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
|
From: Mimi Zohar <zohar@linux.vnet.ibm.com>
Date: Wed, 8 Nov 2017 15:11:32 +0000
Subject: [03/29] ima: require secure_boot rules in lockdown mode
Origin: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit?id=29c55d71a8185208c7962843a29c9a84ae27b2b0
Require the "secure_boot" rules, whether or not it is specified
on the boot command line, for both the builtin and custom policies
in secure boot lockdown mode.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
[bwh: Adjust context to apply after commits 6f0911a666d1
"ima: fix updating the ima_appraise flag" and ef96837b0de4
"ima: add build time policy"]
---
security/integrity/ima/ima_policy.c | 39 +++++++++++++++++++++++++++----------
1 file changed, 29 insertions(+), 10 deletions(-)
Index: linux/security/integrity/ima/ima_policy.c
===================================================================
--- linux.orig/security/integrity/ima/ima_policy.c
+++ linux/security/integrity/ima/ima_policy.c
@@ -481,14 +481,21 @@ static int ima_appraise_flag(enum ima_ho
*/
void __init ima_init_policy(void)
{
- int i, measure_entries, appraise_entries, secure_boot_entries;
+ int i;
+ int measure_entries = 0;
+ int appraise_entries = 0;
+ int secure_boot_entries = 0;
+ bool kernel_locked_down = __kernel_is_locked_down(NULL, false);
/* if !ima_policy set entries = 0 so we load NO default rules */
- measure_entries = ima_policy ? ARRAY_SIZE(dont_measure_rules) : 0;
- appraise_entries = ima_use_appraise_tcb ?
- ARRAY_SIZE(default_appraise_rules) : 0;
- secure_boot_entries = ima_use_secure_boot ?
- ARRAY_SIZE(secure_boot_rules) : 0;
+ if (ima_policy)
+ measure_entries = ARRAY_SIZE(dont_measure_rules);
+
+ if (ima_use_appraise_tcb)
+ appraise_entries = ARRAY_SIZE(default_appraise_rules);
+
+ if (ima_use_secure_boot || kernel_locked_down)
+ secure_boot_entries = ARRAY_SIZE(secure_boot_rules);
for (i = 0; i < measure_entries; i++)
list_add_tail(&dont_measure_rules[i].list, &ima_default_rules);
@@ -510,11 +517,24 @@ void __init ima_init_policy(void)
/*
* Insert the builtin "secure_boot" policy rules requiring file
* signatures, prior to any other appraise rules.
+ * In secure boot lock-down mode, also require these appraise
+ * rules for custom policies.
*/
for (i = 0; i < secure_boot_entries; i++) {
+ struct ima_rule_entry *entry;
+
+ /* Include for builtin policies */
list_add_tail(&secure_boot_rules[i].list, &ima_default_rules);
temp_ima_appraise |=
ima_appraise_flag(secure_boot_rules[i].func);
+
+ /* Include for custom policies */
+ if (kernel_locked_down) {
+ entry = kmemdup(&secure_boot_rules[i], sizeof(*entry),
+ GFP_KERNEL);
+ if (entry)
+ list_add_tail(&entry->list, &ima_policy_rules);
+ }
}
/*
|
