fs/lockd/svc4proc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/fs/lockd/svc4proc.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 /*
  20  * Obtain client and file from arguments
  21  */
  22 static __be32
  23 nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  24                         struct nlm_host **hostp, struct nlm_file **filp)
  25 {
  26         struct nlm_host         *host = NULL;
  27         struct nlm_file         *file = NULL;
  28         struct nlm_lock         *lock = &argp->lock;
  29         __be32                  error = 0;
  30
  31         /* nfsd callbacks must have been installed for this procedure */
  32         if (!nlmsvc_ops)
  33                 return nlm_lck_denied_nolocks;
  34
  35         /* Obtain host handle */
  36         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  37          || (argp->monitor && nsm_monitor(host) < 0))
  38                 goto no_locks;
  39         *hostp = host;
  40
  41         /* Obtain file pointer. Not used by FREE_ALL call. */
  42         if (filp != NULL) {
  43                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  44                         goto no_locks;
  45                 *filp = file;
  46
  47                 /* Set up the missing parts of the file_lock structure */
  48                 lock->fl.fl_file  = file->f_file;
  49                 lock->fl.fl_owner = (fl_owner_t) host;
  50                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  51         }
  52
  53         return 0;
  54
  55 no_locks:
  56         nlmsvc_release_host(host);
  57         if (error)
  58                 return error;
  59         return nlm_lck_denied_nolocks;
  60 }
  61
  62 /*
  63  * NULL: Test for presence of service
  64  */
  65 static __be32
  66 nlm4svc_proc_null(struct svc_rqst *rqstp)
  67 {
  68         dprintk("lockd: NULL          called\n");
  69         return rpc_success;
  70 }
  71
  72 /*
  73  * TEST: Check for conflicting lock
  74  */
  75 static __be32
  76 __nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_res *resp)
  77 {
  78         struct nlm_args *argp = rqstp->rq_argp;
  79         struct nlm_host *host;
  80         struct nlm_file *file;
  81         __be32 rc = rpc_success;
  82
  83         dprintk("lockd: TEST4        called\n");
  84         resp->cookie = argp->cookie;
  85
  86         /* Obtain client and file */
  87         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  88                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  89
  90         /* Now check for conflicting locks */
  91         resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
  92         if (resp->status == nlm_drop_reply)
  93                 rc = rpc_drop_reply;
  94         else
  95                 dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
  96
  97         nlmsvc_release_host(host);
  98         nlm_release_file(file);
  99         return rc;
 100 }
 101
 102 static __be32
 103 nlm4svc_proc_test(struct svc_rqst *rqstp)
 104 {
 105         return __nlm4svc_proc_test(rqstp, rqstp->rq_resp);
 106 }
 107
 108 static __be32
 109 __nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_res *resp)
 110 {
 111         struct nlm_args *argp = rqstp->rq_argp;
 112         struct nlm_host *host;
 113         struct nlm_file *file;
 114         __be32 rc = rpc_success;
 115
 116         dprintk("lockd: LOCK          called\n");
 117
 118         resp->cookie = argp->cookie;
 119
 120         /* Obtain client and file */
 121         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 122                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 123
 124 #if 0
 125         /* If supplied state doesn't match current state, we assume it's
 126          * an old request that time-warped somehow. Any error return would
 127          * do in this case because it's irrelevant anyway.
 128          *
 129          * NB: We don't retrieve the remote host's state yet.
