7 files changed, 129 insertions, 63 deletions

diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index 2d1bb8af7696..9e1e005c7596 100644
--- a/security/keys/encrypted-keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -773,8 +773,8 @@ static int encrypted_init(struct encrypted_key_payload *epayload,
  *
  * On success, return 0. Otherwise return errno.
  */
-static int encrypted_instantiate(struct key *key, const void *data,
-                                 size_t datalen)
+static int encrypted_instantiate(struct key *key,
+                                 struct key_preparsed_payload *prep)
 {
         struct encrypted_key_payload *epayload = NULL;
         char *datablob = NULL;
@@ -782,16 +782,17 @@ static int encrypted_instantiate(struct key *key, const void *data,
         char *master_desc = NULL;
         char *decrypted_datalen = NULL;
         char *hex_encoded_iv = NULL;
+        size_t datalen = prep->datalen;
         int ret;
 
-        if (datalen <= 0 || datalen > 32767 || !data)
+        if (datalen <= 0 || datalen > 32767 || !prep->data)
                 return -EINVAL;
 
         datablob = kmalloc(datalen + 1, GFP_KERNEL);
         if (!datablob)
                 return -ENOMEM;
         datablob[datalen] = 0;
-        memcpy(datablob, data, datalen);
+        memcpy(datablob, prep->data, datalen);
         ret = datablob_parse(datablob, &format, &master_desc,
                              &decrypted_datalen, &hex_encoded_iv);
         if (ret < 0)
@@ -834,16 +835,17 @@ static void encrypted_rcu_free(struct rcu_head *rcu)
  *
  * On success, return 0. Otherwise return errno.
  */
-static int encrypted_update(struct key *key, const void *data, size_t datalen)
+static int encrypted_update(struct key *key, struct key_preparsed_payload *prep)
 {
         struct encrypted_key_payload *epayload = key->payload.data;
         struct encrypted_key_payload *new_epayload;
         char *buf;
         char *new_master_desc = NULL;
         const char *format = NULL;
+        size_t datalen = prep->datalen;
         int ret = 0;
 
-        if (datalen <= 0 || datalen > 32767 || !data)
+        if (datalen <= 0 || datalen > 32767 || !prep->data)
                 return -EINVAL;
 
         buf = kmalloc(datalen + 1, GFP_KERNEL);
@@ -851,7 +853,7 @@ static int encrypted_update(struct key *key, const void *data, size_t datalen)
                 return -ENOMEM;
 
         buf[datalen] = 0;
-        memcpy(buf, data, datalen);
+        memcpy(buf, prep->data, datalen);
         ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL);
         if (ret < 0)
                 goto out;
diff --git a/security/keys/key.c b/security/keys/key.c
index 50d96d4e06f2..1d039af99f50 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);
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 3364fbf46807..505d40be196c 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -46,6 +46,9 @@ static int key_get_type_from_user(char *type,
  * Extract the description of a new key from userspace and either add it as a
  * new key to the specified keyring or update a matching key in that keyring.
  *
+ * If the description is NULL or an empty string, the key type is asked to
+ * generate one from the payload.
+ *
  * The keyring must be writable so that we can attach the key to it.
  *
  * If successful, the new key's serial number is returned, otherwise an error
@@ -72,10 +75,17 @@ SYSCALL_DEFINE5(add_key, const char __user *, _type,
         if (ret < 0)
                 goto error;
 
-        description = strndup_user(_description, PAGE_SIZE);
-        if (IS_ERR(description)) {
-                ret = PTR_ERR(description);
-                goto error;
+        description = NULL;
+        if (_description) {
+                description = strndup_user(_description, PAGE_SIZE);
+                if (IS_ERR(description)) {
+                        ret = PTR_ERR(description);
+                        goto error;
+                }
+                if (!*description) {
+                        kfree(description);
+                        description = NULL;
+                }
         }
 
         /* pull the payload in if one was supplied */
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 81e7852d281d..f04d8cf81f3c 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -66,7 +66,7 @@ static inline unsigned keyring_hash(const char *desc)
  * operations.
  */
 static int keyring_instantiate(struct key *keyring,
-                               const void *data, size_t datalen);
+                               struct key_preparsed_payload *prep);
 static int keyring_match(const struct key *keyring, const void *criterion);
 static void keyring_revoke(struct key *keyring);
 static void keyring_destroy(struct key *keyring);
@@ -121,12 +121,12 @@ static void keyring_publish_name(struct key *keyring)
  * Returns 0 on success, -EINVAL if given any data.
  */
 static int keyring_instantiate(struct key *keyring,
-                               const void *data, size_t datalen)
+                               struct key_preparsed_payload *prep)
 {
         int ret;
 
         ret = -EINVAL;
-        if (datalen == 0) {
+        if (prep->datalen == 0) {
                 /* make the keyring available by name if it has one */
                 keyring_publish_name(keyring);
                 ret = 0;
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index 60d4e3f5e4bb..85730d5a5a59 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -19,7 +19,8 @@
 #include <asm/uaccess.h>
 #include "internal.h"
 
