view libtomcrypt/src/hashes/rmd128.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 rmd128.c
   RMD128 Hash function
*/

/* Implementation of LTC_RIPEMD-128 based on the source by Antoon Bosselaers, ESAT-COSIC
 *
 * This source has been radically overhauled to be portable and work within
 * the LibTomCrypt API by Tom St Denis
 */

#ifdef LTC_RIPEMD128

const struct ltc_hash_descriptor rmd128_desc =
{
    "rmd128",
    8,
    16,
    64,

    /* OID */
   { 1, 0, 10118, 3, 0, 50 },
   6,

    &rmd128_init,
    &rmd128_process,
    &rmd128_done,
    &rmd128_test,
    NULL
};

/* the four basic functions F(), G() and H() */
#define F(x, y, z)        ((x) ^ (y) ^ (z))
#define G(x, y, z)        (((x) & (y)) | (~(x) & (z)))
#define H(x, y, z)        (((x) | ~(y)) ^ (z))
#define I(x, y, z)        (((x) & (z)) | ((y) & ~(z)))

/* the eight basic operations FF() through III() */
#define FF(a, b, c, d, x, s)        \
      (a) += F((b), (c), (d)) + (x);\
      (a) = ROLc((a), (s));

#define GG(a, b, c, d, x, s)        \
      (a) += G((b), (c), (d)) + (x) + 0x5a827999UL;\
      (a) = ROLc((a), (s));

#define HH(a, b, c, d, x, s)        \
      (a) += H((b), (c), (d)) + (x) + 0x6ed9eba1UL;\
      (a) = ROLc((a), (s));

#define II(a, b, c, d, x, s)        \
      (a) += I((b), (c), (d)) + (x) + 0x8f1bbcdcUL;\
      (a) = ROLc((a), (s));

#define FFF(a, b, c, d, x, s)        \
      (a) += F((b), (c), (d)) + (x);\
      (a) = ROLc((a), (s));

#define GGG(a, b, c, d, x, s)        \
      (a) += G((b), (c), (d)) + (x) + 0x6d703ef3UL;\
      (a) = ROLc((a), (s));

#define HHH(a, b, c, d, x, s)        \
      (a) += H((b), (c), (d)) + (x) + 0x5c4dd124UL;\
      (a) = ROLc((a), (s));

#define III(a, b, c, d, x, s)        \
      (a) += I((b), (c), (d)) + (x) + 0x50a28be6UL;\
      (a) = ROLc((a), (s));

#ifdef LTC_CLEAN_STACK
static int _rmd128_compress(hash_state *md, unsigned char *buf)
#else
static int  rmd128_compress(hash_state *md, unsigned char *buf)
#endif
{
   ulong32 aa,bb,cc,dd,aaa,bbb,ccc,ddd,X[16];
   int i;

   /* load words X */
   for (i = 0; i < 16; i++){
      LOAD32L(X[i], buf + (4 * i));
   }

   /* load state */
   aa = aaa = md->rmd128.state[0];
   bb = bbb = md->rmd128.state[1];
   cc = ccc = md->rmd128.state[2];
   dd = ddd = md->rmd128.state[3];

   /* round 1 */
   FF(aa, bb, cc, dd, X[ 0], 11);
   FF(dd, aa, bb, cc, X[ 1], 14);
   FF(cc, dd, aa, bb, X[ 2], 15);
   FF(bb, cc, dd, aa, X[ 3], 12);
   FF(aa, bb, cc, dd, X[ 4],  5);
   FF(dd, aa, bb, cc, X[ 5],  8);
   FF(cc, dd, aa, bb, X[ 6],  7);
   FF(bb, cc, dd, aa, X[ 7],  9);
   FF(aa, bb, cc, dd, X[ 8], 11);
   FF(dd, aa, bb, cc, X[ 9], 13);
   FF(cc, dd, aa, bb, X[10], 14);
   FF(bb, cc, dd, aa, X[11], 15);
   FF(aa, bb, cc, dd, X[12],  6);
   FF(dd, aa, bb, cc, X[13],  7);
   FF(cc, dd, aa, bb, X[14],  9);
   FF(bb, cc, dd, aa, X[15],  8);