 130          */
 131         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 132                 resp->status = nlm_lck_denied_nolocks;
 133         } else
 134 #endif
 135
 136         /* Now try to lock the file */
 137         resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
 138                                         argp->block, &argp->cookie,
 139                                         argp->reclaim);
 140         if (resp->status == nlm_drop_reply)
 141                 rc = rpc_drop_reply;
 142         else
 143                 dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
 144
 145         nlmsvc_release_host(host);
 146         nlm_release_file(file);
 147         return rc;
 148 }
 149
 150 static __be32
 151 nlm4svc_proc_lock(struct svc_rqst *rqstp)
 152 {
 153         return __nlm4svc_proc_lock(rqstp, rqstp->rq_resp);
 154 }
 155
 156 static __be32
 157 __nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_res *resp)
 158 {
 159         struct nlm_args *argp = rqstp->rq_argp;
 160         struct nlm_host *host;
 161         struct nlm_file *file;
 162
 163         dprintk("lockd: CANCEL        called\n");
 164
 165         resp->cookie = argp->cookie;
 166
 167         /* Don't accept requests during grace period */
 168         if (locks_in_grace(SVC_NET(rqstp))) {
 169                 resp->status = nlm_lck_denied_grace_period;
 170                 return rpc_success;
 171         }
 172
 173         /* Obtain client and file */
 174         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 175                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 176
 177         /* Try to cancel request. */
 178         resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
 179
 180         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 181         nlmsvc_release_host(host);
 182         nlm_release_file(file);
 183         return rpc_success;
 184 }
 185
 186 static __be32
 187 nlm4svc_proc_cancel(struct svc_rqst *rqstp)
 188 {
 189         return __nlm4svc_proc_cancel(rqstp, rqstp->rq_resp);
 190 }
 191
 192 /*
 193  * UNLOCK: release a lock
 194  */
 195 static __be32
 196 __nlm4svc_proc_unlock(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
 202         dprintk("lockd: UNLOCK        called\n");
 203
 204         resp->cookie = argp->cookie;
 205
 206         /* Don't accept new lock requests during grace period */
 207         if (locks_in_grace(SVC_NET(rqstp))) {
 208                 resp->status = nlm_lck_denied_grace_period;
 209                 return rpc_success;
 210         }
 211
 212         /* Obtain client and file */
 213         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 214                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 215
 216         /* Now try to remove the lock */
 217         resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
 218
 219         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 220         nlmsvc_release_host(host);
 221         nlm_release_file(file);
 222         return rpc_success;
 223 }
 224
 225 static __be32
 226 nlm4svc_proc_unlock(struct svc_rqst *rqstp)
 227 {
 228         return __nlm4svc_proc_unlock(rqstp, rqstp->rq_resp);
 229 }
 230
 231 /*
 232  * GRANTED: A server calls us to tell that a process' lock request
 233  * was granted
 234  */
 235 static __be32
 236 __nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_res *resp)
 237 {
 238         struct nlm_args *argp = rqstp->rq_argp;
 239
 240         resp->cookie = argp->cookie;
 241
 242         dprintk("lockd: GRANTED       called\n");
 243         resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
 244         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 245         return rpc_success;
 246 }
 247
 248 static __be32
 249 nlm4svc_proc_granted(struct svc_rqst *rqstp)
 250 {
 251         return __nlm4svc_proc_granted(rqstp, rqstp->rq_resp);
 252 }
 253
 254 /*
 255  * This is the generic lockd callback for async RPC calls
 256  */
 257 static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
 258 {
 259         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 260                         -task->tk_status);
 261 }
 262
 263 static void nlm4svc_callback_release(void *data)
 264 {
 265         nlmsvc_release_call(data);
 266 }
 267
 268 static const struct rpc_call_ops nlm4svc_callback_ops = {
 269         .rpc_call_done = nlm4svc_callback_exit,
 270         .rpc_release = nlm4svc_callback_release,
 271 };
 272
 273 /*
 274  * `Async' versions of the above service routines. They aren't really,
 275  * because we send the callback before the reply proper. I hope this
 276  * doesn't break any clients.
