1 /* $NetBSD: nfs_clkrpc.c,v 1.1.1.1 2013/09/30 07:19:04 dholland 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/nfsclient/nfs_clkrpc.c 255216 2013-09-04 22:47:56Z rmacklem "); */
37 __RCSID("$NetBSD: nfs_clkrpc.c,v 1.1.1.1 2013/09/30 07:19:04 dholland Exp $");
38
39 #include "opt_kgssapi.h"
40
41 #include <fs/nfs/nfsport.h>
42
43 #include <rpc/rpc.h>
44 #include <rpc/rpcsec_gss.h>
45 #include <rpc/replay.h>
46
47
48 NFSDLOCKMUTEX;
49
50 extern SVCPOOL *nfscbd_pool;
51
52 static int nfs_cbproc(struct nfsrv_descript *, u_int32_t);
53
54 extern u_long sb_max_adj;
55 extern int nfs_numnfscbd;
56 extern int nfscl_debuglevel;
57
58 /*
59 * NFS client system calls for handling callbacks.
60 */
61
62 /*
63 * Handles server to client callbacks.
64 */
65 static void
nfscb_program(struct svc_req * rqst,SVCXPRT * xprt)66 nfscb_program(struct svc_req *rqst, SVCXPRT *xprt)
67 {
68 struct nfsrv_descript nd;
69 int cacherep, credflavor;
70
71 memset(&nd, 0, sizeof(nd));
72 if (rqst->rq_proc != NFSPROC_NULL &&
73 rqst->rq_proc != NFSV4PROC_CBCOMPOUND) {
74 svcerr_noproc(rqst);
75 svc_freereq(rqst);
76 return;
77 }
78 nd.nd_procnum = rqst->rq_proc;
79 nd.nd_flag = (ND_NFSCB | ND_NFSV4);
80
81 /*
82 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 -
83 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP
84 * mounts.
85 */
86 nd.nd_mrep = rqst->rq_args;
87 rqst->rq_args = NULL;
88 newnfs_realign(&nd.nd_mrep, M_WAITOK);
89 nd.nd_md = nd.nd_mrep;
90 nd.nd_dpos = mtod(nd.nd_md, caddr_t);
91 nd.nd_nam = svc_getrpccaller(rqst);
92 nd.nd_nam2 = rqst->rq_addr;
93 nd.nd_mreq = NULL;
94 nd.nd_cred = NULL;
95
96 NFSCL_DEBUG(1, "cbproc=%d\n",nd.nd_procnum);
97 if (nd.nd_procnum != NFSPROC_NULL) {
98 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) {
99 svcerr_weakauth(rqst);
100 svc_freereq(rqst);
101 m_freem(nd.nd_mrep);
102 return;
103 }
104
105 /* For now, I don't care what credential flavor was used. */
106 #ifdef notyet
107 #ifdef MAC
108 mac_cred_associate_nfsd(nd.nd_cred);
109 #endif
110 #endif
111 cacherep = nfs_cbproc(&nd, rqst->rq_xid);
112 } else {
113 NFSMGET(nd.nd_mreq);
114 nd.nd_mreq->m_len = 0;
115 cacherep = RC_REPLY;
116 }
117 if (nd.nd_mrep != NULL)
118 m_freem(nd.nd_mrep);
119
120 if (nd.nd_cred != NULL)
121 crfree(nd.nd_cred);
122
123 if (cacherep == RC_DROPIT) {
124 if (nd.nd_mreq != NULL)
125 m_freem(nd.nd_mreq);
126 svc_freereq(rqst);
127 return;
128 }
129
130 if (nd.nd_mreq == NULL) {
131 svcerr_decode(rqst);
132 svc_freereq(rqst);
133 return;
134 }
135
136 if (nd.nd_repstat & NFSERR_AUTHERR) {
137 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
138 if (nd.nd_mreq != NULL)
139 m_freem(nd.nd_mreq);
140 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq))
141 svcerr_systemerr(rqst);
142 else
143 NFSCL_DEBUG(1, "cbrep sent\n");
144 svc_freereq(rqst);
145 }
146
147 /*
148 * Check the cache and, optionally, do the RPC.
149 * Return the appropriate cache response.
150 */
151 static int
nfs_cbproc(struct nfsrv_descript * nd,u_int32_t xid)152 nfs_cbproc(struct nfsrv_descript *nd, u_int32_t xid)
153 {
154 struct thread *td = curthread;
155 int cacherep;
156
157 if (nd->nd_nam2 == NULL)
158 nd->nd_flag |= ND_STREAMSOCK;
159
160 nfscl_docb(nd, td);
161 if (nd->nd_repstat == NFSERR_DONTREPLY)
162 cacherep = RC_DROPIT;
163 else
164 cacherep = RC_REPLY;
165 return (cacherep);
166 }
167
168 /*
169 * Adds a socket to the list for servicing by nfscbds.
