blob: e17b49e2eabd8dcb887819bbf2d8c714e4e2085f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/nfs/callback.c
3 *
4 * Copyright (C) 2004 Trond Myklebust
5 *
6 * NFSv4 callback handling
7 */
8
Linus Torvalds1da177e2005-04-16 15:20:36 -07009#include <linux/completion.h>
10#include <linux/ip.h>
11#include <linux/module.h>
12#include <linux/smp_lock.h>
13#include <linux/sunrpc/svc.h>
14#include <linux/sunrpc/svcsock.h>
15#include <linux/nfs_fs.h>
Ingo Molnar353ab6e2006-03-26 01:37:12 -080016#include <linux/mutex.h>
Rafael J. Wysocki83144182007-07-17 04:03:35 -070017#include <linux/freezer.h>
Jeff Laytona277e332008-02-20 08:55:30 -050018#include <linux/kthread.h>
Olga Kornievskaia945b34a2008-12-23 16:18:34 -050019#include <linux/sunrpc/svcauth_gss.h>
Ricardo Labiagaa43cde92009-04-01 09:23:08 -040020#if defined(CONFIG_NFS_V4_1)
21#include <linux/sunrpc/bc_xprt.h>
22#endif
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020023
24#include <net/inet_sock.h>
25
Trond Myklebust4ce79712005-06-22 17:16:21 +000026#include "nfs4_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include "callback.h"
David Howells24c8dbb2006-08-22 20:06:10 -040028#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
30#define NFSDBG_FACILITY NFSDBG_CALLBACK
31
32struct nfs_callback_data {
33 unsigned int users;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -040034 struct svc_serv *serv;
Jeff Layton5afc5972008-06-11 10:03:11 -040035 struct svc_rqst *rqst;
Jeff Laytona277e332008-02-20 08:55:30 -050036 struct task_struct *task;
Linus Torvalds1da177e2005-04-16 15:20:36 -070037};
38
Andy Adamsone82dc222009-04-01 09:23:14 -040039static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
Ingo Molnar353ab6e2006-03-26 01:37:12 -080040static DEFINE_MUTEX(nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070041static struct svc_program nfs4_callback_program;
42
Trond Myklebusta72b4422006-01-03 09:55:41 +010043unsigned int nfs_callback_set_tcpport;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044unsigned short nfs_callback_tcpport;
Chuck Leverf738f512009-03-18 20:48:06 -040045unsigned short nfs_callback_tcpport6;
Trond Myklebustc140aa92009-08-09 15:06:19 -040046#define NFS_CALLBACK_MAXPORTNR (65535U)
David Howells7d4e2742006-08-22 20:06:07 -040047
Rusty Russell9bbb9e52010-08-11 23:04:12 -060048static int param_set_portnr(const char *val, const struct kernel_param *kp)
David Howells7d4e2742006-08-22 20:06:07 -040049{
Trond Myklebustc140aa92009-08-09 15:06:19 -040050 unsigned long num;
51 int ret;
52
53 if (!val)
David Howells7d4e2742006-08-22 20:06:07 -040054 return -EINVAL;
Trond Myklebustc140aa92009-08-09 15:06:19 -040055 ret = strict_strtoul(val, 0, &num);
56 if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
57 return -EINVAL;
58 *((unsigned int *)kp->arg) = num;
David Howells7d4e2742006-08-22 20:06:07 -040059 return 0;
60}
Rusty Russell9bbb9e52010-08-11 23:04:12 -060061static struct kernel_param_ops param_ops_portnr = {
62 .set = param_set_portnr,
63 .get = param_get_uint,
64};
Trond Myklebustc140aa92009-08-09 15:06:19 -040065#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
66
67module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69/*
Andy Adamsone82dc222009-04-01 09:23:14 -040070 * This is the NFSv4 callback kernel thread.
