diff options
| -rw-r--r-- | crypto/lrw.c | 61 |
1 files changed, 40 insertions, 21 deletions
diff --git a/crypto/lrw.c b/crypto/lrw.c index bee60226f72..91c17fa1837 100644 --- a/crypto/lrw.c +++ b/crypto/lrw.c @@ -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); } |