1 /* $NetBSD: nfs_nfsdkrpc.c,v 1.4 2016/12/13 21:50:32 pgoyette Exp $ */
2 /*-
3 * Copyright (c) 1989, 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Rick Macklem at The University of Guelph.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 */
34
35 #include <sys/cdefs.h>
36 /* __FBSDID("FreeBSD: head/sys/fs/nfsserver/nfs_nfsdkrpc.c 299203 2016-05-06 23:40:37Z pfg "); */
37 __RCSID("$NetBSD: nfs_nfsdkrpc.c,v 1.4 2016/12/13 21:50:32 pgoyette Exp $");
38
39 #ifdef _KERNEL_OPT
40 #include "opt_inet6.h"
41 #if 0
42 #include "opt_kgssapi.h"
43 #endif
44 #endif
45
46 #include <fs/nfs/common/nfsport.h>
47
48 #include <rpc/rpc.h>
49 #include <rpc/rpcsec_gss.h>
50
51 #include <fs/nfs/common/nfs_fha.h>
52 #include <fs/nfs/server/nfs_fha_new.h>
53
54 #if 0
55 #include <security/mac/mac_framework.h>
56 #endif
57
58 NFSDLOCKMUTEX;
59 NFSV4ROOTLOCKMUTEX;
60 struct nfsv4lock nfsd_suspend_lock;
61
62 /*
63 * Mapping of old NFS Version 2 RPC numbers to generic numbers.
64 */
65 int newnfs_nfsv3_procid[NFS_V3NPROCS] = {
66 NFSPROC_NULL,
67 NFSPROC_GETATTR,
68 NFSPROC_SETATTR,
69 NFSPROC_NOOP,
70 NFSPROC_LOOKUP,
71 NFSPROC_READLINK,
72 NFSPROC_READ,
73 NFSPROC_NOOP,
74 NFSPROC_WRITE,
75 NFSPROC_CREATE,
76 NFSPROC_REMOVE,
77 NFSPROC_RENAME,
78 NFSPROC_LINK,
79 NFSPROC_SYMLINK,
80 NFSPROC_MKDIR,
81 NFSPROC_RMDIR,
82 NFSPROC_READDIR,
83 NFSPROC_FSSTAT,
84 NFSPROC_NOOP,
85 NFSPROC_NOOP,
86 NFSPROC_NOOP,
87 NFSPROC_NOOP,
88 };
89
90
91 SYSCTL_DECL(_vfs_nfsd);
92
93 SVCPOOL *nfsrvd_pool;
94
95 static int nfs_privport = 0;
96 SYSCTL_INT(_vfs_nfsd, OID_AUTO, nfs_privport, CTLFLAG_RWTUN,
97 &nfs_privport, 0,
98 "Only allow clients using a privileged port for NFSv2 and 3");
99
100 static int nfs_minvers = NFS_VER2;
101 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_min_nfsvers, CTLFLAG_RWTUN,
102 &nfs_minvers, 0, "The lowest version of NFS handled by the server");
103
104 static int nfs_maxvers = NFS_VER4;
105 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_max_nfsvers, CTLFLAG_RWTUN,
106 &nfs_maxvers, 0, "The highest version of NFS handled by the server");
107
108 static int nfs_proc(struct nfsrv_descript *, u_int32_t, SVCXPRT *xprt,
109 struct nfsrvcache **);
110
111 extern u_long sb_max_adj;
112 extern int newnfs_numnfsd;
113 extern struct proc *nfsd_master_proc;
114
115 /*
116 * NFS server system calls
117 */
118
119 static void
nfssvc_program(struct svc_req * rqst,SVCXPRT * xprt)120 nfssvc_program(struct svc_req *rqst, SVCXPRT *xprt)
121 {
122 struct nfsrv_descript nd;
123 struct nfsrvcache *rp = NULL;
124 int cacherep, credflavor;
125
126 memset(&nd, 0, sizeof(nd));
127 if (rqst->rq_vers == NFS_VER2) {
128 if (rqst->rq_proc > NFSV2PROC_STATFS ||
129 newnfs_nfsv3_procid[rqst->rq_proc] == NFSPROC_NOOP) {
130 svcerr_noproc(rqst);
131 svc_freereq(rqst);
132 goto out;
133 }
134 nd.nd_procnum = newnfs_nfsv3_procid[rqst->rq_proc];
135 nd.nd_flag = ND_NFSV2;
136 } else if (rqst->rq_vers == NFS_VER3) {
137 if (rqst->rq_proc >= NFS_V3NPROCS) {
138 svcerr_noproc(rqst);
139 svc_freereq(rqst);
140 goto out;
141 }
142 nd.nd_procnum = rqst->rq_proc;
143 nd.nd_flag = ND_NFSV3;
144 } else {
145 if (rqst->rq_proc != NFSPROC_NULL &&
146 rqst->rq_proc != NFSV4PROC_COMPOUND) {
147 svcerr_noproc(rqst);
148 svc_freereq(rqst);
149 goto out;
150 }
151 nd.nd_procnum = rqst->rq_proc;
152 nd.nd_flag = ND_NFSV4;
153 }
154
155 /*
156 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 -
157 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP
158 * mounts.
