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-rw-r--r--Documentation/kernel-parameters.txt2
-rw-r--r--security/integrity/ima/ima.h9
-rw-r--r--security/integrity/ima/ima_api.c5
-rw-r--r--security/integrity/ima/ima_appraise.c6
-rw-r--r--security/integrity/ima/ima_init.c25
-rw-r--r--security/integrity/ima/ima_main.c73
-rw-r--r--security/integrity/ima/ima_policy.c23
7 files changed, 95 insertions, 48 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 0cd50491..802a3fd 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1292,7 +1292,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Set number of hash buckets for inode cache.
ima_appraise= [IMA] appraise integrity measurements
- Format: { "off" | "enforce" | "fix" }
+ Format: { "off" | "enforce" | "fix" | "log" }
default: "enforce"
ima_appraise_tcb [IMA]
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 8e4bb88..8ee997d 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -43,6 +43,9 @@ enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
#define IMA_TEMPLATE_IMA_NAME "ima"
#define IMA_TEMPLATE_IMA_FMT "d|n"
+/* current content of the policy */
+extern int ima_policy_flag;
+
/* set during initialization */
extern int ima_initialized;
extern int ima_used_chip;
@@ -153,14 +156,16 @@ int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
int flags);
void ima_init_policy(void);
void ima_update_policy(void);
+void ima_update_policy_flag(void);
ssize_t ima_parse_add_rule(char *);
void ima_delete_rules(void);
/* Appraise integrity measurements */
#define IMA_APPRAISE_ENFORCE 0x01
#define IMA_APPRAISE_FIX 0x02
-#define IMA_APPRAISE_MODULES 0x04
-#define IMA_APPRAISE_FIRMWARE 0x08
+#define IMA_APPRAISE_LOG 0x04
+#define IMA_APPRAISE_MODULES 0x08
+#define IMA_APPRAISE_FIRMWARE 0x10
#ifdef CONFIG_IMA_APPRAISE
int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 65c41a9..8688597 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -179,11 +179,6 @@ int ima_get_action(struct inode *inode, int mask, int function)
return ima_match_policy(inode, function, mask, flags);
}
-int ima_must_measure(struct inode *inode, int mask, int function)
-{
- return ima_match_policy(inode, function, mask, IMA_MEASURE);
-}
-
/*
* ima_collect_measurement - collect file measurement
*
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 013ec3f..9226854 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -23,6 +23,8 @@ static int __init default_appraise_setup(char *str)
{
if (strncmp(str, "off", 3) == 0)
ima_appraise = 0;
+ else if (strncmp(str, "log", 3) == 0)
+ ima_appraise = IMA_APPRAISE_LOG;
else if (strncmp(str, "fix", 3) == 0)
ima_appraise = IMA_APPRAISE_FIX;
return 1;
@@ -316,7 +318,7 @@ void ima_inode_post_setattr(struct dentry *dentry)
struct integrity_iint_cache *iint;
int must_appraise, rc;
- if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode)
+ if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)
|| !inode->i_op->removexattr)
return;
@@ -354,7 +356,7 @@ static void ima_reset_appraise_flags(struct inode *inode, int digsig)
{
struct integrity_iint_cache *iint;
- if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode))
+ if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode))
return;
iint = integrity_iint_find(inode);
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index e8f9d70..9164fc8 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -43,7 +43,7 @@ int ima_used_chip;
* a different value.) Violations add a zero entry to the measurement
* list and extend the aggregate PCR value with ff...ff's.
*/
-static void __init ima_add_boot_aggregate(void)
+static int __init ima_add_boot_aggregate(void)
{
static const char op[] = "add_boot_aggregate";
const char *audit_cause = "ENOMEM";
@@ -72,17 +72,23 @@ static void __init ima_add_boot_aggregate(void)
result = ima_alloc_init_template(iint, NULL, boot_aggregate_name,
NULL, 0, &entry);
- if (result < 0)
- return;
+ if (result < 0) {
+ audit_cause = "alloc_entry";
+ goto err_out;
+ }
result = ima_store_template(entry, violation, NULL,
boot_aggregate_name);
- if (result < 0)
+ if (result < 0) {
ima_free_template_entry(entry);
- return;
+ audit_cause = "store_entry";
+ goto err_out;
+ }
+ return 0;
err_out:
integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL, boot_aggregate_name, op,
audit_cause, result, 0);
+ return result;
}
int __init ima_init(void)
@@ -98,6 +104,10 @@ int __init ima_init(void)
if (!ima_used_chip)
pr_info("No TPM chip found, activating TPM-bypass!\n");
+ rc = ima_init_keyring(INTEGRITY_KEYRING_IMA);
+ if (rc)
+ return rc;
+
rc = ima_init_crypto();
if (rc)
return rc;
@@ -105,7 +115,10 @@ int __init ima_init(void)
if (rc != 0)
return rc;
- ima_add_boot_aggregate(); /* boot aggregate must be first entry */
+ rc = ima_add_boot_aggregate(); /* boot aggregate must be first entry */
+ if (rc != 0)
+ return rc;
+
ima_init_policy();
return ima_fs_init();
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 673a37e..62f59ec 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -77,42 +77,39 @@ __setup("ima_hash=", hash_setup);
* could result in a file measurement error.
