) 493 ans.la_errno = EAGAIN; 494 else { 495 /* this is an answer to a nlm_test msg */ 496 ans.la_set_getlk_pid = 1; 497 ans.la_getlk_pid = *pid_p; 498 ans.la_errno = 0; 499 } 500 break; 501 case nlm4_denied_nolocks: 502 ans.la_errno = EAGAIN; 503 break; 504 case nlm4_blocked: 505 return -1; 506 /* NOTREACHED */ 507 case nlm4_denied_grace_period: 508 ans.la_errno = EAGAIN; 509 break; 510 case nlm4_deadlck: 511 ans.la_errno = EDEADLK; 512 break; 513 case nlm4_rofs: 514 ans.la_errno = EROFS; 515 break; 516 case nlm4_stale_fh: 517 ans.la_errno = ESTALE; 518 break; 519 case nlm4_fbig: 520 ans.la_errno = EFBIG; 521 break; 522 case nlm4_failed: 523 ans.la_errno = EACCES; 524 break; 525 } 526 else 527 switch (result) { 528 case nlm_granted: 529 ans.la_errno = 0; 530 break; 531 default: 532 ans.la_errno = EACCES; 533 break; 534 case nlm_denied: 535 if (pid_p == NULL) 536 ans.la_errno = EAGAIN; 537 else { 538 /* this is an answer to a nlm_test msg */ 539 ans.la_set_getlk_pid = 1; 540 ans.la_getlk_pid = *pid_p; 541 ans.la_errno = 0; 542 } 543 break; 544 case nlm_denied_nolocks: 545 ans.la_errno = EAGAIN; 546 break; 547 case nlm_blocked: 548 return -1; 549 /* NOTREACHED */ 550 case nlm_denied_grace_period: 551 ans.la_errno = EAGAIN; 552 break; 553 case nlm_deadlck: 554 ans.la_errno = EDEADLK; 555 break; 556 } 557 558 if (nfslockdans(LOCKD_ANS_VERSION, &ans)) { 559 syslog(((errno == EPIPE || errno == ESRCH) ? 560 LOG_INFO : LOG_ERR), 561 "process %lu: %m", (u_long)ans.la_msg_ident.pid); 562 return -1; 563 } 564 return 0; 565 } 566 567 /* 568 * show -- 569 * Display the contents of a kernel LOCKD_MSG structure. 570 */ 571 void 572 show(LOCKD_MSG *mp) 573 { 574 static char hex[] = "0123456789abcdef"; 575 struct fid *fidp; 576 fsid_t *fsidp; 577 size_t len; 578 u_int8_t *p, *t, buf[NFS_SMALLFH*3+1]; 579 580 syslog(LOG_DEBUG, "process ID: %lu\n", (long)mp->lm_msg_ident.pid); 581 582 fsidp = (fsid_t *)&mp->lm_fh; 583 fidp = (struct fid *)((u_int8_t *)&mp->lm_fh + sizeof(fsid_t)); 584 585 for (t = buf, p = (u_int8_t *)mp->lm_fh, 586 len = mp->lm_fh_len; 587 len > 0; ++p, --len) { 588 *t++ = '\\'; 589 *t++ = hex[(*p & 0xf0) >> 4]; 590 *t++ = hex[*p & 0x0f]; 591 } 592 *t = '\0'; 593 594 syslog(LOG_DEBUG, "fh_len %d, fh %s\n", (int)mp->lm_fh_len, buf); 595 596 /* Show flock structure. */ 597 syslog(LOG_DEBUG, "start %llu; len %llu; pid %lu; type %d; whence %d\n", 598 (unsigned long long)mp->lm_fl.l_start, 599 (unsigned long long)mp->lm_fl.l_len, (u_long)mp->lm_fl.l_pid, 600 mp->lm_fl.l_type, mp->lm_fl.l_whence); 601 602 /* Show wait flag. */ 603 syslog(LOG_DEBUG, "wait was %s\n", mp->lm_wait ? "set" : "not set"); 604 } 605