xref: /trueos/sys/fs/nfsserver/nfs_nfsdkrpc.c (revision 4fc31a2c6b4c624186fb609e12be08ea94c20c1a)
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 <sys/param.h>
38 #include <sys/systm.h>
39 
40 #include "opt_inet6.h"
41 #include "opt_kgssapi.h"
42 
43 #include <fs/nfs/nfsport.h>
44 
45 #include <rpc/rpc.h>
46 #include <rpc/rpcsec_gss.h>
47 
48 #include <nfs/nfs_fha.h>
49 #include <fs/nfsserver/nfs_fha_new.h>
50 
51 #include <security/mac/mac_framework.h>
52 
53 NFSDLOCKMUTEX;
54 NFSV4ROOTLOCKMUTEX;
55 struct nfsv4lock nfsd_suspend_lock;
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 
86 SYSCTL_DECL(_vfs_nfsd);
87 
88 SVCPOOL		*nfsrvd_pool;
89 
90 static int	nfs_privport = 0;
91 SYSCTL_INT(_vfs_nfsd, OID_AUTO, nfs_privport, CTLFLAG_RWTUN,
92     &nfs_privport, 0,
93     "Only allow clients using a privileged port for NFSv2 and 3");
94 
95 static int	nfs_minvers = NFS_VER2;
96 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_min_nfsvers, CTLFLAG_RWTUN,
97     &nfs_minvers, 0, "The lowest version of NFS handled by the server");
98 
99 static int	nfs_maxvers = NFS_VER4;
100 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_max_nfsvers, CTLFLAG_RWTUN,
101     &nfs_maxvers, 0, "The highest version of NFS handled by the server");
102 
103 static int nfs_proc(struct nfsrv_descript *, u_int32_t, SVCXPRT *xprt,
104     struct nfsrvcache **);
105 
106 extern u_long sb_max_adj;
107 extern int newnfs_numnfsd;
108 extern struct proc *nfsd_master_proc;
109 
110 /*
111  * NFS server system calls
112  */
113 
114 static void
nfssvc_program(struct svc_req * rqst,SVCXPRT * xprt)115 nfssvc_program(struct svc_req *rqst, SVCXPRT *xprt)
116 {
117 	struct nfsrv_descript nd;
118 	struct nfsrvcache *rp = NULL;
119 	int cacherep, credflavor;
120 
121 	memset(&nd, 0, sizeof(nd));
122 	if (rqst->rq_vers == NFS_VER2) {
123 		if (rqst->rq_proc > NFSV2PROC_STATFS ||
124 		    newnfs_nfsv3_procid[rqst->rq_proc] == NFSPROC_NOOP) {
125 			svcerr_noproc(rqst);
126 			svc_freereq(rqst);
127 			goto out;
128 		}
129 		nd.nd_procnum = newnfs_nfsv3_procid[rqst->rq_proc];
130 		nd.nd_flag = ND_NFSV2;
131 	} else if (rqst->rq_vers == NFS_VER3) {
132 		if (rqst->rq_proc >= NFS_V3NPROCS) {
133 			svcerr_noproc(rqst);
134 			svc_freereq(rqst);
135 			goto out;
136 		}
137 		nd.nd_procnum = rqst->rq_proc;
138 		nd.nd_flag = ND_NFSV3;
139 	} else {
140 		if (rqst->rq_proc != NFSPROC_NULL &&
141 		    rqst->rq_proc != NFSV4PROC_COMPOUND) {
142 			svcerr_noproc(rqst);
143 			svc_freereq(rqst);
144 			goto out;
145 		}
146 		nd.nd_procnum = rqst->rq_proc;
147 		nd.nd_flag = ND_NFSV4;
148 	}
149 
150 	/*
151 	 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 -
152 	 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP
153 	 * mounts.
