blob: e3d29426905848101510bf0fea21f4fa2378794a [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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/sunrpc/svc.h>
13#include <linux/sunrpc/svcsock.h>
14#include <linux/nfs_fs.h>
Ingo Molnar353ab6e2006-03-26 01:37:12 -080015#include <linux/mutex.h>
Rafael J. Wysocki83144182007-07-17 04:03:35 -070016#include <linux/freezer.h>
Jeff Laytona277e332008-02-20 08:55:30 -050017#include <linux/kthread.h>
Olga Kornievskaia945b34a2008-12-23 16:18:34 -050018#include <linux/sunrpc/svcauth_gss.h>
Ricardo Labiagaa43cde92009-04-01 09:23:08 -040019#include <linux/sunrpc/bc_xprt.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020020
21#include <net/inet_sock.h>
22
Trond Myklebust4ce79712005-06-22 17:16:21 +000023#include "nfs4_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include "callback.h"
David Howells24c8dbb2006-08-22 20:06:10 -040025#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070026
27#define NFSDBG_FACILITY NFSDBG_CALLBACK
28
29struct nfs_callback_data {
30 unsigned int users;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -040031 struct svc_serv *serv;
Jeff Layton5afc5972008-06-11 10:03:11 -040032 struct svc_rqst *rqst;
Jeff Laytona277e332008-02-20 08:55:30 -050033 struct task_struct *task;
Linus Torvalds1da177e2005-04-16 15:20:36 -070034};
35
Andy Adamsone82dc222009-04-01 09:23:14 -040036static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
Ingo Molnar353ab6e2006-03-26 01:37:12 -080037static DEFINE_MUTEX(nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070038static struct svc_program nfs4_callback_program;
39
Trond Myklebusta72b4422006-01-03 09:55:41 +010040unsigned int nfs_callback_set_tcpport;
Linus Torvalds1da177e2005-04-16 15:20:36 -070041unsigned short nfs_callback_tcpport;
Chuck Leverf738f512009-03-18 20:48:06 -040042unsigned short nfs_callback_tcpport6;
Trond Myklebustc140aa92009-08-09 15:06:19 -040043#define NFS_CALLBACK_MAXPORTNR (65535U)
David Howells7d4e2742006-08-22 20:06:07 -040044
Rusty Russell9bbb9e52010-08-11 23:04:12 -060045static int param_set_portnr(const char *val, const struct kernel_param *kp)
David Howells7d4e2742006-08-22 20:06:07 -040046{
Trond Myklebustc140aa92009-08-09 15:06:19 -040047 unsigned long num;
48 int ret;
49
50 if (!val)
David Howells7d4e2742006-08-22 20:06:07 -040051 return -EINVAL;
Trond Myklebustc140aa92009-08-09 15:06:19 -040052 ret = strict_strtoul(val, 0, &num);
53 if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
54 return -EINVAL;
55 *((unsigned int *)kp->arg) = num;
David Howells7d4e2742006-08-22 20:06:07 -040056 return 0;
57}
Rusty Russell9bbb9e52010-08-11 23:04:12 -060058static struct kernel_param_ops param_ops_portnr = {
59 .set = param_set_portnr,
60 .get = param_get_uint,
61};
Trond Myklebustc140aa92009-08-09 15:06:19 -040062#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
63
64module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
66/*
Andy Adamsone82dc222009-04-01 09:23:14 -040067 * This is the NFSv4 callback kernel thread.
