2 * linux/fs/nfs/callback.c
4 * Copyright (C) 2004 Trond Myklebust
6 * NFSv4 callback handling
9 #include <linux/completion.h>
11 #include <linux/module.h>
12 #include <linux/sunrpc/svc.h>
13 #include <linux/sunrpc/svcsock.h>
14 #include <linux/nfs_fs.h>
15 #include <linux/errno.h>
16 #include <linux/mutex.h>
17 #include <linux/freezer.h>
18 #include <linux/kthread.h>
19 #include <linux/sunrpc/svcauth_gss.h>
20 #include <linux/sunrpc/bc_xprt.h>
22 #include <net/inet_sock.h>
29 #define NFSDBG_FACILITY NFSDBG_CALLBACK
31 struct nfs_callback_data {
33 struct svc_serv *serv;
34 struct svc_rqst *rqst;
35 struct task_struct *task;
38 static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
39 static DEFINE_MUTEX(nfs_callback_mutex);
40 static struct svc_program nfs4_callback_program;
42 static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
45 struct nfs_net *nn = net_generic(net, nfs_net_id);
47 ret = svc_create_xprt(serv, "tcp", net, PF_INET,
48 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
51 nn->nfs_callback_tcpport = ret;
52 dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
53 nn->nfs_callback_tcpport, PF_INET, net);
55 ret = svc_create_xprt(serv, "tcp", net, PF_INET6,
56 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
58 nn->nfs_callback_tcpport6 = ret;
59 dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
60 nn->nfs_callback_tcpport6, PF_INET6, net);
61 } else if (ret != -EAFNOSUPPORT)
66 return (ret) ? ret : -ENOMEM;
70 * This is the NFSv4 callback kernel thread.
73 nfs4_callback_svc(void *vrqstp)
76 struct svc_rqst *rqstp = vrqstp;
80 while (!kthread_should_stop()) {
82 * Listen for a request on the socket
84 err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT);
85 if (err == -EAGAIN || err == -EINTR)
93 * Prepare to bring up the NFSv4 callback service
95 static struct svc_rqst *
96 nfs4_callback_up(struct svc_serv *serv)
98 return svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
101 #if defined(CONFIG_NFS_V4_1)
103 * The callback service for NFSv4.1 callbacks
106 nfs41_callback_svc(void *vrqstp)
108 struct svc_rqst *rqstp = vrqstp;
109 struct svc_serv *serv = rqstp->rq_server;
110 struct rpc_rqst *req;
116 while (!kthread_should_stop()) {
120 prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
121 spin_lock_bh(&serv->sv_cb_lock);
122 if (!list_empty(&serv->sv_cb_list)) {
123 req = list_first_entry(&serv->sv_cb_list,
124 struct rpc_rqst, rq_bc_list);
125 list_del(&req->rq_bc_list);
126 spin_unlock_bh(&serv->sv_cb_lock);
127 finish_wait(&serv->sv_cb_waitq, &wq);
128 dprintk("Invoking bc_svc_process()\n");
129 error = bc_svc_process(serv, req, rqstp);
130 dprintk("bc_svc_process() returned w/ error code= %d\n",
133 spin_unlock_bh(&serv->sv_cb_lock);
135 finish_wait(&serv->sv_cb_waitq, &wq);
137 flush_signals(current);
143 * Bring up the NFSv4.1 callback service
145 static struct svc_rqst *
146 nfs41_callback_up(struct svc_serv *serv)
148 struct svc_rqst *rqstp;
150 rqstp = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
151 dprintk("--> %s return %d\n", __func__, PTR_ERR_OR_ZERO(rqstp));
155 static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
156 struct svc_serv *serv)
160 * Save the svc_serv in the transport so that it can
161 * be referenced when the session backchannel is initialized
