view libtomcrypt/src/hashes/sha3.c @ 1653:76189c9ffea2

External Public-Key Authentication API (#72) * Implemented dynamic loading of an external plug-in shared library to delegate public key authentication * Moved conditional compilation of the plugin infrastructure into the configure.ac script to be able to add -ldl to dropbear build only when the flag is enabled * Added tags file to the ignore list * Updated API to have the constructor to return function pointers in the pliugin instance. Added support for passing user name to the checkpubkey function. Added options to the session returned by the plugin and have dropbear to parse and process them * Added -rdynamic to the linker flags when EPKA is enabled * Changed the API to pass a previously created session to the checkPubKey function (created during preauth) * Added documentation to the API * Added parameter addrstring to plugin creation function * Modified the API to retrieve the auth options. Instead of having them as field of the EPKASession struct, they are stored internally (plugin-dependent) in the plugin/session and retrieved through a pointer to a function (in the session) * Changed option string to be a simple char * instead of unsigned char *
author fabriziobertocci <fabriziobertocci@gmail.com>
date Wed, 15 May 2019 09:43:57 -0400
parents 6dba84798cd5
children
line wrap: on
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/* 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.
 */

/* based on https://github.com/brainhub/SHA3IUF (public domain) */

#include "tomcrypt.h"

#ifdef LTC_SHA3

const struct ltc_hash_descriptor sha3_224_desc =
{
   "sha3-224",                  /* name of hash */
   17,                          /* internal ID */
   28,                          /* Size of digest in octets */
   144,                         /* Input block size in octets */
   { 2,16,840,1,101,3,4,2,7 },  /* ASN.1 OID */
   9,                           /* Length OID */
   &sha3_224_init,
   &sha3_process,
   &sha3_done,
   &sha3_224_test,
   NULL
};

const struct ltc_hash_descriptor sha3_256_desc =
{
   "sha3-256",                  /* name of hash */
   18,                          /* internal ID */
   32,                          /* Size of digest in octets */
   136,                         /* Input block size in octets */
   { 2,16,840,1,101,3,4,2,8 },  /* ASN.1 OID */
   9,                           /* Length OID */
   &sha3_256_init,
   &sha3_process,
   &sha3_done,
   &sha3_256_test,
   NULL
};

const struct ltc_hash_descriptor sha3_384_desc =
{
   "sha3-384",                  /* name of hash */
   19,                          /* internal ID */
   48,                          /* Size of digest in octets */
   104,                         /* Input block size in octets */
   { 2,16,840,1,101,3,4,2,9 },  /* ASN.1 OID */
   9,                           /* Length OID */
   &sha3_384_init,
   &sha3_process,
   &sha3_done,
   &sha3_384_test,
   NULL
};

const struct ltc_hash_descriptor sha3_512_desc =
{
   "sha3-512",                  /* name of hash */
   20,                          /* internal ID */
   64,                          /* Size of digest in octets */
   72,                          /* Input block size in octets */
   { 2,16,840,1,101,3,4,2,10 }, /* ASN.1 OID */
   9,                           /* Length OID */
   &sha3_512_init,
   &sha3_process,
   &sha3_done,
   &sha3_512_test,
   NULL
};

#define SHA3_KECCAK_SPONGE_WORDS 25 /* 1600 bits > 200 bytes > 25 x ulong64 */
#define SHA3_KECCAK_ROUNDS 24

static const ulong64 keccakf_rndc[24] = {
   CONST64(0x0000000000000001), CONST64(0x0000000000008082),
   CONST64(0x800000000000808a), CONST64(0x8000000080008000),
   CONST64(0x000000000000808b), CONST64(0x0000000080000001),
   CONST64(0x8000000080008081), CONST64(0x8000000000008009),
   CONST64(0x000000000000008a), CONST64(0x0000000000000088),
   CONST64(0x0000000080008009), CONST64(0x000000008000000a),
   CONST64(0x000000008000808b), CONST64(0x800000000000008b),
   CONST64(0x8000000000008089), CONST64(0x8000000000008003),
   CONST64(0x8000000000008002), CONST64(0x8000000000000080),
   CONST64(0x000000000000800a), CONST64(0x800000008000000a),
   CONST64(0x8000000080008081), CONST64(0x8000000000008080),
   CONST64(0x0000000080000001), CONST64(0x8000000080008008)
};