159 */
160 nd.nd_mrep = rqst->rq_args;
161 rqst->rq_args = NULL;
162 newnfs_realign(&nd.nd_mrep, M_WAITOK);
163 nd.nd_md = nd.nd_mrep;
164 nd.nd_dpos = mtod(nd.nd_md, caddr_t);
165 nd.nd_nam = svc_getrpccaller(rqst);
166 nd.nd_nam2 = rqst->rq_addr;
167 nd.nd_mreq = NULL;
168 nd.nd_cred = NULL;
169
170 if (nfs_privport && (nd.nd_flag & ND_NFSV4) == 0) {
171 /* Check if source port is privileged */
172 u_short port;
173 struct sockaddr *nam = nd.nd_nam;
174 struct sockaddr_in *sin;
175
176 sin = (struct sockaddr_in *)nam;
177 /*
178 * INET/INET6 - same code:
179 * sin_port and sin6_port are at same offset
180 */
181 port = ntohs(sin->sin_port);
182 if (port >= IPPORT_RESERVED &&
183 nd.nd_procnum != NFSPROC_NULL) {
184 #ifdef INET6
185 char b6[INET6_ADDRSTRLEN];
186 #if defined(_MODULE)
187 /* Do not use ip6_sprintf: the nfs module should work without INET6. */
188 #define ip6_sprintf(buf, a) \
189 (snprintf((buf), sizeof(buf), "%x:%x:%x:%x:%x:%x:%x:%x", \
190 (a)->s6_addr16[0], (a)->s6_addr16[1], \
191 (a)->s6_addr16[2], (a)->s6_addr16[3], \
192 (a)->s6_addr16[4], (a)->s6_addr16[5], \
193 (a)->s6_addr16[6], (a)->s6_addr16[7]), \
194 (buf))
195 #endif
196 #endif
197 printf("NFS request from unprivileged port (%s:%d)\n",
198 #ifdef INET6
199 sin->sin_family == AF_INET6 ?
200 ip6_sprintf(b6, &satosin6(sin)->sin6_addr) :
201 #if defined(_MODULE)
202 #undef ip6_sprintf
203 #endif
204 #endif
205 inet_ntoa(sin->sin_addr), port);
206 svcerr_weakauth(rqst);
207 svc_freereq(rqst);
208 m_freem(nd.nd_mrep);
209 goto out;
210 }
211 }
212
213 if (nd.nd_procnum != NFSPROC_NULL) {
214 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) {
215 svcerr_weakauth(rqst);
216 svc_freereq(rqst);
217 m_freem(nd.nd_mrep);
218 goto out;
219 }
220
221 /* Set the flag based on credflavor */
222 if (credflavor == RPCSEC_GSS_KRB5) {
223 nd.nd_flag |= ND_GSS;
224 } else if (credflavor == RPCSEC_GSS_KRB5I) {
225 nd.nd_flag |= (ND_GSS | ND_GSSINTEGRITY);
226 } else if (credflavor == RPCSEC_GSS_KRB5P) {
227 nd.nd_flag |= (ND_GSS | ND_GSSPRIVACY);
228 } else if (credflavor != AUTH_SYS) {
229 svcerr_weakauth(rqst);
230 svc_freereq(rqst);
231 m_freem(nd.nd_mrep);
232 goto out;
233 }
234
235 #ifdef MAC
236 mac_cred_associate_nfsd(nd.nd_cred);
237 #endif
238 /*
239 * Get a refcnt (shared lock) on nfsd_suspend_lock.
