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
|
/*
* AppArmor security module
*
* This file contains AppArmor capability mediation functions
*
* 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.
*/
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/security.h>
#include "include/apparmor.h"
#include "include/capability.h"
#include "include/cred.h"
#include "include/policy.h"
#include "include/audit.h"
/*
* Table of capability names: we generate it from capabilities.h.
*/
#include "capability_names.h"
struct aa_sfs_entry aa_sfs_entry_caps[] = {
AA_SFS_FILE_STRING("mask", AA_SFS_CAPS_MASK),
{ }
};
struct audit_cache {
struct aa_profile *profile;
kernel_cap_t caps;
};
static DEFINE_PER_CPU(struct audit_cache, audit_cache);
/**
* audit_cb - call back for capability components of audit struct
* @ab - audit buffer (NOT NULL)
* @va - audit struct to audit data from (NOT NULL)
*/
static void audit_cb(struct audit_buffer *ab, void *va)
{
struct common_audit_data *sa = va;
audit_log_format(ab, " capname=");
audit_log_untrustedstring(ab, capability_names[sa->u.cap]);
}
/**
* audit_caps - audit a capability
* @sa: audit data
* @profile: profile being tested for confinement (NOT NULL)
* @cap: capability tested
* @error: error code returned by test
*
* Do auditing of capability and handle, audit/complain/kill modes switching
* and duplicate message elimination.
*
* Returns: 0 or sa->error on success, error code on failure
*/
static int audit_caps(struct common_audit_data *sa, struct aa_profile *profile,
int cap, int error)
{
struct audit_cache *ent;
int type = AUDIT_APPARMOR_AUTO;
aad(sa)->error = error;
if (likely(!error)) {
/* test if auditing is being forced */
if (likely((AUDIT_MODE(profile) != AUDIT_ALL) &&
!cap_raised(profile->caps.audit, cap)))
return 0;
type = AUDIT_APPARMOR_AUDIT;
} else if (KILL_MODE(profile) ||
cap_raised(profile->caps.kill, cap)) {
type = AUDIT_APPARMOR_KILL;
} else if (cap_raised(profile->caps.quiet, cap) &&
AUDIT_MODE(profile) != AUDIT_NOQUIET &&
AUDIT_MODE(profile) != AUDIT_ALL) {
/* quiet auditing */
return error;
}
/* Do simple duplicate message elimination */
ent = &get_cpu_var(audit_cache);
if (profile == ent->profile && cap_raised(ent->caps, cap)) {
put_cpu_var(audit_cache);
if (COMPLAIN_MODE(profile))
return complain_error(error);
return error;
} else {
aa_put_profile(ent->profile);
ent->profile = aa_get_profile(profile);
cap_raise(ent->caps, cap);
}
put_cpu_var(audit_cache);
return aa_audit(type, profile, sa, audit_cb);
}
/**
* profile_capable - test if profile allows use of capability @cap
* @profile: profile being enforced (NOT NULL, NOT unconfined)
* @cap: capability to test if allowed
* @opts: CAP_OPT_NOAUDIT bit determines whether audit record is generated
* @sa: audit data (MAY BE NULL indicating no auditing)
*
* Returns: 0 if allowed else -EPERM
*/
static int profile_capable(struct aa_profile *profile, int cap,
unsigned int opts, struct common_audit_data *sa)
{
int error;
if (cap_raised(profile->caps.allow, cap) &&
!cap_raised(profile->caps.denied, cap))
error = 0;
else
error = -EPERM;
if (opts & CAP_OPT_NOAUDIT) {
if (!COMPLAIN_MODE(profile))
return error;
/* audit the cap request in complain mode but note that it
* should be optional.
*/
aad(sa)->info = "optional: no audit";
}
return audit_caps(sa, profile, cap, error);
}
/**
* aa_capable - test permission to use capability
* @label: label being tested for capability (NOT NULL)
* @cap: capability to be tested
* @opts: CAP_OPT_NOAUDIT bit determines whether audit record is generated
*
* Look up capability in profile capability set.
*
* Returns: 0 on success, or else an error code.
*/
int aa_capable(struct aa_label *label, int cap, unsigned int opts)
{
struct aa_profile *profile;
int error = 0;
DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_CAP, OP_CAPABLE);
sa.u.cap = cap;
error = fn_for_each_confined(label, profile,
profile_capable(profile, cap, opts, &sa));
return error;
}
|
