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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/nfs/callback.c
4 *
5 * Copyright (C) 2004 Trond Myklebust
6 *
7 * NFSv4 callback handling
8 */
9
10#include <linux/completion.h>
11#include <linux/ip.h>
12#include <linux/module.h>
13#include <linux/sched/signal.h>
14#include <linux/sunrpc/svc.h>
15#include <linux/sunrpc/svcsock.h>
16#include <linux/nfs_fs.h>
17#include <linux/errno.h>
18#include <linux/mutex.h>
19#include <linux/freezer.h>
20#include <linux/sunrpc/svcauth_gss.h>
21#include <linux/sunrpc/bc_xprt.h>
22
23#include <net/inet_sock.h>
24
25#include "nfs4_fs.h"
26#include "callback.h"
27#include "internal.h"
28#include "netns.h"
29
30#define NFSDBG_FACILITY NFSDBG_CALLBACK
31
32struct nfs_callback_data {
33 unsigned int users;
34 struct svc_serv *serv;
35};
36
37static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
38static DEFINE_MUTEX(nfs_callback_mutex);
39static struct svc_program nfs4_callback_program;
40
41static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
42{
43 const struct cred *cred = current_cred();
44 int ret;
45 struct nfs_net *nn = net_generic(net, nfs_net_id);
46
47 ret = svc_xprt_create(serv, "tcp", net, PF_INET,
48 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS,
49 cred);
50 if (ret <= 0)
51 goto out_err;
52 nn->nfs_callback_tcpport = ret;
53 dprintk("NFS: Callback listener port = %u (af %u, net %x)\n",
54 nn->nfs_callback_tcpport, PF_INET, net->ns.inum);
55
56 ret = svc_xprt_create(serv, "tcp", net, PF_INET6,
57 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS,
58 cred);
59 if (ret > 0) {
60 nn->nfs_callback_tcpport6 = ret;
61 dprintk("NFS: Callback listener port = %u (af %u, net %x)\n",
62 nn->nfs_callback_tcpport6, PF_INET6, net->ns.inum);
63 } else if (ret != -EAFNOSUPPORT)
64 goto out_err;
65 return 0;
66
67out_err:
68 return (ret) ? ret : -ENOMEM;
69}
70
71/*
72 * This is the NFSv4 callback kernel thread.
73 */
74static int
75nfs4_callback_svc(void *vrqstp)
76{
77 int err;
78 struct svc_rqst *rqstp = vrqstp;
79
80 set_freezable();
81
82 while (!kthread_freezable_should_stop(NULL)) {
83
84 if (signal_pending(current))
85 flush_signals(current);
86 /*
87 * Listen for a request on the socket
88 */
89 err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT);
90 if (err == -EAGAIN || err == -EINTR)
91 continue;
92 svc_process(rqstp);
93 }
94
95 svc_exit_thread(rqstp);
96 return 0;
97}
98
99#if defined(CONFIG_NFS_V4_1)
100/*
101 * The callback service for NFSv4.1 callbacks
102 */
103static int
104nfs41_callback_svc(void *vrqstp)
105{
106 struct svc_rqst *rqstp = vrqstp;
107 struct svc_serv *serv = rqstp->rq_server;
108 struct rpc_rqst *req;
109 int error;
110 DEFINE_WAIT(wq);
111
112 set_freezable();
113
114 while (!kthread_freezable_should_stop(NULL)) {
115
116 if (signal_pending(current))
117 flush_signals(current);
118
119 prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
120 spin_lock_bh(&serv->sv_cb_lock);
121 if (!list_empty(&serv->sv_cb_list)) {
122 req = list_first_entry(&serv->sv_cb_list,
123 struct rpc_rqst, rq_bc_list);
124 list_del(&req->rq_bc_list);
125 spin_unlock_bh(&serv->sv_cb_lock);
126 finish_wait(&serv->sv_cb_waitq, &wq);
127 dprintk("Invoking bc_svc_process()\n");
128 error = bc_svc_process(serv, req, rqstp);
129 dprintk("bc_svc_process() returned w/ error code= %d\n",
130 error);
131 } else {
132 spin_unlock_bh(&serv->sv_cb_lock);
133 if (!kthread_should_stop())
134 schedule();
135 finish_wait(&serv->sv_cb_waitq, &wq);
136 }
137 }
138
139 svc_exit_thread(rqstp);
140 return 0;
141}
142
