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 49 /* 50 * Mapping of old NFS Version 2 RPC numbers to generic numbers. 51 */ 52 static int newnfs_nfsv3_procid[NFS_V3NPROCS] = { 53 NFSPROC_NULL, 54 NFSPROC_GETATTR, 55 NFSPROC_SETATTR, 56 NFSPROC_NOOP, 57 NFSPROC_LOOKUP, 58 NFSPROC_READLINK, 59 NFSPROC_READ, 60 NFSPROC_NOOP, 61 NFSPROC_WRITE, 62 NFSPROC_CREATE, 63 NFSPROC_REMOVE, 64 NFSPROC_RENAME, 65 NFSPROC_LINK, 66 NFSPROC_SYMLINK, 67 NFSPROC_MKDIR, 68 NFSPROC_RMDIR, 69 NFSPROC_READDIR, 70 NFSPROC_FSSTAT, 71 NFSPROC_NOOP, 72 NFSPROC_NOOP, 73 NFSPROC_NOOP, 74 NFSPROC_NOOP, 75 }; 76 77 78 SYSCTL_DECL(_vfs_nfsd); 79 80 SVCPOOL *nfsrvd_pool; 81 82 static int nfs_privport = 0; 83 SYSCTL_INT(_vfs_nfsd, OID_AUTO, nfs_privport, CTLFLAG_RW, 84 &nfs_privport, 0, 85 "Only allow clients using a privileged port for NFSv2 and 3"); 86 87 static int nfs_minvers = NFS_VER2; 88 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_min_nfsvers, CTLFLAG_RW, 89 &nfs_minvers, 0, "The lowest version of NFS handled by the server"); 90 91 static int nfs_maxvers = NFS_VER4; 92 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_max_nfsvers, CTLFLAG_RW, 93 &nfs_maxvers, 0, "The highest version of NFS handled by the server"); 94 95 static int nfs_proc(struct nfsrv_descript *, u_int32_t, struct socket *, 96 u_int64_t, struct nfsrvcache **); 97 98 extern u_long sb_max_adj; 99 extern int newnfs_numnfsd; 100 extern struct proc *nfsd_master_proc; 101 102 /* 103 * NFS server system calls 104 */ 105 106 static void 107 nfssvc_program(struct svc_req *rqst, SVCXPRT *xprt) 108 { 109 struct nfsrv_descript nd; 110 struct nfsrvcache *rp = NULL; 111 int cacherep, credflavor; 112 113 memset(&nd, 0, sizeof(nd)); 114 if (rqst->rq_vers == NFS_VER2) { 115 if (rqst->rq_proc > NFSV2PROC_STATFS) { 116 svcerr_noproc(rqst); 117 svc_freereq(rqst); 118 return; 119 } 120 nd.nd_procnum = newnfs_nfsv3_procid[rqst->rq_proc]; 121 nd.nd_flag = ND_NFSV2; 122 } else if (rqst->rq_vers == NFS_VER3) { 123 if (rqst->rq_proc >= NFS_V3NPROCS) { 124 svcerr_noproc(rqst); 125 svc_freereq(rqst); 126 return; 127 } 128 nd.nd_procnum = rqst->rq_proc; 129 nd.nd_flag = ND_NFSV3; 130 } else { 131 if (rqst->rq_proc != NFSPROC_NULL && 132 rqst->rq_proc != NFSV4PROC_COMPOUND) { 133 svcerr_noproc(rqst); 134 svc_freereq(rqst); 135 return; 136 } 137 nd.nd_procnum = rqst->rq_proc; 138 nd.nd_flag = ND_NFSV4; 139 } 140 141 /* 142 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 - 143 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP 144 * mounts. 145 */ 146 nd.nd_mrep = rqst->rq_args; 147 rqst->rq_args = NULL; 148 newnfs_realign(&nd.nd_mrep); 149 nd.nd_md = nd.nd_mrep; 150 nd.nd_dpos = mtod(nd.nd_md, caddr_t); 151 nd.nd_nam = svc_getrpccaller(rqst); 152 nd.nd_nam2 = rqst->rq_addr; 153 nd.nd_mreq = NULL; 154 nd.nd_cred = NULL; 155 156 if (nfs_privport && (nd.nd_flag & ND_NFSV4) == 0) { 157 /* Check if source port is privileged */ 158 u_short port; 159 struct sockaddr *nam = nd.nd_nam; 160 struct sockaddr_in *sin; 161 162 sin = (struct sockaddr_in *)nam; 163 /* 164 * INET/INET6 - same code: 165 * sin_port and sin6_port are at same offset 166 */ 167 port = ntohs(sin->sin_port); 168 if (port >= IPPORT_RESERVED && 169 nd.nd_procnum != NFSPROC_NULL) { 170 #ifdef INET6 171 char b6[INET6_ADDRSTRLEN]; 172 #if defined(KLD_MODULE) 173 /* Do not use ip6_sprintf: the nfs module should work without INET6. */ 174 #define ip6_sprintf(buf, a) \ 175 (sprintf((buf), "%x:%x:%x:%x:%x:%x:%x:%x", \ 176 (a)->s6_addr16[0], (a)->s6_addr16[1], \ 177 (a)->s6_addr16[2], (a)->s6_addr16[3], \ 178 (a)->s6_addr16[4], (a)->s6_addr16[5], \ 179 (a)->s6_addr16[6], (a)->s6_addr16[7]), \ 180 (buf)) 181 #endif 182 #endif 183 printf("NFS request from unprivileged port (%s:%d)\n", 184 #ifdef INET6 185 sin->sin_family == AF_INET6 ? 