1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/lockd/svcproc.c 4 * 5 * Lockd server procedures. We don't implement the NLM_*_RES 6 * procedures because we don't use the async procedures. 7 * 8 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> 9 */ 10 11 #include <linux/types.h> 12 #include <linux/time.h> 13 #include <linux/lockd/lockd.h> 14 #include <linux/lockd/share.h> 15 #include <linux/sunrpc/svc_xprt.h> 16 17 #define NLMDBG_FACILITY NLMDBG_CLIENT 18 19 #ifdef CONFIG_LOCKD_V4 20 static __be32 21 cast_to_nlm(__be32 status, u32 vers) 22 { 23 /* Note: status is assumed to be in network byte order !!! */ 24 if (vers != 4){ 25 switch (status) { 26 case nlm_granted: 27 case nlm_lck_denied: 28 case nlm_lck_denied_nolocks: 29 case nlm_lck_blocked: 30 case nlm_lck_denied_grace_period: 31 case nlm_drop_reply: 32 break; 33 case nlm4_deadlock: 34 status = nlm_lck_denied; 35 break; 36 default: 37 status = nlm_lck_denied_nolocks; 38 } 39 } 40 41 return (status); 42 } 43 #define cast_status(status) (cast_to_nlm(status, rqstp->rq_vers)) 44 #else 45 #define cast_status(status) (status) 46 #endif 47 48 /* 49 * Obtain client and file from arguments 50 */ 51 static __be32 52 nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp, 53 struct nlm_host **hostp, struct nlm_file **filp) 54 { 55 struct nlm_host *host = NULL; 56 struct nlm_file *file = NULL; 57 struct nlm_lock *lock = &argp->lock; 58 __be32 error = 0; 59 60 /* nfsd callbacks must have been installed for this procedure */ 61 if (!nlmsvc_ops) 62 return nlm_lck_denied_nolocks; 63 64 /* Obtain host handle */ 65 if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len)) 66 || (argp->monitor && nsm_monitor(host) < 0)) 67 goto no_locks; 68 *hostp = host; 69 70 /* Obtain file pointer. Not used by FREE_ALL call. */ 71 if (filp != NULL) { 72 error = cast_status(nlm_lookup_file(rqstp, &file, &lock->fh)); 73 if (error != 0) 74 goto no_locks; 75 *filp = file; 76 77 /* Set up the missing parts of the file_lock structure */ 78 lock->fl.fl_file = file->f_file; 79 lock->fl.fl_pid = current->tgid; 80 lock->fl.fl_lmops = &nlmsvc_lock_operations; 81 nlmsvc_locks_init_private(&lock->fl, host, (pid_t)lock->svid); 82 if (!lock->fl.fl_owner) { 83 /* lockowner allocation has failed */ 84 nlmsvc_release_host(host); 85 return nlm_lck_denied_nolocks; 86 } 87 } 88 89 return 0; 90 91 no_locks: 92 nlmsvc_release_host(host); 93 if (error) 94 return error; 95 return nlm_lck_denied_nolocks; 96 } 97 98 /* 99 * NULL: Test for presence of service 100 */ 101 static __be32 102 nlmsvc_proc_null(struct svc_rqst *rqstp) 103 { 104 dprintk("lockd: NULL called\n"); 105 return rpc_success; 106 } 107 108 /* 109 * TEST: Check for conflicting lock 110 */ 111 static __be32 112 __nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_res *resp) 113 { 114 struct nlm_args *argp = rqstp->rq_argp; 115 struct nlm_host *host; 116 struct nlm_file *file; 117 __be32 rc = rpc_success; 118 119 dprintk("lockd: TEST called\n"); 120 resp->cookie = argp->cookie; 121 122 /* Obtain client and file */ 123 if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file))) 124 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success; 125 126 /* Now check for conflicting locks */ 127 resp->status = cast_status(nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie)); 128 if (resp->status == nlm_drop_reply) 129 rc = rpc_drop_reply; 130 else 131 dprintk("lockd: TEST status %d vers %d\n", 