xref: /freebsd/sys/fs/nfsserver/nfs_nfsdkrpc.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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  */
35 
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 #include "opt_inet6.h"
40 #include "opt_kgssapi.h"
41 #include "opt_kern_tls.h"
42 
43 #include <fs/nfs/nfsport.h>
44 
45 #include <rpc/rpc.h>
46 #include <rpc/rpcsec_gss.h>
47 #include <rpc/rpcsec_tls.h>
48 
49 #include <fs/nfsserver/nfs_fha_new.h>
50 
51 #include <security/mac/mac_framework.h>
52 
53 NFSDLOCKMUTEX;
54 NFSV4ROOTLOCKMUTEX;
55 char *nfsrv_zeropnfsdat = NULL;
56 
57 /*
58  * Mapping of old NFS Version 2 RPC numbers to generic numbers.
59  */
60 int newnfs_nfsv3_procid[NFS_V3NPROCS] = {
61 	NFSPROC_NULL,
62 	NFSPROC_GETATTR,
63 	NFSPROC_SETATTR,
64 	NFSPROC_NOOP,
65 	NFSPROC_LOOKUP,
66 	NFSPROC_READLINK,
67 	NFSPROC_READ,
68 	NFSPROC_NOOP,
69 	NFSPROC_WRITE,
70 	NFSPROC_CREATE,
71 	NFSPROC_REMOVE,
72 	NFSPROC_RENAME,
73 	NFSPROC_LINK,
74 	NFSPROC_SYMLINK,
75 	NFSPROC_MKDIR,
76 	NFSPROC_RMDIR,
77 	NFSPROC_READDIR,
78 	NFSPROC_FSSTAT,
79 	NFSPROC_NOOP,
80 	NFSPROC_NOOP,
81 	NFSPROC_NOOP,
82 	NFSPROC_NOOP,
83 };
84 
85 SYSCTL_DECL(_vfs_nfsd);
86 
87 NFSD_VNET_DEFINE_STATIC(int, nfs_privport) = 0;
88 SYSCTL_INT(_vfs_nfsd, OID_AUTO, nfs_privport, CTLFLAG_NFSD_VNET | CTLFLAG_RWTUN,
89     &NFSD_VNET_NAME(nfs_privport), 0,
90     "Only allow clients using a privileged port for NFSv2, 3 and 4");
91 
92 NFSD_VNET_DEFINE_STATIC(int, nfs_minvers) = NFS_VER2;
93 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_min_nfsvers,
94     CTLFLAG_NFSD_VNET | CTLFLAG_RWTUN, &NFSD_VNET_NAME(nfs_minvers), 0,
95     "The lowest version of NFS handled by the server");
96 
97 NFSD_VNET_DEFINE_STATIC(int, nfs_maxvers) = NFS_VER4;
98 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_max_nfsvers,
99     CTLFLAG_NFSD_VNET | CTLFLAG_RWTUN, &NFSD_VNET_NAME(nfs_maxvers), 0,
100     "The highest version of NFS handled by the server");
101 
102 static int nfs_proc(struct nfsrv_descript *, u_int32_t, SVCXPRT *xprt,
103     struct nfsrvcache **);
104 
105 extern u_long sb_max_adj;
106 extern int newnfs_numnfsd;
107 extern time_t nfsdev_time;
108 extern int nfsrv_writerpc[NFS_NPROCS];
109 extern volatile int nfsrv_devidcnt;
110 extern struct nfsv4_opflag nfsv4_opflag[NFSV42_NOPS];
111 extern int nfsd_debuglevel;
112 
113 NFSD_VNET_DECLARE(struct proc *, nfsd_master_proc);
114 
115 NFSD_VNET_DEFINE(SVCPOOL *, nfsrvd_pool);
116 NFSD_VNET_DEFINE(int, nfsrv_numnfsd) = 0;
117 NFSD_VNET_DEFINE(struct nfsv4lock, nfsd_suspend_lock);
118 
119 NFSD_VNET_DEFINE_STATIC(bool, nfsrvd_inited) = false;
120 
121 /*
122  * NFS server system calls
123  */
124 
125 static void
126 nfssvc_program(struct svc_req *rqst, SVCXPRT *xprt)
