/* LibTomCrypt, modular cryptographic library -- Tom St Denis

 *

 * LibTomCrypt is a library that provides various cryptographic

 * algorithms in a highly modular and flexible manner.

 *

 * The library is free for all purposes without any express

 * guarantee it works.

 */

#include "tomcrypt.h"

/**

  @file sha256.c

  LTC_SHA256 by Tom St Denis

*/

#ifdef LTC_SHA256

const struct ltc_hash_descriptor sha256_desc =

{

    "sha256",

    0,

    32,

    64,

    /* OID */

   { 2, 16, 840, 1, 101, 3, 4, 2, 1,  },

   9,

    &sha256_init,

    &sha256_process,

    &sha256_done,

    &sha256_test,

    NULL

};

#ifdef LTC_SMALL_CODE

/* the K array */

static const ulong32 K[64] = {

    0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL,

    0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL,

    0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL,

    0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,

    0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL,

    0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL,

    0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL,

    0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,

    0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL,

    0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL,

    0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL,

    0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,

    0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL

};

#endif

/* Various logical functions */

#define Ch(x,y,z)       (z ^ (x & (y ^ z)))

#define Maj(x,y,z)      (((x | y) & z) | (x & y))

#define S(x, n)         RORc((x),(n))

#define R(x, n)         (((x)&0xFFFFFFFFUL)>>(n))

#define Sigma0(x)       (S(x, 2) ^ S(x, 13) ^ S(x, 22))

#define Sigma1(x)       (S(x, 6) ^ S(x, 11) ^ S(x, 25))

#define Gamma0(x)       (S(x, 7) ^ S(x, 18) ^ R(x, 3))

#define Gamma1(x)       (S(x, 17) ^ S(x, 19) ^ R(x, 10))

/* compress 512-bits */

#ifdef LTC_CLEAN_STACK

static int _sha256_compress(hash_state * md, unsigned char *buf)

#else

static int  sha256_compress(hash_state * md, unsigned char *buf)

#endif

{

    ulong32 S[8], W[64], t0, t1;

#ifdef LTC_SMALL_CODE

    ulong32 t;

#endif

    int i;

    /* copy state into S */

    for (i = 0; i < 8; i++) {

        S[i] = md->sha256.state[i];

    }

    /* copy the state into 512-bits into W[0..15] */

    for (i = 0; i < 16; i++) {

        LOAD32H(W[i], buf + (4*i));

    }

    /* fill W[16..63] */

    for (i = 16; i < 64; i++) {

        W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];

    }

    /* Compress */

#ifdef LTC_SMALL_CODE

#define RND(a,b,c,d,e,f,g,h,i)                         \

     t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];   \

     t1 = Sigma0(a) + Maj(a, b, c);                    \

     d += t0;                                          \

     h  = t0 + t1;

     for (i = 0; i < 64; ++i) {

         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i);

         t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];

         S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;

     }

#else

#define RND(a,b,c,d,e,f,g,h,i,ki)                    \

     t0 = h + Sigma1(e) + Ch(e, f, g) + ki + W[i];   \

     t1 = Sigma0(a) + Maj(a, b, c);                  \

     d += t0;                                        \

     h  = t0 + t1;

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],0,0x428a2f98);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],1,0x71374491);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],2,0xb5c0fbcf);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],3,0xe9b5dba5);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],4,0x3956c25b);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],5,0x59f111f1);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],6,0x923f82a4);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],7,0xab1c5ed5);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],8,0xd807aa98);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],9,0x12835b01);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],10,0x243185be);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],11,0x550c7dc3);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],12,0x72be5d74);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],13,0x80deb1fe);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],14,0x9bdc06a7);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],15,0xc19bf174);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],16,0xe49b69c1);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],17,0xefbe4786);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],18,0x0fc19dc6);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],19,0x240ca1cc);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],20,0x2de92c6f);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],21,0x4a7484aa);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],22,0x5cb0a9dc);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],23,0x76f988da);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],24,0x983e5152);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],25,0xa831c66d);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],26,0xb00327c8);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],27,0xbf597fc7);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],28,0xc6e00bf3);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],29,0xd5a79147);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],30,0x06ca6351);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],31,0x14292967);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],32,0x27b70a85);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],33,0x2e1b2138);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],34,0x4d2c6dfc);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],35,0x53380d13);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],36,0x650a7354);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],37,0x766a0abb);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],38,0x81c2c92e);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],39,0x92722c85);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],40,0xa2bfe8a1);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],41,0xa81a664b);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],42,0xc24b8b70);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],43,0xc76c51a3);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],44,0xd192e819);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],45,0xd6990624);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],46,0xf40e3585);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],47,0x106aa070);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],48,0x19a4c116);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],49,0x1e376c08);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],50,0x2748774c);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],51,0x34b0bcb5);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],52,0x391c0cb3);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],53,0x4ed8aa4a);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],54,0x5b9cca4f);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],55,0x682e6ff3);

    RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],56,0x748f82ee);

    RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],57,0x78a5636f);

    RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],58,0x84c87814);

    RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],59,0x8cc70208);

    RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],60,0x90befffa);

    RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],61,0xa4506ceb);

    RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],62,0xbef9a3f7);

    RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],63,0xc67178f2);

#undef RND

#endif

    /* feedback */

    for (i = 0; i < 8; i++) {

        md->sha256.state[i] = md->sha256.state[i] + S[i];

    }

    return CRYPT_OK;

}

#ifdef LTC_CLEAN_STACK

static int sha256_compress(hash_state * md, unsigned char *buf)

{

    int err;

    err = _sha256_compress(md, buf);

    burn_stack(sizeof(ulong32) * 74);

    return err;

}

#endif

/**

   Initialize the hash state

   @param md   The hash state you wish to initialize

   @return CRYPT_OK if successful

*/

int sha256_init(hash_state * md)

{

    LTC_ARGCHK(md != NULL);

    md->sha256.curlen = 0;

    md->sha256.length = 0;

    md->sha256.state[0] = 0x6A09E667UL;

    md->sha256.state[1] = 0xBB67AE85UL;

    md->sha256.state[2] = 0x3C6EF372UL;

    md->sha256.state[3] = 0xA54FF53AUL;

    md->sha256.state[4] = 0x510E527FUL;

    md->sha256.state[5] = 0x9B05688CUL;

    md->sha256.state[6] = 0x1F83D9ABUL;

    md->sha256.state[7] = 0x5BE0CD19UL;

    return CRYPT_OK;

}

/**

   Process a block of memory though the hash

   @param md     The hash state

   @param in     The data to hash

   @param inlen  The length of the data (octets)

   @return CRYPT_OK if successful

*/

HASH_PROCESS(sha256_process, sha256_compress, sha256, 64)

/**

   Terminate the hash to get the digest

   @param md  The hash state

   @param out [out] The destination of the hash (32 bytes)

   @return CRYPT_OK if successful

*/

int sha256_done(hash_state * md, unsigned char *out)

{

    int i;

    LTC_ARGCHK(md  != NULL);

    LTC_ARGCHK(out != NULL);

    if (md->sha256.curlen >= sizeof(md->sha256.buf)) {

       return CRYPT_INVALID_ARG;

    }

    /* increase the length of the message */

    md->sha256.length += md->sha256.curlen * 8;

    /* append the '1' bit */

    md->sha256.buf[md->sha256.curlen++] = (unsigned char)0x80;

    /* if the length is currently above 56 bytes we append zeros

     * then compress.  Then we can fall back to padding zeros and length

     * encoding like normal.

     */

    if (md->sha256.curlen > 56) {

        while (md->sha256.curlen < 64) {

            md->sha256.buf[md->sha256.curlen++] = (unsigned char)0;

        }

        sha256_compress(md, md->sha256.buf);

        md->sha256.curlen = 0;

    }

    /* pad upto 56 bytes of zeroes */

    while (md->sha256.curlen < 56) {

        md->sha256.buf[md->sha256.curlen++] = (unsigned char)0;

    }

    /* store length */

    STORE64H(md->sha256.length, md->sha256.buf+56);

    sha256_compress(md, md->sha256.buf);

    /* copy output */

    for (i = 0; i < 8; i++) {

        STORE32H(md->sha256.state[i], out+(4*i));

    }

#ifdef LTC_CLEAN_STACK

    zeromem(md, sizeof(hash_state));

#endif

    return CRYPT_OK;

}

/**

  Self-test the hash

  @return CRYPT_OK if successful, CRYPT_NOP if self-tests have been disabled

*/

int  sha256_test(void)

{

 #ifndef LTC_TEST

    return CRYPT_NOP;

 #else

  static const struct {

      const char *msg;

      unsigned char hash[32];

  } tests[] = {

    { "abc",

      { 0xba, 0x78, 0x16, 0xbf, 0x8f, 0x01, 0xcf, 0xea,

        0x41, 0x41, 0x40, 0xde, 0x5d, 0xae, 0x22, 0x23,

        0xb0, 0x03, 0x61, 0xa3, 0x96, 0x17, 0x7a, 0x9c,

        0xb4, 0x10, 0xff, 0x61, 0xf2, 0x00, 0x15, 0xad }

    },

    { "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",

      { 0x24, 0x8d, 0x6a, 0x61, 0xd2, 0x06, 0x38, 0xb8,

        0xe5, 0xc0, 0x26, 0x93, 0x0c, 0x3e, 0x60, 0x39,

        0xa3, 0x3c, 0xe4, 0x59, 0x64, 0xff, 0x21, 0x67,

        0xf6, 0xec, 0xed, 0xd4, 0x19, 0xdb, 0x06, 0xc1 }

    },

  };

  int i;

  unsigned char tmp[32];

  hash_state md;

  for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) {

      sha256_init(&md);

      sha256_process(&md, (unsigned char*)tests[i].msg, (unsigned long)strlen(tests[i].msg));

      sha256_done(&md, tmp);

      if (compare_testvector(tmp, sizeof(tmp), tests[i].hash, sizeof(tests[i].hash), "SHA256", i)) {

         return CRYPT_FAIL_TESTVECTOR;

      }

  }

  return CRYPT_OK;

 #endif

}

#endif

/* ref:         $Format:%D$ */

/* git commit:  $Format:%H$ */

/* commit time: $Format:%ai$ */