libclamav/sha256.c
4e46d65d
 /*-
  * Copyright (c) 2001-2003 Allan Saddi <allan@saddi.com>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY ALLAN SADDI AND HIS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL ALLAN SADDI OR HIS CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
  * $Id: sha256.c 680 2003-07-25 21:57:49Z asaddi $
  */
 
 /*
  * Define WORDS_BIGENDIAN if compiling on a big-endian architecture.
  *
  * Define SHA256_TEST to test the implementation using the NIST's
  * sample messages. The output should be:
  *
  *   ba7816bf 8f01cfea 414140de 5dae2223 b00361a3 96177a9c b410ff61 f20015ad
  *   248d6a61 d20638b8 e5c02693 0c3e6039 a33ce459 64ff2167 f6ecedd4 19db06c1
  *   cdc76e5c 9914fb92 81a1c7e2 84d73e67 f1809a48 a497200e 046d39cc c7112cd0
  */
 
 #ifdef HAVE_CONFIG_H
 #include "clamav-config.h"
 #endif /* HAVE_CONFIG_H */
 
 #if HAVE_INTTYPES_H
 # include <inttypes.h>
 #else
 # if HAVE_STDINT_H
 #  include <stdint.h>
 # endif
 #endif
 
 #include <string.h>
 
 #include "sha256.h"
 
 #ifndef lint
 static const char rcsid[] =
 	"$Id: sha256.c 680 2003-07-25 21:57:49Z asaddi $";
 #endif /* !lint */
 
 #define ROTL(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
 #define ROTR(x, n) (((x) >> (n)) | ((x) << (32 - (n))))
 
 #define Ch(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
 #define Maj(x, y, z) (((x) & ((y) | (z))) | ((y) & (z)))
 #define SIGMA0(x) (ROTR((x), 2) ^ ROTR((x), 13) ^ ROTR((x), 22))
 #define SIGMA1(x) (ROTR((x), 6) ^ ROTR((x), 11) ^ ROTR((x), 25))
 #define sigma0(x) (ROTR((x), 7) ^ ROTR((x), 18) ^ ((x) >> 3))
 #define sigma1(x) (ROTR((x), 17) ^ ROTR((x), 19) ^ ((x) >> 10))
 
 #define DO_ROUND() { \
   t1 = h + SIGMA1(e) + Ch(e, f, g) + *(Kp++) + *(W++); \
   t2 = SIGMA0(a) + Maj(a, b, c); \
   h = g; \
   g = f; \
   f = e; \
   e = d + t1; \
   d = c; \
   c = b; \
   b = a; \
   a = t1 + t2; \
 }
 
 static const uint32_t K[64] = {
   0x428a2f98L, 0x71374491L, 0xb5c0fbcfL, 0xe9b5dba5L,
   0x3956c25bL, 0x59f111f1L, 0x923f82a4L, 0xab1c5ed5L,
   0xd807aa98L, 0x12835b01L, 0x243185beL, 0x550c7dc3L,
   0x72be5d74L, 0x80deb1feL, 0x9bdc06a7L, 0xc19bf174L,
   0xe49b69c1L, 0xefbe4786L, 0x0fc19dc6L, 0x240ca1ccL,
   0x2de92c6fL, 0x4a7484aaL, 0x5cb0a9dcL, 0x76f988daL,
   0x983e5152L, 0xa831c66dL, 0xb00327c8L, 0xbf597fc7L,
   0xc6e00bf3L, 0xd5a79147L, 0x06ca6351L, 0x14292967L,
   0x27b70a85L, 0x2e1b2138L, 0x4d2c6dfcL, 0x53380d13L,
   0x650a7354L, 0x766a0abbL, 0x81c2c92eL, 0x92722c85L,
   0xa2bfe8a1L, 0xa81a664bL, 0xc24b8b70L, 0xc76c51a3L,
   0xd192e819L, 0xd6990624L, 0xf40e3585L, 0x106aa070L,
   0x19a4c116L, 0x1e376c08L, 0x2748774cL, 0x34b0bcb5L,
   0x391c0cb3L, 0x4ed8aa4aL, 0x5b9cca4fL, 0x682e6ff3L,
   0x748f82eeL, 0x78a5636fL, 0x84c87814L, 0x8cc70208L,
   0x90befffaL, 0xa4506cebL, 0xbef9a3f7L, 0xc67178f2L
 };
 
 #ifndef RUNTIME_ENDIAN
 
 #if WORDS_BIGENDIAN == 1 
 
 #define BYTESWAP(x) (x)
 #define BYTESWAP64(x) (x)
 
 #else /* WORDS_BIGENDIAN */
 
 #define BYTESWAP(x) ((ROTR((x), 8) & 0xff00ff00L) | \
 		     (ROTL((x), 8) & 0x00ff00ffL))
 #define BYTESWAP64(x) _byteswap64(x)
 
 static inline uint64_t _byteswap64(uint64_t x)
 {
   uint32_t a = x >> 32;
   uint32_t b = (uint32_t) x;
   return ((uint64_t) BYTESWAP(b) << 32) | (uint64_t) BYTESWAP(a);
 }
 
