1 /* $NetBSD: nfs_iod.c,v 1.6 2013/10/25 16:01:56 martin Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)nfs_syscalls.c 8.5 (Berkeley) 3/30/95 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: nfs_iod.c,v 1.6 2013/10/25 16:01:56 martin Exp $"); 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/file.h> 44 #include <sys/stat.h> 45 #include <sys/vnode.h> 46 #include <sys/mount.h> 47 #include <sys/proc.h> 48 #include <sys/uio.h> 49 #include <sys/malloc.h> 50 #include <sys/kmem.h> 51 #include <sys/buf.h> 52 #include <sys/mbuf.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/signalvar.h> 56 #include <sys/domain.h> 57 #include <sys/protosw.h> 58 #include <sys/namei.h> 59 #include <sys/syslog.h> 60 #include <sys/filedesc.h> 61 #include <sys/kthread.h> 62 #include <sys/kauth.h> 63 #include <sys/syscallargs.h> 64 65 #include <netinet/in.h> 66 #include <netinet/tcp.h> 67 #include <nfs/xdr_subs.h> 68 #include <nfs/rpcv2.h> 69 #include <nfs/nfsproto.h> 70 #include <nfs/nfs.h> 71 #include <nfs/nfsm_subs.h> 72 #include <nfs/nfsrvcache.h> 73 #include <nfs/nfsmount.h> 74 #include <nfs/nfsnode.h> 75 #include <nfs/nfsrtt.h> 76 #include <nfs/nfs_var.h> 77 78 extern int nuidhash_max; 79 80 /* 81 * locking order: 82 * nfs_iodlist_lock -> nid_lock -> nm_lock 83 */ 84 kmutex_t nfs_iodlist_lock; 85 struct nfs_iodlist nfs_iodlist_idle; 86 struct nfs_iodlist nfs_iodlist_all; 87 int nfs_niothreads = -1; /* == "0, and has never been set" */ 88 int nfs_defect = 0; 89 90 /* 91 * Asynchronous I/O threads for client nfs. 92 * They do read-ahead and write-behind operations on the block I/O cache. 93 * Never returns unless it fails or gets killed. 94 */ 95 96 static void 97 nfssvc_iod(void *arg) 98 { 99 struct buf *bp; 100 struct nfs_iod *myiod; 101 struct nfsmount *nmp; 102 103 myiod = kmem_alloc(sizeof(*myiod), KM_SLEEP); 104 mutex_init(&myiod->nid_lock, MUTEX_DEFAULT, IPL_NONE); 105 cv_init(&myiod->nid_cv, "nfsiod"); 106 myiod->nid_exiting = false; 107 myiod->nid_mount = NULL; 108 mutex_enter(&nfs_iodlist_lock); 109 LIST_INSERT_HEAD(&nfs_iodlist_all, myiod, nid_all); 110 mutex_exit(&nfs_iodlist_lock); 111 112 for (;;) { 113 mutex_enter(&nfs_iodlist_lock); 114 LIST_INSERT_HEAD(&nfs_iodlist_idle, myiod, nid_idle); 115 mutex_exit(&nfs_iodlist_lock); 116 117 mutex_enter(&myiod->nid_lock); 118 while (/*CONSTCOND*/ true) { 119 nmp = myiod->nid_mount; 120 if (nmp) { 121 myiod->nid_mount = NULL; 122 break; 123 } 124 if (__predict_false(myiod->nid_exiting)) { 125 /* 126 * drop nid_lock to preserve locking order. 