163 xprt->bc_serv = serv;
166 static struct svc_rqst *
167 nfs41_callback_up(struct svc_serv *serv)
169 return ERR_PTR(-ENOTSUPP);
172 static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
173 struct svc_serv *serv)
176 #endif /* CONFIG_NFS_V4_1 */
178 static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
179 struct svc_serv *serv)
181 struct svc_rqst *rqstp;
182 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
185 nfs_callback_bc_serv(minorversion, xprt, serv);
190 switch (minorversion) {
192 /* v4.0 callback setup */
193 rqstp = nfs4_callback_up(serv);
196 rqstp = nfs41_callback_up(serv);
200 return PTR_ERR(rqstp);
202 svc_sock_update_bufs(serv);
204 cb_info->rqst = rqstp;
205 cb_info->task = kthread_create(serv->sv_ops->svo_function,
207 "nfsv4.%u-svc", minorversion);
208 if (IS_ERR(cb_info->task)) {
209 ret = PTR_ERR(cb_info->task);
210 svc_exit_thread(cb_info->rqst);
211 cb_info->rqst = NULL;
212 cb_info->task = NULL;
215 rqstp->rq_task = cb_info->task;
216 wake_up_process(cb_info->task);
217 dprintk("nfs_callback_up: service started\n");
221 static void nfs_callback_down_net(u32 minorversion, struct svc_serv *serv, struct net *net)
223 struct nfs_net *nn = net_generic(net, nfs_net_id);
225 if (--nn->cb_users[minorversion])
228 dprintk("NFS: destroy per-net callback data; net=%p\n", net);
229 svc_shutdown_net(serv, net);
232 static int nfs_callback_up_net(int minorversion, struct svc_serv *serv,
233 struct net *net, struct rpc_xprt *xprt)
235 struct nfs_net *nn = net_generic(net, nfs_net_id);
238 if (nn->cb_users[minorversion]++)
241 dprintk("NFS: create per-net callback data; net=%p\n", net);
243 ret = svc_bind(serv, net);
245 printk(KERN_WARNING "NFS: bind callback service failed\n");
249 ret = -EPROTONOSUPPORT;
250 if (minorversion == 0)
251 ret = nfs4_callback_up_net(serv, net);
252 else if (xprt->ops->bc_up)
253 ret = xprt->ops->bc_up(serv, net);
256 printk(KERN_ERR "NFS: callback service start failed\n");
262 svc_rpcb_cleanup(serv, net);
264 nn->cb_users[minorversion]--;
265 dprintk("NFS: Couldn't create callback socket: err = %d; "
266 "net = %p\n", ret, net);
270 static struct svc_serv_ops nfs40_cb_sv_ops = {
271 .svo_function = nfs4_callback_svc,
272 .svo_enqueue_xprt = svc_xprt_do_enqueue,
273 .svo_module = THIS_MODULE,
275 #if defined(CONFIG_NFS_V4_1)
276 static struct svc_serv_ops nfs41_cb_sv_ops = {
277 .svo_function = nfs41_callback_svc,
278 .svo_enqueue_xprt = svc_xprt_do_enqueue,
279 .svo_module = THIS_MODULE,
282 struct svc_serv_ops *nfs4_cb_sv_ops[] = {
283 [0] = &nfs40_cb_sv_ops,
284 [1] = &nfs41_cb_sv_ops,
287 struct svc_serv_ops *nfs4_cb_sv_ops[] = {
288 [0] = &nfs40_cb_sv_ops,
293 static struct svc_serv *nfs_callback_create_svc(int minorversion)
295 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
296 struct svc_serv *serv;
297 struct svc_serv_ops *sv_ops;
300 * Check whether we're already up and running.
304 * Note: increase service usage, because later in case of error
305 * svc_destroy() will be called.
307 svc_get(cb_info->serv);
308 return cb_info->serv;
311 switch (minorversion) {
313 sv_ops = nfs4_cb_sv_ops[0];
316 sv_ops = nfs4_cb_sv_ops[1];
320 return ERR_PTR(-ENOTSUPP);
323 * Sanity check: if there's no task,
324 * we should be the first user ...