132 ntohl(resp->status), rqstp->rq_vers); 133 134 nlmsvc_release_lockowner(&argp->lock); 135 nlmsvc_release_host(host); 136 nlm_release_file(file); 137 return rc; 138 } 139 140 static __be32 141 nlmsvc_proc_test(struct svc_rqst *rqstp) 142 { 143 return __nlmsvc_proc_test(rqstp, rqstp->rq_resp); 144 } 145 146 static __be32 147 __nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_res *resp) 148 { 149 struct nlm_args *argp = rqstp->rq_argp; 150 struct nlm_host *host; 151 struct nlm_file *file; 152 __be32 rc = rpc_success; 153 154 dprintk("lockd: LOCK called\n"); 155 156 resp->cookie = argp->cookie; 157 158 /* Obtain client and file */ 159 if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file))) 160 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success; 161 162 #if 0 163 /* If supplied state doesn't match current state, we assume it's 164 * an old request that time-warped somehow. Any error return would 165 * do in this case because it's irrelevant anyway. 166 * 167 * NB: We don't retrieve the remote host's state yet. 168 */ 169 if (host->h_nsmstate && host->h_nsmstate != argp->state) { 170 resp->status = nlm_lck_denied_nolocks; 171 } else 172 #endif 173 174 /* Now try to lock the file */ 175 resp->status = cast_status(nlmsvc_lock(rqstp, file, host, &argp->lock, 176 argp->block, &argp->cookie, 177 argp->reclaim)); 178 if (resp->status == nlm_drop_reply) 179 rc = rpc_drop_reply; 180 else 181 dprintk("lockd: LOCK status %d\n", ntohl(resp->status)); 182 183 nlmsvc_release_lockowner(&argp->lock); 184 nlmsvc_release_host(host); 185 nlm_release_file(file); 186 return rc; 187 } 188 189 static __be32 190 nlmsvc_proc_lock(struct svc_rqst *rqstp) 191 { 192 return __nlmsvc_proc_lock(rqstp, rqstp->rq_resp); 193 } 194 195 static __be32 196 __nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_res *resp) 197 { 198 struct nlm_args *argp = rqstp->rq_argp; 199 struct nlm_host *host; 200 struct nlm_file *file; 201 struct net *net = SVC_NET(rqstp); 202 203 dprintk("lockd: CANCEL called\n"); 204 205 resp->cookie = argp->cookie; 206 207 /* Don't accept requests during grace period */ 208 if (locks_in_grace(net)) { 209 resp->status = nlm_lck_denied_grace_period; 210 return rpc_success; 211 } 212 213 /* Obtain client and file */ 214 if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file))) 215 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success; 216 217 /* Try to cancel request. */ 218 resp->status = cast_status(nlmsvc_cancel_blocked(net, file, &argp->lock)); 219 220 dprintk("lockd: CANCEL status %d\n", ntohl(resp->status)); 221 nlmsvc_release_lockowner(&argp->lock); 222 nlmsvc_release_host(host); 223 nlm_release_file(file); 224 return rpc_success; 225 } 226 227 static __be32 228 nlmsvc_proc_cancel(struct svc_rqst *rqstp) 229 { 230 return __nlmsvc_proc_cancel(rqstp, rqstp->rq_resp); 231 } 232 233 /* 234 * UNLOCK: release a lock 235 */ 236 static __be32 237 __nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_res *resp) 238 { 239 struct nlm_args *argp = rqstp->rq_argp; 240 struct nlm_host *host; 241 struct nlm_file *file; 242 struct net *net = SVC_NET(rqstp); 243 244 dprintk("lockd: UNLOCK called\n"); 245 246 resp->cookie = argp->cookie; 247 248 /* Don't accept new lock requests during grace period */ 249 if (locks_in_grace(net)) { 250 resp->status = nlm_lck_denied_grace_period; 251 return rpc_success; 252 } 253 254 /* Obtain client and file */ 255 