1 /* $NetBSD: nfs_nfsdkrpc.c,v 1.5 2024/07/05 04:31:52 rin 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 1.5 2024/07/05 04:31:52 rin 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 m_freem(nd.nd_mrep);
279
280 if (nd.nd_cred != NULL)
281 crfree(nd.nd_cred);
282
283 if (cacherep == RC_DROPIT) {
284 m_freem(nd.nd_mreq);
285 svc_freereq(rqst);
286 goto out;
287 }
288
289 if (nd.nd_mreq == NULL) {
290 svcerr_decode(rqst);
291 svc_freereq(rqst);
292 goto out;
293 }
294
295 if (nd.nd_repstat & NFSERR_AUTHERR) {
296 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
297 m_freem(nd.nd_mreq);
298 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) {
299 svcerr_systemerr(rqst);
300 }
301 if (rp != NULL) {
302 nfsrvd_sentcache(rp, (rqst->rq_reply_seq != 0 ||
303 SVC_ACK(xprt, NULL)), rqst->rq_reply_seq);
304 }
305 svc_freereq(rqst);
306
307 out:
308 if (softdep_ast_cleanup != NULL)
309 softdep_ast_cleanup();
310 NFSEXITCODE(0);
311 }
312
313 /*
314 * Check the cache and, optionally, do the RPC.
315 * Return the appropriate cache response.
316 */
317 static int
nfs_proc(struct nfsrv_descript * nd,u_int32_t xid,SVCXPRT * xprt,struct nfsrvcache ** rpp)318 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, SVCXPRT *xprt,
319 struct nfsrvcache **rpp)
320 {
321 struct thread *td = curthread;
322 int cacherep = RC_DOIT, isdgram, taglen = -1;
323 struct mbuf *m;
324 u_char tag[NFSV4_SMALLSTR + 1], *tagstr = NULL;
325 u_int32_t minorvers = 0;
326 uint32_t ack;
327
328 *rpp = NULL;
329 if (nd->nd_nam2 == NULL) {
330 nd->nd_flag |= ND_STREAMSOCK;
331 isdgram = 0;
332 } else {
333 isdgram = 1;
334 }
335
336 /*
337 * Two cases:
338 * 1 - For NFSv2 over UDP, if we are near our malloc/mget
339 * limit, just drop the request. There is no
340 * NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the
341 * client will timeout/retry over UDP in a little while.
342 * 2 - nd_repstat == 0 && nd_mreq == NULL, which
343 * means a normal nfs rpc, so check the cache
344 */
345 if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL &&
346 nfsrv_mallocmget_limit()) {
347 cacherep = RC_DROPIT;
348 } else {
349 /*
350 * For NFSv3, play it safe and assume that the client is
351 * doing retries on the same TCP connection.
352 */
353 if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) ==
354 ND_STREAMSOCK)
355 nd->nd_flag |= ND_SAMETCPCONN;
356 nd->nd_retxid = xid;
357 nd->nd_tcpconntime = NFSD_MONOSEC;
358 nd->nd_sockref = xprt->xp_sockref;
359 if ((nd->nd_flag & ND_NFSV4) != 0)
360 nfsd_getminorvers(nd, tag, &tagstr, &taglen,
361 &minorvers);
362 if ((nd->nd_flag & ND_NFSV41) != 0)
363 /* NFSv4.1 caches replies in the session slots. */
364 cacherep = RC_DOIT;
365 else {
366 cacherep = nfsrvd_getcache(nd);
367 ack = 0;
368 SVC_ACK(xprt, &ack);
369 nfsrc_trimcache(xprt->xp_sockref, ack, 0);
370 }
371 }
372
373 /*
374 * Handle the request. There are three cases.
375 * RC_DOIT - do the RPC
376 * RC_REPLY - return the reply already created
377 * RC_DROPIT - just throw the request away
378 */
379 if (cacherep == RC_DOIT) {
380 if ((nd->nd_flag & ND_NFSV41) != 0)
381 nd->nd_xprt = xprt;
382 nfsrvd_dorpc(nd, isdgram, tagstr, taglen, minorvers, td);
383 if ((nd->nd_flag & ND_NFSV41) != 0) {
384 if (nd->nd_repstat != NFSERR_REPLYFROMCACHE &&
385 (nd->nd_flag & ND_SAVEREPLY) != 0) {
386 /* Cache a copy of the reply. */
387 m = m_copym(nd->nd_mreq, 0, M_COPYALL,
388 M_WAITOK);
389 } else
390 m = NULL;
391 if ((nd->nd_flag & ND_HASSEQUENCE) != 0)
392 nfsrv_cache_session(nd->nd_sessionid,
393 nd->nd_slotid, nd->nd_repstat, &m);
394 if (nd->nd_repstat == NFSERR_REPLYFROMCACHE)
395 nd->nd_repstat = 0;
396 cacherep = RC_REPLY;
397 } else {
398 if (nd->nd_repstat == NFSERR_DONTREPLY)
399 cacherep = RC_DROPIT;
400 else
401 cacherep = RC_REPLY;
402 *rpp = nfsrvd_updatecache(nd);
403 }
404 }
405 if (tagstr != NULL && taglen > NFSV4_SMALLSTR)
406 free(tagstr, M_TEMP);
407
408 NFSEXITCODE2(0, nd);
409 return (cacherep);
410 }
411
412 static void
nfssvc_loss(SVCXPRT * xprt)413 nfssvc_loss(SVCXPRT *xprt)
414 {
415 uint32_t ack;
416
417 ack = 0;
418 SVC_ACK(xprt, &ack);
419 nfsrc_trimcache(xprt->xp_sockref, ack, 1);
420 }
421
422 /*
423 * Adds a socket to the list for servicing by nfsds.