154 	 */
155 	nd.nd_mrep = rqst->rq_args;
156 	rqst->rq_args = NULL;
157 	newnfs_realign(&nd.nd_mrep, M_WAITOK);
158 	nd.nd_md = nd.nd_mrep;
159 	nd.nd_dpos = mtod(nd.nd_md, caddr_t);
160 	nd.nd_nam = svc_getrpccaller(rqst);
161 	nd.nd_nam2 = rqst->rq_addr;
162 	nd.nd_mreq = NULL;
163 	nd.nd_cred = NULL;
164 
165 	if (nfs_privport && (nd.nd_flag & ND_NFSV4) == 0) {
166 		/* Check if source port is privileged */
167 		u_short port;
168 		struct sockaddr *nam = nd.nd_nam;
169 		struct sockaddr_in *sin;
170 
171 		sin = (struct sockaddr_in *)nam;
172 		/*
173 		 * INET/INET6 - same code:
174 		 *    sin_port and sin6_port are at same offset
175 		 */
176 		port = ntohs(sin->sin_port);
177 		if (port >= IPPORT_RESERVED &&
178 		    nd.nd_procnum != NFSPROC_NULL) {
179 #ifdef INET6
180 			char b6[INET6_ADDRSTRLEN];
181 #if defined(KLD_MODULE)
182 			/* Do not use ip6_sprintf: the nfs module should work without INET6. */
183 #define	ip6_sprintf(buf, a)						\
184 			(sprintf((buf), "%x:%x:%x:%x:%x:%x:%x:%x",	\
185 			    (a)->s6_addr16[0], (a)->s6_addr16[1],	\
186 			    (a)->s6_addr16[2], (a)->s6_addr16[3],	\
187 			    (a)->s6_addr16[4], (a)->s6_addr16[5],	\
188 			    (a)->s6_addr16[6], (a)->s6_addr16[7]),	\
189 			    (buf))
190 #endif
191 #endif
192 			printf("NFS request from unprivileged port (%s:%d)\n",
193 #ifdef INET6
194 			    sin->sin_family == AF_INET6 ?
195 			    ip6_sprintf(b6, &satosin6(sin)->sin6_addr) :
196 #if defined(KLD_MODULE)
197 #undef ip6_sprintf
198 #endif
199 #endif
200 			    inet_ntoa(sin->sin_addr), port);
201 			svcerr_weakauth(rqst);
202 			svc_freereq(rqst);
203 			m_freem(nd.nd_mrep);
204 			goto out;
205 		}
206 	}
207 
208 	if (nd.nd_procnum != NFSPROC_NULL) {
209 		if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) {
210 			svcerr_weakauth(rqst);
211 			svc_freereq(rqst);
212 			m_freem(nd.nd_mrep);
213 			goto out;
214 		}
215 
216 		/* Set the flag based on credflavor */
217 		if (credflavor == RPCSEC_GSS_KRB5) {
218 			nd.nd_flag |= ND_GSS;
219 		} else if (credflavor == RPCSEC_GSS_KRB5I) {
220 			nd.nd_flag |= (ND_GSS | ND_GSSINTEGRITY);
221 		} else if (credflavor == RPCSEC_GSS_KRB5P) {
222 			nd.nd_flag |= (ND_GSS | ND_GSSPRIVACY);
223 		} else if (credflavor != AUTH_SYS) {
224 			svcerr_weakauth(rqst);
225 			svc_freereq(rqst);
226 			m_freem(nd.nd_mrep);
227 			goto out;
228 		}
229 
230 #ifdef MAC
231 		mac_cred_associate_nfsd(nd.nd_cred);
232 #endif
233 		/*
234 		 * Get a refcnt (shared lock) on nfsd_suspend_lock.
235 		 * NFSSVC_SUSPENDNFSD will take an exclusive lock on
236 		 * nfsd_suspend_lock to suspend these threads.
237 		 * This must be done here, before the check of
238 		 * nfsv4root exports by nfsvno_v4rootexport().
