1#ifndef _CRYPTO_LRW_H
2#define _CRYPTO_LRW_H
3
4#include <crypto/b128ops.h>
5
6struct scatterlist;
7struct gf128mul_64k;
8struct blkcipher_desc;
9
10#define LRW_BLOCK_SIZE 16
11
12struct lrw_table_ctx {
13	/* optimizes multiplying a random (non incrementing, as at the
14	 * start of a new sector) value with key2, we could also have
15	 * used 4k optimization tables or no optimization at all. In the
16	 * latter case we would have to store key2 here */
17	struct gf128mul_64k *table;
18	/* stores:
19	 *  key2*{ 0,0,...0,0,0,0,1 }, key2*{ 0,0,...0,0,0,1,1 },
20	 *  key2*{ 0,0,...0,0,1,1,1 }, key2*{ 0,0,...0,1,1,1,1 }
21	 *  key2*{ 0,0,...1,1,1,1,1 }, etc
22	 * needed for optimized multiplication of incrementing values
23	 * with key2 */
24	be128 mulinc[128];
25};
26
27int lrw_init_table(struct lrw_table_ctx *ctx, const u8 *tweak);
28void lrw_free_table(struct lrw_table_ctx *ctx);
29
30struct lrw_crypt_req {
31	be128 *tbuf;
32	unsigned int tbuflen;
33
34	struct lrw_table_ctx *table_ctx;
35	void *crypt_ctx;
36	void (*crypt_fn)(void *ctx, u8 *blks, unsigned int nbytes);
37};
38
39int lrw_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
40	      struct scatterlist *src, unsigned int nbytes,
41	      struct lrw_crypt_req *req);
42
43#endif  /* _CRYPTO_LRW_H */
44