diff options
author | Nayna Jain <nayna@linux.ibm.com> | 2018-10-09 23:00:35 +0530 |
---|---|---|
committer | Mimi Zohar <zohar@linux.ibm.com> | 2018-12-11 07:13:39 -0500 |
commit | c52657d93b0530449233979514a08cf9fe5c24bc (patch) | |
tree | a8908f484fa957cca1425c21853652da622c9cdd /security/integrity/ima/ima_policy.c | |
parent | b5ca117365d960fe5e4fe272bcc8142c28769383 (diff) | |
download | linux-c52657d93b0530449233979514a08cf9fe5c24bc.tar.bz2 |
ima: refactor ima_init_policy()
This patch removes the code duplication in ima_init_policy() by defining
a new function named add_rules(). The new function adds the rules to the
initial IMA policy, the custom policy or both based on the policy mask
(IMA_DEFAULT_POLICY, IMA_CUSTOM_POLICY).
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Diffstat (limited to 'security/integrity/ima/ima_policy.c')
-rw-r--r-- | security/integrity/ima/ima_policy.c | 97 |
1 files changed, 56 insertions, 41 deletions
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 8c9499867c91..1e30d09a56db 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -58,6 +58,8 @@ enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE, enum policy_types { ORIGINAL_TCB = 1, DEFAULT_TCB }; +enum policy_rule_list { IMA_DEFAULT_POLICY = 1, IMA_CUSTOM_POLICY }; + struct ima_rule_entry { struct list_head list; int action; @@ -473,6 +475,32 @@ static int ima_appraise_flag(enum ima_hooks func) return 0; } +static void add_rules(struct ima_rule_entry *entries, int count, + enum policy_rule_list policy_rule) +{ + int i = 0; + + for (i = 0; i < count; i++) { + struct ima_rule_entry *entry; + + if (policy_rule & IMA_DEFAULT_POLICY) + list_add_tail(&entries[i].list, &ima_default_rules); + + if (policy_rule & IMA_CUSTOM_POLICY) { + entry = kmemdup(&entries[i], sizeof(*entry), + GFP_KERNEL); + if (!entry) + continue; + + list_add_tail(&entry->list, &ima_policy_rules); + } + if (entries[i].action == APPRAISE) + temp_ima_appraise |= ima_appraise_flag(entries[i].func); + if (entries[i].func == POLICY_CHECK) + temp_ima_appraise |= IMA_APPRAISE_POLICY; + } +} + /** * ima_init_policy - initialize the default measure rules. * @@ -481,28 +509,23 @@ static int ima_appraise_flag(enum ima_hooks func) */ void __init ima_init_policy(void) { - int i, measure_entries, appraise_entries, secure_boot_entries; - - /* 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; + int build_appraise_entries; - for (i = 0; i < measure_entries; i++) - list_add_tail(&dont_measure_rules[i].list, &ima_default_rules); + /* if !ima_policy, we load NO default rules */ + if (ima_policy) + add_rules(dont_measure_rules, ARRAY_SIZE(dont_measure_rules), + IMA_DEFAULT_POLICY); switch (ima_policy) { case ORIGINAL_TCB: - for (i = 0; i < ARRAY_SIZE(original_measurement_rules); i++) - list_add_tail(&original_measurement_rules[i].list, - &ima_default_rules); + add_rules(original_measurement_rules, + ARRAY_SIZE(original_measurement_rules), + IMA_DEFAULT_POLICY); break; case DEFAULT_TCB: - for (i = 0; i < ARRAY_SIZE(default_measurement_rules); i++) - list_add_tail(&default_measurement_rules[i].list, - &ima_default_rules); + add_rules(default_measurement_rules, + ARRAY_SIZE(default_measurement_rules), + IMA_DEFAULT_POLICY); default: break; } @@ -511,38 +534,30 @@ void __init ima_init_policy(void) * Insert the builtin "secure_boot" policy rules requiring file * signatures, prior to any other appraise rules. */ - for (i = 0; i < secure_boot_entries; i++) { - list_add_tail(&secure_boot_rules[i].list, &ima_default_rules); - temp_ima_appraise |= - ima_appraise_flag(secure_boot_rules[i].func); - } + if (ima_use_secure_boot) + add_rules(secure_boot_rules, ARRAY_SIZE(secure_boot_rules), + IMA_DEFAULT_POLICY); /* * Insert the build time appraise rules requiring file signatures * for both the initial and custom policies, prior to other appraise - * rules. + * rules. As the secure boot rules includes all of the build time + * rules, include either one or the other set of rules, but not both. */ - for (i = 0; i < ARRAY_SIZE(build_appraise_rules); i++) { - struct ima_rule_entry *entry; - - if (!secure_boot_entries) - list_add_tail(&build_appraise_rules[i].list, - &ima_default_rules); - - entry = kmemdup(&build_appraise_rules[i], sizeof(*entry), - GFP_KERNEL); - if (entry) - list_add_tail(&entry->list, &ima_policy_rules); - build_ima_appraise |= - ima_appraise_flag(build_appraise_rules[i].func); + build_appraise_entries = ARRAY_SIZE(build_appraise_rules); + if (build_appraise_entries) { + if (ima_use_secure_boot) + add_rules(build_appraise_rules, build_appraise_entries, + IMA_CUSTOM_POLICY); + else + add_rules(build_appraise_rules, build_appraise_entries, + IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY); } - for (i = 0; i < appraise_entries; i++) { - list_add_tail(&default_appraise_rules[i].list, - &ima_default_rules); - if (default_appraise_rules[i].func == POLICY_CHECK) - temp_ima_appraise |= IMA_APPRAISE_POLICY; - } + if (ima_use_appraise_tcb) + add_rules(default_appraise_rules, + ARRAY_SIZE(default_appraise_rules), + IMA_DEFAULT_POLICY); ima_rules = &ima_default_rules; ima_update_policy_flag(); |