1 /* $NetBSD: nfs_clkrpc.c,v 1.2 2016/12/13 22:17:33 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/nfsclient/nfs_clkrpc.c 255216 2013-09-04 22:47:56Z rmacklem "); */
37 __RCSID("$NetBSD: nfs_clkrpc.c,v 1.2 2016/12/13 22:17:33 pgoyette Exp $");
38
39 #ifdef NOTYET /* _KERNEL_OPT */
40 #include "opt_kgssapi.h"
41 #endif
42
43 #include <fs/nfs/common/nfsport.h>
44
45 #include <rpc/rpc.h>
46 #include <rpc/rpcsec_gss.h>
47 #include <rpc/replay.h>
48
49
50 NFSDLOCKMUTEX;
51
52 extern SVCPOOL *nfscbd_pool;
53
54 static int nfs_cbproc(struct nfsrv_descript *, u_int32_t);
55
56 extern u_long sb_max_adj;
57 extern int nfs_numnfscbd;
58 extern int nfscl_debuglevel;
59
60 /*
61 * NFS client system calls for handling callbacks.
62 */
63
64 /*
65 * Handles server to client callbacks.
66 */
67 static void
nfscb_program(struct svc_req * rqst,SVCXPRT * xprt)68 nfscb_program(struct svc_req *rqst, SVCXPRT *xprt)
69 {
70 struct nfsrv_descript nd;
71 int cacherep, credflavor;
72
73 memset(&nd, 0, sizeof(nd));
74 if (rqst->rq_proc != NFSPROC_NULL &&
75 rqst->rq_proc != NFSV4PROC_CBCOMPOUND) {
76 svcerr_noproc(rqst);
77 svc_freereq(rqst);
78 return;
79 }
80 nd.nd_procnum = rqst->rq_proc;
81 nd.nd_flag = (ND_NFSCB | ND_NFSV4);
82
83 /*
84 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 -
85 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP
86 * mounts.
87 */
88 nd.nd_mrep = rqst->rq_args;
89 rqst->rq_args = NULL;
90 newnfs_realign(&nd.nd_mrep, M_WAITOK);
91 nd.nd_md = nd.nd_mrep;
92 nd.nd_dpos = mtod(nd.nd_md, caddr_t);
93 nd.nd_nam = svc_getrpccaller(rqst);
94 nd.nd_nam2 = rqst->rq_addr;
95 nd.nd_mreq = NULL;
96 nd.nd_cred = NULL;
97
98 NFSCL_DEBUG(1, "cbproc=%d\n",nd.nd_procnum);
99 if (nd.nd_procnum != NFSPROC_NULL) {
100 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) {
101 svcerr_weakauth(rqst);
102 svc_freereq(rqst);
103 m_freem(nd.nd_mrep);
104 return;
105 }
106
107 /* For now, I don't care what credential flavor was used. */
108 #ifdef notyet
109 #ifdef MAC
110 mac_cred_associate_nfsd(nd.nd_cred);
111 #endif
112 #endif
113 cacherep = nfs_cbproc(&nd, rqst->rq_xid);
114 } else {
115 NFSMGET(nd.nd_mreq);
116 nd.nd_mreq->m_len = 0;
117 cacherep = RC_REPLY;
118 }
119 if (nd.nd_mrep != NULL)
120 m_freem(nd.nd_mrep);
121
122 if (nd.nd_cred != NULL)
123 crfree(nd.nd_cred);
124
125 if (cacherep == RC_DROPIT) {
126 if (nd.nd_mreq != NULL)
127 m_freem(nd.nd_mreq);
128 svc_freereq(rqst);
129 return;
130 }
131
132 if (nd.nd_mreq == NULL) {
133 svcerr_decode(rqst);
134 svc_freereq(rqst);
135 return;
136 }
137
138 if (nd.nd_repstat & NFSERR_AUTHERR) {
139 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR);
140 if (nd.nd_mreq != NULL)
141 m_freem(nd.nd_mreq);
142 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq))
143 svcerr_systemerr(rqst);
144 else
145 NFSCL_DEBUG(1, "cbrep sent\n");
146 svc_freereq(rqst);
147 }
148
149 /*
150 * Check the cache and, optionally, do the RPC.
151 * Return the appropriate cache response.
152 */
153 static int
nfs_cbproc(struct nfsrv_descript * nd,u_int32_t xid)154 nfs_cbproc(struct nfsrv_descript *nd, u_int32_t xid)
155 {
156 struct thread *td = curthread;
157 int cacherep;
158
159 if (nd->nd_nam2 == NULL)
160 nd->nd_flag |= ND_STREAMSOCK;
161
162 nfscl_docb(nd, td);
163 if (nd->nd_repstat == NFSERR_DONTREPLY)
164 cacherep = RC_DROPIT;
165 else
166 cacherep = RC_REPLY;
167 return (cacherep);
168 }
169
170 /*
171 * Adds a socket to the list for servicing by nfscbds.
