You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
422 lines
9.6 KiB
422 lines
9.6 KiB
//+--------------------------------------------------------------------------
|
|
//
|
|
// Copyright (c) 1997-1999 Microsoft Corporation
|
|
//
|
|
// File:
|
|
//
|
|
// Contents:
|
|
//
|
|
// History:
|
|
//
|
|
//---------------------------------------------------------------------------
|
|
#include <windows.h>
|
|
#include <assert.h>
|
|
#include <math.h>
|
|
|
|
|
|
class CDataCoding {
|
|
private:
|
|
DWORD m_dwBaseDigits;
|
|
|
|
DWORD m_dwEncodedLength;
|
|
DWORD m_dwInputDataBits;
|
|
DWORD m_dwInputDataBytes;
|
|
|
|
DWORD m_dwDecodedLength;
|
|
DWORD m_dwInputEncDataBytes;
|
|
DWORD m_dwDecodedBits;
|
|
|
|
TCHAR * m_tpBaseDigits;
|
|
|
|
public:
|
|
CDataCoding(TCHAR * tpBaseDigits = NULL);
|
|
|
|
void SetInputDataBitLen(DWORD dwBits);
|
|
void SetInputEncDataLen(DWORD dwChars);
|
|
DWORD SetBaseDigits(TCHAR * tpBaseDigits);
|
|
DWORD EncodeData(LPBYTE pbSource, //[IN] Stream of Bytes to be encoded
|
|
TCHAR **pbEncodedData); //[OUT] Pointer to a string containing the encoded data
|
|
DWORD DecodeData(TCHAR * pbEncodedData,
|
|
LPBYTE * pbDecodedData);
|
|
|
|
~CDataCoding();
|
|
};
|
|
|
|
|
|
class CBase24Coding : public CDataCoding {
|
|
public:
|
|
CBase24Coding(void) : CDataCoding(L"BCDFGHJKMPQRTVWXY2346789")
|
|
{
|
|
return;
|
|
}
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
static CBase24Coding b24Global;
|
|
|
|
|
|
// **************************************************************
|
|
DWORD B24EncodeMSID(LPBYTE pbSource, TCHAR **pbEncodedData)
|
|
{
|
|
b24Global.SetInputDataBitLen(160);
|
|
|
|
return b24Global.EncodeData(pbSource, pbEncodedData);
|
|
}
|
|
|
|
|
|
// ***************************************************************
|
|
DWORD B24DecodeMSID(TCHAR * pbEncodedData, LPBYTE * pbDecodedData)
|
|
{
|
|
b24Global.SetInputEncDataLen(35);
|
|
|
|
return b24Global.DecodeData(pbEncodedData, pbDecodedData);
|
|
}
|
|
|
|
|
|
|
|
|
|
// ***********************************************************
|
|
DWORD B24EncodeCNumber(LPBYTE pbSource, TCHAR **pbEncodedData)
|
|
{
|
|
b24Global.SetInputDataBitLen(32);
|
|
|
|
return b24Global.EncodeData(pbSource, pbEncodedData);
|
|
}
|
|
|
|
|
|
// ******************************************************************
|
|
DWORD B24DecodeCNumber(TCHAR * pbEncodedData, LPBYTE * pbDecodedData)
|
|
{
|
|
b24Global.SetInputEncDataLen(7);
|
|
|
|
return b24Global.DecodeData(pbEncodedData, pbDecodedData);
|
|
}
|
|
|
|
|
|
|
|
|
|
// *******************************************************
|
|
DWORD B24EncodeSPK(LPBYTE pbSource, TCHAR **pbEncodedData)
|
|
{
|
|
b24Global.SetInputDataBitLen(114);
|
|
|
|
return b24Global.EncodeData(pbSource, pbEncodedData);
|
|
}
|
|
|
|
|
|
// ******************************************************************
|
|
DWORD B24DecodeSPK(TCHAR * pbEncodedData, LPBYTE * pbDecodedData)
|
|
{
|
|
b24Global.SetInputEncDataLen(25);
|
|
|
|
return b24Global.DecodeData(pbEncodedData, pbDecodedData);
|
|
}
|
|
|
|
|
|
|
|
// *****************************************
|
|
CDataCoding::CDataCoding(TCHAR * tpBaseDigits)
|
|
{
|
|
m_tpBaseDigits = NULL;
|
|
m_dwBaseDigits = 0;
|
|
m_dwEncodedLength = 0;
|
|
m_dwInputDataBits = 0;
|
|
m_dwInputDataBytes = 0;
|
|
SetBaseDigits(tpBaseDigits);
|
|
}
|
|
|
|
|
|
|
|
// ********************************************
|
|
void CDataCoding::SetInputDataBitLen(DWORD dwBits)
|
|
{
|
|
assert(dwBits > 0);
|
|
assert(log(m_dwBaseDigits) > 0);
|
|
|
|
// Determine How many Characters would be required to encode the data
|
|
// What we have is a dwDataLength of Binary Data stream.
