fix(agentstack-server): fix #2138

[JanPokorny]

Summary

Linked Issues

Documentation

• No Docs Needed:

If this PR adds new feature or changes existing. Make sure documentation is adjusted accordingly. If the docs is not needed, please explain why.

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a bug related to OIDC provider configuration and validation within the agentstack-server. It introduces more flexible validation rules for OIDC metadata discovery and the insecure_transport setting. By making certain validations conditional and relaxing host-specific restrictions, the changes improve compatibility with various OIDC environments, particularly those utilizing non-HTTPS issuers or specific http:// scheme configurations for insecure transport.

Highlights

• OIDC Validation Logic: Modified the OIDC issuer discovery process to conditionally validate the jwks_uri and introspection_endpoint. These validations are now only performed if the OIDC provider's issuer URL uses an HTTPS scheme, preventing failures for HTTP-based issuers.
• Insecure Transport Configuration: Updated the validation for insecure_transport settings. The previous restriction that required the issuer host to be 'keycloak' when using an HTTP scheme has been removed. Now, insecure_transport is allowed solely based on the issuer URL using an http:// scheme.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Changelog

• apps/agentstack-server/src/agentstack_server/api/auth/auth.py
  • Made OIDC metadata validation for jwks_uri and introspection_endpoint conditional on the issuer scheme being HTTPS.
• apps/agentstack-server/src/agentstack_server/configuration.py
  • Removed the keycloak host restriction for insecure_transport when the issuer scheme is HTTP.

Activity

• No human activity has been recorded on this pull request yet.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for GitHub and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request adjusts the OIDC authentication flow to better support insecure transport for development environments by relaxing validation for http scheme issuers and conditionally skipping jwks_uri and introspection_endpoint validation for non-HTTPS issuers. However, this change introduces a significant security vulnerability by increasing the risk of sensitive credential leakage (e.g., client_secret) over unencrypted channels and potentially allowing the acceptance of malicious OIDC metadata due to skipped validations. Additionally, there's an opportunity to improve maintainability by refactoring duplicated code in the discovery logic.

[gemini-code-assist]

The application allows enabling insecure transport for OIDC authentication for any host. When insecure_transport is enabled and an HTTP issuer is used, sensitive credentials such as the client_secret will be transmitted over an unencrypted channel during token introspection and basic authentication. This exposes the credentials to interception by a man-in-the-middle attacker. The previous implementation restricted this to a specific host ('keycloak'), which likely limited the risk to internal traffic.

[gemini-code-assist]

The code skips validation of the JWKS URI and introspection endpoint when the OIDC issuer uses the 'http' scheme. This is done to support the insecure_transport configuration. However, by skipping these validations, the application may accept insecure or malformed metadata from an unencrypted source, which could be manipulated by an attacker to point to malicious endpoints.

[gemini-code-assist]

This conditional block is a duplicate of the one on lines 181-183. To adhere to the Don't Repeat Yourself (DRY) principle and improve maintainability, consider extracting this logic into a separate helper function. This would make the code cleaner and reduce redundancy.