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<pre class='metadata'>
Title: Web Authentication: An API for accessing Public Key Credentials
Status: ED
Prepare for TR: true
TR: https://www.w3.org/TR/webauthn/
ED: https://w3c.github.io/webauthn/
Previous Version: https://www.w3.org/TR/2017/WD-webauthn-20170505/
Previous Version: https://www.w3.org/TR/2017/WD-webauthn-20170216/
Previous Version: https://www.w3.org/TR/2016/WD-webauthn-20161207/
Previous Version: https://www.w3.org/TR/2016/WD-webauthn-20160928/
Previous Version: https://www.w3.org/TR/2016/WD-webauthn-20160902/
Previous Version: https://www.w3.org/TR/2016/WD-webauthn-20160531/
Shortname: webauthn
Level:
Editor: Vijay Bharadwaj, w3cid 55440, Microsoft, vijay.bharadwaj@microsoft.com
Editor: Hubert Le Van Gong, w3cid 84817, PayPal, hlevangong@paypal.com
Editor: Dirk Balfanz, w3cid 47648, Google, balfanz@google.com
Editor: Alexei Czeskis, w3cid 87258, Google, aczeskis@google.com
Editor: Arnar Birgisson, w3cid 87332, Google, arnarb@google.com
Editor: Jeff Hodges, w3cid 43843, PayPal, Jeff.Hodges@paypal.com
Editor: Michael B. Jones, w3cid 38745, Microsoft, mbj@microsoft.com
Editor: Rolf Lindemann, w3cid 84447, Nok Nok Labs, rolf@noknok.com
Editor: J.C. Jones, w3cid 87240, Mozilla, jc@mozilla.com
group: webauthn
Issue Tracking: Github https://github.com/w3c/webauthn/issues
!Tests: <a href=https://github.com/w3c/web-platform-tests/tree/master/webauthn>web-platform-tests webauthn/</a> (<a href=https://github.com/w3c/web-platform-tests/labels/webauthn>ongoing work</a>)
Text Macro: RP Relying Party
Text Macro: RPS Relying Parties
Text Macro: INFORMATIVE <em>This section is not normative.</em>
Text Macro: WAC WebAuthn Client
Ignored Vars: op, alg, type, algorithm
Abstract: This specification defines an API enabling the creation and use of strong, attested, scoped, public key-based
credentials by web applications, for the purpose of strongly authenticating users. Conceptually, one or more [=public key
credentials=], each scoped to a given [=Relying Party=], are created and stored on an [=authenticator=] by the user agent in
conjunction with the web application. The user agent mediates access to [=public key credentials=] in order to preserve user
privacy. [=Authenticators=] are responsible for ensuring that no operation is performed without [=user consent=].
[=Authenticators=] provide cryptographic proof of their properties to [=relying parties=] via [=attestation=]. This
specification also describes the functional model for WebAuthn conformant [=authenticators=], including their signature and
[=attestation=] functionality.
Boilerplate: omit conformance, omit feedback-header
Markup Shorthands: css off, markdown on
</pre>
<pre class="anchors">
spec: ECMAScript; urlPrefix: https://tc39.github.io/ecma262/#
type: method
for: JSON; text: stringify; url: sec-json.stringify
type: dfn
text: %ArrayBuffer%; url: sec-arraybuffer-constructor
text: internal slot; url: sec-object-internal-methods-and-internal-slots
<!-- spec: HTML; urlPrefix: https://html.spec.whatwg.org/multipage/ -->
spec: HTML52; urlPrefix: https://w3c.github.io/html/
type: dfn
urlPrefix: browsers.html
text: origin; url: concept-cross-origin
text: opaque origin; url: opaque-origin
text: tuple origin
spec: TokenBinding; urlPrefix: https://tools.ietf.org/html/draft-ietf-tokbind-protocol#
type: dfn
text: Token Binding
text: Token Binding ID; url: section-3.2
spec: WebCryptoAPI; urlPrefix: https://www.w3.org/TR/WebCryptoAPI/
type: dfn
text: normalizing an algorithm; url: dfn-normalize-an-algorithm
text: recognized algorithm name
type: dictionary
text: AlgorithmIdentifier; url: dfn-AlgorithmIdentifier
<!-- Remove these once Shepherd picks up the changes -->
spec: CREDENTIAL-MANAGEMENT-1; urlPrefix: https://w3c.github.io/webappsec-credential-management/
type: dictionary
text: CredentialCreationOptions; url: dictdef-credentialcreationoptions
for: Credential
type: method
text: [[Create]](options)
for: CredentialsContainer
type: method
text: create(); url: dom-credentialscontainer-create
</pre> <!-- class=anchors -->
<pre class="link-defaults">
spec:html; type:dfn; for:environment settings object; text:global object
spec:infra; type:dfn; text:list
spec:url; type:dfn; text:domain
spec:webappsec-credential-management-1; type:dictionary; for:/; text:CredentialRequestOptions
spec:webidl; type:interface; text:Promise
</pre>
# Introduction # {#intro}
[INFORMATIVE]
This specification defines an API enabling the creation and use of strong, attested, scoped, public key-based
credentials by web applications, for the purpose of strongly authenticating users. A [=public key credential=] is
created and stored by an <em>[=authenticator=]</em> at the behest of a <em>[=[RP]=]</em>, subject to <em>[=user
consent=]</em>. Subsequently, the [=public key credential=] can only be accessed by [=origins=] belonging to that [=[RP]=].
This scoping is enforced jointly by <em>[=conforming User Agents=]</em> and <em>[=authenticators=]</em>.
Additionally, privacy across [=[RPS]=] is maintained; [=[RPS]=] are not able to detect any properties, or even
the existence, of credentials scoped to other [RPS].
[=[RPS]=] employ the [=Web Authentication API=] during two distinct, but related, [=ceremonies=] involving a user. The first
is [=Registration=], where a [=public key credential=] is created on an [=authenticator=], and associated by a [=[RP]=]
with the present user's account (the account may already exist or may be created at this time). The second is
[=Authentication=], where the [=[RP]=] is presented with an <em>[=Authentication Assertion=]</em> proving the presence
and consent of the user who registered the [=public key credential=]. Functionally, the [=Web Authentication API=] comprises
a {{PublicKeyCredential}} which extends the Credential Management API [[CREDENTIAL-MANAGEMENT-1]], and infrastructure which
allows those credentials to be used with {{CredentialsContainer/create()|navigator.credentials.create()}} and
{{CredentialsContainer/get()|navigator.credentials.get()}}. The former is used during [=Registration=], and the
latter during [=Authentication=].
Broadly, compliant [=authenticators=] protect [=public key credentials=], and interact with user agents to implement the
[=Web Authentication API=]. Some authenticators may run on the same computing device (e.g., smart phone, tablet, desktop PC) as
the user agent is running on. For instance, such an authenticator might consist of a Trusted Execution Environment (TEE) applet,
a Trusted Platform Module (TPM), or a Secure Element (SE) integrated into the computing device in conjunction with some means
for [=user verification=], along with appropriate platform software to mediate access to these components' functionality. Other
authenticators may operate autonomously from the computing device running the user agent, and be accessed over a transport such
as Universal Serial Bus (USB), Bluetooth Low Energy (BLE) or Near Field Communications (NFC).
