serpent.c

NIST推荐的素域上的椭圆曲线

    a ^= skey->serpent.K[4 * (r) + 0]; \
    b ^= skey->serpent.K[4 * (r) + 1]; \
    c ^= skey->serpent.K[4 * (r) + 2]; \
    d ^= skey->serpent.K[4 * (r) + 3]

#define k_set(r,a,b,c,d)   \
    a = lkey[4 * (r) +  8];  \
    b = lkey[4 * (r) +  9];  \
    c = lkey[4 * (r) + 10];  \
    d = lkey[4 * (r) + 11]

#define k_get(r,a,b,c,d)            \
    skey->serpent.K[4 * (r) + 0] = a; \
    skey->serpent.K[4 * (r) + 1] = b; \
    skey->serpent.K[4 * (r) + 2] = c; \
    skey->serpent.K[4 * (r) + 3] = d

/* the linear transformation and its inverse    */

#define rot(a,b,c,d)    \
    a = ROL(a, 13);    \
    c = ROL(c, 3);     \
    d ^= c ^ (a << 3);  \
    b ^= a ^ c;         \
    d = ROL(d, 7);     \
    b = ROL(b, 1);     \
    a ^= b ^ d;         \
    c ^= d ^ (b << 7);  \
    a = ROL(a, 5);     \
    c = ROL(c, 22)

#define irot(a,b,c,d)   \
    c = ROR(c, 22);    \
    a = ROR(a, 5);     \
    c ^= d ^ (b << 7);  \
    a ^= b ^ d;         \
    d = ROR(d, 7);     \
    b = ROR(b, 1);     \
    d ^= c ^ (a << 3);  \
    b ^= a ^ c;         \
    c = ROR(c, 3);     \
    a = ROR(a, 13)
    
#ifdef CLEAN_STACK
static int _serpent_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
#else
int serpent_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
#endif
{
    unsigned long lkey[140], t, a, b, c, d, e, f, g, h, x;
    unsigned long t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,t11,t12,t13,t14,t15,t16;
    unsigned char buf[32];

    _ARGCHK(key != NULL);
    _ARGCHK(skey != NULL);

    /* check rounds */
    if (num_rounds != 0 && num_rounds != 32) {
       return CRYPT_INVALID_ROUNDS;
    }

    /* check keylen */
    if (keylen < 16 || keylen > 32) {
       return CRYPT_INVALID_KEYSIZE;
    }

    /* copy key and expand to 32bytes as required */
    for (x = 0; x < (unsigned long)keylen; x++) {
        buf[x] = key[x];
    }

    if (x < 32) {
       buf[x++] = 0x01;
       while (x < 32) {
           buf[x++] = 0;
       }
    }

    /* copy key into 32-bit words */
    for (x = 0; x < 8; x++) {
        LOAD32L(lkey[x], &buf[x*4]);
    }

    /* expand using the LFSR to 140 words */
    for (x = 0; x < 132; x++) {
        t = lkey[x] ^ lkey[x+3] ^ lkey[x+5] ^ lkey[x+7] ^ x ^ 0x9E3779B9UL;
        lkey[x + 8] = ROL(t, 11);
    }

    /* perform the substituions */
    for (x = 0; x < 32; ) {
       k_set( x,a,b,c,d);sb3(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb2(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb1(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb0(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb7(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb6(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb5(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
       k_set( x,a,b,c,d);sb4(a,b,c,d,e,f,g,h);k_get( x,e,f,g,h); ++x;
    }
    k_set(32,a,b,c,d);sb3(a,b,c,d,e,f,g,h);k_get(32,e,f,g,h);
    return CRYPT_OK;
}

#ifdef CLEAN_STACK
int serpent_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
{
   int x;
   x = _serpent_setup(key, keylen, num_rounds, skey);
   burn_stack(sizeof(unsigned long)*166 + sizeof(unsigned char)*32);
   return x;
}
#endif

#ifdef CLEAN_STACK
static void _serpent_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey)
#else
void serpent_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey)
#endif
{
    unsigned long a,b,c,d,e,f,g,h;
    unsigned long t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,t11,t12,t13,t14,t15,t16;

    _ARGCHK(pt != NULL);
    _ARGCHK(ct != NULL);
    _ARGCHK(skey != NULL);

