CryptEnumProviderTypes

This function is used to enumerate the types of providers supported on the machine.

At a Glance

Syntax

BOOL WINAPI CryptEnumProviderTypes( DWORD dwIndex,
DWORD *pdwReserved, DWORD dwFlags, DWORD *pdwProvType,
LPTSTR pszTypeName, DWORD *pcbTypeName );

Parameters

dwIndex

[in] Specifies the index of the next provider type to be enumerated.

pdwReserved

[in] Reserved for future use ; set to NULL.

dwFlags

[in] Specifies a bitmask of flags. This parameter is reserved for future use and should always be zero.

pdwProvType

[in] Pointer to the DWORD value that designates the enumerated provider type.

pszTypeName

[out] Pointer to a buffer that receives the data from the enumerated provider type. A null-terminated string. There are provider types which may not have friendly names and in this case no name will be returned and the returned value pointed to by pcbTypeName will be 0.

This parameter can be NULL if you want to get the size of the name for memory allocation purposes.

pcbTypeName

[in/out] Pointer to a variable that specifies the size, in bytes, of the buffer pointed to by the pszTypeName parameter. When the function returns, the variable pointed to by the pcbTypeName parameter contains the number of bytes stored in the buffer. There are provider types which may not have friendly names and in this case no name will be returned and the returned value pointed to by pcbTypeName will be 0.

Note   When processing the data returned in the buffer, applications need to use the actual size of the data returned. The actual size may be slightly smaller than the size of the buffer specified on input. (On input, buffer sizes are usually specified large enough to ensure that the largest possible output data will fit in the buffer.) On output, the variable pointed to by this parameter is updated to reflect the actual size of the data copied to the buffer.

Return Values

TRUE indicates success. FALSE indicates failure. To get extended error information, call GetLastError. Common values for GetLastError are described in the following table. The error values prefaced by "NTE" are generated by the particular CSP you are using.

Remarks

CryptEnumProviderTypes is used to enumerate the provider types on a machine. Once this is done, the providers for a specific type may be enumerated by using CryptEnumProviders.

Windows CE does not support the ANSI version of this function.

Example

long i;
DWORD dwErr;

// Loop through enumerating provider types.
for (i=0;;i++)
{
if (!CryptEnumProviderTypes(i, NULL, 0, &dwType, NULL, NULL))
 {if (ERROR_NO_MORE_ITEMS != (dwErr = GetLastError()))
 {printf("ERROR - CryptEnumProviderTypes : %X\n", dwErr);
 }
 break;
 }
printf ("Provider Type %d\n", dwType);
}

See Also

CryptEnumProviders