[PATCH] eCryptfs: Cipher code to new crypto API

Update cipher block encryption code to the new crypto API.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 67 insertions, 34 deletions

diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
index bc706d33559a..c3746f56d162 100644
--- a/fs/ecryptfs/keystore.c
+++ b/fs/ecryptfs/keystore.c
@@ -458,14 +458,16 @@ out:
 static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok,
                                struct ecryptfs_crypt_stat *crypt_stat)
 {
-        int rc = 0;
         struct ecryptfs_password *password_s_ptr;
-        struct crypto_tfm *tfm = NULL;
         struct scatterlist src_sg[2], dst_sg[2];
         struct mutex *tfm_mutex = NULL;
         /* TODO: Use virt_to_scatterlist for these */
         char *encrypted_session_key;
         char *session_key;
+        struct blkcipher_desc desc = {
+                .flags = CRYPTO_TFM_REQ_MAY_SLEEP
+        };
+        int rc = 0;
 
         password_s_ptr = &auth_tok->token.password;
         if (ECRYPTFS_CHECK_FLAG(password_s_ptr->flags,
@@ -482,22 +484,32 @@ static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok,
         if (!strcmp(crypt_stat->cipher,
                     crypt_stat->mount_crypt_stat->global_default_cipher_name)
             && crypt_stat->mount_crypt_stat->global_key_tfm) {
-                tfm = crypt_stat->mount_crypt_stat->global_key_tfm;
+                desc.tfm = crypt_stat->mount_crypt_stat->global_key_tfm;
                 tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex;
         } else {
-                tfm = crypto_alloc_tfm(crypt_stat->cipher,
-                                       CRYPTO_TFM_REQ_WEAK_KEY);
-                if (!tfm) {
-                        printk(KERN_ERR "Error allocating crypto context\n");
-                        rc = -ENOMEM;
+                char *full_alg_name;
+
+                rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name,
+                                                            crypt_stat->cipher,
+                                                            "ecb");
+                if (rc)
+                        goto out;
+                desc.tfm = crypto_alloc_blkcipher(full_alg_name, 0,
+                                                  CRYPTO_ALG_ASYNC);
+                kfree(full_alg_name);
+                if (IS_ERR(desc.tfm)) {
+                        rc = PTR_ERR(desc.tfm);
+                        printk(KERN_ERR "Error allocating crypto context; "
+                               "rc = [%d]\n", rc);
                         goto out;
                 }
+                crypto_blkcipher_set_flags(desc.tfm, CRYPTO_TFM_REQ_WEAK_KEY);
         }
         if (tfm_mutex)
                 mutex_lock(tfm_mutex);
-        rc = crypto_cipher_setkey(tfm,
-                                  password_s_ptr->session_key_encryption_key,
-                                  crypt_stat->key_size);
+        rc = crypto_blkcipher_setkey(desc.tfm,
+                                     password_s_ptr->session_key_encryption_key,
+                                     crypt_stat->key_size);
         if (rc < 0) {
                 printk(KERN_ERR "Error setting key for crypto context\n");
                 rc = -EINVAL;
@@ -528,9 +540,12 @@ static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok,
         auth_tok->session_key.decrypted_key_size =
             auth_tok->session_key.encrypted_key_size;
         dst_sg[0].length = auth_tok->session_key.encrypted_key_size;
-        /* TODO: Handle error condition */
-        crypto_cipher_decrypt(tfm, dst_sg, src_sg,
-                              auth_tok->session_key.encrypted_key_size);
+        rc = crypto_blkcipher_decrypt(&desc, dst_sg, src_sg,
+                                      auth_tok->session_key.encrypted_key_size);
+        if (rc) {
+                printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc);
+                goto out_free_memory;
+        }
         auth_tok->session_key.decrypted_key_size =
             auth_tok->session_key.encrypted_key_size;
         memcpy(auth_tok->session_key.decrypted_key, session_key,
@@ -543,6 +558,7 @@ static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok,
         if (ecryptfs_verbosity > 0)
                 ecryptfs_dump_hex(crypt_stat->key,
                                   crypt_stat->key_size);
+out_free_memory:
         memset(encrypted_session_key, 0, PAGE_CACHE_SIZE);
         free_page((unsigned long)encrypted_session_key);
         memset(session_key, 0, PAGE_CACHE_SIZE);
@@ -551,7 +567,7 @@ out_free_tfm:
         if (tfm_mutex)
                 mutex_unlock(tfm_mutex);
         else
-                crypto_free_tfm(tfm);
+                crypto_free_blkcipher(desc.tfm);
 out:
         return rc;
 }
@@ -800,19 +816,21 @@ write_tag_3_packet(char *dest, size_t max, struct ecryptfs_auth_tok *auth_tok,
                    struct ecryptfs_crypt_stat *crypt_stat,
                    struct ecryptfs_key_record *key_rec, size_t *packet_size)
 {
-        int rc = 0;
-
         size_t i;
         size_t signature_is_valid = 0;
         size_t encrypted_session_key_valid = 0;
         char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
         struct scatterlist dest_sg[2];
         struct scatterlist src_sg[2];
-        struct crypto_tfm *tfm = NULL;
         struct mutex *tfm_mutex = NULL;
         size_t key_rec_size;
         size_t packet_size_length;
         size_t cipher_code;
+        struct blkcipher_desc desc = {
+                .tfm = NULL,
+                .flags = CRYPTO_TFM_REQ_MAY_SLEEP
+        };
+        int rc = 0;
 