127 {
128 	struct nfsrv_descript nd;
129 	struct nfsrvcache *rp = NULL;
130 	rpc_gss_rawcred_t *rcredp;
131 	int cacherep, credflavor, i, j;
132 	u_char *p;
133 #ifdef KERN_TLS
134 	u_int maxlen;
135 #endif
136 
137 	NFSD_CURVNET_SET_QUIET(NFSD_TD_TO_VNET(curthread));
138 	memset(&nd, 0, sizeof(nd));
139 	if (rqst->rq_vers == NFS_VER2) {
140 		if (rqst->rq_proc > NFSV2PROC_STATFS ||
141 		    newnfs_nfsv3_procid[rqst->rq_proc] == NFSPROC_NOOP) {
142 			svcerr_noproc(rqst);
143 			svc_freereq(rqst);
144 			goto out;
145 		}
146 		nd.nd_procnum = newnfs_nfsv3_procid[rqst->rq_proc];
147 		nd.nd_flag = ND_NFSV2;
148 	} else if (rqst->rq_vers == NFS_VER3) {
149 		if (rqst->rq_proc >= NFS_V3NPROCS) {
150 			svcerr_noproc(rqst);
151 			svc_freereq(rqst);
152 			goto out;
153 		}
154 		nd.nd_procnum = rqst->rq_proc;
155 		nd.nd_flag = ND_NFSV3;
156 	} else {
157 		if (rqst->rq_proc != NFSPROC_NULL &&
158 		    rqst->rq_proc != NFSV4PROC_COMPOUND) {
159 			svcerr_noproc(rqst);
160 			svc_freereq(rqst);
161 			goto out;
162 		}
163 		nd.nd_procnum = rqst->rq_proc;
164 		nd.nd_flag = ND_NFSV4;
165 	}
166 
167 	/*
168 	 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 -
169 	 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP
170 	 * mounts.
171 	 */
172 	nd.nd_mrep = rqst->rq_args;
173 	rqst->rq_args = NULL;
174 	newnfs_realign(&nd.nd_mrep, M_WAITOK);
175 	nd.nd_md = nd.nd_mrep;
176 	nd.nd_dpos = mtod(nd.nd_md, caddr_t);
177 	nd.nd_nam = svc_getrpccaller(rqst);
178 	nd.nd_nam2 = rqst->rq_addr;
179 	nd.nd_mreq = NULL;
180 	nd.nd_cred = NULL;
181 
182 	if (NFSD_VNET(nfs_privport) != 0) {
183 		/* Check if source port is privileged */
184 		u_short port;
185 		struct sockaddr *nam = nd.nd_nam;
186 		struct sockaddr_in *sin;
187 
188 		sin = (struct sockaddr_in *)nam;
189 		/*
190 		 * INET/INET6 - same code:
191 		 *    sin_port and sin6_port are at same offset
192 		 */
193 		port = ntohs(sin->sin_port);
194 		if (port >= IPPORT_RESERVED &&
195 		    nd.nd_procnum != NFSPROC_NULL) {
196 #ifdef INET6
197 			char buf[INET6_ADDRSTRLEN];
198 #else
199 			char buf[INET_ADDRSTRLEN];
200 #endif
201 #ifdef INET6
202 #if defined(KLD_MODULE)
203 			/* Do not use ip6_sprintf: the nfs module should work without INET6. */
204 #define	ip6_sprintf(buf, a)						\
205 			(sprintf((buf), "%x:%x:%x:%x:%x:%x:%x:%x",	\
206 			    (a)->s6_addr16[0], (a)->s6_addr16[1],	\
207 			    (a)->s6_addr16[2], (a)->s6_addr16[3],	\
208 			    (a)->s6_addr16[4], (a)->s6_addr16[5],	\
209 			    (a)->s6_addr16[6], (a)->s6_addr16[7]),	\
210 			    (buf))
211 #endif
212 #endif
213 			printf("NFS request from unprivileged port (%s:%d)\n",
214 #ifdef INET6
215 			    sin->sin_family == AF_INET6 ?