239 		 */
240 		NFSLOCKV4ROOTMUTEX();
241 		nfsv4_getref(&nfsd_suspend_lock, NULL, NFSV4ROOTLOCKMUTEXPTR,
242 		    NULL);
243 		NFSUNLOCKV4ROOTMUTEX();
244 
245 		if ((nd.nd_flag & ND_NFSV4) != 0) {
246 			nd.nd_repstat = nfsvno_v4rootexport(&nd);
247 			if (nd.nd_repstat != 0) {
248 				NFSLOCKV4ROOTMUTEX();
249 				nfsv4_relref(&nfsd_suspend_lock);
250 				NFSUNLOCKV4ROOTMUTEX();
251 				svcerr_weakauth(rqst);
252 				svc_freereq(rqst);
253 				m_freem(nd.nd_mrep);
254 				goto out;
255 			}
256 		}
257 
258 		cacherep = nfs_proc(&nd, rqst->rq_xid, xprt, &rp);
259 		NFSLOCKV4ROOTMUTEX();
260 		nfsv4_relref(&nfsd_suspend_lock);
261 		NFSUNLOCKV4ROOTMUTEX();
262 	} else {
263 		NFSMGET(nd.nd_mreq);
264 		nd.nd_mreq->m_len = 0;
265 		cacherep = RC_REPLY;
266 	}
267 	if (nd.nd_mrep != NULL)
268 		m_freem(nd.nd_mrep);
269 
270 	if (nd.nd_cred != NULL)
271 		crfree(nd.nd_cred);
272 
273 	if (cacherep == RC_DROPIT) {
274 		if (nd.nd_mreq != NULL)
275 			m_freem(nd.nd_mreq);
276 		svc_freereq(rqst);
277 		goto out;
278 	}
279 
280 	if (nd.nd_mreq == NULL) {
281 		svcerr_decode(rqst);
282 		svc_freereq(rqst);
283 		goto out;
284 	}
285 
286 	if (nd.nd_repstat & NFSERR_AUTHERR) {
287 		svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
288 		if (nd.nd_mreq != NULL)
289 			m_freem(nd.nd_mreq);
290 	} else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) {
291 		svcerr_systemerr(rqst);
292 	}
293 	if (rp != NULL) {
294 		nfsrvd_sentcache(rp, (rqst->rq_reply_seq != 0 ||
295 		    SVC_ACK(xprt, NULL)), rqst->rq_reply_seq);
296 	}
297 	svc_freereq(rqst);
298 
299 out:
300 	if (softdep_ast_cleanup != NULL)
301 		softdep_ast_cleanup();
302 	NFSEXITCODE(0);
303 }
304 
305 /*
306  * Check the cache and, optionally, do the RPC.
307  * Return the appropriate cache response.
308  */
309 static int
nfs_proc(struct nfsrv_descript * nd,u_int32_t xid,SVCXPRT * xprt,struct nfsrvcache ** rpp)310 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, SVCXPRT *xprt,
311     struct nfsrvcache **rpp)
312 {
313 	struct thread *td = curthread;
314 	int cacherep = RC_DOIT, isdgram, taglen = -1;
315 	struct mbuf *m;
316 	u_char tag[NFSV4_SMALLSTR + 1], *tagstr = NULL;
317 	u_int32_t minorvers = 0;
318 	uint32_t ack;
319 
320 	*rpp = NULL;
321 	if (nd->nd_nam2 == NULL) {
322 		nd->nd_flag |= ND_STREAMSOCK;
323 		isdgram = 0;
324 	} else {
325 		isdgram = 1;
326 	}
327 
328 	/*
329 	 * Two cases:
330 	 * 1 - For NFSv2 over UDP, if we are near our malloc/mget
331 	 *     limit, just drop the request. There is no
332 	 *     NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the
333 	 *     client will timeout/retry over UDP in a little while.
334 	 * 2 - nd_repstat == 0 && nd_mreq == NULL, which
335 	 *     means a normal nfs rpc, so check the cache
336 	 */
337 	if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL &&
338 	    nfsrv_mallocmget_limit()) {
339 		cacherep = RC_DROPIT;
340 	} else {
341 		/*
342 		 * For NFSv3, play it safe and assume that the client is
343 		 * doing retries on the same TCP connection.