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 */
Jeff Laytona277e332008-02-20 08:55:30 -050072static int
Benny Halevy71468512009-04-01 09:22:56 -040073nfs4_callback_svc(void *vrqstp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070074{
Jeff Layton06e02d62008-04-08 15:40:07 -040075 int err, preverr = 0;
Jeff Laytona277e332008-02-20 08:55:30 -050076 struct svc_rqst *rqstp = vrqstp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
Rafael J. Wysocki83144182007-07-17 04:03:35 -070078 set_freezable();
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Jeff Laytona277e332008-02-20 08:55:30 -050080 while (!kthread_should_stop()) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 /*
82 * Listen for a request on the socket
83 */
NeilBrown6fb2b472006-10-02 02:17:50 -070084 err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT);
Jeff Layton06e02d62008-04-08 15:40:07 -040085 if (err == -EAGAIN || err == -EINTR) {
86 preverr = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 }
Jeff Layton06e02d62008-04-08 15:40:07 -040089 if (err < 0) {
90 if (err != preverr) {
91 printk(KERN_WARNING "%s: unexpected error "
92 "from svc_recv (%d)\n", __func__, err);
93 preverr = err;
94 }
95 schedule_timeout_uninterruptible(HZ);
96 continue;
97 }
98 preverr = err;
NeilBrown6fb2b472006-10-02 02:17:50 -070099 svc_process(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 }
Jeff Laytona277e332008-02-20 08:55:30 -0500101 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102}
103
104/*
Benny Halevy71468512009-04-01 09:22:56 -0400105 * Prepare to bring up the NFSv4 callback service
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 */
Benny Halevy71468512009-04-01 09:22:56 -0400107struct svc_rqst *
108nfs4_callback_up(struct svc_serv *serv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109{
Benny Halevy71468512009-04-01 09:22:56 -0400110 int ret;
Chuck Lever482fb942007-02-12 00:53:29 -0800111
Chuck Lever26298ca2009-03-18 20:46:36 -0400112 ret = svc_create_xprt(serv, "tcp", PF_INET,
Chuck Lever9652ada2009-03-18 20:46:21 -0400113 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
Chuck Lever482fb942007-02-12 00:53:29 -0800114 if (ret <= 0)
Jeff Layton8e600292008-02-11 10:00:20 -0500115 goto out_err;
Chuck Lever482fb942007-02-12 00:53:29 -0800116 nfs_callback_tcpport = ret;
Chuck Lever18de9732008-10-16 17:41:11 -0400117 dprintk("NFS: Callback listener port = %u (af %u)\n",
Chuck Lever26298ca2009-03-18 20:46:36 -0400118 nfs_callback_tcpport, PF_INET);
Chuck Lever482fb942007-02-12 00:53:29 -0800119
Chuck Leverf738f512009-03-18 20:48:06 -0400120 ret = svc_create_xprt(serv, "tcp", PF_INET6,
121 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
122 if (ret > 0) {
123 nfs_callback_tcpport6 = ret;
124 dprintk("NFS: Callback listener port = %u (af %u)\n",
125 nfs_callback_tcpport6, PF_INET6);
Chuck Lever18fc3162009-06-17 18:02:10 -0700126 } else if (ret == -EAFNOSUPPORT)
127 ret = 0;
128 else
Chuck Leverf738f512009-03-18 20:48:06 -0400129 goto out_err;
Chuck Leverf738f512009-03-18 20:48:06 -0400130
Benny Halevy71468512009-04-01 09:22:56 -0400131 return svc_prepare_thread(serv, &serv->sv_pools[0]);
132
133out_err:
134 if (ret == 0)
135 ret = -ENOMEM;
136 return ERR_PTR(ret);
137}
138
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400139#if defined(CONFIG_NFS_V4_1)
140/*
141 * The callback service for NFSv4.1 callbacks
142 */
143static int
144nfs41_callback_svc(void *vrqstp)
145{
146 struct svc_rqst *rqstp = vrqstp;
147 struct svc_serv *serv = rqstp->rq_server;
148 struct rpc_rqst *req;
149 int error;
150 DEFINE_WAIT(wq);
151
152 set_freezable();
153
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400154 while (!kthread_should_stop()) {
155 prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
156 spin_lock_bh(&serv->sv_cb_lock);
157 if (!list_empty(&serv->sv_cb_list)) {
158 req = list_first_entry(&serv->sv_cb_list,
159 struct rpc_rqst, rq_bc_list);
160 list_del(&req->rq_bc_list);
161 spin_unlock_bh(&serv->sv_cb_lock);
162 dprintk("Invoking bc_svc_process()\n");
163 error = bc_svc_process(serv, req, rqstp);
164 dprintk("bc_svc_process() returned w/ error code= %d\n",
165 error);
166 } else {
167 spin_unlock_bh(&serv->sv_cb_lock);
168 schedule();
169 }
170 finish_wait(&serv->sv_cb_waitq, &wq);
171 }
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400172 return 0;
173}
174
175/*
176 * Bring up the NFSv4.1 callback service
177 */
178struct svc_rqst *
179nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
180{
