1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/*
* linux/fs/nfs/callback.c
*
* Copyright (C) 2004 Trond Myklebust
*
* NFSv4 callback handling
*/
#include <linux/completion.h>
#include <linux/ip.h>
#include <linux/module.h>
#include <linux/smp_lock.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/nfs_fs.h>
#include <linux/mutex.h>
#include <linux/freezer.h>
#include <linux/kthread.h>
#include <net/inet_sock.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "internal.h"
#define NFSDBG_FACILITY NFSDBG_CALLBACK
struct nfs_callback_data {
unsigned int users;
struct svc_serv *serv;
struct task_struct *task;
};
static struct nfs_callback_data nfs_callback_info;
static DEFINE_MUTEX(nfs_callback_mutex);
static struct svc_program nfs4_callback_program;
unsigned int nfs_callback_set_tcpport;
unsigned short nfs_callback_tcpport;
static const int nfs_set_port_min = 0;
static const int nfs_set_port_max = 65535;
static int param_set_port(const char *val, struct kernel_param *kp)
{
char *endp;
int num = simple_strtol(val, &endp, 0);
if (endp == val || *endp || num < nfs_set_port_min || num > nfs_set_port_max)
return -EINVAL;
*((int *)kp->arg) = num;
return 0;
}
module_param_call(callback_tcpport, param_set_port, param_get_int,
&nfs_callback_set_tcpport, 0644);
/*
* This is the callback kernel thread.
*/
static int
nfs_callback_svc(void *vrqstp)
{
int err;
struct svc_rqst *rqstp = vrqstp;
set_freezable();
/*
* FIXME: do we really need to run this under the BKL? If so, please
* add a comment about what it's intended to protect.
*/
lock_kernel();
while (!kthread_should_stop()) {
/*
* Listen for a request on the socket
*/
err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT);
if (err == -EAGAIN || err == -EINTR)
continue;
if (err < 0) {
printk(KERN_WARNING
"%s: terminating on error %d\n",
__FUNCTION__, -err);
break;
}
svc_process(rqstp);
}
unlock_kernel();
nfs_callback_info.task = NULL;
svc_exit_thread(rqstp);
return 0;
}
/*
* Bring up the server process if it is not already up.
*/
int nfs_callback_up(void)
{
struct svc_serv *serv = NULL;
struct svc_rqst *rqstp;
int ret = 0;
lock_kernel();
mutex_lock(&nfs_callback_mutex);
if (nfs_callback_info.users++ || nfs_callback_info.task != NULL)
goto out;
serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
ret = -ENOMEM;
if (!serv)
goto out_err;
ret = svc_create_xprt(serv, "tcp", nfs_callback_set_tcpport,
SVC_SOCK_ANONYMOUS);
if (ret <= 0)
goto out_err;
nfs_callback_tcpport = ret;
dprintk("Callback port = 0x%x\n", nfs_callback_tcpport);
rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
if (IS_ERR(rqstp)) {
ret = PTR_ERR(rqstp);
goto out_err;
}
svc_sock_update_bufs(serv);
nfs_callback_info.serv = serv;
nfs_callback_info.task = kthread_run(nfs_callback_svc, rqstp,
"nfsv4-svc");
if (IS_ERR(nfs_callback_info.task)) {
ret = PTR_ERR(nfs_callback_info.task);
nfs_callback_info.serv = NULL;
nfs_callback_info.task = NULL;
svc_exit_thread(rqstp);
goto out_err;
}
out:
/*
* svc_create creates the svc_serv with sv_nrthreads == 1, and then
* svc_prepare_thread increments that. So we need to call svc_destroy
* on both success and failure so that the refcount is 1 when the
* thread exits.
*/
if (serv)
svc_destroy(serv);
mutex_unlock(&nfs_callback_mutex);
unlock_kernel();
return ret;
out_err:
dprintk("Couldn't create callback socket or server thread; err = %d\n",
ret);
nfs_callback_info.users--;
goto out;
}
/*
* Kill the server process if it is not already up.
*/
void nfs_callback_down(void)
{
lock_kernel();
mutex_lock(&nfs_callback_mutex);
nfs_callback_info.users--;
if (nfs_callback_info.users == 0 && nfs_callback_info.task != NULL)
kthread_stop(nfs_callback_info.task);
mutex_unlock(&nfs_callback_mutex);
unlock_kernel();
}
static int nfs_callback_authenticate(struct svc_rqst *rqstp)
{
struct nfs_client *clp;
RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
/* Don't talk to strangers */
clp = nfs_find_client(svc_addr(rqstp), 4);
if (clp == NULL)
return SVC_DROP;
dprintk("%s: %s NFSv4 callback!\n", __FUNCTION__,
svc_print_addr(rqstp, buf, sizeof(buf)));
nfs_put_client(clp);
switch (rqstp->rq_authop->flavour) {
case RPC_AUTH_NULL:
if (rqstp->rq_proc != CB_NULL)
return SVC_DENIED;
break;
case RPC_AUTH_UNIX:
break;
case RPC_AUTH_GSS:
/* FIXME: RPCSEC_GSS handling? */
default:
return SVC_DENIED;
}
return SVC_OK;
}
/*
* Define NFS4 callback program
*/
static struct svc_version *nfs4_callback_version[] = {
[1] = &nfs4_callback_version1,
};
static struct svc_stat nfs4_callback_stats;
static struct svc_program nfs4_callback_program = {
.pg_prog = NFS4_CALLBACK, /* RPC service number */
.pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */
.pg_vers = nfs4_callback_version, /* version table */
.pg_name = "NFSv4 callback", /* service name */
.pg_class = "nfs", /* authentication class */
.pg_stats = &nfs4_callback_stats,
.pg_authenticate = nfs_callback_authenticate,
};
|