216 			    ip6_sprintf(buf, &satosin6(sin)->sin6_addr) :
217 #if defined(KLD_MODULE)
218 #undef ip6_sprintf
219 #endif
220 #endif
221 			    inet_ntoa_r(sin->sin_addr, buf), port);
222 			svcerr_weakauth(rqst);
223 			svc_freereq(rqst);
224 			m_freem(nd.nd_mrep);
225 			goto out;
226 		}
227 	}
228 
229 	if (nd.nd_procnum != NFSPROC_NULL) {
230 		if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) {
231 			svcerr_weakauth(rqst);
232 			svc_freereq(rqst);
233 			m_freem(nd.nd_mrep);
234 			goto out;
235 		}
236 
237 		/* Set the flag based on credflavor */
238 		if (credflavor == RPCSEC_GSS_KRB5) {
239 			nd.nd_flag |= ND_GSS;
240 		} else if (credflavor == RPCSEC_GSS_KRB5I) {
241 			nd.nd_flag |= (ND_GSS | ND_GSSINTEGRITY);
242 		} else if (credflavor == RPCSEC_GSS_KRB5P) {
243 			nd.nd_flag |= (ND_GSS | ND_GSSPRIVACY);
244 		} else if (credflavor != AUTH_SYS) {
245 			svcerr_weakauth(rqst);
246 			svc_freereq(rqst);
247 			m_freem(nd.nd_mrep);
248 			goto out;
249 		}
250 
251 		/* Acquire the principal name for the RPCSEC_GSS cases. */
252 		if ((nd.nd_flag & (ND_NFSV4 | ND_GSS)) == (ND_NFSV4 | ND_GSS)) {
253 			rcredp = NULL;
254 			rpc_gss_getcred_call(rqst, &rcredp, NULL, NULL);
255 			/*
256 			 * The exported principal name consists of:
257 			 * - TOK_ID bytes with value of 4 and 1.
258 			 * - 2 byte mech length
259 			 * - mech
260 			 * - 4 byte principal name length
261 			 * - principal name
262 			 * A call to gss_import_name() would be an
263 			 * upcall to the gssd, so parse it here.
264 			 * See lib/libgssapi/gss_import_name.c for the
265 			 * above format.
266 			 */
267 			if (rcredp != NULL &&
268 			    rcredp->client_principal->len > 4 &&
269 			    rcredp->client_principal->name[0] == 4 &&
270 			    rcredp->client_principal->name[1] == 1) {
271 				/* Skip over the mech. */
272 				p = &rcredp->client_principal->name[2];
273 				i = (p[0] << 8) | p[1];
274 				p += i + 2;
275 				i += 4;
276 				/*
277 				 * Set "j" to a bogus length so that the
278 				 * "i + j" check will fail unless the below
279 				 * code sets "j" correctly.
280 				 */
281 				j = rcredp->client_principal->len;
282 				if (rcredp->client_principal->len > i + 4) {
283 					j = (p[0] << 24) | (p[1] << 16) |
284 					    (p[2] << 8) | p[3];
285 					i += 4;
286 					p += 4;
287 				}
288 				if (i + j == rcredp->client_principal->len) {
289 					nd.nd_principal = malloc(j + 1, M_TEMP,
290 					    M_WAITOK);
291 					nd.nd_princlen = j;
292 					memcpy(nd.nd_principal, p, j);
293 					nd.nd_principal[j] = '\0';
294 					NFSD_DEBUG(1, "nfssvc_program: "
295 					    "principal=%s\n", nd.nd_principal);
296 				}
297 			}
298 			if (nd.nd_princlen == 0)
299 				printf("nfssvc_program: cannot get RPCSEC_GSS "
300 				    "principal name\n");
301 		}
302 
303 		if ((xprt->xp_tls & RPCTLS_FLAGS_HANDSHAKE) != 0) {
304 			nd.nd_flag |= ND_TLS;
305 			if ((xprt->xp_tls & RPCTLS_FLAGS_VERIFIED) != 0)
306 				nd.nd_flag |= ND_TLSCERT;
307 			if ((xprt->xp_tls & RPCTLS_FLAGS_CERTUSER) != 0)
308 				nd.nd_flag |= ND_TLSCERTUSER;
309 		}
310 		nd.nd_maxextsiz = 16384;
311 #ifdef MAC
312 		mac_cred_associate_nfsd(nd.nd_cred);
313 #endif
314 		/*
315 		 * Get a refcnt (shared lock) on nfsd_suspend_lock.
