forgejo/services/auth/reverseproxy.go
Lunny Xiao 900e158064
refactor auth interface to return error when verify failure (#22119) (#22259)
backport #22119

This PR changed the Auth interface signature from `Verify(http
*http.Request, w http.ResponseWriter, store DataStore, sess
SessionStore) *user_model.User`
to 
`Verify(http *http.Request, w http.ResponseWriter, store DataStore, sess
SessionStore) (*user_model.User, error)`.

There is a new return argument `error` which means the verification
condition matched but verify process failed, we should stop the auth
process.

Before this PR, when return a `nil` user, we don't know the reason why
it returned `nil`. If the match condition is not satisfied or it
verified failure? For these two different results, we should have
different handler. If the match condition is not satisfied, we should
try next auth method and if there is no more auth method, it's an
anonymous user. If the condition matched but verify failed, the auth
process should be stop and return immediately.

This will fix #20563

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>
Co-authored-by: Jason Song <i@wolfogre.com>
2022-12-29 13:50:09 +08:00

179 lines
6 KiB
Go

// Copyright 2014 The Gogs Authors. All rights reserved.
// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package auth
import (
"net/http"
"strings"
user_model "code.gitea.io/gitea/models/user"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/util"
"code.gitea.io/gitea/modules/web/middleware"
"code.gitea.io/gitea/services/mailer"
gouuid "github.com/google/uuid"
)
// Ensure the struct implements the interface.
var (
_ Method = &ReverseProxy{}
_ Named = &ReverseProxy{}
)
// ReverseProxyMethodName is the constant name of the ReverseProxy authentication method
const ReverseProxyMethodName = "reverse_proxy"
// ReverseProxy implements the Auth interface, but actually relies on
// a reverse proxy for authentication of users.
// On successful authentication the proxy is expected to populate the username in the
// "setting.ReverseProxyAuthUser" header. Optionally it can also populate the email of the
// user in the "setting.ReverseProxyAuthEmail" header.
type ReverseProxy struct{}
// getUserName extracts the username from the "setting.ReverseProxyAuthUser" header
func (r *ReverseProxy) getUserName(req *http.Request) string {
return strings.TrimSpace(req.Header.Get(setting.ReverseProxyAuthUser))
}
// Name represents the name of auth method
func (r *ReverseProxy) Name() string {
return ReverseProxyMethodName
}
// getUserFromAuthUser extracts the username from the "setting.ReverseProxyAuthUser" header
// of the request and returns the corresponding user object for that name.
// Verification of header data is not performed as it should have already been done by
// the reverse proxy.
// If a username is available in the "setting.ReverseProxyAuthUser" header an existing
// user object is returned (populated with username or email found in header).
// Returns nil if header is empty.
func (r *ReverseProxy) getUserFromAuthUser(req *http.Request) (*user_model.User, error) {
username := r.getUserName(req)
if len(username) == 0 {
return nil, nil
}
log.Trace("ReverseProxy Authorization: Found username: %s", username)
user, err := user_model.GetUserByName(req.Context(), username)
if err != nil {
if !user_model.IsErrUserNotExist(err) || !r.isAutoRegisterAllowed() {
log.Error("GetUserByName: %v", err)
return nil, err
}
user = r.newUser(req)
}
return user, nil
}
// getEmail extracts the email from the "setting.ReverseProxyAuthEmail" header
func (r *ReverseProxy) getEmail(req *http.Request) string {
return strings.TrimSpace(req.Header.Get(setting.ReverseProxyAuthEmail))
}
// getUserFromAuthEmail extracts the username from the "setting.ReverseProxyAuthEmail" header
// of the request and returns the corresponding user object for that email.
// Verification of header data is not performed as it should have already been done by
// the reverse proxy.
// If an email is available in the "setting.ReverseProxyAuthEmail" header an existing
// user object is returned (populated with the email found in header).
// Returns nil if header is empty or if "setting.EnableReverseProxyEmail" is disabled.
func (r *ReverseProxy) getUserFromAuthEmail(req *http.Request) *user_model.User {
if !setting.Service.EnableReverseProxyEmail {
return nil
}
email := r.getEmail(req)
if len(email) == 0 {
return nil
}
log.Trace("ReverseProxy Authorization: Found email: %s", email)
user, err := user_model.GetUserByEmail(email)
if err != nil {
// Do not allow auto-registration, we don't have a username here
if !user_model.IsErrUserNotExist(err) {
log.Error("GetUserByEmail: %v", err)
}
return nil
}
return user
}
// Verify attempts to load a user object based on headers sent by the reverse proxy.
// First it will attempt to load it based on the username (see docs for getUserFromAuthUser),
// and failing that it will attempt to load it based on the email (see docs for getUserFromAuthEmail).
// Returns nil if the headers are empty or the user is not found.
func (r *ReverseProxy) Verify(req *http.Request, w http.ResponseWriter, store DataStore, sess SessionStore) (*user_model.User, error) {
user, err := r.getUserFromAuthUser(req)
if err != nil {
return nil, err
}
if user == nil {
user = r.getUserFromAuthEmail(req)
if user == nil {
return nil, nil
}
}
// Make sure requests to API paths, attachment downloads, git and LFS do not create a new session
if !middleware.IsAPIPath(req) && !isAttachmentDownload(req) && !isGitRawReleaseOrLFSPath(req) {
if sess != nil && (sess.Get("uid") == nil || sess.Get("uid").(int64) != user.ID) {
handleSignIn(w, req, sess, user)
}
}
store.GetData()["IsReverseProxy"] = true
log.Trace("ReverseProxy Authorization: Logged in user %-v", user)
return user, nil
}
// isAutoRegisterAllowed checks if EnableReverseProxyAutoRegister setting is true
func (r *ReverseProxy) isAutoRegisterAllowed() bool {
return setting.Service.EnableReverseProxyAutoRegister
}
// newUser creates a new user object for the purpose of automatic registration
// and populates its name and email with the information present in request headers.
func (r *ReverseProxy) newUser(req *http.Request) *user_model.User {
username := r.getUserName(req)
if len(username) == 0 {
return nil
}
email := gouuid.New().String() + "@localhost"
if setting.Service.EnableReverseProxyEmail {
webAuthEmail := req.Header.Get(setting.ReverseProxyAuthEmail)
if len(webAuthEmail) > 0 {
email = webAuthEmail
}
}
var fullname string
if setting.Service.EnableReverseProxyFullName {
fullname = req.Header.Get(setting.ReverseProxyAuthFullName)
}
user := &user_model.User{
Name: username,
Email: email,
FullName: fullname,
}
overwriteDefault := user_model.CreateUserOverwriteOptions{
IsActive: util.OptionalBoolTrue,
}
if err := user_model.CreateUser(user, &overwriteDefault); err != nil {
// FIXME: should I create a system notice?
log.Error("CreateUser: %v", err)
return nil
}
mailer.SendRegisterNotifyMail(user)
return user
}