if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file))) 256 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success; 257 258 /* Now try to remove the lock */ 259 resp->status = cast_status(nlmsvc_unlock(net, file, &argp->lock)); 260 261 dprintk("lockd: UNLOCK status %d\n", ntohl(resp->status)); 262 nlmsvc_release_lockowner(&argp->lock); 263 nlmsvc_release_host(host); 264 nlm_release_file(file); 265 return rpc_success; 266 } 267 268 static __be32 269 nlmsvc_proc_unlock(struct svc_rqst *rqstp) 270 { 271 return __nlmsvc_proc_unlock(rqstp, rqstp->rq_resp); 272 } 273 274 /* 275 * GRANTED: A server calls us to tell that a process' lock request 276 * was granted 277 */ 278 static __be32 279 __nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_res *resp) 280 { 281 struct nlm_args *argp = rqstp->rq_argp; 282 283 resp->cookie = argp->cookie; 284 285 dprintk("lockd: GRANTED called\n"); 286 resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock); 287 dprintk("lockd: GRANTED status %d\n", ntohl(resp->status)); 288 return rpc_success; 289 } 290 291 static __be32 292 nlmsvc_proc_granted(struct svc_rqst *rqstp) 293 { 294 return __nlmsvc_proc_granted(rqstp, rqstp->rq_resp); 295 } 296 297 /* 298 * This is the generic lockd callback for async RPC calls 299 */ 300 static void nlmsvc_callback_exit(struct rpc_task *task, void *data) 301 { 302 dprintk("lockd: %5u callback returned %d\n", task->tk_pid, 303 -task->tk_status); 304 } 305 306 void nlmsvc_release_call(struct nlm_rqst *call) 307 { 308 if (!refcount_dec_and_test(&call->a_count)) 309 return; 310 nlmsvc_release_host(call->a_host); 311 kfree(call); 312 } 313 314 static void nlmsvc_callback_release(void *data) 315 { 316 nlmsvc_release_call(data); 317 } 318 319 static const struct rpc_call_ops nlmsvc_callback_ops = { 320 .rpc_call_done = nlmsvc_callback_exit, 321 .rpc_release = nlmsvc_callback_release, 322 }; 323 324 /* 325 * `Async' versions of the above service routines. They aren't really, 326 * because we send the callback before the reply proper. I hope this 327 * doesn't break any clients. 328 */ 329 static __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, 330 __be32 (*func)(struct svc_rqst *, struct nlm_res *)) 331 { 332 struct nlm_args *argp = rqstp->rq_argp; 333 struct nlm_host *host; 334 struct nlm_rqst *call; 335 __be32 stat; 336 337 host = nlmsvc_lookup_host(rqstp, 338 argp->lock.caller, 339 argp->lock.len); 340 if (host == NULL) 341 return rpc_system_err; 342 343 call = nlm_alloc_call(host); 344 nlmsvc_release_host(host); 345 if (call == NULL) 346 return rpc_system_err; 347 348 stat = func(rqstp, &call->a_res); 349 if (stat != 0) { 350 nlmsvc_release_call(call); 351 return stat; 352 } 353 354 call->a_flags = RPC_TASK_ASYNC; 355 if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0) 356 return rpc_system_err; 357 return rpc_success; 358 } 359 360 static __be32 nlmsvc_proc_test_msg(struct svc_rqst *rqstp) 361 { 362 dprintk("lockd: TEST_MSG called\n"); 363 return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, __nlmsvc_proc_test); 364 } 365 366 static __be32 nlmsvc_proc_lock_msg(struct svc_rqst *rqstp) 367 { 368 dprintk("lockd: LOCK_MSG called\n"); 369 return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, __nlmsvc_proc_lock); 370 } 371 372 static __be32 nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp) 373 { 374 dprintk("lockd: CANCEL_MSG called\n"); 375 