include/crypto/chacha20.h

   1 /*
   2  * Common values for the ChaCha20 algorithm
   3  */
   4
   5 #ifndef _CRYPTO_CHACHA20_H
   6 #define _CRYPTO_CHACHA20_H
   7
   8 #include <linux/types.h>
   9 #include <linux/crypto.h>
  10
  11 #define CHACHA20_IV_SIZE        16
  12 #define CHACHA20_KEY_SIZE       32
  13 #define CHACHA20_BLOCK_SIZE     64
  14
  15 struct chacha20_ctx {
  16         u32 key[8];
  17 };
  18
  19 void chacha20_block(u32 *state, u8 *stream);
  20 void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv);
  21 int crypto_chacha20_setkey(struct crypto_tfm *tfm, const u8 *key,
  22                            unsigned int keysize);
  23 int crypto_chacha20_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
  24                           struct scatterlist *src, unsigned int nbytes);
  25
  26 enum chacha_constants { /* expand 32-byte k */
  27         CHACHA_CONSTANT_EXPA = 0x61707865U,
  28         CHACHA_CONSTANT_ND_3 = 0x3320646eU,
  29         CHACHA_CONSTANT_2_BY = 0x79622d32U,
  30         CHACHA_CONSTANT_TE_K = 0x6b206574U
  31 };
  32
  33 static inline void chacha_init_consts(u32 *state)
  34 {
  35         state[0]  = CHACHA_CONSTANT_EXPA;
  36         state[1]  = CHACHA_CONSTANT_ND_3;
  37         state[2]  = CHACHA_CONSTANT_2_BY;
  38         state[3]  = CHACHA_CONSTANT_TE_K;
  39 }
  40
  41 #endif