view libtomcrypt/src/hashes/sha2/sha512.c @ 1790:42745af83b7d

Introduce extra delay before closing unauthenticated sessions To make it harder for attackers, introduce a delay to keep an unauthenticated session open a bit longer, thus blocking a connection slot until after the delay. Without this, while there is a limit on the amount of attempts an attacker can make at the same time (MAX_UNAUTH_PER_IP), the time taken by dropbear to handle one attempt is still short and thus for each of the allowed parallel attempts many attempts can be chained one after the other. The attempt rate is then: "MAX_UNAUTH_PER_IP / <process time of one attempt>". With the delay, this rate becomes: "MAX_UNAUTH_PER_IP / UNAUTH_CLOSE_DELAY".
author Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
date Wed, 15 Feb 2017 13:53:04 +0100
parents 6dba84798cd5
children
line wrap: on
line source

/* 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"

/**
   @param sha512.c
   LTC_SHA512 by Tom St Denis
*/

#ifdef LTC_SHA512

const struct ltc_hash_descriptor sha512_desc =
{
    "sha512",
    5,
    64,
    128,

    /* OID */
   { 2, 16, 840, 1, 101, 3, 4, 2, 3,  },
   9,

    &sha512_init,
    &sha512_process,
    &sha512_done,
    &sha512_test,
    NULL
};

/* the K array */
static const ulong64 K[80] = {
CONST64(0x428a2f98d728ae22), CONST64(0x7137449123ef65cd),
CONST64(0xb5c0fbcfec4d3b2f), CONST64(0xe9b5dba58189dbbc),
CONST64(0x3956c25bf348b538), CONST64(0x59f111f1b605d019),
CONST64(0x923f82a4af194f9b), CONST64(0xab1c5ed5da6d8118),
CONST64(0xd807aa98a3030242), CONST64(0x12835b0145706fbe),
CONST64(0x243185be4ee4b28c), CONST64(0x550c7dc3d5ffb4e2),
CONST64(0x72be5d74f27b896f), CONST64(0x80deb1fe3b1696b1),
CONST64(0x9bdc06a725c71235), CONST64(0xc19bf174cf692694),
CONST64(0xe49b69c19ef14ad2), CONST64(0xefbe4786384f25e3),
CONST64(0x0fc19dc68b8cd5b5), CONST64(0x240ca1cc77ac9c65),
CONST64(0x2de92c6f592b0275), CONST64(0x4a7484aa6ea6e483),
CONST64(0x5cb0a9dcbd41fbd4), CONST64(0x76f988da831153b5),
CONST64(0x983e5152ee66dfab), CONST64(0xa831c66d2db43210),
CONST64(0xb00327c898fb213f), CONST64(0xbf597fc7beef0ee4),
CONST64(0xc6e00bf33da88fc2), CONST64(0xd5a79147930aa725),
CONST64(0x06ca6351e003826f), CONST64(0x142929670a0e6e70),
CONST64(0x27b70a8546d22ffc), CONST64(0x2e1b21385c26c926),
CONST64(0x4d2c6dfc5ac42aed), CONST64(0x53380d139d95b3df),
CONST64(0x650a73548baf63de), CONST64(0x766a0abb3c77b2a8),
CONST64(0x81c2c92e47edaee6), CONST64(0x92722c851482353b),
CONST64(0xa2bfe8a14cf10364), CONST64(0xa81a664bbc423001),
CONST64(0xc24b8b70d0f89791), CONST64(0xc76c51a30654be30),
CONST64(0xd192e819d6ef5218), CONST64(0xd69906245565a910),
CONST64(0xf40e35855771202a), CONST64(0x106aa07032bbd1b8),
CONST64(0x19a4c116b8d2d0c8), CONST64(0x1e376c085141ab53),
CONST64(0x2748774cdf8eeb99), CONST64(0x34b0bcb5e19b48a8),
CONST64(0x391c0cb3c5c95a63), CONST64(0x4ed8aa4ae3418acb),
CONST64(0x5b9cca4f7763e373), CONST64(0x682e6ff3d6b2b8a3),
CONST64(0x748f82ee5defb2fc), CONST64(0x78a5636f43172f60),
CONST64(0x84c87814a1f0ab72), CONST64(0x8cc702081a6439ec),
CONST64(0x90befffa23631e28), CONST64(0xa4506cebde82bde9),
CONST64(0xbef9a3f7b2c67915), CONST64(0xc67178f2e372532b),
CONST64(0xca273eceea26619c), CONST64(0xd186b8c721c0c207),
CONST64(0xeada7dd6cde0eb1e), CONST64(0xf57d4f7fee6ed178),
CONST64(0x06f067aa72176fba), CONST64(0x0a637dc5a2c898a6),
CONST64(0x113f9804bef90dae), CONST64(0x1b710b35131c471b),
CONST64(0x28db77f523047d84), CONST64(0x32caab7b40c72493),
CONST64(0x3c9ebe0a15c9bebc), CONST64(0x431d67c49c100d4c),
CONST64(0x4cc5d4becb3e42b6), CONST64(0x597f299cfc657e2a),
CONST64(0x5fcb6fab3ad6faec), CONST64(0x6c44198c4a475817)
};