316 		 * NFSSVC_SUSPENDNFSD will take an exclusive lock on
317 		 * nfsd_suspend_lock to suspend these threads.
318 		 * The call to nfsv4_lock() that precedes nfsv4_getref()
319 		 * ensures that the acquisition of the exclusive lock
320 		 * takes priority over acquisition of the shared lock by
321 		 * waiting for any exclusive lock request to complete.
322 		 * This must be done here, before the check of
323 		 * nfsv4root exports by nfsvno_v4rootexport().
324 		 */
325 		NFSLOCKV4ROOTMUTEX();
326 		nfsv4_lock(&NFSD_VNET(nfsd_suspend_lock), 0, NULL,
327 		    NFSV4ROOTLOCKMUTEXPTR, NULL);
328 		nfsv4_getref(&NFSD_VNET(nfsd_suspend_lock), NULL,
329 		    NFSV4ROOTLOCKMUTEXPTR, NULL);
330 		NFSUNLOCKV4ROOTMUTEX();
331 
332 		if ((nd.nd_flag & ND_NFSV4) != 0) {
333 			nd.nd_repstat = nfsvno_v4rootexport(&nd);
334 			if (nd.nd_repstat != 0) {
335 				NFSLOCKV4ROOTMUTEX();
336 				nfsv4_relref(&NFSD_VNET(nfsd_suspend_lock));
337 				NFSUNLOCKV4ROOTMUTEX();
338 				svcerr_weakauth(rqst);
339 				svc_freereq(rqst);
340 				m_freem(nd.nd_mrep);
341 				goto out;
342 			}
343 		}
344 
345 #ifdef KERN_TLS
346 		if ((xprt->xp_tls & RPCTLS_FLAGS_HANDSHAKE) != 0 &&
347 		    rpctls_getinfo(&maxlen, false, false))
348 			nd.nd_maxextsiz = maxlen;
349 #endif
350 		cacherep = nfs_proc(&nd, rqst->rq_xid, xprt, &rp);
351 		NFSLOCKV4ROOTMUTEX();
352 		nfsv4_relref(&NFSD_VNET(nfsd_suspend_lock));
353 		NFSUNLOCKV4ROOTMUTEX();
354 	} else {
355 		NFSMGET(nd.nd_mreq);
356 		nd.nd_mreq->m_len = 0;
357 		cacherep = RC_REPLY;
358 	}
359 	if (nd.nd_mrep != NULL)
360 		m_freem(nd.nd_mrep);
361 
362 	if (nd.nd_cred != NULL)
363 		crfree(nd.nd_cred);
364 
365 	if (cacherep == RC_DROPIT) {
366 		if (nd.nd_mreq != NULL)
367 			m_freem(nd.nd_mreq);
368 		svc_freereq(rqst);
369 		goto out;
370 	}
371 
372 	if (nd.nd_mreq == NULL) {
373 		svcerr_decode(rqst);
374 		svc_freereq(rqst);
375 		goto out;
376 	}
377 
378 	if (nd.nd_repstat & NFSERR_AUTHERR) {
379 		svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
380 		if (nd.nd_mreq != NULL)
381 			m_freem(nd.nd_mreq);
382 	} else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) {
383 		svcerr_systemerr(rqst);
384 	}
385 	if (rp != NULL) {
386 		nfsrvd_sentcache(rp, (rqst->rq_reply_seq != 0 ||
387 		    SVC_ACK(xprt, NULL)), rqst->rq_reply_seq);
388 	}
389 	svc_freereq(rqst);
390 
391 out:
392 	free(nd.nd_principal, M_TEMP);
393 	NFSD_CURVNET_RESTORE();
394 	ast_kclear(curthread);
395 	NFSEXITCODE(0);
396 }
397 
398 /*
399  * Check the cache and, optionally, do the RPC.
