text: // SPDX-License-Identifier: BSD-2-Clause
  /* 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.
   */
  /**
     @file noekeon.c
     Implementation of the Noekeon block cipher by Tom St Denis
  */
  #include "tomcrypt_private.h"
  
  #ifdef LTC_NOEKEON
  
  const struct ltc_cipher_descriptor noekeon_desc =
  {
      "noekeon",
      16,
      16, 16, 16, 16,
      &noekeon_setup,
      &noekeon_ecb_encrypt,
      &noekeon_ecb_decrypt,
      &noekeon_test,
      &noekeon_done,
      &noekeon_keysize,
      NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
  };
  
  static const ulong32 RC[] = {
     0x00000080UL, 0x0000001bUL, 0x00000036UL, 0x0000006cUL,
     0x000000d8UL, 0x000000abUL, 0x0000004dUL, 0x0000009aUL,
     0x0000002fUL, 0x0000005eUL, 0x000000bcUL, 0x00000063UL,
     0x000000c6UL, 0x00000097UL, 0x00000035UL, 0x0000006aUL,
     0x000000d4UL
  };
  
  #define kTHETA(a, b, c, d)                                 \
      temp = a^c; temp = temp ^ ROLc(temp, 8) ^ RORc(temp, 8); \
      b ^= temp; d ^= temp;                                  \
      temp = b^d; temp = temp ^ ROLc(temp, 8) ^ RORc(temp, 8); \
      a ^= temp; c ^= temp;
  
  #define THETA(k, a, b, c, d)                               \
      temp = a^c; temp = temp ^ ROLc(temp, 8) ^ RORc(temp, 8); \
      b ^= temp ^ k[1]; d ^= temp ^ k[3];                    \
      temp = b^d; temp = temp ^ ROLc(temp, 8) ^ RORc(temp, 8); \
      a ^= temp ^ k[0]; c ^= temp ^ k[2];
  
  #define GAMMA(a, b, c, d)     \
      b ^= ~(d|c);              \
      a ^= c&b;                 \
      temp = d; d = a; a = temp;\
      c ^= a ^ b ^ d;           \
      b ^= ~(d|c);              \
      a ^= c&b;
  
  #define PI1(a, b, c, d) \
      b = ROLc(b, 1); c = ROLc(c, 5); d = ROLc(d, 2);
  
  #define PI2(a, b, c, d) \
      b = RORc(b, 1); c = RORc(c, 5); d = RORc(d, 2);
  
   /**
      Initialize the Noekeon block cipher
      @param key The symmetric key you wish to pass
      @param keylen The key length in bytes
      @param num_rounds The number of rounds desired (0 for default)
      @param skey The key in as scheduled by this function.
      @return CRYPT_OK if successful
   */
  int noekeon_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
  {
     ulong32 temp;
  
     LTC_ARGCHK(key != NULL);
     LTC_ARGCHK(skey != NULL);
  
     if (keylen != 16) {
        return CRYPT_INVALID_KEYSIZE;
     }
  
     if (num_rounds != 16 && num_rounds != 0) {
        return CRYPT_INVALID_ROUNDS;
     }
  
     LOAD32H(skey->noekeon.K[0],&key[0]);
     LOAD32H(skey->noekeon.K[1],&key[4]);
     LOAD32H(skey->noekeon.K[2],&key[8]);
     LOAD32H(skey->noekeon.K[3],&key[12]);
  
     LOAD32H(skey->noekeon.dK[0],&key[0]);
     LOAD32H(skey->noekeon.dK[1],&key[4]);
     LOAD32H(skey->noekeon.dK[2],&key[8]);
     LOAD32H(skey->noekeon.dK[3],&key[12]);
  
     kTHETA(skey->noekeon.dK[0], skey->noekeon.dK[1], skey->noekeon.dK[2], skey->noekeon.dK[3]);
  
     return CRYPT_OK;
  }
  
  /**
    Encrypts a block of text with Noekeon
    @param pt The input plaintext (16 bytes)
    @param ct The output ciphertext (16 bytes)
    @param skey The key as scheduled
    @return CRYPT_OK if successful
  */
  #ifdef LTC_CLEAN_STACK
  static int _noekeon_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric_key *skey)
  #else
  int noekeon_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric_key *skey)
  #endif
  {
     ulong32 a,b,c,d,temp;
     int r;
  
