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/rpcv2.h> 57 #include <nfs/nfsproto.h> 58 #include <nfsclient/nfs_lock.h> 59 60 #include "lockd.h" 61 #include "lockd_lock.h" 62 #include <nfsclient/nfs.h> 63 64 #define DAEMON_USERNAME "daemon" 65 66 /* Lock request owner. */ 67 typedef struct __owner { 68 pid_t pid; /* Process ID. */ 69 time_t tod; /* Time-of-day. */ 70 } OWNER; 71 static OWNER owner; 72 73 static char hostname[MAXHOSTNAMELEN + 1]; /* Hostname. */ 74 static int devfd; 75 76 static void client_cleanup(void); 77 static const char *from_addr(struct sockaddr *); 78 int lock_request(LOCKD_MSG *); 79 static void set_auth(CLIENT *cl, struct xucred *ucred); 80 void show(LOCKD_MSG *); 81 int test_request(LOCKD_MSG *); 82 int unlock_request(LOCKD_MSG *); 83 84 static int 85 nfslockdans(int vers, struct lockd_ans *ansp) 86 { 87 88 ansp->la_vers = vers; 89 return (write(devfd, ansp, sizeof *ansp) <= 0); 90 } 91 92 /* 93 * will break because fifo needs to be repopened when EOF'd 94 */ 95 #define lockd_seteuid(uid) seteuid(uid) 96 97 #define d_calls (debug_level > 1) 98 #define d_args (debug_level > 2) 99 100 static const char * 101 from_addr(saddr) 102 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 priviledges */ 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(cl, xucred) 236 CLIENT *cl; 237 struct xucred *xucred; 238 { 239 int ngroups; 240 241 ngroups = xucred->cr_ngroups - 1; 242 if (ngroups > NGRPS) 243 ngroups = NGRPS; 244 if (cl->cl_auth != NULL) 245 cl->cl_auth->ah_ops->ah_destroy(cl->cl_auth); 246 cl->cl_auth = authunix_create(hostname, 247 xucred->cr_uid, 248 xucred->cr_groups[0], 249 ngroups, 250 &xucred->cr_groups[1]); 251 } 252 253 254 /* 255 * test_request -- 256 * Convert a lock LOCKD_MSG into an NLM request, and send it off. 257 */ 258 int 259 test_request(LOCKD_MSG *msg) 260 { 261 CLIENT *cli; 262 struct timeval timeout = {0, 0}; /* No timeout, no response. */ 263 char dummy; 264 265 if (d_calls) 266 syslog(LOG_DEBUG, "test request: %s: %s to %s", 267 msg->lm_nfsv3 ? "V4" : "V1/3", 268 msg->lm_fl.l_type == F_WRLCK ? "write" : "read", 269 from_addr((struct sockaddr *)&msg->lm_addr)); 270 271 if (msg->lm_nfsv3) { 272 struct nlm4_testargs arg4; 273 274 arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; 275 arg4.cookie.n_len = sizeof(msg->lm_msg_ident); 276 arg4.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 277 arg4.alock.caller_name = hostname; 278 arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; 279 arg4.alock.fh.n_len = msg->lm_fh_len; 280 arg4.alock.oh.n_bytes = (char *)&owner; 281 arg4.alock.oh.n_len = sizeof(owner); 282 arg4.alock.svid = msg->lm_msg_ident.pid; 283 arg4.alock.l_offset = msg->lm_fl.l_start; 284 arg4.alock.l_len = msg->lm_fl.l_len; 285 286 if ((cli = get_client( 287 (struct sockaddr *)&msg->lm_addr, 288 NLM_VERS4)) == NULL) 289 return (1); 290 291 set_auth(cli, &msg->lm_cred); 292 (void)clnt_call(cli, NLM_TEST_MSG, 293 (xdrproc_t)xdr_nlm4_testargs, &arg4, 294 (xdrproc_t)xdr_void, &dummy, timeout); 295 } else { 296 struct nlm_testargs arg; 297 298 arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; 299 arg.cookie.n_len = sizeof(msg->lm_msg_ident); 300 arg.