Benny Halevy8f975242009-04-01 09:23:11 -0400181 struct svc_xprt *bc_xprt;
182 struct svc_rqst *rqstp = ERR_PTR(-ENOMEM);
183
184 dprintk("--> %s\n", __func__);
185 /* Create a svc_sock for the service */
186 bc_xprt = svc_sock_create(serv, xprt->prot);
187 if (!bc_xprt)
188 goto out;
189
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400190 /*
191 * Save the svc_serv in the transport so that it can
192 * be referenced when the session backchannel is initialized
193 */
Benny Halevy8f975242009-04-01 09:23:11 -0400194 serv->bc_xprt = bc_xprt;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400195 xprt->bc_serv = serv;
196
197 INIT_LIST_HEAD(&serv->sv_cb_list);
198 spin_lock_init(&serv->sv_cb_lock);
199 init_waitqueue_head(&serv->sv_cb_waitq);
Benny Halevy8f975242009-04-01 09:23:11 -0400200 rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
201 if (IS_ERR(rqstp))
202 svc_sock_destroy(bc_xprt);
203out:
204 dprintk("--> %s return %p\n", __func__, rqstp);
205 return rqstp;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400206}
207
208static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
209 struct svc_serv *serv, struct rpc_xprt *xprt,
210 struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
211{
212 if (minorversion) {
213 *rqstpp = nfs41_callback_up(serv, xprt);
214 *callback_svc = nfs41_callback_svc;
215 }
216 return minorversion;
217}
218
219static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
220 struct nfs_callback_data *cb_info)
221{
222 if (minorversion)
223 xprt->bc_serv = cb_info->serv;
224}
225#else
226static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
227 struct svc_serv *serv, struct rpc_xprt *xprt,
228 struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
229{
230 return 0;
231}
232
233static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
234 struct nfs_callback_data *cb_info)
235{
236}
237#endif /* CONFIG_NFS_V4_1 */
238
Benny Halevy71468512009-04-01 09:22:56 -0400239/*
240 * Bring up the callback thread if it is not already up.
241 */
242int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
243{
244 struct svc_serv *serv = NULL;
245 struct svc_rqst *rqstp;
246 int (*callback_svc)(void *vrqstp);
Andy Adamsone82dc222009-04-01 09:23:14 -0400247 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
Benny Halevy71468512009-04-01 09:22:56 -0400248 char svc_name[12];
249 int ret = 0;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400250 int minorversion_setup;
Benny Halevy71468512009-04-01 09:22:56 -0400251
252 mutex_lock(&nfs_callback_mutex);
Andy Adamsone82dc222009-04-01 09:23:14 -0400253 if (cb_info->users++ || cb_info->task != NULL) {
254 nfs_callback_bc_serv(minorversion, xprt, cb_info);
Benny Halevy71468512009-04-01 09:22:56 -0400255 goto out;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400256 }
Benny Halevy71468512009-04-01 09:22:56 -0400257 serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
258 if (!serv) {
259 ret = -ENOMEM;
260 goto out_err;
261 }
262
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400263 minorversion_setup = nfs_minorversion_callback_svc_setup(minorversion,
264 serv, xprt, &rqstp, &callback_svc);
265 if (!minorversion_setup) {
266 /* v4.0 callback setup */
Benny Halevy71468512009-04-01 09:22:56 -0400267 rqstp = nfs4_callback_up(serv);
268 callback_svc = nfs4_callback_svc;
Benny Halevy71468512009-04-01 09:22:56 -0400269 }
270
271 if (IS_ERR(rqstp)) {
272 ret = PTR_ERR(rqstp);
Jeff Layton8e600292008-02-11 10:00:20 -0500273 goto out_err;
Jeff Laytona277e332008-02-20 08:55:30 -0500274 }
275
276 svc_sock_update_bufs(serv);
Jeff Laytona277e332008-02-20 08:55:30 -0500277
Benny Halevy71468512009-04-01 09:22:56 -0400278 sprintf(svc_name, "nfsv4.%u-svc", minorversion);
Andy Adamsone82dc222009-04-01 09:23:14 -0400279 cb_info->serv = serv;
280 cb_info->rqst = rqstp;
281 cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name);
282 if (IS_ERR(cb_info->task)) {
283 ret = PTR_ERR(cb_info->task);
284 svc_exit_thread(cb_info->rqst);
285 cb_info->rqst = NULL;
286 cb_info->task = NULL;
Jeff Laytona277e332008-02-20 08:55:30 -0500287 goto out_err;
288 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289out:
Jeff Layton8e600292008-02-11 10:00:20 -0500290 /*
291 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
Jeff Laytona277e332008-02-20 08:55:30 -0500292 * svc_prepare_thread increments that. So we need to call svc_destroy
Jeff Layton8e600292008-02-11 10:00:20 -0500293 * on both success and failure so that the refcount is 1 when the
294 * thread exits.
