/* Web Polygraph http://www.web-polygraph.org/
* (C) 2003-2006 The Measurement Factory
* Licensed under the Apache License, Version 2.0 */
#include "xstd/xstd.h"
#include "xstd/h/iomanip.h"
#include "xstd/h/string.h"
#include "xstd/Assert.h"
#include "xstd/Checksum.h"
bool Checksum::equal(const Checksum &s) const {
Assert(set() && s.set());
return memcmp(theDigest, s.theDigest, sizeof(theDigest)) == 0;
}
ostream &Checksum::print(ostream &os) const {
if (set()) {
const ios_fmtflags flags = os.flags();
const char fill = os.fill('0');
os << hex << setfill('0');
for (int i = 0; i < size(); ++i)
os << setw(2) << (unsigned int)theDigest[i];
os.fill(fill);
os.flags(flags);
return os;
}
return os << "<none>";
}
/*
* Derived from RFC 1321, Appendix 3. Copyright (C) 1991-2, RSA Data
* Security, Inc. Created 1991. All rights reserved. License to copy and
* use this software is granted provided that it is identified as the "RSA
* Data Security, Inc. MD5 Message-Digest Algorithm" in all material
* mentioning or referencing this software or this function. License is
* also granted to make and use derivative works provided that such works
* are identified as "derived from the RSA Data Security, Inc. MD5
* Message-Digest Algorithm" in all material mentioning or referencing the
* derived work. RSA Data Security, Inc. makes no representations
* concerning either the merchantability of this software or the
* suitability of this software for any particular purpose. It is provided
* "as is" without express or implied warranty of any kind. These notices
* must be retained in any copies of any part of this documentation and/or
* software.
*/
#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21
const unsigned char ChecksumAlg::ThePadding[64] = {
0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))
// ROTATE_LEFT rotates x left n bits.
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
// FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
// Rotation is separate from addition to prevent recomputation.
#define FF(a, b, c, d, x, s, ac) { \
(a) += F ((b), (c), (d)) + (x) + (unsigned int)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define GG(a, b, c, d, x, s, ac) { \
(a) += G ((b), (c), (d)) + (x) + (unsigned int)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define HH(a, b, c, d, x, s, ac) { \
(a) += H ((b), (c), (d)) + (x) + (unsigned int)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define II(a, b, c, d, x, s, ac) { \
(a) += I ((b), (c), (d)) + (x) + (unsigned int)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
ChecksumAlg::ChecksumAlg() {
reset();
}
void ChecksumAlg::reset() {
theCounts[0] = theCounts[1] = 0;
theState[0] = 0x67452301;
theState[1] = 0xefcdab89;
theState[2] = 0x98badcfe;
theState[3] = 0x10325476;
theSum.reset();
}
// MD5 block update operation. Continues an MD5 message-digest
// operation, processing another message block, and updating the context.
void ChecksumAlg::update(const unsigned char *input, const unsigned inputLen) {
Assert(!theSum.set());
// Compute number of bytes mod 64
unsigned int index =
(unsigned int)((theCounts[0] >> 3) & 0x3F);
// Update number of bits
if ((theCounts[0] += ((unsigned int)inputLen << 3)) < ((unsigned int)inputLen << 3))
theCounts[1]++;
theCounts[1] += ((unsigned int)inputLen >> 29);
const unsigned int partLen = 64 - index;
// transform as many times as possible.
unsigned int i = 0;
if (inputLen >= partLen) {
memcpy(&theBuffer[index], input, partLen);
transform(theBuffer);
for (i = partLen; i + 63 < inputLen; i += 64)
transform(&input[i]);
index = 0;
}
// Buffer remaining input
memcpy(&theBuffer[index], &input[i], inputLen-i);
}
void ChecksumAlg::update(const char *buf, Size size) {
update((const unsigned char *)buf, (unsigned int)size);
}
// MD5 finalization. Ends an MD5 message-digest operation, writing the
// the message digest and zeroizing the context.
void ChecksumAlg::final() {
unsigned char bits[8];
unsigned int index, padLen;
// save number of bits
encode(bits, theCounts, 8);
// pad out to 56 mod 64.
index = (unsigned int)((theCounts[0] >> 3) & 0x3f);
padLen = index < 56 ? (56 - index) : (120 - index);
update(ThePadding, padLen);
// append length (before padding)
update(bits, 8);
// store state in digest
encode(theSum.theDigest, theState, sizeof(theSum.theDigest));
theSum.isSet = true;
// zeroize sensitive information
memset(theState, 0, sizeof(theState));
memset(theCounts, 0, sizeof(theCounts));
memset(theBuffer, 0, sizeof(theBuffer));
}
// MD5 basic transformation. Transforms state based on block.
void ChecksumAlg::transform(const unsigned char block[64]) {
unsigned int a = theState[0];
unsigned int b = theState[1];
unsigned int c = theState[2];
unsigned int d = theState[3];
unsigned int x[16];
decode(x, block, 64);
/* Round 1 */
FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
/* Round 2 */
GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */
GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
/* Round 3 */
HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
/* Round 4 */
II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
theState[0] += a;
theState[1] += b;
theState[2] += c;
theState[3] += d;
// Zeroize sensitive information.
memset(x, 0, sizeof(x));
}
// encodes input (unsigned int) into output (unsigned char)
// assumes len is a multiple of 4
void ChecksumAlg::encode(unsigned char *output, const unsigned int *input, unsigned int len) {
unsigned int i, j;
for (i = 0, j = 0; j < len; i++, j += 4) {
output[j] = (unsigned char)(input[i] & 0xff);
output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
}
}
// decodes input (unsigned char) into output (unsigned int)
// assumes len is a multiple of 4
void ChecksumAlg::decode(unsigned int *output, const unsigned char *input, unsigned int len) {
unsigned int i, j;
for (i = 0, j = 0; j < len; i++, j += 4) {
output[i] = ((unsigned int)input[j]) | (((unsigned int)input[j+1]) << 8) |
(((unsigned int)input[j+2]) << 16) | (((unsigned int)input[j+3]) << 24);
}
}
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