143static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
144 struct svc_serv *serv)
145{
146 if (minorversion)
147 /*
148 * Save the svc_serv in the transport so that it can
149 * be referenced when the session backchannel is initialized
150 */
151 xprt->bc_serv = serv;
152}
153#else
154static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
155 struct svc_serv *serv)
156{
157}
158#endif /* CONFIG_NFS_V4_1 */
159
160static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
161 struct svc_serv *serv)
162{
163 int nrservs = nfs_callback_nr_threads;
164 int ret;
165
166 nfs_callback_bc_serv(minorversion, xprt, serv);
167
168 if (nrservs < NFS4_MIN_NR_CALLBACK_THREADS)
169 nrservs = NFS4_MIN_NR_CALLBACK_THREADS;
170
171 if (serv->sv_nrthreads == nrservs)
172 return 0;
173
174 ret = svc_set_num_threads(serv, NULL, nrservs);
175 if (ret) {
176 svc_set_num_threads(serv, NULL, 0);
177 return ret;
178 }
179 dprintk("nfs_callback_up: service started\n");
180 return 0;
181}
182
183static void nfs_callback_down_net(u32 minorversion, struct svc_serv *serv, struct net *net)
184{
185 struct nfs_net *nn = net_generic(net, nfs_net_id);
186
187 if (--nn->cb_users[minorversion])
188 return;
189
190 dprintk("NFS: destroy per-net callback data; net=%x\n", net->ns.inum);
191 svc_xprt_destroy_all(serv, net);
192}
193
194static int nfs_callback_up_net(int minorversion, struct svc_serv *serv,
195 struct net *net, struct rpc_xprt *xprt)
196{
197 struct nfs_net *nn = net_generic(net, nfs_net_id);
198 int ret;
199
200 if (nn->cb_users[minorversion]++)
201 return 0;
202
203 dprintk("NFS: create per-net callback data; net=%x\n", net->ns.inum);
204
205 ret = svc_bind(serv, net);
206 if (ret < 0) {
207 printk(KERN_WARNING "NFS: bind callback service failed\n");
208 goto err_bind;
209 }
210
211 ret = 0;
212 if (!IS_ENABLED(CONFIG_NFS_V4_1) || minorversion == 0)
213 ret = nfs4_callback_up_net(serv, net);
214 else if (xprt->ops->bc_setup)
215 set_bc_enabled(serv);
216 else
217 ret = -EPROTONOSUPPORT;
218
219 if (ret < 0) {
220 printk(KERN_ERR "NFS: callback service start failed\n");
221 goto err_socks;
222 }
223 return 0;
224
225err_socks:
226 svc_rpcb_cleanup(serv, net);
227err_bind:
228 nn->cb_users[minorversion]--;
229 dprintk("NFS: Couldn't create callback socket: err = %d; "
230 "net = %x\n", ret, net->ns.inum);
231 return ret;
232}
233
234static struct svc_serv *nfs_callback_create_svc(int minorversion)
235{
236 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
237 int (*threadfn)(void *data);
238 struct svc_serv *serv;
239
240 /*
241 * Check whether we're already up and running.
242 */
243 if (cb_info->serv)
244 return svc_get(cb_info->serv);
245
246 /*
247 * Sanity check: if there's no task,
248 * we should be the first user ...
249 */
250 if (cb_info->users)
251 printk(KERN_WARNING "nfs_callback_create_svc: no kthread, %d users??\n",
252 cb_info->users);
253
254 threadfn = nfs4_callback_svc;
255#if defined(CONFIG_NFS_V4_1)
256 if (minorversion)
257 threadfn = nfs41_callback_svc;
258#else
259 if (minorversion)
260 return ERR_PTR(-ENOTSUPP);
261#endif
262 serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE,
263 threadfn);
264 if (!serv) {
265 printk(KERN_ERR "nfs_callback_create_svc: create service failed\n");
266 return ERR_PTR(-ENOMEM);
267 }
268 cb_info->serv = serv;
269 /* As there is only one thread we need to over-ride the
270 * default maximum of 80 connections
271 */
272 serv->sv_maxconn = 1024;
273 dprintk("nfs_callback_create_svc: service created\n");
274 return serv;
275}
276
277/*
278 * Bring up the callback thread if it is not already up.
