jojo/services/auth/method/util.go
Mathieu Fenniak ef5479af71 refactor: split "basic" and "oauth2" authentication impl into smaller single-purpose components (#12236)
Forgejo's `basic` and `oauth2` authentication methods perform five distinct types of authentication:
- Username and password authentication
- Personal access tokens
- OAuth2 access tokens
- Forgejo Action's `${{ forgejo.token }}` -- task-based static tokens
- Forgejo Action's `${{ env.ACTIONS_RUNTIME_TOKEN }}` JWT, which is the authentication method used for `upload-artifact` (mirroring GitHub's implementation)

`basic` and `oauth2` both supported almost all of these methods, resulting in quite a bit of code duplication between them.  This PR splits personal access tokens into `access_token.go`, Action's task-based tokens into `action_task_token.go`, and Action's JWT tokens into `action_runtime_token.go`.

**Note:** There is one peculiar side-effect that is worth discussing.  Previously, `Authorization: Basic ...` was handled by one complex code path in basic.go, and `Authorization: Bearer ...` was handled by another in oauth2.go, and if authorization failed and a 401 was returned, a single error message would be returned to the user.  Now, as multiple authorization methods may look at `Authorization: Basic ...` and provide their own reason why authorization didn't work, a 401 response has multiple reasons for a lack of authorization listed:

```
401 Unauthorized
...

failure to authenticate with oauth2 access token: not a JWT
Basic authorization is not allowed while having security keys enrolled
access token does not exist [sha: notpassword]
task with token "notpassword": resource does not exist
```

A couple tests have been adapted to check that the result contains their expected response, rather than is equal-to or prefixed-with their expected result.  This is caused by the "auth group" joining together any "invalid credentials" errors, and, to a certain extent it is useful to understand why the authorization request failed.  But it's a bit obscure as well.

## 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

- I added test coverage for Go changes...
  - [ ] in their respective `*_test.go` for unit tests.
  - [ ] in the `tests/integration` directory if it involves interactions with a live Forgejo server.
  - Relying on integration testing for regression checks.
- 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.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/12236
Reviewed-by: Andreas Ahlenstorf <aahlenst@noreply.codeberg.org>
2026-04-24 18:19:58 +02:00

71 lines
2.4 KiB
Go

// Copyright 2026 The Forgejo Authors. All rights reserved.
// SPDX-License-Identifier: GPL-3.0-or-later
package method
import (
"net/http"
"strings"
"forgejo.org/modules/base"
"forgejo.org/modules/log"
"forgejo.org/modules/optional"
"forgejo.org/modules/setting"
"forgejo.org/modules/util"
)
func tokenFromForm(req *http.Request) optional.Option[string] {
_ = req.ParseForm()
if !setting.DisableQueryAuthToken {
// Check token.
if token := req.Form.Get("token"); token != "" {
return optional.Some(token)
}
// Check access token.
if token := req.Form.Get("access_token"); token != "" {
return optional.Some(token)
}
} else if req.Form.Get("token") != "" || req.Form.Get("access_token") != "" {
log.Warn("API token sent in query string but DISABLE_QUERY_AUTH_TOKEN=true")
}
return optional.None[string]()
}
func tokenFromAuthorizationBearer(req *http.Request) optional.Option[string] {
authorization := req.Header.Get("Authorization")
if len(authorization) != 0 {
auths := strings.Fields(authorization)
if len(auths) == 2 && (util.ASCIIEqualFold(auths[0], "token") || util.ASCIIEqualFold(auths[0], "bearer")) {
return optional.Some(auths[1])
}
}
return optional.None[string]()
}
func tokenFromAuthorizationBasic(req *http.Request) optional.Option[string] {
authorization := req.Header.Get("Authorization")
if len(authorization) != 0 {
auths := strings.SplitN(authorization, " ", 2)
if len(auths) == 2 && strings.ToLower(auths[0]) == "basic" {
uname, passwd, err := base.BasicAuthDecode(auths[1])
if err != nil {
// Client provided a `Authorization: Basic ...`, but then [...] either couldn't be base64 decoded, or
// didn't contain a ":" for username/password separation. If we return `None`, it'll indicate to the
// caller that `Authorization: Basic [...]` wasn't present and skip authentication, so intead we'll
// return Some with an empty token to trigger a 401 error.
log.Debug("unexpected error in BasicAuthDecode(%q): %s", auths[1], err)
return optional.Some("")
}
// Usually we'll use the password as the access token (or oauth token), but if the password is empty or
// `x-oauth-basic`, we'll use the username as a token. This behaviour is inherited from GitHub's OAuth Git
// over HTTPS behaviour.
if len(passwd) == 0 || passwd == "x-oauth-basic" {
return optional.Some(uname)
}
return optional.Some(passwd)
}
}
return optional.None[string]()
}