diff options
Diffstat (limited to 'security/integrity/ima/ima_policy.c')
-rw-r--r-- | security/integrity/ima/ima_policy.c | 72 |
1 files changed, 44 insertions, 28 deletions
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 40a7488f6721..d1eefb9d65fb 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -35,6 +35,8 @@ #define DONT_APPRAISE 0x0008 #define AUDIT 0x0040 +int ima_policy_flag; + #define MAX_LSM_RULES 6 enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE, LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE @@ -84,6 +86,7 @@ static struct ima_rule_entry default_rules[] = { {.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ, .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_MASK | IMA_UID}, {.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC}, + {.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC}, }; static struct ima_rule_entry default_appraise_rules[] = { @@ -97,7 +100,13 @@ static struct ima_rule_entry default_appraise_rules[] = { {.action = DONT_APPRAISE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC}, +#ifndef CONFIG_IMA_APPRAISE_SIGNED_INIT {.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .flags = IMA_FOWNER}, +#else + /* force signature */ + {.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, + .flags = IMA_FOWNER | IMA_DIGSIG_REQUIRED}, +#endif }; static LIST_HEAD(ima_default_rules); @@ -241,6 +250,8 @@ static int get_subaction(struct ima_rule_entry *rule, int func) return IMA_BPRM_APPRAISE; case MODULE_CHECK: return IMA_MODULE_APPRAISE; + case FIRMWARE_CHECK: + return IMA_FIRMWARE_APPRAISE; case FILE_CHECK: default: return IMA_FILE_APPRAISE; @@ -292,6 +303,26 @@ int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, return action; } +/* + * Initialize the ima_policy_flag variable based on the currently + * loaded policy. Based on this flag, the decision to short circuit + * out of a function or not call the function in the first place + * can be made earlier. + */ +void ima_update_policy_flag(void) +{ + struct ima_rule_entry *entry; + + ima_policy_flag = 0; + list_for_each_entry(entry, ima_rules, list) { + if (entry->action & IMA_DO_MASK) + ima_policy_flag |= entry->action; + } + + if (!ima_appraise) + ima_policy_flag &= ~IMA_APPRAISE; +} + /** * ima_init_policy - initialize the default measure rules. * @@ -331,18 +362,8 @@ void __init ima_init_policy(void) */ void ima_update_policy(void) { - static const char op[] = "policy_update"; - const char *cause = "already exists"; - int result = 1; - int audit_info = 0; - - if (ima_rules == &ima_default_rules) { - ima_rules = &ima_policy_rules; - cause = "complete"; - result = 0; - } - integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, - NULL, op, cause, result, audit_info); + ima_rules = &ima_policy_rules; + ima_update_policy_flag(); } enum { @@ -486,6 +507,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->func = FILE_CHECK; else if (strcmp(args[0].from, "MODULE_CHECK") == 0) entry->func = MODULE_CHECK; + else if (strcmp(args[0].from, "FIRMWARE_CHECK") == 0) + entry->func = FIRMWARE_CHECK; else if ((strcmp(args[0].from, "FILE_MMAP") == 0) || (strcmp(args[0].from, "MMAP_CHECK") == 0)) entry->func = MMAP_CHECK; @@ -636,6 +659,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) result = -EINVAL; else if (entry->func == MODULE_CHECK) ima_appraise |= IMA_APPRAISE_MODULES; + else if (entry->func == FIRMWARE_CHECK) + ima_appraise |= IMA_APPRAISE_FIRMWARE; audit_log_format(ab, "res=%d", !result); audit_log_end(ab); return result; @@ -656,13 +681,12 @@ ssize_t ima_parse_add_rule(char *rule) ssize_t result, len; int audit_info = 0; - /* Prevent installed policy from changing */ - if (ima_rules != &ima_default_rules) { - integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, - NULL, op, "already exists", - -EACCES, audit_info); - return -EACCES; - } + p = strsep(&rule, "\n"); + len = strlen(p) + 1; + p += strspn(p, " \t"); + + if (*p == '#' || *p == '\0') + return len; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (!entry) { @@ -673,19 +697,11 @@ ssize_t ima_parse_add_rule(char *rule) INIT_LIST_HEAD(&entry->list); - p = strsep(&rule, "\n"); - len = strlen(p) + 1; - - if (*p == '#') { - kfree(entry); - return len; - } - result = ima_parse_rule(p, entry); if (result) { kfree(entry); integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, - NULL, op, "invalid policy", result, + NULL, op, "invalid-policy", result, audit_info); return result; } |