Custom authentication logic

Oct 13, 2025 by wbrum.org 130 views

Introduction

Oracle APEX (Application Express) is a low-code development platform that enables developers to create web-based applications quickly and efficiently. One of the key features of APEX is its ability to integrate with various authentication schemes, including custom authentication schemes. In this article, we will explore how to implement a custom authentication scheme in Oracle APEX using LDAP (Lightweight Directory Access Protocol).

What is LDAP?

LDAP is a protocol used for accessing and managing directory information. It is commonly used for authentication and authorization purposes. LDAP directories store information about users, groups, and other entities, and can be used to authenticate users against a central repository.

Why Use Custom Authentication in APEX?

Oracle APEX provides a built-in authentication scheme that supports various authentication methods, including LDAP. However, in some cases, you may need to implement a custom authentication scheme to meet specific requirements. This could be due to various reasons such as:

Custom authentication logic: You may need to implement custom authentication logic that is not supported by the built-in authentication scheme.
Integration with third-party systems: You may need to integrate your APEX application with third-party systems that use custom authentication protocols.
Security requirements: You may need to implement custom authentication schemes to meet specific security requirements, such as multi-factor authentication.

Implementing Custom Authentication in APEX

To implement custom authentication in APEX, you need to create a custom authentication scheme using the APEX API. Here are the steps to follow:

Step 1: Create a Custom Authentication Scheme

To create a custom authentication scheme, you need to create a new package in your APEX application. This package will contain the custom authentication logic.

CREATE OR REPLACE PACKAGE apex_authenticate_ldap AS
  FUNCTION authenticate(p_username IN VARCHAR2, p_password IN VARCHAR2) RETURN BOOLEAN;
END;
/

Step 2: Implement the Custom Authentication Logic

In this step, you need to implement the custom authentication logic in the authenticate function. This function will take the username and password as input and return a boolean value indicating whether the authentication was successful or not.

CREATE OR REPLACE PACKAGE BODY apex_authenticate_ldap AS
  FUNCTION authenticate(p_username IN VARCHAR2, p_password IN VARCHAR2) RETURN BOOLEAN
  IS
    l_bind_result NUMBER;
    l_user_dn VARCHAR2(255);
  BEGIN
    -- Get the user DN from the LDAP directory
    l_user_dn := get_user_dn(p_username);
-- Bind to the LDAP directory using the user DN and password
l_bind_result := bind_to_ldap(l_user_dn, p_password);

-- Return true if the bind was successful, false otherwise
RETURN l_bind_result = 0;

END;
END;
/

Step 3: Create a Trigger to Call the Custom Authentication Function

To call the custom authentication function, you need to create a trigger that will be executed when the user attempts to log in. This trigger will call the authenticate function and return the result to the APEX authentication engine.

CREATE OR REPLACE TRIGGER apex_authenticate_ldap_trigger
  BEFORE LOGON ON DATABASE
  FOR EACH ROW
  BEGIN
    IF apex_authenticate_ldap.authenticate(:APP_USER, :APP_PASSWORD) THEN
      :APP_AUTHENTICATED := TRUE;
    ELSE
      :APP_AUTHENTICATED := FALSE;
    END IF;
  END;
/

Step 4: Configure the Custom Authentication Scheme in APEX

To configure the custom authentication scheme in APEX, you need to go to the APEX administration page and select the custom authentication scheme from the list of available authentication schemes.

Troubleshooting Common Issues

When implementing custom authentication in APEX, you may encounter various issues. Here are some common issues and their solutions:

ORA-06550: apex_authenticate_ldap must be ...

This error occurs when the apex_authenticate_ldap package is not compiled correctly. Make sure that the package is compiled correctly and that the authenticate function is implemented correctly.
ORA-06553: PLS-221: 'APEX_AUTHENTICATE_LDAP' is not a procedure or is undefined

This error occurs when the apex_authenticate_ldap package is not created correctly. Make sure that the package is created correctly and that the authenticate function is implemented correctly.

Conclusion

Implementing custom authentication in Oracle APEX using LDAP can be a complex task, but with the right guidance, it can be achieved successfully. In this article, we have explored the steps to implement custom authentication in APEX using LDAP, including creating a custom authentication scheme, implementing the custom authentication logic, creating a trigger to call the custom authentication function, and configuring the custom authentication scheme in APEX. We have also discussed troubleshooting common issues that may occur when implementing custom authentication in APEX.

