C++程序  |  595行  |  12.63 KB

/*****************************************************************************/
// Copyright 2006-2007 Adobe Systems Incorporated
// All Rights Reserved.
//
// NOTICE:  Adobe permits you to use, modify, and distribute this file in
// accordance with the terms of the Adobe license agreement accompanying it.
/*****************************************************************************/

/* $Id: //mondo/dng_sdk_1_4/dng_sdk/source/dng_fingerprint.cpp#3 $ */ 
/* $DateTime: 2012/07/11 10:36:56 $ */
/* $Change: 838485 $ */
/* $Author: tknoll $ */

/*****************************************************************************/

#include "dng_fingerprint.h"

#include "dng_assertions.h"
#include "dng_flags.h"

/*****************************************************************************/

dng_fingerprint::dng_fingerprint ()
	{
	
	for (uint32 j = 0; j < 16; j++)
		{
		
		data [j] = 0;
		
		}
		
	}

/*****************************************************************************/

bool dng_fingerprint::IsNull () const
	{
	
	for (uint32 j = 0; j < 16; j++)
		{
		
		if (data [j] != 0)
			{
			
			return false;
			
			}
			
		}
		
	return true;
	
	}

/*****************************************************************************/

bool dng_fingerprint::operator== (const dng_fingerprint &print) const
	{
	
	for (uint32 j = 0; j < 16; j++)
		{
		
		if (data [j] != print.data [j])
			{
			
			return false;
			
			}
			
		}
		
	return true;
	
	}
		
/******************************************************************************/

uint32 dng_fingerprint::Collapse32 () const
	{
	
	uint32 x = 0;
	
	for (uint32 j = 0; j < 4; j++)
		{
		
		uint32 y = 0;
		
		for (uint32 k = 0; k < 4; k++)
			{
			
			y = (y << 8) + (uint32) data [j * 4 + k];
			
			}
			
		x = x ^ y;
		
		}
		
	return x;
	
	}

/******************************************************************************/

static char NumToHexChar (unsigned int c)
	{

	if (c < 10)
		{
		return (char) ('0' + c);
		}

	else
		{
		return (char) ('A' + c - 10);
		}

	}

/*****************************************************************************/

void dng_fingerprint::ToUtf8HexString (char resultStr [2 * kDNGFingerprintSize + 1]) const
	{
	
	for (size_t i = 0; i < kDNGFingerprintSize; i++)
		{
		
		unsigned char c = data [i];

		resultStr [i * 2] = NumToHexChar (c >> 4);
		resultStr [i * 2 + 1] = NumToHexChar (c & 15);
		
		}
	
	resultStr [kDNGFingerprintSize * 2] = '\0';

	}

/******************************************************************************/

static int HexCharToNum (char hexChar)
	{
	
	if (hexChar >= '0' && hexChar <= '9')
		{
		return hexChar - '0';
		}

	else if (hexChar >= 'A' && hexChar <= 'F')
		{
		return hexChar - 'A' + 10;
		}

	else if (hexChar >= 'a' && hexChar <= 'f')
		{
		return hexChar - 'a' + 10;
		}
	
	return -1;
	
	}

/*****************************************************************************/

bool dng_fingerprint::FromUtf8HexString (const char inputStr [2 * kDNGFingerprintSize + 1])
	{
	
	for (size_t i = 0; i < kDNGFingerprintSize; i++)
		{
		
		int highNibble = HexCharToNum (inputStr [i * 2]);

		if (highNibble < 0)
			{
			return false;
			}
		
		int lowNibble = HexCharToNum (inputStr [i * 2 + 1]);

		if (lowNibble < 0)
			{
			return false;
			}

		data [i] = (uint8) ((highNibble << 4) + lowNibble);
		
		}
	
	return true;

	}

/******************************************************************************/

// Derived from the RSA Data Security, Inc. MD5 Message-Digest Algorithm

// 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.

/******************************************************************************/

dng_md5_printer::dng_md5_printer ()

	:	final  (false)
	,	result ()
	
	{
	
	Reset ();
	
	}
								
/******************************************************************************/

void dng_md5_printer::Reset ()
	{
	
	// No bits processed yet.
	
	count [0] = 0;
	count [1] = 0;

	// Load magic initialization constants.

	state [0] = 0x67452301;
	state [1] = 0xefcdab89;
	state [2] = 0x98badcfe;
	state [3] = 0x10325476;

	// Not finalized yet.
	
	final = false;
	
	}

/******************************************************************************/

void dng_md5_printer::Process (const void *data,
					  		   uint32 inputLen)
	{
	
	DNG_ASSERT (!final, "Fingerprint already finalized!");
	
	const uint8 *input = (const uint8 *) data;
	
	// Compute number of bytes mod 64
	
	uint32 index = (count [0] >> 3) & 0x3F;

