forgejo/services/actions/auth.go
Rowan Bohde ddabba5f89
allow the actions user to login via the jwt token (#32527)
We have some actions that leverage the Gitea API that began receiving
401 errors, with a message that the user was not found. These actions
use the `ACTIONS_RUNTIME_TOKEN` env var in the actions job to
authenticate with the Gitea API. The format of this env var in actions
jobs changed with go-gitea/gitea/pull/28885 to be a JWT (with a
corresponding update to `act_runner`) Since it was a JWT, the OAuth
parsing logic attempted to parse it as an OAuth token, and would return
user not found, instead of falling back to look up the running task and
assigning it to the actions user.

Make ACTIONS_RUNTIME_TOKEN in action runners could be used,
attempting to parse Oauth JWTs. The code to parse potential old
`ACTION_RUNTIME_TOKEN` was kept in case someone is running an older
version of act_runner that doesn't support the Actions JWT.

(cherry picked from commit 407b6e6dfc7ee9ebb8a16c7f1a786e4c24d0516e)

Conflicts:
	services/auth/oauth2.go
  trivial context conflicts because OAuth2 scopes are in Forgejo and
  not yet in Gitea
2024-11-24 10:41:56 +00:00

107 lines
2.3 KiB
Go

// Copyright 2024 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package actions
import (
"fmt"
"net/http"
"strings"
"time"
"code.gitea.io/gitea/modules/json"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
"github.com/golang-jwt/jwt/v5"
)
type actionsClaims struct {
jwt.RegisteredClaims
Scp string `json:"scp"`
TaskID int64
RunID int64
JobID int64
Ac string `json:"ac"`
}
type actionsCacheScope struct {
Scope string
Permission actionsCachePermission
}
type actionsCachePermission int
const (
actionsCachePermissionRead = 1 << iota
actionsCachePermissionWrite
)
func CreateAuthorizationToken(taskID, runID, jobID int64) (string, error) {
now := time.Now()
ac, err := json.Marshal(&[]actionsCacheScope{
{
Scope: "",
Permission: actionsCachePermissionWrite,
},
})
if err != nil {
return "", err
}
claims := actionsClaims{
RegisteredClaims: jwt.RegisteredClaims{
ExpiresAt: jwt.NewNumericDate(now.Add(24 * time.Hour)),
NotBefore: jwt.NewNumericDate(now),
},
Scp: fmt.Sprintf("Actions.Results:%d:%d", runID, jobID),
Ac: string(ac),
TaskID: taskID,
RunID: runID,
JobID: jobID,
}
token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
tokenString, err := token.SignedString(setting.GetGeneralTokenSigningSecret())
if err != nil {
return "", err
}
return tokenString, nil
}
func ParseAuthorizationToken(req *http.Request) (int64, error) {
h := req.Header.Get("Authorization")
if h == "" {
return 0, nil
}
parts := strings.SplitN(h, " ", 2)
if len(parts) != 2 {
log.Error("split token failed: %s", h)
return 0, fmt.Errorf("split token failed")
}
return TokenToTaskID(parts[1])
}
// TokenToTaskID returns the TaskID associated with the provided JWT token
func TokenToTaskID(token string) (int64, error) {
parsedToken, err := jwt.ParseWithClaims(token, &actionsClaims{}, func(t *jwt.Token) (any, error) {
if _, ok := t.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("unexpected signing method: %v", t.Header["alg"])
}
return setting.GetGeneralTokenSigningSecret(), nil
})
if err != nil {
return 0, err
}
c, ok := parsedToken.Claims.(*actionsClaims)
if !parsedToken.Valid || !ok {
return 0, fmt.Errorf("invalid token claim")
}
return c.TaskID, nil
}