-static int request_key_auth_instantiate(struct key *, const void *, size_t);
+static int request_key_auth_instantiate(struct key *,
+                                        struct key_preparsed_payload *);
 static void request_key_auth_describe(const struct key *, struct seq_file *);
 static void request_key_auth_revoke(struct key *);
 static void request_key_auth_destroy(struct key *);
@@ -42,10 +43,9 @@ struct key_type key_type_request_key_auth = {
  * Instantiate a request-key authorisation key.
  */
 static int request_key_auth_instantiate(struct key *key,
-                                        const void *data,
-                                        size_t datalen)
+                                        struct key_preparsed_payload *prep)
 {
-        key->payload.data = (struct request_key_auth *) data;
+        key->payload.data = (struct request_key_auth *)prep->data;
         return 0;
 }
 
diff --git a/security/keys/trusted.c b/security/keys/trusted.c
index 2d5d041f2049..42036c7a0856 100644
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c
@@ -927,22 +927,23 @@ static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
  *
  * On success, return 0. Otherwise return errno.
  */
-static int trusted_instantiate(struct key *key, const void *data,
-                               size_t datalen)
+static int trusted_instantiate(struct key *key,
+                               struct key_preparsed_payload *prep)
 {
         struct trusted_key_payload *payload = NULL;
         struct trusted_key_options *options = NULL;
+        size_t datalen = prep->datalen;
         char *datablob;
         int ret = 0;
         int key_cmd;
 
-        if (datalen <= 0 || datalen > 32767 || !data)
+        if (datalen <= 0 || datalen > 32767 || !prep->data)
                 return -EINVAL;
 
         datablob = kmalloc(datalen + 1, GFP_KERNEL);
         if (!datablob)
                 return -ENOMEM;
-        memcpy(datablob, data, datalen);
+        memcpy(datablob, prep->data, datalen);
         datablob[datalen] = '\0';
 
         options = trusted_options_alloc();
@@ -1011,17 +1012,18 @@ static void trusted_rcu_free(struct rcu_head *rcu)
 /*
  * trusted_update - reseal an existing key with new PCR values
  */
-static int trusted_update(struct key *key, const void *data, size_t datalen)
+static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
 {
         struct trusted_key_payload *p = key->payload.data;
         struct trusted_key_payload *new_p;
         struct trusted_key_options *new_o;
+        size_t datalen = prep->datalen;
         char *datablob;
         int ret = 0;
 
         if (!p->migratable)
                 return -EPERM;
-        if (datalen <= 0 || datalen > 32767 || !data)
+        if (datalen <= 0 || datalen > 32767 || !prep->data)
                 return -EINVAL;
 
         datablob = kmalloc(datalen + 1, GFP_KERNEL);
@@ -1038,7 +1040,7 @@ static int trusted_update(struct key *key, const void *data, size_t datalen)
                 goto out;
         }
 
-        memcpy(datablob, data, datalen);
+        memcpy(datablob, prep->data, datalen);
         datablob[datalen] = '\0';
         ret = datablob_parse(datablob, new_p, new_o);
         if (ret != Opt_update) {
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
index c7660a25a3e4..55dc88939185 100644
--- a/security/keys/user_defined.c
+++ b/security/keys/user_defined.c
@@ -58,13 +58,14 @@ EXPORT_SYMBOL_GPL(key_type_logon);
 /*
  * instantiate a user defined key
  */
-int user_instantiate(struct key *key, const void *data, size_t datalen)
+int user_instantiate(struct key *key, struct key_preparsed_payload *prep)
 {
         struct user_key_payload *upayload;
+        size_t datalen = prep->datalen;
         int ret;
 
         ret = -EINVAL;
-        if (datalen <= 0 || datalen > 32767 || !data)
+        if (datalen <= 0 || datalen > 32767 || !prep->data)
                 goto error;
 
         ret = key_payload_reserve(key, datalen);
@@ -78,7 +79,7 @@ int user_instantiate(struct key *key, const void *data, size_t datalen)
 
         /* attach the data */
         upayload->datalen = datalen;
-        memcpy(upayload->data, data, datalen);
+        memcpy(upayload->data, prep->data, datalen);
         rcu_assign_keypointer(key, upayload);
         ret = 0;
 
@@ -92,13 +93,14 @@ EXPORT_SYMBOL_GPL(user_instantiate);
  * update a user defined key
  * - the key's semaphore is write-locked
  */
-int user_update(struct key *key, const void *data, size_t datalen)
+int user_update(struct key *key, struct key_preparsed_payload *prep)
 {
         struct user_key_payload *upayload, *zap;
+        size_t datalen = prep->datalen;
         int ret;
 
         ret = -EINVAL;
-        if (datalen <= 0 || datalen > 32767 || !data)
+        if (datalen <= 0 || datalen > 32767 || !prep->data)
                 goto error;
 
         /* construct a replacement payload */
@@ -108,7 +110,7 @@ int user_update(struct key *key, const void *data, size_t datalen)
                 goto error;
 
         upayload->datalen = datalen;
-        memcpy(upayload->data, data, datalen);
+        memcpy(upayload->data, prep->data, datalen);
 
         /* check the quota and attach the new data */
         zap = upayload;