 #endif /* WORDS_BIGENDIAN */
 
 #else /* !RUNTIME_ENDIAN */
 
 #define BYTESWAP(x) _byteswap(sc->littleEndian, x)
 #define BYTESWAP64(x) _byteswap64(sc->littleEndian, x)
 
 #define _BYTESWAP(x) ((ROTR((x), 8) & 0xff00ff00L) | \
 		      (ROTL((x), 8) & 0x00ff00ffL))
 #define _BYTESWAP64(x) __byteswap64(x)
 
 static inline uint64_t __byteswap64(uint64_t x)
 {
   uint32_t a = x >> 32;
   uint32_t b = (uint32_t) x;
   return ((uint64_t) _BYTESWAP(b) << 32) | (uint64_t) _BYTESWAP(a);
 }
 
 static inline uint32_t _byteswap(int littleEndian, uint32_t x)
 {
   if (!littleEndian)
     return x;
   else
     return _BYTESWAP(x);
 }
 
 static inline uint64_t _byteswap64(int littleEndian, uint64_t x)
 {
   if (!littleEndian)
     return x;
   else
     return _BYTESWAP64(x);
 }
 
 static inline void setEndian(int *littleEndianp)
 {
   union {
     uint32_t w;
     uint8_t b[4];
   } endian;
 
   endian.w = 1L;
   *littleEndianp = endian.b[0] != 0;
 }
 
 #endif /* !RUNTIME_ENDIAN */
 
 static const uint8_t padding[64] = {
   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, 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
 };
 
 void
 sha256_init (SHA256_CTX *sc)
 {
 #ifdef RUNTIME_ENDIAN
   setEndian (&sc->littleEndian);
 #endif /* RUNTIME_ENDIAN */
 
   sc->totalLength = 0LL;
   sc->hash[0] = 0x6a09e667L;
   sc->hash[1] = 0xbb67ae85L;
   sc->hash[2] = 0x3c6ef372L;
   sc->hash[3] = 0xa54ff53aL;
   sc->hash[4] = 0x510e527fL;
   sc->hash[5] = 0x9b05688cL;
   sc->hash[6] = 0x1f83d9abL;
   sc->hash[7] = 0x5be0cd19L;
   sc->bufferLength = 0L;
 }
 
 static void
 burnStack (int size)
 {
   char buf[128];
 
   memset (buf, 0, sizeof (buf));
   size -= sizeof (buf);
   if (size > 0)
     burnStack (size);
 }
 
 static void
 SHA256Guts (SHA256_CTX *sc, const uint32_t *cbuf)
 {
   uint32_t buf[64];
   uint32_t *W, *W2, *W7, *W15, *W16;
   uint32_t a, b, c, d, e, f, g, h;
   uint32_t t1, t2;
   const uint32_t *Kp;
   int i;
 
   W = buf;
 
   for (i = 15; i >= 0; i--) {
     *(W++) = BYTESWAP(*cbuf);
     cbuf++;
   }
 
   W16 = &buf[0];
   W15 = &buf[1];
   W7 = &buf[9];
   W2 = &buf[14];
 
   for (i = 47; i >= 0; i--) {
     *(W++) = sigma1(*W2) + *(W7++) + sigma0(*W15) + *(W16++);
     W2++;
     W15++;
   }
 
   a = sc->hash[0];
   b = sc->hash[1];
   c = sc->hash[2];
   d = sc->hash[3];
   e = sc->hash[4];
   f = sc->hash[5];
   g = sc->hash[6];
   h = sc->hash[7];
 
   Kp = K;
   W = buf;
 
 #ifndef SHA256_UNROLL
 #define SHA256_UNROLL 1
 #endif /* !SHA256_UNROLL */
 
 #if SHA256_UNROLL == 1
   for (i = 63; i >= 0; i--)
     DO_ROUND();
 #elif SHA256_UNROLL == 2
   for (i = 31; i >= 0; i--) {
     DO_ROUND(); DO_ROUND();
   }
 #elif SHA256_UNROLL == 4
   for (i = 15; i >= 0; i--) {
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   }
 #elif SHA256_UNROLL == 8
   for (i = 7; i >= 0; i--) {
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   }
 #elif SHA256_UNROLL == 16
   for (i = 3; i >= 0; i--) {
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   }
 #elif SHA256_UNROLL == 32
   for (i = 1; i >= 0; i--) {
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
     DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   }
 #elif SHA256_UNROLL == 64
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
   DO_ROUND(); DO_ROUND(); DO_ROUND(); DO_ROUND();
 #else
 #error "SHA256_UNROLL must be 1, 2, 4, 8, 16, 32, or 64!"
 #endif
 
   sc->hash[0] += a;
   sc->hash[1] += b;
   sc->hash[2] += c;
   sc->hash[3] += d;
   sc->hash[4] += e;
   sc->hash[5] += f;
   sc->hash[6] += g;
   sc->hash[7] += h;
 }
 
 void
 sha256_update (SHA256_CTX *sc, const void *vdata, uint32_t len)
 {
   const uint8_t *data = vdata;
   uint32_t bufferBytesLeft;
   uint32_t bytesToCopy;
   int needBurn = 0;
 
