1 /* $NetBSD: nfs_nfsdkrpc.c,v 1.2 2014/03/25 16:30:28 christos 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 249596 2013-04-17 22:42:43Z ken "); */
37 __RCSID("$NetBSD: nfs_nfsdkrpc.c,v 1.2 2014/03/25 16:30:28 christos Exp $");
38
39 #include "opt_inet6.h"
40 #include "opt_kgssapi.h"
41
42 #include <fs/nfs/nfsport.h>
43
44 #include <rpc/rpc.h>
45 #include <rpc/rpcsec_gss.h>
46
47 #include <nfs/nfs_fha.h>
48 #include <fs/nfsserver/nfs_fha_new.h>
49
50 #include <security/mac/mac_framework.h>
51
52 NFSDLOCKMUTEX;
53 NFSV4ROOTLOCKMUTEX;
54 struct nfsv4lock nfsd_suspend_lock;
55
56 /*
57 * Mapping of old NFS Version 2 RPC numbers to generic numbers.
58 */
59 int newnfs_nfsv3_procid[NFS_V3NPROCS] = {
60 NFSPROC_NULL,
61 NFSPROC_GETATTR,
62 NFSPROC_SETATTR,
63 NFSPROC_NOOP,
64 NFSPROC_LOOKUP,
65 NFSPROC_READLINK,
66 NFSPROC_READ,
67 NFSPROC_NOOP,
68 NFSPROC_WRITE,
69 NFSPROC_CREATE,
70 NFSPROC_REMOVE,
71 NFSPROC_RENAME,
72 NFSPROC_LINK,
73 NFSPROC_SYMLINK,
74 NFSPROC_MKDIR,
75 NFSPROC_RMDIR,
76 NFSPROC_READDIR,
77 NFSPROC_FSSTAT,
78 NFSPROC_NOOP,
79 NFSPROC_NOOP,
80 NFSPROC_NOOP,
81 NFSPROC_NOOP,
82 };
83
84
85 SYSCTL_DECL(_vfs_nfsd);
86
87 SVCPOOL *nfsrvd_pool;
88
89 static int nfs_privport = 0;
90 SYSCTL_INT(_vfs_nfsd, OID_AUTO, nfs_privport, CTLFLAG_RW,
91 &nfs_privport, 0,
92 "Only allow clients using a privileged port for NFSv2 and 3");
93
94 static int nfs_minvers = NFS_VER2;
95 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_min_nfsvers, CTLFLAG_RW,
96 &nfs_minvers, 0, "The lowest version of NFS handled by the server");
97
98 static int nfs_maxvers = NFS_VER4;
99 SYSCTL_INT(_vfs_nfsd, OID_AUTO, server_max_nfsvers, CTLFLAG_RW,
100 &nfs_maxvers, 0, "The highest version of NFS handled by the server");
101
102 static int nfs_proc(struct nfsrv_descript *, u_int32_t, struct socket *,
103 u_int64_t, struct nfsrvcache **);
104
105 extern u_long sb_max_adj;
106 extern int newnfs_numnfsd;
107 extern struct proc *nfsd_master_proc;
108
109 /*
110 * NFS server system calls
111 */
112
113 static void
nfssvc_program(struct svc_req * rqst,SVCXPRT * xprt)114 nfssvc_program(struct svc_req *rqst, SVCXPRT *xprt)
115 {
116 struct nfsrv_descript nd;
117 struct nfsrvcache *rp = NULL;
118 int cacherep, credflavor;
119
120 memset(&nd, 0, sizeof(nd));
121 if (rqst->rq_vers == NFS_VER2) {
122 if (rqst->rq_proc > NFSV2PROC_STATFS) {
123 svcerr_noproc(rqst);
124 svc_freereq(rqst);
125 goto out;
126 }
127 nd.nd_procnum = newnfs_nfsv3_procid[rqst->rq_proc];
128 nd.nd_flag = ND_NFSV2;
129 } else if (rqst->rq_vers == NFS_VER3) {
130 if (rqst->rq_proc >= NFS_V3NPROCS) {
131 svcerr_noproc(rqst);
132 svc_freereq(rqst);
133 goto out;
134 }
135 nd.nd_procnum = rqst->rq_proc;
136 nd.nd_flag = ND_NFSV3;
137 } else {
138 if (rqst->rq_proc != NFSPROC_NULL &&
139 rqst->rq_proc != NFSV4PROC_COMPOUND) {
140 svcerr_noproc(rqst);
141 svc_freereq(rqst);
142 goto out;
143 }
144 nd.nd_procnum = rqst->rq_proc;
145 nd.nd_flag = ND_NFSV4;
146 }
147
148 /*
149 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 -
150 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP
151 * mounts.
