1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet6.h" 38 #include "opt_kgssapi.h" 39 40 #include <fs/nfs/nfsport.h> 41 42 #include <rpc/rpc.h> 43 #include <rpc/rpcsec_gss.h> 44 45 #include <security/mac/mac_framework.h> 46 47 NFSDLOCKMUTEX; 48 NFSV4ROOTLOCKMUTEX; 49 struct nfsv4lock nfsd_suspend_lock; 50 51 /* 52 * Mapping of old NFS Version 2 RPC numbers to generic numbers. 53 */ 54 static int newnfs_nfsv3_procid[NFS_V3NPROCS] = { 55 NFSPROC_NULL, 56 NFSPROC_GETATTR, 57 NFSPROC_SETATTR, 58 NFSPROC_NOOP, 59 NFSPROC_LOOKUP, 60 NFSPROC_READLINK, 61 NFSPROC_READ, 62 NFSPROC_NOOP, 63 NFSPROC_WRITE, 64 NFSPROC_CREATE, 65 NFSPROC_REMOVE, 66 NFSPROC_RENAME, 67 NFSPROC_LINK, 68 NFSPROC_SYMLINK, 69 NFSPROC_MKDIR, 70 NFSPROC_RMDIR, 71 NFSPROC_READDIR, 72 NFSPROC_FSSTAT, 73 NFSPROC_NOOP, 74 NFSPROC_NOOP, 75 NFSPROC_NOOP, 76 NFSPROC_NOOP, 77 }; 78 79 80 SYSCTL_DECL(_vfs_nfsd); 81 82 SVCPOOL *nfsrvd_pool; 83 84 static int nfs_privport = 0; 85 SYSCTL_INT(_vfs_nfsd, OID_AUTO, nfs_privport, CTLFLAG_RW, 86 &nfs_privport, 0, 87 "Only allow clients using a privileged port for NFSv2 and 3"); 88 89 static int nfs_minvers = NFS_VER2; 90 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_min_nfsvers, CTLFLAG_RW, 91 &nfs_minvers, 0, "The lowest version of NFS handled by the server"); 92 93 static int nfs_maxvers = NFS_VER4; 94 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_max_nfsvers, CTLFLAG_RW, 95 &nfs_maxvers, 0, "The highest version of NFS handled by the server"); 96 97 static int nfs_proc(struct nfsrv_descript *, u_int32_t, struct socket *, 98 u_int64_t, struct nfsrvcache **); 99 100 extern u_long sb_max_adj; 101 extern int newnfs_numnfsd; 102 extern struct proc *nfsd_master_proc; 103 104 /* 105 * NFS server system calls 106 */ 107 108 static void 109 nfssvc_program(struct svc_req *rqst, SVCXPRT *xprt) 110 { 111 struct nfsrv_descript nd; 112 struct nfsrvcache *rp = NULL; 113 int cacherep, credflavor; 114 115 memset(&nd, 0, sizeof(nd)); 116 if (rqst->rq_vers == NFS_VER2) { 117 if (rqst->rq_proc > NFSV2PROC_STATFS) { 118 svcerr_noproc(rqst); 119 svc_freereq(rqst); 120 goto out; 121 } 122 nd.nd_procnum = newnfs_nfsv3_procid[rqst->rq_proc]; 123 nd.nd_flag = ND_NFSV2; 124 } else if (rqst->rq_vers == NFS_VER3) { 125 if (rqst->rq_proc >= NFS_V3NPROCS) { 126 svcerr_noproc(rqst); 127 svc_freereq(rqst); 128 goto out; 129 } 130 nd.nd_procnum = rqst->rq_proc; 131 nd.nd_flag = ND_NFSV3; 132 } else { 133 if (rqst->rq_proc != NFSPROC_NULL && 134 rqst->rq_proc != NFSV4PROC_COMPOUND) { 135 svcerr_noproc(rqst); 136 svc_freereq(rqst); 137 goto out; 138 } 139 nd.nd_procnum = rqst->rq_proc; 140 nd.nd_flag = ND_NFSV4; 141 } 142 143 /* 144 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 - 145 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP 146 * mounts. 