   /* round 2 */
   GG(aa, bb, cc, dd, X[ 7],  7);
   GG(dd, aa, bb, cc, X[ 4],  6);
   GG(cc, dd, aa, bb, X[13],  8);
   GG(bb, cc, dd, aa, X[ 1], 13);
   GG(aa, bb, cc, dd, X[10], 11);
   GG(dd, aa, bb, cc, X[ 6],  9);
   GG(cc, dd, aa, bb, X[15],  7);
   GG(bb, cc, dd, aa, X[ 3], 15);
   GG(aa, bb, cc, dd, X[12],  7);
   GG(dd, aa, bb, cc, X[ 0], 12);
   GG(cc, dd, aa, bb, X[ 9], 15);
   GG(bb, cc, dd, aa, X[ 5],  9);
   GG(aa, bb, cc, dd, X[ 2], 11);
   GG(dd, aa, bb, cc, X[14],  7);
   GG(cc, dd, aa, bb, X[11], 13);
   GG(bb, cc, dd, aa, X[ 8], 12);

   /* round 3 */
   HH(aa, bb, cc, dd, X[ 3], 11);
   HH(dd, aa, bb, cc, X[10], 13);
   HH(cc, dd, aa, bb, X[14],  6);
   HH(bb, cc, dd, aa, X[ 4],  7);
   HH(aa, bb, cc, dd, X[ 9], 14);
   HH(dd, aa, bb, cc, X[15],  9);
   HH(cc, dd, aa, bb, X[ 8], 13);
   HH(bb, cc, dd, aa, X[ 1], 15);
   HH(aa, bb, cc, dd, X[ 2], 14);
   HH(dd, aa, bb, cc, X[ 7],  8);
   HH(cc, dd, aa, bb, X[ 0], 13);
   HH(bb, cc, dd, aa, X[ 6],  6);
   HH(aa, bb, cc, dd, X[13],  5);
   HH(dd, aa, bb, cc, X[11], 12);
   HH(cc, dd, aa, bb, X[ 5],  7);
   HH(bb, cc, dd, aa, X[12],  5);

   /* round 4 */
   II(aa, bb, cc, dd, X[ 1], 11);
   II(dd, aa, bb, cc, X[ 9], 12);
   II(cc, dd, aa, bb, X[11], 14);
   II(bb, cc, dd, aa, X[10], 15);
   II(aa, bb, cc, dd, X[ 0], 14);
   II(dd, aa, bb, cc, X[ 8], 15);
   II(cc, dd, aa, bb, X[12],  9);
   II(bb, cc, dd, aa, X[ 4],  8);
   II(aa, bb, cc, dd, X[13],  9);
   II(dd, aa, bb, cc, X[ 3], 14);
   II(cc, dd, aa, bb, X[ 7],  5);
   II(bb, cc, dd, aa, X[15],  6);
   II(aa, bb, cc, dd, X[14],  8);
   II(dd, aa, bb, cc, X[ 5],  6);
   II(cc, dd, aa, bb, X[ 6],  5);
   II(bb, cc, dd, aa, X[ 2], 12);

   /* parallel round 1 */
   III(aaa, bbb, ccc, ddd, X[ 5],  8);
   III(ddd, aaa, bbb, ccc, X[14],  9);
   III(ccc, ddd, aaa, bbb, X[ 7],  9);
   III(bbb, ccc, ddd, aaa, X[ 0], 11);
   III(aaa, bbb, ccc, ddd, X[ 9], 13);
   III(ddd, aaa, bbb, ccc, X[ 2], 15);
   III(ccc, ddd, aaa, bbb, X[11], 15);
   III(bbb, ccc, ddd, aaa, X[ 4],  5);
   III(aaa, bbb, ccc, ddd, X[13],  7);
   III(ddd, aaa, bbb, ccc, X[ 6],  7);
   III(ccc, ddd, aaa, bbb, X[15],  8);
   III(bbb, ccc, ddd, aaa, X[ 8], 11);
   III(aaa, bbb, ccc, ddd, X[ 1], 14);
   III(ddd, aaa, bbb, ccc, X[10], 14);
   III(ccc, ddd, aaa, bbb, X[ 3], 12);
   III(bbb, ccc, ddd, aaa, X[12],  6);