170 */
171 int
nfscbd_addsock(struct file * fp)172 nfscbd_addsock(struct file *fp)
173 {
174 int siz;
175 struct socket *so;
176 int error;
177 SVCXPRT *xprt;
178
179 so = fp->f_data;
180
181 siz = sb_max_adj;
182 error = soreserve(so, siz, siz);
183 if (error)
184 return (error);
185
186 /*
187 * Steal the socket from userland so that it doesn't close
188 * unexpectedly.
189 */
190 if (so->so_type == SOCK_DGRAM)
191 xprt = svc_dg_create(nfscbd_pool, so, 0, 0);
192 else
193 xprt = svc_vc_create(nfscbd_pool, so, 0, 0);
194 if (xprt) {
195 fp->f_ops = &badfileops;
196 fp->f_data = NULL;
197 svc_reg(xprt, NFS_CALLBCKPROG, NFSV4_CBVERS, nfscb_program,
198 NULL);
199 SVC_RELEASE(xprt);
200 }
201
202 return (0);
203 }
204
205 /*
206 * Called by nfssvc() for nfscbds. Just loops around servicing rpc requests
207 * until it is killed by a signal.
208 *
209 * For now, only support callbacks via RPCSEC_GSS if there is a KerberosV
210 * keytab entry with a host based entry in it on the client. (I'm not even
211 * sure that getting Acceptor credentials for a user principal with a
212 * credentials cache is possible, but even if it is, major changes to the
213 * kgssapi would be required.)
214 * I don't believe that this is a serious limitation since, as of 2009, most
215 * NFSv4 servers supporting callbacks are using AUTH_SYS for callbacks even
216 * when the client is using RPCSEC_GSS. (This BSD server uses AUTH_SYS
217 * for callbacks unless nfsrv_gsscallbackson is set non-zero.)
218 */
219 int
nfscbd_nfsd(struct thread * td,struct nfsd_nfscbd_args * args)220 nfscbd_nfsd(struct thread *td, struct nfsd_nfscbd_args *args)
221 {
222 char principal[128];
223 int error;
224
225 if (args != NULL) {
226 error = copyinstr(args->principal, principal,
227 sizeof(principal), NULL);
228 if (error)
229 return (error);
230 } else {
231 principal[0] = '\0';
232 }
233
234 /*
235 * Only the first nfsd actually does any work. The RPC code
236 * adds threads to it as needed. Any extra processes offered
237 * by nfsd just exit. If nfsd is new enough, it will call us
238 * once with a structure that specifies how many threads to
239 * use.
240 */
241 NFSD_LOCK();
242 if (nfs_numnfscbd == 0) {
243 nfs_numnfscbd++;
244
245 NFSD_UNLOCK();
246
247 if (principal[0] != '\0')
248 rpc_gss_set_svc_name_call(principal, "kerberosv5",
249 GSS_C_INDEFINITE, NFS_CALLBCKPROG, NFSV4_CBVERS);
250
251 nfscbd_pool->sp_minthreads = 4;
252 nfscbd_pool->sp_maxthreads = 4;
253
254 svc_run(nfscbd_pool);
255
256 rpc_gss_clear_svc_name_call(NFS_CALLBCKPROG, NFSV4_CBVERS);
257
258 NFSD_LOCK();
259 nfs_numnfscbd--;
260 nfsrvd_cbinit(1);
261 }
262 NFSD_UNLOCK();
263
264 return (0);
265 }
266
267 /*
268 * Initialize the data structures for the server.
269 * Handshake with any new nfsds starting up to avoid any chance of
270 * corruption.
271 */
272 void
nfsrvd_cbinit(int terminating)273 nfsrvd_cbinit(int terminating)
274 {
275
276 NFSD_LOCK_ASSERT();
277
278 if (terminating) {
279 /* Wait for any xprt registrations to complete. */
280 while (nfs_numnfscbd > 0)
281 msleep(&nfs_numnfscbd, NFSDLOCKMUTEXPTR, PZERO,
282 "nfscbdt", 0);
283 }
284
285 if (nfscbd_pool == NULL) {
286 NFSD_UNLOCK();
287 nfscbd_pool = svcpool_create("nfscbd", NULL);
288 nfscbd_pool->sp_rcache = NULL;
289 nfscbd_pool->sp_assign = NULL;
290 nfscbd_pool->sp_done = NULL;
291 NFSD_LOCK();
292 }
293 }
294
295