     LTC_ARGCHK(skey != NULL);
     LTC_ARGCHK(pt   != NULL);
     LTC_ARGCHK(ct   != NULL);
  
     LOAD32H(a,&pt[0]); LOAD32H(b,&pt[4]);
     LOAD32H(c,&pt[8]); LOAD32H(d,&pt[12]);
  
  #define ROUND(i) \
         a ^= RC[i]; \
         THETA(skey->noekeon.K, a,b,c,d); \
         PI1(a,b,c,d); \
         GAMMA(a,b,c,d); \
         PI2(a,b,c,d);
  
     for (r = 0; r < 16; ++r) {
         ROUND(r);
     }
  
  #undef ROUND
  
     a ^= RC[16];
     THETA(skey->noekeon.K, a, b, c, d);
  
     STORE32H(a,&ct[0]); STORE32H(b,&ct[4]);
     STORE32H(c,&ct[8]); STORE32H(d,&ct[12]);
  
     return CRYPT_OK;
  }
  
  #ifdef LTC_CLEAN_STACK
  int noekeon_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric_key *skey)
  {
     int err = _noekeon_ecb_encrypt(pt, ct, skey);
     burn_stack(sizeof(ulong32) * 5 + sizeof(int));
     return err;
  }
  #endif
  
  /**
    Decrypts a block of text with Noekeon
    @param ct The input ciphertext (16 bytes)
    @param pt The output plaintext (16 bytes)
    @param skey The key as scheduled
    @return CRYPT_OK if successful
  */
  #ifdef LTC_CLEAN_STACK
  static int _noekeon_ecb_decrypt(const unsigned char *ct, unsigned char *pt, const symmetric_key *skey)
  #else
  int noekeon_ecb_decrypt(const unsigned char *ct, unsigned char *pt, const symmetric_key *skey)
  #endif
  {
     ulong32 a,b,c,d, temp;
     int r;
  
     LTC_ARGCHK(skey != NULL);
     LTC_ARGCHK(pt   != NULL);
     LTC_ARGCHK(ct   != NULL);
  
     LOAD32H(a,&ct[0]); LOAD32H(b,&ct[4]);
     LOAD32H(c,&ct[8]); LOAD32H(d,&ct[12]);
  
  
  #define ROUND(i) \
         THETA(skey->noekeon.dK, a,b,c,d); \
         a ^= RC[i]; \
         PI1(a,b,c,d); \
         GAMMA(a,b,c,d); \
         PI2(a,b,c,d);
  
     for (r = 16; r > 0; --r) {
         ROUND(r);
     }
  
  #undef ROUND
  
     THETA(skey->noekeon.dK, a,b,c,d);
     a ^= RC[0];
     STORE32H(a,&pt[0]); STORE32H(b, &pt[4]);
     STORE32H(c,&pt[8]); STORE32H(d, &pt[12]);
     return CRYPT_OK;
  }
  
  #ifdef LTC_CLEAN_STACK
  int noekeon_ecb_decrypt(const unsigned char *ct, unsigned char *pt, const symmetric_key *skey)
  {
     int err = _noekeon_ecb_decrypt(ct, pt, skey);
     burn_stack(sizeof(ulong32) * 5 + sizeof(int));
     return err;
  }
  #endif
  
