gotosocial/internal/oauth/oauth.go
2021-03-18 23:27:43 +01:00

342 lines
11 KiB
Go

/*
GoToSocial
Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package oauth
import (
"net/http"
"net/url"
"github.com/gin-contrib/sessions"
"github.com/gin-gonic/gin"
"github.com/go-pg/pg/v10"
"github.com/gotosocial/gotosocial/internal/api"
"github.com/gotosocial/gotosocial/internal/gtsmodel"
"github.com/gotosocial/gotosocial/pkg/mastotypes"
"github.com/gotosocial/oauth2/v4"
"github.com/gotosocial/oauth2/v4/errors"
"github.com/gotosocial/oauth2/v4/manage"
"github.com/gotosocial/oauth2/v4/server"
"github.com/sirupsen/logrus"
"golang.org/x/crypto/bcrypt"
)
const methodAny = "ANY"
type API struct {
manager *manage.Manager
server *server.Server
conn *pg.DB
log *logrus.Logger
}
type login struct {
Email string `form:"username"`
Password string `form:"password"`
}
type code struct {
Code string `form:"code"`
}
func New(ts oauth2.TokenStore, cs oauth2.ClientStore, conn *pg.DB, log *logrus.Logger) *API {
manager := manage.NewDefaultManager()
manager.MapTokenStorage(ts)
manager.MapClientStorage(cs)
manager.SetAuthorizeCodeTokenCfg(manage.DefaultAuthorizeCodeTokenCfg)
sc := &server.Config{
TokenType: "Bearer",
// Must follow the spec.
AllowGetAccessRequest: false,
// Support only the non-implicit flow.
AllowedResponseTypes: []oauth2.ResponseType{oauth2.Code},
// Allow:
// - Authorization Code (for first & third parties)
// - Refreshing Tokens
//
// Deny:
// - Resource owner secrets (password grant)
// - Client secrets
AllowedGrantTypes: []oauth2.GrantType{
oauth2.AuthorizationCode,
oauth2.Refreshing,
},
AllowedCodeChallengeMethods: []oauth2.CodeChallengeMethod{
oauth2.CodeChallengePlain,
},
}
srv := server.NewServer(sc, manager)
srv.SetInternalErrorHandler(func(err error) *errors.Response {
log.Errorf("internal oauth error: %s", err)
return nil
})
srv.SetResponseErrorHandler(func(re *errors.Response) {
log.Errorf("internal response error: %s", re.Error)
})
api := &API{
manager: manager,
server: srv,
conn: conn,
log: log,
}
api.server.SetUserAuthorizationHandler(api.UserAuthorizationHandler)
api.server.SetClientInfoHandler(server.ClientFormHandler)
return api
}
func (a *API) AddRoutes(s api.Server) error {
s.AttachHandler(http.MethodGet, "/auth/sign_in", a.SignInGETHandler)
s.AttachHandler(http.MethodPost, "/auth/sign_in", a.SignInPOSTHandler)
s.AttachHandler(http.MethodPost, "/oauth/token", a.TokenHandler)
s.AttachHandler(http.MethodGet, "/oauth/authorize", a.AuthorizeGETHandler)
s.AttachHandler(http.MethodPost, "/oauth/authorize", a.AuthorizePOSTHandler)
// s.AttachHandler(http.MethodGet, "/auth", a.AuthGETHandler)
return nil
}
func incorrectPassword() (string, error) {
return "", errors.New("password/email combination was incorrect")
}
/*
MAIN HANDLERS -- serve these through a server/router
*/
// SignInGETHandler should be served at https://example.org/auth/sign_in.
// The idea is to present a sign in page to the user, where they can enter their username and password.
// The form will then POST to the sign in page, which will be handled by SignInPOSTHandler
func (a *API) SignInGETHandler(c *gin.Context) {
a.log.WithField("func", "SignInGETHandler").Trace("serving sign in html")
c.HTML(http.StatusOK, "sign-in.tmpl", gin.H{})
}
// SignInPOSTHandler should be served at https://example.org/auth/sign_in.
// The idea is to present a sign in page to the user, where they can enter their username and password.
// The handler will then redirect to the auth handler served at /auth
func (a *API) SignInPOSTHandler(c *gin.Context) {
l := a.log.WithField("func", "SignInPOSTHandler")
s := sessions.Default(c)
form := &login{}
if err := c.ShouldBind(form); err != nil {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
return
}
l.Tracef("parsed form: %+v", form)
userid, err := a.ValidatePassword(form.Email, form.Password)
if err != nil {
c.String(http.StatusForbidden, err.Error())
return
}
s.Set("username", userid)
if err := s.Save(); err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
return
}
l.Trace("redirecting to auth page")
c.Redirect(http.StatusFound, "/oauth/authorize")
}
// TokenHandler should be served as a POST at https://example.org/oauth/token
// The idea here is to serve an oauth access token to a user, which can be used for authorizing against non-public APIs.
