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
|
/*
* AppArmor security module
*
* This file contains basic common functions used in AppArmor
*
* 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/ctype.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include "include/audit.h"
#include "include/apparmor.h"
#include "include/lib.h"
#include "include/policy.h"
/**
* aa_split_fqname - split a fqname into a profile and namespace name
* @fqname: a full qualified name in namespace profile format (NOT NULL)
* @ns_name: pointer to portion of the string containing the ns name (NOT NULL)
*
* Returns: profile name or NULL if one is not specified
*
* Split a namespace name from a profile name (see policy.c for naming
* description). If a portion of the name is missing it returns NULL for
* that portion.
*
* NOTE: may modify the @fqname string. The pointers returned point
* into the @fqname string.
*/
char *aa_split_fqname(char *fqname, char **ns_name)
{
char *name = strim(fqname);
*ns_name = NULL;
if (name[0] == ':') {
char *split = strchr(&name[1], ':');
*ns_name = skip_spaces(&name[1]);
if (split) {
/* overwrite ':' with \0 */
*split++ = 0;
if (strncmp(split, "//", 2) == 0)
split += 2;
name = skip_spaces(split);
} else
/* a ns name without a following profile is allowed */
name = NULL;
}
if (name && *name == 0)
name = NULL;
return name;
}
/**
* skipn_spaces - Removes leading whitespace from @str.
* @str: The string to be stripped.
*
* Returns a pointer to the first non-whitespace character in @str.
* if all whitespace will return NULL
*/
static const char *skipn_spaces(const char *str, size_t n)
{
for (; n && isspace(*str); --n)
++str;
if (n)
return (char *)str;
return NULL;
}
const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name,
size_t *ns_len)
{
const char *end = fqname + n;
const char *name = skipn_spaces(fqname, n);
if (!name)
return NULL;
*ns_name = NULL;
*ns_len = 0;
if (name[0] == ':') {
char *split = strnchr(&name[1], end - &name[1], ':');
*ns_name = skipn_spaces(&name[1], end - &name[1]);
if (!*ns_name)
return NULL;
if (split) {
*ns_len = split - *ns_name;
if (*ns_len == 0)
*ns_name = NULL;
split++;
if (end - split > 1 && strncmp(split, "//", 2) == 0)
split += 2;
name = skipn_spaces(split, end - split);
} else {
/* a ns name without a following profile is allowed */
name = NULL;
*ns_len = end - *ns_name;
}
}
if (name && *name == 0)
name = NULL;
return name;
}
/**
* aa_info_message - log a none profile related status message
* @str: message to log
*/
void aa_info_message(const char *str)
{
if (audit_enabled) {
struct common_audit_data sa;
struct apparmor_audit_data aad = {0,};
sa.type = LSM_AUDIT_DATA_NONE;
sa.aad = &aad;
aad.info = str;
aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, NULL);
}
printk(KERN_INFO "AppArmor: %s\n", str);
}
/**
* __aa_kvmalloc - do allocation preferring kmalloc but falling back to vmalloc
* @size: how many bytes of memory are required
* @flags: the type of memory to allocate (see kmalloc).
*
* Return: allocated buffer or NULL if failed
*
* It is possible that policy being loaded from the user is larger than
* what can be allocated by kmalloc, in those cases fall back to vmalloc.
*/
void *__aa_kvmalloc(size_t size, gfp_t flags)
{
void *buffer = NULL;
if (size == 0)
return NULL;
/* do not attempt kmalloc if we need more than 16 pages at once */
if (size <= (16*PAGE_SIZE))
buffer = kmalloc(size, flags | GFP_KERNEL | __GFP_NORETRY |
__GFP_NOWARN);
if (!buffer) {
if (flags & __GFP_ZERO)
buffer = vzalloc(size);
else
buffer = vmalloc(size);
}
return buffer;
}
/**
* aa_policy_init - initialize a policy structure
* @policy: policy to initialize (NOT NULL)
* @prefix: prefix name if any is required. (MAYBE NULL)
* @name: name of the policy, init will make a copy of it (NOT NULL)
*
* Note: this fn creates a copy of strings passed in
*
* Returns: true if policy init successful
*/
bool aa_policy_init(struct aa_policy *policy, const char *prefix,
const char *name, gfp_t gfp)
{
/* freed by policy_free */
if (prefix) {
policy->hname = kmalloc(strlen(prefix) + strlen(name) + 3,
gfp);
if (policy->hname)
sprintf((char *)policy->hname, "%s//%s", prefix, name);
} else
policy->hname = kstrdup(name, gfp);
if (!policy->hname)
return 0;
/* base.name is a substring of fqname */
policy->name = basename(policy->hname);
INIT_LIST_HEAD(&policy->list);
INIT_LIST_HEAD(&policy->profiles);
return 1;
}
/**
* aa_policy_destroy - free the elements referenced by @policy
* @policy: policy that is to have its elements freed (NOT NULL)
*/
void aa_policy_destroy(struct aa_policy *policy)
{
AA_BUG(on_list_rcu(&policy->profiles));
AA_BUG(on_list_rcu(&policy->list));
/* don't free name as its a subset of hname */
kzfree(policy->hname);
}
|
