crypto: lrw - split gf128mul table initialization from setkey

Split gf128mul initialization from setkey so that it can be used outside
lrw-module.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Jussi Kivilinna 2011-10-18 13:32:24 +03:00 committed by Herbert Xu
parent 4660720df6
commit 171c02048f

View File

@ -29,8 +29,7 @@
#define LRW_BLOCK_SIZE 16
struct priv {
struct crypto_cipher *child;
struct lrw_table_ctx {
/* optimizes multiplying a random (non incrementing, as at the
* start of a new sector) value with key2, we could also have
* used 4k optimization tables or no optimization at all. In the
@ -45,6 +44,11 @@ struct priv {
be128 mulinc[128];
};
struct priv {
struct crypto_cipher *child;
struct lrw_table_ctx table;
};
static inline void setbit128_bbe(void *b, int bit)
{
__set_bit(bit ^ (0x80 -
@ -56,28 +60,16 @@ static inline void setbit128_bbe(void *b, int bit)
), b);
}
static int setkey(struct crypto_tfm *parent, const u8 *key,
unsigned int keylen)
static int lrw_init_table(struct lrw_table_ctx *ctx, const u8 *tweak)
{
struct priv *ctx = crypto_tfm_ctx(parent);
struct crypto_cipher *child = ctx->child;
int err, i;
be128 tmp = { 0 };
int bsize = LRW_BLOCK_SIZE;
crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
if ((err = crypto_cipher_setkey(child, key, keylen - bsize)))
return err;
crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
CRYPTO_TFM_RES_MASK);
int i;
if (ctx->table)
gf128mul_free_64k(ctx->table);
/* initialize multiplication table for Key2 */
ctx->table = gf128mul_init_64k_bbe((be128 *)(key + keylen - bsize));
ctx->table = gf128mul_init_64k_bbe((be128 *)tweak);
if (!ctx->table)
return -ENOMEM;
@ -91,6 +83,32 @@ static int setkey(struct crypto_tfm *parent, const u8 *key,
return 0;
}
static void lrw_free_table(struct lrw_table_ctx *ctx)
{
if (ctx->table)
gf128mul_free_64k(ctx->table);
}
static int setkey(struct crypto_tfm *parent, const u8 *key,
unsigned int keylen)
{
struct priv *ctx = crypto_tfm_ctx(parent);
struct crypto_cipher *child = ctx->child;
int err, bsize = LRW_BLOCK_SIZE;
const u8 *tweak = key + keylen - bsize;
crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
err = crypto_cipher_setkey(child, key, keylen - bsize);
if (err)
return err;
crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
CRYPTO_TFM_RES_MASK);
return lrw_init_table(&ctx->table, tweak);
}
struct sinfo {
be128 t;
struct crypto_tfm *tfm;
@ -157,7 +175,7 @@ static int crypt(struct blkcipher_desc *d,
s.t = *iv;
/* T <- I*Key2 */
gf128mul_64k_bbe(&s.t, ctx->table);
gf128mul_64k_bbe(&s.t, ctx->table.table);
goto first;
@ -165,7 +183,8 @@ static int crypt(struct blkcipher_desc *d,
do {
/* T <- I*Key2, using the optimization
* discussed in the specification */
be128_xor(&s.t, &s.t, &ctx->mulinc[get_index128(iv)]);
be128_xor(&s.t, &s.t,
&ctx->table.mulinc[get_index128(iv)]);
inc(iv);
first:
@ -233,8 +252,8 @@ static int init_tfm(struct crypto_tfm *tfm)
static void exit_tfm(struct crypto_tfm *tfm)
{
struct priv *ctx = crypto_tfm_ctx(tfm);
if (ctx->table)
gf128mul_free_64k(ctx->table);
lrw_free_table(&ctx->table);
crypto_free_cipher(ctx->child);
}