    LOAD32L(a, &pt[0]);LOAD32L(b, &pt[4]);LOAD32L(c, &pt[8]);LOAD32L(d, &pt[12]);
    k_xor( 0,a,b,c,d); sb0(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor( 1,e,f,g,h); sb1(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor( 2,a,b,c,d); sb2(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor( 3,e,f,g,h); sb3(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor( 4,a,b,c,d); sb4(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor( 5,e,f,g,h); sb5(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor( 6,a,b,c,d); sb6(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor( 7,e,f,g,h); sb7(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor( 8,a,b,c,d); sb0(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor( 9,e,f,g,h); sb1(e,f,g,h,a,b,c,d); rot(a,b,c,d); 
    k_xor(10,a,b,c,d); sb2(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(11,e,f,g,h); sb3(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(12,a,b,c,d); sb4(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(13,e,f,g,h); sb5(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(14,a,b,c,d); sb6(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(15,e,f,g,h); sb7(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(16,a,b,c,d); sb0(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(17,e,f,g,h); sb1(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(18,a,b,c,d); sb2(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(19,e,f,g,h); sb3(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(20,a,b,c,d); sb4(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(21,e,f,g,h); sb5(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(22,a,b,c,d); sb6(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(23,e,f,g,h); sb7(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(24,a,b,c,d); sb0(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(25,e,f,g,h); sb1(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(26,a,b,c,d); sb2(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(27,e,f,g,h); sb3(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(28,a,b,c,d); sb4(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(29,e,f,g,h); sb5(e,f,g,h,a,b,c,d); rot(a,b,c,d);
    k_xor(30,a,b,c,d); sb6(a,b,c,d,e,f,g,h); rot(e,f,g,h);
    k_xor(31,e,f,g,h); sb7(e,f,g,h,a,b,c,d); k_xor(32,a,b,c,d);
    STORE32L(a, &ct[0]);STORE32L(b, &ct[4]);STORE32L(c, &ct[8]);STORE32L(d, &ct[12]);
}

#ifdef CLEAN_STACK
void serpent_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey)
{
   _serpent_ecb_encrypt(pt, ct, skey);
   burn_stack(sizeof(unsigned long)*24);
}
#endif

#ifdef CLEAN_STACK
static void _serpent_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey)
#else
void serpent_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey)
#endif
{
    unsigned long a,b,c,d,e,f,g,h;
    unsigned long t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,t11,t12,t13,t14,t15,t16;

    _ARGCHK(pt != NULL);
    _ARGCHK(ct != NULL);
    _ARGCHK(skey != NULL);

    LOAD32L(a, &ct[0]);LOAD32L(b, &ct[4]);LOAD32L(c, &ct[8]);LOAD32L(d, &ct[12]);
    k_xor(32,a,b,c,d); ib7(a,b,c,d,e,f,g,h); k_xor(31,e,f,g,h);
    irot(e,f,g,h); ib6(e,f,g,h,a,b,c,d); k_xor(30,a,b,c,d);
    irot(a,b,c,d); ib5(a,b,c,d,e,f,g,h); k_xor(29,e,f,g,h);
    irot(e,f,g,h); ib4(e,f,g,h,a,b,c,d); k_xor(28,a,b,c,d);
    irot(a,b,c,d); ib3(a,b,c,d,e,f,g,h); k_xor(27,e,f,g,h);
    irot(e,f,g,h); ib2(e,f,g,h,a,b,c,d); k_xor(26,a,b,c,d);
    irot(a,b,c,d); ib1(a,b,c,d,e,f,g,h); k_xor(25,e,f,g,h);
    irot(e,f,g,h); ib0(e,f,g,h,a,b,c,d); k_xor(24,a,b,c,d);
    irot(a,b,c,d); ib7(a,b,c,d,e,f,g,h); k_xor(23,e,f,g,h);
    irot(e,f,g,h); ib6(e,f,g,h,a,b,c,d); k_xor(22,a,b,c,d);
    irot(a,b,c,d); ib5(a,b,c,d,e,f,g,h); k_xor(21,e,f,g,h);
    irot(e,f,g,h); ib4(e,f,g,h,a,b,c,d); k_xor(20,a,b,c,d);
    irot(a,b,c,d); ib3(a,b,c,d,e,f,g,h); k_xor(19,e,f,g,h);
    irot(e,f,g,h); ib2(e,f,g,h,a,b,c,d); k_xor(18,a,b,c,d);
    irot(a,b,c,d); ib1(a,b,c,d,e,f,g,h); k_xor(17,e,f,g,h);
    irot(e,f,g,h); ib0(e,f,g,h,a,b,c,d); k_xor(16,a,b,c,d);
    irot(a,b,c,d); ib7(a,b,c,d,e,f,g,h); k_xor(15,e,f,g,h);
    irot(e,f,g,h); ib6(e,f,g,h,a,b,c,d); k_xor(14,a,b,c,d);
    irot(a,b,c,d); ib5(a,b,c,d,e,f,g,h); k_xor(13,e,f,g,h);
    irot(e,f,g,h); ib4(e,f,g,h,a,b,c,d); k_xor(12,a,b,c,d);
    irot(a,b,c,d); ib3(a,b,c,d,e,f,g,h); k_xor(11,e,f,g,h);
    irot(e,f,g,h); ib2(e,f,g,h,a,b,c,d); k_xor(10,a,b,c,d);
    irot(a,b,c,d); ib1(a,b,c,d,e,f,g,h); k_xor( 9,e,f,g,h);
    irot(e,f,g,h); ib0(e,f,g,h,a,b,c,d); k_xor( 8,a,b,c,d);
    irot(a,b,c,d); ib7(a,b,c,d,e,f,g,h); k_xor( 7,e,f,g,h);
    irot(e,f,g,h); ib6(e,f,g,h,a,b,c,d); k_xor( 6,a,b,c,d);
    irot(a,b,c,d); ib5(a,b,c,d,e,f,g,h); k_xor( 5,e,f,g,h);
    irot(e,f,g,h); ib4(e,f,g,h,a,b,c,d); k_xor( 4,a,b,c,d);
    irot(a,b,c,d); ib3(a,b,c,d,e,f,g,h); k_xor( 3,e,f,g,h);
    irot(e,f,g,h); ib2(e,f,g,h,a,b,c,d); k_xor( 2,a,b,c,d);
    irot(a,b,c,d); ib1(a,b,c,d,e,f,g,h); k_xor( 1,e,f,g,h);
    irot(e,f,g,h); ib0(e,f,g,h,a,b,c,d); k_xor( 0,a,b,c,d);
    STORE32L(a, &pt[0]);STORE32L(b, &pt[4]);STORE32L(c, &pt[8]);STORE32L(d, &pt[12]);
}