/* 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)         ROR64c(x, n)
#define R(x, n)         (((x)&CONST64(0xFFFFFFFFFFFFFFFF))>>((ulong64)n))
#define Sigma0(x)       (S(x, 28) ^ S(x, 34) ^ S(x, 39))
#define Sigma1(x)       (S(x, 14) ^ S(x, 18) ^ S(x, 41))
#define Gamma0(x)       (S(x, 1) ^ S(x, 8) ^ R(x, 7))
#define Gamma1(x)       (S(x, 19) ^ S(x, 61) ^ R(x, 6))

/* compress 1024-bits */
#ifdef LTC_CLEAN_STACK
static int _sha512_compress(hash_state * md, unsigned char *buf)
#else
static int  sha512_compress(hash_state * md, unsigned char *buf)
#endif
{
    ulong64 S[8], W[80], t0, t1;
    int i;

    /* copy state into S */
    for (i = 0; i < 8; i++) {
        S[i] = md->sha512.state[i];
    }

    /* copy the state into 1024-bits into W[0..15] */
    for (i = 0; i < 16; i++) {
        LOAD64H(W[i], buf + (8*i));
    }

    /* fill W[16..79] */
    for (i = 16; i < 80; i++) {
        W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];
    }

    /* Compress */
#ifdef LTC_SMALL_CODE
    for (i = 0; i < 80; i++) {
        t0 = S[7] + Sigma1(S[4]) + Ch(S[4], S[5], S[6]) + K[i] + W[i];
        t1 = Sigma0(S[0]) + Maj(S[0], S[1], S[2]);
        S[7] = S[6];
        S[6] = S[5];
        S[5] = S[4];
        S[4] = S[3] + t0;
        S[3] = S[2];
        S[2] = S[1];
        S[1] = S[0];
        S[0] = t0 + t1;
    }
#else
#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 < 80; i += 8) {
        RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i+0);
        RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],i+1);
        RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],i+2);
        RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],i+3);
        RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],i+4);
        RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],i+5);
        RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],i+6);
        RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],i+7);
    }
#endif


    /* feedback */
    for (i = 0; i < 8; i++) {
        md->sha512.state[i] = md->sha512.state[i] + S[i];
    }

    return CRYPT_OK;
}

/* compress 1024-bits */
#ifdef LTC_CLEAN_STACK
static int sha512_compress(hash_state * md, unsigned char *buf)
{
    int err;
    err = _sha512_compress(md, buf);
    burn_stack(sizeof(ulong64) * 90 + sizeof(int));
    return err;
}
#endif

/**
   Initialize the hash state
   @param md   The hash state you wish to initialize
   @return CRYPT_OK if successful
*/
int sha512_init(hash_state * md)
{
    LTC_ARGCHK(md != NULL);
    md->sha512.curlen = 0;
    md->sha512.length = 0;
    md->sha512.state[0] = CONST64(0x6a09e667f3bcc908);
    md->sha512.state[1] = CONST64(0xbb67ae8584caa73b);
    md->sha512.state[2] = CONST64(0x3c6ef372fe94f82b);
    md->sha512.state[3] = CONST64(0xa54ff53a5f1d36f1);
    md->sha512.state[4] = CONST64(0x510e527fade682d1);
    md->sha512.state[5] = CONST64(0x9b05688c2b3e6c1f);
    md->sha512.state[6] = CONST64(0x1f83d9abfb41bd6b);
    md->sha512.state[7] = CONST64(0x5be0cd19137e2179);
    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(sha512_process, sha512_compress, sha512, 128)