   /* parallel round 2 */
   HHH(aaa, bbb, ccc, ddd, X[ 6],  9);
   HHH(ddd, aaa, bbb, ccc, X[11], 13);
   HHH(ccc, ddd, aaa, bbb, X[ 3], 15);
   HHH(bbb, ccc, ddd, aaa, X[ 7],  7);
   HHH(aaa, bbb, ccc, ddd, X[ 0], 12);
   HHH(ddd, aaa, bbb, ccc, X[13],  8);
   HHH(ccc, ddd, aaa, bbb, X[ 5],  9);
   HHH(bbb, ccc, ddd, aaa, X[10], 11);
   HHH(aaa, bbb, ccc, ddd, X[14],  7);
   HHH(ddd, aaa, bbb, ccc, X[15],  7);
   HHH(ccc, ddd, aaa, bbb, X[ 8], 12);
   HHH(bbb, ccc, ddd, aaa, X[12],  7);
   HHH(aaa, bbb, ccc, ddd, X[ 4],  6);
   HHH(ddd, aaa, bbb, ccc, X[ 9], 15);
   HHH(ccc, ddd, aaa, bbb, X[ 1], 13);
   HHH(bbb, ccc, ddd, aaa, X[ 2], 11);

   /* parallel round 3 */
   GGG(aaa, bbb, ccc, ddd, X[15],  9);
   GGG(ddd, aaa, bbb, ccc, X[ 5],  7);
   GGG(ccc, ddd, aaa, bbb, X[ 1], 15);
   GGG(bbb, ccc, ddd, aaa, X[ 3], 11);
   GGG(aaa, bbb, ccc, ddd, X[ 7],  8);
   GGG(ddd, aaa, bbb, ccc, X[14],  6);
   GGG(ccc, ddd, aaa, bbb, X[ 6],  6);
   GGG(bbb, ccc, ddd, aaa, X[ 9], 14);
   GGG(aaa, bbb, ccc, ddd, X[11], 12);
   GGG(ddd, aaa, bbb, ccc, X[ 8], 13);
   GGG(ccc, ddd, aaa, bbb, X[12],  5);
   GGG(bbb, ccc, ddd, aaa, X[ 2], 14);
   GGG(aaa, bbb, ccc, ddd, X[10], 13);
   GGG(ddd, aaa, bbb, ccc, X[ 0], 13);
   GGG(ccc, ddd, aaa, bbb, X[ 4],  7);
   GGG(bbb, ccc, ddd, aaa, X[13],  5);

   /* parallel round 4 */
   FFF(aaa, bbb, ccc, ddd, X[ 8], 15);
   FFF(ddd, aaa, bbb, ccc, X[ 6],  5);
   FFF(ccc, ddd, aaa, bbb, X[ 4],  8);
   FFF(bbb, ccc, ddd, aaa, X[ 1], 11);
   FFF(aaa, bbb, ccc, ddd, X[ 3], 14);
   FFF(ddd, aaa, bbb, ccc, X[11], 14);
   FFF(ccc, ddd, aaa, bbb, X[15],  6);
   FFF(bbb, ccc, ddd, aaa, X[ 0], 14);
   FFF(aaa, bbb, ccc, ddd, X[ 5],  6);
   FFF(ddd, aaa, bbb, ccc, X[12],  9);
   FFF(ccc, ddd, aaa, bbb, X[ 2], 12);
   FFF(bbb, ccc, ddd, aaa, X[13],  9);
   FFF(aaa, bbb, ccc, ddd, X[ 9], 12);
   FFF(ddd, aaa, bbb, ccc, X[ 7],  5);
   FFF(ccc, ddd, aaa, bbb, X[10], 15);
   FFF(bbb, ccc, ddd, aaa, X[14],  8);

   /* combine results */
   ddd += cc + md->rmd128.state[1];               /* final result for MDbuf[0] */
   md->rmd128.state[1] = md->rmd128.state[2] + dd + aaa;
   md->rmd128.state[2] = md->rmd128.state[3] + aa + bbb;
   md->rmd128.state[3] = md->rmd128.state[0] + bb + ccc;
   md->rmd128.state[0] = ddd;

   return CRYPT_OK;
}

#ifdef LTC_CLEAN_STACK
static int rmd128_compress(hash_state *md, unsigned char *buf)
{
   int err;
   err = _rmd128_compress(md, buf);
   burn_stack(sizeof(ulong32) * 24 + sizeof(int));
   return err;
}
#endif

