drone/internal/auth/authn/token.go

98 lines
2.3 KiB
Go

// Copyright 2022 Harness Inc. All rights reserved.
// Use of this source code is governed by the Polyform Free Trial License
// that can be found in the LICENSE.md file for this repository.
package authn
import (
"errors"
"fmt"
"net/http"
"strconv"
"strings"
"time"
"github.com/dgrijalva/jwt-go"
"github.com/harness/gitness/internal/store"
"github.com/harness/gitness/internal/token"
"github.com/harness/gitness/types"
"github.com/rs/zerolog/hlog"
)
var _ Authenticator = (*TokenAuthenticator)(nil)
/*
* Authenticates a user by checking for an access token in the
* "Authorization" header or the "access_token" form value.
*/
type TokenAuthenticator struct {
users store.UserStore
}
func NewTokenAuthenticator(userStore store.UserStore) Authenticator {
return &TokenAuthenticator{
users: userStore,
}
}
func (a *TokenAuthenticator) Authenticate(r *http.Request) (*types.User, error) {
ctx := r.Context()
str := extractToken(r)
if len(str) == 0 {
return nil, ErrNoAuthData
}
var user *types.User
parsed, err := jwt.ParseWithClaims(str, &token.Claims{}, func(token_ *jwt.Token) (interface{}, error) {
sub := token_.Claims.(*token.Claims).Subject
id, err := strconv.ParseInt(sub, 10, 64)
if err != nil {
return nil, err
}
user, err = a.users.Find(ctx, id)
if err != nil {
hlog.FromRequest(r).
Error().Err(err).
Int64("user", id).
Msg("cannot find user")
return nil, fmt.Errorf("failed to get user info: %w", err)
}
return []byte(user.Salt), nil
})
if err != nil {
return nil, err
}
if !parsed.Valid {
return nil, errors.New("invalid token")
}
if _, ok := parsed.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, errors.New("invalid token")
}
// this code should be deprecated, since the jwt.ParseWithClaims
// should fail if the token is expired. TODO remove once we have
// proper unit tests in place.
if claims, ok := parsed.Claims.(*token.Claims); ok {
if claims.ExpiresAt > 0 {
if time.Now().Unix() > claims.ExpiresAt {
return nil, errors.New("expired token")
}
}
}
return user, nil
}
func extractToken(r *http.Request) string {
bearer := r.Header.Get("Authorization")
if bearer == "" {
return r.FormValue("access_token")
}
bearer = strings.TrimPrefix(bearer, "Bearer ")
bearer = strings.TrimPrefix(bearer, "IdentityService ")
return bearer
}