blob: 75f309c8741a066ff8c7b8443452a4b8d98b8740 [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>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020017
18#include <net/inet_sock.h>
19
Trond Myklebust4ce79712005-06-22 17:16:21 +000020#include "nfs4_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include "callback.h"
David Howells24c8dbb2006-08-22 20:06:10 -040022#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
24#define NFSDBG_FACILITY NFSDBG_CALLBACK
25
26struct nfs_callback_data {
27 unsigned int users;
28 struct svc_serv *serv;
29 pid_t pid;
30 struct completion started;
31 struct completion stopped;
32};
33
34static struct nfs_callback_data nfs_callback_info;
Ingo Molnar353ab6e2006-03-26 01:37:12 -080035static DEFINE_MUTEX(nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070036static struct svc_program nfs4_callback_program;
37
Trond Myklebusta72b4422006-01-03 09:55:41 +010038unsigned int nfs_callback_set_tcpport;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039unsigned short nfs_callback_tcpport;
David Howells7d4e2742006-08-22 20:06:07 -040040static const int nfs_set_port_min = 0;
41static const int nfs_set_port_max = 65535;
42
43static int param_set_port(const char *val, struct kernel_param *kp)
44{
45 char *endp;
46 int num = simple_strtol(val, &endp, 0);
47 if (endp == val || *endp || num < nfs_set_port_min || num > nfs_set_port_max)
48 return -EINVAL;
49 *((int *)kp->arg) = num;
50 return 0;
51}
52
53module_param_call(callback_tcpport, param_set_port, param_get_int,
54 &nfs_callback_set_tcpport, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
56/*
57 * This is the callback kernel thread.
58 */
59static void nfs_callback_svc(struct svc_rqst *rqstp)
60{
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 int err;
62
63 __module_get(THIS_MODULE);
64 lock_kernel();
65
66 nfs_callback_info.pid = current->pid;
67 daemonize("nfsv4-svc");
68 /* Process request with signals blocked, but allow SIGKILL. */
69 allow_signal(SIGKILL);
70
71 complete(&nfs_callback_info.started);
72
Trond Myklebust1dd761e2006-03-20 13:44:49 -050073 for(;;) {
Chuck Leverad06e4b2007-02-12 00:53:32 -080074 char buf[RPC_MAX_ADDRBUFLEN];
75
Trond Myklebust1dd761e2006-03-20 13:44:49 -050076 if (signalled()) {
77 if (nfs_callback_info.users == 0)
78 break;
79 flush_signals(current);
80 }
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);
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 if (err == -EAGAIN || err == -EINTR)
86 continue;
87 if (err < 0) {
88 printk(KERN_WARNING
89 "%s: terminating on error %d\n",
90 __FUNCTION__, -err);
91 break;
92 }
Chuck Leverad06e4b2007-02-12 00:53:32 -080093 dprintk("%s: request from %s\n", __FUNCTION__,
94 svc_print_addr(rqstp, buf, sizeof(buf)));
NeilBrown6fb2b472006-10-02 02:17:50 -070095 svc_process(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 }
97
Trond Myklebustf25bc342006-03-20 13:44:46 -050098 svc_exit_thread(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 nfs_callback_info.pid = 0;
100 complete(&nfs_callback_info.stopped);
101 unlock_kernel();
102 module_put_and_exit(0);
103}
104
105/*
106 * Bring up the server process if it is not already up.