172 */
173 int
nfscbd_addsock(struct file * fp)174 nfscbd_addsock(struct file *fp)
175 {
176 int siz;
177 struct socket *so;
178 int error;
179 SVCXPRT *xprt;
180
181 so = fp->f_data;
182
183 siz = sb_max_adj;
184 error = soreserve(so, siz, siz);
185 if (error)
186 return (error);
187
188 /*
189 * Steal the socket from userland so that it doesn't close
190 * unexpectedly.
191 */
192 if (so->so_type == SOCK_DGRAM)
193 xprt = svc_dg_create(nfscbd_pool, so, 0, 0);
194 else
195 xprt = svc_vc_create(nfscbd_pool, so, 0, 0);
196 if (xprt) {
197 fp->f_ops = &badfileops;
198 fp->f_data = NULL;
199 svc_reg(xprt, NFS_CALLBCKPROG, NFSV4_CBVERS, nfscb_program,
200 NULL);
201 SVC_RELEASE(xprt);
202 }
203
204 return (0);
205 }
206
207 /*
208 * Called by nfssvc() for nfscbds. Just loops around servicing rpc requests
209 * until it is killed by a signal.
210 *
211 * For now, only support callbacks via RPCSEC_GSS if there is a KerberosV
212 * keytab entry with a host based entry in it on the client. (I'm not even
213 * sure that getting Acceptor credentials for a user principal with a
214 * credentials cache is possible, but even if it is, major changes to the
215 * kgssapi would be required.)
216 * I don't believe that this is a serious limitation since, as of 2009, most
217 * NFSv4 servers supporting callbacks are using AUTH_SYS for callbacks even
218 * when the client is using RPCSEC_GSS. (This BSD server uses AUTH_SYS
219 * for callbacks unless nfsrv_gsscallbackson is set non-zero.)
220 */
221 int
nfscbd_nfsd(struct thread * td,struct nfsd_nfscbd_args * args)222 nfscbd_nfsd(struct thread *td, struct nfsd_nfscbd_args *args)
223 {
224 char principal[128];
225 int error;
226
227 if (args != NULL) {
228 error = copyinstr(args->principal, principal,
229 sizeof(principal), NULL);
230 if (error)
231 return (error);
232 } else {
233 principal[0] = '\0';
234 }
235
236 /*
237 * Only the first nfsd actually does any work. The RPC code
238 * adds threads to it as needed. Any extra processes offered
239 * by nfsd just exit. If nfsd is new enough, it will call us
240 * once with a structure that specifies how many threads to
241 * use.
242 */
243 NFSD_LOCK();
244 if (nfs_numnfscbd == 0) {
245 nfs_numnfscbd++;
246
247 NFSD_UNLOCK();
248
249 if (principal[0] != '\0')
250 rpc_gss_set_svc_name_call(principal, "kerberosv5",
251 GSS_C_INDEFINITE, NFS_CALLBCKPROG, NFSV4_CBVERS);
252
253 nfscbd_pool->sp_minthreads = 4;
254 nfscbd_pool->sp_maxthreads = 4;
255
256 svc_run(nfscbd_pool);
257
258 rpc_gss_clear_svc_name_call(NFS_CALLBCKPROG, NFSV4_CBVERS);
259
260 NFSD_LOCK();
261 nfs_numnfscbd--;
262 nfsrvd_cbinit(1);
263 }
264 NFSD_UNLOCK();
265
266 return (0);
267 }
268
269 /*
270 * Initialize the data structures for the server.
271 * Handshake with any new nfsds starting up to avoid any chance of
272 * corruption.
273 */
274 void
nfsrvd_cbinit(int terminating)275 nfsrvd_cbinit(int terminating)
276 {
277
278 NFSD_LOCK_ASSERT();
279
280 if (terminating) {
281 /* Wait for any xprt registrations to complete. */
282 while (nfs_numnfscbd > 0)
283 msleep(&nfs_numnfscbd, NFSDLOCKMUTEXPTR, PZERO,
284 "nfscbdt", 0);
285 }
286
287 if (nfscbd_pool == NULL) {
288 NFSD_UNLOCK();
289 nfscbd_pool = svcpool_create("nfscbd", NULL);
290 nfscbd_pool->sp_rcache = NULL;
291 nfscbd_pool->sp_assign = NULL;
292 nfscbd_pool->sp_done = NULL;
293 NFSD_LOCK();
294 }
295 }
296
297