Getting an exception/error when using Win32 API to create Hash string using Sha1 Algorithm

EDN Admin · Feb 21, 2012

void main (){
CString sHashedPwd = "TNVBalaji"; 
<span style="white-space

re SHA1Hash(pwd, sHashedPwd.GetBuffer());

}
// plainText: Original text to be hash 
// hashCode:<span style="white-space

re text to store hashed code, which is 40 character long string.
bool CPwdMgrX::SHA1Hash(LPCTSTR plainText, LPTSTR hashCode) 
{ 
<span style="white-space

re bool<span style="white-space

re rc<span style="white-space

re
= true;<span style="white-space

re // Default is success 
<span style="white-space

re TCHAR<span style="white-space

re rstData[256]= {0};<span style="white-space

re
// Buffer to receive hashed result 
<span style="white-space

re ALG_ID<span style="white-space

re
algorithmID<span style="white-space

re = CALG_SHA1; // Use SHA1 algorithm 
<span style="white-space

re HCRYPTPROV hProv = NULL; // Handle to a cryptographic service provider (CSP). 
<span style="white-space

re HCRYPTHASH hHash = NULL; // Handle to the hash object needed to create a hash. 
<span style="white-space

re PBYTE pbHash = NULL; // Pointer to the hash. 
<span style="white-space

re DWORD dwDataLen = 0; // Length, in bytes, of the hash. 
 
 
<span style="white-space

re //-------------------------------------------------------------------- 
<span style="white-space

re // Acquire a handle to the default RSA cryptographic service provider. 
<span style="white-space

re if (!CryptAcquireContext( 
<span style="white-space

re &hProv, // handle of the CSP 
<span style="white-space

re NULL, // key container name 
<span style="white-space

re NULL, // CSP name 
<span style="white-space

re PROV_RSA_FULL, // provider type 
<span style="white-space

re CRYPT_VERIFYCONTEXT)) // no key access is requested 
<span style="white-space

re { 
<span style="white-space

re printf(" Error in AcquireContext 0x%08x n", GetLastError()); 
<span style="white-space

re rc = false; 
<span style="white-space

re goto ErrorExit; 
<span style="white-space

re } 
 
 
<span style="white-space

re if (!CryptCreateHash( 
<span style="white-space

re hProv, // handle of the CSP 
<span style="white-space

re algorithmID, // hash algorithm to use 
<span style="white-space

re 0, // hash key 
<span style="white-space

re 0, // reserved 
<span style="white-space

re &hHash)) // address of hash object handle 
<span style="white-space

re { 
<span style="white-space

re printf("Error in CryptCreateHash 0x%08x n", GetLastError()); 
<span style="white-space

re rc = false; 
<span style="white-space

re goto ErrorExit; 
<span style="white-space

re } 
 
 
<span style="white-space

re if (!CryptHashData( 
<span style="white-space

re hHash, // handle of the hash object 
<span style="white-space

re (const BYTE *) plainText, // text to be hash 
<span style="white-space

re _tcslen(plainText)*sizeof(TCHAR), // number of bytes of data 
<span style="white-space

re 0)) // flags 
<span style="white-space

re { 
<span style="white-space

re printf("Error in CryptHashData 0x%08x n", GetLastError()); 
<span style="white-space

re rc = false; 
<span style="white-space

re goto ErrorExit; 
<span style="white-space

re } 
 
 
<span style="white-space

re if (!CryptGetHashParam( 
<span style="white-space

re hHash, // handle of the HMAC hash object 
<span style="white-space

re HP_HASHVAL, // query on the hash value 
<span style="white-space

re NULL, // pointer to the HMAC hash value 
<span style="white-space

re &dwDataLen, // length,in bytes, of the hash 
<span style="white-space

re 0)) 
<span style="white-space

re { 
<span style="white-space

re printf("Error in CryptGetHashParam 0x%08x n", GetLastError()); 
<span style="white-space

re rc = false; 
<span style="white-space

re goto ErrorExit; 
<span style="white-space

re } 
 
 
<span style="white-space

re pbHash = (BYTE*)malloc(dwDataLen); 
<span style="white-space

re if(NULL == pbHash) 
<span style="white-space

re { 
<span style="white-space

re printf("unable to allocate memoryn"); 
<span style="white-space

re goto ErrorExit; 
<span style="white-space

re } 
 
 
<span style="white-space

re if (!CryptGetHashParam( 
<span style="white-space

re hHash, // handle of the HMAC hash object 
<span style="white-space

re HP_HASHVAL, // query on the hash value 
<span style="white-space

re pbHash, // pointer to the HMAC hash value 
<span style="white-space

re &dwDataLen, // length,in bytes, of the hash 
<span style="white-space

re 0)) 
<span style="white-space

re { 
<span style="white-space

re printf("Error in CryptGetHashParam 0x%08x n", GetLastError()); 
<span style="white-space

re rc = false; 
<span style="white-space

re goto ErrorExit; 
<span style="white-space

re } 
 
 
<span style="white-space

re //CString s = (char*)pbHash; 
<span style="white-space

re TCHAR tmpBuffer[3] = {0}; 
<span style="white-space

re for (DWORD i = 0 ; i < dwDataLen ; i++) 
<span style="white-space

re { 
<span style="white-space

re tmpBuffer[0] = 0; tmpBuffer[1] = 0; tmpBuffer[2] = 0;<span style="white-space

re
// clear 
<span style="white-space

re _stprintf_s(tmpBuffer, _T("%2.2x"),pbHash); 



 
 

ErrorExit: 





free(pbHash); 
 

}

Error Message
=================
--------------------------- 
Microsoft Visual C++ Debug Library 
--------------------------- 
Debug Assertion Failed! 
 
 
Program: Crogram FilesInternet ExplorerIEXPLORE.EXE 
File: f:ddvctoolscrt_bldself_x86crtsrcdbgheap.c 
Line: 1317 
 
 
Expression: _CrtIsValidHeapPointer(pUserData) 
 
 
For information on how your program can cause an assertion 
failure, see the Visual C++ documentation on asserts. 
 
 
(Press Retry to debug the application) 
--------------------------- 
Abort Retry Ignore 
--------------------------- 

Please Help to resolve the issue.
<hr class="sig www.tnvbalaji.com

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Getting an exception/error when using Win32 API to create Hash string using Sha1 Algorithm

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