         (*packet_size) = 0;
         /* Check for a valid signature on the auth_tok */
@@ -879,33 +897,48 @@ write_tag_3_packet(char *dest, size_t max, struct ecryptfs_auth_tok *auth_tok,
         if (!strcmp(crypt_stat->cipher,
                     crypt_stat->mount_crypt_stat->global_default_cipher_name)
             && crypt_stat->mount_crypt_stat->global_key_tfm) {
-                tfm = crypt_stat->mount_crypt_stat->global_key_tfm;
+                desc.tfm = crypt_stat->mount_crypt_stat->global_key_tfm;
                 tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex;
-        } else
-                tfm = crypto_alloc_tfm(crypt_stat->cipher, 0);
-        if (!tfm) {
-                ecryptfs_printk(KERN_ERR, "Could not initialize crypto "
-                                "context for cipher [%s]\n",
-                                crypt_stat->cipher);
-                rc = -EINVAL;
-                goto out;
+        } else {
+                char *full_alg_name;
+
+                rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name,
+                                                            crypt_stat->cipher,
+                                                            "ecb");
+                if (rc)
+                        goto out;
+                desc.tfm = crypto_alloc_blkcipher(full_alg_name, 0,
+                                                  CRYPTO_ALG_ASYNC);
+                kfree(full_alg_name);
+                if (IS_ERR(desc.tfm)) {
+                        rc = PTR_ERR(desc.tfm);
+                        ecryptfs_printk(KERN_ERR, "Could not initialize crypto "
+                                        "context for cipher [%s]; rc = [%d]\n",
+                                        crypt_stat->cipher, rc);
+                        goto out;
+                }
+                crypto_blkcipher_set_flags(desc.tfm, CRYPTO_TFM_REQ_WEAK_KEY);
         }
         if (tfm_mutex)
                 mutex_lock(tfm_mutex);
-        rc = crypto_cipher_setkey(tfm, session_key_encryption_key,
-                                  crypt_stat->key_size);
+        rc = crypto_blkcipher_setkey(desc.tfm, session_key_encryption_key,
+                                     crypt_stat->key_size);
         if (rc < 0) {
                 if (tfm_mutex)
                         mutex_unlock(tfm_mutex);
                 ecryptfs_printk(KERN_ERR, "Error setting key for crypto "
-                                "context\n");
+                                "context; rc = [%d]\n", rc);
                 goto out;
         }
         rc = 0;
         ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes of the key\n",
                         crypt_stat->key_size);
-        crypto_cipher_encrypt(tfm, dest_sg, src_sg,
-                              (*key_rec).enc_key_size);
+        rc = crypto_blkcipher_encrypt(&desc, dest_sg, src_sg,
+                                      (*key_rec).enc_key_size);
+        if (rc) {
+                printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc);
+                goto out;
+        }
         if (tfm_mutex)
                 mutex_unlock(tfm_mutex);
         ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n");
@@ -968,8 +1001,8 @@ encrypted_session_key_set:
                (*key_rec).enc_key_size);
         (*packet_size) += (*key_rec).enc_key_size;
 out:
-        if (tfm && !tfm_mutex)
-                crypto_free_tfm(tfm);
+        if (desc.tfm && !tfm_mutex)
+                crypto_free_blkcipher(desc.tfm);
         if (rc)
                 (*packet_size) = 0;
         return rc;