zitadel-oidc/pkg/op/verifier_id_token_hint.go
Tim Möhlmann b8e520afd0
fix: allow expired ID token hint to end sessions (#522)
* fix: allow expired ID token hint to end sessions

This change adds a specific error for expired ID Token hints, including too old "issued at" and "max auth age".
The error is returned VerifyIDTokenHint so that the end session handler can choose to ignore this error.

This fixes the behavior to be in line with [OpenID Connect RP-Initiated Logout 1.0, section 4](https://openid.net/specs/openid-connect-rpinitiated-1_0.html#ValidationAndErrorHandling).

* Tes IDTokenHintExpiredError
2024-01-19 11:30:51 +01:00

84 lines
2.2 KiB
Go

package op
import (
"context"
"errors"
"github.com/zitadel/oidc/v3/pkg/oidc"
)
type IDTokenHintVerifier oidc.Verifier
type IDTokenHintVerifierOpt func(*IDTokenHintVerifier)
func WithSupportedIDTokenHintSigningAlgorithms(algs ...string) IDTokenHintVerifierOpt {
return func(verifier *IDTokenHintVerifier) {
verifier.SupportedSignAlgs = algs
}
}
func NewIDTokenHintVerifier(issuer string, keySet oidc.KeySet, opts ...IDTokenHintVerifierOpt) *IDTokenHintVerifier {
verifier := &IDTokenHintVerifier{
Issuer: issuer,
KeySet: keySet,
}
for _, opt := range opts {
opt(verifier)
}
return verifier
}
type IDTokenHintExpiredError struct {
error
}
func (e IDTokenHintExpiredError) Unwrap() error {
return e.error
}
func (e IDTokenHintExpiredError) Is(err error) bool {
return errors.Is(err, e.error)
}
// VerifyIDTokenHint validates the id token according to
// https://openid.net/specs/openid-connect-core-1_0.html#IDTokenValidation.
// In case of an expired token both the Claims and first encountered expiry related error
// is returned of type [IDTokenHintExpiredError]. In that case the caller can choose to still
// trust the token for cases like logout, as signature and other verifications succeeded.
func VerifyIDTokenHint[C oidc.Claims](ctx context.Context, token string, v *IDTokenHintVerifier) (claims C, err error) {
var nilClaims C
decrypted, err := oidc.DecryptToken(token)
if err != nil {
return nilClaims, err
}
payload, err := oidc.ParseToken(decrypted, &claims)
if err != nil {
return nilClaims, err
}
if err := oidc.CheckIssuer(claims, v.Issuer); err != nil {
return nilClaims, err
}
if err = oidc.CheckSignature(ctx, decrypted, payload, claims, v.SupportedSignAlgs, v.KeySet); err != nil {
return nilClaims, err
}
if err = oidc.CheckAuthorizationContextClassReference(claims, v.ACR); err != nil {
return nilClaims, err
}
if err = oidc.CheckExpiration(claims, v.Offset); err != nil {
return claims, IDTokenHintExpiredError{err}
}
if err = oidc.CheckIssuedAt(claims, v.MaxAgeIAT, v.Offset); err != nil {
return claims, IDTokenHintExpiredError{err}
}
if err = oidc.CheckAuthTime(claims, v.MaxAge); err != nil {
return claims, IDTokenHintExpiredError{err}
}
return claims, nil
}