static const unsigned keccakf_rotc[24] = {
   1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 2, 14, 27, 41, 56, 8, 25, 43, 62, 18, 39, 61, 20, 44
};

static const unsigned keccakf_piln[24] = {
   10, 7, 11, 17, 18, 3, 5, 16, 8, 21, 24, 4, 15, 23, 19, 13, 12, 2, 20, 14, 22, 9, 6, 1
};

static void keccakf(ulong64 s[25])
{
   int i, j, round;
   ulong64 t, bc[5];

   for(round = 0; round < SHA3_KECCAK_ROUNDS; round++) {
      /* Theta */
      for(i = 0; i < 5; i++)
         bc[i] = s[i] ^ s[i + 5] ^ s[i + 10] ^ s[i + 15] ^ s[i + 20];

      for(i = 0; i < 5; i++) {
         t = bc[(i + 4) % 5] ^ ROL64(bc[(i + 1) % 5], 1);
         for(j = 0; j < 25; j += 5)
            s[j + i] ^= t;
      }
      /* Rho Pi */
      t = s[1];
      for(i = 0; i < 24; i++) {
         j = keccakf_piln[i];
         bc[0] = s[j];
         s[j] = ROL64(t, keccakf_rotc[i]);
         t = bc[0];
      }
      /* Chi */
      for(j = 0; j < 25; j += 5) {
         for(i = 0; i < 5; i++)
            bc[i] = s[j + i];
         for(i = 0; i < 5; i++)
            s[j + i] ^= (~bc[(i + 1) % 5]) & bc[(i + 2) % 5];
      }
      /* Iota */
      s[0] ^= keccakf_rndc[round];
   }
}

/* Public Inteface */

int sha3_224_init(hash_state *md)
{
   LTC_ARGCHK(md != NULL);
   XMEMSET(&md->sha3, 0, sizeof(md->sha3));
   md->sha3.capacity_words = 2 * 224 / (8 * sizeof(ulong64));
   return CRYPT_OK;
}

int sha3_256_init(hash_state *md)
{
   LTC_ARGCHK(md != NULL);
   XMEMSET(&md->sha3, 0, sizeof(md->sha3));
   md->sha3.capacity_words = 2 * 256 / (8 * sizeof(ulong64));
   return CRYPT_OK;
}

int sha3_384_init(hash_state *md)
{
   LTC_ARGCHK(md != NULL);
   XMEMSET(&md->sha3, 0, sizeof(md->sha3));
   md->sha3.capacity_words = 2 * 384 / (8 * sizeof(ulong64));
   return CRYPT_OK;
}

int sha3_512_init(hash_state *md)
{
   LTC_ARGCHK(md != NULL);
   XMEMSET(&md->sha3, 0, sizeof(md->sha3));
   md->sha3.capacity_words = 2 * 512 / (8 * sizeof(ulong64));
   return CRYPT_OK;
}

int sha3_shake_init(hash_state *md, int num)
{
   LTC_ARGCHK(md != NULL);
   if (num != 128 && num != 256) return CRYPT_INVALID_ARG;
   XMEMSET(&md->sha3, 0, sizeof(md->sha3));
   md->sha3.capacity_words = (unsigned short)(2 * num / (8 * sizeof(ulong64)));
   return CRYPT_OK;
}

int sha3_process(hash_state *md, const unsigned char *in, unsigned long inlen)
{
   /* 0...7 -- how much is needed to have a word */
   unsigned old_tail = (8 - md->sha3.byte_index) & 7;

   unsigned long words;
   unsigned tail;
   unsigned long i;

   if (inlen == 0) return CRYPT_OK; /* nothing to do */
   LTC_ARGCHK(md != NULL);
   LTC_ARGCHK(in != NULL);

   if(inlen < old_tail) {       /* have no complete word or haven't started the word yet */
      while (inlen--) md->sha3.saved |= (ulong64) (*(in++)) << ((md->sha3.byte_index++) * 8);
      return CRYPT_OK;
   }

   if(old_tail) {               /* will have one word to process */
      inlen -= old_tail;
      while (old_tail--) md->sha3.saved |= (ulong64) (*(in++)) << ((md->sha3.byte_index++) * 8);
      /* now ready to add saved to the sponge */
      md->sha3.s[md->sha3.word_index] ^= md->sha3.saved;
      md->sha3.byte_index = 0;
      md->sha3.saved = 0;
      if(++md->sha3.word_index == (SHA3_KECCAK_SPONGE_WORDS - md->sha3.capacity_words)) {
         keccakf(md->sha3.s);
         md->sha3.word_index = 0;
      }
   }

