package auth import ( "net/http" "os" "time" "codeberg.org/u1f320/pronouns.cc/backend/db" "codeberg.org/u1f320/pronouns.cc/backend/log" "codeberg.org/u1f320/pronouns.cc/backend/server" "emperror.dev/errors" "github.com/go-chi/render" "github.com/mediocregopher/radix/v4" "github.com/rs/xid" "golang.org/x/oauth2" "google.golang.org/api/idtoken" ) var googleOAuthConfig = oauth2.Config{ ClientID: os.Getenv("GOOGLE_CLIENT_ID"), ClientSecret: os.Getenv("GOOGLE_CLIENT_SECRET"), Endpoint: oauth2.Endpoint{ AuthURL: "https://accounts.google.com/o/oauth2/auth", TokenURL: "https://oauth2.googleapis.com/token", AuthStyle: oauth2.AuthStyleInParams, }, Scopes: []string{"openid", "https://www.googleapis.com/auth/userinfo.email"}, } type googleCallbackResponse struct { HasAccount bool `json:"has_account"` // if true, Token and User will be set. if false, Ticket and Google will be set Token string `json:"token,omitempty"` User *userResponse `json:"user,omitempty"` Google string `json:"google,omitempty"` // username, for UI purposes Ticket string `json:"ticket,omitempty"` RequireInvite bool `json:"require_invite"` // require an invite for signing up IsDeleted bool `json:"is_deleted"` DeletedAt *time.Time `json:"deleted_at,omitempty"` SelfDelete *bool `json:"self_delete,omitempty"` DeleteReason *string `json:"delete_reason,omitempty"` } type partialGoogleUser struct { ID string `json:"id"` Email string `json:"email"` } func (s *Server) googleCallback(w http.ResponseWriter, r *http.Request) error { ctx := r.Context() decoded, err := Decode[oauthCallbackRequest](r) if err != nil { return server.APIError{Code: server.ErrBadRequest} } // if the state can't be validated, return if valid, err := s.validateCSRFState(ctx, decoded.State); !valid { if err != nil { return err } return server.APIError{Code: server.ErrInvalidState} } cfg := googleOAuthConfig cfg.RedirectURL = decoded.CallbackDomain + "/auth/login/google" token, err := cfg.Exchange(r.Context(), decoded.Code) if err != nil { log.Errorf("exchanging oauth code: %v", err) return server.APIError{Code: server.ErrInvalidOAuthCode} } rawToken := token.Extra("id_token") if rawToken == nil { log.Debug("id_token was nil") return server.APIError{Code: server.ErrInternalServerError} } idToken, ok := rawToken.(string) if !ok { log.Debug("id_token was not a string") return server.APIError{Code: server.ErrInternalServerError} } payload, err := idtoken.Validate(ctx, idToken, "") if err != nil { log.Errorf("getting id token payload: %v", err) return server.APIError{Code: server.ErrInternalServerError} } googleID, ok := payload.Claims["sub"].(string) if !ok { log.Debug("id_token.claims.sub was not a string") return server.APIError{Code: server.ErrInternalServerError} } googleUsername, ok := payload.Claims["email"].(string) if !ok { log.Debug("id_token.claims.email was not a string") return server.APIError{Code: server.ErrInternalServerError} } u, err := s.DB.GoogleUser(ctx, googleID) if err == nil { if u.DeletedAt != nil { // store cancel delete token token := undeleteToken() err = s.saveUndeleteToken(ctx, u.ID, token) if err != nil { log.Errorf("saving undelete token: %v", err) return err } render.JSON(w, r, googleCallbackResponse{ HasAccount: true, Token: token, User: dbUserToUserResponse(u, []db.Field{}), IsDeleted: true, DeletedAt: u.DeletedAt, SelfDelete: u.SelfDelete, DeleteReason: u.DeleteReason, }) return nil } err = u.UpdateFromGoogle(ctx, s.DB, googleID, googleUsername) if err != nil { log.Errorf("updating user %v with Google info: %v", u.ID, err) } // TODO: implement user + token permissions tokenID := xid.New() token, err := s.Auth.CreateToken(u.ID, tokenID, u.IsAdmin, false, true) if err != nil { return err } // save token to database _, err = s.DB.SaveToken(ctx, u.ID, tokenID, false, false) if err != nil { return errors.Wrap(err, "saving token to database") } fields, err := s.DB.UserFields(ctx, u.ID) if err != nil { return errors.Wrap(err, "querying fields") } render.JSON(w, r, googleCallbackResponse{ HasAccount: true, Token: token, User: dbUserToUserResponse(u, fields), }) return nil } else if err != db.ErrUserNotFound { // internal error return err } // no user found, so save a ticket + save their Google info in Redis ticket := RandBase64(32) err = s.DB.SetJSON(ctx, "google:"+ticket, partialGoogleUser{ID: googleID, Email: googleUsername}, "EX", "600") if err != nil { log.Errorf("setting Google user for ticket %q: %v", ticket, err) return err } render.JSON(w, r, googleCallbackResponse{ HasAccount: false, Google: googleUsername, Ticket: ticket, RequireInvite: s.RequireInvite, }) return nil } func (s *Server) googleLink(w http.ResponseWriter, r *http.Request) error { ctx := r.Context() claims, _ := server.ClaimsFromContext(ctx) // only site tokens can be used for this endpoint if claims.APIToken { return server.APIError{Code: server.ErrMissingPermissions, Details: "This endpoint cannot be used by API tokens"} } req, err := Decode[linkRequest](r) if err != nil { return server.APIError{Code: server.ErrBadRequest} } u, err := s.DB.User(ctx, claims.UserID) if err != nil { return errors.Wrap(err, "getting user") } if u.Google != nil { return server.APIError{Code: server.ErrAlreadyLinked} } gu := new(partialGoogleUser) err = s.DB.GetJSON(ctx, "google:"+req.Ticket, &gu) if err != nil { log.Errorf("getting google user for ticket: %v", err) return server.APIError{Code: server.ErrInvalidTicket} } if gu.ID == "" { log.Errorf("linking user with id %v: user ID was empty", claims.UserID) return server.APIError{Code: server.ErrInternalServerError, Details: "Google user ID is empty"} } err = u.UpdateFromGoogle(ctx, s.DB, gu.ID, gu.Email) if err != nil { return errors.Wrap(err, "updating user from google") } fields, err := s.DB.UserFields(ctx, u.ID) if err != nil { return errors.Wrap(err, "getting user fields") } render.JSON(w, r, dbUserToUserResponse(u, fields)) return nil } func (s *Server) googleUnlink(w http.ResponseWriter, r *http.Request) error { ctx := r.Context() claims, _ := server.ClaimsFromContext(ctx) // only site tokens can be used for this endpoint if claims.APIToken { return server.APIError{Code: server.ErrMissingPermissions, Details: "This endpoint cannot be used by API tokens"} } u, err := s.DB.User(ctx, claims.UserID) if err != nil { return errors.Wrap(err, "getting user") } if u.Google == nil { return server.APIError{Code: server.ErrNotLinked} } // cannot unlink last auth provider if u.NumProviders() <= 1 { return server.APIError{Code: server.ErrLastProvider} } err = u.UnlinkGoogle(ctx, s.DB) if err != nil { return errors.Wrap(err, "updating user in db") } fields, err := s.DB.UserFields(ctx, u.ID) if err != nil { return errors.Wrap(err, "getting user fields") } render.JSON(w, r, dbUserToUserResponse(u, fields)) return nil } func (s *Server) googleSignup(w http.ResponseWriter, r *http.Request) error { ctx := r.Context() req, err := Decode[signupRequest](r) if err != nil { return server.APIError{Code: server.ErrBadRequest} } if s.RequireInvite && req.InviteCode == "" { return server.APIError{Code: server.ErrInviteRequired} } valid, taken, err := s.DB.UsernameTaken(ctx, req.Username) if err != nil { return err } if !valid { return server.APIError{Code: server.ErrInvalidUsername} } if taken { return server.APIError{Code: server.ErrUsernameTaken} } tx, err := s.DB.Begin(ctx) if err != nil { return errors.Wrap(err, "beginning transaction") } defer tx.Rollback(ctx) gu := new(partialGoogleUser) err = s.DB.GetJSON(ctx, "google:"+req.Ticket, &gu) if err != nil { log.Errorf("getting google user for ticket: %v", err) return server.APIError{Code: server.ErrInvalidTicket} } u, err := s.DB.CreateUser(ctx, tx, req.Username) if err != nil { if errors.Cause(err) == db.ErrUsernameTaken { return server.APIError{Code: server.ErrUsernameTaken} } return errors.Wrap(err, "creating user") } if gu.ID == "" { log.Errorf("creating user with name %q: user ID was empty", req.Username) return server.APIError{Code: server.ErrInternalServerError, Details: "Google user ID is empty"} } err = u.UpdateFromGoogle(ctx, tx, gu.ID, gu.Email) if err != nil { return errors.Wrap(err, "updating user from google") } if s.RequireInvite { valid, used, err := s.DB.InvalidateInvite(ctx, tx, req.InviteCode) if err != nil { return errors.Wrap(err, "checking and invalidating invite") } if !valid { return server.APIError{Code: server.ErrInviteRequired} } if used { return server.APIError{Code: server.ErrInviteAlreadyUsed} } } // delete sign up ticket err = s.DB.Redis.Do(ctx, radix.Cmd(nil, "DEL", "google:"+req.Ticket)) if err != nil { return errors.Wrap(err, "deleting signup ticket") } // commit transaction err = tx.Commit(ctx) if err != nil { return errors.Wrap(err, "committing transaction") } // create token // TODO: implement user + token permissions tokenID := xid.New() token, err := s.Auth.CreateToken(u.ID, tokenID, false, false, true) if err != nil { return errors.Wrap(err, "creating token") } // save token to database _, err = s.DB.SaveToken(ctx, u.ID, tokenID, false, false) if err != nil { return errors.Wrap(err, "saving token to database") } // return user render.JSON(w, r, signupResponse{ User: *dbUserToUserResponse(u, nil), Token: token, }) return nil }