[BLOCK] cryptoloop: Use block ciphers where applicable
This patch converts cryptoloop to use the new block cipher type where applicable. As a result the ECB-specific and CBC-specific transfer functions have been merged. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu
Родитель
cba83564d1
Коммит
69affe7fc5
|
|
@ -40,11 +40,13 @@ static int
|
|||
cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info)
|
||||
{
|
||||
int err = -EINVAL;
|
||||
int cipher_len;
|
||||
int mode_len;
|
||||
char cms[LO_NAME_SIZE]; /* cipher-mode string */
|
||||
char *cipher;
|
||||
char *mode;
|
||||
char *cmsp = cms; /* c-m string pointer */
|
||||
struct crypto_tfm *tfm = NULL;
|
||||
struct crypto_blkcipher *tfm;
|
||||
|
||||
/* encryption breaks for non sector aligned offsets */
|
||||
|
||||
|
|
@ -53,20 +55,39 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info)
|
|||
|
||||
strncpy(cms, info->lo_crypt_name, LO_NAME_SIZE);
|
||||
cms[LO_NAME_SIZE - 1] = 0;
|
||||
cipher = strsep(&cmsp, "-");
|
||||
mode = strsep(&cmsp, "-");
|
||||
|
||||
if (mode == NULL || strcmp(mode, "cbc") == 0)
|
||||
tfm = crypto_alloc_tfm(cipher, CRYPTO_TFM_MODE_CBC |
|
||||
CRYPTO_TFM_REQ_MAY_SLEEP);
|
||||
else if (strcmp(mode, "ecb") == 0)
|
||||
tfm = crypto_alloc_tfm(cipher, CRYPTO_TFM_MODE_ECB |
|
||||
CRYPTO_TFM_REQ_MAY_SLEEP);
|
||||
if (tfm == NULL)
|
||||
cipher = cmsp;
|
||||
cipher_len = strcspn(cmsp, "-");
|
||||
|
||||
mode = cmsp + cipher_len;
|
||||
mode_len = 0;
|
||||
if (*mode) {
|
||||
mode++;
|
||||
mode_len = strcspn(mode, "-");
|
||||
}
|
||||
|
||||
if (!mode_len) {
|
||||
mode = "cbc";
|
||||
mode_len = 3;
|
||||
}
|
||||
|
||||
if (cipher_len + mode_len + 3 > LO_NAME_SIZE)
|
||||
return -EINVAL;
|
||||
|
||||
err = tfm->crt_u.cipher.cit_setkey(tfm, info->lo_encrypt_key,
|
||||
info->lo_encrypt_key_size);
|
||||
memmove(cms, mode, mode_len);
|
||||
cmsp = cms + mode_len;
|
||||
*cmsp++ = '(';
|
||||
memcpy(cmsp, info->lo_crypt_name, cipher_len);
|
||||
cmsp += cipher_len;
|
||||
*cmsp++ = ')';
|
||||
*cmsp = 0;
|
||||
|
||||
tfm = crypto_alloc_blkcipher(cms, 0, CRYPTO_ALG_ASYNC);
|
||||
if (IS_ERR(tfm))
|
||||
return PTR_ERR(tfm);
|
||||
|
||||
err = crypto_blkcipher_setkey(tfm, info->lo_encrypt_key,
|
||||
info->lo_encrypt_key_size);
|
||||
|
||||
if (err != 0)
|
||||
goto out_free_tfm;
|
||||
|
|
@ -75,99 +96,49 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info)
|
|||
return 0;
|
||||
|
||||
out_free_tfm:
|
||||
crypto_free_tfm(tfm);
|
||||
crypto_free_blkcipher(tfm);
|
||||
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
|
||||
typedef int (*encdec_ecb_t)(struct crypto_tfm *tfm,
|
||||
typedef int (*encdec_cbc_t)(struct blkcipher_desc *desc,
|
||||
struct scatterlist *sg_out,
|
||||
struct scatterlist *sg_in,
|
||||
unsigned int nsg);
|
||||
|
||||
|
||||
static int
|
||||
cryptoloop_transfer_ecb(struct loop_device *lo, int cmd,
|
||||
struct page *raw_page, unsigned raw_off,
|
||||
struct page *loop_page, unsigned loop_off,
|
||||
int size, sector_t IV)
|
||||
cryptoloop_transfer(struct loop_device *lo, int cmd,
|
||||
struct page *raw_page, unsigned raw_off,
|
||||
struct page *loop_page, unsigned loop_off,
|
||||
int size, sector_t IV)
|
||||
{
|
||||
struct crypto_tfm *tfm = (struct crypto_tfm *) lo->key_data;
|
||||
struct scatterlist sg_out = { NULL, };
|
||||
struct scatterlist sg_in = { NULL, };
|
||||
|
||||
encdec_ecb_t encdecfunc;
|
||||
struct page *in_page, *out_page;
|
||||
unsigned in_offs, out_offs;
|
||||
|
||||
if (cmd == READ) {
|
||||
in_page = raw_page;
|
||||
in_offs = raw_off;
|
||||
out_page = loop_page;
|
||||
out_offs = loop_off;
|
||||
encdecfunc = tfm->crt_u.cipher.cit_decrypt;
|
||||
} else {
|
||||
in_page = loop_page;
|
||||
in_offs = loop_off;
|
||||
out_page = raw_page;
|
||||
out_offs = raw_off;
|
||||
encdecfunc = tfm->crt_u.cipher.cit_encrypt;