References

Oracle APEX Documentation: https://docs.oracle.com/en/database/oracle/application-express/20.2/aeui/index.html
LDAP Protocol: https://www.ietf.org/rfc/rfc4511.txt

Example Use Cases

Multi-factor authentication: You can use custom authentication in APEX to implement multi-factor authentication, where users need to provide additional authentication factors such as a one-time password or a biometric scan.
Single sign-on: You can use custom authentication in APEX to implement single sign-on, where users can access multiple applications using a single set of credentials.
Custom authentication logic: You can use custom authentication in APEX to implement custom authentication logic that is not supported by the built-in authentication scheme.
Orace APEX Custom Authentication with LDAP: Q&A =====================================================

Q: What is the purpose of custom authentication in Oracle APEX?

A: The purpose of custom authentication in Oracle APEX is to provide a way to authenticate users using a custom authentication scheme that is not supported by the built-in authentication scheme. This can be useful in cases where you need to implement custom authentication logic, integrate with third-party systems, or meet specific security requirements.

Q: How do I create a custom authentication scheme in Oracle APEX?

A: To create a custom authentication scheme in Oracle APEX, you need to create a new package in your APEX application. This package will contain the custom authentication logic. You can then create a trigger that will call the custom authentication function and return the result to the APEX authentication engine.

Q: What is the difference between a custom authentication scheme and a built-in authentication scheme?

A: A custom authentication scheme is a custom implementation of the authentication logic that is not supported by the built-in authentication scheme. A built-in authentication scheme, on the other hand, is a pre-defined authentication scheme that is provided by Oracle APEX.

Q: How do I troubleshoot common issues with custom authentication in Oracle APEX?

A: To troubleshoot common issues with custom authentication in Oracle APEX, you can check the following:

ORA-06550: apex_authenticate_ldap must be ...: This error occurs when the apex_authenticate_ldap package is not compiled correctly. Make sure that the package is compiled correctly and that the authenticate function is implemented correctly.
ORA-06553: PLS-221: 'APEX_AUTHENTICATE_LDAP' is not a procedure or is undefined: This error occurs when the apex_authenticate_ldap package is not created correctly. Make sure that the package is created correctly and that the authenticate function is implemented correctly.

Q: Can I use custom authentication in Oracle APEX to implement multi-factor authentication?

A: Yes, you can use custom authentication in Oracle APEX to implement multi-factor authentication. You can create a custom authentication scheme that requires users to provide additional authentication factors such as a one-time password or a biometric scan.

Q: Can I use custom authentication in Oracle APEX to implement single sign-on?

A: Yes, you can use custom authentication in Oracle APEX to implement single sign-on. You can create a custom authentication scheme that allows users to access multiple applications using a single set of credentials.

Q: How do I configure the custom authentication scheme in Oracle APEX?

A: To configure the custom authentication scheme in Oracle APEX, you need to go to the APEX administration page and select the custom authentication scheme from the list of available authentication schemes.

Q: Can I use custom authentication in Oracle APEX to integrate with third-party systems?

A: Yes, you can use custom authentication in Oracle APEX to integrate with third-party systems. You can create a custom authentication scheme that uses the third-party system's authentication protocol.

Q: How do I ensure the security of my custom authentication scheme in Oracle APEX?

A: To ensure the security of your custom authentication scheme in Oracle APEX, you should:

Use secure coding practices: Use secure coding practices to prevent common web application vulnerabilities such as SQL injection and cross-site scripting (XSS).
Implement encryption: Implement encryption to protect sensitive data such as passwords and authentication tokens.
Use secure authentication protocols: Use secure authentication protocols such as OAuth and OpenID Connect to authenticate users.

Conclusion

Custom authentication in Oracle APEX using LDAP can be a complex task, but with the right guidance, it can be achieved successfully. In this article, we have explored the steps to implement custom authentication in APEX using LDAP, including creating a custom authentication scheme, implementing the custom authentication logic, creating a trigger to call the custom authentication function, and configuring the custom authentication scheme in APEX. We have also discussed troubleshooting common issues that may occur when implementing custom authentication in APEX.