ICEnroll4::GetKeyLenEx method (xenroll.h)

[This method is no longer available for use as of Windows Server 2008 and Windows Vista.]

The GetKeyLenEx method retrieves size information for the signature and exchange keys. This method was first defined in the ICEnroll4 interface.

The values retrieved by this method are dependent upon the current cryptographic service provider (CSP).

Syntax

HRESULT GetKeyLenEx(
  LONG lSizeSpec,
  LONG lKeySpec,
  LONG *pdwKeySize
);

Parameters

lSizeSpec

A value that indicates the type of size information to be retrieved. This parameter can be one of the following values.

Value Meaning
XEKL_KEYSIZE_MIN
The minimum key size.
XEKL_KEYSIZE_MAX
The maximum key size.
XEKL_KEYSIZE_INC
The size of the key increment. For more information, see Remarks.

lKeySpec

Specifies the key for which size information is returned. This parameter can be one of the following values.

Value Meaning
XEKL_KEYSPEC_KEYX
Exchange key
XEKL_KEYSPEC_SIG
Signature key

pdwKeySize

A pointer to a variable that receives the key size, in bits.

Return value

C++

If the method succeeds, the method returns S_OK.

If the method fails, it returns an HRESULT value that indicates the error. For a list of common error codes, see Common HRESULT Values.

VB

A value that represents the key size, in bits.

Remarks

If the CSP does not support this method, an error is returned.

For more information about the XEKL_KEYSIZE_INC value, see PP_SIG_KEYSIZE_INC usage in the CryptGetProvParam reference page.

Examples

DWORD dwExchMin, dwExchMax, dwSignDef, dwSignInc;

// Determine the minimum and maximum key length values.
// hr is HRESULT variable.
hr = pEnroll4->GetKeyLenEx( XEKL_KEYSIZE_MIN,
                            XEKL_KEYSPEC_KEYX,
                            &dwExchMin );
if ( FAILED( hr ) )    
    printf("Failed GetKeyLenEx for Exchange Minimum [%x]\n", hr);
else
    printf("Exchange key Min: %d\n", dwExchMin);

hr = pEnroll4->GetKeyLenEx( XEKL_KEYSIZE_MAX,
                            XEKL_KEYSPEC_KEYX,
                            &dwExchMax );
if ( FAILED( hr ) )
    printf("Failed GetKeyLenEx for Exchange Maximum [%x]\n", hr);
else
    printf("Exchange key Max: %d\n", dwExchMax );

hr = pEnroll4->GetKeyLenEx( XEKL_KEYSIZE_DEFAULT,
                            XEKL_KEYSPEC_SIG,
                            &dwSignDef );
if ( FAILED( hr ) )
    printf("Failed GetKeyLenEx for Signature Default "
   "Key size [%x]\n", hr);
else
    printf("Signature key default size: %d\n", dwSignDef );

hr = pEnroll4->GetKeyLenEx( XEKL_KEYSIZE_INC,
                            XEKL_KEYSPEC_SIG,
                            &dwSignInc );
if ( FAILED( hr ) )    
    printf("Failed GetKeyLenEx for Signature "
   "Key Size Increment [%x]\n", hr);
else
    printf("Signature key increment size: %d\n", dwSignInc );

Requirements

   
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Target Platform Windows
Header xenroll.h
Library Uuid.lib
DLL Xenroll.dll