240 * NFSSVC_SUSPENDNFSD will take an exclusive lock on
241 * nfsd_suspend_lock to suspend these threads.
242 * The call to nfsv4_lock() that precedes nfsv4_getref()
243 * ensures that the acquisition of the exclusive lock
244 * takes priority over acquisition of the shared lock by
245 * waiting for any exclusive lock request to complete.
246 * This must be done here, before the check of
247 * nfsv4root exports by nfsvno_v4rootexport().
248 */
249 NFSLOCKV4ROOTMUTEX();
250 nfsv4_lock(&nfsd_suspend_lock, 0, NULL, NFSV4ROOTLOCKMUTEXPTR,
251 NULL);
252 nfsv4_getref(&nfsd_suspend_lock, NULL, NFSV4ROOTLOCKMUTEXPTR,
253 NULL);
254 NFSUNLOCKV4ROOTMUTEX();
255
256 if ((nd.nd_flag & ND_NFSV4) != 0) {
257 nd.nd_repstat = nfsvno_v4rootexport(&nd);
258 if (nd.nd_repstat != 0) {
259 NFSLOCKV4ROOTMUTEX();
260 nfsv4_relref(&nfsd_suspend_lock);
261 NFSUNLOCKV4ROOTMUTEX();
262 svcerr_weakauth(rqst);
263 svc_freereq(rqst);
264 m_freem(nd.nd_mrep);
265 goto out;
266 }
267 }
268
269 cacherep = nfs_proc(&nd, rqst->rq_xid, xprt, &rp);
270 NFSLOCKV4ROOTMUTEX();
271 nfsv4_relref(&nfsd_suspend_lock);
272 NFSUNLOCKV4ROOTMUTEX();
273 } else {
274 NFSMGET(nd.nd_mreq);
275 nd.nd_mreq->m_len = 0;
276 cacherep = RC_REPLY;
277 }
278 if (nd.nd_mrep != NULL)
279 m_freem(nd.nd_mrep);
280
281 if (nd.nd_cred != NULL)
282 crfree(nd.nd_cred);
283
284 if (cacherep == RC_DROPIT) {
285 if (nd.nd_mreq != NULL)
286 m_freem(nd.nd_mreq);
287 svc_freereq(rqst);
288 goto out;
289 }
290
291 if (nd.nd_mreq == NULL) {
292 svcerr_decode(rqst);
293 svc_freereq(rqst);
294 goto out;
295 }
296
297 if (nd.nd_repstat & NFSERR_AUTHERR) {
298 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
299 if (nd.nd_mreq != NULL)
300 m_freem(nd.nd_mreq);
301 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) {
302 svcerr_systemerr(rqst);
303 }
304 if (rp != NULL) {
305 nfsrvd_sentcache(rp, (rqst->rq_reply_seq != 0 ||
306 SVC_ACK(xprt, NULL)), rqst->rq_reply_seq);
307 }
308 svc_freereq(rqst);
309
310 out:
311 if (softdep_ast_cleanup != NULL)
312 softdep_ast_cleanup();
313 NFSEXITCODE(0);
314 }
315
316 /*
317 * Check the cache and, optionally, do the RPC.
318 * Return the appropriate cache response.
319 */
320 static int
nfs_proc(struct nfsrv_descript * nd,u_int32_t xid,SVCXPRT * xprt,struct nfsrvcache ** rpp)321 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, SVCXPRT *xprt,
322 struct nfsrvcache **rpp)
323 {
324 struct thread *td = curthread;
325 int cacherep = RC_DOIT, isdgram, taglen = -1;
326 struct mbuf *m;
327 u_char tag[NFSV4_SMALLSTR + 1], *tagstr = NULL;
328 u_int32_t minorvers = 0;
329 uint32_t ack;
330
331 *rpp = NULL;
332 if (nd->nd_nam2 == NULL) {
333 nd->nd_flag |= ND_STREAMSOCK;
334 isdgram = 0;
335 } else {
336 isdgram = 1;
337 }
338
339 /*
340 * Two cases:
341 * 1 - For NFSv2 over UDP, if we are near our malloc/mget
342 * limit, just drop the request. There is no
343 * NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the
344 * client will timeout/retry over UDP in a little while.
