PublicKeyCredential: authenticatorAttachment property

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The authenticatorAttachment read-only property of the PublicKeyCredential interface is a string that indicates the general category of authenticator used during the associated navigator.credentials.create() or navigator.credentials.get() call.

Value

A string, which will be one of the following values:

"platform"

The authenticator is part of the device WebAuthn is running on (termed a platform authenticator), therefore WebAuthn will communicate with it using a transport available to that platform, such as a platform-specific API. A public key credential bound to a platform authenticator is called a platform credential.

"cross-platform"

The authenticator is not a part of the device WebAuthn is running on (termed a roaming authenticator as it can roam between different devices), therefore WebAuthn will communicate with it using a cross-platform transport protocol such as Bluetooth or NFC. A public key credential bound to a roaming authenticator is called a roaming credential.

Examples

js

const options = {
  challenge: new Uint8Array(26) /* from the server */,
  rp: {
    name: "Example CORP",
    id: "login.example.com",
  },
  user: {
    id: new Uint8Array(26) /* To be changed for each user */,
    name: "canand@example.com",
    displayName: "Carina Anand",
  },
  pubKeyCredParams: [
    {
      type: "public-key",
      alg: -7,
    },
  ],
};

navigator.credentials
  .create({ publicKey: options })
  .then((pubKeyCredential) => {
    const attachment = pubKeyCredential.authenticatorAttachment;
    // Do something with authenticatorAttachment
  })
  .catch((err) => {
    // Deal with any error
  });

Specifications

Specification
Web Authentication: An API for accessing Public Key Credentials - Level 3
# dom-publickeycredential-authenticatorattachment

Browser compatibility

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