186 ip6_sprintf(b6, &satosin6(sin)->sin6_addr) : 187 #if defined(KLD_MODULE) 188 #undef ip6_sprintf 189 #endif 190 #endif 191 inet_ntoa(sin->sin_addr), port); 192 svcerr_weakauth(rqst); 193 svc_freereq(rqst); 194 m_freem(nd.nd_mrep); 195 return; 196 } 197 } 198 199 if (nd.nd_procnum != NFSPROC_NULL) { 200 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) { 201 svcerr_weakauth(rqst); 202 svc_freereq(rqst); 203 m_freem(nd.nd_mrep); 204 return; 205 } 206 207 /* Set the flag based on credflavor */ 208 if (credflavor == RPCSEC_GSS_KRB5) { 209 nd.nd_flag |= ND_GSS; 210 } else if (credflavor == RPCSEC_GSS_KRB5I) { 211 nd.nd_flag |= (ND_GSS | ND_GSSINTEGRITY); 212 } else if (credflavor == RPCSEC_GSS_KRB5P) { 213 nd.nd_flag |= (ND_GSS | ND_GSSPRIVACY); 214 } else if (credflavor != AUTH_SYS) { 215 svcerr_weakauth(rqst); 216 svc_freereq(rqst); 217 m_freem(nd.nd_mrep); 218 return; 219 } 220 221 #ifdef MAC 222 mac_cred_associate_nfsd(nd.nd_cred); 223 #endif 224 if ((nd.nd_flag & ND_NFSV4) != 0) { 225 nd.nd_repstat = nfsvno_v4rootexport(&nd); 226 if (nd.nd_repstat != 0) { 227 svcerr_weakauth(rqst); 228 svc_freereq(rqst); 229 m_freem(nd.nd_mrep); 230 return; 231 } 232 } 233 234 cacherep = nfs_proc(&nd, rqst->rq_xid, xprt->xp_socket, 235 xprt->xp_sockref, &rp); 236 } else { 237 NFSMGET(nd.nd_mreq); 238 nd.nd_mreq->m_len = 0; 239 cacherep = RC_REPLY; 240 } 241 if (nd.nd_mrep != NULL) 242 m_freem(nd.nd_mrep); 243 244 if (nd.nd_cred != NULL) 245 crfree(nd.nd_cred); 246 247 if (cacherep == RC_DROPIT) { 248 if (nd.nd_mreq != NULL) 249 m_freem(nd.nd_mreq); 250 svc_freereq(rqst); 251 return; 252 } 253 254 if (nd.nd_mreq == NULL) { 255 svcerr_decode(rqst); 256 svc_freereq(rqst); 257 return; 258 } 259 260 if (nd.nd_repstat & NFSERR_AUTHERR) { 261 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR); 262 if (nd.nd_mreq != NULL) 263 m_freem(nd.nd_mreq); 264 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) { 265 svcerr_systemerr(rqst); 266 } 267 if (rp != NULL) 268 nfsrvd_sentcache(rp, xprt->xp_socket, 0); 269 svc_freereq(rqst); 270 } 271 272 /* 273 * Check the cache and, optionally, do the RPC. 274 * Return the appropriate cache response. 275 */ 276 static int 277 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, struct socket *so, 278 u_int64_t sockref, struct nfsrvcache **rpp) 279 { 280 struct thread *td = curthread; 281 int cacherep = RC_DOIT, isdgram; 282 283 *rpp = NULL; 284 if (nd->nd_nam2 == NULL) { 285 nd->nd_flag |= ND_STREAMSOCK; 286 isdgram = 0; 287 } else { 288 isdgram = 1; 289 } 290 NFSGETTIME(&nd->nd_starttime); 291 292 /* 293 * Two cases: 294 * 1 - For NFSv2 over UDP, if we are near our malloc/mget 295 * limit, just drop the request. There is no 296 * NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the 297 * client will timeout/retry over UDP in a little while. 298 * 2 - nd_repstat == 0 && nd_mreq == NULL, which 299 * means a normal nfs rpc, so check the cache 300 */ 301 if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL && 302 nfsrv_mallocmget_limit()) { 303 cacherep = RC_DROPIT; 304 } else { 305 /* 306 * For NFSv3, play it safe and assume that the client is 307 * doing retries on the same TCP connection. 308 */ 309 if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) == 310 ND_STREAMSOCK) 311 nd->nd_flag |= ND_SAMETCPCONN; 312 nd->nd_retxid = xid; 313 nd->nd_tcpconntime = NFSD_MONOSEC; 314 nd->nd_sockref = sockref; 315 cacherep = nfsrvd_getcache(nd, so); 316 } 317 318 /* 319 * Handle the request. There are three cases. 