/**
   Initialize the hash state
   @param md   The hash state you wish to initialize
   @return CRYPT_OK if successful
*/
int rmd128_init(hash_state * md)
{
   LTC_ARGCHK(md != NULL);
   md->rmd128.state[0] = 0x67452301UL;
   md->rmd128.state[1] = 0xefcdab89UL;
   md->rmd128.state[2] = 0x98badcfeUL;
   md->rmd128.state[3] = 0x10325476UL;
   md->rmd128.curlen   = 0;
   md->rmd128.length   = 0;
   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(rmd128_process, rmd128_compress, rmd128, 64)

/**
   Terminate the hash to get the digest
   @param md  The hash state
   @param out [out] The destination of the hash (16 bytes)
   @return CRYPT_OK if successful
*/
int rmd128_done(hash_state * md, unsigned char *out)
{
    int i;

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

    if (md->rmd128.curlen >= sizeof(md->rmd128.buf)) {
       return CRYPT_INVALID_ARG;
    }


    /* increase the length of the message */
    md->rmd128.length += md->rmd128.curlen * 8;

    /* append the '1' bit */
    md->rmd128.buf[md->rmd128.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->rmd128.curlen > 56) {
        while (md->rmd128.curlen < 64) {
            md->rmd128.buf[md->rmd128.curlen++] = (unsigned char)0;
        }
        rmd128_compress(md, md->rmd128.buf);
        md->rmd128.curlen = 0;
    }

    /* pad upto 56 bytes of zeroes */
    while (md->rmd128.curlen < 56) {
        md->rmd128.buf[md->rmd128.curlen++] = (unsigned char)0;
    }

    /* store length */
    STORE64L(md->rmd128.length, md->rmd128.buf+56);
    rmd128_compress(md, md->rmd128.buf);

    /* copy output */
    for (i = 0; i < 4; i++) {
        STORE32L(md->rmd128.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 rmd128_test(void)
{
#ifndef LTC_TEST
   return CRYPT_NOP;
#else
   static const struct {
        const char *msg;
        unsigned char hash[16];
   } tests[] = {
   { "",
     { 0xcd, 0xf2, 0x62, 0x13, 0xa1, 0x50, 0xdc, 0x3e,
       0xcb, 0x61, 0x0f, 0x18, 0xf6, 0xb3, 0x8b, 0x46 }
   },
   { "a",
     { 0x86, 0xbe, 0x7a, 0xfa, 0x33, 0x9d, 0x0f, 0xc7,
       0xcf, 0xc7, 0x85, 0xe7, 0x2f, 0x57, 0x8d, 0x33 }
   },
   { "abc",
     { 0xc1, 0x4a, 0x12, 0x19, 0x9c, 0x66, 0xe4, 0xba,
       0x84, 0x63, 0x6b, 0x0f, 0x69, 0x14, 0x4c, 0x77 }
   },
   { "message digest",
     { 0x9e, 0x32, 0x7b, 0x3d, 0x6e, 0x52, 0x30, 0x62,
       0xaf, 0xc1, 0x13, 0x2d, 0x7d, 0xf9, 0xd1, 0xb8 }
   },
   { "abcdefghijklmnopqrstuvwxyz",
     { 0xfd, 0x2a, 0xa6, 0x07, 0xf7, 0x1d, 0xc8, 0xf5,
       0x10, 0x71, 0x49, 0x22, 0xb3, 0x71, 0x83, 0x4e }
   },
   { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
     { 0xd1, 0xe9, 0x59, 0xeb, 0x17, 0x9c, 0x91, 0x1f,
       0xae, 0xa4, 0x62, 0x4c, 0x60, 0xc5, 0xc7, 0x02 }
   }
   };

   int i;
   unsigned char tmp[16];
   hash_state md;

   for (i = 0; i < (int)(sizeof(tests)/sizeof(tests[0])); i++) {
       rmd128_init(&md);
       rmd128_process(&md, (unsigned char *)tests[i].msg, strlen(tests[i].msg));
       rmd128_done(&md, tmp);
       if (compare_testvector(tmp, sizeof(tmp), tests[i].hash, sizeof(tests[i].hash), "RIPEMD128", i)) {
          return CRYPT_FAIL_TESTVECTOR;
       }
   }
   return CRYPT_OK;
#endif
}

#endif


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