400  * Return the appropriate cache response.
401  */
402 static int
403 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, SVCXPRT *xprt,
404     struct nfsrvcache **rpp)
405 {
406 	int cacherep = RC_DOIT, isdgram, taglen = -1;
407 	struct mbuf *m;
408 	u_char tag[NFSV4_SMALLSTR + 1], *tagstr = NULL;
409 	u_int32_t minorvers = 0;
410 	uint32_t ack;
411 
412 	*rpp = NULL;
413 	if (nd->nd_nam2 == NULL) {
414 		nd->nd_flag |= ND_STREAMSOCK;
415 		isdgram = 0;
416 	} else {
417 		isdgram = 1;
418 	}
419 
420 	/*
421 	 * Two cases:
422 	 * 1 - For NFSv2 over UDP, if we are near our malloc/mget
423 	 *     limit, just drop the request. There is no
424 	 *     NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the
425 	 *     client will timeout/retry over UDP in a little while.
426 	 * 2 - nd_repstat == 0 && nd_mreq == NULL, which
427 	 *     means a normal nfs rpc, so check the cache
428 	 */
429 	if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL &&
430 	    nfsrv_mallocmget_limit()) {
431 		cacherep = RC_DROPIT;
432 	} else {
433 		/*
434 		 * For NFSv3, play it safe and assume that the client is
435 		 * doing retries on the same TCP connection.
436 		 */
437 		if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) ==
438 		    ND_STREAMSOCK)
439 			nd->nd_flag |= ND_SAMETCPCONN;
440 		nd->nd_retxid = xid;
441 		nd->nd_tcpconntime = NFSD_MONOSEC;
442 		nd->nd_sockref = xprt->xp_sockref;
443 		if ((nd->nd_flag & ND_NFSV4) != 0)
444 			nfsd_getminorvers(nd, tag, &tagstr, &taglen,
445 			    &minorvers);
446 		if ((nd->nd_flag & ND_NFSV41) != 0)
447 			/* NFSv4.1 caches replies in the session slots. */
448 			cacherep = RC_DOIT;
449 		else {
450 			cacherep = nfsrvd_getcache(nd);
451 			ack = 0;
452 			SVC_ACK(xprt, &ack);
453 			nfsrc_trimcache(xprt->xp_sockref, ack, 0);
454 		}
455 	}
456 
457 	/*
458 	 * Handle the request. There are three cases.
459 	 * RC_DOIT - do the RPC
460 	 * RC_REPLY - return the reply already created
461 	 * RC_DROPIT - just throw the request away
462 	 */
463 	if (cacherep == RC_DOIT) {
464 		if ((nd->nd_flag & ND_NFSV41) != 0)
465 			nd->nd_xprt = xprt;
466 		nfsrvd_dorpc(nd, isdgram, tagstr, taglen, minorvers);
467 		if ((nd->nd_flag & ND_NFSV41) != 0) {
468 			if (nd->nd_repstat != NFSERR_REPLYFROMCACHE &&
469 			    (nd->nd_flag & ND_SAVEREPLY) != 0) {
470 				/* Cache a copy of the reply. */
471 				m = m_copym(nd->nd_mreq, 0, M_COPYALL,
472 				    M_WAITOK);
473 			} else
474 				m = NULL;
475 			if ((nd->nd_flag & ND_HASSEQUENCE) != 0)
476 				nfsrv_cache_session(nd, &m);
477 			if (nd->nd_repstat == NFSERR_REPLYFROMCACHE) {
478 				nd->nd_repstat = 0;
479 				if (m != NULL) {
480 					m_freem(nd->nd_mreq);
481 					nd->nd_mreq = m;
482 				}
483 			}
484 			cacherep = RC_REPLY;
485 		} else {
486 			if (nd->nd_repstat == NFSERR_DONTREPLY)
487 				cacherep = RC_DROPIT;
488 			else
489 				cacherep = RC_REPLY;
490 			*rpp = nfsrvd_updatecache(nd);
491 		}
492 	}
493 	if (tagstr != NULL && taglen > NFSV4_SMALLSTR)
494 		free(tagstr, M_TEMP);
495 
496 	NFSEXITCODE2(0, nd);
497 	return (cacherep);
498 }
499 
500 static void
501 nfssvc_loss(SVCXPRT *xprt)
502 {
503 	uint32_t ack;
504 
505 	ack = 0;
506 	SVC_ACK(xprt, &ack);
507 	NFSD_CURVNET_SET(NFSD_TD_TO_VNET(curthread));
508 	nfsrc_trimcache(xprt->xp_sockref, ack, 1);
509 	NFSD_CURVNET_RESTORE();
510 }
511 
512 /*
513  * Adds a socket to the list for servicing by nfsds.
