# Implement OAuth2 Dynamic Client Registration (RFC 7591/7592)
This PR implements OAuth2 Dynamic Client Registration according to RFC 7591 and Client Configuration Management according to RFC 7592. These standards allow OAuth2 clients to register themselves programmatically with Coder as an authorization server.
Key changes include:
1. Added database schema extensions to support RFC 7591/7592 fields in the `oauth2_provider_apps` table
2. Implemented `/oauth2/register` endpoint for dynamic client registration (RFC 7591)
3. Added client configuration management endpoints (RFC 7592):
- GET/PUT/DELETE `/oauth2/clients/{client_id}`
- Registration access token validation middleware
4. Added comprehensive validation for OAuth2 client metadata:
- URI validation with support for custom schemes for native apps
- Grant type and response type validation
- Token endpoint authentication method validation
5. Enhanced developer documentation with:
- RFC compliance guidelines
- Testing best practices to avoid race conditions
- Systematic debugging approaches for OAuth2 implementations
The implementation follows security best practices from the RFCs, including proper token handling, secure defaults, and appropriate error responses. This enables third-party applications to integrate with Coder's OAuth2 provider capabilities programmatically.
This PR provides two commands:
* `coder prebuilds pause`
* `coder prebuilds resume`
These allow the suspension of all prebuilds activity, intended for use
if prebuilds are misbehaving.
add a new section specifically about how to disable path-based apps to
the security best practices doc
## todo
- [x] copy review
- [x] cross-linking
---------
Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
Co-authored-by: Dean Sheather <dean@deansheather.com>
## Summary
This PR implements critical MCP OAuth2 compliance features for Coder's authorization server, adding PKCE support, resource parameter handling, and OAuth2 server metadata discovery. This brings Coder's OAuth2 implementation significantly closer to production readiness for MCP (Model Context Protocol)
integrations.
## What's Added
### OAuth2 Authorization Server Metadata (RFC 8414)
- Add `/.well-known/oauth-authorization-server` endpoint for automatic client discovery
- Returns standardized metadata including supported grant types, response types, and PKCE methods
- Essential for MCP client compatibility and OAuth2 standards compliance
### PKCE Support (RFC 7636)
- Implement Proof Key for Code Exchange with S256 challenge method
- Add `code_challenge` and `code_challenge_method` parameters to authorization flow
- Add `code_verifier` validation in token exchange
- Provides enhanced security for public clients (mobile apps, CLIs)
### Resource Parameter Support (RFC 8707)
- Add `resource` parameter to authorization and token endpoints
- Store resource URI and bind tokens to specific audiences
- Critical for MCP's resource-bound token model
### Enhanced OAuth2 Error Handling
- Add OAuth2-compliant error responses with proper error codes
- Use standard error format: `{"error": "code", "error_description": "details"}`
- Improve error consistency across OAuth2 endpoints
### Authorization UI Improvements
- Fix authorization flow to use POST-based consent instead of GET redirects
- Remove dependency on referer headers for security decisions
- Improve CSRF protection with proper state parameter validation
## Why This Matters
**For MCP Integration:** MCP requires OAuth2 authorization servers to support PKCE, resource parameters, and metadata discovery. Without these features, MCP clients cannot securely authenticate with Coder.
**For Security:** PKCE prevents authorization code interception attacks, especially critical for public clients. Resource binding ensures tokens are only valid for intended services.
**For Standards Compliance:** These are widely adopted OAuth2 extensions that improve interoperability with modern OAuth2 clients.
## Database Changes
- **Migration 000343:** Adds `code_challenge`, `code_challenge_method`, `resource_uri` to `oauth2_provider_app_codes`
- **Migration 000343:** Adds `audience` field to `oauth2_provider_app_tokens` for resource binding
- **Audit Updates:** New OAuth2 fields properly tracked in audit system
- **Backward Compatibility:** All changes maintain compatibility with existing OAuth2 flows
## Test Coverage
- Comprehensive PKCE test suite in `coderd/identityprovider/pkce_test.go`
- OAuth2 metadata endpoint tests in `coderd/oauth2_metadata_test.go`
- Integration tests covering PKCE + resource parameter combinations
- Negative tests for invalid PKCE verifiers and malformed requests
## Testing Instructions
```bash
# Run the comprehensive OAuth2 test suite
./scripts/oauth2/test-mcp-oauth2.sh
Manual Testing with Interactive Server
# Start Coder in development mode
./scripts/develop.sh
# In another terminal, set up test app and run interactive flow
eval $(./scripts/oauth2/setup-test-app.sh)
./scripts/oauth2/test-manual-flow.sh
# Opens browser with OAuth2 flow, handles callback automatically
# Clean up when done
./scripts/oauth2/cleanup-test-app.sh
Individual Component Testing
# Test metadata endpoint
curl -s http://localhost:3000/.well-known/oauth-authorization-server | jq .
# Test PKCE generation
./scripts/oauth2/generate-pkce.sh
# Run specific test suites
go test -v ./coderd/identityprovider -run TestVerifyPKCE
go test -v ./coderd -run TestOAuth2AuthorizationServerMetadata
```
### Breaking Changes
None. All changes maintain backward compatibility with existing OAuth2 flows.
---
Change-Id: Ifbd0d9a543d545f9f56ecaa77ff2238542ff954a
Signed-off-by: Thomas Kosiewski <tk@coder.com>
## Description
This PR adds a warning to the prebuilds documentation about
incompatibility with Workspace schedule (autostart/autostop), dormancy,
and DevContainers. These configurations can interfere with prebuild
behavior and should be avoided for now.