	// Update number of bits
	
	if ((count [0] += inputLen << 3) < (inputLen << 3))
		{
		count [1]++;
		}
		
	count [1] += inputLen >> 29;

	// Transform as many times as possible.
	
	uint32 i = 0;

	uint32 partLen = 64 - index;

	if (inputLen >= partLen)
		{
		
		memcpy (&buffer [index],
				input,
				partLen);
				
		MD5Transform (state, buffer);

		for (i = partLen; i + 63 < inputLen; i += 64)
			{
			
			MD5Transform (state, &input [i]);
			
			}

		index = 0;
		
		}
		
	// Buffer remaining input
	
	memcpy (&buffer [index],
			&input [i],
			inputLen - i);
	
	}
		
/******************************************************************************/

const dng_fingerprint & dng_md5_printer::Result ()
	{
	
	if (!final)
		{
		
		static uint8 PADDING [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
			};

		// Save number of bits
		
		uint8 bits [8];

		Encode (bits, count, 8);

		// Pad out to 56 mod 64.
		
		uint32 index = (count [0] >> 3) & 0x3f;
		
		uint32 padLen = (index < 56) ? (56 - index) : (120 - index);
		
		Process (PADDING, padLen);

		// Append length (before padding)

		Process (bits, 8);

		// Store state in digest
		
		Encode (result.data, state, 16);

		// We are now finalized.
		
		final = true;
		
		}
	
	return result;

	}

/******************************************************************************/

// Encodes input (uint32) into output (uint8). Assumes len is
// a multiple of 4.

void dng_md5_printer::Encode (uint8 *output,
							  const uint32 *input,
							  uint32 len)
	{

	uint32 i, j;
	
	for (i = 0, j = 0; j < len; i++, j += 4)
		{
		output [j  ] = (uint8) ((input [i]      ) & 0xff);
		output [j+1] = (uint8) ((input [i] >>  8) & 0xff);
		output [j+2] = (uint8) ((input [i] >> 16) & 0xff);
		output [j+3] = (uint8) ((input [i] >> 24) & 0xff);
		}

	}

/******************************************************************************/

// Decodes input (uint8) into output (uint32). Assumes len is
// a multiple of 4.

void dng_md5_printer::Decode (uint32 *output,
							  const uint8 *input,
							  uint32 len)
	{
	
	// Check for non-aligned case.
	
	if (((uintptr) input) & 3)
		{

		uint32 i, j;
	
		for (i = 0, j = 0; j < len; i++, j += 4)
			{
			
	 		output [i] = (((uint32) input [j  ])      ) |
	 					 (((uint32) input [j+1]) <<  8) |
	   					 (((uint32) input [j+2]) << 16) |
	   					 (((uint32) input [j+3]) << 24);
	   
	   		}
	   		
	   	}
	   	
	// Else use optimized code for aligned case.
	   	
	else
		{
		
		len = len >> 2;
		
		const uint32 *sPtr = (const uint32 *) input;
		
		uint32 *dPtr = output;
		
		while (len--)
			{
			
			#if qDNGBigEndian
			
			uint32 data = *(sPtr++);
			
			data = (data >> 24) |
				   ((data >> 8) & 0x0000FF00) |
				   ((data << 8) & 0x00FF0000) |
				   (data << 24);
				   
			*(dPtr++) = data;
			
			#else
			
			*(dPtr++) = *(sPtr++);
			
			#endif

			}
				
		}
   
	}

/******************************************************************************/

// MD5 basic transformation. Transforms state based on block.

#if defined(__clang__) && defined(__has_attribute)
#if __has_attribute(no_sanitize)
__attribute__((no_sanitize("unsigned-integer-overflow")))
#endif
#endif
void dng_md5_printer::MD5Transform (uint32 state [4],
								    const uint8 block [64])
	{
	
	enum
		{
		S11 = 7,
		S12 = 12,
		S13 = 17,
		S14 = 22,
		S21 = 5,
		S22 = 9,
		S23 = 14,
		S24 = 20,
		S31 = 4,
		S32 = 11,
		S33 = 16,
		S34 = 23,
		S41 = 6,
		S42 = 10,
		S43 = 15,
		S44 = 21
		};
		
	#if qDNGBigEndian

	uint32 x [16];

	Decode (x, block, 64);
	
	#else

	uint32 temp [16];

	const uint32 *x;
	
	if (((uintptr) block) & 3)
		{
		
		Decode (temp, block, 64);
		
		x = temp;
		
		}
		
	else
		x = (const uint32 *) block;
		
	#endif

	uint32 a = state [0];
	uint32 b = state [1];
	uint32 c = state [2];
	uint32 d = state [3];
	
	/* 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 */

	state [0] += a;
	state [1] += b;
	state [2] += c;
	state [3] += d;

	}

/*****************************************************************************/

// End of RSA Data Security, Inc. derived code.

/*****************************************************************************/