## Use Cases ## {#use-cases}
The below use case scenarios illustrate use of two very different types of [=authenticators=], as well as outline further
scenarios. Additional scenarios, including sample code, are given later in [[#sample-scenarios]].
### Registration ### {#usecase-registration}
- On a phone:
* User navigates to example.com in a browser and signs in to an existing account using whatever method they have been using
(possibly a legacy method such as a password), or creates a new account.
* The phone prompts, "Do you want to register this device with example.com?"
* User agrees.
* The phone prompts the user for a previously configured [=authorization gesture=] (PIN, biometric, etc.); the user
provides this.
* Website shows message, "Registration complete."
### Authentication ### {#usecase-authentication}
- On a laptop or desktop:
* User navigates to example.com in a browser, sees an option to "Sign in with your phone."
* User chooses this option and gets a message from the browser, "Please complete this action on your phone."
- Next, on their phone:
* User sees a discrete prompt or notification, "Sign in to example.com."
* User selects this prompt / notification.
* User is shown a list of their example.com identities, e.g., "Sign in as Alice / Sign in as Bob."
* User picks an identity, is prompted for an [=authorization gesture=] (PIN, biometric, etc.) and provides this.
- Now, back on the laptop:
* Web page shows that the selected user is signed-in, and navigates to the signed-in page.
### Other use cases and configurations ### {#other-configurations}
A variety of additional use cases and configurations are also possible, including (but not limited to):
- A user navigates to example.com on their laptop, is guided through a flow to create and register a credential on their phone.
- A user obtains an discrete, [=roaming authenticator=], such as a "fob" with USB or USB+NFC/BLE connectivity options, loads
example.com in their browser on a laptop or phone, and is guided though a flow to create and register a credential on the
fob.
- A [=[RP]=] prompts the user for their [=authorization gesture=] in order to authorize a single transaction, such as a payment
or other financial transaction.
# Conformance # {#conformance}
This specification defines criteria for a [=Conforming User Agent=]: A User Agent MUST behave as described in this
specification in order to be considered conformant. [=Conforming User Agents=] MAY implement algorithms given in this
specification in any way desired, so long as the end result is indistinguishable from the result that would be obtained by the
specification's algorithms. A conforming User Agent MUST also be a conforming implementation of the IDL fragments of this
specification, as described in the “Web IDL” specification. [[!WebIDL-1]]
This specification also defines a model of a conformant [=authenticator=] (see [[#authenticator-model]]). This is a set of
functional and security requirements for an authenticator to be usable by a [=Conforming User Agent=]. As described in
[[#use-cases]], an authenticator may be implemented in the operating system underlying the User Agent, or in external hardware,
or a combination of both.
## Dependencies ## {#dependencies}
This specification relies on several other underlying specifications, listed
below and in [[#index-defined-elsewhere]].
: Base64url encoding
:: The term <dfn>Base64url Encoding</dfn> refers to the base64 encoding using the URL- and filename-safe character set defined
in Section 5 of [[!RFC4648]], with all trailing '=' characters omitted (as permitted by Section 3.2) and without the
inclusion of any line breaks, whitespace, or other additional characters.
: CBOR
:: A number of structures in this specification, including attestation statements and extensions, are encoded using the Compact
Binary Object Representation (<dfn>CBOR</dfn>) [[!RFC7049]].
: CDDL
:: This specification describes the syntax of all CBOR-encoded data using the CBOR Data Definition Language (CDDL) [[!CDDL]].
: Credential Management
:: The API described in this document is an extension of the {{Credential}} concept defined in [[!CREDENTIAL-MANAGEMENT-1]].
: DOM
:: {{DOMException}} and the DOMException values used in this specification are defined in [[!DOM4]].
: ECMAScript
:: [=%ArrayBuffer%=] is defined in [[!ECMAScript]].
: HTML
:: The concepts of [=relevant settings object=], [=origin=],
[=opaque origin=], and [=is a registrable domain suffix of or is equal to=] are defined in [[!HTML52]].
: Web Cryptography API
:: The {{AlgorithmIdentifier}} type and the method for [=normalizing an algorithm=] are defined in
[[WebCryptoAPI#algorithm-dictionary]].
: Web IDL
:: Many of the interface definitions and all of the IDL in this specification depend on [[!WebIDL-1]]. This updated version of
the Web IDL standard adds support for {{Promise}}s, which are now the preferred mechanism for asynchronous
interaction in all new web APIs.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in [[!RFC2119]].
# Terminology # {#terminology}
: <dfn>Assertion</dfn>
:: See [=Authentication Assertion=].
: <dfn>Attestation</dfn>
:: Generally, <em>attestation</em> is a statement serving to bear witness, confirm, or authenticate.
In the WebAuthn context, [=attestation=] is employed to <em>attest</em> to the <em>provenance</em> of an [=authenticator=]
and the data it emits; including, for example: credential IDs, [=credential key pairs=], signature counters, etc. An
[=attestation statement=] is conveyed in an [=attestation object=] during [=registration=]. See also [[#sctn-attestation]]
and [Figure 3](#fig-attStructs).
: <dfn>Attestation Certificate</dfn>
:: A X.509 Certificate for the <dfn>attestation key pair</dfn> used by an [=authenticator=] to attest to its manufacture
and capabilities. At [=registration=] time, the [=authenticator=] uses the <dfn>attestation private key</dfn> to sign
the [=[RP]=]-specific [=credential public key=] (and additional data) that it generates and returns via the
[=authenticatorMakeCredential=] operation. [=[RPS]=] use the <dfn>attestation public key</dfn> conveyed in the [=attestation
certificate=] to verify the [=attestation signature=]. Note that in the case of [=self attestation=], the
[=authenticator=] has no distinct [=attestation key pair=] nor [=attestation certificate=], see [=self
attestation=] for details.
: <dfn>Authentication</dfn>
:: The [=ceremony=] where a user, and the user's computing device(s) (containing at least one [=authenticator=]) work in
concert to cryptographically prove to an [=[RP]=] that the user controls the [=credential private key=] associated with a
previously-registered [=public key credential=] (see [=Registration=]). Note that this typically includes employing a [=test
of user presence=] or [=user verification=].
: <dfn>Authentication Assertion</dfn>
:: The cryptographically signed {{AuthenticatorAssertionResponse}} object returned by an [=authenticator=] as the result of a
[=authenticatorGetAssertion=] operation.
: <dfn>Authenticator</dfn>
:: A cryptographic device used by a [=[WAC]=] to (i) generate a [=public key credential=] and register it with a [=[RP]=],
and (ii) subsequently used to cryptographically sign and return, in the form of an [=Authentication Assertion=], a
challenge and other data presented by a [=[RP]=] (in concert with the [=[WAC]=]) in order to effect
[=authentication=].
