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
|
/*
* Security plug functions
*
* Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
* Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/security.h>
#define SECURITY_FRAMEWORK_VERSION "1.0.0"
/* things that live in dummy.c */
extern struct security_operations dummy_security_ops;
extern void security_fixup_ops(struct security_operations *ops);
struct security_operations *security_ops; /* Initialized to NULL */
static inline int verify(struct security_operations *ops)
{
/* verify the security_operations structure exists */
if (!ops)
return -EINVAL;
security_fixup_ops(ops);
return 0;
}
static void __init do_security_initcalls(void)
{
initcall_t *call;
call = __security_initcall_start;
while (call < __security_initcall_end) {
(*call) ();
call++;
}
}
/**
* security_init - initializes the security framework
*
* This should be called early in the kernel initialization sequence.
*/
int __init security_init(void)
{
printk(KERN_INFO "Security Framework v" SECURITY_FRAMEWORK_VERSION
" initialized\n");
if (verify(&dummy_security_ops)) {
printk(KERN_ERR "%s could not verify "
"dummy_security_ops structure.\n", __FUNCTION__);
return -EIO;
}
security_ops = &dummy_security_ops;
do_security_initcalls();
return 0;
}
/**
* register_security - registers a security framework with the kernel
* @ops: a pointer to the struct security_options that is to be registered
*
* This function is to allow a security module to register itself with the
* kernel security subsystem. Some rudimentary checking is done on the @ops
* value passed to this function. A call to unregister_security() should be
* done to remove this security_options structure from the kernel.
*
* If there is already a security module registered with the kernel,
* an error will be returned. Otherwise 0 is returned on success.
*/
int register_security(struct security_operations *ops)
{
if (verify(ops)) {
printk(KERN_DEBUG "%s could not verify "
"security_operations structure.\n", __FUNCTION__);
return -EINVAL;
}
if (security_ops != &dummy_security_ops)
return -EAGAIN;
security_ops = ops;
return 0;
}
/**
* unregister_security - unregisters a security framework with the kernel
* @ops: a pointer to the struct security_options that is to be registered
*
* This function removes a struct security_operations variable that had
* previously been registered with a successful call to register_security().
*
* If @ops does not match the valued previously passed to register_security()
* an error is returned. Otherwise the default security options is set to the
* the dummy_security_ops structure, and 0 is returned.
*/
int unregister_security(struct security_operations *ops)
{
if (ops != security_ops) {
printk(KERN_INFO "%s: trying to unregister "
"a security_opts structure that is not "
"registered, failing.\n", __FUNCTION__);
return -EINVAL;
}
security_ops = &dummy_security_ops;
return 0;
}
/**
* mod_reg_security - allows security modules to be "stacked"
* @name: a pointer to a string with the name of the security_options to be registered
* @ops: a pointer to the struct security_options that is to be registered
*
* This function allows security modules to be stacked if the currently loaded
* security module allows this to happen. It passes the @name and @ops to the
* register_security function of the currently loaded security module.
*
* The return value depends on the currently loaded security module, with 0 as
* success.
*/
int mod_reg_security(const char *name, struct security_operations *ops)
{
if (verify(ops)) {
printk(KERN_INFO "%s could not verify "
"security operations.\n", __FUNCTION__);
return -EINVAL;
}
if (ops == security_ops) {
printk(KERN_INFO "%s security operations "
"already registered.\n", __FUNCTION__);
return -EINVAL;
}
return security_ops->register_security(name, ops);
}
/**
* mod_unreg_security - allows a security module registered with mod_reg_security() to be unloaded
* @name: a pointer to a string with the name of the security_options to be removed
* @ops: a pointer to the struct security_options that is to be removed
*
* This function allows security modules that have been successfully registered
* with a call to mod_reg_security() to be unloaded from the system.
* This calls the currently loaded security module's unregister_security() call
* with the @name and @ops variables.
*
* The return value depends on the currently loaded security module, with 0 as
* success.
*/
int mod_unreg_security(const char *name, struct security_operations *ops)
{
if (ops == security_ops) {
printk(KERN_INFO "%s invalid attempt to unregister "
" primary security ops.\n", __FUNCTION__);
return -EINVAL;
}
return security_ops->unregister_security(name, ops);
}
EXPORT_SYMBOL_GPL(register_security);
EXPORT_SYMBOL_GPL(unregister_security);
EXPORT_SYMBOL_GPL(mod_reg_security);
EXPORT_SYMBOL_GPL(mod_unreg_security);
EXPORT_SYMBOL(security_ops);
|
