mirror of
https://github.com/qpdf/qpdf.git
synced 2024-11-01 03:12:29 +00:00
430 lines
12 KiB
C++
430 lines
12 KiB
C++
// This file implements a class for computation of MD5 checksums.
|
|
// It is derived from the reference algorithm for MD5 as given in
|
|
// RFC 1321. The original copyright notice is as follows:
|
|
//
|
|
/////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// 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.
|
|
//
|
|
/////////////////////////////////////////////////////////////////////////
|
|
|
|
#include <qpdf/MD5.hh>
|
|
#include <qpdf/QUtil.hh>
|
|
|
|
#include <stdio.h>
|
|
#include <memory.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
|
|
int const S11 = 7;
|
|
int const S12 = 12;
|
|
int const S13 = 17;
|
|
int const S14 = 22;
|
|
int const S21 = 5;
|
|
int const S22 = 9;
|
|
int const S23 = 14;
|
|
int const S24 = 20;
|
|
int const S31 = 4;
|
|
int const S32 = 11;
|
|
int const S33 = 16;
|
|
int const S34 = 23;
|
|
int const S41 = 6;
|
|
int const S42 = 10;
|
|
int const S43 = 15;
|
|
int const S44 = 21;
|
|
|
|
static unsigned char 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
|
|
};
|
|
|
|
// F, G, H and I are basic MD5 functions.
|
|
#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) + static_cast<UINT4>(ac); \
|
|
(a) = ROTATE_LEFT ((a), (s)); \
|
|
(a) += (b); \
|
|
}
|
|
#define GG(a, b, c, d, x, s, ac) { \
|
|
(a) += G ((b), (c), (d)) + (x) + static_cast<UINT4>(ac); \
|
|
(a) = ROTATE_LEFT ((a), (s)); \
|
|
(a) += (b); \
|
|
}
|
|
#define HH(a, b, c, d, x, s, ac) { \
|
|
(a) += H ((b), (c), (d)) + (x) + static_cast<UINT4>(ac); \
|
|
(a) = ROTATE_LEFT ((a), (s)); \
|
|
(a) += (b); \
|
|
}
|
|
#define II(a, b, c, d, x, s, ac) { \
|
|
(a) += I ((b), (c), (d)) + (x) + static_cast<UINT4>(ac); \
|
|
(a) = ROTATE_LEFT ((a), (s)); \
|
|
(a) += (b); \
|
|
}
|
|
|
|
// MD5 initialization. Begins an MD5 operation, writing a new context.
|
|
void MD5::init()
|
|
{
|
|
count[0] = count[1] = 0;
|
|
// Load magic initialization constants.
|
|
state[0] = 0x67452301;
|
|
state[1] = 0xefcdab89;
|
|
state[2] = 0x98badcfe;
|
|
state[3] = 0x10325476;
|
|
|
|
finalized = false;
|
|
memset(digest_val, 0, sizeof(digest_val));
|
|
}
|
|
|
|
// MD5 block update operation. Continues an MD5 message-digest
|
|
// operation, processing another message block, and updating the
|
|
// context.
|
|
|
|
void MD5::update(unsigned char *input,
|
|
unsigned int inputLen)
|
|
{
|
|
unsigned int i, index, partLen;
|
|
|
|
// Compute number of bytes mod 64
|
|
index = static_cast<unsigned int>((count[0] >> 3) & 0x3f);
|
|
|
|
// Update number of bits
|
|
if ((count[0] += (static_cast<UINT4>(inputLen) << 3)) <
|
|
(static_cast<UINT4>(inputLen) << 3))
|
|
count[1]++;
|
|
count[1] += (static_cast<UINT4>(inputLen) >> 29);
|
|
|
|
partLen = 64 - index;
|
|
|
|
// Transform as many times as possible.
|
|
|
|
if (inputLen >= partLen) {
|
|
memcpy(&buffer[index], input, partLen);
|
|
transform(state, buffer);
|
|
|
|
for (i = partLen; i + 63 < inputLen; i += 64)
|
|
transform(state, &input[i]);
|
|
|
|
index = 0;
|
|
}
|
|
else
|
|
i = 0;
|
|
|
|
// Buffer remaining input
|
|
memcpy(&buffer[index], &input[i], inputLen-i);
|
|
}
|
|
|
|
// MD5 finalization. Ends an MD5 message-digest operation, writing the
|
|
// the message digest and zeroizing the context.
|
|
void MD5::final()
|
|
{
|
|
if (finalized)
|
|
{
|
|
return;
|
|
}
|
|
|
|
unsigned char bits[8];
|
|
unsigned int index, padLen;
|
|
|
|
// Save number of bits
|
|
encode(bits, count, 8);
|
|
|
|
// Pad out to 56 mod 64.
|
|
|
|
index = static_cast<unsigned int>((count[0] >> 3) & 0x3f);
|
|
padLen = (index < 56) ? (56 - index) : (120 - index);
|
|
update(PADDING, padLen);
|
|
|
|
// Append length (before padding)
|
|
update(bits, 8);
|
|
// Store state in digest_val
|
|
encode(digest_val, state, 16);
|
|
|
|
// Zeroize sensitive information.
|
|
memset(state, 0, sizeof(state));
|
|
memset(count, 0, sizeof(count));
|
|
memset(buffer, 0, sizeof(buffer));
|
|
|
|
finalized = true;
|
|
}
|
|
|
|
// MD5 basic transformation. Transforms state based on block.
