1 files changed, 82 insertions, 32 deletions

diff --git a/security/keys/key.c b/security/keys/key.c
index 50d96d4..1d039af 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -412,8 +412,7 @@ EXPORT_SYMBOL(key_payload_reserve);
  * key_construction_mutex.
  */
 static int __key_instantiate_and_link(struct key *key,
-				      const void *data,
-				      size_t datalen,
+				      struct key_preparsed_payload *prep,
 				      struct key *keyring,
 				      struct key *authkey,
 				      unsigned long *_prealloc)
@@ -431,7 +430,7 @@ static int __key_instantiate_and_link(struct key *key,
 	/* can't instantiate twice */
 	if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
 		/* instantiate the key */
-		ret = key->type->instantiate(key, data, datalen);
+		ret = key->type->instantiate(key, prep);
 
 		if (ret == 0) {
 			/* mark the key as being instantiated */
@@ -482,22 +481,37 @@ int key_instantiate_and_link(struct key *key,
 			     struct key *keyring,
 			     struct key *authkey)
 {
+	struct key_preparsed_payload prep;
 	unsigned long prealloc;
 	int ret;
 
+	memset(&prep, 0, sizeof(prep));
+	prep.data = data;
+	prep.datalen = datalen;
+	prep.quotalen = key->type->def_datalen;
+	if (key->type->preparse) {
+		ret = key->type->preparse(&prep);
+		if (ret < 0)
+			goto error;
+	}
+
 	if (keyring) {
 		ret = __key_link_begin(keyring, key->type, key->description,
 				       &prealloc);
 		if (ret < 0)
-			return ret;
+			goto error_free_preparse;
 	}
 
-	ret = __key_instantiate_and_link(key, data, datalen, keyring, authkey,
+	ret = __key_instantiate_and_link(key, &prep, keyring, authkey,
 					 &prealloc);
 
 	if (keyring)
 		__key_link_end(keyring, key->type, prealloc);
 
+error_free_preparse:
+	if (key->type->preparse)
+		key->type->free_preparse(&prep);
+error:
 	return ret;
 }
 
@@ -706,7 +720,7 @@ void key_type_put(struct key_type *ktype)
  * if we get an error.
  */
 static inline key_ref_t __key_update(key_ref_t key_ref,
-				     const void *payload, size_t plen)
+				     struct key_preparsed_payload *prep)
 {
 	struct key *key = key_ref_to_ptr(key_ref);
 	int ret;
@@ -722,7 +736,7 @@ static inline key_ref_t __key_update(key_ref_t key_ref,
 
 	down_write(&key->sem);
 
-	ret = key->type->update(key, payload, plen);
+	ret = key->type->update(key, prep);
 	if (ret == 0)
 		/* updating a negative key instantiates it */
 		clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
@@ -774,6 +788,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 			       unsigned long flags)
 {
 	unsigned long prealloc;
+	struct key_preparsed_payload prep;
 	const struct cred *cred = current_cred();
 	struct key_type *ktype;
 	struct key *keyring, *key = NULL;
@@ -789,8 +804,9 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	}
 
 	key_ref = ERR_PTR(-EINVAL);
-	if (!ktype->match || !ktype->instantiate)
-		goto error_2;
+	if (!ktype->match || !ktype->instantiate ||
+	    (!description && !ktype->preparse))
+		goto error_put_type;
 
 	keyring = key_ref_to_ptr(keyring_ref);
 
@@ -798,18 +814,37 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 
 	key_ref = ERR_PTR(-ENOTDIR);
 	if (keyring->type != &key_type_keyring)
-		goto error_2;
+		goto error_put_type;
+
+	memset(&prep, 0, sizeof(prep));
+	prep.data = payload;
+	prep.datalen = plen;
+	prep.quotalen = ktype->def_datalen;
+	if (ktype->preparse) {
+		ret = ktype->preparse(&prep);
+		if (ret < 0) {
+			key_ref = ERR_PTR(ret);
+			goto error_put_type;
+		}
+		if (!description)
+			description = prep.description;
+		key_ref = ERR_PTR(-EINVAL);
+		if (!description)
+			goto error_free_prep;
+	}
 
 	ret = __key_link_begin(keyring, ktype, description, &prealloc);
-	if (ret < 0)
-		goto error_2;
+	if (ret < 0) {
+		key_ref = ERR_PTR(ret);
+		goto error_free_prep;
+	}
 
 	/* if we're going to allocate a new key, we're going to have
 	 * to modify the keyring */
 	ret = key_permission(keyring_ref, KEY_WRITE);
 	if (ret < 0) {
 		key_ref = ERR_PTR(ret);
-		goto error_3;
+		goto error_link_end;
 	}
 
 	/* if it's possible to update this type of key, search for an existing
@@ -840,25 +875,27 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 			perm, flags);
 	if (IS_ERR(key)) {
 		key_ref = ERR_CAST(key);
-		goto error_3;
+		goto error_link_end;
 	}
 
 	/* instantiate it and link it into the target keyring */
-	ret = __key_instantiate_and_link(key, payload, plen, keyring, NULL,
-					 &prealloc);
+	ret = __key_instantiate_and_link(key, &prep, keyring, NULL, &prealloc);
 	if (ret < 0) {
 		key_put(key);
 		key_ref = ERR_PTR(ret);
-		goto error_3;
+		goto error_link_end;
 	}
 
 	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
 
- error_3:
+error_link_end:
 	__key_link_end(keyring, ktype, prealloc);
- error_2:
+error_free_prep:
+	if (ktype->preparse)
+		ktype->free_preparse(&prep);
+error_put_type:
 	key_type_put(ktype);
- error:
+error:
 	return key_ref;
 
  found_matching_key:
@@ -866,10 +903,9 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	 * - we can drop the locks first as we have the key pinned
 	 */
 	__key_link_end(keyring, ktype, prealloc);
-	key_type_put(ktype);
 
-	key_ref = __key_update(key_ref, payload, plen);
-	goto error;
+	key_ref = __key_update(key_ref, &prep);
+	goto error_free_prep;
 }
 EXPORT_SYMBOL(key_create_or_update);
 
@@ -888,6 +924,7 @@ EXPORT_SYMBOL(key_create_or_update);
  */
 int key_update(key_ref_t key_ref, const void *payload, size_t plen)
 {
+	struct key_preparsed_payload prep;
 	struct key *key = key_ref_to_ptr(key_ref);
 	int ret;
 
@@ -900,18 +937,31 @@ int key_update(key_ref_t key_ref, const void *payload, size_t plen)
 
 	/* attempt to update it if supported */
 	ret = -EOPNOTSUPP;
-	if (key->type->update) {
-		down_write(&key->sem);
-
-		ret = key->type->update(key, payload, plen);
-		if (ret == 0)
-			/* updating a negative key instantiates it */
-			clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
+	if (!key->type->update)
+		goto error;
 
-		up_write(&key->sem);
+	memset(&prep, 0, sizeof(prep));
+	prep.data = payload;
+	prep.datalen = plen;
+	prep.quotalen = key->type->def_datalen;
+	if (key->type->preparse) {
+		ret = key->type->preparse(&prep);
+		if (ret < 0)
+			goto error;
 	}
 
- error:
+	down_write(&key->sem);
+
+	ret = key->type->update(key, &prep);
+	if (ret == 0)
+		/* updating a negative key instantiates it */
+		clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
+
+	up_write(&key->sem);
+
+	if (key->type->preparse)
+		key->type->free_preparse(&prep);
+error:
 	return ret;
 }
 EXPORT_SYMBOL(key_update);