: <dfn>Authorization Gesture</dfn>
:: An [=authorization gesture=] is a physical interaction performed by a user with an authenticator as part of a [=ceremony=],
such as [=registration=] or [=authentication=]. By making such an [=authorization gesture=], a user [=user consent|provides
consent=] for (i.e., <em>authorizes</em>) a [=ceremony=] to proceed. This may involve [=user verification=] if the
employed [=authenticator=] is capable, or it may involve a simple [=test of user presence=].
: <dfn>Biometric Recognition</dfn
:: The automated recognition of individuals based on their biological and behavioral characteristics [[ISOBiometricVocabulary]].
: <dfn>Ceremony</dfn>
:: The concept of a [=ceremony=] [[Ceremony]] is an extension of the concept of a network protocol, with human nodes alongside
computer nodes and with communication links that include user interface(s), human-to-human communication, and transfers of
physical objects that carry data. What is out-of-band to a protocol is in-band to a ceremony. In this specification,
[=Registration=] and [=Authentication=] are ceremonies, and an [=authorization gesture=] is often a component of
those [=ceremonies=].
: <dfn>Client</dfn>
:: See [=Conforming User Agent=].
: <dfn>Client-Side</dfn>
:: This refers in general to the combination of the user's platform device, user agent, authenticators, and everything gluing
it all together.
: <dfn>Client-side-resident Credential Private Key</dfn>
:: A [=Client-side-resident Credential Private Key=] is stored either on the client platform, or in some cases on the
authenticator itself, e.g., in the case of a discrete first-factor roaming authenticator. Such <dfn>client-side credential
private key storage</dfn> has the property that the authenticator is able to select the [=credential private key=] given
only an RP ID, possibly with user assistance (e.g., by providing the user a pick list of credentials associated with the RP
ID). By definition, the private key is always exclusively controlled by the Authenticator. In the case of a
[=Client-side-resident Credential Private Key=], the Authenticator might offload storage of wrapped key material to the
client platform, but the client platform is not expected to offload the key storage to remote entities (e.g. RP Server).
: <dfn>Conforming User Agent</dfn>
:: A user agent implementing, in conjunction with the underlying platform, the [=Web Authentication API=] and algorithms
given in this specification, and handling communication between [=authenticators=] and [=[RPS]=].
: <dfn>Credential Public Key</dfn>
:: The public key portion of an [=[RP]=]-specific <dfn>credential key pair</dfn>, generated by an [=authenticator=] and
returned to an [=[RP]=] at [=registration=] time (see also [=public key credential=]). The private key portion of the
[=credential key pair=] is known as the <dfn>credential private key</dfn>. Note that in the case of [=self
attestation=], the [=credential key pair=] is also used as the [=attestation key pair=], see [=self attestation=]
for details.
: <dfn>Registration</dfn>
:: The [=ceremony=] where a user, a [=[RP]=], and the user's computing device(s) (containing at least one
[=authenticator=]) work in concert to create a [=public key credential=] and associate it with the user's [=[RP]=] account.
Note that this typically includes employing a [=test of user presence=] or [=user verification=].
: <dfn>[RP]</dfn>
:: The entity whose web application utilizes the [=Web Authentication API=] to register and authenticate users. See
[=Registration=] and [=Authentication=], respectively.
Note: While the term [=[RP]=] is used in other contexts (e.g., X.509 and OAuth), an entity acting as a [=[RP]=] in one
context is not necessarily a [=[RP]=] in other contexts.
: <dfn>Relying Party Identifier</dfn>
: <dfn>RP ID</dfn>
:: A [=domain=] identifier for the [=[RP]=] on whose behalf a given [=registration=] or
[=authentication|authentication ceremony=] is being performed. A [=RP ID=] MUST be a [=valid domain string=]. A [=public key
credential=] can only be used for [=authentication=] with the same entity (as identified by [=RP ID=]) it was registered
with. By default, the [=RP ID=] for a WebAuthn operation is set to the {{CredentialsContainer}} object's [=relevant settings
object=]'s [=environment settings object/origin=]'s [=effective domain=], i.e., the caller's [=environment settings
object/origin=]'s [=effective domain=]. This default MAY be overridden by the caller, as long as the caller-specified [=RP
ID=] value [=is a registrable domain suffix of or is equal to=] the caller's [=environment settings object/origin=]'s
[=effective domain=]. See also [[#createCredential]] and [[#getAssertion]].
: <dfn>Public Key Credential</dfn>
:: Generically, a <em>credential</em> is data one entity presents to another in order to <em>authenticate</em> the former to the
latter [[RFC4949]]. A WebAuthn <em>[=public key credential=]</em> is a <code>{ identifier, type }</code> pair identifying
authentication information established by the [=authenticator=] and the [=[RP]=], together, at [=registration=] time. The
authentication information consists of an asymmetric key pair, where the [=credential public key|public key portion=] is
returned to the [=[RP]=], who then stores it in conjunction with the present user's account. The [=authenticator=] maps the
[=credential private key|private key portion=] to the [=[RP]=]'s [=RP ID=] and stores it. Subsequently, only that [=[RP]=],
as identified by its [=RP ID=], is able to employ the [=public key credential=] in [=authentication|authentication
ceremonies=], via the {{CredentialsContainer/get()}} method. The [=[RP]=] uses its stored copy of the [=credential public
key=] to verify the resultant [=authentication assertion=].
: <dfn>Test of User Presence</dfn>
: <dfn>TUP</dfn>
:: A [=test of user presence=] is a simple form of [=authorization gesture=] and technical process where a user interacts with
an [=authenticator=] by (typically) simply touching it (other modalities may also exist), yielding a boolean result. Note
that this does not constitute [=user verification=] because [=TUP=], by definition, is not capable of [=biometric
recognition=], nor does it involve the presentation of a shared secret such as a password or PIN.
: <dfn>User Consent</dfn>
:: User consent means the user agrees with what they are being asked, i.e., it encompasses reading and understanding prompts.
An [=authorization gesture=] is a [=ceremony=] component often employed to indicate [=user consent=].
: <dfn>User Verification</dfn>
:: The technical process by which an [=authenticator=] <em>locally authorizes</em> the invocation of the
[=authenticatorMakeCredential=] and [=authenticatorGetAssertion=] operations. [=User verification=] may be instigated
through various [=authorization gesture=] modalities; for example, through a touch plus pin code, password entry, or
[=biometric recognition=] (e.g., presenting a fingerprint) [[ISOBiometricVocabulary]]. The intent is to be able to
distinguish individual users. Note that invocation of the [=authenticatorMakeCredential=] and
[=authenticatorGetAssertion=] operations implies use of key material managed by the authenticator. Note that for
security, [=user verification=] and use of [=credential private keys=] must occur within a single logical security boundary
defining the [=authenticator=].
: <dfn id=concept-user-verified>User Verified</dfn>
:: Upon successful completion of a [=user verification=] process, the user is said to be "verified".
: <dfn>[WAC]</dfn>
:: Also referred to herein as simply a [=client=]. See also [=Conforming User Agent=].