|
||||
}
|
||||
|
||||
while (size > 0) {
|
||||
const int sz = min(size, LOOP_IV_SECTOR_SIZE);
|
||||
|
||||
sg_in.page = in_page;
|
||||
sg_in.offset = in_offs;
|
||||
sg_in.length = sz;
|
||||
|
||||
sg_out.page = out_page;
|
||||
sg_out.offset = out_offs;
|
||||
sg_out.length = sz;
|
||||
|
||||
encdecfunc(tfm, &sg_out, &sg_in, sz);
|
||||
|
||||
size -= sz;
|
||||
in_offs += sz;
|
||||
out_offs += sz;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
typedef int (*encdec_cbc_t)(struct crypto_tfm *tfm,
|
||||
struct scatterlist *sg_out,
|
||||
struct scatterlist *sg_in,
|
||||
unsigned int nsg, u8 *iv);
|
||||
|
||||
static int
|
||||
cryptoloop_transfer_cbc(struct loop_device *lo, int cmd,
|
||||
struct page *raw_page, unsigned raw_off,
|
||||
struct page *loop_page, unsigned loop_off,
|
||||
int size, sector_t IV)
|
||||
{
|
||||
struct crypto_tfm *tfm = (struct crypto_tfm *) lo->key_data;
|
||||
struct crypto_blkcipher *tfm = lo->key_data;
|
||||
struct blkcipher_desc desc = {
|
||||
.tfm = tfm,
|
||||
.flags = CRYPTO_TFM_REQ_MAY_SLEEP,
|
||||
};
|
||||
struct scatterlist sg_out = { NULL, };
|
||||
struct scatterlist sg_in = { NULL, };
|
||||
|
||||
encdec_cbc_t encdecfunc;
|
||||
struct page *in_page, *out_page;
|
||||
unsigned in_offs, out_offs;
|
||||
int err;
|
||||
|
||||
if (cmd == READ) {
|
||||
in_page = raw_page;
|
||||
in_offs = raw_off;
|
||||
out_page = loop_page;
|
||||
out_offs = loop_off;
|
||||
encdecfunc = tfm->crt_u.cipher.cit_decrypt_iv;
|
||||
encdecfunc = crypto_blkcipher_crt(tfm)->decrypt;
|
||||
} else {
|
||||
in_page = loop_page;
|
||||
in_offs = loop_off;
|
||||
out_page = raw_page;
|
||||
out_offs = raw_off;
|
||||
encdecfunc = tfm->crt_u.cipher.cit_encrypt_iv;
|
||||
encdecfunc = crypto_blkcipher_crt(tfm)->encrypt;
|
||||
}
|
||||
|
||||
while (size > 0) {
|
||||
|
|
@ -183,7 +154,10 @@ cryptoloop_transfer_cbc(struct loop_device *lo, int cmd,
|
|||
sg_out.offset = out_offs;
|
||||
sg_out.length = sz;
|
||||
|
||||
encdecfunc(tfm, &sg_out, &sg_in, sz, (u8 *)iv);
|
||||
desc.info = iv;
|
||||
err = encdecfunc(&desc, &sg_out, &sg_in, sz);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
IV++;
|
||||
size -= sz;
|
||||
|
|
@ -194,32 +168,6 @@ cryptoloop_transfer_cbc(struct loop_device *lo, int cmd,
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int
|
||||
cryptoloop_transfer(struct loop_device *lo, int cmd,
|
||||
struct page *raw_page, unsigned raw_off,
|
||||
struct page *loop_page, unsigned loop_off,
|
||||
int size, sector_t IV)
|
||||
{
|
||||
struct crypto_tfm *tfm = (struct crypto_tfm *) lo->key_data;
|
||||
if(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB)
|
||||
{
|
||||
lo->transfer = cryptoloop_transfer_ecb;
|
||||
return cryptoloop_transfer_ecb(lo, cmd, raw_page, raw_off,
|
||||
loop_page, loop_off, size, IV);
|
||||
}
|
||||
if(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_CBC)
|
||||
{
|
||||
lo->transfer = cryptoloop_transfer_cbc;
|
||||
return cryptoloop_transfer_cbc(lo, cmd, raw_page, raw_off,
|
||||
loop_page, loop_off, size, IV);
|
||||
}
|
||||
|
||||
/* This is not supposed to happen */
|
||||
|
||||
printk( KERN_ERR "cryptoloop: unsupported cipher mode in cryptoloop_transfer!\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int
|
||||
cryptoloop_ioctl(struct loop_device *lo, int cmd, unsigned long arg)
|
||||
{
|
||||
|
|
@ -229,9 +177,9 @@ cryptoloop_ioctl(struct loop_device *lo, int cmd, unsigned long arg)
|
|||
static int
|
||||
cryptoloop_release(struct loop_device *lo)
|
||||
{
|
||||
struct crypto_tfm *tfm = (struct crypto_tfm *) lo->key_data;
|
||||
struct crypto_blkcipher *tfm = lo->key_data;
|
||||
if (tfm != NULL) {
|
||||
crypto_free_tfm(tfm);
|
||||
crypto_free_blkcipher(tfm);
|
||||
lo->key_data = NULL;
|
||||
return 0;
|
||||
}
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче