jojo/tests/integration/api_actions_id_token_test.go
Mathieu Fenniak bdd2a1def7 fix: prevent actions workflows from generating OIDC tokens if not authorized in workflow (#12030)
When using Forgejo's `enable-openid-connect: true`, a URL is generated into the actions under `$ACTIONS_ID_TOKEN_REQUEST_URL` that can be used to generate a JWT for accessing third-party resources authenticated as the action executing in this server on this repo.  However, the endpoint of that url (`.../idtoken`) had unintentionally missed a `return` on an internal server error, and was missing a check that the action actually had `enable-openid-connect: true` on it.  As a result, it was possible to generate a JWT for accessing third-party resources from an action that wasn't expected to be generating JWTs.

In terms of real-world vulnerability, the most likely risk is that the JWT could be generated from a forked pull request.  By not using the `$ACTIONS_ID_TOKEN_REQUEST_URL` and instead going directly to the `.../idtoken` endpoint, and parsing a generated JWT response that will be mixed with an error response, it's possible to retrieve a JWT in a forked pull request.  It would require a slight misconfiguration on a third-party system to allow that JWT access, but it's a plausible risk.

As this is a feature in Forgejo 15 that hasn't been released, it will be fixed in-public.

## Checklist

The [contributor guide](https://forgejo.org/docs/next/contributor/) contains information that will be helpful to first time contributors. All work and communication must conform to Forgejo's [AI Agreement](https://codeberg.org/forgejo/governance/src/branch/main/AIAgreement.md). There also are a few [conditions for merging Pull Requests in Forgejo repositories](https://codeberg.org/forgejo/governance/src/branch/main/PullRequestsAgreement.md). You are also welcome to join the [Forgejo development chatroom](https://matrix.to/#/#forgejo-development:matrix.org).

### Tests for Go changes

(can be removed for JavaScript changes)

- I added test coverage for Go changes...
  - [ ] in their respective `*_test.go` for unit tests.
  - [x] in the `tests/integration` directory if it involves interactions with a live Forgejo server.
- I ran...
  - [x] `make pr-go` before pushing

### Documentation

- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [x] I did not document these changes and I do not expect someone else to do it.

### Release notes

- [ ] This change will be noticed by a Forgejo user or admin (feature, bug fix, performance, etc.). I suggest to include a release note for this change.
- [x] This change is not visible to a Forgejo user or admin (refactor, dependency upgrade, etc.). I think there is no need to add a release note for this change.
    - Feature is not yet released.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/12030
Reviewed-by: Andreas Ahlenstorf <aahlenst@noreply.codeberg.org>
Co-authored-by: Mathieu Fenniak <mathieu@fenniak.net>
Co-committed-by: Mathieu Fenniak <mathieu@fenniak.net>
2026-04-08 15:42:39 +02:00

191 lines
6.6 KiB
Go

// Copyright 2025 The Forgejo Authors. All rights reserved.
// SPDX-License-Identifier: GPL-3.0-or-later
package integration
import (
"crypto/rsa"
"encoding/base64"
"math/big"
"net/http"
"testing"
actions_model "forgejo.org/models/actions"
"forgejo.org/models/db"
"forgejo.org/modules/setting"
actions_service "forgejo.org/services/actions"
"forgejo.org/tests"
"github.com/golang-jwt/jwt/v5"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
type getTokenResponse struct {
Value string `json:"value"`
}
func prepareTestEnvActionsIDToken(t *testing.T) func() {
t.Helper()
f := tests.PrepareTestEnv(t, 1)
return f
}
func TestActionsIDToken(t *testing.T) {
defer prepareTestEnvActionsIDToken(t)()
task, err := actions_model.GetTaskByID(db.DefaultContext, 48)
if err != nil {
t.Fatal(err)
}
err = task.LoadAttributes(db.DefaultContext)
if err != nil {
t.Fatal(err)
}
gitCtx, err := actions_service.GenerateGiteaContext(task.Job.Run, task.Job)
require.NoError(t, err)
token, err := actions_service.CreateAuthorizationToken(task, gitCtx, true)
require.NoError(t, err)
tokenWithoutOIDCAccess, err := actions_service.CreateAuthorizationToken(task, gitCtx, false)
require.NoError(t, err)
// get JWKs information
req := NewRequest(t, "GET", "/api/actions/.well-known/keys")
resp := MakeRequest(t, req, http.StatusOK)
var jwks jwksResponse
DecodeJSON(t, resp, &jwks)
require.Len(t, jwks["keys"], 1)
key := jwks["keys"][0]
var exponent []byte
if exponent, err = base64.RawURLEncoding.DecodeString(key["e"]); err != nil {
t.Fatal(err)
}
var modulus []byte
if modulus, err = base64.RawURLEncoding.DecodeString(key["n"]); err != nil {
t.Fatal(err)
}
pubKey := rsa.PublicKey{
E: int(big.NewInt(0).SetBytes(exponent).Uint64()),
N: big.NewInt(0).SetBytes(modulus),
}
t.Run("success path", func(t *testing.T) {
doAssertions := func(aud string, claims map[string]any) {
assert.Equal(t, "user1", claims["actor"])
assert.Equal(t, aud, claims["aud"])
assert.Equal(t, setting.AppURL+"api/actions", claims["iss"])
assert.Equal(t, "refs/heads/master", claims["ref"])
assert.Equal(t, "false", claims["ref_protected"])
assert.Equal(t, "branch", claims["ref_type"])
assert.Equal(t, "user5/repo4", claims["repository"])
assert.Equal(t, "user5", claims["repository_owner"])
assert.Equal(t, "1", claims["run_attempt"])
assert.Equal(t, "792", claims["run_id"])
assert.Equal(t, "188", claims["run_number"])
assert.Equal(t, "c2d72f548424103f01ee1dc02889c1e2bff816b0", claims["sha"])
assert.Equal(t, "repo:user5/repo4:ref:refs/heads/master", claims["sub"])
assert.Equal(t, "artifact.yaml", claims["workflow"])
assert.Equal(t, "user5/repo4/.forgejo/workflows/artifact.yaml@refs/heads/master", claims["workflow_ref"])
}
// Default aud
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/792/idtoken?placeholder=true").AddTokenAuth(token)
resp = MakeRequest(t, req, http.StatusOK)
var getResponse getTokenResponse
DecodeJSON(t, resp, &getResponse)
claims := jwt.MapClaims{}
_, err = jwt.ParseWithClaims(getResponse.Value, claims, func(t *jwt.Token) (any, error) {
return &pubKey, nil
})
require.NoError(t, err)
doAssertions(setting.AppURL+"user5", claims)
// Custom aud
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/792/idtoken?placeholder=true&audience=testingAud").AddTokenAuth(token)
resp = MakeRequest(t, req, http.StatusOK)
DecodeJSON(t, resp, &getResponse)
claims = jwt.MapClaims{}
_, err = jwt.ParseWithClaims(getResponse.Value, claims, func(t *jwt.Token) (any, error) {
return &pubKey, nil
})
require.NoError(t, err)
doAssertions("testingAud", claims)
})
t.Run("with token that doesn't support OIDC", func(t *testing.T) {
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/792/idtoken?placeholder=true").AddTokenAuth(tokenWithoutOIDCAccess)
resp = MakeRequest(t, req, http.StatusInternalServerError)
assert.Contains(t, resp.Body.String(), "Error runner api parsing custom claims")
assert.NotContains(t, resp.Body.String(), "value") // must not leak an actual `getTokenResponse`
})
t.Run("with no auth header", func(t *testing.T) {
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/792/idtoken?placeholder=true&audience=testingAud")
resp = MakeRequest(t, req, http.StatusUnauthorized)
assert.Contains(t, resp.Body.String(), "Bad authorization header")
})
t.Run("with bad token format", func(t *testing.T) {
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/792/idtoken?placeholder=true&audience=testingAud").AddTokenAuth("1234567")
resp = MakeRequest(t, req, http.StatusInternalServerError)
assert.Contains(t, resp.Body.String(), "Error runner api parsing authorization token")
})
t.Run("with invalid task", func(t *testing.T) {
task, err := actions_model.GetTaskByID(db.DefaultContext, 48)
if err != nil {
t.Fatal(err)
}
err = task.LoadAttributes(db.DefaultContext)
if err != nil {
t.Fatal(err)
}
// Change ID to be invalid
task.ID = 123456
gitCtx, err := actions_service.GenerateGiteaContext(task.Job.Run, task.Job)
require.NoError(t, err)
token, err := actions_service.CreateAuthorizationToken(task, gitCtx, true)
require.NoError(t, err)
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/abcde/idtoken?placeholder=true&audience=testingAud").AddTokenAuth(token)
resp = MakeRequest(t, req, http.StatusInternalServerError)
assert.Contains(t, resp.Body.String(), "Error runner api getting task by ID")
})
t.Run("with task that is not running", func(t *testing.T) {
task, err := actions_model.GetTaskByID(db.DefaultContext, 49)
if err != nil {
t.Fatal(err)
}
err = task.LoadAttributes(db.DefaultContext)
if err != nil {
t.Fatal(err)
}
gitCtx, err := actions_service.GenerateGiteaContext(task.Job.Run, task.Job)
require.NoError(t, err)
token, err := actions_service.CreateAuthorizationToken(task, gitCtx, true)
require.NoError(t, err)
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/abcde/idtoken?placeholder=true&audience=testingAud").AddTokenAuth(token)
resp = MakeRequest(t, req, http.StatusInternalServerError)
assert.Contains(t, resp.Body.String(), "Error runner api getting task: task is not running")
})
t.Run("with mismatched run ID", func(t *testing.T) {
req = NewRequest(t, "GET", "/api/actions/_apis/pipelines/workflows/123/idtoken?placeholder=true&audience=testingAud").AddTokenAuth(token)
resp = MakeRequest(t, req, http.StatusBadRequest)
assert.Contains(t, resp.Body.String(), "run-id does not match")
})
}