295 */
296 if (serv)
297 svc_destroy(serv);
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800298 mutex_unlock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 return ret;
Jeff Layton8e600292008-02-11 10:00:20 -0500300out_err:
Chuck Lever18de9732008-10-16 17:41:11 -0400301 dprintk("NFS: Couldn't create callback socket or server thread; "
302 "err = %d\n", ret);
Andy Adamsone82dc222009-04-01 09:23:14 -0400303 cb_info->users--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 goto out;
305}
306
307/*
Jeff Layton5afc5972008-06-11 10:03:11 -0400308 * Kill the callback thread if it's no longer being used.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 */
Andy Adamsone82dc222009-04-01 09:23:14 -0400310void nfs_callback_down(int minorversion)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311{
Andy Adamsone82dc222009-04-01 09:23:14 -0400312 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
313
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800314 mutex_lock(&nfs_callback_mutex);
Andy Adamsone82dc222009-04-01 09:23:14 -0400315 cb_info->users--;
316 if (cb_info->users == 0 && cb_info->task != NULL) {
317 kthread_stop(cb_info->task);
318 svc_exit_thread(cb_info->rqst);
319 cb_info->serv = NULL;
320 cb_info->rqst = NULL;
321 cb_info->task = NULL;
Jeff Layton5afc5972008-06-11 10:03:11 -0400322 }
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800323 mutex_unlock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324}
325
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500326static int check_gss_callback_principal(struct nfs_client *clp,
327 struct svc_rqst *rqstp)
328{
329 struct rpc_clnt *r = clp->cl_rpcclient;
330 char *p = svc_gss_principal(rqstp);
331
332 /*
333 * It might just be a normal user principal, in which case
334 * userspace won't bother to tell us the name at all.
335 */
336 if (p == NULL)
337 return SVC_DENIED;
338
339 /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
340
341 if (memcmp(p, "nfs@", 4) != 0)
342 return SVC_DENIED;
343 p += 4;
344 if (strcmp(p, r->cl_server) != 0)
345 return SVC_DENIED;
346 return SVC_OK;
347}
348
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349static int nfs_callback_authenticate(struct svc_rqst *rqstp)
350{
David Howellsadfa6f92006-08-22 20:06:08 -0400351 struct nfs_client *clp;
Pavel Emelyanov5216a8e2008-02-21 10:57:45 +0300352 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500353 int ret = SVC_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
355 /* Don't talk to strangers */
Chuck Leverff052642007-12-10 14:58:44 -0500356 clp = nfs_find_client(svc_addr(rqstp), 4);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 if (clp == NULL)
358 return SVC_DROP;
Chuck Leverad06e4b2007-02-12 00:53:32 -0800359
Harvey Harrison3110ff82008-05-02 13:42:44 -0700360 dprintk("%s: %s NFSv4 callback!\n", __func__,
Chuck Leverad06e4b2007-02-12 00:53:32 -0800361 svc_print_addr(rqstp, buf, sizeof(buf)));
Chuck Leverad06e4b2007-02-12 00:53:32 -0800362
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 switch (rqstp->rq_authop->flavour) {
364 case RPC_AUTH_NULL:
365 if (rqstp->rq_proc != CB_NULL)
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500366 ret = SVC_DENIED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 break;
368 case RPC_AUTH_UNIX:
369 break;
370 case RPC_AUTH_GSS:
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500371 ret = check_gss_callback_principal(clp, rqstp);
372 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 default:
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500374 ret = SVC_DENIED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 }
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500376 nfs_put_client(clp);
377 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378}
379
380/*
381 * Define NFS4 callback program
382 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383static struct svc_version *nfs4_callback_version[] = {
384 [1] = &nfs4_callback_version1,
Alexandros Batsakis07bccc22009-12-05 13:19:01 -0500385 [4] = &nfs4_callback_version4,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386};
387
388static struct svc_stat nfs4_callback_stats;
389
390static struct svc_program nfs4_callback_program = {
391 .pg_prog = NFS4_CALLBACK, /* RPC service number */
392 .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
393 .pg_vers = nfs4_callback_version, /* version table */
394 .pg_name = "NFSv4 callback", /* service name */
395 .pg_class = "nfs", /* authentication class */
396 .pg_stats = &nfs4_callback_stats,
397 .pg_authenticate = nfs_callback_authenticate,
398};