AuthenticatorAssertionResponse

{{APIRef("Web Authentication API")}}{{securecontext_header}}

The AuthenticatorAssertionResponse interface of the Web Authentication API contains a digital signature from the private key of a particular WebAuthn credential. The relying party's server can verify this signature to authenticate a user, for example when they sign in.

An AuthenticatorAssertionResponse object instance is available in the {{domxref("PublicKeyCredential.response", "response")}} property of a {{domxref("PublicKeyCredential")}} object returned by a successful {{domxref("CredentialsContainer.get()", "navigator.credentials.get()")}} call.

This interface inherits from {{domxref("AuthenticatorResponse")}}.

{{InheritanceDiagram}}

[!NOTE] This interface is restricted to top-level contexts. Use from within an {{HTMLElement("iframe")}} element will not have any effect.

Instance properties

Also inherits properties from its parent, {{domxref("AuthenticatorResponse")}}.

• {{domxref("AuthenticatorAssertionResponse.authenticatorData")}} {{ReadOnlyInline}}
  • : An {{jsxref("ArrayBuffer")}} containing information from the authenticator such as the Relying Party ID Hash (rpIdHash), a signature counter, test of user presence and user verification flags, and any extensions processed by the authenticator.
• {{domxref("AuthenticatorResponse.clientDataJSON")}} {{ReadOnlyInline}}
  • : Contains the JSON-compatible serialization of the data passed from the browser to the authenticator in order to authenticate with this credential — i.e., when {{domxref("CredentialsContainer.get()")}} is called with a publicKey option. This data contains some information from the options passed into the get() call, and some information controlled by the browser.
• {{domxref("AuthenticatorAssertionResponse.signature")}} {{ReadOnlyInline}}
  • : An assertion signature over {{domxref("AuthenticatorAssertionResponse.authenticatorData")}} and {{domxref("AuthenticatorResponse.clientDataJSON")}}. The assertion signature is created with the private key of the key pair that was created during the originating {{domxref("CredentialsContainer.create()","navigator.credentials.create()")}} call and verified using the public key of that same key pair.
• {{domxref("AuthenticatorAssertionResponse.userHandle")}} {{ReadOnlyInline}}
  • : An {{jsxref("ArrayBuffer")}} containing an opaque user identifier, specified as user.id in the options passed to the originating {{domxref("CredentialsContainer.create()","navigator.credentials.create()")}} call.

Instance methods

None.

Examples

See Retrieving a public key credential for a detailed example.

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{domxref("AuthenticatorAttestationResponse")}}: the interface for the type of response given when creating a new credential
• {{domxref("AuthenticatorResponse")}}: the parent interface