152 */
153 nd.nd_mrep = rqst->rq_args;
154 rqst->rq_args = NULL;
155 newnfs_realign(&nd.nd_mrep, M_WAITOK);
156 nd.nd_md = nd.nd_mrep;
157 nd.nd_dpos = mtod(nd.nd_md, caddr_t);
158 nd.nd_nam = svc_getrpccaller(rqst);
159 nd.nd_nam2 = rqst->rq_addr;
160 nd.nd_mreq = NULL;
161 nd.nd_cred = NULL;
162
163 if (nfs_privport && (nd.nd_flag & ND_NFSV4) == 0) {
164 /* Check if source port is privileged */
165 u_short port;
166 struct sockaddr *nam = nd.nd_nam;
167 struct sockaddr_in *sin;
168
169 sin = (struct sockaddr_in *)nam;
170 /*
171 * INET/INET6 - same code:
172 * sin_port and sin6_port are at same offset
173 */
174 port = ntohs(sin->sin_port);
175 if (port >= IPPORT_RESERVED &&
176 nd.nd_procnum != NFSPROC_NULL) {
177 #ifdef INET6
178 char b6[INET6_ADDRSTRLEN];
179 #if defined(KLD_MODULE)
180 /* Do not use ip6_sprintf: the nfs module should work without INET6. */
181 #define ip6_sprintf(buf, a) \
182 (snprintf((buf), sizeof(buf), "%x:%x:%x:%x:%x:%x:%x:%x", \
183 (a)->s6_addr16[0], (a)->s6_addr16[1], \
184 (a)->s6_addr16[2], (a)->s6_addr16[3], \
185 (a)->s6_addr16[4], (a)->s6_addr16[5], \
186 (a)->s6_addr16[6], (a)->s6_addr16[7]), \
187 (buf))
188 #endif
189 #endif
190 printf("NFS request from unprivileged port (%s:%d)\n",
191 #ifdef INET6
192 sin->sin_family == AF_INET6 ?
193 ip6_sprintf(b6, &satosin6(sin)->sin6_addr) :
194 #if defined(KLD_MODULE)
195 #undef ip6_sprintf
196 #endif
197 #endif
198 inet_ntoa(sin->sin_addr), port);
199 svcerr_weakauth(rqst);
200 svc_freereq(rqst);
201 m_freem(nd.nd_mrep);
202 goto out;
203 }
204 }
205
206 if (nd.nd_procnum != NFSPROC_NULL) {
207 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) {
208 svcerr_weakauth(rqst);
209 svc_freereq(rqst);
210 m_freem(nd.nd_mrep);
211 goto out;
212 }
213
214 /* Set the flag based on credflavor */
215 if (credflavor == RPCSEC_GSS_KRB5) {
216 nd.nd_flag |= ND_GSS;
217 } else if (credflavor == RPCSEC_GSS_KRB5I) {
218 nd.nd_flag |= (ND_GSS | ND_GSSINTEGRITY);
219 } else if (credflavor == RPCSEC_GSS_KRB5P) {
220 nd.nd_flag |= (ND_GSS | ND_GSSPRIVACY);
221 } else if (credflavor != AUTH_SYS) {
222 svcerr_weakauth(rqst);
223 svc_freereq(rqst);
224 m_freem(nd.nd_mrep);
225 goto out;
226 }
227
228 #ifdef MAC
229 mac_cred_associate_nfsd(nd.nd_cred);
230 #endif
231 /*
232 * Get a refcnt (shared lock) on nfsd_suspend_lock.
233 * NFSSVC_SUSPENDNFSD will take an exclusive lock on
234 * nfsd_suspend_lock to suspend these threads.
235 * This must be done here, before the check of
236 * nfsv4root exports by nfsvno_v4rootexport().