279 */
280int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
281{
282 struct svc_serv *serv;
283 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
284 int ret;
285 struct net *net = xprt->xprt_net;
286
287 mutex_lock(&nfs_callback_mutex);
288
289 serv = nfs_callback_create_svc(minorversion);
290 if (IS_ERR(serv)) {
291 ret = PTR_ERR(serv);
292 goto err_create;
293 }
294
295 ret = nfs_callback_up_net(minorversion, serv, net, xprt);
296 if (ret < 0)
297 goto err_net;
298
299 ret = nfs_callback_start_svc(minorversion, xprt, serv);
300 if (ret < 0)
301 goto err_start;
302
303 cb_info->users++;
304err_net:
305 if (!cb_info->users)
306 cb_info->serv = NULL;
307 svc_put(serv);
308err_create:
309 mutex_unlock(&nfs_callback_mutex);
310 return ret;
311
312err_start:
313 nfs_callback_down_net(minorversion, serv, net);
314 dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
315 goto err_net;
316}
317
318/*
319 * Kill the callback thread if it's no longer being used.
320 */
321void nfs_callback_down(int minorversion, struct net *net)
322{
323 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
324 struct svc_serv *serv;
325
326 mutex_lock(&nfs_callback_mutex);
327 serv = cb_info->serv;
328 nfs_callback_down_net(minorversion, serv, net);
329 cb_info->users--;
330 if (cb_info->users == 0) {
331 svc_get(serv);
332 svc_set_num_threads(serv, NULL, 0);
333 svc_put(serv);
334 dprintk("nfs_callback_down: service destroyed\n");
335 cb_info->serv = NULL;
336 }
337 mutex_unlock(&nfs_callback_mutex);
338}
339
340/* Boolean check of RPC_AUTH_GSS principal */
341int
342check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp)
343{
344 char *p = rqstp->rq_cred.cr_principal;
345
346 if (rqstp->rq_authop->flavour != RPC_AUTH_GSS)
347 return 1;
348
349 /* No RPC_AUTH_GSS on NFSv4.1 back channel yet */
350 if (clp->cl_minorversion != 0)
351 return 0;
352 /*
353 * It might just be a normal user principal, in which case
354 * userspace won't bother to tell us the name at all.
355 */
356 if (p == NULL)
357 return 0;
358
359 /*
360 * Did we get the acceptor from userland during the SETCLIENID
361 * negotiation?
362 */
363 if (clp->cl_acceptor)
364 return !strcmp(p, clp->cl_acceptor);
365
366 /*
367 * Otherwise try to verify it using the cl_hostname. Note that this
368 * doesn't work if a non-canonical hostname was used in the devname.
369 */
370
371 /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
372
373 if (memcmp(p, "nfs@", 4) != 0)
374 return 0;
375 p += 4;
376 if (strcmp(p, clp->cl_hostname) != 0)
377 return 0;
378 return 1;
379}
380
381/*
382 * pg_authenticate method for nfsv4 callback threads.
383 *
384 * The authflavor has been negotiated, so an incorrect flavor is a server
385 * bug. Deny packets with incorrect authflavor.