514  */
515 int
516 nfsrvd_addsock(struct file *fp)
517 {
518 	int siz;
519 	struct socket *so;
520 	int error = 0;
521 	SVCXPRT *xprt;
522 	static u_int64_t sockref = 0;
523 
524 	so = fp->f_data;
525 
526 	siz = sb_max_adj;
527 	error = soreserve(so, siz, siz);
528 	if (error)
529 		goto out;
530 
531 	/*
532 	 * Steal the socket from userland so that it doesn't close
533 	 * unexpectedly.
534 	 */
535 	if (so->so_type == SOCK_DGRAM)
536 		xprt = svc_dg_create(NFSD_VNET(nfsrvd_pool), so, 0, 0);
537 	else
538 		xprt = svc_vc_create(NFSD_VNET(nfsrvd_pool), so, 0, 0);
539 	if (xprt) {
540 		fp->f_ops = &badfileops;
541 		fp->f_data = NULL;
542 		xprt->xp_sockref = ++sockref;
543 		if (NFSD_VNET(nfs_minvers) == NFS_VER2)
544 			svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program,
545 			    NULL);
546 		if (NFSD_VNET(nfs_minvers) <= NFS_VER3 &&
547 		    NFSD_VNET(nfs_maxvers) >= NFS_VER3)
548 			svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program,
549 			    NULL);
550 		if (NFSD_VNET(nfs_maxvers) >= NFS_VER4)
551 			svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program,
552 			    NULL);
553 		if (so->so_type == SOCK_STREAM)
554 			svc_loss_reg(xprt, nfssvc_loss);
555 		SVC_RELEASE(xprt);
556 	} else
557 		error = EPERM;
558 
559 out:
560 	NFSEXITCODE(error);
561 	return (error);
562 }
563 
564 /*
565  * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
566  * until it is killed by a signal.
567  */
568 int
569 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args)
570 {
571 	char principal[MAXHOSTNAMELEN + 5];
572 	struct proc *p;
573 	int error = 0;
574 	bool_t ret2, ret3, ret4;
575 
576 	error = copyinstr(args->principal, principal, sizeof (principal),
577 	    NULL);
578 	if (error)
579 		goto out;
580 
581 	/*
582 	 * Only the first nfsd actually does any work. The RPC code
583 	 * adds threads to it as needed. Any extra processes offered
584 	 * by nfsd just exit. If nfsd is new enough, it will call us
585 	 * once with a structure that specifies how many threads to
586 	 * use.