  /**
    Performs a self-test of the Noekeon block cipher
    @return CRYPT_OK if functional, CRYPT_NOP if self-test has been disabled
  */
  int noekeon_test(void)
  {
   #ifndef LTC_TEST
      return CRYPT_NOP;
   #else
   static const struct {
       int keylen;
       unsigned char key[16], pt[16], ct[16];
   } tests[] = {
     {
        16,
        { 0xAA, 0x3C, 0x8C, 0x86, 0xD9, 0x8B, 0xF8, 0xBE, 0x21, 0xE0, 0x36, 0x09, 0x78, 0xFB, 0xE4, 0x90 },
        { 0xE4, 0x96, 0x6C, 0xD3, 0x13, 0xA0, 0x6C, 0xAF, 0xD0, 0x23, 0xC9, 0xFD, 0x45, 0x32, 0x23, 0x16 },
        { 0xA6, 0xEC, 0xB8, 0xA8, 0x61, 0xFD, 0x62, 0xD9, 0x13, 0x02, 0xFE, 0x9E, 0x47, 0x01, 0x3F, 0xC3 }
     },
     {
        16,
        { 0xED, 0x43, 0xD1, 0x87, 0x21, 0x7E, 0xE0, 0x97, 0x3D, 0x76, 0xC3, 0x37, 0x2E, 0x7D, 0xAE, 0xD3 },
        { 0xE3, 0x38, 0x32, 0xCC, 0xF2, 0x2F, 0x2F, 0x0A, 0x4A, 0x8B, 0x8F, 0x18, 0x12, 0x20, 0x17, 0xD3 },
        { 0x94, 0xA5, 0xDF, 0xF5, 0xAE, 0x1C, 0xBB, 0x22, 0xAD, 0xEB, 0xA7, 0x0D, 0xB7, 0x82, 0x90, 0xA0 }
     },
     {
        16,
        { 0x6F, 0xDC, 0x23, 0x38, 0xF2, 0x10, 0xFB, 0xD3, 0xC1, 0x8C, 0x02, 0xF6, 0xB4, 0x6A, 0xD5, 0xA8 },
        { 0xDB, 0x29, 0xED, 0xB5, 0x5F, 0xB3, 0x60, 0x3A, 0x92, 0xA8, 0xEB, 0x9C, 0x6D, 0x9D, 0x3E, 0x8F },
        { 0x78, 0xF3, 0x6F, 0xF8, 0x9E, 0xBB, 0x8C, 0x6A, 0xE8, 0x10, 0xF7, 0x00, 0x22, 0x15, 0x30, 0x3D }
     },
     {
        16,
        { 0x2C, 0x0C, 0x02, 0xEF, 0x6B, 0xC4, 0xF2, 0x0B, 0x2E, 0xB9, 0xE0, 0xBF, 0xD9, 0x36, 0xC2, 0x4E },
        { 0x84, 0xE2, 0xFE, 0x64, 0xB1, 0xB9, 0xFE, 0x76, 0xA8, 0x3F, 0x45, 0xC7, 0x40, 0x7A, 0xAF, 0xEE },
        { 0x2A, 0x08, 0xD6, 0xA2, 0x1C, 0x63, 0x08, 0xB0, 0xF8, 0xBC, 0xB3, 0xA1, 0x66, 0xF7, 0xAE, 0xCF }
     },
     {
        16,
        { 0x6F, 0x30, 0xF8, 0x9F, 0xDA, 0x6E, 0xA0, 0x91, 0x04, 0x0F, 0x6C, 0x8B, 0x7D, 0xF7, 0x2A, 0x4B },
        { 0x65, 0xB6, 0xA6, 0xD0, 0x42, 0x14, 0x08, 0x60, 0x34, 0x8D, 0x37, 0x2F, 0x01, 0xF0, 0x46, 0xBE },
        { 0x66, 0xAC, 0x0B, 0x62, 0x1D, 0x68, 0x11, 0xF5, 0x27, 0xB1, 0x13, 0x5D, 0xF3, 0x2A, 0xE9, 0x18 }
     },
     {
        16,
        { 0xCA, 0xA4, 0x16, 0xB7, 0x1C, 0x92, 0x2E, 0xAD, 0xEB, 0xA7, 0xDB, 0x69, 0x92, 0xCB, 0x35, 0xEF },
        { 0x81, 0x6F, 0x8E, 0x4D, 0x96, 0xC6, 0xB3, 0x67, 0x83, 0xF5, 0x63, 0xC7, 0x20, 0x6D, 0x40, 0x23 },
        { 0x44, 0xF7, 0x63, 0x62, 0xF0, 0x43, 0xBB, 0x67, 0x4A, 0x75, 0x12, 0x42, 0x46, 0x29, 0x28, 0x19 }
     },
     {
        16,
        { 0x6B, 0xCF, 0x22, 0x2F, 0xE0, 0x1B, 0xB0, 0xAA, 0xD8, 0x3C, 0x91, 0x99, 0x18, 0xB2, 0x28, 0xE8 },
        { 0x7C, 0x37, 0xC7, 0xD0, 0xAC, 0x92, 0x29, 0xF1, 0x60, 0x82, 0x93, 0x89, 0xAA, 0x61, 0xAA, 0xA9 },
        { 0xE5, 0x89, 0x1B, 0xB3, 0xFE, 0x8B, 0x0C, 0xA1, 0xA6, 0xC7, 0xBE, 0x12, 0x73, 0x0F, 0xC1, 0x19 }
     },
     {
        16,
        { 0xE6, 0xD0, 0xF1, 0x03, 0x2E, 0xDE, 0x70, 0x8D, 0xD8, 0x9E, 0x36, 0x5C, 0x05, 0x52, 0xE7, 0x0D },
        { 0xE2, 0x42, 0xE7, 0x92, 0x0E, 0xF7, 0x82, 0xA2, 0xB8, 0x21, 0x8D, 0x26, 0xBA, 0x2D, 0xE6, 0x32 },
        { 0x1E, 0xDD, 0x75, 0x22, 0xB9, 0x36, 0x8A, 0x0F, 0x32, 0xFD, 0xD4, 0x48, 0x65, 0x12, 0x5A, 0x2F }
     }
   };
   symmetric_key key;
   unsigned char tmp[2][16];
   int err, i, y;
  