386 *
387 * All other checking done after NFS decoding where the nfs_client can be
388 * found in nfs4_callback_compound
389 */
390static int nfs_callback_authenticate(struct svc_rqst *rqstp)
391{
392 rqstp->rq_auth_stat = rpc_autherr_badcred;
393
394 switch (rqstp->rq_authop->flavour) {
395 case RPC_AUTH_NULL:
396 if (rqstp->rq_proc != CB_NULL)
397 return SVC_DENIED;
398 break;
399 case RPC_AUTH_GSS:
400 /* No RPC_AUTH_GSS support yet in NFSv4.1 */
401 if (svc_is_backchannel(rqstp))
402 return SVC_DENIED;
403 }
404
405 rqstp->rq_auth_stat = rpc_auth_ok;
406 return SVC_OK;
407}
408
409/*
410 * Define NFS4 callback program
411 */
412static const struct svc_version *nfs4_callback_version[] = {
413 [1] = &nfs4_callback_version1,
414 [4] = &nfs4_callback_version4,
415};
416
417static struct svc_stat nfs4_callback_stats;
418
419static struct svc_program nfs4_callback_program = {
420 .pg_prog = NFS4_CALLBACK, /* RPC service number */
421 .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
422 .pg_vers = nfs4_callback_version, /* version table */
423 .pg_name = "NFSv4 callback", /* service name */
424 .pg_class = "nfs", /* authentication class */
425 .pg_stats = &nfs4_callback_stats,
426 .pg_authenticate = nfs_callback_authenticate,
427 .pg_init_request = svc_generic_init_request,
428 .pg_rpcbind_set = svc_generic_rpcbind_set,
429};
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/nfs/callback.c
4 *
5 * Copyright (C) 2004 Trond Myklebust
6 *
7 * NFSv4 callback handling
8 */
9
10#include <linux/completion.h>
11#include <linux/ip.h>
12#include <linux/module.h>
13#include <linux/sched/signal.h>
14#include <linux/sunrpc/svc.h>
15#include <linux/sunrpc/svcsock.h>
16#include <linux/nfs_fs.h>
17#include <linux/errno.h>
18#include <linux/mutex.h>
19#include <linux/freezer.h>
20#include <linux/sunrpc/svcauth_gss.h>
21#include <linux/sunrpc/bc_xprt.h>
22
23#include <net/inet_sock.h>
24
25#include "nfs4_fs.h"
26#include "callback.h"
27#include "internal.h"
28#include "netns.h"
29
30#define NFSDBG_FACILITY NFSDBG_CALLBACK
31
32struct nfs_callback_data {
33 unsigned int users;
34 struct svc_serv *serv;
35};
36
37static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
38static DEFINE_MUTEX(nfs_callback_mutex);
39static struct svc_program nfs4_callback_program;
40
41static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
42{
43 const struct cred *cred = current_cred();
44 int ret;
45 struct nfs_net *nn = net_generic(net, nfs_net_id);
46
47 ret = svc_xprt_create(serv, "tcp", net, PF_INET,
48 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS,
49 cred);
50 if (ret <= 0)
51 goto out_err;
52 nn->nfs_callback_tcpport = ret;
53 dprintk("NFS: Callback listener port = %u (af %u, net %x)\n",
54 nn->nfs_callback_tcpport, PF_INET, net->ns.inum);
55
56 ret = svc_xprt_create(serv, "tcp", net, PF_INET6,
57 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS,
58 cred);
59 if (ret > 0) {
60 nn->nfs_callback_tcpport6 = ret;
61 dprintk("NFS: Callback listener port = %u (af %u, net %x)\n",
62 nn->nfs_callback_tcpport6, PF_INET6, net->ns.inum);
63 } else if (ret != -EAFNOSUPPORT)
64 goto out_err;
65 return 0;
66
67out_err:
68 return (ret) ? ret : -ENOMEM;
69}
70
71/*
72 * This is the NFSv4 callback kernel thread.
