1 /* $NetBSD: nfs_clkrpc.c,v 1.3 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/nfsclient/nfs_clkrpc.c 255216 2013-09-04 22:47:56Z rmacklem "); */
37 __RCSID("$NetBSD: nfs_clkrpc.c,v 1.3 2024/07/05 04:31:52 rin 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 m_freem(nd.nd_mrep);
120
121 if (nd.nd_cred != NULL)
122 crfree(nd.nd_cred);
123
124 if (cacherep == RC_DROPIT) {
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 m_freem(nd.nd_mreq);
139 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq))
140 svcerr_systemerr(rqst);
141 else
142 NFSCL_DEBUG(1, "cbrep sent\n");
143 svc_freereq(rqst);
144 }
145
146 /*
147 * Check the cache and, optionally, do the RPC.
148 * Return the appropriate cache response.
149 */
150 static int
nfs_cbproc(struct nfsrv_descript * nd,u_int32_t xid)151 nfs_cbproc(struct nfsrv_descript *nd, u_int32_t xid)
152 {
153 struct thread *td = curthread;
154 int cacherep;
155
156 if (nd->nd_nam2 == NULL)
157 nd->nd_flag |= ND_STREAMSOCK;
158
159 nfscl_docb(nd, td);
160 if (nd->nd_repstat == NFSERR_DONTREPLY)
161 cacherep = RC_DROPIT;
162 else
163 cacherep = RC_REPLY;
164 return (cacherep);
165 }
166
167 /*
168 * Adds a socket to the list for servicing by nfscbds.
169 */
170 int
nfscbd_addsock(struct file * fp)171 nfscbd_addsock(struct file *fp)
172 {
173 int siz;
174 struct socket *so;
175 int error;
176 SVCXPRT *xprt;
177
178 so = fp->f_data;
179
180 siz = sb_max_adj;
181 error = soreserve(so, siz, siz);
182 if (error)
183 return (error);
184
185 /*
186 * Steal the socket from userland so that it doesn't close
187 * unexpectedly.
188 */
189 if (so->so_type == SOCK_DGRAM)
190 xprt = svc_dg_create(nfscbd_pool, so, 0, 0);
191 else
192 xprt = svc_vc_create(nfscbd_pool, so, 0, 0);
193 if (xprt) {
194 fp->f_ops = &badfileops;
195 fp->f_data = NULL;
196 svc_reg(xprt, NFS_CALLBCKPROG, NFSV4_CBVERS, nfscb_program,
197 NULL);
198 SVC_RELEASE(xprt);
199 }
200
201 return (0);
202 }
203
204 /*
205 * Called by nfssvc() for nfscbds. Just loops around servicing rpc requests
206 * until it is killed by a signal.
207 *
208 * For now, only support callbacks via RPCSEC_GSS if there is a KerberosV
209 * keytab entry with a host based entry in it on the client. (I'm not even
210 * sure that getting Acceptor credentials for a user principal with a
211 * credentials cache is possible, but even if it is, major changes to the
212 * kgssapi would be required.)
213 * I don't believe that this is a serious limitation since, as of 2009, most
214 * NFSv4 servers supporting callbacks are using AUTH_SYS for callbacks even
215 * when the client is using RPCSEC_GSS. (This BSD server uses AUTH_SYS
216 * for callbacks unless nfsrv_gsscallbackson is set non-zero.)
217 */
218 int
nfscbd_nfsd(struct thread * td,struct nfsd_nfscbd_args * args)219 nfscbd_nfsd(struct thread *td, struct nfsd_nfscbd_args *args)
220 {
221 char principal[128];
222 int error;
223
224 if (args != NULL) {
225 error = copyinstr(args->principal, principal,
226 sizeof(principal), NULL);
227 if (error)
228 return (error);
229 } else {
230 principal[0] = '\0';
231 }
232
233 /*
234 * Only the first nfsd actually does any work. The RPC code
235 * adds threads to it as needed. Any extra processes offered
236 * by nfsd just exit. If nfsd is new enough, it will call us
237 * once with a structure that specifies how many threads to
238 * use.
239 */
240 NFSD_LOCK();
241 if (nfs_numnfscbd == 0) {
242 nfs_numnfscbd++;
243
244 NFSD_UNLOCK();
245
246 if (principal[0] != '\0')
247 rpc_gss_set_svc_name_call(principal, "kerberosv5",
248 GSS_C_INDEFINITE, NFS_CALLBCKPROG, NFSV4_CBVERS);
249
250 nfscbd_pool->sp_minthreads = 4;
251 nfscbd_pool->sp_maxthreads = 4;
252
253 svc_run(nfscbd_pool);
254
255 rpc_gss_clear_svc_name_call(NFS_CALLBCKPROG, NFSV4_CBVERS);
256
257 NFSD_LOCK();
258 nfs_numnfscbd--;
259 nfsrvd_cbinit(1);
260 }
261 NFSD_UNLOCK();
262
263 return (0);
264 }
265
266 /*
267 * Initialize the data structures for the server.
268 * Handshake with any new nfsds starting up to avoid any chance of
269 * corruption.
270 */
271 void
nfsrvd_cbinit(int terminating)272 nfsrvd_cbinit(int terminating)
273 {
274
275 NFSD_LOCK_ASSERT();
276
277 if (terminating) {
278 /* Wait for any xprt registrations to complete. */
279 while (nfs_numnfscbd > 0)
280 msleep(&nfs_numnfscbd, NFSDLOCKMUTEXPTR, PZERO,
281 "nfscbdt", 0);
282 }
283
284 if (nfscbd_pool == NULL) {
285 NFSD_UNLOCK();
286 nfscbd_pool = svcpool_create("nfscbd", NULL);
287 nfscbd_pool->sp_rcache = NULL;
288 nfscbd_pool->sp_assign = NULL;
289 nfscbd_pool->sp_done = NULL;
290 NFSD_LOCK();
291 }
292 }
293
294