327 printk(KERN_WARNING "nfs_callback_create_svc: no kthread, %d users??\n",
330 serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, sv_ops);
332 printk(KERN_ERR "nfs_callback_create_svc: create service failed\n");
333 return ERR_PTR(-ENOMEM);
335 cb_info->serv = serv;
336 /* As there is only one thread we need to over-ride the
337 * default maximum of 80 connections
339 serv->sv_maxconn = 1024;
340 dprintk("nfs_callback_create_svc: service created\n");
345 * Bring up the callback thread if it is not already up.
347 int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
349 struct svc_serv *serv;
350 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
352 struct net *net = xprt->xprt_net;
354 mutex_lock(&nfs_callback_mutex);
356 serv = nfs_callback_create_svc(minorversion);
362 ret = nfs_callback_up_net(minorversion, serv, net, xprt);
366 ret = nfs_callback_start_svc(minorversion, xprt, serv);
372 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
373 * svc_prepare_thread increments that. So we need to call svc_destroy
374 * on both success and failure so that the refcount is 1 when the
379 cb_info->serv = NULL;
382 mutex_unlock(&nfs_callback_mutex);
386 nfs_callback_down_net(minorversion, serv, net);
387 dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
392 * Kill the callback thread if it's no longer being used.
394 void nfs_callback_down(int minorversion, struct net *net)
396 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
398 mutex_lock(&nfs_callback_mutex);
399 nfs_callback_down_net(minorversion, cb_info->serv, net);
401 if (cb_info->users == 0) {
402 if (cb_info->task != NULL) {
403 kthread_stop(cb_info->task);
404 dprintk("nfs_callback_down: service stopped\n");
406 svc_exit_thread(cb_info->rqst);
407 dprintk("nfs_callback_down: service destroyed\n");
408 cb_info->serv = NULL;
409 cb_info->rqst = NULL;
410 cb_info->task = NULL;
412 mutex_unlock(&nfs_callback_mutex);
415 /* Boolean check of RPC_AUTH_GSS principal */
417 check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp)
419 char *p = rqstp->rq_cred.cr_principal;
421 if (rqstp->rq_authop->flavour != RPC_AUTH_GSS)
424 /* No RPC_AUTH_GSS on NFSv4.1 back channel yet */
425 if (clp->cl_minorversion != 0)
428 * It might just be a normal user principal, in which case
429 * userspace won't bother to tell us the name at all.
435 * Did we get the acceptor from userland during the SETCLIENID
438 if (clp->cl_acceptor)
439 return !strcmp(p, clp->cl_acceptor);
442 * Otherwise try to verify it using the cl_hostname. Note that this
443 * doesn't work if a non-canonical hostname was used in the devname.
446 /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
448 if (memcmp(p, "nfs@", 4) != 0)
451 if (strcmp(p, clp->cl_hostname) != 0)
457 * pg_authenticate method for nfsv4 callback threads.
459 * The authflavor has been negotiated, so an incorrect flavor is a server
460 * bug. Deny packets with incorrect authflavor.
462 * All other checking done after NFS decoding where the nfs_client can be
463 * found in nfs4_callback_compound
465 static int nfs_callback_authenticate(struct svc_rqst *rqstp)
467 switch (rqstp->rq_authop->flavour) {
469 if (rqstp->rq_proc != CB_NULL)
473 /* No RPC_AUTH_GSS support yet in NFSv4.1 */
474 if (svc_is_backchannel(rqstp))
481 * Define NFS4 callback program
483 static struct svc_version *nfs4_callback_version[] = {
484 [1] = &nfs4_callback_version1,
485 [4] = &nfs4_callback_version4,
488 static struct svc_stat nfs4_callback_stats;
490 static struct svc_program nfs4_callback_program = {
491 .pg_prog = NFS4_CALLBACK, /* RPC service number */
492 .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
493 .pg_vers = nfs4_callback_version, /* version table */
494 .pg_name = "NFSv4 callback", /* service name */
495 .pg_class = "nfs", /* authentication class */
496 .pg_stats = &nfs4_callback_stats,
497 .pg_authenticate = nfs_callback_authenticate,