73 */
74static int
75nfs4_callback_svc(void *vrqstp)
76{
77 struct svc_rqst *rqstp = vrqstp;
78
79 svc_thread_init_status(rqstp, 0);
80
81 set_freezable();
82
83 while (!svc_thread_should_stop(rqstp))
84 svc_recv(rqstp);
85
86 svc_exit_thread(rqstp);
87 return 0;
88}
89
90#if defined(CONFIG_NFS_V4_1)
91static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
92 struct svc_serv *serv)
93{
94 if (minorversion)
95 /*
96 * Save the svc_serv in the transport so that it can
97 * be referenced when the session backchannel is initialized
98 */
99 xprt->bc_serv = serv;
100}
101#else
102static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
103 struct svc_serv *serv)
104{
105}
106#endif /* CONFIG_NFS_V4_1 */
107
108static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
109 struct svc_serv *serv)
110{
111 int nrservs = nfs_callback_nr_threads;
112 int ret;
113
114 nfs_callback_bc_serv(minorversion, xprt, serv);
115
116 if (nrservs < NFS4_MIN_NR_CALLBACK_THREADS)
117 nrservs = NFS4_MIN_NR_CALLBACK_THREADS;
118
119 if (serv->sv_nrthreads == nrservs)
120 return 0;
121
122 ret = svc_set_num_threads(serv, NULL, nrservs);
123 if (ret) {
124 svc_set_num_threads(serv, NULL, 0);
125 return ret;
126 }
127 dprintk("nfs_callback_up: service started\n");
128 return 0;
129}
130
131static void nfs_callback_down_net(u32 minorversion, struct svc_serv *serv, struct net *net)
132{
133 struct nfs_net *nn = net_generic(net, nfs_net_id);
134
135 if (--nn->cb_users[minorversion])
136 return;
137
138 dprintk("NFS: destroy per-net callback data; net=%x\n", net->ns.inum);
139 svc_xprt_destroy_all(serv, net);
140}
141
142static int nfs_callback_up_net(int minorversion, struct svc_serv *serv,
143 struct net *net, struct rpc_xprt *xprt)
144{
145 struct nfs_net *nn = net_generic(net, nfs_net_id);
146 int ret;
147
148 if (nn->cb_users[minorversion]++)
149 return 0;
150
151 dprintk("NFS: create per-net callback data; net=%x\n", net->ns.inum);
152
153 ret = svc_bind(serv, net);
154 if (ret < 0) {
155 printk(KERN_WARNING "NFS: bind callback service failed\n");
156 goto err_bind;
157 }
158
159 ret = 0;
160 if (!IS_ENABLED(CONFIG_NFS_V4_1) || minorversion == 0)
161 ret = nfs4_callback_up_net(serv, net);
162 else if (xprt->ops->bc_setup)
163 set_bc_enabled(serv);
164 else
165 ret = -EPROTONOSUPPORT;
166
167 if (ret < 0) {
168 printk(KERN_ERR "NFS: callback service start failed\n");
169 goto err_socks;
170 }
171 return 0;
172
173err_socks:
174 svc_rpcb_cleanup(serv, net);
175err_bind:
176 nn->cb_users[minorversion]--;
177 dprintk("NFS: Couldn't create callback socket: err = %d; "
178 "net = %x\n", ret, net->ns.inum);
179 return ret;
180}
181
182static struct svc_serv *nfs_callback_create_svc(int minorversion)
183{
184 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
185 int (*threadfn)(void *data);
186 struct svc_serv *serv;
187
188 /*
189 * Check whether we're already up and running.
190 */
191 if (cb_info->serv)
192 return cb_info->serv;
193
194 /*
195 * Sanity check: if there's no task,
196 * we should be the first user ...
197 */
198 if (cb_info->users)
199 printk(KERN_WARNING "nfs_callback_create_svc: no kthread, %d users??\n",
200 cb_info->users);
201
202 threadfn = nfs4_callback_svc;
203#if !defined(CONFIG_NFS_V4_1)
204 if (minorversion)
205 return ERR_PTR(-ENOTSUPP);
206#endif
207 serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE,
208 threadfn);
209 if (!serv) {
210 printk(KERN_ERR "nfs_callback_create_svc: create service failed\n");
211 return ERR_PTR(-ENOMEM);
212 }
213 cb_info->serv = serv;
214 /* As there is only one thread we need to over-ride the
215 * default maximum of 80 connections
216 */
217 serv->sv_maxconn = 1024;
218 dprintk("nfs_callback_create_svc: service created\n");
219 return serv;
220}
221
222/*
223 * Bring up the callback thread if it is not already up.
