Using SECPKG_ATTR_ISSUER_LIST_EX

The SECPKG_ATTR_ISSUER_LIST_EX structure returns the list of credentials that are acceptable to the server as an array of CryptoAPI CERT_NAME_BLOB structures.

When a protocol that does not support this functionality is used, this attribute returns an empty list.

SecPkgContext_IssuerListInfoEx IssuerListInfo;
SECURITY_STATUS scRet;

//--------------------------------------------------------------------
// Get list of trusted CAs.

Status = g_SecurityFunc.QueryContextAttributes(
     phContext,
     SECPKG_ATTR_ISSUER_LIST_EX,
     (PVOID)&IssuerListInfo);

if(FAILED(Status))
{
    printf("Error 0x%x querying issuer list info\n", Status);
    return FALSE;
}

//--------------------------------------------------------------------
// Find client certificate issued by one of these CAs.

//--------------------------------------------------------------------
// Free the issuer list memory.
g_SecurityFunc.FreeContextBuffer(IssuerListInfo.aIssuers);