|
|
void MD5::transform(UINT4 state[4], unsigned char block[64])
|
|
{
|
|
UINT4 a = state[0], b = state[1], c = state[2], d = state[3], 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
|
|
|
|
state[0] += a;
|
|
state[1] += b;
|
|
state[2] += c;
|
|
state[3] += d;
|
|
|
|
// Zeroize sensitive information.
|
|
|
|
memset (x, 0, sizeof (x));
|
|
}
|
|
|
|
// Encodes input (UINT4) into output (unsigned char). Assumes len is a
|
|
// multiple of 4.
|
|
void MD5::encode(unsigned char *output, UINT4 *input, unsigned int len)
|
|
{
|
|
unsigned int i, j;
|
|
|
|
for (i = 0, j = 0; j < len; i++, j += 4) {
|
|
output[j] = static_cast<unsigned char>(input[i] & 0xff);
|
|
output[j+1] = static_cast<unsigned char>((input[i] >> 8) & 0xff);
|
|
output[j+2] = static_cast<unsigned char>((input[i] >> 16) & 0xff);
|
|
output[j+3] = static_cast<unsigned char>((input[i] >> 24) & 0xff);
|
|
}
|
|
}
|
|
|
|
// Decodes input (unsigned char) into output (UINT4). Assumes len is a
|
|
// multiple of 4.
|
|
void MD5::decode(UINT4 *output, unsigned char *input, unsigned int len)
|
|
{
|
|
unsigned int i, j;
|
|
|
|
for (i = 0, j = 0; j < len; i++, j += 4)
|
|
output[i] =
|
|
static_cast<UINT4>(input[j]) |
|
|
(static_cast<UINT4>(input[j+1]) << 8) |
|
|
(static_cast<UINT4>(input[j+2]) << 16) |
|
|
(static_cast<UINT4>(input[j+3]) << 24);
|
|
}
|
|
|
|
// Public functions
|
|
|
|
MD5::MD5()
|
|
{
|
|
init();
|
|
}
|
|
|
|
void MD5::reset()
|
|
{
|
|
init();
|
|
}
|
|
|
|
void MD5::encodeString(char const* str)
|
|
{
|
|
unsigned int len = strlen(str);
|
|
|
|
update(QUtil::unsigned_char_pointer(str), len);
|
|
final();
|
|
}
|
|
|
|
void MD5::appendString(char const* input_string)
|
|
{
|
|
update(QUtil::unsigned_char_pointer(input_string), strlen(input_string));
|
|
}
|
|
|
|
void MD5::encodeDataIncrementally(char const* data, int len)
|
|
{
|
|
update(QUtil::unsigned_char_pointer(data), len);
|
|
}
|
|
|
|
void MD5::encodeFile(char const *filename, int up_to_size)
|
|
{
|
|
unsigned char buffer[1024];
|
|
|
|
FILE *file = QUtil::safe_fopen(filename, "rb");
|
|
size_t len;
|
|
int so_far = 0;
|
|
int to_try = 1024;
|
|
do
|
|
{
|
|
if ((up_to_size >= 0) && ((so_far + to_try) > up_to_size))
|
|
{
|
|
to_try = up_to_size - so_far;
|
|
}
|
|
len = fread(buffer, 1, to_try, file);
|
|
if (len > 0)
|
|
{
|
|
update(buffer, len);
|
|
so_far += len;
|
|
if ((up_to_size >= 0) && (so_far >= up_to_size))
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
} while (len > 0);
|
|
if (ferror(file))
|
|
{
|
|
// Assume, perhaps incorrectly, that errno was set by the
|
|
// underlying call to read....
|
|
(void) fclose(file);
|
|
QUtil::throw_system_error(
|
|
std::string("MD5: read error on ") + filename);
|
|
}
|
|
(void) fclose(file);
|
|
|
|
final();
|
|
}
|
|
|
|
void MD5::digest(Digest result)
|
|
{
|
|
final();
|
|
memcpy(result, digest_val, sizeof(digest_val));
|
|
}
|
|
|
|
void MD5::print()
|
|
{
|
|
final();
|
|
|
|
unsigned int i;
|
|
for (i = 0; i < 16; ++i)
|
|
{
|
|
printf("%02x", digest_val[i]);
|
|
}
|
|
printf("\n");
|
|
}
|
|
|
|
std::string MD5::unparse()
|
|
{
|
|
final();
|
|
return QUtil::hex_encode(
|
|
std::string(reinterpret_cast<char*>(digest_val), 16));
|
|
}
|
|
|
|
std::string
|
|
MD5::getDataChecksum(char const* buf, int len)
|
|
{
|
|
MD5 m;
|
|
m.encodeDataIncrementally(buf, len);
|
|
return m.unparse();
|
|
}
|
|
|
|
std::string
|
|
MD5::getFileChecksum(char const* filename, int up_to_size)
|
|
{
|
|
MD5 m;
|
|
m.encodeFile(filename, up_to_size);
|
|
return m.unparse();
|
|
}
|
|
|
|
bool
|
|
MD5::checkDataChecksum(char const* const checksum,
|
|
char const* buf, int len)
|
|
{
|
|
std::string actual_checksum = getDataChecksum(buf, len);
|
|
return (checksum == actual_checksum);
|
|
}
|
|
|
|
bool
|
|
MD5::checkFileChecksum(char const* const checksum,
|
|
char const* filename, int up_to_size)
|
|
{
|
|
bool result = false;
|
|
try
|
|
{
|
|
std::string actual_checksum = getFileChecksum(filename, up_to_size);
|
|
result = (checksum == actual_checksum);
|
|
}
|
|
catch (std::runtime_error const&)
|
|
{
|
|
// Ignore -- return false
|
|
}
|
|
return result;
|
|
}
|