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 */
Jeff Laytona277e332008-02-20 08:55:30 -050069static int
Benny Halevy71468512009-04-01 09:22:56 -040070nfs4_callback_svc(void *vrqstp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071{
Jeff Layton06e02d62008-04-08 15:40:07 -040072 int err, preverr = 0;
Jeff Laytona277e332008-02-20 08:55:30 -050073 struct svc_rqst *rqstp = vrqstp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
Rafael J. Wysocki83144182007-07-17 04:03:35 -070075 set_freezable();
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
Jeff Laytona277e332008-02-20 08:55:30 -050077 while (!kthread_should_stop()) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 /*
79 * Listen for a request on the socket
80 */
NeilBrown6fb2b472006-10-02 02:17:50 -070081 err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT);
Jeff Layton06e02d62008-04-08 15:40:07 -040082 if (err == -EAGAIN || err == -EINTR) {
83 preverr = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 }
Jeff Layton06e02d62008-04-08 15:40:07 -040086 if (err < 0) {
87 if (err != preverr) {
88 printk(KERN_WARNING "%s: unexpected error "
89 "from svc_recv (%d)\n", __func__, err);
90 preverr = err;
91 }
92 schedule_timeout_uninterruptible(HZ);
93 continue;
94 }
95 preverr = err;
NeilBrown6fb2b472006-10-02 02:17:50 -070096 svc_process(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 }
Jeff Laytona277e332008-02-20 08:55:30 -050098 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070099}
100
101/*
Benny Halevy71468512009-04-01 09:22:56 -0400102 * Prepare to bring up the NFSv4 callback service
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 */
Benny Halevy71468512009-04-01 09:22:56 -0400104struct svc_rqst *
105nfs4_callback_up(struct svc_serv *serv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106{
Benny Halevy71468512009-04-01 09:22:56 -0400107 int ret;
Chuck Lever482fb942007-02-12 00:53:29 -0800108
Pavel Emelyanovfc5d00b2010-09-29 16:03:50 +0400109 ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET,
Chuck Lever9652ada2009-03-18 20:46:21 -0400110 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
Chuck Lever482fb942007-02-12 00:53:29 -0800111 if (ret <= 0)
Jeff Layton8e600292008-02-11 10:00:20 -0500112 goto out_err;
Chuck Lever482fb942007-02-12 00:53:29 -0800113 nfs_callback_tcpport = ret;
Chuck Lever18de9732008-10-16 17:41:11 -0400114 dprintk("NFS: Callback listener port = %u (af %u)\n",
Chuck Lever26298ca2009-03-18 20:46:36 -0400115 nfs_callback_tcpport, PF_INET);
Chuck Lever482fb942007-02-12 00:53:29 -0800116
Pavel Emelyanovfc5d00b2010-09-29 16:03:50 +0400117 ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET6,
Chuck Leverf738f512009-03-18 20:48:06 -0400118 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
119 if (ret > 0) {
120 nfs_callback_tcpport6 = ret;
121 dprintk("NFS: Callback listener port = %u (af %u)\n",
122 nfs_callback_tcpport6, PF_INET6);
Chuck Lever18fc3162009-06-17 18:02:10 -0700123 } else if (ret == -EAFNOSUPPORT)
124 ret = 0;
125 else
Chuck Leverf738f512009-03-18 20:48:06 -0400126 goto out_err;
Chuck Leverf738f512009-03-18 20:48:06 -0400127
Benny Halevy71468512009-04-01 09:22:56 -0400128 return svc_prepare_thread(serv, &serv->sv_pools[0]);
129
130out_err:
131 if (ret == 0)
132 ret = -ENOMEM;
133 return ERR_PTR(ret);
134}
135
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400136#if defined(CONFIG_NFS_V4_1)
137/*
138 * The callback service for NFSv4.1 callbacks
139 */
140static int
141nfs41_callback_svc(void *vrqstp)
142{
143 struct svc_rqst *rqstp = vrqstp;
144 struct svc_serv *serv = rqstp->rq_server;
145 struct rpc_rqst *req;
146 int error;
147 DEFINE_WAIT(wq);
148
149 set_freezable();
150
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400151 while (!kthread_should_stop()) {
152 prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
153 spin_lock_bh(&serv->sv_cb_lock);
154 if (!list_empty(&serv->sv_cb_list)) {
155 req = list_first_entry(&serv->sv_cb_list,
156 struct rpc_rqst, rq_bc_list);
157 list_del(&req->rq_bc_list);
158 spin_unlock_bh(&serv->sv_cb_lock);
159 dprintk("Invoking bc_svc_process()\n");
160 error = bc_svc_process(serv, req, rqstp);
161 dprintk("bc_svc_process() returned w/ error code= %d\n",
162 error);
163 } else {
164 spin_unlock_bh(&serv->sv_cb_lock);
165 schedule();
166 }
167 finish_wait(&serv->sv_cb_waitq, &wq);
168 }
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400169 return 0;
170}
171
172/*
173 * Bring up the NFSv4.1 callback service
174 */
175struct svc_rqst *
176nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
177{
Andy Adamson01c9a0b2011-01-06 02:04:28 +0000178 struct svc_rqst *rqstp;
179 int ret;
Benny Halevy8f975242009-04-01 09:23:11 -0400180
Andy Adamson01c9a0b2011-01-06 02:04:28 +0000181 /*
182 * Create an svc_sock for the back channel service that shares the
183 * fore channel connection.