127 */ 128 mutex_exit(&myiod->nid_lock); 129 mutex_enter(&nfs_iodlist_lock); 130 mutex_enter(&myiod->nid_lock); 131 /* 132 * recheck nid_mount because nfs_asyncio can 133 * pick us in the meantime as we are still on 134 * nfs_iodlist_lock. 135 */ 136 if (myiod->nid_mount != NULL) { 137 mutex_exit(&nfs_iodlist_lock); 138 continue; 139 } 140 LIST_REMOVE(myiod, nid_idle); 141 mutex_exit(&nfs_iodlist_lock); 142 goto quit; 143 } 144 cv_wait(&myiod->nid_cv, &myiod->nid_lock); 145 } 146 mutex_exit(&myiod->nid_lock); 147 148 mutex_enter(&nmp->nm_lock); 149 while ((bp = TAILQ_FIRST(&nmp->nm_bufq)) != NULL) { 150 /* Take one off the front of the list */ 151 TAILQ_REMOVE(&nmp->nm_bufq, bp, b_freelist); 152 nmp->nm_bufqlen--; 153 if (nmp->nm_bufqlen < 2 * nmp->nm_bufqiods) { 154 cv_broadcast(&nmp->nm_aiocv); 155 } 156 mutex_exit(&nmp->nm_lock); 157 KERNEL_LOCK(1, curlwp); 158 (void)nfs_doio(bp); 159 KERNEL_UNLOCK_LAST(curlwp); 160 mutex_enter(&nmp->nm_lock); 161 /* 162 * If there are more than one iod on this mount, 163 * then defect so that the iods can be shared out 164 * fairly between the mounts 165 */ 166 if (nfs_defect && nmp->nm_bufqiods > 1) { 167 break; 168 } 169 } 170 KASSERT(nmp->nm_bufqiods > 0); 171 nmp->nm_bufqiods--; 172 mutex_exit(&nmp->nm_lock); 173 } 174 quit: 175 KASSERT(myiod->nid_mount == NULL); 176 mutex_exit(&myiod->nid_lock); 177 178 cv_destroy(&myiod->nid_cv); 179 mutex_destroy(&myiod->nid_lock); 180 kmem_free(myiod, sizeof(*myiod)); 181 182 kthread_exit(0); 183 } 184 185 void 186 nfs_iodinit(void) 187 { 188 189 mutex_init(&nfs_iodlist_lock, MUTEX_DEFAULT, IPL_NONE); 190 LIST_INIT(&nfs_iodlist_all); 191 LIST_INIT(&nfs_iodlist_idle); 192 } 193 194 void 195 nfs_iodfini(void) 196 { 197 int error __diagused; 198 199 error = nfs_set_niothreads(0); 200 KASSERT(error == 0); 201 mutex_destroy(&nfs_iodlist_lock); 202 } 203 204 int 205 nfs_set_niothreads(int newval) 206 { 207 struct nfs_iod *nid; 208 int error = 0; 209 int hold_count; 210 211 KERNEL_UNLOCK_ALL(curlwp, &hold_count); 212 213 mutex_enter(&nfs_iodlist_lock); 214 /* clamp to sane range */ 215 nfs_niothreads = max(0, min(newval, NFS_MAXASYNCDAEMON)); 216 217 while (nfs_numasync != nfs_niothreads && error == 0) { 218 while (nfs_numasync < nfs_niothreads) { 219 220 /* 221 * kthread_create can wait for pagedaemon and 222 * pagedaemon can wait for nfsiod which needs to acquire 223 * nfs_iodlist_lock. 224 */ 225 226 mutex_exit(&nfs_iodlist_lock); 227 error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, 228 nfssvc_iod, NULL, NULL, "nfsio"); 229 mutex_enter(&nfs_iodlist_lock); 230 if (error) { 231 /* give up */ 232 nfs_niothreads = nfs_numasync; 233 break; 234 } 235 nfs_numasync++; 236 } 237 while (nfs_numasync > nfs_niothreads) { 238 nid = LIST_FIRST(&nfs_iodlist_all); 239 if (nid == NULL) { 240 /* iod has not started yet. */ 241 kpause("nfsiorm", false, hz, &nfs_iodlist_lock); 242 continue; 243 } 244 LIST_REMOVE(nid, nid_all); 245 mutex_enter(&nid->nid_lock); 246 KASSERT(!nid->nid_exiting); 247 nid->nid_exiting = true; 248 cv_signal(&nid->nid_cv); 249 mutex_exit(&nid->nid_lock); 250 nfs_numasync--; 251 } 252 } 253 mutex_exit(&nfs_iodlist_lock); 254 255 KERNEL_LOCK(hold_count, curlwp); 256 return error; 257 } 258 259 /* 260 * Get an authorization string for the uid by having the mount_nfs sitting 261 * on this mount point porpous out of the kernel and do it. 262 */ 263 int 264 nfs_getauth(struct nfsmount *nmp, struct nfsreq *rep, kauth_cred_t cred, char **auth_str, int *auth_len, char *verf_str, int *verf_len, NFSKERBKEY_T key) 265 /* key: return session key */ 266 { 267 int error = 0; 268 269 while ((nmp->nm_iflag & NFSMNT_WAITAUTH) == 0) { 270 nmp->nm_iflag |= NFSMNT_WANTAUTH; 271 (void) tsleep((void *)&nmp->nm_authtype, PSOCK, 272 "nfsauth1", 2 * hz); 273 error = nfs_sigintr(nmp, rep, rep->r_lwp); 274 if (error) { 275 nmp->nm_iflag &= ~NFSMNT_WANTAUTH; 276 return (error); 277 } 278 } 279 nmp->nm_iflag &= ~(NFSMNT_WAITAUTH | NFSMNT_WANTAUTH); 280 nmp->nm_authstr = *auth_str = (char *)malloc(RPCAUTH_MAXSIZ, M_TEMP, M_WAITOK); 281 nmp->nm_authlen = RPCAUTH_MAXSIZ; 282 nmp->nm_verfstr = verf_str; 283 nmp->nm_verflen = *verf_len; 284 nmp->nm_authuid = kauth_cred_geteuid(cred); 285 wakeup((void *)&nmp->nm_authstr); 286 287 /* 288 * And wait for mount_nfs to do its stuff. 289 */ 290 while ((nmp->nm_iflag & NFSMNT_HASAUTH) == 0 && error == 0) { 291 (void) tsleep((void *)&nmp->nm_authlen, PSOCK, 292 "nfsauth2", 2 * hz); 293 error = nfs_sigintr(nmp, rep, rep->r_lwp); 294 } 295 if (nmp->nm_iflag & NFSMNT_AUTHERR) { 296 nmp->nm_iflag &= ~NFSMNT_AUTHERR; 297 error = EAUTH; 298 } 299 if (error) 300 free((void *)*auth_str, M_TEMP); 301 else { 302 *auth_len = nmp->nm_authlen; 303 *verf_len = nmp->nm_verflen; 304 memcpy(key, nmp->nm_key, sizeof (NFSKERBKEY_T)); 305 } 306 nmp->nm_iflag &= ~NFSMNT_HASAUTH; 307 nmp->nm_iflag |= NFSMNT_WAITAUTH; 308 if (nmp->nm_iflag & NFSMNT_WANTAUTH) { 309 nmp->nm_iflag &= ~NFSMNT_WANTAUTH; 310 wakeup((void *)&nmp->nm_authtype); 311 } 312 return (error); 313 } 314 315 /* 316 * Get a nickname authenticator and verifier. 317 */ 318 int 319 nfs_getnickauth(struct nfsmount *nmp, kauth_cred_t cred, char **auth_str, 320 int *auth_len, char *verf_str, int verf_len) 321 { 322 #ifdef NFSKERB 323 struct timeval ktvin; 324 #endif 325 struct timeval ktvout, tv; 326 struct nfsuid *nuidp; 327 u_int32_t *nickp, *verfp; 328 329 memset(&ktvout, 0, sizeof ktvout); /* XXX gcc */ 330 331 #ifdef DIAGNOSTIC 332 if (verf_len < (4 * NFSX_UNSIGNED)) 333 panic("nfs_getnickauth verf too small"); 334 #endif 335 LIST_FOREACH(nuidp, NMUIDHASH(nmp, kauth_cred_geteuid(cred)), nu_hash) { 336 if (kauth_cred_geteuid(nuidp->nu_cr) == kauth_cred_geteuid(cred)) 337 break; 338 } 339 if (!nuidp || nuidp->nu_expire < time_second) 340 return (EACCES); 341 342 /* 343 * Move to the end of the lru list (end of lru == most recently used). 