|
|
// So, we can represent 2^(dwDataLength*8) amount of information using these bits
|
|
// Assuming that our set of digits (which form the base for encoding) is X,
|
|
// the above number should then equal X^(NumberofEncoded Digits)
|
|
// So,
|
|
double dLength = ((double) dwBits*log10(2)) /
|
|
((double) log10(m_dwBaseDigits));
|
|
|
|
// Now round - up
|
|
m_dwEncodedLength = (DWORD) dLength;
|
|
|
|
if ((double) m_dwEncodedLength < dLength)
|
|
{
|
|
// There was a decimal part
|
|
m_dwEncodedLength++;
|
|
}
|
|
m_dwInputDataBits = dwBits;
|
|
m_dwInputDataBytes = (dwBits / 8) + (dwBits % 8 ? 1 : 0);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
// ***********************************************
|
|
void CDataCoding::SetInputEncDataLen(DWORD dwBytes)
|
|
{
|
|
assert(dwBytes > 0);
|
|
assert(log(m_dwBaseDigits) > 0);
|
|
|
|
m_dwInputEncDataBytes = dwBytes;
|
|
// Determine How many bits would be required to decode this data
|
|
// So,
|
|
|
|
double dLength = ((double) dwBytes*log10(m_dwBaseDigits))/
|
|
((double) log10(2));
|
|
|
|
// Now round - up
|
|
m_dwDecodedBits = (DWORD) dLength;
|
|
|
|
if ((double) m_dwDecodedBits < dLength)
|
|
{
|
|
// There was a decimal part
|
|
m_dwDecodedBits++;
|
|
}
|
|
|
|
m_dwDecodedLength = (m_dwDecodedBits / 8) + (m_dwDecodedBits % 8 ? 1 : 0);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
|
|
|
|
// **************************************************
|
|
DWORD CDataCoding::SetBaseDigits(TCHAR * tpBaseDigits)
|
|
{
|
|
DWORD dwReturn = ERROR_SUCCESS;
|
|
|
|
if (tpBaseDigits != NULL)
|
|
{
|
|
DWORD dwLen = wcslen(tpBaseDigits);
|
|
assert(dwLen > 0);
|
|
m_tpBaseDigits = (TCHAR *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, (dwLen+1)*sizeof(TCHAR));
|
|
if (m_tpBaseDigits == NULL)
|
|
{
|
|
dwReturn = ERROR_NOT_ENOUGH_MEMORY;
|
|
}
|
|
else
|
|
{
|
|
memcpy(m_tpBaseDigits, tpBaseDigits, (dwLen+1)*sizeof(TCHAR));
|
|
m_dwBaseDigits = dwLen;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (m_tpBaseDigits != NULL)
|
|
{
|
|
HeapFree(GetProcessHeap(), 0, m_tpBaseDigits);
|
|
m_tpBaseDigits = NULL;
|
|
m_dwBaseDigits = 0;
|
|
}
|
|
assert(m_tpBaseDigits == NULL && m_dwBaseDigits == 0);
|
|
}
|
|
|
|
return dwReturn;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// ************************************************
|
|
DWORD CDataCoding::EncodeData(LPBYTE pbSource, //[IN] Stream of Bytes to be encoded
|
|
TCHAR **pbEncodedData) //[OUT] Pointer to a string containing the encoded data
|
|
// I allocate the Buffer, you should free it
|
|
{
|
|
assert(m_dwInputDataBits > 0);
|
|
assert(m_dwInputDataBytes > 0);
|
|
assert(m_dwEncodedLength > 0);
|
|
assert(m_tpBaseDigits != NULL);
|
|
|
|
DWORD dwReturn = ERROR_SUCCESS;
|
|
int nStartIndex = m_dwEncodedLength;
|
|
*pbEncodedData = NULL;
|
|
BYTE * pbDataToEncode = NULL;
|
|
TCHAR * pbEncodeBuffer = NULL;
|
|
|
|
if (NULL == pbEncodedData)
|
|
{
|
|
dwReturn = ERROR_INVALID_PARAMETER;
|
|
goto done;
|
|
}
|
|
|
|
*pbEncodedData = NULL;
|
|
|
|
pbEncodeBuffer = (TCHAR *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY,
|
|
(m_dwEncodedLength+1)*sizeof(TCHAR));
|
|
if (pbEncodeBuffer == NULL)
|
|
{
|
|
dwReturn = ERROR_NOT_ENOUGH_MEMORY;
|
|
goto done;
|
|
}
|
|
|
|
// Now need to make a copy of the incoming data, so we can run the algorithm below
|
|
pbDataToEncode = (BYTE *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, m_dwInputDataBytes);
|
|
if (pbDataToEncode == NULL)
|
|
{
|
|
dwReturn = ERROR_NOT_ENOUGH_MEMORY;