224 */
225int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
226{
227 struct svc_serv *serv;
228 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
229 int ret;
230 struct net *net = xprt->xprt_net;
231
232 mutex_lock(&nfs_callback_mutex);
233
234 serv = nfs_callback_create_svc(minorversion);
235 if (IS_ERR(serv)) {
236 ret = PTR_ERR(serv);
237 goto err_create;
238 }
239
240 ret = nfs_callback_up_net(minorversion, serv, net, xprt);
241 if (ret < 0)
242 goto err_net;
243
244 ret = nfs_callback_start_svc(minorversion, xprt, serv);
245 if (ret < 0)
246 goto err_start;
247
248 cb_info->users++;
249err_net:
250 if (!cb_info->users) {
251 svc_set_num_threads(cb_info->serv, NULL, 0);
252 svc_destroy(&cb_info->serv);
253 }
254err_create:
255 mutex_unlock(&nfs_callback_mutex);
256 return ret;
257
258err_start:
259 nfs_callback_down_net(minorversion, serv, net);
260 dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
261 goto err_net;
262}
263
264/*
265 * Kill the callback thread if it's no longer being used.
266 */
267void nfs_callback_down(int minorversion, struct net *net)
268{
269 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
270 struct svc_serv *serv;
271
272 mutex_lock(&nfs_callback_mutex);
273 serv = cb_info->serv;
274 nfs_callback_down_net(minorversion, serv, net);
275 cb_info->users--;
276 if (cb_info->users == 0) {
277 svc_set_num_threads(serv, NULL, 0);
278 dprintk("nfs_callback_down: service destroyed\n");
279 svc_destroy(&cb_info->serv);
280 }
281 mutex_unlock(&nfs_callback_mutex);
282}
283
284/* Boolean check of RPC_AUTH_GSS principal */
285int
286check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp)
287{
288 char *p = rqstp->rq_cred.cr_principal;
289
290 if (rqstp->rq_authop->flavour != RPC_AUTH_GSS)
291 return 1;
292
293 /* No RPC_AUTH_GSS on NFSv4.1 back channel yet */
294 if (clp->cl_minorversion != 0)
295 return 0;
296 /*
297 * It might just be a normal user principal, in which case
298 * userspace won't bother to tell us the name at all.
299 */
300 if (p == NULL)
301 return 0;
302
303 /*
304 * Did we get the acceptor from userland during the SETCLIENID
305 * negotiation?
306 */
307 if (clp->cl_acceptor)
308 return !strcmp(p, clp->cl_acceptor);
309
310 /*
311 * Otherwise try to verify it using the cl_hostname. Note that this
312 * doesn't work if a non-canonical hostname was used in the devname.
313 */
314
315 /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
316
317 if (memcmp(p, "nfs@", 4) != 0)
318 return 0;
319 p += 4;
320 if (strcmp(p, clp->cl_hostname) != 0)
321 return 0;
322 return 1;
323}
324
325/*
326 * pg_authenticate method for nfsv4 callback threads.
327 *
328 * The authflavor has been negotiated, so an incorrect flavor is a server
329 * bug. Deny packets with incorrect authflavor.
330 *
331 * All other checking done after NFS decoding where the nfs_client can be
332 * found in nfs4_callback_compound
333 */
334static enum svc_auth_status nfs_callback_authenticate(struct svc_rqst *rqstp)
335{
336 rqstp->rq_auth_stat = rpc_autherr_badcred;
337
338 switch (rqstp->rq_authop->flavour) {
339 case RPC_AUTH_NULL:
340 if (rqstp->rq_proc != CB_NULL)
341 return SVC_DENIED;
342 break;
343 case RPC_AUTH_GSS:
344 /* No RPC_AUTH_GSS support yet in NFSv4.1 */
345 if (svc_is_backchannel(rqstp))
346 return SVC_DENIED;
347 }
348
349 rqstp->rq_auth_stat = rpc_auth_ok;
350 return SVC_OK;
351}
352
353/*
354 * Define NFS4 callback program
355 */
356static const struct svc_version *nfs4_callback_version[] = {
357 [1] = &nfs4_callback_version1,
358 [4] = &nfs4_callback_version4,
359};
360
361static struct svc_program nfs4_callback_program = {
362 .pg_prog = NFS4_CALLBACK, /* RPC service number */
363 .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
364 .pg_vers = nfs4_callback_version, /* version table */
365 .pg_name = "NFSv4 callback", /* service name */
366 .pg_class = "nfs", /* authentication class */
367 .pg_authenticate = nfs_callback_authenticate,
368 .pg_init_request = svc_generic_init_request,
369 .pg_rpcbind_set = svc_generic_rpcbind_set,
370};