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
|
/*
* AppArmor security module
*
* This file contains AppArmor lib definitions
*
* 2017 Canonical Ltd.
*
* 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, version 2 of the
* License.
*/
#ifndef __AA_LIB_H
#define __AA_LIB_H
#include <linux/slab.h>
#include <linux/fs.h>
#include "match.h"
/* Provide our own test for whether a write lock is held for asserts
* this is because on none SMP systems write_can_lock will always
* resolve to true, which is what you want for code making decisions
* based on it, but wrong for asserts checking that the lock is held
*/
#ifdef CONFIG_SMP
#define write_is_locked(X) !write_can_lock(X)
#else
#define write_is_locked(X) (1)
#endif /* CONFIG_SMP */
/*
* DEBUG remains global (no per profile flag) since it is mostly used in sysctl
* which is not related to profile accesses.
*/
#define AA_DEBUG(fmt, args...) \
do { \
if (aa_g_debug) \
pr_debug_ratelimited("AppArmor: " fmt, ##args); \
} while (0)
#define AA_ERROR(fmt, args...) \
pr_err_ratelimited("AppArmor: " fmt, ##args)
/* Flag indicating whether initialization completed */
extern int apparmor_initialized __initdata;
/* fn's in lib */
char *aa_split_fqname(char *args, char **ns_name);
const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name,
size_t *ns_len);
void aa_info_message(const char *str);
void *__aa_kvmalloc(size_t size, gfp_t flags);
static inline void *kvmalloc(size_t size)
{
return __aa_kvmalloc(size, 0);
}
static inline void *kvzalloc(size_t size)
{
return __aa_kvmalloc(size, __GFP_ZERO);
}
/* returns 0 if kref not incremented */
static inline int kref_get_not0(struct kref *kref)
{
return atomic_inc_not_zero(&kref->refcount);
}
/**
* aa_strneq - compare null terminated @str to a non null terminated substring
* @str: a null terminated string
* @sub: a substring, not necessarily null terminated
* @len: length of @sub to compare
*
* The @str string must be full consumed for this to be considered a match
*/
static inline bool aa_strneq(const char *str, const char *sub, int len)
{
return !strncmp(str, sub, len) && !str[len];
}
/**
* aa_dfa_null_transition - step to next state after null character
* @dfa: the dfa to match against
* @start: the state of the dfa to start matching in
*
* aa_dfa_null_transition transitions to the next state after a null
* character which is not used in standard matching and is only
* used to separate pairs.
*/
static inline unsigned int aa_dfa_null_transition(struct aa_dfa *dfa,
unsigned int start)
{
/* the null transition only needs the string's null terminator byte */
return aa_dfa_next(dfa, start, 0);
}
static inline bool mediated_filesystem(struct dentry *dentry)
{
return !(dentry->d_sb->s_flags & MS_NOUSER);
}
/* struct aa_policy - common part of both namespaces and profiles
* @name: name of the object
* @hname - The hierarchical name
* @list: list policy object is on
* @profiles: head of the profiles list contained in the object
*/
struct aa_policy {
char *name;
char *hname;
struct list_head list;
struct list_head profiles;
};
/**
* hname_tail - find the last component of an hname
* @name: hname to find the base profile name component of (NOT NULL)
*
* Returns: the tail (base profile name) name component of an hname
*/
static inline const char *hname_tail(const char *hname)
{
char *split;
hname = strim((char *)hname);
for (split = strstr(hname, "//"); split; split = strstr(hname, "//"))
hname = split + 2;
return hname;
}
/**
* __policy_find - find a policy by @name on a policy list
* @head: list to search (NOT NULL)
* @name: name to search for (NOT NULL)
*
* Requires: rcu_read_lock be held
*
* Returns: unrefcounted policy that match @name or NULL if not found
*/
static inline struct aa_policy *__policy_find(struct list_head *head,
const char *name)
{
struct aa_policy *policy;
list_for_each_entry_rcu(policy, head, list) {
if (!strcmp(policy->name, name))
return policy;
}
return NULL;
}
/**
* __policy_strn_find - find a policy that's name matches @len chars of @str
* @head: list to search (NOT NULL)
* @str: string to search for (NOT NULL)
* @len: length of match required
*
* Requires: rcu_read_lock be held
*
* Returns: unrefcounted policy that match @str or NULL if not found
*
* if @len == strlen(@strlen) then this is equiv to __policy_find
* other wise it allows searching for policy by a partial match of name
*/
static inline struct aa_policy *__policy_strn_find(struct list_head *head,
const char *str, int len)
{
struct aa_policy *policy;
list_for_each_entry_rcu(policy, head, list) {
if (aa_strneq(policy->name, str, len))
return policy;
}
return NULL;
}
bool aa_policy_init(struct aa_policy *policy, const char *prefix,
const char *name);
void aa_policy_destroy(struct aa_policy *policy);
#endif /* AA_LIB_H */
|