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 301 arg.alock.caller_name = hostname; 302 arg.alock.fh.n_bytes = (char *)&msg->lm_fh; 303 arg.alock.fh.n_len = msg->lm_fh_len; 304 arg.alock.oh.n_bytes = (char *)&owner; 305 arg.alock.oh.n_len = sizeof(owner); 306 arg.alock.svid = msg->lm_msg_ident.pid; 307 arg.alock.l_offset = msg->lm_fl.l_start; 308 arg.alock.l_len = msg->lm_fl.l_len; 309 310 if ((cli = get_client( 311 (struct sockaddr *)&msg->lm_addr, 312 NLM_VERS)) == NULL) 313 return (1); 314 315 set_auth(cli, &msg->lm_cred); 316 (void)clnt_call(cli, NLM_TEST_MSG, 317 (xdrproc_t)xdr_nlm_testargs, &arg, 318 (xdrproc_t)xdr_void, &dummy, timeout); 319 } 320 return (0); 321 } 322 323 /* 324 * lock_request -- 325 * Convert a lock LOCKD_MSG into an NLM request, and send it off. 326 */ 327 int 328 lock_request(LOCKD_MSG *msg) 329 { 330 CLIENT *cli; 331 struct nlm4_lockargs arg4; 332 struct nlm_lockargs arg; 333 struct timeval timeout = {0, 0}; /* No timeout, no response. */ 334 char dummy; 335 336 if (d_calls) 337 syslog(LOG_DEBUG, "lock request: %s: %s to %s", 338 msg->lm_nfsv3 ? "V4" : "V1/3", 339 msg->lm_fl.l_type == F_WRLCK ? "write" : "read", 340 from_addr((struct sockaddr *)&msg->lm_addr)); 341 342 if (msg->lm_nfsv3) { 343 arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; 344 arg4.cookie.n_len = sizeof(msg->lm_msg_ident); 345 arg4.block = msg->lm_wait ? 1 : 0; 346 arg4.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 347 arg4.alock.caller_name = hostname; 348 arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; 349 arg4.alock.fh.n_len = msg->lm_fh_len; 350 arg4.alock.oh.n_bytes = (char *)&owner; 351 arg4.alock.oh.n_len = sizeof(owner); 352 arg4.alock.svid = msg->lm_msg_ident.pid; 353 arg4.alock.l_offset = msg->lm_fl.l_start; 354 arg4.alock.l_len = msg->lm_fl.l_len; 355 arg4.reclaim = 0; 356 arg4.state = nsm_state; 357 358 if ((cli = get_client( 359 (struct sockaddr *)&msg->lm_addr, 360 NLM_VERS4)) == NULL) 361 return (1); 362 363 set_auth(cli, &msg->lm_cred); 364 (void)clnt_call(cli, NLM_LOCK_MSG, 365 (xdrproc_t)xdr_nlm4_lockargs, &arg4, 366 (xdrproc_t)xdr_void, &dummy, timeout); 367 } else { 368 arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; 369 arg.cookie.n_len = sizeof(msg->lm_msg_ident); 370 arg.block = msg->lm_wait ? 1 : 0; 371 arg.