344 		 */
345 		if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) ==
346 		    ND_STREAMSOCK)
347 			nd->nd_flag |= ND_SAMETCPCONN;
348 		nd->nd_retxid = xid;
349 		nd->nd_tcpconntime = NFSD_MONOSEC;
350 		nd->nd_sockref = xprt->xp_sockref;
351 		if ((nd->nd_flag & ND_NFSV4) != 0)
352 			nfsd_getminorvers(nd, tag, &tagstr, &taglen,
353 			    &minorvers);
354 		if ((nd->nd_flag & ND_NFSV41) != 0)
355 			/* NFSv4.1 caches replies in the session slots. */
356 			cacherep = RC_DOIT;
357 		else {
358 			cacherep = nfsrvd_getcache(nd);
359 			ack = 0;
360 			SVC_ACK(xprt, &ack);
361 			nfsrc_trimcache(xprt->xp_sockref, ack, 0);
362 		}
363 	}
364 
365 	/*
366 	 * Handle the request. There are three cases.
367 	 * RC_DOIT - do the RPC
368 	 * RC_REPLY - return the reply already created
369 	 * RC_DROPIT - just throw the request away
370 	 */
371 	if (cacherep == RC_DOIT) {
372 		if ((nd->nd_flag & ND_NFSV41) != 0)
373 			nd->nd_xprt = xprt;
374 		nfsrvd_dorpc(nd, isdgram, tagstr, taglen, minorvers, td);
375 		if ((nd->nd_flag & ND_NFSV41) != 0) {
376 			if (nd->nd_repstat != NFSERR_REPLYFROMCACHE &&
377 			    (nd->nd_flag & ND_SAVEREPLY) != 0) {
378 				/* Cache a copy of the reply. */
379 				m = m_copym(nd->nd_mreq, 0, M_COPYALL,
380 				    M_WAITOK);
381 			} else
382 				m = NULL;
383 			if ((nd->nd_flag & ND_HASSEQUENCE) != 0)
384 				nfsrv_cache_session(nd->nd_sessionid,
385 				    nd->nd_slotid, nd->nd_repstat, &m);
386 			if (nd->nd_repstat == NFSERR_REPLYFROMCACHE)
387 				nd->nd_repstat = 0;
388 			cacherep = RC_REPLY;
389 		} else {
390 			if (nd->nd_repstat == NFSERR_DONTREPLY)
391 				cacherep = RC_DROPIT;
392 			else
393 				cacherep = RC_REPLY;
394 			*rpp = nfsrvd_updatecache(nd);
395 		}
396 	}
397 	if (tagstr != NULL && taglen > NFSV4_SMALLSTR)
398 		free(tagstr, M_TEMP);
399 
400 	NFSEXITCODE2(0, nd);
401 	return (cacherep);
402 }
403 
404 static void
nfssvc_loss(SVCXPRT * xprt)405 nfssvc_loss(SVCXPRT *xprt)
406 {
407 	uint32_t ack;
408 
409 	ack = 0;
410 	SVC_ACK(xprt, &ack);
411 	nfsrc_trimcache(xprt->xp_sockref, ack, 1);
412 }
413 
414 /*
415  * Adds a socket to the list for servicing by nfsds.
416  */
417 int
nfsrvd_addsock(struct file * fp)418 nfsrvd_addsock(struct file *fp)
419 {
420 	int siz;
421 	struct socket *so;
422 	int error = 0;
423 	SVCXPRT *xprt;
424 	static u_int64_t sockref = 0;
425 
426 	so = fp->f_data;
427 
428 	siz = sb_max_adj;
429 	error = soreserve(so, siz, siz);
430 	if (error)
431 		goto out;
432 
433 	/*
434 	 * Steal the socket from userland so that it doesn't close
435 	 * unexpectedly.
