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