# <dfn>Web Authentication API</dfn> # {#api}
This section normatively specifies the API for creating and using [=public key credentials=]. The basic
idea is that the credentials belong to the user and are managed by an authenticator, with which the [=[RP]=] interacts through the
client (consisting of the browser and underlying OS platform). Scripts can (with the user's consent) request the browser to
create a new credential for future use by the [=[RP]=]. Scripts can also request the user’s permission to perform authentication
operations with an existing credential. All such operations are performed in the authenticator and are mediated by the browser
and/or platform on the user's behalf. At no point does the script get access to the credentials themselves; it only gets
information about the credentials in the form of objects.
In addition to the above script interface, the authenticator may implement (or come with client software that implements) a user
interface for management. Such an interface may be used, for example, to reset the authenticator to a clean state or to inspect
the current state of the authenticator. In other words, such an interface is similar to the user interfaces provided by browsers
for managing user state such as history, saved passwords and cookies. Authenticator management actions such as credential
deletion are considered to be the responsibility of such a user interface and are deliberately omitted from the API exposed to
scripts.
The security properties of this API are provided by the client and the authenticator working together. The authenticator, which
holds and manages credentials, ensures that all operations are scoped to a particular [=origin=], and cannot be replayed against
a different [=origin=], by incorporating the [=origin=] in its responses. Specifically, as defined in [[#authenticator-ops]],
the full [=origin=] of the requester is included, and signed over, in the [=attestation object=] produced when a new credential
is created as well as in all assertions produced by WebAuthn credentials.
Additionally, to maintain user privacy and prevent malicious [=[RPS]=] from probing for the presence of [=public key
credentials=] belonging to other [=[RPS]=], each [=public key credential|credential=] is also associated with a [=Relying Party
Identifier=], or [=RP ID=]. This [=RP ID=] is provided by the client to the [=authenticator=] for all operations, and the
[=authenticator=] ensures that [=public key credential|credentials=] created by a [=[RP]=] can only be used in operations
requested by the same [=RP ID=]. Separating the [=origin=] from the [=RP ID=] in this way allows the API to be used in cases
where a single [=[RP]=] maintains multiple [=origins=].
The client facilitates these security measures by providing correct [=origins=] and [=RP IDs=] to the [=authenticator=] for each
operation. Since this is an integral part of the WebAuthn security model, user agents MUST only expose this API to callers in
[=secure contexts=].
The Web Authentication API is defined by the union of the Web IDL fragments presented in the following sections. A combined IDL
listing is given in the [[#idl-index]].
## <dfn interface>PublicKeyCredential</dfn> Interface ## {#iface-pkcredential}
The {{PublicKeyCredential}} interface inherits from {{Credential}} [[!CREDENTIAL-MANAGEMENT-1]], and contains the attributes
that are returned to the caller when a new credential is created, or a new assertion is requested.
<xmp class="idl">
[SecureContext]
interface PublicKeyCredential : Credential {
readonly attribute ArrayBuffer rawId;
readonly attribute AuthenticatorResponse response;
readonly attribute AuthenticationExtensions clientExtensionResults;
};
</xmp>
<dl dfn-type="attribute" dfn-for="PublicKeyCredential">
: {{Credential/id}}
:: This attribute is inherited from {{Credential}}, though {{PublicKeyCredential}} overrides {{Credential}}'s getter,
instead returning the [=base64url encoding=] of the data contained in the object's
{{PublicKeyCredential/[[identifier]]}} [=internal slot=].
: {{PublicKeyCredential/rawId}}
:: This attribute returns the {{ArrayBuffer}} contained in the {{PublicKeyCredential/[[identifier]]}} internal slot.
: <dfn>response</dfn>
:: This attribute contains the [=authenticator=]'s response to the client's request to either create a [=public key
credential=], or generate an [=authentication assertion=]. If the {{PublicKeyCredential}} is created in response to
{{CredentialsContainer/create()}}, this attribute's value will be an {{AuthenticatorAttestationResponse}}, otherwise,
the {{PublicKeyCredential}} was created in response to {{CredentialsContainer/get()}}, and this attribute's value
will be an {{AuthenticatorAssertionResponse}}.
: <dfn>clientExtensionResults</dfn>
:: This attribute contains a [=map=] containing [=extension identifier=] → [=client extension output=] entries
produced by the extension's [=client extension processing=].
: <dfn>\[[type]]</dfn>
:: The {{PublicKeyCredential}} [=interface object=]'s {{Credential/[[type]]}} [=internal slot=]'s value is the string
"`public-key`".
Note: This is reflected via the {{Credential/type}} attribute getter inherited from {{Credential}}.
: <dfn>\[[discovery]]</dfn>
:: The {{PublicKeyCredential}} [=interface object=]'s {{Credential/[[discovery]]}} [=internal slot=]'s value is
"{{Credential/[[discovery]]/remote}}".
: <dfn>\[[identifier]]</dfn>
:: This [=internal slot=] contains an identifier for the credential, chosen by the platform with help from the
authenticator. This identifier is used to look up credentials for use, and is therefore expected to be globally unique
with high probability across all credentials of the same type, across all authenticators. This API does not constrain
the format or length of this identifier, except that it must be sufficient for the platform to uniquely select a key.
For example, an authenticator without on-board storage may create identifiers containing a [=credential private key=]
wrapped with a symmetric key that is burned into the authenticator.
</dl>
{{PublicKeyCredential}}'s [=interface object=] inherits {{Credential}}'s implementation of
{{Credential/[[CollectFromCredentialStore]](options)}} and {{Credential/[[Store]](credential)}}, and defines its own
implementation of {{PublicKeyCredential/[[DiscoverFromExternalSource]](options)}} and
{{PublicKeyCredential/[[Create]](options)}}.
### `CredentialCreationOptions` Extension ### {#credentialcreationoptions-extension}
To support registration via {{CredentialsContainer/create()|navigator.credentials.create()}}, this document extends
the {{CredentialCreationOptions}} dictionary as follows:
<pre class="idl">
partial dictionary CredentialCreationOptions {
MakeCredentialOptions? publicKey;
};
</pre>
### `CredentialRequestOptions` Extension ### {#credentialrequestoptions-extension}
To support obtaining assertions via {{CredentialsContainer/get()|navigator.credentials.get()}}, this document extends the
{{CredentialRequestOptions}} dictionary as follows:
<pre class="idl">
partial dictionary CredentialRequestOptions {
PublicKeyCredentialRequestOptions? publicKey;
};
</pre>
### Create a new credential - PublicKeyCredential's `[[Create]](options)` method ### {#createCredential}
{{PublicKeyCredential}}'s [=interface object=]'s implementation of the
<dfn for="PublicKeyCredential" method>\[[Create]](options)</dfn> method allows scripts to call
{{CredentialsContainer/create()|navigator.credentials.create()}} to request the creation of a new [=credential key pair=]
and {{PublicKeyCredential}}, managed by an [=authenticator=]. The user agent will prompt the user for [=user consent|consent=].
