Error while trying to create a Custom Windows Authentication Service

Question

I'm currently working on creating a Custom Windows Authentication System in Windows 11. I am using this GitHub project for starting reference. I've developed a DLL to implement a custom login layer on the Windows Login Tile. However, after entering a valid username and password in the tile fields, the system doesn't proceed to the next step—it loads for a while and then says "Incorrect username or password." Do you have any suggestions on how this issue can be resolved? Or can you help me find any other better way to create a Custom Windows Authentication flow (i.e. using custom fields, custom biometric devices, etc.)?

Code snippet

        public List<_CREDENTIAL_PROVIDER_FIELD_DESCRIPTOR> CredentialProviderFieldDescriptorList = new List<_CREDENTIAL_PROVIDER_FIELD_DESCRIPTOR> {

            new _CREDENTIAL_PROVIDER_FIELD_DESCRIPTOR

            {

                cpft = _CREDENTIAL_PROVIDER_FIELD_TYPE.CPFT_SMALL_TEXT,

                dwFieldID = 0,

                pszLabel = "Welcome to Custom Windows Login",

            },

            new _CREDENTIAL_PROVIDER_FIELD_DESCRIPTOR

            {

                cpft = _CREDENTIAL_PROVIDER_FIELD_TYPE.CPFT_SUBMIT_BUTTON,

                dwFieldID = 1,

                pszLabel = "Login",

            },

            new _CREDENTIAL_PROVIDER_FIELD_DESCRIPTOR

            {

                cpft = _CREDENTIAL_PROVIDER_FIELD_TYPE.CPFT_EDIT_TEXT, // Username field

                dwFieldID = FIELD_ID_USERNAME,

                pszLabel = "Enter Username",

            },

            new _CREDENTIAL_PROVIDER_FIELD_DESCRIPTOR

            {

                cpft = _CREDENTIAL_PROVIDER_FIELD_TYPE.CPFT_PASSWORD_TEXT, // Password field

                dwFieldID = FIELD_ID_PASSWORD,

                pszLabel = "Enter Password",

            }

    out _CREDENTIAL_PROVIDER_CREDENTIAL_SERIALIZATION pcpcs, out string ppszOptionalStatusText,

    out _CREDENTIAL_PROVIDER_STATUS_ICON pcpsiOptionalStatusIcon)

        {

            Log.LogMethodCall();

            // Hardcoded valid credentials

            string validUsername = "username";

            string validPassword = "password";

            try

            {

                // Validate the username and password against hardcoded values

                if (username == validUsername && password == validPassword)

                {

                    // If valid, proceed with the authentication process

                    pcpgsr = _CREDENTIAL_PROVIDER_GET_SERIALIZATION_RESPONSE.CPGSR_RETURN_CREDENTIAL_FINISHED;

                    pcpcs = new _CREDENTIAL_PROVIDER_CREDENTIAL_SERIALIZATION();

                    var inCredSize = 0;

                    var inCredBuffer = Marshal.AllocCoTaskMem(0);

                    if (!PInvoke.CredPackAuthenticationBuffer(0, username, password, inCredBuffer, ref inCredSize))

                    {

                        Marshal.FreeCoTaskMem(inCredBuffer);

                        inCredBuffer = Marshal.AllocCoTaskMem(inCredSize);

                        if (PInvoke.CredPackAuthenticationBuffer(0, username, password, inCredBuffer, ref inCredSize))

                        {

                            ppszOptionalStatusText = "Login successful";

                            pcpsiOptionalStatusIcon = _CREDENTIAL_PROVIDER_STATUS_ICON.CPSI_SUCCESS;

                            pcpcs.clsidCredentialProvider = Guid.Parse(Constants.CredentialProviderUID);

                            pcpcs.rgbSerialization = inCredBuffer;

                            pcpcs.cbSerialization = (uint)inCredSize;

                            RetrieveNegotiateAuthPackage(out var authPackage);

                            pcpcs.ulAuthenticationPackage = authPackage;

                            return HResultValues.S_OK;

                        }

                    }

                    Marshal.FreeCoTaskMem(inCredBuffer);

                    ppszOptionalStatusText = "Failed to pack credentials";

                    pcpsiOptionalStatusIcon = _CREDENTIAL_PROVIDER_STATUS_ICON.CPSI_ERROR;

                    return HResultValues.E_FAIL;

                }

                else

                {

                    // If invalid, return an error message

                    ppszOptionalStatusText = "Invalid username or password";

                    pcpsiOptionalStatusIcon = _CREDENTIAL_PROVIDER_STATUS_ICON.CPSI_ERROR;

                    // Indicate that the credential serialization failed

                    pcpgsr = _CREDENTIAL_PROVIDER_GET_SERIALIZATION_RESPONSE.CPGSR_NO_CREDENTIAL_NOT_FINISHED;

                    pcpcs = new _CREDENTIAL_PROVIDER_CREDENTIAL_SERIALIZATION();

                    return HResultValues.E_FAIL;

                }

            }

            catch (Exception ex)

            {

                // Handle any unexpected exceptions

                ppszOptionalStatusText = $"An error occurred: {ex.Message}";

                pcpsiOptionalStatusIcon = _CREDENTIAL_PROVIDER_STATUS_ICON.CPSI_ERROR;

                pcpgsr = _CREDENTIAL_PROVIDER_GET_SERIALIZATION_RESPONSE.CPGSR_NO_CREDENTIAL_NOT_FINISHED;

                pcpcs = new _CREDENTIAL_PROVIDER_CREDENTIAL_SERIALIZATION();

                return HResultValues.E_FAIL;

            }

    } 

Error message

This is a generated error message that I found on the Windows Event Viewer:

An account failed to log on.

Subject:

	Security ID:		SYSTEM

	Account Name:		DESKTOP-476EOJ1$

	Account Domain:		WORKGROUP

	Logon ID:		0x3E7

Logon Type:			2

Account For Which Logon Failed:

	Security ID:		NULL SID

	Account Name:		-

	Account Domain:		-

Failure Information:

	Failure Reason:		Unknown user name or bad password.

	Status:			0xC000006D

	Sub Status:		0xC000006A

Process Information:

	Caller Process ID:	0x860

	Caller Process Name:	C:\Windows\System32\svchost.exe

Network Information:

	Workstation Name:	-

	Source Network Address:	127.0.0.1

	Source Port:		0

Detailed Authentication Information:

	Logon Process:		User32 

	Authentication Package:	Negotiate

	Transited Services:	-

	Package Name (NTLM only):	-

	Key Length:		0

This event is generated when a logon request fails. It is generated on the computer where access was attempted.

Answer 1

Hi, I am Dave, I will help you with this.

I apologize, Community is just a consumer forum, due to the scope of your question can you please post this question to our sister forum on Microsoft Q&A (The Developers Forum) in the C# section (linked below)

Over there you will have access to a host of Developers and C# Programming experts and will get a knowledgeable and quick answer to this question.

https://learn.microsoft.com/en-us/answers/tags/...