436 	 */
437 	if (so->so_type == SOCK_DGRAM)
438 		xprt = svc_dg_create(nfsrvd_pool, so, 0, 0);
439 	else
440 		xprt = svc_vc_create(nfsrvd_pool, so, 0, 0);
441 	if (xprt) {
442 		fp->f_ops = &badfileops;
443 		fp->f_data = NULL;
444 		xprt->xp_sockref = ++sockref;
445 		if (nfs_minvers == NFS_VER2)
446 			svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program,
447 			    NULL);
448 		if (nfs_minvers <= NFS_VER3 && nfs_maxvers >= NFS_VER3)
449 			svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program,
450 			    NULL);
451 		if (nfs_maxvers >= NFS_VER4)
452 			svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program,
453 			    NULL);
454 		if (so->so_type == SOCK_STREAM)
455 			svc_loss_reg(xprt, nfssvc_loss);
456 		SVC_RELEASE(xprt);
457 	}
458 
459 out:
460 	NFSEXITCODE(error);
461 	return (error);
462 }
463 
464 /*
465  * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
466  * until it is killed by a signal.
467  */
468 int
nfsrvd_nfsd(struct thread * td,struct nfsd_nfsd_args * args)469 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args)
470 {
471 	char principal[MAXHOSTNAMELEN + 5];
472 	struct proc *p;
473 	int error = 0;
474 	bool_t ret2, ret3, ret4;
475 
476 	error = copyinstr(args->principal, principal, sizeof (principal),
477 	    NULL);
478 	if (error)
479 		goto out;
480 
481 	/*
482 	 * Only the first nfsd actually does any work. The RPC code
483 	 * adds threads to it as needed. Any extra processes offered
484 	 * by nfsd just exit. If nfsd is new enough, it will call us
485 	 * once with a structure that specifies how many threads to
486 	 * use.
487 	 */
488 	NFSD_LOCK();
489 	if (newnfs_numnfsd == 0) {
490 		p = td->td_proc;
491 		PROC_LOCK(p);
492 		p->p_flag2 |= P2_AST_SU;
493 		PROC_UNLOCK(p);
494 		newnfs_numnfsd++;
495 
496 		NFSD_UNLOCK();
497 
498 		/* An empty string implies AUTH_SYS only. */
499 		if (principal[0] != '\0') {
500 			ret2 = rpc_gss_set_svc_name_call(principal,
501 			    "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER2);
502 			ret3 = rpc_gss_set_svc_name_call(principal,
503 			    "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER3);
504 			ret4 = rpc_gss_set_svc_name_call(principal,
505 			    "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER4);
506 
507 			if (!ret2 || !ret3 || !ret4)
508 				printf("nfsd: can't register svc name\n");
509 		}
510 
511 		nfsrvd_pool->sp_minthreads = args->minthreads;
512 		nfsrvd_pool->sp_maxthreads = args->maxthreads;
513 
514 		svc_run(nfsrvd_pool);
515 
516 		if (principal[0] != '\0') {
517 			rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2);
518 			rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3);
519 			rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4);
520 		}
521 
522 		NFSD_LOCK();
523 		newnfs_numnfsd--;
524 		nfsrvd_init(1);
525 		PROC_LOCK(p);
526 		p->p_flag2 &= ~P2_AST_SU;
527 		PROC_UNLOCK(p);
528 	}
529 	NFSD_UNLOCK();
530 
531 out:
532 	NFSEXITCODE(error);
533 	return (error);
534 }
535 
536 /*
537  * Initialize the data structures for the server.
538  * Handshake with any new nfsds starting up to avoid any chance of
539  * corruption.
540  */
541 void
nfsrvd_init(int terminating)542 nfsrvd_init(int terminating)
543 {
544 
545 	NFSD_LOCK_ASSERT();
546 
547 	if (terminating) {
548 		nfsd_master_proc = NULL;
549 		NFSD_UNLOCK();
550 		svcpool_destroy(nfsrvd_pool);
551 		nfsrvd_pool = NULL;
552 		NFSD_LOCK();
553 	}
554 
555 	NFSD_UNLOCK();
556 
557 	nfsrvd_pool = svcpool_create("nfsd", SYSCTL_STATIC_CHILDREN(_vfs_nfsd));
558 	nfsrvd_pool->sp_rcache = NULL;
559 	nfsrvd_pool->sp_assign = fhanew_assign;
560 	nfsrvd_pool->sp_done = fha_nd_complete;
561 
562 	NFSD_LOCK();
563 }
564 
565