147 */ 148 nd.nd_mrep = rqst->rq_args; 149 rqst->rq_args = NULL; 150 newnfs_realign(&nd.nd_mrep); 151 nd.nd_md = nd.nd_mrep; 152 nd.nd_dpos = mtod(nd.nd_md, caddr_t); 153 nd.nd_nam = svc_getrpccaller(rqst); 154 nd.nd_nam2 = rqst->rq_addr; 155 nd.nd_mreq = NULL; 156 nd.nd_cred = NULL; 157 158 if (nfs_privport && (nd.nd_flag & ND_NFSV4) == 0) { 159 /* Check if source port is privileged */ 160 u_short port; 161 struct sockaddr *nam = nd.nd_nam; 162 struct sockaddr_in *sin; 163 164 sin = (struct sockaddr_in *)nam; 165 /* 166 * INET/INET6 - same code: 167 * sin_port and sin6_port are at same offset 168 */ 169 port = ntohs(sin->sin_port); 170 if (port >= IPPORT_RESERVED && 171 nd.nd_procnum != NFSPROC_NULL) { 172 #ifdef INET6 173 char b6[INET6_ADDRSTRLEN]; 174 #if defined(KLD_MODULE) 175 /* Do not use ip6_sprintf: the nfs module should work without INET6. */ 176 #define ip6_sprintf(buf, a) \ 177 (sprintf((buf), "%x:%x:%x:%x:%x:%x:%x:%x", \ 178 (a)->s6_addr16[0], (a)->s6_addr16[1], \ 179 (a)->s6_addr16[2], (a)->s6_addr16[3], \ 180 (a)->s6_addr16[4], (a)->s6_addr16[5], \ 181 (a)->s6_addr16[6], (a)->s6_addr16[7]), \ 182 (buf)) 183 #endif 184 #endif 185 printf("NFS request from unprivileged port (%s:%d)\n", 186 #ifdef INET6 187 sin->sin_family == AF_INET6 ? 188 ip6_sprintf(b6, &satosin6(sin)->sin6_addr) : 189 #if defined(KLD_MODULE) 190 #undef ip6_sprintf 191 #endif 192 #endif 193 inet_ntoa(sin->sin_addr), port); 194 svcerr_weakauth(rqst); 195 svc_freereq(rqst); 196 m_freem(nd.nd_mrep); 197 goto out; 198 } 199 } 200 201 if (nd.nd_procnum != NFSPROC_NULL) { 202 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) { 203 svcerr_weakauth(rqst); 204 svc_freereq(rqst); 205 m_freem(nd.nd_mrep); 206 goto out; 207 } 208 209 /* Set the flag based on credflavor */ 210 if (credflavor == RPCSEC_GSS_KRB5) { 211 nd.nd_flag |= ND_GSS; 212 } else if (credflavor == RPCSEC_GSS_KRB5I) { 213 nd.nd_flag |= (ND_GSS | ND_GSSINTEGRITY); 214 } else if (credflavor == RPCSEC_GSS_KRB5P) { 215 nd.nd_flag |= (ND_GSS | ND_GSSPRIVACY); 216 } else if (credflavor != AUTH_SYS) { 217 svcerr_weakauth(rqst); 218 svc_freereq(rqst); 219 m_freem(nd.nd_mrep); 220 goto out; 221 } 222 223 #ifdef MAC 224 mac_cred_associate_nfsd(nd.nd_cred); 225 #endif 226 /* 227 * Get a refcnt (shared lock) on nfsd_suspend_lock. 228 * NFSSVC_SUSPENDNFSD will take an exclusive lock on 229 * nfsd_suspend_lock to suspend these threads. 230 * This must be done here, before the check of 231 * nfsv4root exports by nfsvno_v4rootexport(). 232 */ 233 NFSLOCKV4ROOTMUTEX(); 234 nfsv4_getref(&nfsd_suspend_lock, NULL, NFSV4ROOTLOCKMUTEXPTR, 235 NULL); 236 NFSUNLOCKV4ROOTMUTEX(); 237 238 if ((nd.nd_flag & ND_NFSV4) != 0) { 239 nd.nd_repstat = nfsvno_v4rootexport(&nd); 240 if (nd.nd_repstat != 0) { 241 NFSLOCKV4ROOTMUTEX(); 242 nfsv4_relref(&nfsd_suspend_lock); 243 NFSUNLOCKV4ROOTMUTEX(); 244 svcerr_weakauth(rqst); 245 svc_freereq(rqst); 246 m_freem(nd.nd_mrep); 247 goto out; 248 } 249 } 250 251 cacherep = nfs_proc(&nd, rqst->rq_xid, xprt->xp_socket, 252 xprt->xp_sockref, &rp); 253 NFSLOCKV4ROOTMUTEX(); 254 nfsv4_relref(&nfsd_suspend_lock); 255 NFSUNLOCKV4ROOTMUTEX(); 256 } else { 257 NFSMGET(nd.nd_mreq); 258 nd.nd_mreq->m_len = 0; 259 cacherep = RC_REPLY; 260 } 261 if (nd.nd_mrep != NULL) 262 m_freem(nd.nd_mrep); 