587 	 */
588 	NFSD_LOCK();
589 	if (NFSD_VNET(nfsrv_numnfsd) == 0) {
590 		nfsdev_time = time_second;
591 		p = td->td_proc;
592 		PROC_LOCK(p);
593 		p->p_flag2 |= P2_AST_SU;
594 		PROC_UNLOCK(p);
595 		newnfs_numnfsd++;	/* Total num for all vnets. */
596 		NFSD_VNET(nfsrv_numnfsd)++;	/* Num for this vnet. */
597 
598 		NFSD_UNLOCK();
599 		error = nfsrv_createdevids(args, td);
600 		if (error == 0) {
601 			/* An empty string implies AUTH_SYS only. */
602 			if (principal[0] != '\0') {
603 				ret2 = rpc_gss_set_svc_name_call(principal,
604 				    "kerberosv5", GSS_C_INDEFINITE, NFS_PROG,
605 				    NFS_VER2);
606 				ret3 = rpc_gss_set_svc_name_call(principal,
607 				    "kerberosv5", GSS_C_INDEFINITE, NFS_PROG,
608 				    NFS_VER3);
609 				ret4 = rpc_gss_set_svc_name_call(principal,
610 				    "kerberosv5", GSS_C_INDEFINITE, NFS_PROG,
611 				    NFS_VER4);
612 
613 				if (!ret2 || !ret3 || !ret4)
614 					printf("nfsd: can't register svc "
615 					    "name %s jid:%d\n", principal,
616 					    td->td_ucred->cr_prison->pr_id);
617 			}
618 
619 			NFSD_VNET(nfsrvd_pool)->sp_minthreads =
620 			    args->minthreads;
621 			NFSD_VNET(nfsrvd_pool)->sp_maxthreads =
622 			    args->maxthreads;
623 
624 			/*
625 			 * If this is a pNFS service, make Getattr do a
626 			 * vn_start_write(), so it can do a vn_set_extattr().
627 			 */
628 			if (nfsrv_devidcnt > 0) {
629 				nfsrv_writerpc[NFSPROC_GETATTR] = 1;
630 				nfsv4_opflag[NFSV4OP_GETATTR].modifyfs = 1;
631 			}
632 
633 			svc_run(NFSD_VNET(nfsrvd_pool));
634 
635 			/* Reset Getattr to not do a vn_start_write(). */
636 			nfsrv_writerpc[NFSPROC_GETATTR] = 0;
637 			nfsv4_opflag[NFSV4OP_GETATTR].modifyfs = 0;
638 
639 			if (principal[0] != '\0') {
640 				rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2);
641 				rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3);
642 				rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4);
643 			}
644 		}
645 		NFSD_LOCK();
646 		newnfs_numnfsd--;
647 		NFSD_VNET(nfsrv_numnfsd)--;
648 		nfsrvd_init(1);
649 		PROC_LOCK(p);
650 		p->p_flag2 &= ~P2_AST_SU;
651 		PROC_UNLOCK(p);
652 	}
653 	NFSD_UNLOCK();
654 
655 out:
656 	NFSEXITCODE(error);
657 	return (error);
658 }
659 
660 /*
661  * Initialize the data structures for the server.
662  * Handshake with any new nfsds starting up to avoid any chance of
663  * corruption.
664  */
665 void
666 nfsrvd_init(int terminating)
667 {
668 
669 	NFSD_LOCK_ASSERT();
670 
671 	if (terminating) {
672 		NFSD_VNET(nfsd_master_proc) = NULL;
673 		NFSD_UNLOCK();
674 		nfsrv_freealllayoutsanddevids();
675 		nfsrv_freeallbackchannel_xprts();
676 		svcpool_close(NFSD_VNET(nfsrvd_pool));
677 		free(nfsrv_zeropnfsdat, M_TEMP);
678 		nfsrv_zeropnfsdat = NULL;
679 		NFSD_LOCK();
680 	} else {
681 		/* Initialize per-vnet globals once per vnet. */
682 		if (NFSD_VNET(nfsrvd_inited))
683 			return;
684 		NFSD_VNET(nfsrvd_inited) = true;
685 		NFSD_UNLOCK();
686 		NFSD_VNET(nfsrvd_pool) = svcpool_create("nfsd",
687 		    SYSCTL_STATIC_CHILDREN(_vfs_nfsd));
688 		NFSD_VNET(nfsrvd_pool)->sp_rcache = NULL;
689 		NFSD_VNET(nfsrvd_pool)->sp_assign = fhanew_assign;
690 		NFSD_VNET(nfsrvd_pool)->sp_done = fhanew_nd_complete;
691 		NFSD_LOCK();
692 	}
693 }
694