On success, the returned {{promise}} will be resolved with a {{PublicKeyCredential}} containing an
{{AuthenticatorAttestationResponse}} object.
Note: This algorithm is synchronous; the {{Promise}} resolution/rejection is handled by
{{CredentialsContainer/create()|navigator.credentials.create()}}.
This method accepts a single argument:
<dl dfn-type="argument" dfn-for="PublicKeyCredential/[[Create]](options)">
: <dfn>options</dfn>
:: This argument is a {{CredentialCreationOptions}} object whose |options|["{{CredentialCreationOptions/publicKey}}"]
member contains a {{MakeCredentialOptions}} object specifying how the credential is to be made.
</dl>
When this method is invoked, the user agent MUST execute the following algorithm:
1. Assert: |options|["{{CredentialCreationOptions/publicKey}}"] is [=present=].
1. Let |options| be the value of |options|["{{CredentialCreationOptions/publicKey}}"].
1. If any of the {{PublicKeyCredentialEntity/name}} member of |options|.{{MakeCredentialOptions/rp}}, the
{{PublicKeyCredentialEntity/name}} member of |options|.{{MakeCredentialOptions/user}},
the {{PublicKeyCredentialUserEntity/displayName}} member of |options|.{{MakeCredentialOptions/user}},
or the {{PublicKeyCredentialEntity/id}}
member of |options|.{{MakeCredentialOptions/user}} are [=present|not present=], return a {{TypeError}} [=simple exception=].
1. If the {{MakeCredentialOptions/timeout}} member of |options| is [=present=], check if its value lies within a
reasonable range as defined by the platform and if not, correct it to the closest value lying within that range. Set
|adjustedTimeout| to this adjusted value. If the {{MakeCredentialOptions/timeout}} member of |options| is [=present|not
present=], then set |adjustedTimeout| to a platform-specific default.
1. Let |global| be the {{PublicKeyCredential}} [=interface object=]'s [=global object|environment settings object's global
object=].
1. Let |callerOrigin| be the [=environment settings object/origin=] specified by this {{PublicKeyCredential}} [=interface
object=]'s [=relevant settings object=]. If |callerOrigin| is an [=opaque origin=], return a {{DOMException}} whose name is
"{{NotAllowedError}}", and terminate this algorithm.
1. Let |effectiveDomain| be the |callerOrigin|'s [=effective domain=]. If |effectiveDomain| is null, then return a
{{DOMException}} whose name is "{{SecurityError}}" and terminate this algorithm.
1. If |options|.{{MakeCredentialOptions/rp}}.{{PublicKeyCredentialEntity/id}} is [=present|not present=], then set
|rpId| to |effectiveDomain|.
Otherwise:
1. If |options|.{{MakeCredentialOptions/rp}}.{{PublicKeyCredentialEntity/id}} [=is not a registrable domain suffix of and is
not equal to=] |effectiveDomain|, return a {{DOMException}} whose name is "{{SecurityError}}", and terminate this
algorithm.
1. Set |rpId| to |options|.{{MakeCredentialOptions/rp}}.{{PublicKeyCredentialEntity/id}}.
Note: |rpId| represents the caller's [=RP ID=]. The [=RP ID=] defaults to being the caller's [=environment settings
object/origin=]'s [=effective domain=] unless the caller has explicitly set
|options|.{{MakeCredentialOptions/rp}}.{{PublicKeyCredentialEntity/id}} when calling {{CredentialsContainer/create()}}.
1. Let |normalizedParameters| be a new [=list=] whose [=list/items=] are pairs of {{PublicKeyCredentialType}} and a
[=dictionary=] type (as returned by [=normalizing an algorithm=]).
1. [=list/For each=] |current| of |options|.{{MakeCredentialOptions/parameters}}:
1. If <code>|current|.{{PublicKeyCredentialParameters/type}}</code> does not contain a {{PublicKeyCredentialType}} supported
by this implementation, then [=continue=].
1. Let |normalizedAlgorithm| be the result of [=normalizing an algorithm=] [[!WebCryptoAPI]], with |alg| set to
<code>|current|.{{algorithm}}</code> and |op| set to `"generateKey"`. If an error occurs during this procedure, then
[=continue=].
1. [=list/Append=] the pair of <code>|current|.{{PublicKeyCredentialParameters/type}}</code> and |normalizedAlgorithm| to
|normalizedParameters|.
1. If |normalizedParameters| [=list/is empty=] and |options|.{{MakeCredentialOptions/parameters}} [=list/is not empty=],
cancel the timer started in step 2, return a {{DOMException}} whose name is "{{NotSupportedError}}", and terminate this
algorithm.
1. Let |clientExtensions| be a new [=map=] and let |authenticatorExtensions| be a new [=map=].
1. If the {{MakeCredentialOptions/extensions}} member of |options| is [=present=], then [=map/for each=]
|extensionId| → |clientExtensionInput| of <code>|options|.{{MakeCredentialOptions/extensions}}</code>:
1. If |extensionId| is not supported by this client platform or is not a [=registration extension=], then [=continue=].
1. [=map/Set=] |clientExtensions|[|extensionId|] to |clientExtensionInput|.
1. If |extensionId| is not an [=authenticator extension=], then [=continue=].
1. Let |authenticatorExtensionInput| be the ([=CBOR=]) result of running |extensionId|'s [=client extension processing=]
algorithm on |clientExtensionInput|. If the algorithm returned an error, [=continue=].
1. [=map/Set=] |authenticatorExtensions|[|extensionId|] to the [=base64url encoding=] of |authenticatorExtensionInput|.
1. Let |collectedClientData| be a new {{CollectedClientData}} instance whose fields are:
: {{CollectedClientData/challenge}}
:: The [=base64url encoding=] of |options|.{{MakeCredentialOptions/challenge}}.
: {{CollectedClientData/origin}}
:: The [=ascii serialization of an origin|serialization of=] |callerOrigin|.
: {{CollectedClientData/hashAlg}}
:: The [=recognized algorithm name=] of the hash algorithm selected by the client for generating the
[=hash of the serialized client data=].
: {{CollectedClientData/tokenBindingId}}
:: The [=Token Binding ID=] associated with |callerOrigin|, if one is available.
: {{CollectedClientData/clientExtensions}}
:: |clientExtensions|
: {{CollectedClientData/authenticatorExtensions}}
:: |authenticatorExtensions|
1. Let |clientDataJSON| be the [=JSON-serialized client data=] constructed from |collectedClientData|.
1. Let |clientDataHash| be the [=hash of the serialized client data=] represented by |clientDataJSON|.
1. Let |currentlyAvailableAuthenticators| be a new [=ordered set=] consisting of all [=authenticators=]
available on this platform.
1. Let |selectedAuthenticators| be a new [=ordered set=].
1. If |currentlyAvailableAuthenticators| [=list/is empty=], return a {{DOMException}} whose name is
"{{NotFoundError}}", and terminate this algorithm.
