forgejo/modules/auth/oauth2/oauth2.go
Martin Michaelis 55eb1745bd
OAuth2 auto-register (#5123)
* Refactored handleOAuth2SignIn in routers/user/auth.go

The function handleOAuth2SignIn was called twice but some code path could only
be reached by one of the invocations. Moved the unnecessary code path out of
handleOAuth2SignIn.


* Refactored user creation

There was common code to create a user and display the correct error message.
And after the creation the only user should be an admin and if enabled a
confirmation email should be sent. This common code is now abstracted into
two functions and a helper function to call both.

* Added auto-register for OAuth2 users

If enabled new OAuth2 users will be registered with their OAuth2 details.
The UserID, Name and Email fields from the gothUser are used.
Therefore the OpenID Connect provider needs additional scopes to return
the coresponding claims.

* Added error for missing fields in OAuth2 response

* Linking and auto linking on oauth2 registration

* Set default username source to nickname

* Add automatic oauth2 scopes for github and google

* Add hint to change the openid connect scopes if fields are missing

* Extend info about auto linking security risk

Co-authored-by: Viktor Kuzmin <kvaster@gmail.com>
Signed-off-by: Martin Michaelis <code@mgjm.de>
2021-04-14 14:02:12 +02:00

300 lines
9.8 KiB
Go

// Copyright 2017 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 oauth2
import (
"net/http"
"net/url"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
uuid "github.com/google/uuid"
"github.com/lafriks/xormstore"
"github.com/markbates/goth"
"github.com/markbates/goth/gothic"
"github.com/markbates/goth/providers/bitbucket"
"github.com/markbates/goth/providers/discord"
"github.com/markbates/goth/providers/dropbox"
"github.com/markbates/goth/providers/facebook"
"github.com/markbates/goth/providers/gitea"
"github.com/markbates/goth/providers/github"
"github.com/markbates/goth/providers/gitlab"
"github.com/markbates/goth/providers/google"
"github.com/markbates/goth/providers/mastodon"
"github.com/markbates/goth/providers/nextcloud"
"github.com/markbates/goth/providers/openidConnect"
"github.com/markbates/goth/providers/twitter"
"github.com/markbates/goth/providers/yandex"
"xorm.io/xorm"
)
var (
sessionUsersStoreKey = "gitea-oauth2-sessions"
providerHeaderKey = "gitea-oauth2-provider"
)
// CustomURLMapping describes the urls values to use when customizing OAuth2 provider URLs
type CustomURLMapping struct {
AuthURL string
TokenURL string
ProfileURL string
EmailURL string
}
// Init initialize the setup of the OAuth2 library
func Init(x *xorm.Engine) error {
store, err := xormstore.NewOptions(x, xormstore.Options{
TableName: "oauth2_session",
}, []byte(sessionUsersStoreKey))
if err != nil {
return err
}
// according to the Goth lib:
// set the maxLength of the cookies stored on the disk to a larger number to prevent issues with:
// securecookie: the value is too long
// when using OpenID Connect , since this can contain a large amount of extra information in the id_token
// Note, when using the FilesystemStore only the session.ID is written to a browser cookie, so this is explicit for the storage on disk
store.MaxLength(setting.OAuth2.MaxTokenLength)
gothic.Store = store
gothic.SetState = func(req *http.Request) string {
return uuid.New().String()
}
gothic.GetProviderName = func(req *http.Request) (string, error) {
return req.Header.Get(providerHeaderKey), nil
}
return nil
}
// Auth OAuth2 auth service
func Auth(provider string, request *http.Request, response http.ResponseWriter) error {
// not sure if goth is thread safe (?) when using multiple providers
request.Header.Set(providerHeaderKey, provider)
// don't use the default gothic begin handler to prevent issues when some error occurs
// normally the gothic library will write some custom stuff to the response instead of our own nice error page
//gothic.BeginAuthHandler(response, request)
url, err := gothic.GetAuthURL(response, request)
if err == nil {
http.Redirect(response, request, url, http.StatusTemporaryRedirect)
}
return err
}
// ProviderCallback handles OAuth callback, resolve to a goth user and send back to original url
// this will trigger a new authentication request, but because we save it in the session we can use that
func ProviderCallback(provider string, request *http.Request, response http.ResponseWriter) (goth.User, error) {
// not sure if goth is thread safe (?) when using multiple providers
request.Header.Set(providerHeaderKey, provider)
user, err := gothic.CompleteUserAuth(response, request)
if err != nil {
return user, err
}
return user, nil
}
// RegisterProvider register a OAuth2 provider in goth lib
func RegisterProvider(providerName, providerType, clientID, clientSecret, openIDConnectAutoDiscoveryURL string, customURLMapping *CustomURLMapping) error {
provider, err := createProvider(providerName, providerType, clientID, clientSecret, openIDConnectAutoDiscoveryURL, customURLMapping)
if err == nil && provider != nil {
goth.UseProviders(provider)
}
return err
}
// RemoveProvider removes the given OAuth2 provider from the goth lib
func RemoveProvider(providerName string) {
delete(goth.GetProviders(), providerName)
}
// ClearProviders clears all OAuth2 providers from the goth lib
func ClearProviders() {
goth.ClearProviders()
}
// used to create different types of goth providers