320 * RC_DOIT - do the RPC 321 * RC_REPLY - return the reply already created 322 * RC_DROPIT - just throw the request away 323 */ 324 if (cacherep == RC_DOIT) { 325 nfsrvd_dorpc(nd, isdgram, td); 326 if (nd->nd_repstat == NFSERR_DONTREPLY) 327 cacherep = RC_DROPIT; 328 else 329 cacherep = RC_REPLY; 330 *rpp = nfsrvd_updatecache(nd, so); 331 } 332 return (cacherep); 333 } 334 335 /* 336 * Adds a socket to the list for servicing by nfsds. 337 */ 338 int 339 nfsrvd_addsock(struct file *fp) 340 { 341 int siz; 342 struct socket *so; 343 int error; 344 SVCXPRT *xprt; 345 static u_int64_t sockref = 0; 346 347 so = fp->f_data; 348 349 siz = sb_max_adj; 350 error = soreserve(so, siz, siz); 351 if (error) { 352 return (error); 353 } 354 355 /* 356 * Steal the socket from userland so that it doesn't close 357 * unexpectedly. 358 */ 359 if (so->so_type == SOCK_DGRAM) 360 xprt = svc_dg_create(nfsrvd_pool, so, 0, 0); 361 else 362 xprt = svc_vc_create(nfsrvd_pool, so, 0, 0); 363 if (xprt) { 364 fp->f_ops = &badfileops; 365 fp->f_data = NULL; 366 xprt->xp_sockref = ++sockref; 367 if (nfs_minvers == NFS_VER2) 368 svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program, 369 NULL); 370 if (nfs_minvers <= NFS_VER3 && nfs_maxvers >= NFS_VER3) 371 svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program, 372 NULL); 373 if (nfs_maxvers >= NFS_VER4) 374 svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program, 375 NULL); 376 SVC_RELEASE(xprt); 377 } 378 379 return (0); 380 } 381 382 /* 383 * Called by nfssvc() for nfsds. Just loops around servicing rpc requests 384 * until it is killed by a signal. 385 */ 386 int 387 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args) 388 { 389 char principal[MAXHOSTNAMELEN + 5]; 390 int error; 391 bool_t ret2, ret3, ret4; 392 393 error = copyinstr(args->principal, principal, sizeof (principal), 394 NULL); 395 if (error) 396 return (error); 397 398 /* 399 * Only the first nfsd actually does any work. The RPC code 400 * adds threads to it as needed. Any extra processes offered 401 * by nfsd just exit. If nfsd is new enough, it will call us 402 * once with a structure that specifies how many threads to 403 * use. 404 */ 405 NFSD_LOCK(); 406 if (newnfs_numnfsd == 0) { 407 newnfs_numnfsd++; 408 409 NFSD_UNLOCK(); 410 411 /* An empty string implies AUTH_SYS only. */ 412 if (principal[0] != '\0') { 413 ret2 = rpc_gss_set_svc_name_call(principal, 414 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER2); 415 ret3 = rpc_gss_set_svc_name_call(principal, 416 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER3); 417 ret4 = rpc_gss_set_svc_name_call(principal, 418 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER4); 419 420 if (!ret2 || !ret3 || !ret4) 421 printf("nfsd: can't register svc name\n"); 422 } 423 424 nfsrvd_pool->sp_minthreads = args->minthreads; 425 nfsrvd_pool->sp_maxthreads = args->maxthreads; 426 427 svc_run(nfsrvd_pool); 428 429 if (principal[0] != '\0') { 430 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2); 431 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3); 432 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4); 433 } 434 435 NFSD_LOCK(); 436 newnfs_numnfsd--; 437 nfsrvd_init(1); 438 } 439 NFSD_UNLOCK(); 440 441 return (0); 442 } 443 444 /* 445 * Initialize the data structures for the server. 446 * Handshake with any new nfsds starting up to avoid any chance of 447 * corruption. 448 */ 449 void 450 nfsrvd_init(int terminating) 451 { 452 453 NFSD_LOCK_ASSERT(); 454 455 if (terminating) { 456 nfsd_master_proc = NULL; 457 NFSD_UNLOCK(); 458 svcpool_destroy(nfsrvd_pool); 459 nfsrvd_pool = NULL; 460 NFSD_LOCK(); 461 } 462 463 NFSD_UNLOCK(); 464 465 nfsrvd_pool = svcpool_create("nfsd", SYSCTL_STATIC_CHILDREN(_vfs_nfsd)); 466 nfsrvd_pool->sp_rcache = NULL; 467 nfsrvd_pool->sp_assign = NULL; 468 nfsrvd_pool->sp_done = NULL; 469 470 NFSD_LOCK(); 471 } 472 473