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; 372 arg.alock.caller_name = hostname; 373 arg.alock.fh.n_bytes = (char *)&msg->lm_fh; 374 arg.alock.fh.n_len = msg->lm_fh_len; 375 arg.alock.oh.n_bytes = (char *)&owner; 376 arg.alock.oh.n_len = sizeof(owner); 377 arg.alock.svid = msg->lm_msg_ident.pid; 378 arg.alock.l_offset = msg->lm_fl.l_start; 379 arg.alock.l_len = msg->lm_fl.l_len; 380 arg.reclaim = 0; 381 arg.state = nsm_state; 382 383 if ((cli = get_client( 384 (struct sockaddr *)&msg->lm_addr, 385 NLM_VERS)) == NULL) 386 return (1); 387 388 set_auth(cli, &msg->lm_cred); 389 (void)clnt_call(cli, NLM_LOCK_MSG, 390 (xdrproc_t)xdr_nlm_lockargs, &arg, 391 (xdrproc_t)xdr_void, &dummy, timeout); 392 } 393 return (0); 394 } 395 396 /* 397 * unlock_request -- 398 * Convert an unlock LOCKD_MSG into an NLM request, and send it off. 399 */ 400 int 401 unlock_request(LOCKD_MSG *msg) 402 { 403 CLIENT *cli; 404 struct nlm4_unlockargs arg4; 405 struct nlm_unlockargs arg; 406 struct timeval timeout = {0, 0}; /* No timeout, no response. */ 407 char dummy; 408 409 if (d_calls) 410 syslog(LOG_DEBUG, "unlock request: %s: to %s", 411 msg->lm_nfsv3 ? "V4" : "V1/3", 412 from_addr((struct sockaddr *)&msg->lm_addr)); 413 414 if (msg->lm_nfsv3) { 415 arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; 416 arg4.cookie.n_len = sizeof(msg->lm_msg_ident); 417 arg4.alock.caller_name = hostname; 418 arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; 419 arg4.alock.fh.n_len = msg->lm_fh_len; 420 arg4.alock.oh.n_bytes = (char *)&owner; 421 arg4.alock.oh.n_len = sizeof(owner); 422 arg4.alock.svid = msg->lm_msg_ident.pid; 423 arg4.alock.l_offset = msg->lm_fl.l_start; 424 arg4.alock.l_len = msg->lm_fl.l_len; 425 426 if ((cli = get_client( 427 (struct sockaddr *)&msg->lm_addr, 428 NLM_VERS4)) == NULL) 429 return (1); 430 431 set_auth(cli, &msg->lm_cred); 432 (void)clnt_call(cli, NLM_UNLOCK_MSG, 433 (xdrproc_t)xdr_nlm4_unlockargs, &arg4, 434 (xdrproc_t)xdr_void, &dummy, timeout); 435 } else { 436 arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; 437 arg.cookie.n_len = sizeof(msg->lm_msg_ident); 438 arg.alock.caller_name = hostname; 439 arg.alock.fh.n_bytes = (char *)&msg->lm_fh; 440 arg.alock.fh.n_len = msg->lm_fh_len; 441 arg.alock.oh.n_bytes = (char *)&owner; 442 arg.alock.oh.n_len = sizeof(owner); 443 arg.alock.svid = msg->lm_msg_ident.pid; 444 arg.alock.l_offset = msg->lm_fl.l_start; 445 arg.alock.l_len = msg->lm_fl.l_len; 446 447 if ((cli = get_client( 448 (struct sockaddr *)&msg->lm_addr, 449 NLM_VERS)) == NULL) 450 return (1); 451 452 set_auth(cli, &msg->lm_cred); 453 (void)clnt_call(cli, NLM_UNLOCK_MSG, 454 (xdrproc_t)xdr_nlm_unlockargs, &arg, 455 (xdrproc_t)xdr_void, &dummy, timeout); 456 } 457 458 return (0); 459 } 460 461 int 462 lock_answer(int pid, netobj *netcookie, int result, int *pid_p, int version) 463 { 464 struct lockd_ans ans; 465 466 if (netcookie->n_len != sizeof(ans.la_msg_ident)) { 467 if (pid == -1) { /* we're screwed */ 468 syslog(LOG_ERR, "inedible nlm cookie"); 469 return -1; 470 } 471 ans.la_msg_ident.pid = pid; 472 ans.la_msg_ident.msg_seq = -1; 473 } else { 474 memcpy(&ans.la_msg_ident, netcookie->n_bytes, 475 sizeof(ans.la_msg_ident)); 476 } 477 478 if (d_calls) 479 syslog(LOG_DEBUG, "lock answer: pid %lu: %s %d", 480 (unsigned long)ans.la_msg_ident.pid, 