diff options
| -rw-r--r-- | fs/ecryptfs/crypto.c | 106 |
1 files changed, 20 insertions, 86 deletions
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 35b409bda841..fb54a0182f2e 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -37,6 +37,9 @@ #include <asm/unaligned.h> #include "ecryptfs_kernel.h" +#define DECRYPT 0 +#define ENCRYPT 1 + static int ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, struct page *dst_page, struct page *src_page, @@ -334,19 +337,20 @@ static void extent_crypt_complete(struct crypto_async_request *req, int rc) } /** - * encrypt_scatterlist + * crypt_scatterlist * @crypt_stat: Pointer to the crypt_stat struct to initialize. - * @dest_sg: Destination of encrypted data - * @src_sg: Data to be encrypted - * @size: Length of data to be encrypted - * @iv: iv to use during encryption + * @dest_sg: Destination of the data after performing the crypto operation + * @src_sg: Data to be encrypted or decrypted + * @size: Length of data + * @iv: IV to use + * @op: ENCRYPT or DECRYPT to indicate the desired operation * - * Returns the number of bytes encrypted; negative value on error + * Returns the number of bytes encrypted or decrypted; negative value on error */ -static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, - struct scatterlist *dest_sg, - struct scatterlist *src_sg, int size, - unsigned char *iv) +static int crypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, + struct scatterlist *dest_sg, + struct scatterlist *src_sg, int size, + unsigned char *iv, int op) { struct ablkcipher_request *req = NULL; struct extent_crypt_result ecr; @@ -389,9 +393,9 @@ static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, crypt_stat->flags |= ECRYPTFS_KEY_SET; } mutex_unlock(&crypt_stat->cs_tfm_mutex); - ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes.\n", size); ablkcipher_request_set_crypt(req, src_sg, dest_sg, size, iv); - rc = crypto_ablkcipher_encrypt(req); + rc = op == ENCRYPT ? crypto_ablkcipher_encrypt(req) : + crypto_ablkcipher_decrypt(req); if (rc == -EINPROGRESS || rc == -EBUSY) { struct extent_crypt_result *ecr = req->base.data; @@ -624,78 +628,6 @@ out: } /** - * decrypt_scatterlist - * @crypt_stat: Cryptographic context - * @dest_sg: The destination scatterlist to decrypt into - * @src_sg: The source scatterlist to decrypt from - * @size: The number of bytes to decrypt - * @iv: The initialization vector to use for the decryption - * - * Returns the number of bytes decrypted; negative value on error - */ -static int decrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, - struct scatterlist *dest_sg, - struct scatterlist *src_sg, int size, - unsigned char *iv) -{ - struct ablkcipher_request *req = NULL; - struct extent_crypt_result ecr; - int rc = 0; - - BUG_ON(!crypt_stat || !crypt_stat->tfm - || !(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)); - if (unlikely(ecryptfs_verbosity > 0)) { - ecryptfs_printk(KERN_DEBUG, "Key size [%zd]; key:\n", - crypt_stat->key_size); - ecryptfs_dump_hex(crypt_stat->key, - crypt_stat->key_size); - } - - init_completion(&ecr.completion); - - mutex_lock(&crypt_stat->cs_tfm_mutex); - req = ablkcipher_request_alloc(crypt_stat->tfm, GFP_NOFS); - if (!req) { - mutex_unlock(&crypt_stat->cs_tfm_mutex); - rc = -ENOMEM; - goto out; - } - - ablkcipher_request_set_callback(req, - CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, - extent_crypt_complete, &ecr); - /* Consider doing this once, when the file is opened */ - if (!(crypt_stat->flags & ECRYPTFS_KEY_SET)) { - rc = crypto_ablkcipher_setkey(crypt_stat->tfm, crypt_stat->key, - crypt_stat->key_size); - if (rc) { - ecryptfs_printk(KERN_ERR, - "Error setting key; rc = [%d]\n", - rc); - mutex_unlock(&crypt_stat->cs_tfm_mutex); - rc = -EINVAL; - goto out; - } - crypt_stat->flags |= ECRYPTFS_KEY_SET; - } - mutex_unlock(&crypt_stat->cs_tfm_mutex); - ecryptfs_printk(KERN_DEBUG, "Decrypting [%d] bytes.\n", size); - ablkcipher_request_set_crypt(req, src_sg, dest_sg, size, iv); - rc = crypto_ablkcipher_decrypt(req); - if (rc == -EINPROGRESS || rc == -EBUSY) { - struct extent_crypt_result *ecr = req->base.data; - - wait_for_completion(&ecr->completion); - rc = ecr->rc; - INIT_COMPLETION(ecr->completion); - } -out: - ablkcipher_request_free(req); - return rc; - -} - -/** * ecryptfs_encrypt_page_offset * @crypt_stat: The cryptographic context * @dst_page: The page to encrypt into @@ -718,7 +650,8 @@ ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, sg_set_page(&src_sg, src_page, size, offset); sg_set_page(&dst_sg, dst_page, size, offset); - return encrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv); + return crypt_scatterlist(crypt_stat, &dst_sg, &src_sg, + size, iv, ENCRYPT); } /** @@ -745,7 +678,8 @@ ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, sg_init_table(&dst_sg, 1); sg_set_page(&dst_sg, dst_page, size, offset); - return decrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv); + return crypt_scatterlist(crypt_stat, &dst_sg, &src_sg, + size, iv, DECRYPT); } #define ECRYPTFS_MAX_SCATTERLIST_LEN 4 |