1. If |options|.{{MakeCredentialOptions/authenticatorSelection}} is [=present|present=], iterate through
|currentlyAvailableAuthenticators| and do the following [=set/for each=] |authenticator|:
1. If {{AuthenticatorSelectionCriteria/attachment}} is [=present|present=] and its value is not equal
to |authenticator|'s attachment modality, [=iteration/continue=].
1. If {{AuthenticatorSelectionCriteria/requireResidentKey}} is set to |true| and the |authenticator|
is not capable of storing a [=Client-Side-Resident Credential Private Key=], [=iteration/continue=].
1. [=set/Append=] |authenticator| to |selectedAuthenticators|.
1. If |selectedAuthenticators| [=list/is empty=], return a {{DOMException}} whose name is
"{{ConstraintError}}", and terminate this algoritm.
1. Let |issuedRequests| be a new [=ordered set=].
1. [=set/For each=] |authenticator| in |currentlyAvailableAuthenticators|:
1. Let |excludeList| be a new [=list=].
1. [=list/For each=] credential |C| in <code>|options|.{{MakeCredentialOptions/excludeList}}</code>:
1. If <code>|C|.{{transports}}</code> [=list/is not empty=], and |authenticator| is connected over a transport not
mentioned in <code>|C|.{{transports}}</code>, the client MAY [=continue=].
1. Otherwise, [=list/Append=] |C| to |excludeList|.
1. [=In parallel=], invoke the [=authenticatorMakeCredential=] operation on |authenticator| with |rpId|,
|clientDataHash|, |options|.{{MakeCredentialOptions/rp}}, |options|.{{MakeCredentialOptions/user}},
|normalizedParameters|, |excludeList|, and |authenticatorExtensions| as parameters.
1. [=set/Append=] |authenticator| to |issuedRequests|.
1. Start a timer for |adjustedTimeout| milliseconds. Then execute the following steps [=in parallel=]. The [=task source=] for
these [=tasks=] is the [=dom manipulation task source=].
1. While |issuedRequests| [=list/is not empty=], perform the following actions depending upon the |adjustedTimeout| timer and
responses from the authenticators:
<dl class="switch">
<dt>If the |adjustedTimeout| timer expires,</dt>
<dd>[=set/For each=] |authenticator| in |issuedRequests| invoke the [=authenticatorCancel=] operation on |authenticator|
and [=set/remove=] |authenticator| from |issuedRequests|.</dd>
<dt>If any |authenticator| returns a status indicating that the user cancelled the operation,</dt>
<dd>
1. [=set/Remove=] |authenticator| from |issuedRequests|.
2. [=set/For each=] remaining |authenticator| in |issuedRequests| invoke the [=authenticatorCancel=] operation on
|authenticator| and [=set/remove=] it from |issuedRequests|.
</dd>
<dt>If any |authenticator| returns an error status,</dt>
<dd>[=set/Remove=] |authenticator| from |issuedRequests|.</dd>
<dt>If any |authenticator| indicates success,</dt>
<dd>
1. [=set/Remove=] |authenticator| from |issuedRequests|.
2. Let |attestationObject| be a new {{ArrayBuffer}}, created using |global|'s [=%ArrayBuffer%=], containing the
bytes of the value returned from the successful [=authenticatorMakeCredential=] operation (which is
<code>attObj</code>, as defined in [[#generating-an-attestation-object]]).
3. Let |id| be |attestationObject|<code>.authData.attestation data.credential ID</code> (see [[#sec-attestation-data]]
and [[#sec-authenticator-data]]).
4. Let |value| be a new {{PublicKeyCredential}} object associated with |global| whose fields are:
: {{PublicKeyCredential/[[identifier]]}}
:: |id|
: {{PublicKeyCredential/response}}
:: A new {{AuthenticatorAttestationResponse}} object associated with |global| whose fields are:
: {{AuthenticatorResponse/clientDataJSON}}
:: A new {{ArrayBuffer}}, created using |global|'s [=%ArrayBuffer%=], containing the bytes of |clientDataJSON|.
: {{AuthenticatorAttestationResponse/attestationObject}}
:: |attestationObject|
: {{PublicKeyCredential/clientExtensionResults}}
:: A new {{AuthenticationExtensions}} object containing the [=extension identifier=] → [=client extension output=]
entries created by running each extension's [=client extension processing=] algorithm to create the [=client
extension outputs=], for each [=client extension=] in {{AuthenticatorResponse/clientDataJSON}}.clientExtensions.
5. [=set/For each=] remaining |authenticator| in |issuedRequests| invoke the [=authenticatorCancel=] operation on
|authenticator| and [=set/remove=] it from |issuedRequests|.
6. Return |value| and terminate this algorithm.
</dd>
</dl>
1. Return a {{DOMException}} whose name is "{{NotAllowedError}}".
During the above process, the user agent SHOULD show some UI to the user to guide them in the process of selecting and
authorizing an authenticator.
</div>
### Use an existing credential - PublicKeyCredential's `[[DiscoverFromExternalSource]](options)` method ### {#getAssertion}
<div link-for-hint="PublicKeyCredential/[[DiscoverFromExternalSource]](options)">
The <dfn for="PublicKeyCredential" method>\[[DiscoverFromExternalSource]](options)</dfn> method is used to discover and use an
existing [=public key credential=], with the user's consent. The script optionally specifies some criteria to indicate what
credentials are acceptable to it. The user agent and/or platform locates credentials matching the specified criteria, and guides
the user to pick one that the script will be allowed to use. The user may choose not to provide a credential even if one is
present, for example to maintain privacy.
Note: This algorithm is synchronous; the {{Promise}} resolution/rejection is taken care of by
{{CredentialsContainer/get()|navigator.credentials.get()}}.
<div class="note">
This method takes the following parameters:
: |options|
:: A {{CredentialRequestOptions}} object, containing a challenge that the selected authenticator is expected to
sign to produce the assertion, and additional options as described in [[#assertion-options]]
</div>
When this method is invoked, the user agent MUST execute the following algorithm:
1. Let |publicKeyOptions| be the value of |options| {{CredentialRequestOptions/publicKey}} member.
1. If the {{PublicKeyCredentialRequestOptions/timeout}} member of |publicKeyOptions| is [=present=], check if its value lies
within a reasonable range as defined by the platform and if not, correct it to the closest value lying within that range.
Set |adjustedTimeout| to this adjusted value. If the {{PublicKeyCredentialRequestOptions/timeout}} member of
|publicKeyOptions| is [=present|not present=], then set |adjustedTimeout| to a platform-specific default.
1. Let |global| be the {{PublicKeyCredential}}'s [=relevant settings object=]'s
[=global object|environment settings object's global object=].
1. Let |callerOrigin| be the [=environment settings object/origin=] of this {{CredentialsContainer}} object's [=relevant
settings object=]. If |callerOrigin| is an [=opaque origin=], return {{DOMException}} whose name is
"{{NotAllowedError}}", and terminate this algorithm.
1. If the {{PublicKeyCredentialRequestOptions/rpId}} member of |publicKeyOptions| is [=present|not present=], then set |rpId| to
|callerOrigin|.