 #ifdef SHA256_FAST_COPY
   if (sc->bufferLength) {
     bufferBytesLeft = 64L - sc->bufferLength;
 
     bytesToCopy = bufferBytesLeft;
     if (bytesToCopy > len)
       bytesToCopy = len;
 
     memcpy (&sc->buffer.bytes[sc->bufferLength], data, bytesToCopy);
 
     sc->totalLength += bytesToCopy * 8L;
 
     sc->bufferLength += bytesToCopy;
     data += bytesToCopy;
     len -= bytesToCopy;
 
     if (sc->bufferLength == 64L) {
       SHA256Guts (sc, sc->buffer.words);
       needBurn = 1;
       sc->bufferLength = 0L;
     }
   }
 
   while (len > 63L) {
     sc->totalLength += 512L;
 
     SHA256Guts (sc, data);
     needBurn = 1;
 
     data += 64L;
     len -= 64L;
   }
 
   if (len) {
     memcpy (&sc->buffer.bytes[sc->bufferLength], data, len);
 
     sc->totalLength += len * 8L;
 
     sc->bufferLength += len;
   }
 #else /* SHA256_FAST_COPY */
   while (len) {
     bufferBytesLeft = 64L - sc->bufferLength;
 
     bytesToCopy = bufferBytesLeft;
     if (bytesToCopy > len)
       bytesToCopy = len;
 
     memcpy (&sc->buffer.bytes[sc->bufferLength], data, bytesToCopy);
 
     sc->totalLength += bytesToCopy * 8L;
 
     sc->bufferLength += bytesToCopy;
     data += bytesToCopy;
     len -= bytesToCopy;
 
     if (sc->bufferLength == 64L) {
       SHA256Guts (sc, sc->buffer.words);
       needBurn = 1;
       sc->bufferLength = 0L;
     }
   }
 #endif /* SHA256_FAST_COPY */
 
   if (needBurn)
     burnStack (sizeof (uint32_t[74]) + sizeof (uint32_t *[6]) + sizeof (int));
 }
 
 void
 sha256_final (SHA256_CTX *sc, uint8_t hash[SHA256_HASH_SIZE])
 {
   uint32_t bytesToPad;
   uint64_t lengthPad;
   int i;
 
   bytesToPad = 120L - sc->bufferLength;
   if (bytesToPad > 64L)
     bytesToPad -= 64L;
 
   lengthPad = BYTESWAP64(sc->totalLength);
 
   sha256_update (sc, padding, bytesToPad);
   sha256_update (sc, &lengthPad, 8L);
 
   if (hash) {
     for (i = 0; i < SHA256_HASH_WORDS; i++) {
 #ifdef SHA256_FAST_COPY
       *((uint32_t *) hash) = BYTESWAP(sc->hash[i]);
 #else /* SHA256_FAST_COPY */
       hash[0] = (uint8_t) (sc->hash[i] >> 24);
       hash[1] = (uint8_t) (sc->hash[i] >> 16);
       hash[2] = (uint8_t) (sc->hash[i] >> 8);
       hash[3] = (uint8_t) sc->hash[i];
 #endif /* SHA256_FAST_COPY */
       hash += 4;
     }
   }
 }
 
 #ifdef SHA256_TEST
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 int
 main (int argc, char *argv[])
 {
   SHA256_CTX foo;
   uint8_t hash[SHA256_HASH_SIZE];
   char buf[1000];
   int i;
 
   sha256_init (&foo);
   sha256_update (&foo, "abc", 3);
   sha256_final (&foo, hash);
 
   for (i = 0; i < SHA256_HASH_SIZE;) {
     printf ("%02x", hash[i++]);
     if (!(i % 4))
       printf (" ");
   }
   printf ("\n");
 
   sha256_init (&foo);
   sha256_update (&foo,
 		"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
 		56);
   sha256_final (&foo, hash);
 
   for (i = 0; i < SHA256_HASH_SIZE;) {
     printf ("%02x", hash[i++]);
     if (!(i % 4))
       printf (" ");
   }
   printf ("\n");
 
   sha256_init (&foo);
   memset (buf, 'a', sizeof (buf));
   for (i = 0; i < 1000; i++)
     sha256_update (&foo, buf, sizeof (buf));
   sha256_final (&foo, hash);
 
   for (i = 0; i < SHA256_HASH_SIZE;) {
     printf ("%02x", hash[i++]);
     if (!(i % 4))
       printf (" ");
   }
   printf ("\n");
 
   exit (0);
 }
 
 #endif /* SHA256_TEST */