return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, __nlmsvc_proc_cancel); 376 } 377 378 static __be32 379 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp) 380 { 381 dprintk("lockd: UNLOCK_MSG called\n"); 382 return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, __nlmsvc_proc_unlock); 383 } 384 385 static __be32 386 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp) 387 { 388 dprintk("lockd: GRANTED_MSG called\n"); 389 return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, __nlmsvc_proc_granted); 390 } 391 392 /* 393 * SHARE: create a DOS share or alter existing share. 394 */ 395 static __be32 396 nlmsvc_proc_share(struct svc_rqst *rqstp) 397 { 398 struct nlm_args *argp = rqstp->rq_argp; 399 struct nlm_res *resp = rqstp->rq_resp; 400 struct nlm_host *host; 401 struct nlm_file *file; 402 403 dprintk("lockd: SHARE called\n"); 404 405 resp->cookie = argp->cookie; 406 407 /* Don't accept new lock requests during grace period */ 408 if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) { 409 resp->status = nlm_lck_denied_grace_period; 410 return rpc_success; 411 } 412 413 /* Obtain client and file */ 414 if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file))) 415 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success; 416 417 /* Now try to create the share */ 418 resp->status = cast_status(nlmsvc_share_file(host, file, argp)); 419 420 dprintk("lockd: SHARE status %d\n", ntohl(resp->status)); 421 nlmsvc_release_lockowner(&argp->lock); 422 nlmsvc_release_host(host); 423 nlm_release_file(file); 424 return rpc_success; 425 } 426 427 /* 428 * UNSHARE: Release a DOS share. 429 */ 430 static __be32 431 nlmsvc_proc_unshare(struct svc_rqst *rqstp) 432 { 433 struct nlm_args *argp = rqstp->rq_argp; 434 struct nlm_res *resp = rqstp->rq_resp; 435 struct nlm_host *host; 436 struct nlm_file *file; 437 438 dprintk("lockd: UNSHARE called\n"); 439 440 resp->cookie = argp->cookie; 441 442 /* Don't accept requests during grace period */ 443 if (locks_in_grace(SVC_NET(rqstp))) { 444 resp->status = nlm_lck_denied_grace_period; 445 return rpc_success; 446 } 447 448 /* Obtain client and file */ 449 if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file))) 450 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success; 451 452 /* Now try to unshare the file */ 453 resp->status = cast_status(nlmsvc_unshare_file(host, file, argp)); 454 455 dprintk("lockd: UNSHARE status %d\n", ntohl(resp->status)); 456 nlmsvc_release_lockowner(&argp->lock); 457 nlmsvc_release_host(host); 458 nlm_release_file(file); 459 return rpc_success; 460 } 461 462 /* 463 * NM_LOCK: Create an unmonitored lock 464 */ 465 static __be32 466 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp) 467 { 468 struct nlm_args *argp = rqstp->rq_argp; 469 470 dprintk("lockd: NM_LOCK called\n"); 471 472 argp->monitor = 0; /* just clean the monitor flag */ 473 return nlmsvc_proc_lock(rqstp); 474 } 475 476 /* 477 * FREE_ALL: Release all locks and shares held by client 478 */ 479 static __be32 480 nlmsvc_proc_free_all(struct svc_rqst *rqstp) 481 { 482 struct nlm_args *argp = rqstp->rq_argp; 483 struct nlm_host *host; 484 485 /* Obtain client */ 486 if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL)) 487 return rpc_success; 488 489 nlmsvc_free_host_resources(host); 490 nlmsvc_release_host(host); 491 return rpc_success; 492 } 493 494 /* 495 * SM_NOTIFY: private callback from statd (not part of official NLM proto) 496 */ 497 static __be32 498 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp) 499 { 500 struct nlm_reboot *argp = rqstp->rq_argp; 501 502 dprintk("lockd: SM_NOTIFY called\n"); 503 504 if (!nlm_privileged_requester(rqstp)) { 505 char buf[RPC_MAX_ADDRBUFLEN]; 506 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n", 507 svc_print_addr(rqstp, buf, sizeof(buf))); 508 return rpc_system_err; 509 } 510 511 nlm_host_rebooted(SVC_NET(rqstp), argp); 512 return rpc_success; 513 } 514 515 /* 516 * client sent a GRANTED_RES, let's remove the associated block 517 */ 518 static __be32 519 nlmsvc_proc_granted_res(struct svc_rqst *rqstp) 520 { 521 struct nlm_res *argp = rqstp->rq_argp; 522 523 if (!nlmsvc_ops) 524 return rpc_success; 525 526 dprintk("lockd: GRANTED_RES called\n"); 527 528 nlmsvc_grant_reply(&argp->cookie, argp->status); 529 return rpc_success; 530 } 531 532 /* 533 * NLM Server procedures. 534 */ 535 536 #define nlmsvc_encode_norep nlmsvc_encode_void 537 #define nlmsvc_decode_norep nlmsvc_decode_void 538 #define nlmsvc_decode_testres nlmsvc_decode_void 539 #define nlmsvc_decode_lockres nlmsvc_decode_void 540 #define nlmsvc_decode_unlockres nlmsvc_decode_void 541 #define nlmsvc_decode_cancelres nlmsvc_decode_void 542 #define nlmsvc_decode_grantedres nlmsvc_decode_void 543 544 #define nlmsvc_proc_none nlmsvc_proc_null 545 #define nlmsvc_proc_test_res nlmsvc_proc_null 546 #define nlmsvc_proc_lock_res nlmsvc_proc_null 547 #define nlmsvc_proc_cancel_res nlmsvc_proc_null 548 #define nlmsvc_proc_unlock_res nlmsvc_proc_null 549 550 struct nlm_void { int dummy; }; 551 552 #define PROC(name, xargt, xrest, argt, rest, respsize) \ 553 { .pc_func = nlmsvc_proc_##name, \ 554 .pc_decode = nlmsvc_decode_##xargt, \ 555 .pc_encode = nlmsvc_encode_##xrest, \ 556 .pc_release = NULL, \ 557 .pc_argsize = sizeof(struct nlm_##argt), \ 558 .pc_ressize = sizeof(struct nlm_##rest), \ 559 .pc_xdrressize = respsize, \ 560 } 561 562 #define Ck (1+XDR_QUADLEN(NLM_MAXCOOKIELEN)) /* cookie */ 563 #define St 1 /* status */ 564 #define No (1+1024/4) /* Net Obj */ 565 #define Rg 2 /* range - offset + size */ 566 567 const struct svc_procedure nlmsvc_procedures[] = { 568 PROC(null, void, void, void, void, 1), 569 PROC(test, testargs, testres, args, res, Ck+St+2+No+Rg), 570 PROC(lock, lockargs, res, args, res, Ck+St), 571 PROC(cancel, cancargs, res, args, res, Ck+St), 572 PROC(unlock, unlockargs, res, args, res, Ck+St), 573 PROC(granted, testargs, res, args, res, Ck+St), 574 PROC(test_msg, testargs, norep, args, void, 1), 575 PROC(lock_msg, lockargs, norep, args, void, 1), 576 PROC(cancel_msg, cancargs, norep, args, void, 1), 577 PROC(unlock_msg, unlockargs, norep, args, void, 1), 578 PROC(granted_msg, testargs, norep, args, void, 1), 579 PROC(test_res, testres, norep, res, void, 1), 580 PROC(lock_res, lockres, norep, res, void, 1), 581 PROC(cancel_res, cancelres, norep, res, void, 1), 582 PROC(unlock_res, unlockres, norep, res, void, 1), 583 PROC(granted_res, res, norep, res, void, 1), 584 /* statd callback */ 585 PROC(sm_notify, reboot, void, reboot, void, 1), 586 PROC(none, void, void, void, void, 1), 587 PROC(none, void, void, void, void, 1), 588 PROC(none, void, void, void, void, 1), 589 PROC(share, shareargs, shareres, args, res, Ck+St+1), 590 PROC(unshare, shareargs, shareres, args, res, Ck+St+1), 591 PROC(nm_lock, lockargs, res, args, res, Ck+St), 592 PROC(free_all, notify, void, args, void, 0), 593 594 }; 595