344 */ 345 TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp, nu_lru); 346 TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp, nu_lru); 347 348 nickp = (u_int32_t *)malloc(2 * NFSX_UNSIGNED, M_TEMP, M_WAITOK); 349 *nickp++ = txdr_unsigned(RPCAKN_NICKNAME); 350 *nickp = txdr_unsigned(nuidp->nu_nickname); 351 *auth_str = (char *)nickp; 352 *auth_len = 2 * NFSX_UNSIGNED; 353 354 /* 355 * Now we must encrypt the verifier and package it up. 356 */ 357 verfp = (u_int32_t *)verf_str; 358 *verfp++ = txdr_unsigned(RPCAKN_NICKNAME); 359 getmicrotime(&tv); 360 if (tv.tv_sec > nuidp->nu_timestamp.tv_sec || 361 (tv.tv_sec == nuidp->nu_timestamp.tv_sec && 362 tv.tv_usec > nuidp->nu_timestamp.tv_usec)) 363 nuidp->nu_timestamp = tv; 364 else 365 nuidp->nu_timestamp.tv_usec++; 366 #ifdef NFSKERB 367 ktvin.tv_sec = txdr_unsigned(nuidp->nu_timestamp.tv_sec); 368 ktvin.tv_usec = txdr_unsigned(nuidp->nu_timestamp.tv_usec); 369 370 /* 371 * Now encrypt the timestamp verifier in ecb mode using the session 372 * key. 373 */ 374 XXX 375 #endif 376 377 *verfp++ = ktvout.tv_sec; 378 *verfp++ = ktvout.tv_usec; 379 *verfp = 0; 380 return (0); 381 } 382 383 /* 384 * Save the current nickname in a hash list entry on the mount point. 385 */ 386 int 387 nfs_savenickauth(struct nfsmount *nmp, kauth_cred_t cred, int len, NFSKERBKEY_T key, struct mbuf **mdp, char **dposp, struct mbuf *mrep) 388 { 389 struct nfsuid *nuidp; 390 u_int32_t *tl; 391 int32_t t1; 392 struct mbuf *md = *mdp; 393 struct timeval ktvin, ktvout; 394 u_int32_t nick; 395 char *dpos = *dposp, *cp2; 396 int deltasec, error = 0; 397 398 memset(&ktvout, 0, sizeof ktvout); /* XXX gcc */ 399 400 if (len == (3 * NFSX_UNSIGNED)) { 401 nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED); 402 ktvin.tv_sec = *tl++; 403 ktvin.tv_usec = *tl++; 404 nick = fxdr_unsigned(u_int32_t, *tl); 405 406 /* 407 * Decrypt the timestamp in ecb mode. 408 */ 409 #ifdef NFSKERB 410 XXX 411 #else 412 (void)ktvin.tv_sec; 413 #endif 414 ktvout.tv_sec = fxdr_unsigned(long, ktvout.tv_sec); 415 ktvout.tv_usec = fxdr_unsigned(long, ktvout.tv_usec); 416 deltasec = time_second - ktvout.tv_sec; 417 if (deltasec < 0) 418 deltasec = -deltasec; 419 /* 420 * If ok, add it to the hash list for the mount point. 421 */ 422 if (deltasec <= NFS_KERBCLOCKSKEW) { 423 if (nmp->nm_numuids < nuidhash_max) { 424 nmp->nm_numuids++; 425 nuidp = kmem_alloc(sizeof(*nuidp), KM_SLEEP); 426 } else { 427 nuidp = TAILQ_FIRST(&nmp->nm_uidlruhead); 428 LIST_REMOVE(nuidp, nu_hash); 429 TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp, 430 nu_lru); 431 } 432 nuidp->nu_flag = 0; 433 kauth_cred_seteuid(nuidp->nu_cr, kauth_cred_geteuid(cred)); 434 nuidp->nu_expire = time_second + NFS_KERBTTL; 435 nuidp->nu_timestamp = ktvout; 436 nuidp->nu_nickname = nick; 437 memcpy(nuidp->nu_key, key, sizeof (NFSKERBKEY_T)); 438 TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp, 439 nu_lru); 440 LIST_INSERT_HEAD(NMUIDHASH(nmp, kauth_cred_geteuid(cred)), 441 nuidp, nu_hash); 442 } 443 } else 444 nfsm_adv(nfsm_rndup(len)); 445 nfsmout: 446 *mdp = md; 447 *dposp = dpos; 448 return (error); 449 } 450