diff options
Diffstat (limited to 'security/integrity/ima/ima_policy.c')
-rw-r--r-- | security/integrity/ima/ima_policy.c | 32 |
1 files changed, 23 insertions, 9 deletions
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 915f5572c6ff..d89bebf85421 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -96,6 +96,7 @@ static struct ima_rule_entry dont_measure_rules[] __ro_after_init = { {.action = DONT_MEASURE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_MEASURE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_MEASURE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE, .fsmagic = SMACK_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_MEASURE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_MEASURE, .fsmagic = CGROUP2_SUPER_MAGIC, @@ -141,6 +142,7 @@ static struct ima_rule_entry default_appraise_rules[] __ro_after_init = { {.action = DONT_APPRAISE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC}, + {.action = DONT_APPRAISE, .fsmagic = SMACK_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC}, {.action = DONT_APPRAISE, .fsmagic = CGROUP2_SUPER_MAGIC, .flags = IMA_FSMAGIC}, @@ -188,6 +190,7 @@ __setup("ima_tcb", default_measure_policy_setup); static bool ima_use_appraise_tcb __initdata; static bool ima_use_secure_boot __initdata; +static bool ima_fail_unverifiable_sigs __ro_after_init; static int __init policy_setup(char *str) { char *p; @@ -201,6 +204,8 @@ static int __init policy_setup(char *str) ima_use_appraise_tcb = true; else if (strcmp(p, "secure_boot") == 0) ima_use_secure_boot = true; + else if (strcmp(p, "fail_securely") == 0) + ima_fail_unverifiable_sigs = true; } return 1; @@ -243,16 +248,17 @@ static void ima_lsm_update_rules(void) * ima_match_rules - determine whether an inode matches the measure rule. * @rule: a pointer to a rule * @inode: a pointer to an inode + * @cred: a pointer to a credentials structure for user validation + * @secid: the secid of the task to be validated * @func: LIM hook identifier * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) * * Returns true on rule match, false on failure. */ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, + const struct cred *cred, u32 secid, enum ima_hooks func, int mask) { - struct task_struct *tsk = current; - const struct cred *cred = current_cred(); int i; if ((rule->flags & IMA_FUNC) && @@ -287,7 +293,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, return false; for (i = 0; i < MAX_LSM_RULES; i++) { int rc = 0; - u32 osid, sid; + u32 osid; int retried = 0; if (!rule->lsm[i].rule) @@ -307,8 +313,7 @@ retry: case LSM_SUBJ_USER: case LSM_SUBJ_ROLE: case LSM_SUBJ_TYPE: - security_task_getsecid(tsk, &sid); - rc = security_filter_rule_match(sid, + rc = security_filter_rule_match(secid, rule->lsm[i].type, Audit_equal, rule->lsm[i].rule, @@ -341,6 +346,8 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func) return IMA_MMAP_APPRAISE; case BPRM_CHECK: return IMA_BPRM_APPRAISE; + case CREDS_CHECK: + return IMA_CREDS_APPRAISE; case FILE_CHECK: case POST_SETATTR: return IMA_FILE_APPRAISE; @@ -353,6 +360,9 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func) /** * ima_match_policy - decision based on LSM and other conditions * @inode: pointer to an inode for which the policy decision is being made + * @cred: pointer to a credentials structure for which the policy decision is + * being made + * @secid: LSM secid of the task to be validated * @func: IMA hook identifier * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) * @pcr: set the pcr to extend @@ -364,8 +374,8 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func) * list when walking it. Reads are many orders of magnitude more numerous * than writes so ima_match_policy() is classical RCU candidate. */ -int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, - int flags, int *pcr) +int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, + enum ima_hooks func, int mask, int flags, int *pcr) { struct ima_rule_entry *entry; int action = 0, actmask = flags | (flags << 1); @@ -376,7 +386,7 @@ int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, if (!(entry->action & actmask)) continue; - if (!ima_match_rules(entry, inode, func, mask)) + if (!ima_match_rules(entry, inode, cred, secid, func, mask)) continue; action |= entry->flags & IMA_ACTION_FLAGS; @@ -384,7 +394,9 @@ int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, action |= entry->action & IMA_DO_MASK; if (entry->action & IMA_APPRAISE) { action |= get_subaction(entry, func); - action ^= IMA_HASH; + action &= ~IMA_HASH; + if (ima_fail_unverifiable_sigs) + action |= IMA_FAIL_UNVERIFIABLE_SIGS; } if (entry->action & IMA_DO_MASK) @@ -713,6 +725,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->func = MMAP_CHECK; else if (strcmp(args[0].from, "BPRM_CHECK") == 0) entry->func = BPRM_CHECK; + else if (strcmp(args[0].from, "CREDS_CHECK") == 0) + entry->func = CREDS_CHECK; else if (strcmp(args[0].from, "KEXEC_KERNEL_CHECK") == 0) entry->func = KEXEC_KERNEL_CHECK; |