feat: add token IDs, store tokens in db for early invalidation

backend/db/tokens.go

@@ -0,0 +1,98 @@
+package db
+
+import (
+	"context"
+	"time"
+
+	"emperror.dev/errors"
+	"github.com/georgysavva/scany/pgxscan"
+	"github.com/jackc/pgx/v4"
+	"github.com/rs/xid"
+)
+
+type Token struct {
+	UserID      xid.ID
+	TokenID     xid.ID
+	Invalidated bool
+	Created     time.Time
+	Expires     time.Time
+}
+
+func (db *DB) TokenValid(ctx context.Context, userID, tokenID xid.ID) (valid bool, err error) {
+	sql, args, err := sq.Select("*").From("tokens").
+		Where("user_id = ?", userID).
+		Where("token_id = ?", tokenID).
+		ToSql()
+	if err != nil {
+		return false, errors.Wrap(err, "building sql")
+	}
+
+	var t Token
+	err = pgxscan.Get(ctx, db, &t, sql, args...)
+	if err != nil {
+		if errors.Cause(err) == pgx.ErrNoRows {
+			return false, nil
+		}
+
+		return false, errors.Wrap(err, "getting from database")
+	}
+
+	now := time.Now()
+	return !t.Invalidated && t.Created.Before(now) && t.Expires.After(now), nil
+}
+
+func (db *DB) Tokens(ctx context.Context, userID xid.ID) (ts []Token, err error) {
+	sql, args, err := sq.Select("*").From("tokens").
+		Where("user_id = ?", userID).
+		Where("expires > ?", time.Now()).
+		OrderBy("created").
+		ToSql()
+	if err != nil {
+		return nil, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Select(ctx, db, &ts, sql, args...)
+	if err != nil {
+		return nil, errors.Wrap(err, "getting from database")
+	}
+	return ts, nil
+}
+
+// 3 months, might be customizable later
+const ExpiryTime = 3 * 30 * 24 * time.Hour
+
+// SaveToken saves a token to the database.
+func (db *DB) SaveToken(ctx context.Context, userID xid.ID, tokenID xid.ID) (t Token, err error) {
+	sql, args, err := sq.Insert("tokens").
+		Columns("user_id", "token_id", "expires").
+		Values(userID, tokenID, time.Now().Add(ExpiryTime)).
+		Suffix("RETURNING *").
+		ToSql()
+	if err != nil {
+		return t, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Get(ctx, db, &t, sql, args...)
+	if err != nil {
+		return t, errors.Wrap(err, "inserting token")
+	}
+	return t, nil
+}
+
+func (db *DB) InvalidateToken(ctx context.Context, userID xid.ID, tokenID xid.ID) (t Token, err error) {
+	sql, args, err := sq.Update("tokens").
+		Where("user_id = ?").
+		Where("token_id = ?").
+		Set("invalidated", true).
+		Suffix("RETURNING *").
+		ToSql()
+	if err != nil {
+		return t, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Get(ctx, db, &t, sql, args...)
+	if err != nil {
+		return t, errors.Wrap(err, "invalidating token")
+	}
+	return t, nil
+}

backend/routes/auth/discord.go

@@ -11,6 +11,7 @@ import (
 	"github.com/bwmarrin/discordgo"
 	"github.com/go-chi/render"
 	"github.com/mediocregopher/radix/v4"
+	"github.com/rs/xid"
 	"golang.org/x/oauth2"
 )
 
@@ -81,11 +82,19 @@ func (s *Server) discordCallback(w http.ResponseWriter, r *http.Request) error {
 			log.Errorf("updating user %v with Discord info: %v", u.ID, err)
 		}
 
-		token, err := s.Auth.CreateToken(u.ID)
+		// TODO: implement user + token permissions
+		tokenID := xid.New()
+		token, err := s.Auth.CreateToken(u.ID, tokenID, false, true)
 		if err != nil {
 			return err
 		}
 