263 264 if (nd.nd_cred != NULL) 265 crfree(nd.nd_cred); 266 267 if (cacherep == RC_DROPIT) { 268 if (nd.nd_mreq != NULL) 269 m_freem(nd.nd_mreq); 270 svc_freereq(rqst); 271 goto out; 272 } 273 274 if (nd.nd_mreq == NULL) { 275 svcerr_decode(rqst); 276 svc_freereq(rqst); 277 goto out; 278 } 279 280 if (nd.nd_repstat & NFSERR_AUTHERR) { 281 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR); 282 if (nd.nd_mreq != NULL) 283 m_freem(nd.nd_mreq); 284 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) { 285 svcerr_systemerr(rqst); 286 } 287 if (rp != NULL) 288 nfsrvd_sentcache(rp, xprt->xp_socket, 0); 289 svc_freereq(rqst); 290 291 out: 292 NFSEXITCODE(0); 293 } 294 295 /* 296 * Check the cache and, optionally, do the RPC. 297 * Return the appropriate cache response. 298 */ 299 static int 300 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, struct socket *so, 301 u_int64_t sockref, struct nfsrvcache **rpp) 302 { 303 struct thread *td = curthread; 304 int cacherep = RC_DOIT, isdgram; 305 306 *rpp = NULL; 307 if (nd->nd_nam2 == NULL) { 308 nd->nd_flag |= ND_STREAMSOCK; 309 isdgram = 0; 310 } else { 311 isdgram = 1; 312 } 313 314 /* 315 * Two cases: 316 * 1 - For NFSv2 over UDP, if we are near our malloc/mget 317 * limit, just drop the request. There is no 318 * NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the 319 * client will timeout/retry over UDP in a little while. 320 * 2 - nd_repstat == 0 && nd_mreq == NULL, which 321 * means a normal nfs rpc, so check the cache 322 */ 323 if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL && 324 nfsrv_mallocmget_limit()) { 325 cacherep = RC_DROPIT; 326 } else { 327 /* 328 * For NFSv3, play it safe and assume that the client is 329 * doing retries on the same TCP connection. 330 */ 331 if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) == 332 ND_STREAMSOCK) 333 nd->nd_flag |= ND_SAMETCPCONN; 334 nd->nd_retxid = xid; 335 nd->nd_tcpconntime = NFSD_MONOSEC; 336 nd->nd_sockref = sockref; 337 cacherep = nfsrvd_getcache(nd, so); 338 } 339 340 /* 341 * Handle the request. There are three cases. 342 * RC_DOIT - do the RPC 343 * RC_REPLY - return the reply already created 344 * RC_DROPIT - just throw the request away 345 */ 346 if (cacherep == RC_DOIT) { 347 nfsrvd_dorpc(nd, isdgram, td); 348 if (nd->nd_repstat == NFSERR_DONTREPLY) 349 cacherep = RC_DROPIT; 350 else 351 cacherep = RC_REPLY; 352 *rpp = nfsrvd_updatecache(nd, so); 353 } 354 355 NFSEXITCODE2(0, nd); 356 return (cacherep); 357 } 358 359 /* 360 * Adds a socket to the list for servicing by nfsds. 361 */ 362 int 363 nfsrvd_addsock(struct file *fp) 364 { 365 int siz; 366 struct socket *so; 367 int error = 0; 368 SVCXPRT *xprt; 369 static u_int64_t sockref = 0; 370 371 so = fp->f_data; 372 373 siz = sb_max_adj; 374 error = soreserve(so, siz, siz); 375 if (error) 376 goto out; 377 378 /* 379 * Steal the socket from userland so that it doesn't close 380 * unexpectedly. 