// See https://docs.joinmastodon.org/methods/apps/oauth/#obtain-a-token
func (a *API) TokenHandler(c *gin.Context) {
l := a.log.WithField("func", "TokenHandler")
l.Trace("entered token handler, will now go to server.HandleTokenRequest")
if err := a.server.HandleTokenRequest(c.Writer, c.Request); err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
}
}
// AuthorizeGETHandler should be served as GET at https://example.org/oauth/authorize
// The idea here is to present an oauth authorize page to the user, with a button
// that they have to click to accept. See here: https://docs.joinmastodon.org/methods/apps/oauth/#authorize-a-user
func (a *API) AuthorizeGETHandler(c *gin.Context) {
l := a.log.WithField("func", "AuthorizeGETHandler")
s := sessions.Default(c)
v := s.Get("username")
if username, ok := v.(string); !ok || username == "" {
l.Trace("username was empty, parsing form then redirecting to sign in page")
form := &mastotypes.OAuthAuthorize{}
if err := c.ShouldBind(form); err != nil {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
return
}
l.Tracef("parsed form: %+v", form)
if form.ResponseType == "" || form.ClientID == "" || form.RedirectURI == "" {
c.JSON(http.StatusBadRequest, gin.H{"error": "missing one of: response_type, client_id or redirect_uri"})
return
}
// save these values from the form so we can use them elsewhere in the session
s.Set("force_login", form.ForceLogin)
s.Set("response_type", form.ResponseType)
s.Set("client_id", form.ClientID)
s.Set("redirect_uri", form.RedirectURI)
s.Set("scope", form.Scope)
if err := s.Save(); err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
return
}
c.Redirect(http.StatusFound, "/auth/sign_in")
return
}
l.Trace("serving authorize html")
c.HTML(http.StatusOK, "authorize.tmpl", gin.H{})
}
// AuthorizePOSTHandler should be served as POST at https://example.org/oauth/authorize
// The idea here is to present an oauth authorize page to the user, with a button
// that they have to click to accept. See here: https://docs.joinmastodon.org/methods/apps/oauth/#authorize-a-user
func (a *API) AuthorizePOSTHandler(c *gin.Context) {
l := a.log.WithField("func", "AuthorizePOSTHandler")
s := sessions.Default(c)
v := s.Get("username")
if username, ok := v.(string); !ok || username == "" {
c.JSON(http.StatusUnauthorized, gin.H{"error": "you are not signed in"})
}
values := url.Values{}
if v, ok := s.Get("force_login").(string); !ok {
c.JSON(http.StatusBadRequest, gin.H{"error": "session missing force_login"})
return
} else {
values.Add("force_login", v)
}
if v, ok := s.Get("response_type").(string); !ok {
c.JSON(http.StatusBadRequest, gin.H{"error": "session missing response_type"})
return
} else {
values.Add("response_type", v)
}
if v, ok := s.Get("client_id").(string); !ok {
c.JSON(http.StatusBadRequest, gin.H{"error": "session missing client_id"})
return
} else {
values.Add("client_id", v)
}
if v, ok := s.Get("redirect_uri").(string); !ok {
c.JSON(http.StatusBadRequest, gin.H{"error": "session missing redirect_uri"})
return
} else {
values.Add("redirect_uri", v)
}
if v, ok := s.Get("scope").(string); !ok {
c.JSON(http.StatusBadRequest, gin.H{"error": "session missing scope"})
return
} else {
values.Add("scope", v)
}
if v, ok := s.Get("username").(string); !ok {
c.JSON(http.StatusBadRequest, gin.H{"error": "session missing username"})
return
} else {
values.Add("username", v)
}
c.Request.Form = values
l.Tracef("values on request set to %+v", c.Request.Form)
if err := s.Save(); err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
return
}
if err := a.server.HandleAuthorizeRequest(c.Writer, c.Request); err != nil {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
}
}
/*
SUB-HANDLERS -- don't serve these directly, they should be attached to the oauth2 server
*/
// PasswordAuthorizationHandler takes a username (in this case, we use an email address)
// and a password. The goal is to authenticate the password against the one for that email
// address stored in the database. If OK, we return the userid (a uuid) for that user,
// so that it can be used in further Oauth flows to generate a token/retreieve an oauth client from the db.
func (a *API) ValidatePassword(email string, password string) (userid string, err error) {
l := a.log.WithField("func", "PasswordAuthorizationHandler")
// make sure an email/password was provided and bail if not
if email == "" || password == "" {
l.Debug("email or password was not provided")
return incorrectPassword()
}
// first we select the user from the database based on email address, bail if no user found for that email
gtsUser := &gtsmodel.User{}
if err := a.conn.Model(gtsUser).Where("email = ?", email).Select(); err != nil {
l.Debugf("user %s was not retrievable from db during oauth authorization attempt: %s", email, err)
return incorrectPassword()
}
// make sure a password is actually set and bail if not
if gtsUser.EncryptedPassword == "" {
l.Warnf("encrypted password for user %s was empty for some reason", gtsUser.Email)
return incorrectPassword()
}
// compare the provided password with the encrypted one from the db, bail if they don't match
if err := bcrypt.CompareHashAndPassword([]byte(gtsUser.EncryptedPassword), []byte(password)); err != nil {
l.Debugf("password hash didn't match for user %s during login attempt: %s", gtsUser.Email, err)
return incorrectPassword()
}
// If we've made it this far the email/password is correct, so we can just return the id of the user.
userid = gtsUser.ID
l.Tracef("returning (%s, %s)", userid, err)
return
}
// UserAuthorizationHandler gets the user's email address from the form key 'username'
// or redirects to the /auth/sign_in page, if this key is not present.
func (a *API) UserAuthorizationHandler(w http.ResponseWriter, r *http.Request) (username string, err error) {
l := a.log.WithField("func", "UserAuthorizationHandler")
username = r.FormValue("username")
if username == "" {
l.Trace("username was empty, redirecting to sign in page")
http.Redirect(w, r, "/auth/sign_in", http.StatusFound)
return "", nil
}
l.Tracef("returning (%s, %s)", username, err)
return username, err
}