   /* now work in full words directly from input */
   words = inlen / sizeof(ulong64);
   tail = inlen - words * sizeof(ulong64);

   for(i = 0; i < words; i++, in += sizeof(ulong64)) {
      ulong64 t;
      LOAD64L(t, in);
      md->sha3.s[md->sha3.word_index] ^= t;
      if(++md->sha3.word_index == (SHA3_KECCAK_SPONGE_WORDS - md->sha3.capacity_words)) {
         keccakf(md->sha3.s);
         md->sha3.word_index = 0;
      }
   }

   /* finally, save the partial word */
   while (tail--) {
      md->sha3.saved |= (ulong64) (*(in++)) << ((md->sha3.byte_index++) * 8);
   }
   return CRYPT_OK;
}

int sha3_done(hash_state *md, unsigned char *hash)
{
   unsigned i;

   LTC_ARGCHK(md   != NULL);
   LTC_ARGCHK(hash != NULL);

   md->sha3.s[md->sha3.word_index] ^= (md->sha3.saved ^ (CONST64(0x06) << (md->sha3.byte_index * 8)));
   md->sha3.s[SHA3_KECCAK_SPONGE_WORDS - md->sha3.capacity_words - 1] ^= CONST64(0x8000000000000000);
   keccakf(md->sha3.s);

   /* store sha3.s[] as little-endian bytes into sha3.sb */
   for(i = 0; i < SHA3_KECCAK_SPONGE_WORDS; i++) {
      STORE64L(md->sha3.s[i], md->sha3.sb + i * 8);
   }

   XMEMCPY(hash, md->sha3.sb, md->sha3.capacity_words * 4);
   return CRYPT_OK;
}

int sha3_shake_done(hash_state *md, unsigned char *out, unsigned long outlen)
{
   /* IMPORTANT NOTE: sha3_shake_done can be called many times */
   unsigned long idx;
   unsigned i;

   if (outlen == 0) return CRYPT_OK; /* nothing to do */
   LTC_ARGCHK(md  != NULL);
   LTC_ARGCHK(out != NULL);

   if (!md->sha3.xof_flag) {
      /* shake_xof operation must be done only once */
      md->sha3.s[md->sha3.word_index] ^= (md->sha3.saved ^ (CONST64(0x1F) << (md->sha3.byte_index * 8)));
      md->sha3.s[SHA3_KECCAK_SPONGE_WORDS - md->sha3.capacity_words - 1] ^= CONST64(0x8000000000000000);
      keccakf(md->sha3.s);
      /* store sha3.s[] as little-endian bytes into sha3.sb */
      for(i = 0; i < SHA3_KECCAK_SPONGE_WORDS; i++) {
         STORE64L(md->sha3.s[i], md->sha3.sb + i * 8);
      }
      md->sha3.byte_index = 0;
      md->sha3.xof_flag = 1;
   }

   for (idx = 0; idx < outlen; idx++) {
      if(md->sha3.byte_index >= (SHA3_KECCAK_SPONGE_WORDS - md->sha3.capacity_words) * 8) {
         keccakf(md->sha3.s);
         /* store sha3.s[] as little-endian bytes into sha3.sb */
         for(i = 0; i < SHA3_KECCAK_SPONGE_WORDS; i++) {
            STORE64L(md->sha3.s[i], md->sha3.sb + i * 8);
         }
         md->sha3.byte_index = 0;
      }
      out[idx] = md->sha3.sb[md->sha3.byte_index++];
   }
   return CRYPT_OK;
}

int sha3_shake_memory(int num, const unsigned char *in, unsigned long inlen, unsigned char *out, unsigned long *outlen)
{
   hash_state md;
   int err;
   LTC_ARGCHK(in  != NULL);
   LTC_ARGCHK(out != NULL);
   LTC_ARGCHK(outlen != NULL);
   if ((err = sha3_shake_init(&md, num))          != CRYPT_OK) return err;
   if ((err = sha3_shake_process(&md, in, inlen)) != CRYPT_OK) return err;
   if ((err = sha3_shake_done(&md, out, *outlen)) != CRYPT_OK) return err;
   return CRYPT_OK;
}

#endif

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