ICEnroll::enumProviders method (xenroll.h)

Article
10/13/2021

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

The enumProviders method retrieves the names of the available cryptographic service providers (CSPs) specified by the ProviderType property. This method was first defined in the ICEnroll interface.

Syntax

HRESULT enumProviders(
  [in]  LONG dwIndex,
  [in]  LONG dwFlags,
  [out] BSTR *pbstrProvName
);

Parameters

[in] dwIndex

Specifies the ordinal position of the CSP whose name will be retrieved. Specify zero for the first CSP.

[in] dwFlags

Specifies flags that are passed through to the CryptEnumProviders function. This parameter is not currently used; specify zero.

[out] pbstrProvName

A pointer to a BSTR variable that receives the name of a CSP with the specified property type. When you have finished using the BSTR, free it by calling the SysFreeString function.

Return value

C++

The return value is an HRESULT. A value of S_OK indicates success. The value ERROR_NO_MORE_ITEMS is returned when there are no more CSPs with the property type indicated by the ProviderType property.

VB

The return value is a String variable that contains the name of a CSP. An exception is raised if an error is encountered or when there are no more items.

Remarks

If the ProviderType property value has not been set, the default value (usually PROV_RSA_FULL) of ProviderType as set in the registry, is used.

The enumProviders method calls the CryptEnumProviders function.

Examples

BSTR       bstrProvName = NULL;
DWORD      nProv;
int        j;
HRESULT    hr;

// array of CSP provider types (see Wincrypt.h)
DWORD      nProvType[] = { PROV_RSA_FULL,      
                           PROV_RSA_SIG,       
                           // list shortened for brevity
                           //...
                           PROV_STT_ISS };

// Loop, for each Prov Type.
for (j = 0; j < (sizeof(nProvType)/sizeof(DWORD)); j++)
{
    nProv = 0;
    
    // pEnroll is previously instantiated ICEnroll interface pointer
    hr = pEnroll->put_ProviderType( nProvType[j] );
    if ( FAILED(hr))
    {
        printf("Failed put_ProviderType - %x\n", hr);
        goto error;
    }
    // Enumerate the CSPs of this type.
    while ( S_OK == ( hr = pEnroll->enumProviders(nProv,
                                                  0,
                                                  &bstrProvName)))
    {
        printf("Provider %ws (type %d )\n", bstrProvName, 
            nProvType[j] );
        nProv++;
        if ( bstrProvName )
        {
            SysFreeString( bstrProvName );
            bstrProvName = NULL;
        }
    }

    // Print message if provider type does not have any CSPs.
    if ( 0 == nProv )
       printf("There were no CSPs of type %d\n", dwType );
}

error:
// Clean up resources, and so on.
if ( bstrProvName )
    SysFreeString( bstrProvName );

Requirements

Requirement	Value
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