decryption code throwing a hissyfit.

[hazz]

Here is a method that throws a NullReferenceException at the line pointed to
below . szCharKey is undefined at that point.
Before FromDoubleByte() is called , szCharkey has a value of "1234"

The call stack shows FromDoubleByte(char* pszIn = 0x001bfb18, unsigned char*
pbOut = 0x0012eb10, __int32 nBufLen = 880) Line 228 C++

Any ideas where I should look? values for szStringToDecrypt and pszIn are
given at bottom. Thank you. -greg
----------------------------------------------------------------------------
------------------------------------

String* DeCryptString(String &szStringToDecrypt, String &szCharKey)
{
HCRYPTPROV hProv = NULL;
HCRYPTKEY hKey = NULL;
HCRYPTHASH hHash = NULL;
PBYTE pbBuffer = NULL;
int nCount = 0;
String* sDecryptedString;
BYTE ucCondensed[MAX_PATH];

int nBufLen = szStringToDecrypt.Length;
char* pszDoubleWideString =
(char*)(void*)Marshal::StringToHGlobalAnsi(&szStri ngToDecrypt);
FromDoubleByte( pszDoubleWideString, ucCondensed, nBufLen );
nBufLen /= 2;

String* sKey;
if(szCharKey.Length > 0) <----------------//NullReferenceExeption thrown
here
..........
}
void FromDoubleByte(char* pszIn, PBYTE pbOut, int nBufLen)
-----------------
{
int i;
int j;
int nOneChar;
int nByteValue;

for( i=0, j=0; i< (long)nBufLen; )
{
// Read first of two bytes
nOneChar = pszIn[i++];
if( nOneChar < 58 )
{
nByteValue = (( nOneChar - '0' ) * 16);
}
else
{
nByteValue = (( nOneChar - ( 'A' - 10 ) ) * 16);
}

// Read second of two bytes
nOneChar = pszIn[i++];
if( nOneChar < 58 )
{
nByteValue += ( nOneChar - '0' );
}
else
{
nByteValue += ( nOneChar - ( 'A' - 10 ) );
}

//Put in buffer
pbOut[j++] = (unsigned char)nByteValue;
}
}


szStringToDecrypt =
"5E45D91532071793F87E543E6DF59A6A792F9790918F6D2F1 D80D3D9D34B9DA92DB536343C7
D71A371F68485271A9B6AD57CDD654770C015852A78E573551 FDFD0B40529DB28CD6A55F3098
02488212CEB9A15C5C1CC464826D05762D83B0989AA8AD26F5 748A93FC853820319423ABE788
8571058CCEC9D46DC22F8F42BA7550ADE3E857D5F86FBD3E34 15B885E9489058D635FBF2DD49
96EA62302F6A84AC997C42936CA3A2BFB631D10D7542E6B267 D302A1F93D40F4926CB929FE81
FD66AAB96D7F0F1B51ACCC5C74C0C4B0AAE240C3CD0A2AEBA4 5F44D02771D584353969E9CBD3
F00E99F5CF7797B06F7D4350EABA81A4CEDCD288FE38445817 237936621E367791EE49CC09DB
C6227600CF361923B2BDF81E96496B103A17B6884C985E4855 9B4DA50B266B4438A5E2A8762E
70A0CFED667F0677E717CF14014C9D4429F694D2A0654B6E13 A612B7B40EF3E122B01992640C
3C6484B493A293BA4FB9AEFCA94F3BD2365FAAF917358F3AA6 7FE9FD15B978FDF772E3EC3A77
246A3D70996449DCBC145FE83FBA54F653EB5E60D624D48508 505AAB612AEC0E115F5F47D7A5
CDE68F22662F1D693A133337B2C512957D2C4F0DA84D9"

pszIn = 0x001bfb70
"8D1E82F58E8953AD3ED791461570E2D57E8DB057CEB5BC4E1 74B466354E04FE3D091A03F1E4
7612BCC7CB4409AF6BB44B06277F4D065ABD70B204B23CE940 10D1DEB5B443664BCDF3B7BE04
59C45DCD80B03B232040A5267225882E510CB45966F1EDD9B0 323EAC7BC8FD36993B34899210
2303570420323A967DB1517D8F99H" char*

[hazz]

if szStringToDecrypt is shorter than the offending input string to encrypt,
as when "test" is the encrypted string, no problem.

"hazz" <ha**@sonic.net> wrote in message
news:eT**************@tk2msftngp13.phx.gbl...

Here is a method that throws a NullReferenceException at the line pointed to below . szCharKey is undefined at that point.
Before FromDoubleByte() is called , szCharkey has a value of "1234"

The call stack shows FromDoubleByte(char* pszIn = 0x001bfb18, unsigned char* pbOut = 0x0012eb10, __int32 nBufLen = 880) Line 228 C++

Any ideas where I should look? values for szStringToDecrypt and pszIn are
given at bottom. Thank you. -greg
-------------------------------------------------------------------------- -- ------------------------------------

String* DeCryptString(String &szStringToDecrypt, String &szCharKey)
{
HCRYPTPROV hProv = NULL;
HCRYPTKEY hKey = NULL;
HCRYPTHASH hHash = NULL;
PBYTE pbBuffer = NULL;
int nCount = 0;
String* sDecryptedString;
BYTE ucCondensed[MAX_PATH];

int nBufLen = szStringToDecrypt.Length;
char* pszDoubleWideString =
(char*)(void*)Marshal::StringToHGlobalAnsi(&szStri ngToDecrypt);
FromDoubleByte( pszDoubleWideString, ucCondensed, nBufLen );
nBufLen /= 2;

String* sKey;
if(szCharKey.Length > 0) <----------------//NullReferenceExeption thrown here
.........
}
void FromDoubleByte(char* pszIn, PBYTE pbOut, int nBufLen)
-----------------
{
int i;
int j;
int nOneChar;
int nByteValue;

for( i=0, j=0; i< (long)nBufLen; )
{
// Read first of two bytes
nOneChar = pszIn[i++];
if( nOneChar < 58 )
{
nByteValue = (( nOneChar - '0' ) * 16);
}
else
{
nByteValue = (( nOneChar - ( 'A' - 10 ) ) * 16);
}

// Read second of two bytes
nOneChar = pszIn[i++];
if( nOneChar < 58 )
{
nByteValue += ( nOneChar - '0' );
}
else
{
nByteValue += ( nOneChar - ( 'A' - 10 ) );
}

//Put in buffer
pbOut[j++] = (unsigned char)nByteValue;
}
}


szStringToDecrypt =
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

pszIn = 0x001bfb70
"8D1E82F58E8953AD3ED791461570E2D57E8DB057CEB5BC4E1 74B466354E04FE3D091A03F1E4 7612BCC7CB4409AF6BB44B06277F4D065ABD70B204B23CE940 10D1DEB5B443664BCDF3B7BE04 59C45DCD80B03B232040A5267225882E510CB45966F1EDD9B0 323EAC7BC8FD36993B34899210 2303570420323A967DB1517D8F99H" char*