lrw.h
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#ifndef _CRYPTO_LRW_H
#define _CRYPTO_LRW_H
#include <crypto/b128ops.h>
struct scatterlist;
struct gf128mul_64k;
struct blkcipher_desc;
#define LRW_BLOCK_SIZE 16
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
* latter case we would have to store key2 here */
struct gf128mul_64k *table;
/* stores:
* key2*{ 0,0,...0,0,0,0,1 }, key2*{ 0,0,...0,0,0,1,1 },
* key2*{ 0,0,...0,0,1,1,1 }, key2*{ 0,0,...0,1,1,1,1 }
* key2*{ 0,0,...1,1,1,1,1 }, etc
* needed for optimized multiplication of incrementing values
* with key2 */
be128 mulinc[128];
};
int lrw_init_table(struct lrw_table_ctx *ctx, const u8 *tweak);
void lrw_free_table(struct lrw_table_ctx *ctx);
struct lrw_crypt_req {
be128 *tbuf;
unsigned int tbuflen;
struct lrw_table_ctx *table_ctx;
void *crypt_ctx;
void (*crypt_fn)(void *ctx, u8 *blks, unsigned int nbytes);
};
int lrw_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes,
struct lrw_crypt_req *req);
#endif /* _CRYPTO_LRW_H */