 277  */
 278 static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc,
 279                 __be32 (*func)(struct svc_rqst *,  struct nlm_res *))
 280 {
 281         struct nlm_args *argp = rqstp->rq_argp;
 282         struct nlm_host *host;
 283         struct nlm_rqst *call;
 284         __be32 stat;
 285
 286         host = nlmsvc_lookup_host(rqstp,
 287                                   argp->lock.caller,
 288                                   argp->lock.len);
 289         if (host == NULL)
 290                 return rpc_system_err;
 291
 292         call = nlm_alloc_call(host);
 293         nlmsvc_release_host(host);
 294         if (call == NULL)
 295                 return rpc_system_err;
 296
 297         stat = func(rqstp, &call->a_res);
 298         if (stat != 0) {
 299                 nlmsvc_release_call(call);
 300                 return stat;
 301         }
 302
 303         call->a_flags = RPC_TASK_ASYNC;
 304         if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
 305                 return rpc_system_err;
 306         return rpc_success;
 307 }
 308
 309 static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp)
 310 {
 311         dprintk("lockd: TEST_MSG      called\n");
 312         return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, __nlm4svc_proc_test);
 313 }
 314
 315 static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp)
 316 {
 317         dprintk("lockd: LOCK_MSG      called\n");
 318         return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, __nlm4svc_proc_lock);
 319 }
 320
 321 static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp)
 322 {
 323         dprintk("lockd: CANCEL_MSG    called\n");
 324         return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, __nlm4svc_proc_cancel);
 325 }
 326
 327 static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp)
 328 {
 329         dprintk("lockd: UNLOCK_MSG    called\n");
 330         return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, __nlm4svc_proc_unlock);
 331 }
 332
 333 static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp)
 334 {
 335         dprintk("lockd: GRANTED_MSG   called\n");
 336         return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, __nlm4svc_proc_granted);
 337 }
 338
 339 /*
 340  * SHARE: create a DOS share or alter existing share.
 341  */
 342 static __be32
 343 nlm4svc_proc_share(struct svc_rqst *rqstp)
 344 {
 345         struct nlm_args *argp = rqstp->rq_argp;
 346         struct nlm_res *resp = rqstp->rq_resp;
 347         struct nlm_host *host;
 348         struct nlm_file *file;
 349
 350         dprintk("lockd: SHARE         called\n");
 351
 352         resp->cookie = argp->cookie;
 353
 354         /* Don't accept new lock requests during grace period */
 355         if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
 356                 resp->status = nlm_lck_denied_grace_period;
 357                 return rpc_success;
 358         }
 359
 360         /* Obtain client and file */
 361         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 362                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 363
 364         /* Now try to create the share */
 365         resp->status = nlmsvc_share_file(host, file, argp);
 366
 367         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 368         nlmsvc_release_host(host);
 369         nlm_release_file(file);
 370         return rpc_success;
 371 }
 372
 373 /*
 374  * UNSHARE: Release a DOS share.
 375  */
 376 static __be32
 377 nlm4svc_proc_unshare(struct svc_rqst *rqstp)
 378 {
 379         struct nlm_args *argp = rqstp->rq_argp;
 380         struct nlm_res *resp = rqstp->rq_resp;
 381         struct nlm_host *host;
 382         struct nlm_file *file;
 383
 384         dprintk("lockd: UNSHARE       called\n");
 385
 386         resp->cookie = argp->cookie;
 387
 388         /* Don't accept requests during grace period */
 389         if (locks_in_grace(SVC_NET(rqstp))) {
 390                 resp->status = nlm_lck_denied_grace_period;
 391                 return rpc_success;
 392         }
 393
 394         /* Obtain client and file */
 395         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 396                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 397
 398         /* Now try to lock the file */
 399         resp->status = nlmsvc_unshare_file(host, file, argp);
 400
 401         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 402         nlmsvc_release_host(host);
 403         nlm_release_file(file);
 404         return rpc_success;
 405 }
 406
 407 /*
 408  * NM_LOCK: Create an unmonitored lock
 409  */
 410 static __be32
 411 nlm4svc_proc_nm_lock(struct svc_rqst *rqstp)
 412 {
 413         struct nlm_args *argp = rqstp->rq_argp;
 414
 415         dprintk("lockd: NM_LOCK       called\n");
 416
 417         argp->monitor = 0;              /* just clean the monitor flag */
 418         return nlm4svc_proc_lock(rqstp);