381 */ 382 if (so->so_type == SOCK_DGRAM) 383 xprt = svc_dg_create(nfsrvd_pool, so, 0, 0); 384 else 385 xprt = svc_vc_create(nfsrvd_pool, so, 0, 0); 386 if (xprt) { 387 fp->f_ops = &badfileops; 388 fp->f_data = NULL; 389 xprt->xp_sockref = ++sockref; 390 if (nfs_minvers == NFS_VER2) 391 svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program, 392 NULL); 393 if (nfs_minvers <= NFS_VER3 && nfs_maxvers >= NFS_VER3) 394 svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program, 395 NULL); 396 if (nfs_maxvers >= NFS_VER4) 397 svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program, 398 NULL); 399 SVC_RELEASE(xprt); 400 } 401 402 out: 403 NFSEXITCODE(error); 404 return (error); 405 } 406 407 /* 408 * Called by nfssvc() for nfsds. Just loops around servicing rpc requests 409 * until it is killed by a signal. 410 */ 411 int 412 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args) 413 { 414 char principal[MAXHOSTNAMELEN + 5]; 415 int error = 0; 416 bool_t ret2, ret3, ret4; 417 418 error = copyinstr(args->principal, principal, sizeof (principal), 419 NULL); 420 if (error) 421 goto out; 422 423 /* 424 * Only the first nfsd actually does any work. The RPC code 425 * adds threads to it as needed. Any extra processes offered 426 * by nfsd just exit. If nfsd is new enough, it will call us 427 * once with a structure that specifies how many threads to 428 * use. 429 */ 430 NFSD_LOCK(); 431 if (newnfs_numnfsd == 0) { 432 newnfs_numnfsd++; 433 434 NFSD_UNLOCK(); 435 436 /* An empty string implies AUTH_SYS only. */ 437 if (principal[0] != '\0') { 438 ret2 = rpc_gss_set_svc_name_call(principal, 439 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER2); 440 ret3 = rpc_gss_set_svc_name_call(principal, 441 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER3); 442 ret4 = rpc_gss_set_svc_name_call(principal, 443 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER4); 444 445 if (!ret2 || !ret3 || !ret4) 446 printf("nfsd: can't register svc name\n"); 447 } 448 449 nfsrvd_pool->sp_minthreads = args->minthreads; 450 nfsrvd_pool->sp_maxthreads = args->maxthreads; 451 452 svc_run(nfsrvd_pool); 453 454 if (principal[0] != '\0') { 455 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2); 456 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3); 457 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4); 458 } 459 460 NFSD_LOCK(); 461 newnfs_numnfsd--; 462 nfsrvd_init(1); 463 } 464 NFSD_UNLOCK(); 465 466 out: 467 NFSEXITCODE(error); 468 return (error); 469 } 470 471 /* 472 * Initialize the data structures for the server. 473 * Handshake with any new nfsds starting up to avoid any chance of 474 * corruption. 475 */ 476 void 477 nfsrvd_init(int terminating) 478 { 479 480 NFSD_LOCK_ASSERT(); 481 482 if (terminating) { 483 nfsd_master_proc = NULL; 484 NFSD_UNLOCK(); 485 svcpool_destroy(nfsrvd_pool); 486 nfsrvd_pool = NULL; 487 NFSD_LOCK(); 488 } 489 490 NFSD_UNLOCK(); 491 492 nfsrvd_pool = svcpool_create("nfsd", SYSCTL_STATIC_CHILDREN(_vfs_nfsd)); 493 nfsrvd_pool->sp_rcache = NULL; 494 nfsrvd_pool->sp_assign = NULL; 495 nfsrvd_pool->sp_done = NULL; 496 497 NFSD_LOCK(); 498 } 499 500