eCryptfs: Combine page_offset crypto functions

Combine ecryptfs_encrypt_page_offset() and
ecryptfs_decrypt_page_offset(). These two functions are functionally
identical so they can be safely merged if the caller can indicate
whether an encryption or decryption operation should occur.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
This commit is contained in:
Tyler Hicks 2013-04-05 23:37:51 -07:00
parent 00a699400a
commit a8ca90e207

View File

@ -40,14 +40,9 @@
#define DECRYPT 0
#define ENCRYPT 1
static int
ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
static int crypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
struct page *dst_page, struct page *src_page,
int offset, int size, unsigned char *iv);
static int
ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
struct page *dst_page, struct page *src_page,
int offset, int size, unsigned char *iv);
int offset, int size, unsigned char *iv, int op);
/**
* ecryptfs_to_hex
@ -452,9 +447,9 @@ static int ecryptfs_encrypt_extent(struct page *enc_extent_page,
(unsigned long long)(extent_base + extent_offset), rc);
goto out;
}
rc = ecryptfs_encrypt_page_offset(crypt_stat, enc_extent_page, page,
extent_offset * crypt_stat->extent_size,
crypt_stat->extent_size, extent_iv);
rc = crypt_page_offset(crypt_stat, enc_extent_page, page,
(extent_offset * crypt_stat->extent_size),
crypt_stat->extent_size, extent_iv, ENCRYPT);
if (rc < 0) {
printk(KERN_ERR "%s: Error attempting to encrypt page with "
"page->index = [%ld], extent_offset = [%ld]; "
@ -555,9 +550,9 @@ static int ecryptfs_decrypt_extent(struct page *page,
(unsigned long long)(extent_base + extent_offset), rc);
goto out;
}
rc = ecryptfs_decrypt_page_offset(crypt_stat, page, enc_extent_page,
extent_offset * crypt_stat->extent_size,
crypt_stat->extent_size, extent_iv);
rc = crypt_page_offset(crypt_stat, page, enc_extent_page,
(extent_offset * crypt_stat->extent_size),
crypt_stat->extent_size, extent_iv, DECRYPT);
if (rc < 0) {
printk(KERN_ERR "%s: Error attempting to decrypt to page with "
"page->index = [%ld], extent_offset = [%ld]; "
@ -628,20 +623,20 @@ out:
}
/**
* ecryptfs_encrypt_page_offset
* crypt_page_offset
* @crypt_stat: The cryptographic context
* @dst_page: The page to encrypt into
* @src_page: The page to encrypt from
* @dst_page: The page to write the result into
* @src_page: The page to read from
* @offset: The byte offset into the dst_page and src_page
* @size: The number of bytes to encrypt
* @iv: The initialization vector to use for the encryption
* @size: The number of bytes of data
* @iv: The initialization vector to use for the crypto operation
* @op: ENCRYPT or DECRYPT to indicate the desired operation
*
* Returns the number of bytes encrypted
* Returns the number of bytes encrypted or decrypted
*/
static int
ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
static int crypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
struct page *dst_page, struct page *src_page,
int offset, int size, unsigned char *iv)
int offset, int size, unsigned char *iv, int op)
{
struct scatterlist src_sg, dst_sg;
@ -650,36 +645,8 @@ 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 crypt_scatterlist(crypt_stat, &dst_sg, &src_sg,
size, iv, ENCRYPT);
}
/**
* ecryptfs_decrypt_page_offset
* @crypt_stat: The cryptographic context
* @dst_page: The page to decrypt into
* @src_page: The page to decrypt from
* @offset: The byte offset into the dst_page and src_page
* @size: The number of bytes to decrypt
* @iv: The initialization vector to use for the decryption
*
* Returns the number of bytes decrypted
*/
static int
ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat,
struct page *dst_page, struct page *src_page,
int offset, int size, unsigned char *iv)
{
struct scatterlist src_sg, dst_sg;
sg_init_table(&src_sg, 1);
sg_set_page(&src_sg, src_page, size, offset);
sg_init_table(&dst_sg, 1);
sg_set_page(&dst_sg, dst_page, size, offset);
return crypt_scatterlist(crypt_stat, &dst_sg, &src_sg,
size, iv, DECRYPT);
return crypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv, op);
}
#define ECRYPTFS_MAX_SCATTERLIST_LEN 4