   for (i = 0; i < (int)(sizeof(tests)/sizeof(tests[0])); i++) {
      zeromem(&key, sizeof(key));
      if ((err = noekeon_setup(tests[i].key, tests[i].keylen, 0, &key)) != CRYPT_OK) {
         return err;
      }
  
      noekeon_ecb_encrypt(tests[i].pt, tmp[0], &key);
      noekeon_ecb_decrypt(tmp[0], tmp[1], &key);
      if (compare_testvector(tmp[0], 16, tests[i].ct, 16, "Noekeon Encrypt", i) ||
            compare_testvector(tmp[1], 16, tests[i].pt, 16, "Noekeon Decrypt", i)) {
          return CRYPT_FAIL_TESTVECTOR;
      }
  
      /* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */
      for (y = 0; y < 16; y++) tmp[0][y] = 0;
      for (y = 0; y < 1000; y++) noekeon_ecb_encrypt(tmp[0], tmp[0], &key);
      for (y = 0; y < 1000; y++) noekeon_ecb_decrypt(tmp[0], tmp[0], &key);
      for (y = 0; y < 16; y++) if (tmp[0][y] != 0) return CRYPT_FAIL_TESTVECTOR;
   }
   return CRYPT_OK;
   #endif
  }
  
  /** Terminate the context
     @param skey    The scheduled key
  */
  void noekeon_done(symmetric_key *skey)
  {
    LTC_UNUSED_PARAM(skey);
  }
  
  /**
    Gets suitable key size
    @param keysize [in/out] The length of the recommended key (in bytes).  This function will store the suitable size back in this variable.
    @return CRYPT_OK if the input key size is acceptable.
  */
  int noekeon_keysize(int *keysize)
  {
     LTC_ARGCHK(keysize != NULL);
     if (*keysize < 16) {
        return CRYPT_INVALID_KEYSIZE;
     }
     *keysize = 16;
     return CRYPT_OK;
  }
  
  #endif
  
  
  /* ref:         $Format:%D$ */
  /* git commit:  $Format:%H$ */
  /* commit time: $Format:%ai$ */
  