184 * Returns the input port (0) and sets the svc_serv bc_xprt on success
185 */
186 ret = svc_create_xprt(serv, "tcp-bc", &init_net, PF_INET, 0,
187 SVC_SOCK_ANONYMOUS);
188 if (ret < 0) {
189 rqstp = ERR_PTR(ret);
Benny Halevy8f975242009-04-01 09:23:11 -0400190 goto out;
Andy Adamson01c9a0b2011-01-06 02:04:28 +0000191 }
Benny Halevy8f975242009-04-01 09:23:11 -0400192
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400193 /*
194 * Save the svc_serv in the transport so that it can
195 * be referenced when the session backchannel is initialized
196 */
197 xprt->bc_serv = serv;
198
199 INIT_LIST_HEAD(&serv->sv_cb_list);
200 spin_lock_init(&serv->sv_cb_lock);
201 init_waitqueue_head(&serv->sv_cb_waitq);
Benny Halevy8f975242009-04-01 09:23:11 -0400202 rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
Andy Adamson01c9a0b2011-01-06 02:04:28 +0000203 if (IS_ERR(rqstp)) {
Andy Adamson4a19de02011-01-06 02:04:35 +0000204 svc_xprt_put(serv->sv_bc_xprt);
205 serv->sv_bc_xprt = NULL;
Andy Adamson01c9a0b2011-01-06 02:04:28 +0000206 }
Benny Halevy8f975242009-04-01 09:23:11 -0400207out:
Andy Adamson01c9a0b2011-01-06 02:04:28 +0000208 dprintk("--> %s return %ld\n", __func__,
209 IS_ERR(rqstp) ? PTR_ERR(rqstp) : 0);
Benny Halevy8f975242009-04-01 09:23:11 -0400210 return rqstp;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400211}
212
213static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
214 struct svc_serv *serv, struct rpc_xprt *xprt,
215 struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
216{
217 if (minorversion) {
218 *rqstpp = nfs41_callback_up(serv, xprt);
219 *callback_svc = nfs41_callback_svc;
220 }
221 return minorversion;
222}
223
224static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
225 struct nfs_callback_data *cb_info)
226{
227 if (minorversion)
228 xprt->bc_serv = cb_info->serv;
229}
230#else
231static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
232 struct svc_serv *serv, struct rpc_xprt *xprt,
233 struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
234{
235 return 0;
236}
237
238static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
239 struct nfs_callback_data *cb_info)
240{
241}
242#endif /* CONFIG_NFS_V4_1 */
243
Benny Halevy71468512009-04-01 09:22:56 -0400244/*
245 * Bring up the callback thread if it is not already up.
246 */
247int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
248{
249 struct svc_serv *serv = NULL;
250 struct svc_rqst *rqstp;
251 int (*callback_svc)(void *vrqstp);
Andy Adamsone82dc222009-04-01 09:23:14 -0400252 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
Benny Halevy71468512009-04-01 09:22:56 -0400253 char svc_name[12];
254 int ret = 0;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400255 int minorversion_setup;
Benny Halevy71468512009-04-01 09:22:56 -0400256
257 mutex_lock(&nfs_callback_mutex);
Andy Adamsone82dc222009-04-01 09:23:14 -0400258 if (cb_info->users++ || cb_info->task != NULL) {
259 nfs_callback_bc_serv(minorversion, xprt, cb_info);
Benny Halevy71468512009-04-01 09:22:56 -0400260 goto out;
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400261 }
Benny Halevy71468512009-04-01 09:22:56 -0400262 serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
263 if (!serv) {
264 ret = -ENOMEM;
265 goto out_err;
266 }
267
Ricardo Labiagaa43cde92009-04-01 09:23:08 -0400268 minorversion_setup = nfs_minorversion_callback_svc_setup(minorversion,
269 serv, xprt, &rqstp, &callback_svc);
270 if (!minorversion_setup) {
271 /* v4.0 callback setup */
Benny Halevy71468512009-04-01 09:22:56 -0400272 rqstp = nfs4_callback_up(serv);
273 callback_svc = nfs4_callback_svc;
Benny Halevy71468512009-04-01 09:22:56 -0400274 }
275
276 if (IS_ERR(rqstp)) {
277 ret = PTR_ERR(rqstp);
Jeff Layton8e600292008-02-11 10:00:20 -0500278 goto out_err;
Jeff Laytona277e332008-02-20 08:55:30 -0500279 }
280
281 svc_sock_update_bufs(serv);
Jeff Laytona277e332008-02-20 08:55:30 -0500282
Benny Halevy71468512009-04-01 09:22:56 -0400283 sprintf(svc_name, "nfsv4.%u-svc", minorversion);
Andy Adamsone82dc222009-04-01 09:23:14 -0400284 cb_info->serv = serv;
285 cb_info->rqst = rqstp;
286 cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name);
287 if (IS_ERR(cb_info->task)) {
288 ret = PTR_ERR(cb_info->task);
289 svc_exit_thread(cb_info->rqst);
290 cb_info->rqst = NULL;
291 cb_info->task = NULL;
Jeff Laytona277e332008-02-20 08:55:30 -0500292 goto out_err;
293 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294out:
Jeff Layton8e600292008-02-11 10:00:20 -0500295 /*
296 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
Jeff Laytona277e332008-02-20 08:55:30 -0500297 * svc_prepare_thread increments that. So we need to call svc_destroy
Jeff Layton8e600292008-02-11 10:00:20 -0500298 * on both success and failure so that the refcount is 1 when the
299 * thread exits.