#ifdef CLEAN_STACK
void serpent_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey)
{
   _serpent_ecb_decrypt(ct, pt, skey);
   burn_stack(sizeof(unsigned long)*24);
}
#endif

int serpent_test(void)
{
   static const struct {
       int keylen;
       unsigned char key[32], pt[16], ct[16];
   } tests[] = {
   {
      16,
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0xdd, 0xd2, 0x6b, 0x98, 0xa5, 0xff, 0xd8, 0x2c,
        0x05, 0x34, 0x5a, 0x9d, 0xad, 0xbf, 0xaf, 0x49 }
   },
   {
      16,
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80 },
      { 0x4a, 0xe9, 0xa2, 0x0b, 0x2b, 0x14, 0xa1, 0x02,
        0x90, 0xcb, 0xb8, 0x20, 0xb7, 0xff, 0xb5, 0x10 }
   },
   {
      24,
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08 },
      { 0xe1, 0x1b, 0x01, 0x52, 0x4e, 0xa1, 0xf4, 0x65, 
        0xa2, 0xa2, 0x00, 0x43, 0xeb, 0x9f, 0x7e, 0x8a }
   },
   {
      32,
      { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0xe0, 0x88, 0x5d, 0x44, 0x60, 0x37, 0x34, 0x69,
        0xd1, 0xfa, 0x6c, 0x36, 0xa6, 0xe1, 0xc5, 0x2f }
   },
   {
      32,
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x17, 0xc6, 0x25, 0x8e, 0x60, 0x09, 0xe2, 0x82,
        0x66, 0x18, 0x69, 0xd5, 0x25, 0xf7, 0xd2, 0x04 }
   },
   {
      32,
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
      { 0x9f, 0xe1, 0x43, 0x25, 0x0d, 0x00, 0xe2, 0x56, 
        0x96, 0xb0, 0x1e, 0x0a, 0x2e, 0xd0, 0x5d, 0xb3 }
   }
   };

   unsigned char buf[2][16];
   int x, failed, errno;
   symmetric_key key;

   for (x = failed = 0; x < (int)(sizeof(tests) / sizeof(tests[0])); x++) {
      /* setup key */
      if ((errno = serpent_setup(tests[x].key, tests[x].keylen, 0, &key))!= CRYPT_OK) {
         return errno;
      }

      /* encrypt and decrypt */
      serpent_ecb_encrypt(tests[x].pt, buf[0], &key);
      serpent_ecb_decrypt(buf[0], buf[1], &key);

      /* compare */
      if (memcmp(buf[0], tests[x].ct, 16)) {
#if 0
         int y;
         printf("\nEncrypt test %d failed\n", x);
         for (y = 0; y < 16; y++) printf("%02x ", buf[0][y]);
         printf("\n");
#endif
         failed = 1;
      }

      if (memcmp(buf[1], tests[x].pt, 16)) {
#if 0
         int y;
         printf("\nDecrypt test %d failed\n", x);
         for (y = 0; y < 16; y++) printf("%02x ", buf[1][y]);
         printf("\n");
#endif
         failed = 1;
      }
   }

   if (failed == 1) {
      return CRYPT_FAIL_TESTVECTOR;
   } else {
      return CRYPT_OK;
   }
}

int serpent_keysize(int *desired_keysize)
{
   _ARGCHK(desired_keysize != NULL);

   if (*desired_keysize < 16)
      return CRYPT_INVALID_KEYSIZE;
   if (*desired_keysize > 32)
      *desired_keysize = 32;
   return CRYPT_OK;
}

#endif