/**
   Terminate the hash to get the digest
   @param md  The hash state
   @param out [out] The destination of the hash (64 bytes)
   @return CRYPT_OK if successful
*/
int sha512_done(hash_state * md, unsigned char *out)
{
    int i;

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

    if (md->sha512.curlen >= sizeof(md->sha512.buf)) {
       return CRYPT_INVALID_ARG;
    }

    /* increase the length of the message */
    md->sha512.length += md->sha512.curlen * CONST64(8);

    /* append the '1' bit */
    md->sha512.buf[md->sha512.curlen++] = (unsigned char)0x80;

    /* if the length is currently above 112 bytes we append zeros
     * then compress.  Then we can fall back to padding zeros and length
     * encoding like normal.
     */
    if (md->sha512.curlen > 112) {
        while (md->sha512.curlen < 128) {
            md->sha512.buf[md->sha512.curlen++] = (unsigned char)0;
        }
        sha512_compress(md, md->sha512.buf);
        md->sha512.curlen = 0;
    }

    /* pad upto 120 bytes of zeroes
     * note: that from 112 to 120 is the 64 MSB of the length.  We assume that you won't hash
     * > 2^64 bits of data... :-)
     */
    while (md->sha512.curlen < 120) {
        md->sha512.buf[md->sha512.curlen++] = (unsigned char)0;
    }

    /* store length */
    STORE64H(md->sha512.length, md->sha512.buf+120);
    sha512_compress(md, md->sha512.buf);

    /* copy output */
    for (i = 0; i < 8; i++) {
        STORE64H(md->sha512.state[i], out+(8*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  sha512_test(void)
{
 #ifndef LTC_TEST
    return CRYPT_NOP;
 #else
  static const struct {
      const char *msg;
      unsigned char hash[64];
  } tests[] = {
    { "abc",
     { 0xdd, 0xaf, 0x35, 0xa1, 0x93, 0x61, 0x7a, 0xba,
       0xcc, 0x41, 0x73, 0x49, 0xae, 0x20, 0x41, 0x31,
       0x12, 0xe6, 0xfa, 0x4e, 0x89, 0xa9, 0x7e, 0xa2,
       0x0a, 0x9e, 0xee, 0xe6, 0x4b, 0x55, 0xd3, 0x9a,
       0x21, 0x92, 0x99, 0x2a, 0x27, 0x4f, 0xc1, 0xa8,
       0x36, 0xba, 0x3c, 0x23, 0xa3, 0xfe, 0xeb, 0xbd,
       0x45, 0x4d, 0x44, 0x23, 0x64, 0x3c, 0xe8, 0x0e,
       0x2a, 0x9a, 0xc9, 0x4f, 0xa5, 0x4c, 0xa4, 0x9f }
    },
    { "abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu",
     { 0x8e, 0x95, 0x9b, 0x75, 0xda, 0xe3, 0x13, 0xda,
       0x8c, 0xf4, 0xf7, 0x28, 0x14, 0xfc, 0x14, 0x3f,
       0x8f, 0x77, 0x79, 0xc6, 0xeb, 0x9f, 0x7f, 0xa1,
       0x72, 0x99, 0xae, 0xad, 0xb6, 0x88, 0x90, 0x18,
       0x50, 0x1d, 0x28, 0x9e, 0x49, 0x00, 0xf7, 0xe4,
       0x33, 0x1b, 0x99, 0xde, 0xc4, 0xb5, 0x43, 0x3a,
       0xc7, 0xd3, 0x29, 0xee, 0xb6, 0xdd, 0x26, 0x54,
       0x5e, 0x96, 0xe5, 0x5b, 0x87, 0x4b, 0xe9, 0x09 }
    },
  };

  int i;
  unsigned char tmp[64];
  hash_state md;

  for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) {
      sha512_init(&md);
      sha512_process(&md, (unsigned char *)tests[i].msg, (unsigned long)strlen(tests[i].msg));
      sha512_done(&md, tmp);
      if (compare_testvector(tmp, sizeof(tmp), tests[i].hash, sizeof(tests[i].hash), "SHA512", i)) {
         return CRYPT_FAIL_TESTVECTOR;
      }
  }
  return CRYPT_OK;
  #endif
}

#endif




/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
/* commit time: $Format:%ai$ */