300 */
301 if (serv)
302 svc_destroy(serv);
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800303 mutex_unlock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 return ret;
Jeff Layton8e600292008-02-11 10:00:20 -0500305out_err:
Chuck Lever18de9732008-10-16 17:41:11 -0400306 dprintk("NFS: Couldn't create callback socket or server thread; "
307 "err = %d\n", ret);
Andy Adamsone82dc222009-04-01 09:23:14 -0400308 cb_info->users--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 goto out;
310}
311
312/*
Jeff Layton5afc5972008-06-11 10:03:11 -0400313 * Kill the callback thread if it's no longer being used.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 */
Andy Adamsone82dc222009-04-01 09:23:14 -0400315void nfs_callback_down(int minorversion)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316{
Andy Adamsone82dc222009-04-01 09:23:14 -0400317 struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
318
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800319 mutex_lock(&nfs_callback_mutex);
Andy Adamsone82dc222009-04-01 09:23:14 -0400320 cb_info->users--;
321 if (cb_info->users == 0 && cb_info->task != NULL) {
322 kthread_stop(cb_info->task);
323 svc_exit_thread(cb_info->rqst);
324 cb_info->serv = NULL;
325 cb_info->rqst = NULL;
326 cb_info->task = NULL;
Jeff Layton5afc5972008-06-11 10:03:11 -0400327 }
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800328 mutex_unlock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329}
330
Andy Adamson778be232011-01-25 15:38:01 +0000331/* Boolean check of RPC_AUTH_GSS principal */
332int
333check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp)
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500334{
335 struct rpc_clnt *r = clp->cl_rpcclient;
336 char *p = svc_gss_principal(rqstp);
337
Andy Adamson778be232011-01-25 15:38:01 +0000338 if (rqstp->rq_authop->flavour != RPC_AUTH_GSS)
339 return 1;
340
Andy Adamsonece0de62011-01-06 02:04:33 +0000341 /* No RPC_AUTH_GSS on NFSv4.1 back channel yet */
342 if (clp->cl_minorversion != 0)
Andy Adamson778be232011-01-25 15:38:01 +0000343 return 0;
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500344 /*
345 * It might just be a normal user principal, in which case
346 * userspace won't bother to tell us the name at all.
347 */
348 if (p == NULL)
Andy Adamson778be232011-01-25 15:38:01 +0000349 return 0;
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500350
351 /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
352
353 if (memcmp(p, "nfs@", 4) != 0)
Andy Adamson778be232011-01-25 15:38:01 +0000354 return 0;
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500355 p += 4;
356 if (strcmp(p, r->cl_server) != 0)
Andy Adamson778be232011-01-25 15:38:01 +0000357 return 0;
358 return 1;
Olga Kornievskaia945b34a2008-12-23 16:18:34 -0500359}
360
Andy Adamson778be232011-01-25 15:38:01 +0000361/*
362 * pg_authenticate method for nfsv4 callback threads.
363 *
364 * The authflavor has been negotiated, so an incorrect flavor is a server
365 * bug. Drop packets with incorrect authflavor.
366 *
367 * All other checking done after NFS decoding where the nfs_client can be
368 * found in nfs4_callback_compound
369 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370static int nfs_callback_authenticate(struct svc_rqst *rqstp)
371{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 switch (rqstp->rq_authop->flavour) {
Andy Adamson778be232011-01-25 15:38:01 +0000373 case RPC_AUTH_NULL:
374 if (rqstp->rq_proc != CB_NULL)
375 return SVC_DROP;
376 break;
377 case RPC_AUTH_GSS:
378 /* No RPC_AUTH_GSS support yet in NFSv4.1 */
379 if (svc_is_backchannel(rqstp))
380 return SVC_DROP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 }
Andy Adamson778be232011-01-25 15:38:01 +0000382 return SVC_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383}
384
385/*
386 * Define NFS4 callback program
387 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388static struct svc_version *nfs4_callback_version[] = {
389 [1] = &nfs4_callback_version1,
Alexandros Batsakis07bccc22009-12-05 13:19:01 -0500390 [4] = &nfs4_callback_version4,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391};
392
393static struct svc_stat nfs4_callback_stats;
394
395static struct svc_program nfs4_callback_program = {
396 .pg_prog = NFS4_CALLBACK, /* RPC service number */
397 .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
398 .pg_vers = nfs4_callback_version, /* version table */
399 .pg_name = "NFSv4 callback", /* service name */
400 .pg_class = "nfs", /* authentication class */
401 .pg_stats = &nfs4_callback_stats,
402 .pg_authenticate = nfs_callback_authenticate,
403};