<!-- need to fix in same way -->
Otherwise:
1. Let |effectiveDomain| be the |callerOrigin|'s [=effective domain=].
1. If |effectiveDomain| is null, then return a {{DOMException}} whose name is "{{SecurityError}}" and terminate this
algorithm.
1. If {{PublicKeyCredentialRequestOptions/rpId}} [=is not a registrable domain suffix of and is not equal to=]
|effectiveDomain|, return a {{DOMException}} whose name is "{{SecurityError}}", and terminate this algorithm.
1. Set |rpId| to the {{PublicKeyCredentialRequestOptions/rpId}}.
1. Let |clientExtensions| be a new [=map=] and let |authenticatorExtensions| be a new [=map=].
1. If the {{PublicKeyCredentialRequestOptions/extensions}} member of |publicKeyOptions| is [=present=], then [=map/for each=]
|extensionId| → |clientExtensionInput| of <code>|publicKeyOptions|.{{PublicKeyCredentialRequestOptions/extensions}}</code>:
1. If |extensionId| is not supported by this client platform or is not an [=authentication extension=], then [=continue=].
1. [=map/Set=] |clientExtensions|[|extensionId|] to |clientExtensionInput|.
1. If |extensionId| is not an [=authenticator extension=], then [=continue=].
1. Let |authenticatorExtensionInput| be the ([=CBOR=]) result of running |extensionId|'s [=client extension processing=]
algorithm on |clientExtensionInput|.
If the algorithm returned an error, [=continue=].
1. [=map/Set=] |authenticatorExtensions|[|extensionId|] to the [=base64url encoding=] of |authenticatorExtensionInput|.
1. Let |collectedClientData| be a new {{CollectedClientData}} instance whose fields are:
: {{CollectedClientData/challenge}}
:: The [=base64url encoding=] of |publicKeyOptions|.{{PublicKeyCredentialRequestOptions/challenge}}
: {{origin}}
:: The [=unicode serialization of an origin|unicode serialization=] of |rpId|
<!-- here too -->
: {{hashAlg}}
:: The [=recognized algorithm name=] of the hash algorithm selected by the client for generating the
[=hash of the serialized client data=]
: {{tokenBindingId}}
:: The [=Token Binding ID=] associated with |callerOrigin|, if one is available.
: {{CollectedClientData/clientExtensions}}
:: |clientExtensions|
: {{CollectedClientData/authenticatorExtensions}}
:: |authenticatorExtensions|
1. Let |clientDataJSON| be the [=JSON-serialized client data=] constructed from |collectedClientData|.
1. Let |clientDataHash| be the [=hash of the serialized client data=] represented by |clientDataJSON|.
1. Let |issuedRequests| be a new [=ordered set=].
1. If there are no [=authenticators=] currently available on this platform, return a {{DOMException}} whose name is
"{{NotFoundError}}", and terminate this algorithm.
1. For each |authenticator| currently available on this platform, perform the following steps:
1. Let |credentialList| be a new [=list=].
1. If <code>|publicKeyOptions|.{{PublicKeyCredentialRequestOptions/allowList}}</code> [=list/is not empty=], execute a
platform-specific procedure to determine which, if any, credentials in
<code>|publicKeyOptions|.{{PublicKeyCredentialRequestOptions/allowList}}</code> are present on this |authenticator| by
matching with
<code>|publicKeyOptions|.{{PublicKeyCredentialRequestOptions/allowList}}.{{PublicKeyCredentialDescriptor/id}}</code> and
<code>|publicKeyOptions|.{{PublicKeyCredentialRequestOptions/allowList}}.{{PublicKeyCredentialDescriptor/type}}</code>,
and set |credentialList| to this filtered list.
1. If |credentialList| [=list/is empty=] then [=continue=].
1. [=In parallel=], [=list/for each=] credential |C| in |credentialList|:
1. If <code>|C|.{{transports}}</code> [=list/is not empty=], the client SHOULD select one |transport| from
{{transports}}. Then, using |transport|, invoke the [=authenticatorGetAssertion=] operation on |authenticator|, with
|rpId|, |clientDataHash|, |credentialList|, and |authenticatorExtensions| as parameters.
1. Otherwise, using local configuration knowledge of the appropriate transport to use with |authenticator|, invoke the
[=authenticatorGetAssertion=] operation on |authenticator| with |rpId|, |clientDataHash|, |credentialList|, and
|clientExtensions| as parameters.
1. [=set/Append=] |authenticator| to |issuedRequests|.
1. Start a timer for |adjustedTimeout| milliseconds. Then execute the following steps [=in parallel=]. The [=task source=] for
these [=tasks=] is the [=dom manipulation task source=].
1. While |issuedRequests| [=list/is not empty=], perform the following actions depending upon the |adjustedTimeout| timer and
responses from the authenticators:
<dl class="switch">
<dt>If the |adjustedTimeout| timer expires,</dt>
<dd>[=set/For each=] |authenticator| in |issuedRequests| invoke the [=authenticatorCancel=] operation on |authenticator|
and [=set/remove=] |authenticator| from |issuedRequests|.</dd>
<dt>If any |authenticator| returns a status indicating that the user cancelled the operation,</dt>
<dd>
1. [=set/Remove=] |authenticator| from |issuedRequests|.
2. [=set/For each=] remaining |authenticator| in |issuedRequests| invoke the [=authenticatorCancel=] operation on
|authenticator| and [=set/remove=] it from |issuedRequests|.
</dd>
<dt>If any |authenticator| returns an error status,</dt>
<dd>[=set/Remove=] |authenticator| from |issuedRequests|.</dd>
<dt>If any |authenticator| indicates success,</dt>
<dd>
1. [=set/Remove=] |authenticator| from |issuedRequests|.
2. Let |value| be a new {{PublicKeyCredential}} associated with |global| whose fields are:
: {{PublicKeyCredential/[[identifier]]}}
:: A new {{ArrayBuffer}}, created using |global|'s [=%ArrayBuffer%=], containing the bytes of the credential ID
returned from the successful [=authenticatorGetAssertion=] operation, as defined in [[#op-get-assertion]].
: {{PublicKeyCredential/response}}
:: A new {{AuthenticatorAssertionResponse}} object associated with |global| whose fields are:
: {{AuthenticatorResponse/clientDataJSON}}
:: A new {{ArrayBuffer}}, created using |global|'s [=%ArrayBuffer%=], containing the bytes of |clientDataJSON|
: {{AuthenticatorAssertionResponse/authenticatorData}}
:: A new {{ArrayBuffer}}, created using |global|'s [=%ArrayBuffer%=], containing the bytes of the returned
{{authenticatorData}}
: {{AuthenticatorAssertionResponse/signature}}
:: A new {{ArrayBuffer}}, created using |global|'s [=%ArrayBuffer%=], containing the bytes of the returned
{{signature}}
: {{PublicKeyCredential/clientExtensionResults}}
:: A new {{AuthenticationExtensions}} object containing the [=extension identifier=] → [=client extension output=]
entries created by running each extension's [=client extension processing=] algorithm to create the [=client
extension outputs=], for each [=client extension=] in {{AuthenticatorResponse/clientDataJSON}}.clientExtensions.