|
|
goto done;
|
|
}
|
|
memcpy(pbDataToEncode, pbSource, m_dwInputDataBytes);
|
|
|
|
|
|
// Let us get rid of the simple stuff
|
|
pbEncodeBuffer[ nStartIndex--] = 0;
|
|
|
|
for (; nStartIndex >= 0; --nStartIndex)
|
|
{
|
|
unsigned int i = 0;
|
|
|
|
for (int nIndex = m_dwInputDataBytes-1; 0 <= nIndex; --nIndex)
|
|
{
|
|
i = (i * 256) + pbDataToEncode[nIndex];
|
|
pbDataToEncode[ nIndex] = (BYTE)(i / m_dwBaseDigits);
|
|
i %= m_dwBaseDigits;
|
|
}
|
|
|
|
// i now contains the remainder, which is the current digit
|
|
pbEncodeBuffer[ nStartIndex] = m_tpBaseDigits[ i];
|
|
}
|
|
|
|
assert(dwReturn == ERROR_SUCCESS);
|
|
*pbEncodedData = pbEncodeBuffer;
|
|
|
|
done:
|
|
if (pbDataToEncode != NULL)
|
|
{
|
|
HeapFree(GetProcessHeap(), 0, pbDataToEncode);
|
|
}
|
|
|
|
if (dwReturn != ERROR_SUCCESS)
|
|
{
|
|
// There was an error, so free the memory that you allocated
|
|
if (pbEncodeBuffer != NULL)
|
|
{
|
|
HeapFree(GetProcessHeap(), 0, pbEncodeBuffer);
|
|
}
|
|
}
|
|
return dwReturn;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
// *************************************************
|
|
DWORD CDataCoding::DecodeData(TCHAR * pbEncodedData,
|
|
LPBYTE * pbDecodedData)
|
|
// Again, I allocate the Buffer, you release it
|
|
{
|
|
assert(m_dwDecodedBits > 0);
|
|
assert(m_dwDecodedLength > 0);
|
|
assert(m_tpBaseDigits != NULL);
|
|
assert((DWORD) lstrlen(pbEncodedData) == m_dwInputEncDataBytes);
|
|
|
|
DWORD dwReturn = ERROR_SUCCESS;
|
|
TCHAR * tpTemp;
|
|
DWORD dwDigit;
|
|
unsigned int i;
|
|
unsigned int nDecodedBytes, nDecodedBytesMax = 0;
|
|
BYTE * pbDecodeBuffer = NULL;
|
|
|
|
if (NULL == pbDecodedData)
|
|
{
|
|
dwReturn = ERROR_INVALID_PARAMETER;
|
|
goto done;
|
|
}
|
|
|
|
*pbDecodedData = NULL;
|
|
|
|
pbDecodeBuffer = (BYTE *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, m_dwDecodedLength);
|
|
if ( pbDecodeBuffer == NULL)
|
|
{
|
|
dwReturn = ERROR_NOT_ENOUGH_MEMORY;
|
|
goto done;
|
|
}
|
|
|
|
memset(pbDecodeBuffer, 0, m_dwDecodedLength);
|
|
|
|
while (*pbEncodedData)
|
|
{
|
|
// First Find the position of this character in the Base Encoding Character Set
|
|
tpTemp = wcschr(m_tpBaseDigits, *pbEncodedData);
|
|
if (tpTemp == NULL)
|
|
{
|
|
// Found a character which is not in base character set
|
|
// ERROR ERROR
|
|
dwReturn = ERROR_INVALID_DATA;
|
|
goto done;
|
|
}
|
|
dwDigit = (DWORD)(tpTemp - m_tpBaseDigits);
|
|
|
|
nDecodedBytes = 0;
|
|
i = (unsigned int) dwDigit;
|
|
|
|
while (nDecodedBytes <= nDecodedBytesMax)
|
|
{
|
|
i += m_dwBaseDigits * pbDecodeBuffer[ nDecodedBytes];
|
|
pbDecodeBuffer[ nDecodedBytes] = (unsigned char)i;
|
|
i /= 256;
|
|
++nDecodedBytes;
|
|
}
|
|
|
|
if (i != 0)
|
|
{
|
|
assert(nDecodedBytes < m_dwDecodedLength);
|
|
|
|
pbDecodeBuffer[ nDecodedBytes] = (unsigned char)i;
|
|
nDecodedBytesMax = nDecodedBytes;
|
|
}
|
|
|
|
pbEncodedData++;
|
|
}
|
|
|
|
assert(dwReturn == ERROR_SUCCESS);
|
|
*pbDecodedData = pbDecodeBuffer;
|
|
|
|
done:
|
|
if (dwReturn != ERROR_SUCCESS)
|
|
{
|
|
// There was an error, so free the memory that you allocated
|
|
if (pbDecodeBuffer != NULL)
|
|
{
|
|
HeapFree(GetProcessHeap(), 0, pbDecodeBuffer);
|
|
}
|
|
}
|
|
|
|
return dwReturn;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// **********************
|
|
CDataCoding::~CDataCoding()
|
|
{
|
|
if (m_tpBaseDigits != NULL)
|
|
{
|
|
HeapFree(GetProcessHeap(), 0, m_tpBaseDigits);
|
|
m_tpBaseDigits = NULL;
|
|
m_dwBaseDigits = 0;
|
|
}
|
|
}
|
|
|