345 * 2 - nd_repstat == 0 && nd_mreq == NULL, which
346 * means a normal nfs rpc, so check the cache
347 */
348 if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL &&
349 nfsrv_mallocmget_limit()) {
350 cacherep = RC_DROPIT;
351 } else {
352 /*
353 * For NFSv3, play it safe and assume that the client is
354 * doing retries on the same TCP connection.
355 */
356 if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) ==
357 ND_STREAMSOCK)
358 nd->nd_flag |= ND_SAMETCPCONN;
359 nd->nd_retxid = xid;
360 nd->nd_tcpconntime = NFSD_MONOSEC;
361 nd->nd_sockref = xprt->xp_sockref;
362 if ((nd->nd_flag & ND_NFSV4) != 0)
363 nfsd_getminorvers(nd, tag, &tagstr, &taglen,
364 &minorvers);
365 if ((nd->nd_flag & ND_NFSV41) != 0)
366 /* NFSv4.1 caches replies in the session slots. */
367 cacherep = RC_DOIT;
368 else {
369 cacherep = nfsrvd_getcache(nd);
370 ack = 0;
371 SVC_ACK(xprt, &ack);
372 nfsrc_trimcache(xprt->xp_sockref, ack, 0);
373 }
374 }
375
376 /*
377 * Handle the request. There are three cases.
378 * RC_DOIT - do the RPC
379 * RC_REPLY - return the reply already created
380 * RC_DROPIT - just throw the request away
381 */
382 if (cacherep == RC_DOIT) {
383 if ((nd->nd_flag & ND_NFSV41) != 0)
384 nd->nd_xprt = xprt;
385 nfsrvd_dorpc(nd, isdgram, tagstr, taglen, minorvers, td);
386 if ((nd->nd_flag & ND_NFSV41) != 0) {
387 if (nd->nd_repstat != NFSERR_REPLYFROMCACHE &&
388 (nd->nd_flag & ND_SAVEREPLY) != 0) {
389 /* Cache a copy of the reply. */
390 m = m_copym(nd->nd_mreq, 0, M_COPYALL,
391 M_WAITOK);
392 } else
393 m = NULL;
394 if ((nd->nd_flag & ND_HASSEQUENCE) != 0)
395 nfsrv_cache_session(nd->nd_sessionid,
396 nd->nd_slotid, nd->nd_repstat, &m);
397 if (nd->nd_repstat == NFSERR_REPLYFROMCACHE)
398 nd->nd_repstat = 0;
399 cacherep = RC_REPLY;
400 } else {
401 if (nd->nd_repstat == NFSERR_DONTREPLY)
402 cacherep = RC_DROPIT;
403 else
404 cacherep = RC_REPLY;
405 *rpp = nfsrvd_updatecache(nd);
406 }
407 }
408 if (tagstr != NULL && taglen > NFSV4_SMALLSTR)
409 free(tagstr, M_TEMP);
410
411 NFSEXITCODE2(0, nd);
412 return (cacherep);
413 }
414
415 static void
nfssvc_loss(SVCXPRT * xprt)416 nfssvc_loss(SVCXPRT *xprt)
417 {
418 uint32_t ack;
419
420 ack = 0;
421 SVC_ACK(xprt, &ack);
422 nfsrc_trimcache(xprt->xp_sockref, ack, 1);
423 }
424
425 /*
426 * Adds a socket to the list for servicing by nfsds.
427 */
428 int
nfsrvd_addsock(struct file * fp)429 nfsrvd_addsock(struct file *fp)
430 {
431 int siz;
432 struct socket *so;
433 int error = 0;
434 SVCXPRT *xprt;
435 static u_int64_t sockref = 0;
436
437 so = fp->f_data;
438
439 siz = sb_max_adj;
440 error = soreserve(so, siz, siz);
441 if (error)
442 goto out;
443
444 /*
445 * Steal the socket from userland so that it doesn't close
446 * unexpectedly.