func createProvider(providerName, providerType, clientID, clientSecret, openIDConnectAutoDiscoveryURL string, customURLMapping *CustomURLMapping) (goth.Provider, error) {
callbackURL := setting.AppURL + "user/oauth2/" + url.PathEscape(providerName) + "/callback"
var provider goth.Provider
var err error
switch providerType {
case "bitbucket":
provider = bitbucket.New(clientID, clientSecret, callbackURL, "account")
case "dropbox":
provider = dropbox.New(clientID, clientSecret, callbackURL)
case "facebook":
provider = facebook.New(clientID, clientSecret, callbackURL, "email")
case "github":
authURL := github.AuthURL
tokenURL := github.TokenURL
profileURL := github.ProfileURL
emailURL := github.EmailURL
if customURLMapping != nil {
if len(customURLMapping.AuthURL) > 0 {
authURL = customURLMapping.AuthURL
}
if len(customURLMapping.TokenURL) > 0 {
tokenURL = customURLMapping.TokenURL
}
if len(customURLMapping.ProfileURL) > 0 {
profileURL = customURLMapping.ProfileURL
}
if len(customURLMapping.EmailURL) > 0 {
emailURL = customURLMapping.EmailURL
}
}
scopes := []string{}
if setting.OAuth2Client.EnableAutoRegistration {
scopes = append(scopes, "user:email")
}
provider = github.NewCustomisedURL(clientID, clientSecret, callbackURL, authURL, tokenURL, profileURL, emailURL, scopes...)
case "gitlab":
authURL := gitlab.AuthURL
tokenURL := gitlab.TokenURL
profileURL := gitlab.ProfileURL
if customURLMapping != nil {
if len(customURLMapping.AuthURL) > 0 {
authURL = customURLMapping.AuthURL
}
if len(customURLMapping.TokenURL) > 0 {
tokenURL = customURLMapping.TokenURL
}
if len(customURLMapping.ProfileURL) > 0 {
profileURL = customURLMapping.ProfileURL
}
}
provider = gitlab.NewCustomisedURL(clientID, clientSecret, callbackURL, authURL, tokenURL, profileURL, "read_user")
case "gplus": // named gplus due to legacy gplus -> google migration (Google killed Google+). This ensures old connections still work
scopes := []string{"email"}
if setting.OAuth2Client.UpdateAvatar || setting.OAuth2Client.EnableAutoRegistration {
scopes = append(scopes, "profile")
}
provider = google.New(clientID, clientSecret, callbackURL, scopes...)
case "openidConnect":
if provider, err = openidConnect.New(clientID, clientSecret, callbackURL, openIDConnectAutoDiscoveryURL, setting.OAuth2Client.OpenIDConnectScopes...); err != nil {
log.Warn("Failed to create OpenID Connect Provider with name '%s' with url '%s': %v", providerName, openIDConnectAutoDiscoveryURL, err)
}
case "twitter":
provider = twitter.NewAuthenticate(clientID, clientSecret, callbackURL)
case "discord":
provider = discord.New(clientID, clientSecret, callbackURL, discord.ScopeIdentify, discord.ScopeEmail)
case "gitea":
authURL := gitea.AuthURL
tokenURL := gitea.TokenURL
profileURL := gitea.ProfileURL
if customURLMapping != nil {
if len(customURLMapping.AuthURL) > 0 {
authURL = customURLMapping.AuthURL
}
if len(customURLMapping.TokenURL) > 0 {
tokenURL = customURLMapping.TokenURL
}
if len(customURLMapping.ProfileURL) > 0 {
profileURL = customURLMapping.ProfileURL
}
}
provider = gitea.NewCustomisedURL(clientID, clientSecret, callbackURL, authURL, tokenURL, profileURL)
case "nextcloud":
authURL := nextcloud.AuthURL
tokenURL := nextcloud.TokenURL
profileURL := nextcloud.ProfileURL
if customURLMapping != nil {
if len(customURLMapping.AuthURL) > 0 {
authURL = customURLMapping.AuthURL
}
if len(customURLMapping.TokenURL) > 0 {
tokenURL = customURLMapping.TokenURL
}
if len(customURLMapping.ProfileURL) > 0 {
profileURL = customURLMapping.ProfileURL
}
}
provider = nextcloud.NewCustomisedURL(clientID, clientSecret, callbackURL, authURL, tokenURL, profileURL)
case "yandex":
// See https://tech.yandex.com/passport/doc/dg/reference/response-docpage/
provider = yandex.New(clientID, clientSecret, callbackURL, "login:email", "login:info", "login:avatar")
case "mastodon":
instanceURL := mastodon.InstanceURL
if customURLMapping != nil && len(customURLMapping.AuthURL) > 0 {
instanceURL = customURLMapping.AuthURL
}
provider = mastodon.NewCustomisedURL(clientID, clientSecret, callbackURL, instanceURL)
}
// always set the name if provider is created so we can support multiple setups of 1 provider
if err == nil && provider != nil {
provider.SetName(providerName)
}
return provider, err
}
// GetDefaultTokenURL return the default token url for the given provider
func GetDefaultTokenURL(provider string) string {
switch provider {
case "github":
return github.TokenURL
case "gitlab":
return gitlab.TokenURL
case "gitea":
return gitea.TokenURL
case "nextcloud":
return nextcloud.TokenURL
}
return ""
}
// GetDefaultAuthURL return the default authorize url for the given provider
func GetDefaultAuthURL(provider string) string {
switch provider {
case "github":
return github.AuthURL
case "gitlab":
return gitlab.AuthURL
case "gitea":
return gitea.AuthURL
case "nextcloud":
return nextcloud.AuthURL
case "mastodon":
return mastodon.InstanceURL
}
return ""
}
// GetDefaultProfileURL return the default profile url for the given provider
func GetDefaultProfileURL(provider string) string {
switch provider {
case "github":
return github.ProfileURL
case "gitlab":
return gitlab.ProfileURL
case "gitea":
return gitea.ProfileURL
case "nextcloud":
return nextcloud.ProfileURL
}
return ""
}
// GetDefaultEmailURL return the default email url for the given provider
func GetDefaultEmailURL(provider string) string {
if provider == "github" {
return github.EmailURL
}
return ""
}