Defined functions to queue key for measurement if ima is not yet
initialized. ima hook function ima_post_key_create_or_update will
queue the key if ima is not yet initialized.
Process queued keys and measure them when ima initialization
is completed.
Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
---
security/integrity/ima/ima.h | 13 +++++
security/integrity/ima/ima_init.c | 9 ++-
security/integrity/ima/ima_main.c | 4 +-
security/integrity/ima/ima_queue.c | 94 ++++++++++++++++++++++++++++++
4 files changed, 118 insertions(+), 2 deletions(-)
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 2d4130ff5655..38279707632a 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -199,6 +199,17 @@ enum ima_hooks {
__ima_hooks(__ima_hook_enumify)
};
+/*
+ * To track trusted keys that need to be measured when IMA is initialized.
+ */
+struct ima_trusted_key_entry {
+ struct list_head list;
+ void *public_key;
+ u32 public_key_len;
+ char *key_description;
+ enum ima_hooks func;
+};
+
/* LIM API function definitions */
int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
int mask, enum ima_hooks func, int *pcr,
@@ -225,6 +236,8 @@ int ima_store_template(struct ima_template_entry *entry, int violation,
const unsigned char *filename, int pcr);
void ima_free_template_entry(struct ima_template_entry *entry);
const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
+int ima_queue_key_for_measurement(struct key *key, enum ima_hooks func);
+void ima_measure_queued_keys(void);
/* IMA policy related functions */
int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index 52847ce765a4..8734ed5322c7 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -132,5 +132,12 @@ int __init ima_init(void)
ima_init_policy();
- return ima_fs_init();
+ rc = ima_fs_init();
+ if (rc != 0)
+ return rc;
+
+ ima_initialized = true;
+
+ ima_measure_queued_keys();
+ return 0;
}
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 8bde12385912..bce430b3386e 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -710,8 +710,10 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key,
if (key->type != &key_type_asymmetric)
return;
- if (!ima_initialized)
+ if (!ima_initialized) {
+ ima_queue_key_for_measurement(key, NONE);
return;
+ }
pk = key->payload.data[asym_crypto];
process_buffer_measurement(pk->key, pk->keylen,
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 1ce8b1701566..d42987022c12 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -46,6 +46,13 @@ struct ima_h_table ima_htable = {
*/
static DEFINE_MUTEX(ima_extend_list_mutex);
+/*
+ * Used to synchronize access to the list of trusted keys (ima_trusted_keys)
+ * that need to be measured when IMA is initialized.
+ */
+static DEFINE_MUTEX(ima_trusted_keys_mutex);
+static LIST_HEAD(ima_trusted_keys);
+
/* lookup up the digest value in the hash table, and return the entry */
static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value,
int pcr)
@@ -232,3 +239,90 @@ int __init ima_init_digests(void)
return 0;
}
+
+static void ima_free_trusted_key_entry(struct ima_trusted_key_entry *entry)
+{
+ if (entry != NULL) {
+ if (entry->public_key != NULL)
+ kzfree(entry->public_key);
+ if (entry->key_description != NULL)
+ kzfree(entry->key_description);
+ kzfree(entry);
+ }
+}
+
+static struct ima_trusted_key_entry *ima_alloc_trusted_queue_entry(
+ struct key *key,
+ enum ima_hooks func)
+{
+ int rc = 0;
+ const struct public_key *pk;
+ size_t key_description_len;
+ struct ima_trusted_key_entry *entry = NULL;
+
+ pk = key->payload.data[asym_crypto];
+ key_description_len = strlen(key->description) + 1;
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (entry != NULL) {
+ entry->public_key = kzalloc(pk->keylen, GFP_KERNEL);
+ entry->key_description =
+ kzalloc(key_description_len, GFP_KERNEL);
+ }
+
+ if ((entry == NULL) || (entry->public_key == NULL) ||
+ (entry->key_description == NULL)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ strcpy(entry->key_description, key->description);
+ memcpy(entry->public_key, pk->key, pk->keylen);
+ entry->public_key_len = pk->keylen;
+ entry->func = func;
+ rc = 0;
+
+out:
+ if (rc) {
+ ima_free_trusted_key_entry(entry);
+ entry = NULL;
+ }
+
+ return entry;
+}
+
+int ima_queue_key_for_measurement(struct key *key, enum ima_hooks func)
+{
+ int rc = 0;
+ struct ima_trusted_key_entry *entry = NULL;
+
+ mutex_lock(&ima_trusted_keys_mutex);
+
+ entry = ima_alloc_trusted_queue_entry(key, func);
+ if (entry != NULL) {
+ INIT_LIST_HEAD(&entry->list);
+ list_add_tail(&entry->list, &ima_trusted_keys);
+ } else
+ rc = -ENOMEM;
+
+ mutex_unlock(&ima_trusted_keys_mutex);
+
+ return rc;
+}
+
+void ima_measure_queued_keys(void)
+{
+ struct ima_trusted_key_entry *entry, *tmp;
+
+ mutex_lock(&ima_trusted_keys_mutex);
+
+ list_for_each_entry_safe(entry, tmp, &ima_trusted_keys, list) {
+ process_buffer_measurement(entry->public_key,
+ entry->public_key_len,
+ entry->key_description,
+ NONE, 0);
+ list_del(&entry->list);
+ ima_free_trusted_key_entry(entry);
+ }
+
+ mutex_unlock(&ima_trusted_keys_mutex);
+}
--
2.17.1