237 */
238 NFSLOCKV4ROOTMUTEX();
239 nfsv4_getref(&nfsd_suspend_lock, NULL, NFSV4ROOTLOCKMUTEXPTR,
240 NULL);
241 NFSUNLOCKV4ROOTMUTEX();
242
243 if ((nd.nd_flag & ND_NFSV4) != 0) {
244 nd.nd_repstat = nfsvno_v4rootexport(&nd);
245 if (nd.nd_repstat != 0) {
246 NFSLOCKV4ROOTMUTEX();
247 nfsv4_relref(&nfsd_suspend_lock);
248 NFSUNLOCKV4ROOTMUTEX();
249 svcerr_weakauth(rqst);
250 svc_freereq(rqst);
251 m_freem(nd.nd_mrep);
252 goto out;
253 }
254 }
255
256 cacherep = nfs_proc(&nd, rqst->rq_xid, xprt->xp_socket,
257 xprt->xp_sockref, &rp);
258 NFSLOCKV4ROOTMUTEX();
259 nfsv4_relref(&nfsd_suspend_lock);
260 NFSUNLOCKV4ROOTMUTEX();
261 } else {
262 NFSMGET(nd.nd_mreq);
263 nd.nd_mreq->m_len = 0;
264 cacherep = RC_REPLY;
265 }
266 if (nd.nd_mrep != NULL)
267 m_freem(nd.nd_mrep);
268
269 if (nd.nd_cred != NULL)
270 crfree(nd.nd_cred);
271
272 if (cacherep == RC_DROPIT) {
273 if (nd.nd_mreq != NULL)
274 m_freem(nd.nd_mreq);
275 svc_freereq(rqst);
276 goto out;
277 }
278
279 if (nd.nd_mreq == NULL) {
280 svcerr_decode(rqst);
281 svc_freereq(rqst);
282 goto out;
283 }
284
285 if (nd.nd_repstat & NFSERR_AUTHERR) {
286 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
287 if (nd.nd_mreq != NULL)
288 m_freem(nd.nd_mreq);
289 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) {
290 svcerr_systemerr(rqst);
291 }
292 if (rp != NULL)
293 nfsrvd_sentcache(rp, xprt->xp_socket, 0);
294 svc_freereq(rqst);
295
296 out:
297 NFSEXITCODE(0);
298 }
299
300 /*
301 * Check the cache and, optionally, do the RPC.
302 * Return the appropriate cache response.
303 */
304 static int
nfs_proc(struct nfsrv_descript * nd,u_int32_t xid,struct socket * so,u_int64_t sockref,struct nfsrvcache ** rpp)305 nfs_proc(struct nfsrv_descript *nd, u_int32_t xid, struct socket *so,
306 u_int64_t sockref, struct nfsrvcache **rpp)
307 {
308 struct thread *td = curthread;
309 int cacherep = RC_DOIT, isdgram;
310
311 *rpp = NULL;
312 if (nd->nd_nam2 == NULL) {
313 nd->nd_flag |= ND_STREAMSOCK;
314 isdgram = 0;
315 } else {
316 isdgram = 1;
317 }
318
319 /*
320 * Two cases:
321 * 1 - For NFSv2 over UDP, if we are near our malloc/mget
322 * limit, just drop the request. There is no
323 * NFSERR_RESOURCE or NFSERR_DELAY for NFSv2 and the
324 * client will timeout/retry over UDP in a little while.
325 * 2 - nd_repstat == 0 && nd_mreq == NULL, which
326 * means a normal nfs rpc, so check the cache
327 */
328 if ((nd->nd_flag & ND_NFSV2) && nd->nd_nam2 != NULL &&
329 nfsrv_mallocmget_limit()) {
330 cacherep = RC_DROPIT;
331 } else {
332 /*
333 * For NFSv3, play it safe and assume that the client is
334 * doing retries on the same TCP connection.
335 */
336 if ((nd->nd_flag & (ND_NFSV4 | ND_STREAMSOCK)) ==
337 ND_STREAMSOCK)
338 nd->nd_flag |= ND_SAMETCPCONN;
339 nd->nd_retxid = xid;
340 nd->nd_tcpconntime = NFSD_MONOSEC;
341 nd->nd_sockref = sockref;
342 cacherep = nfsrvd_getcache(nd, so);
343 }
344
345 /*
346 * Handle the request. There are three cases.
347 * RC_DOIT - do the RPC
348 * RC_REPLY - return the reply already created
349 * RC_DROPIT - just throw the request away
350 */
351 if (cacherep == RC_DOIT) {
352 nfsrvd_dorpc(nd, isdgram, td);
353 if (nd->nd_repstat == NFSERR_DONTREPLY)
354 cacherep = RC_DROPIT;
355 else
356 cacherep = RC_REPLY;
357 *rpp = nfsrvd_updatecache(nd, so);
358 }
359
360 NFSEXITCODE2(0, nd);
361 return (cacherep);
362 }
363
364 /*
365 * Adds a socket to the list for servicing by nfsds.