447 */
448 if (so->so_type == SOCK_DGRAM)
449 xprt = svc_dg_create(nfsrvd_pool, so, 0, 0);
450 else
451 xprt = svc_vc_create(nfsrvd_pool, so, 0, 0);
452 if (xprt) {
453 fp->f_ops = &badfileops;
454 fp->f_data = NULL;
455 xprt->xp_sockref = ++sockref;
456 if (nfs_minvers == NFS_VER2)
457 svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program,
458 NULL);
459 if (nfs_minvers <= NFS_VER3 && nfs_maxvers >= NFS_VER3)
460 svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program,
461 NULL);
462 if (nfs_maxvers >= NFS_VER4)
463 svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program,
464 NULL);
465 if (so->so_type == SOCK_STREAM)
466 svc_loss_reg(xprt, nfssvc_loss);
467 SVC_RELEASE(xprt);
468 }
469
470 out:
471 NFSEXITCODE(error);
472 return (error);
473 }
474
475 /*
476 * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
477 * until it is killed by a signal.
478 */
479 int
nfsrvd_nfsd(struct thread * td,struct nfsd_nfsd_args * args)480 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args)
481 {
482 char principal[MAXHOSTNAMELEN + 5];
483 struct proc *p;
484 int error = 0;
485 bool_t ret2, ret3, ret4;
486
487 error = copyinstr(args->principal, principal, sizeof (principal),
488 NULL);
489 if (error)
490 goto out;
491
492 /*
493 * Only the first nfsd actually does any work. The RPC code
494 * adds threads to it as needed. Any extra processes offered
495 * by nfsd just exit. If nfsd is new enough, it will call us
496 * once with a structure that specifies how many threads to
497 * use.
498 */
499 NFSD_LOCK();
500 if (newnfs_numnfsd == 0) {
501 p = td->td_proc;
502 PROC_LOCK(p);
503 p->p_flag2 |= P2_AST_SU;
504 PROC_UNLOCK(p);
505 newnfs_numnfsd++;
506
507 NFSD_UNLOCK();
508
509 /* An empty string implies AUTH_SYS only. */
510 if (principal[0] != '\0') {
511 ret2 = rpc_gss_set_svc_name_call(principal,
512 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER2);
513 ret3 = rpc_gss_set_svc_name_call(principal,
514 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER3);
515 ret4 = rpc_gss_set_svc_name_call(principal,
516 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER4);
517
518 if (!ret2 || !ret3 || !ret4)
519 printf("nfsd: can't register svc name\n");
520 }
521
522 nfsrvd_pool->sp_minthreads = args->minthreads;
523 nfsrvd_pool->sp_maxthreads = args->maxthreads;
524
525 svc_run(nfsrvd_pool);
526
527 if (principal[0] != '\0') {
528 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2);
529 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3);
530 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4);
531 }
532
533 NFSD_LOCK();
534 newnfs_numnfsd--;
535 nfsrvd_init(1);
536 PROC_LOCK(p);
537 p->p_flag2 &= ~P2_AST_SU;
538 PROC_UNLOCK(p);
539 }
540 NFSD_UNLOCK();
541
542 out:
543 NFSEXITCODE(error);
544 return (error);
545 }
546
547 /*
548 * Initialize the data structures for the server.
549 * Handshake with any new nfsds starting up to avoid any chance of
550 * corruption.
551 */
552 void
nfsrvd_init(int terminating)553 nfsrvd_init(int terminating)
554 {
555
556 NFSD_LOCK_ASSERT();
557
558 if (terminating) {
559 nfsd_master_proc = NULL;
560 NFSD_UNLOCK();
561 nfsrv_freeallbackchannel_xprts();
562 svcpool_destroy(nfsrvd_pool);
563 nfsrvd_pool = NULL;
564 NFSD_LOCK();
565 }
566
567 NFSD_UNLOCK();
568
569 nfsrvd_pool = svcpool_create("nfsd", SYSCTL_STATIC_CHILDREN(_vfs_nfsd));
570 nfsrvd_pool->sp_rcache = NULL;
571 nfsrvd_pool->sp_assign = fhanew_assign;
572 nfsrvd_pool->sp_done = fha_nd_complete;
573
574 NFSD_LOCK();
575 }
576
577