 419 }
 420
 421 /*
 422  * FREE_ALL: Release all locks and shares held by client
 423  */
 424 static __be32
 425 nlm4svc_proc_free_all(struct svc_rqst *rqstp)
 426 {
 427         struct nlm_args *argp = rqstp->rq_argp;
 428         struct nlm_host *host;
 429
 430         /* Obtain client */
 431         if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
 432                 return rpc_success;
 433
 434         nlmsvc_free_host_resources(host);
 435         nlmsvc_release_host(host);
 436         return rpc_success;
 437 }
 438
 439 /*
 440  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 441  */
 442 static __be32
 443 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp)
 444 {
 445         struct nlm_reboot *argp = rqstp->rq_argp;
 446
 447         dprintk("lockd: SM_NOTIFY     called\n");
 448
 449         if (!nlm_privileged_requester(rqstp)) {
 450                 char buf[RPC_MAX_ADDRBUFLEN];
 451                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 452                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 453                 return rpc_system_err;
 454         }
 455
 456         nlm_host_rebooted(SVC_NET(rqstp), argp);
 457         return rpc_success;
 458 }
 459
 460 /*
 461  * client sent a GRANTED_RES, let's remove the associated block
 462  */
 463 static __be32
 464 nlm4svc_proc_granted_res(struct svc_rqst *rqstp)
 465 {
 466         struct nlm_res *argp = rqstp->rq_argp;
 467
 468         if (!nlmsvc_ops)
 469                 return rpc_success;
 470
 471         dprintk("lockd: GRANTED_RES   called\n");
 472
 473         nlmsvc_grant_reply(&argp->cookie, argp->status);
 474         return rpc_success;
 475 }
 476
 477
 478 /*
 479  * NLM Server procedures.
 480  */
 481
 482 #define nlm4svc_encode_norep    nlm4svc_encode_void
 483 #define nlm4svc_decode_norep    nlm4svc_decode_void
 484 #define nlm4svc_decode_testres  nlm4svc_decode_void
 485 #define nlm4svc_decode_lockres  nlm4svc_decode_void
 486 #define nlm4svc_decode_unlockres        nlm4svc_decode_void
 487 #define nlm4svc_decode_cancelres        nlm4svc_decode_void
 488 #define nlm4svc_decode_grantedres       nlm4svc_decode_void
 489
 490 #define nlm4svc_proc_none       nlm4svc_proc_null
 491 #define nlm4svc_proc_test_res   nlm4svc_proc_null
 492 #define nlm4svc_proc_lock_res   nlm4svc_proc_null
 493 #define nlm4svc_proc_cancel_res nlm4svc_proc_null
 494 #define nlm4svc_proc_unlock_res nlm4svc_proc_null
 495
 496 struct nlm_void                 { int dummy; };
 497
 498 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 499  { .pc_func     = nlm4svc_proc_##name,  \
 500    .pc_decode   = nlm4svc_decode_##xargt,       \
 501    .pc_encode   = nlm4svc_encode_##xrest,       \
 502    .pc_release  = NULL,                                 \
 503    .pc_argsize  = sizeof(struct nlm_##argt),            \
 504    .pc_ressize  = sizeof(struct nlm_##rest),            \
 505    .pc_xdrressize = respsize,                           \
 506  }
 507 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 508 #define No      (1+1024/4)                              /* netobj */
 509 #define St      1                                       /* status */
 510 #define Rg      4                                       /* range (offset + length) */
 511 const struct svc_procedure nlmsvc_procedures4[] = {
 512   PROC(null,            void,           void,           void,   void, 1),
 513   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 514   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 515   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 516   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 517   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 518   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 519   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 520   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 521   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 522   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 523   PROC(test_res,        testres,        norep,          res,    void, 1),
 524   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 525   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 526   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 527   PROC(granted_res,     res,            norep,          res,    void, 1),
 528   /* statd callback */
 529   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 530   PROC(none,            void,           void,           void,   void, 0),
 531   PROC(none,            void,           void,           void,   void, 0),
 532   PROC(none,            void,           void,           void,   void, 0),
 533   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 534   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 535   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 536   PROC(free_all,        notify,         void,           args,   void, 1),
 537
 538 };