366 */
367 int
nfsrvd_addsock(struct file * fp)368 nfsrvd_addsock(struct file *fp)
369 {
370 int siz;
371 struct socket *so;
372 int error = 0;
373 SVCXPRT *xprt;
374 static u_int64_t sockref = 0;
375
376 so = fp->f_data;
377
378 siz = sb_max_adj;
379 error = soreserve(so, siz, siz);
380 if (error)
381 goto out;
382
383 /*
384 * Steal the socket from userland so that it doesn't close
385 * unexpectedly.
386 */
387 if (so->so_type == SOCK_DGRAM)
388 xprt = svc_dg_create(nfsrvd_pool, so, 0, 0);
389 else
390 xprt = svc_vc_create(nfsrvd_pool, so, 0, 0);
391 if (xprt) {
392 fp->f_ops = &badfileops;
393 fp->f_data = NULL;
394 xprt->xp_sockref = ++sockref;
395 if (nfs_minvers == NFS_VER2)
396 svc_reg(xprt, NFS_PROG, NFS_VER2, nfssvc_program,
397 NULL);
398 if (nfs_minvers <= NFS_VER3 && nfs_maxvers >= NFS_VER3)
399 svc_reg(xprt, NFS_PROG, NFS_VER3, nfssvc_program,
400 NULL);
401 if (nfs_maxvers >= NFS_VER4)
402 svc_reg(xprt, NFS_PROG, NFS_VER4, nfssvc_program,
403 NULL);
404 SVC_RELEASE(xprt);
405 }
406
407 out:
408 NFSEXITCODE(error);
409 return (error);
410 }
411
412 /*
413 * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
414 * until it is killed by a signal.
415 */
416 int
nfsrvd_nfsd(struct thread * td,struct nfsd_nfsd_args * args)417 nfsrvd_nfsd(struct thread *td, struct nfsd_nfsd_args *args)
418 {
419 char principal[MAXHOSTNAMELEN + 5];
420 int error = 0;
421 bool_t ret2, ret3, ret4;
422
423 error = copyinstr(args->principal, principal, sizeof (principal),
424 NULL);
425 if (error)
426 goto out;
427
428 /*
429 * Only the first nfsd actually does any work. The RPC code
430 * adds threads to it as needed. Any extra processes offered
431 * by nfsd just exit. If nfsd is new enough, it will call us
432 * once with a structure that specifies how many threads to
433 * use.
434 */
435 NFSD_LOCK();
436 if (newnfs_numnfsd == 0) {
437 newnfs_numnfsd++;
438
439 NFSD_UNLOCK();
440
441 /* An empty string implies AUTH_SYS only. */
442 if (principal[0] != '\0') {
443 ret2 = rpc_gss_set_svc_name_call(principal,
444 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER2);
445 ret3 = rpc_gss_set_svc_name_call(principal,
446 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER3);
447 ret4 = rpc_gss_set_svc_name_call(principal,
448 "kerberosv5", GSS_C_INDEFINITE, NFS_PROG, NFS_VER4);
449
450 if (!ret2 || !ret3 || !ret4)
451 printf("nfsd: can't register svc name\n");
452 }
453
454 nfsrvd_pool->sp_minthreads = args->minthreads;
455 nfsrvd_pool->sp_maxthreads = args->maxthreads;
456
457 svc_run(nfsrvd_pool);
458
459 if (principal[0] != '\0') {
460 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER2);
461 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER3);
462 rpc_gss_clear_svc_name_call(NFS_PROG, NFS_VER4);
463 }
464
465 NFSD_LOCK();
466 newnfs_numnfsd--;
467 nfsrvd_init(1);
468 }
469 NFSD_UNLOCK();
470
471 out:
472 NFSEXITCODE(error);
473 return (error);
474 }
475
476 /*
477 * Initialize the data structures for the server.
478 * Handshake with any new nfsds starting up to avoid any chance of
479 * corruption.
480 */
481 void
nfsrvd_init(int terminating)482 nfsrvd_init(int terminating)
483 {
484
485 NFSD_LOCK_ASSERT();
486
487 if (terminating) {
488 nfsd_master_proc = NULL;
489 NFSD_UNLOCK();
490 svcpool_destroy(nfsrvd_pool);
491 nfsrvd_pool = NULL;
492 NFSD_LOCK();
493 }
494
495 NFSD_UNLOCK();
496
497 nfsrvd_pool = svcpool_create("nfsd", SYSCTL_STATIC_CHILDREN(_vfs_nfsd));
498 nfsrvd_pool->sp_rcache = NULL;
499 nfsrvd_pool->sp_assign = fhanew_assign;
500 nfsrvd_pool->sp_done = fha_nd_complete;
501
502 NFSD_LOCK();
503 }
504
505