Preview:
Deletion of data is uncommon in our database, so the introduction of sub agents
and the deletion of them introduced issues with foreign key assumptions, as can
be seen in coder/internal#685. We could have only addressed the specific case by
allowing cascade deletion of stats as well as handling in the stats collector,
but it's unclear how many more such edge-cases we could run into.
In this change, we mark the rows as deleted via boolean instead, and filter them
out in all relevant queries.
Fixescoder/internal#685
Adds database migrations required for the Tasks feature.
There's a slight difference between the migrations in this PR and the
RFC: this PR adds `NOT NULL` constraints to the `has_ai_task` columns.
It was an oversight on my part when I wrote the RFC - I assumed the
`DEFAULT FALSE` value would make the columns implicitly NOT NULL, but
that's not the case with Postgres. We have no use for the NULL value.
The `DEFAULT FALSE` statement ensures that the migration will pass even
when there are existing rows in the template version and workspace
builds tables, so there's no danger in adding the `NOT NULL`
constraints.
As part of an information architecture overhaul, this PR reorganizes the
About section and adds a Support section (but not content to it yet)
[preview](https://coder.com/docs/@docs-ia-about/about)
this PR is intentionally limited in scope so that we can ship meaningful
changes faster and followup PRs should include:
- [ ] edit + overhaul the About page
- [ ] decide on the `start` directory
- [ ] ~screenshots page updates~ (this should happen July or later)
redirects PR: https://github.com/coder/coder.com/pull/944
---------
Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
Following some issues we discovered on dogfood after merging #17878, we
think `prompt=consent` is required for refresh tokens to be sent by
Google every time you sign in.
## Summary
This PR introduces support for expiration policies in prebuilds. The TTL
(time-to-live) is retrieved from the Terraform configuration
([terraform-provider-coder
PR](https://github.com/coder/terraform-provider-coder/pull/404)):
```
prebuilds = {
instances = 2
expiration_policy {
ttl = 86400
}
}
```
**Note**: Since there is no need for precise TTL enforcement down to the
second, in this implementation expired prebuilds are handled in a single
reconciliation cycle: they are deleted, and new instances are created
only if needed to match the desired count.
## Changes
* The outcome of a reconciliation cycle is now expressed as a slice of
reconciliation actions, instead of a single aggregated action.
* Adjusted reconciliation logic to delete expired prebuilds and
guarantee that the number of desired instances is correct.
* Updated relevant data structures and methods to support expiration
policies parameters.
* Added documentation to `Prebuilt workspaces` page
* Update `terraform-provider-coder` to version 2.5.0:
https://github.com/coder/terraform-provider-coder/releases/tag/v2.5.0
Depends on: https://github.com/coder/terraform-provider-coder/pull/404
Fixes: https://github.com/coder/coder/issues/17916
We probably shouldn't be suggesting `ignore_changes = all`. Only the
attributes which cause drift in prebuilds should be ignored; everything
else can behave as normal.
---------
Signed-off-by: Danny Kopping <dannykopping@gmail.com>
Co-authored-by: Edward Angert <EdwardAngert@users.noreply.github.com>
These items came up in an internal "bug bash" session yesterday.
@EdwardAngert note: I've reverted to the "transparent" phrasing; the
current docs confused a couple folks yesterday, and I feel that
"transparent" is clearly understood in this context.
---------
Signed-off-by: Danny Kopping <dannykopping@gmail.com>
Co-authored-by: Edward Angert <EdwardAngert@users.noreply.github.com>
Closes https://github.com/coder/internal/issues/369
We can't know whether a replacement (i.e. drift of terraform state
leading to a resource needing to be deleted/recreated) will take place
apriori; we can only detect it at `plan` time, because the provider
decides whether a resource must be replaced and it cannot be inferred
through static analysis of the template.
**This is likely to be the most common gotcha with using prebuilds,
since it requires a slight template modification to use prebuilds
effectively**, so let's head this off before it's an issue for
customers.
Drift details will now be logged in the workspace build logs:
Plus a notification will be sent to template admins when this situation
arises:
A new metric - `coderd_prebuilt_workspaces_resource_replacements_total`
- will also increment each time a workspace encounters replacements.
We only track _that_ a resource replacement occurred, not how many. Just
one is enough to ruin a prebuild, but we can't know apriori which
replacement would cause this.
For example, say we have 2 replacements: a `docker_container` and a
`null_resource`; we don't know which one might
cause an issue (or indeed if either would), so we just track the
replacement.
---------
Signed-off-by: Danny Kopping <dannykopping@gmail.com>
closes#17706
Clarify that:
1. URL query parameters work without experiment flag
2. The 'populate recently used parameters' feature still requires the
auto-fill-parameters experiment flag
Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
This change documents the early access dev containers integration and
how to enable it, what features are available and what limitations exist
at the time of writing.
---------
Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
closes#17375
from @ericpaulsen
> a prospect recently inquired about how our OAuth integration with
GitLab works, and I realized we do not have any information on
`GIT_ASKPASS` is used to retreive the OAuth token for users when they
run `git` operations.
Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
Fixes docs troubleshooting language around low MTU. In fact, we see
conenctions hanging rather than just showing low performance, since
packets are dropped rather than fragmented.
---------
Co-authored-by: Edward Angert <EdwardAngert@users.noreply.github.com>
Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