+		// save token to database
+		_, err = s.DB.SaveToken(ctx, u.ID, tokenID)
+		if err != nil {
+			return errors.Wrap(err, "saving token to database")
+		}
+
 		render.JSON(w, r, discordCallbackResponse{
 			HasAccount: true,
 			Token:      token,
@@ -206,11 +215,19 @@ func (s *Server) discordSignup(w http.ResponseWriter, r *http.Request) error {
 	}
 
 	// create token
-	token, err := s.Auth.CreateToken(u.ID)
+	// TODO: implement user + token permissions
+	tokenID := xid.New()
+	token, err := s.Auth.CreateToken(u.ID, tokenID, false, true)
 	if err != nil {
 		return errors.Wrap(err, "creating token")
 	}
 
+	// save token to database
+	_, err = s.DB.SaveToken(ctx, u.ID, tokenID)
+	if err != nil {
+		return errors.Wrap(err, "saving token to database")
+	}
+
 	// return user
 	render.JSON(w, r, signupResponse{
 		User:  *dbUserToUserResponse(u),

backend/routes/auth/routes.go

@@ -67,6 +67,11 @@ func Mount(srv *server.Server, r chi.Router) {
 		// invite routes
 		r.With(server.MustAuth).Get("/invites", server.WrapHandler(s.getInvites))
 		r.With(server.MustAuth).Post("/invites", server.WrapHandler(s.createInvite))
+
+		// tokens
+		r.With(server.MustAuth).Get("/tokens", server.WrapHandler(s.getTokens))
+		r.With(server.MustAuth).Post("/tokens", server.WrapHandler(s.createToken))
+		r.With(server.MustAuth).Delete("/tokens", server.WrapHandler(s.deleteToken))
 	})
 }
 

backend/routes/auth/tokens.go

@@ -0,0 +1,72 @@
+package auth
+
+import (
+	"net/http"
+	"time"
+
+	"codeberg.org/u1f320/pronouns.cc/backend/db"
+	"codeberg.org/u1f320/pronouns.cc/backend/server"
+	"emperror.dev/errors"
+	"github.com/go-chi/render"
+	"github.com/rs/xid"
+)
+
+type getTokenResponse struct {
+	TokenID xid.ID    `json:"id"`
+	Created time.Time `json:"created"`
+	Expires time.Time `json:"expires"`
+}
+
+func dbTokenToGetResponse(t db.Token) getTokenResponse {
+	return getTokenResponse{
+		TokenID: t.TokenID,
+		Created: t.Created,
+		Expires: t.Expires,
+	}
+}
+
+func (s *Server) getTokens(w http.ResponseWriter, r *http.Request) error {
+	ctx := r.Context()
+	claims, _ := server.ClaimsFromContext(ctx)
+
+	tokens, err := s.DB.Tokens(ctx, claims.UserID)
+	if err != nil {
+		return errors.Wrap(err, "getting tokens")
+	}
+
+	resps := make([]getTokenResponse, len(tokens))
+	for i := range tokens {
+		resps[i] = dbTokenToGetResponse(tokens[i])
+	}
+
+	render.JSON(w, r, resps)
+	return nil
+}
+
+type deleteTokenResponse struct {
+	TokenID     xid.ID    `json:"id"`
+	Invalidated bool      `json:"invalidated"`
+	Created     time.Time `json:"time"`
+}
+
+func (s *Server) deleteToken(w http.ResponseWriter, r *http.Request) error {
+	ctx := r.Context()
+	claims, _ := server.ClaimsFromContext(ctx)
+
+	t, err := s.DB.InvalidateToken(ctx, claims.UserID, claims.TokenID)
+	if err != nil {
+		return errors.Wrap(err, "invalidating token")
+	}
+
+	render.JSON(w, r, deleteTokenResponse{
+		TokenID:     t.TokenID,
+		Invalidated: t.Invalidated,
+		Created:     t.Created,
+	})
+	return nil
+}
+
+func (s *Server) createToken(w http.ResponseWriter, r *http.Request) error {
+	// unimplemented right now
+	return server.APIError{Code: server.ErrForbidden}
+}

backend/server/auth.go

@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"strings"
 
