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
216
217
|
/*
* AppArmor security module
*
* This file contains AppArmor file mediation function definitions.
*
* Copyright (C) 1998-2008 Novell/SUSE
* Copyright 2009-2010 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_FILE_H
#define __AA_FILE_H
#include "domain.h"
#include "match.h"
struct aa_profile;
struct path;
/*
* We use MAY_EXEC, MAY_WRITE, MAY_READ, MAY_APPEND and the following flags
* for profile permissions
*/
#define AA_MAY_CREATE 0x0010
#define AA_MAY_DELETE 0x0020
#define AA_MAY_META_WRITE 0x0040
#define AA_MAY_META_READ 0x0080
#define AA_MAY_CHMOD 0x0100
#define AA_MAY_CHOWN 0x0200
#define AA_MAY_LOCK 0x0400
#define AA_EXEC_MMAP 0x0800
#define AA_MAY_LINK 0x1000
#define AA_LINK_SUBSET AA_MAY_LOCK /* overlaid */
#define AA_MAY_ONEXEC 0x40000000 /* exec allows onexec */
#define AA_MAY_CHANGE_PROFILE 0x80000000
#define AA_MAY_CHANGEHAT 0x80000000 /* ctrl auditing only */
#define AA_AUDIT_FILE_MASK (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
AA_MAY_CREATE | AA_MAY_DELETE | \
AA_MAY_META_READ | AA_MAY_META_WRITE | \
AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
AA_EXEC_MMAP | AA_MAY_LINK)
/*
* The xindex is broken into 3 parts
* - index - an index into either the exec name table or the variable table
* - exec type - which determines how the executable name and index are used
* - flags - which modify how the destination name is applied
*/
#define AA_X_INDEX_MASK 0x03ff
#define AA_X_TYPE_MASK 0x0c00
#define AA_X_TYPE_SHIFT 10
#define AA_X_NONE 0x0000
#define AA_X_NAME 0x0400 /* use executable name px */
#define AA_X_TABLE 0x0800 /* use a specified name ->n# */
#define AA_X_UNSAFE 0x1000
#define AA_X_CHILD 0x2000 /* make >AA_X_NONE apply to children */
#define AA_X_INHERIT 0x4000
#define AA_X_UNCONFINED 0x8000
/* AA_SECURE_X_NEEDED - is passed in the bprm->unsafe field */
#define AA_SECURE_X_NEEDED 0x8000
/* need to make conditional which ones are being set */
struct path_cond {
kuid_t uid;
umode_t mode;
};
/* struct file_perms - file permission
* @allow: mask of permissions that are allowed
* @audit: mask of permissions to force an audit message for
* @quiet: mask of permissions to quiet audit messages for
* @kill: mask of permissions that when matched will kill the task
* @xindex: exec transition index if @allow contains MAY_EXEC
*
* The @audit and @queit mask should be mutually exclusive.
*/
struct file_perms {
u32 allow;
u32 audit;
u32 quiet;
u32 kill;
u16 xindex;
};
extern struct file_perms nullperms;
#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
/* FIXME: split perms from dfa and match this to description
* also add delegation info.
*/
static inline u16 dfa_map_xindex(u16 mask)
{
u16 old_index = (mask >> 10) & 0xf;
u16 index = 0;
if (mask & 0x100)
index |= AA_X_UNSAFE;
if (mask & 0x200)
index |= AA_X_INHERIT;
if (mask & 0x80)
index |= AA_X_UNCONFINED;
if (old_index == 1) {
index |= AA_X_UNCONFINED;
} else if (old_index == 2) {
index |= AA_X_NAME;
} else if (old_index == 3) {
index |= AA_X_NAME | AA_X_CHILD;
} else if (old_index) {
index |= AA_X_TABLE;
index |= old_index - 4;
}
return index;
}
/*
* map old dfa inline permissions to new format
*/
#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) | \
((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
#define dfa_user_xindex(dfa, state) \
(dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
0x7f) | \
((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
#define dfa_other_quiet(dfa, state) \
((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
#define dfa_other_xindex(dfa, state) \
dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
int aa_audit_file(struct aa_profile *profile, struct file_perms *perms,
gfp_t gfp, const char *op, u32 request, const char *name,
const char *target, kuid_t ouid, const char *info, int error);
/**
* struct aa_file_rules - components used for file rule permissions
* @dfa: dfa to match path names and conditionals against
* @perms: permission table indexed by the matched state accept entry of @dfa
* @trans: transition table for indexed by named x transitions
*
* File permission are determined by matching a path against @dfa and then
* then using the value of the accept entry for the matching state as
* an index into @perms. If a named exec transition is required it is
* looked up in the transition table.
*/
struct aa_file_rules {
unsigned int start;
struct aa_dfa *dfa;
/* struct perms perms; */
struct aa_domain trans;
/* TODO: add delegate table */
};
unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
const char *name, struct path_cond *cond,
struct file_perms *perms);
int aa_path_perm(const char *op, struct aa_profile *profile,
const struct path *path, int flags, u32 request,
struct path_cond *cond);
int aa_path_link(struct aa_profile *profile, struct dentry *old_dentry,
const struct path *new_dir, struct dentry *new_dentry);
int aa_file_perm(const char *op, struct aa_profile *profile, struct file *file,
u32 request);
static inline void aa_free_file_rules(struct aa_file_rules *rules)
{
aa_put_dfa(rules->dfa);
aa_free_domain_entries(&rules->trans);
}
/**
* aa_map_file_perms - map file flags to AppArmor permissions
* @file: open file to map flags to AppArmor permissions
*
* Returns: apparmor permission set for the file
*/
static inline u32 aa_map_file_to_perms(struct file *file)
{
int flags = file->f_flags;
u32 perms = 0;
if (file->f_mode & FMODE_WRITE)
perms |= MAY_WRITE;
if (file->f_mode & FMODE_READ)
perms |= MAY_READ;
if ((flags & O_APPEND) && (perms & MAY_WRITE))
perms = (perms & ~MAY_WRITE) | MAY_APPEND;
/* trunc implies write permission */
if (flags & O_TRUNC)
perms |= MAY_WRITE;
if (flags & O_CREAT)
perms |= AA_MAY_CREATE;
return perms;
}
#endif /* __AA_FILE_H */
|