107 */
108int nfs_callback_up(void)
109{
110 struct svc_serv *serv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 int ret = 0;
112
113 lock_kernel();
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800114 mutex_lock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 if (nfs_callback_info.users++ || nfs_callback_info.pid != 0)
116 goto out;
117 init_completion(&nfs_callback_info.started);
118 init_completion(&nfs_callback_info.stopped);
NeilBrownbc591cc2006-10-02 02:17:44 -0700119 serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 ret = -ENOMEM;
121 if (!serv)
122 goto out_err;
Chuck Lever482fb942007-02-12 00:53:29 -0800123
124 ret = svc_makesock(serv, IPPROTO_TCP, nfs_callback_set_tcpport,
125 SVC_SOCK_ANONYMOUS);
126 if (ret <= 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 goto out_destroy;
Chuck Lever482fb942007-02-12 00:53:29 -0800128 nfs_callback_tcpport = ret;
129 dprintk("Callback port = 0x%x\n", nfs_callback_tcpport);
130
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 ret = svc_create_thread(nfs_callback_svc, serv);
132 if (ret < 0)
133 goto out_destroy;
134 nfs_callback_info.serv = serv;
135 wait_for_completion(&nfs_callback_info.started);
136out:
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800137 mutex_unlock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 unlock_kernel();
139 return ret;
140out_destroy:
Chuck Lever482fb942007-02-12 00:53:29 -0800141 dprintk("Couldn't create callback socket or server thread; err = %d\n",
142 ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 svc_destroy(serv);
144out_err:
145 nfs_callback_info.users--;
146 goto out;
147}
148
149/*
150 * Kill the server process if it is not already up.
151 */
David Howells5ae1fbc2006-08-22 20:06:08 -0400152void nfs_callback_down(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 lock_kernel();
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800155 mutex_lock(&nfs_callback_mutex);
Trond Myklebust1dd761e2006-03-20 13:44:49 -0500156 nfs_callback_info.users--;
157 do {
158 if (nfs_callback_info.users != 0 || nfs_callback_info.pid == 0)
159 break;
160 if (kill_proc(nfs_callback_info.pid, SIGKILL, 1) < 0)
161 break;
162 } while (wait_for_completion_timeout(&nfs_callback_info.stopped, 5*HZ) == 0);
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800163 mutex_unlock(&nfs_callback_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 unlock_kernel();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165}
166
167static int nfs_callback_authenticate(struct svc_rqst *rqstp)
168{
Chuck Lever27459f02007-02-12 00:53:34 -0800169 struct sockaddr_in *addr = svc_addr_in(rqstp);
David Howellsadfa6f92006-08-22 20:06:08 -0400170 struct nfs_client *clp;
Chuck Leverad06e4b2007-02-12 00:53:32 -0800171 char buf[RPC_MAX_ADDRBUFLEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
173 /* Don't talk to strangers */
David Howells24c8dbb2006-08-22 20:06:10 -0400174 clp = nfs_find_client(addr, 4);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 if (clp == NULL)
176 return SVC_DROP;
Chuck Leverad06e4b2007-02-12 00:53:32 -0800177
178 dprintk("%s: %s NFSv4 callback!\n", __FUNCTION__,
179 svc_print_addr(rqstp, buf, sizeof(buf)));
David Howells24c8dbb2006-08-22 20:06:10 -0400180 nfs_put_client(clp);
Chuck Leverad06e4b2007-02-12 00:53:32 -0800181
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 switch (rqstp->rq_authop->flavour) {
183 case RPC_AUTH_NULL:
184 if (rqstp->rq_proc != CB_NULL)
185 return SVC_DENIED;
186 break;
187 case RPC_AUTH_UNIX:
188 break;
189 case RPC_AUTH_GSS:
190 /* FIXME: RPCSEC_GSS handling? */
191 default:
192 return SVC_DENIED;
193 }
194 return SVC_OK;
195}
196
197/*
198 * Define NFS4 callback program
199 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200static struct svc_version *nfs4_callback_version[] = {
201 [1] = &nfs4_callback_version1,
202};
203
204static struct svc_stat nfs4_callback_stats;
205
206static struct svc_program nfs4_callback_program = {
207 .pg_prog = NFS4_CALLBACK, /* RPC service number */
208 .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
209 .pg_vers = nfs4_callback_version, /* version table */
210 .pg_name = "NFSv4 callback", /* service name */
211 .pg_class = "nfs", /* authentication class */
212 .pg_stats = &nfs4_callback_stats,
213 .pg_authenticate = nfs_callback_authenticate,
214};