481 version == NLM_VERS4 ? "nlmv4" : "nlmv3", 482 result); 483 484 ans.la_set_getlk_pid = 0; 485 if (version == NLM_VERS4) 486 switch (result) { 487 case nlm4_granted: 488 ans.la_errno = 0; 489 break; 490 default: 491 ans.la_errno = EACCES; 492 break; 493 case nlm4_denied: 494 if (pid_p == NULL) 495 ans.la_errno = EAGAIN; 496 else { 497 /* this is an answer to a nlm_test msg */ 498 ans.la_set_getlk_pid = 1; 499 ans.la_getlk_pid = *pid_p; 500 ans.la_errno = 0; 501 } 502 break; 503 case nlm4_denied_nolocks: 504 ans.la_errno = EAGAIN; 505 break; 506 case nlm4_blocked: 507 return -1; 508 /* NOTREACHED */ 509 case nlm4_denied_grace_period: 510 ans.la_errno = EAGAIN; 511 break; 512 case nlm4_deadlck: 513 ans.la_errno = EDEADLK; 514 break; 515 case nlm4_rofs: 516 ans.la_errno = EROFS; 517 break; 518 case nlm4_stale_fh: 519 ans.la_errno = ESTALE; 520 break; 521 case nlm4_fbig: 522 ans.la_errno = EFBIG; 523 break; 524 case nlm4_failed: 525 ans.la_errno = EACCES; 526 break; 527 } 528 else 529 switch (result) { 530 case nlm_granted: 531 ans.la_errno = 0; 532 break; 533 default: 534 ans.la_errno = EACCES; 535 break; 536 case nlm_denied: 537 if (pid_p == NULL) 538 ans.la_errno = EAGAIN; 539 else { 540 /* this is an answer to a nlm_test msg */ 541 ans.la_set_getlk_pid = 1; 542 ans.la_getlk_pid = *pid_p; 543 ans.la_errno = 0; 544 } 545 break; 546 case nlm_denied_nolocks: 547 ans.la_errno = EAGAIN; 548 break; 549 case nlm_blocked: 550 return -1; 551 /* NOTREACHED */ 552 case nlm_denied_grace_period: 553 ans.la_errno = EAGAIN; 554 break; 555 case nlm_deadlck: 556 ans.la_errno = EDEADLK; 557 break; 558 } 559 560 if (nfslockdans(LOCKD_ANS_VERSION, &ans)) { 561 syslog(((errno == EPIPE || errno == ESRCH) ? 562 LOG_INFO : LOG_ERR), 563 "process %lu: %m", (u_long)ans.la_msg_ident.pid); 564 return -1; 565 } 566 return 0; 567 } 568 569 /* 570 * show -- 571 * Display the contents of a kernel LOCKD_MSG structure. 572 */ 573 void 574 show(LOCKD_MSG *mp) 575 { 576 static char hex[] = "0123456789abcdef"; 577 struct fid *fidp; 578 fsid_t *fsidp; 579 size_t len; 580 u_int8_t *p, *t, buf[NFS_SMALLFH*3+1]; 581 582 syslog(LOG_DEBUG, "process ID: %lu\n", (long)mp->lm_msg_ident.pid); 583 584 fsidp = (fsid_t *)&mp->lm_fh; 585 fidp = (struct fid *)((u_int8_t *)&mp->lm_fh + sizeof(fsid_t)); 586 587 for (t = buf, p = (u_int8_t *)mp->lm_fh, 588 len = mp->lm_fh_len; 589 len > 0; ++p, --len) { 590 *t++ = '\\'; 591 *t++ = hex[(*p & 0xf0) >> 4]; 592 *t++ = hex[*p & 0x0f]; 593 } 594 *t = '\0'; 595 596 syslog(LOG_DEBUG, "fh_len %d, fh %s\n", (int)mp->lm_fh_len, buf); 597 598 /* Show flock structure. */ 599 syslog(LOG_DEBUG, "start %qu; len %qu; pid %lu; type %d; whence %d\n", 600 (unsigned long long)mp->lm_fl.l_start, 601 (unsigned long long)mp->lm_fl.l_len, (u_long)mp->lm_fl.l_pid, 602 mp->lm_fl.l_type, mp->lm_fl.l_whence); 603 604 /* Show wait flag. */ 605 syslog(LOG_DEBUG, "wait was %s\n", mp->lm_wait ? "set" : "not set"); 606 } 607