+	"codeberg.org/u1f320/pronouns.cc/backend/log"
 	"codeberg.org/u1f320/pronouns.cc/backend/server/auth"
 	"github.com/go-chi/render"
 )
@@ -28,6 +29,27 @@ func (s *Server) maybeAuth(next http.Handler) http.Handler {
 			return
 		}
 
+		// "valid" here refers to existence and expiry date, not whether the token is known
+		valid, err := s.DB.TokenValid(r.Context(), claims.UserID, claims.TokenID)
+		if err != nil {
+			log.Errorf("validating token for user %v: %v", claims.UserID, err)
+			render.Status(r, errCodeStatuses[ErrInternalServerError])
+			render.JSON(w, r, APIError{
+				Code:    ErrInternalServerError,
+				Message: errCodeMessages[ErrInternalServerError],
+			})
+			return
+		}
+
+		if !valid {
+			render.Status(r, errCodeStatuses[ErrInvalidToken])
+			render.JSON(w, r, APIError{
+				Code:    ErrInvalidToken,
+				Message: errCodeMessages[ErrInvalidToken],
+			})
+			return
+		}
+
 		ctx := context.WithValue(r.Context(), ctxKeyClaims, claims)
 
 		next.ServeHTTP(w, r.WithContext(ctx))

backend/server/auth/auth.go

@@ -15,6 +15,12 @@ import (
 // Claims are the claims used in a token.
 type Claims struct {
 	UserID      xid.ID `json:"sub"`
+	TokenID     xid.ID `json:"jti"`
+	UserIsAdmin bool   `json:"adm"`
+
+	// TokenWrite specifies whether this token can be used for write actions.
+	// If set to false, this token can only be used for read actions.
+	TokenWrite bool `json:"twr"`
 
 	jwt.RegisteredClaims
 }
@@ -37,16 +43,20 @@ func New() *Verifier {
 	return &Verifier{key: key}
 }
 
-const expireDays = 30
+// ExpireDays is after how many days the token will expire.
+const ExpireDays = 30
 
 // CreateToken creates a token for the given user ID.
 // It expires after 30 days.
-func (v *Verifier) CreateToken(userID xid.ID) (string, error) {
+func (v *Verifier) CreateToken(userID, tokenID xid.ID, isAdmin bool, isWriteToken bool) (token string, err error) {
 	now := time.Now()
-	expires := now.Add(expireDays * 24 * time.Hour)
+	expires := now.Add(ExpireDays * 24 * time.Hour)
 
-	token := jwt.NewWithClaims(jwt.SigningMethodHS256, Claims{
+	t := jwt.NewWithClaims(jwt.SigningMethodHS256, Claims{
 		UserID:      userID,
+		TokenID:     tokenID,
+		UserIsAdmin: isAdmin,
+		TokenWrite:  isWriteToken,
 		RegisteredClaims: jwt.RegisteredClaims{
 			Issuer:    "pronouns",
 			ExpiresAt: jwt.NewNumericDate(expires),
@@ -55,7 +65,7 @@ func (v *Verifier) CreateToken(userID xid.ID) (string, error) {
 		},
 	})
 
-	return token.SignedString(v.key)
+	return t.SignedString(v.key)
 }
 
 // Claims parses the given token and returns its Claims.

scripts/migrate/003_add_tokens.sql

@@ -0,0 +1,15 @@
+-- +migrate Up
+
+-- 2022-12-23: Add database-backed tokens
+create table tokens (
+    user_id     text not null references users (id) on delete cascade,
+    token_id    text primary key,
+    invalidated boolean not null default false,
+    created     timestamptz not null default now(),
+    expires     timestamptz not null
+);
+
+-- Unrelatedly, this migration also changes the column type for invites.created to timestamptz (from plain timestamp)
+-- This does not change anything code-wise, but it's recommended over plain timestamp because plain timestamp does not handle timezones correctly
+alter table invites alter column created type timestamptz;
+alter table invites alter column created set default now();