*
*/
-static void ima_rdwr_violation_check(struct file *file)
+static void ima_rdwr_violation_check(struct file *file,
+ struct integrity_iint_cache *iint,
+ int must_measure,
+ char **pathbuf,
+ const char **pathname)
{
struct inode *inode = file_inode(file);
fmode_t mode = file->f_mode;
bool send_tomtou = false, send_writers = false;
- char *pathbuf = NULL;
- const char *pathname;
-
- if (!S_ISREG(inode->i_mode) || !ima_initialized)
- return;
if (mode & FMODE_WRITE) {
if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
- struct integrity_iint_cache *iint;
- iint = integrity_iint_find(inode);
+ if (!iint)
+ iint = integrity_iint_find(inode);
/* IMA_MEASURE is set from reader side */
if (iint && (iint->flags & IMA_MEASURE))
send_tomtou = true;
}
} else {
- if ((atomic_read(&inode->i_writecount) > 0) &&
- ima_must_measure(inode, MAY_READ, FILE_CHECK))
+ if ((atomic_read(&inode->i_writecount) > 0) && must_measure)
send_writers = true;
}
if (!send_tomtou && !send_writers)
return;
- pathname = ima_d_path(&file->f_path, &pathbuf);
+ *pathname = ima_d_path(&file->f_path, pathbuf);
if (send_tomtou)
- ima_add_violation(file, pathname, "invalid_pcr", "ToMToU");
+ ima_add_violation(file, *pathname, "invalid_pcr", "ToMToU");
if (send_writers)
- ima_add_violation(file, pathname,
+ ima_add_violation(file, *pathname,
"invalid_pcr", "open_writers");
- kfree(pathbuf);
}
static void ima_check_last_writer(struct integrity_iint_cache *iint,
@@ -160,15 +157,16 @@ static int process_measurement(struct file *file, int mask, int function,
int opened)
{
struct inode *inode = file_inode(file);
- struct integrity_iint_cache *iint;
+ struct integrity_iint_cache *iint = NULL;
struct ima_template_desc *template_desc;
char *pathbuf = NULL;
const char *pathname = NULL;
int rc = -ENOMEM, action, must_appraise;
struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL;
int xattr_len = 0;
+ bool violation_check;
- if (!ima_initialized || !S_ISREG(inode->i_mode))
+ if (!ima_policy_flag || !S_ISREG(inode->i_mode))
return 0;
/* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action
@@ -176,7 +174,9 @@ static int process_measurement(struct file *file, int mask, int function,
* Included is the appraise submask.
*/
action = ima_get_action(inode, mask, function);
- if (!action)
+ violation_check = ((function == FILE_CHECK || function == MMAP_CHECK) &&
+ (ima_policy_flag & IMA_MEASURE));
+ if (!action && !violation_check)
return 0;
must_appraise = action & IMA_APPRAISE;
@@ -187,9 +187,20 @@ static int process_measurement(struct file *file, int mask, int function,
mutex_lock(&inode->i_mutex);
- iint = integrity_inode_get(inode);
- if (!iint)
- goto out;
+ if (action) {
+ iint = integrity_inode_get(inode);
+ if (!iint)
+ goto out;
+ }
+
+ if (violation_check) {
+ ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
+ &pathbuf, &pathname);
+ if (!action) {
+ rc = 0;
+ goto out_free;
+ }
+ }
/* Determine if already appraised/measured based on bitmask
* (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
@@ -218,7 +229,8 @@ static int process_measurement(struct file *file, int mask, int function,
goto out_digsig;
}
- pathname = ima_d_path(&file->f_path, &pathbuf);
+ if (!pathname) /* ima_rdwr_violation possibly pre-fetched */
+ pathname = ima_d_path(&file->f_path, &pathbuf);
if (action & IMA_MEASURE)
ima_store_measurement(iint, file, pathname,
@@ -228,13 +240,15 @@ static int process_measurement(struct file *file, int mask, int function,
xattr_value, xattr_len, opened);
if (action & IMA_AUDIT)
ima_audit_measurement(iint, pathname);
- kfree(pathbuf);
+
out_digsig:
if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG))
rc = -EACCES;
+ kfree(xattr_value);
+out_free:
+ kfree(pathbuf);
out:
mutex_unlock(&inode->i_mutex);
- kfree(xattr_value);
if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE))
return -EACCES;
return 0;
@@ -288,7 +302,6 @@ int ima_bprm_check(struct linux_binprm *bprm)
*/
int ima_file_check(struct file *file, int mask, int opened)
{
- ima_rdwr_violation_check(file);
return process_measurement(file,
mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
FILE_CHECK, opened);
@@ -334,14 +347,10 @@ static int __init init_ima(void)
hash_setup(CONFIG_IMA_DEFAULT_HASH);
error = ima_init();
- if (error)
- goto out;
-
- error = ima_init_keyring(INTEGRITY_KEYRING_IMA);
- if (error)
- goto out;
- ima_initialized = 1;
-out:
+ if (!error) {
+ ima_initialized = 1;
+ ima_update_policy_flag();
+ }
return error;
}
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 07099a8..cdc620b 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
@@ -295,6 +297,26 @@ 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.
*
@@ -341,6 +363,7 @@ void ima_update_policy(void)
if (ima_rules == &ima_default_rules) {
ima_rules = &ima_policy_rules;
+ ima_update_policy_flag();
cause = "complete";
result = 0;
}
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