424 */
425 int
nfsrvd_addsock(struct file * fp)426 nfsrvd_addsock(struct file *fp)
427 {
428 int siz;
429 struct socket *so;
430 int error = 0;
431 SVCXPRT *xprt;
432 static u_int64_t sockref = 0;
433
434 so = fp->f_data;
435
436 siz = sb_max_adj;
437 error = soreserve(so, siz, siz);
438 if (error)
439 goto out;
440
441 /*
442 * Steal the socket from userland so that it doesn't close
443 * unexpectedly.
444 */
445 if (so->so_type == SOCK_DGRAM)
446 xprt = svc_dg_create(nfsrvd_pool, so, 0, 0);
447 else
448 xprt = svc_vc_create(nfsrvd_pool, so, 0, 0);
449 if (xprt) {
450 fp->f_ops = &badfileops;
451 fp->f_data = NULL;
452 xprt->xp_sockref = ++sockref;
453 if (nfs_minvers == NFS_VER2)
454 svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program,
455 NULL);
456 if (nfs_minvers <= NFS_VER3 && nfs_maxvers >= NFS_VER3)
457 svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program,
458 NULL);
459 if (nfs_maxvers >= NFS_VER4)
460 svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program,
461 NULL);
462 if (so->so_type == SOCK_STREAM)
463 svc_loss_reg(xprt, nfssvc_loss);
464 SVC_RELEASE(xprt);
465 }
466
467 out:
468 NFSEXITCODE(error);
469 return (error);
470 }
471
472 /*
473 * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
474 * until it is killed by a signal.
475 */
476 int
nfsrvd_nfsd(struct thread * td,struct nfsd_nfsd_args * args)477 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args)
478 {
479 char principal[MAXHOSTNAMELEN + 5];
480 struct proc *p;
481 int error = 0;
482 bool_t ret2, ret3, ret4;
483
484 error = copyinstr(args->principal, principal, sizeof (principal),
485 NULL);
486 if (error)
487 goto out;
488
489 /*
490 * Only the first nfsd actually does any work. The RPC code
491 * adds threads to it as needed. Any extra processes offered
492 * by nfsd just exit. If nfsd is new enough, it will call us
493 * once with a structure that specifies how many threads to
494 * use.
495 */
496 NFSD_LOCK();
497 if (newnfs_numnfsd == 0) {
498 p = td->td_proc;
499 PROC_LOCK(p);
500 p->p_flag2 |= P2_AST_SU;
501 PROC_UNLOCK(p);
502 newnfs_numnfsd++;
503
504 NFSD_UNLOCK();
505
506 /* An empty string implies AUTH_SYS only. */
507 if (principal[0] != '\0') {
508 ret2 = rpc_gss_set_svc_name_call(principal,
509 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER2);
510 ret3 = rpc_gss_set_svc_name_call(principal,
511 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER3);
512 ret4 = rpc_gss_set_svc_name_call(principal,
513 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER4);
514
515 if (!ret2 || !ret3 || !ret4)
516 printf("nfsd: can't register svc name\n");
517 }
518
519 nfsrvd_pool->sp_minthreads = args->minthreads;
520 nfsrvd_pool->sp_maxthreads = args->maxthreads;
521
522 svc_run(nfsrvd_pool);
523
524 if (principal[0] != '\0') {
525 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2);
526 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3);
527 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4);
528 }
529
530 NFSD_LOCK();
531 newnfs_numnfsd--;
532 nfsrvd_init(1);
533 PROC_LOCK(p);
534 p->p_flag2 &= ~P2_AST_SU;
535 PROC_UNLOCK(p);
536 }
537 NFSD_UNLOCK();
538
539 out:
540 NFSEXITCODE(error);
541 return (error);
542 }
543
544 /*
545 * Initialize the data structures for the server.
546 * Handshake with any new nfsds starting up to avoid any chance of
547 * corruption.
548 */
549 void
nfsrvd_init(int terminating)550 nfsrvd_init(int terminating)
551 {
552
553 NFSD_LOCK_ASSERT();
554
555 if (terminating) {
556 nfsd_master_proc = NULL;
557 NFSD_UNLOCK();
558 nfsrv_freeallbackchannel_xprts();
559 svcpool_destroy(nfsrvd_pool);
560 nfsrvd_pool = NULL;
561 NFSD_LOCK();
562 }
563
564 NFSD_UNLOCK();
565
566 nfsrvd_pool = svcpool_create("nfsd", SYSCTL_STATIC_CHILDREN(_vfs_nfsd));
567 nfsrvd_pool->sp_rcache = NULL;
568 nfsrvd_pool->sp_assign = fhanew_assign;
569 nfsrvd_pool->sp_done = fha_nd_complete;
570
571 NFSD_LOCK();
572 }
573
574