3. [=set/For each=] remaining |authenticator| in |issuedRequests| invoke the [=authenticatorCancel=] operation on
|authenticator| and [=set/remove=] it from |issuedRequests|.
4. Return |value| and terminate this algorithm.
</dd>
</dl>
1. Return a {{DOMException}} whose name is "{{NotAllowedError}}".
During the above process, the user agent SHOULD show some UI to the user to guide them in the process of selecting and
authorizing an authenticator with which to complete the operation.
</div>
## Authenticator Responses (interface <dfn interface>AuthenticatorResponse</dfn>) ## {#iface-authenticatorresponse}
[=Authenticators=] respond to [=[RP]=] requests by returning an object derived from the
{{AuthenticatorResponse}} interface:
<pre class="idl">
[SecureContext]
interface AuthenticatorResponse {
readonly attribute ArrayBuffer clientDataJSON;
};
</pre>
<div dfn-type="attribute" dfn-for="AuthenticatorResponse">
: <dfn>clientDataJSON</dfn>
:: This attribute contains a [=JSON-serialized client data|JSON serialization=] of the [=client data=] passed to the
authenticator by the client in its call to either {{CredentialsContainer/create()}} or {{CredentialsContainer/get()}}.
</div>
### Information about Public Key Credential (interface <dfn interface>AuthenticatorAttestationResponse</dfn>) ### {#iface-authenticatorattestationresponse}
The {{AuthenticatorAttestationResponse}} interface represents the [=authenticator=]'s response to a client's request
for the creation of a new [=public key credential=]. It contains information about the new credential that can be used to
identify it for later use, and metadata that can be used by the [=[RP]=] to assess the characteristics of the credential
during registration.
<pre class="idl">
[SecureContext]
interface AuthenticatorAttestationResponse : AuthenticatorResponse {
readonly attribute ArrayBuffer attestationObject;
};
</pre>
<div dfn-type="attribute" dfn-for="AuthenticatorAttestationResponse">
: {{AuthenticatorResponse/clientDataJSON}}
:: This attribute, inherited from {{AuthenticatorResponse}}, contains the [=JSON-serialized client data=] (see
[[#sctn-attestation]]) passed to the authenticator by the client in order to generate this credential. The
exact JSON serialization must be preserved, as the [=hash of the serialized client data=] has been computed
over it.
: <dfn>attestationObject</dfn>
:: This attribute contains an [=attestation object=], which is opaque to, and cryptographically protected against
tampering by, the client. The [=attestation object=] contains both [=authenticator data=] and an [=attestation
statement=]. The former contains the AAGUID, a unique credential ID, and the [=credential public key=]. The
contents of the [=attestation statement=] are determined by the [=attestation statement format=] used by the
[=authenticator=]. It also contains any additional information that the [=[RP]=]'s server requires to validate the
[=attestation statement=], as well as to decode and validate the [=authenticator data=] along with the
[=JSON-serialized client data=]. For more details, see [[#sctn-attestation]] as well as
[Figure 3](#fig-attStructs).
</div>
### Web Authentication Assertion (interface <dfn interface>AuthenticatorAssertionResponse</dfn>) ### {#iface-authenticatorassertionresponse}
The {{AuthenticatorAssertionResponse}} interface represents an [=authenticator=]'s response to a client's request for
generation of a new [=authentication assertion=] given the [=[RP]=]'s challenge and optional list of credentials it is
aware of. This response contains a cryptographic signature proving possession of the [=credential private key=], and
optionally evidence of [=user consent=] to a specific transaction.
<pre class="idl">
[SecureContext]
interface AuthenticatorAssertionResponse : AuthenticatorResponse {
readonly attribute ArrayBuffer authenticatorData;
readonly attribute ArrayBuffer signature;
};
</pre>
<div dfn-type="attribute" dfn-for="AuthenticatorAssertionResponse">
: {{AuthenticatorResponse/clientDataJSON}}
:: This attribute, inherited from {{AuthenticatorResponse}}, contains the [=JSON-serialized client data=] (see
[[#sec-client-data]]) passed to the authenticator by the client in order to generate this assertion. The
exact JSON serialization must be preserved, as the [=hash of the serialized client data=] has been computed
over it.
: <dfn>authenticatorData</dfn>
:: This attribute contains the [=authenticator data=] returned by the authenticator. See [[#sec-authenticator-data]].
: <dfn>signature</dfn>
:: This attribute contains the raw signature returned from the authenticator. See [[#op-get-assertion]].
</div>
## Parameters for Credential Generation (dictionary <dfn dictionary>PublicKeyCredentialParameters</dfn>) ## {#credential-params}
<pre class="idl">
dictionary PublicKeyCredentialParameters {
required PublicKeyCredentialType type;
required AlgorithmIdentifier algorithm;
};
</pre>
<div dfn-type="dict-member" dfn-for="PublicKeyCredentialParameters">
This dictionary is used to supply additional parameters when creating a new credential.
The <dfn>type</dfn> member specifies the type of credential to be created.
The <dfn>algorithm</dfn> member specifies the cryptographic signature algorithm with which the newly generated credential
will be used, and thus also the type of asymmetric key pair to be generated, e.g., RSA or Elliptic Curve.
</div>
## User Account Parameters for Credential Generation (dictionary <dfn dictionary>PublicKeyCredentialUserEntity</dfn>) ## {#sctn-user-credential-params}
<pre class="idl">
dictionary PublicKeyCredentialUserEntity : PublicKeyCredentialEntity {
DOMString displayName;
};
</pre>
<div dfn-type="dict-member" dfn-for="PublicKeyCredentialUserEntity">
This dictionary is used to supply additional parameters about the user account when creating a new credential.
The <dfn>displayName</dfn> member contains a friendly name for the user account (e.g., "John P. Smith").
</div>
## Options for Credential Creation (dictionary <dfn dictionary>MakeCredentialOptions</dfn>) ## {#dictionary-makecredentialoptions}
<xmp class="idl">
dictionary MakeCredentialOptions {
required PublicKeyCredentialEntity rp;
required PublicKeyCredentialUserEntity user;
required BufferSource challenge;
required sequence<PublicKeyCredentialParameters> parameters;
unsigned long timeout;
sequence<PublicKeyCredentialDescriptor> excludeList;
AuthenticatorSelectionCriteria authenticatorSelection;
AuthenticationExtensions extensions;
};
</xmp>
<div dfn-type="dict-member" dfn-for="MakeCredentialOptions">
: <dfn>rp</dfn>
:: This member contains data about the [=[RP]=] responsible for the request.
Its value's {{PublicKeyCredentialEntity/name}} member is required, and contains the friendly name of the [=[RP]=]
(e.g. "Acme Corporation", "Widgets, Inc.", or "Awesome Site".
Its value's {{PublicKeyCredentialEntity/id}} member specifies the [=relying party identifier=] with which the credential
should be associated. If omitted, its value will be the {{CredentialsContainer}} object's [=relevant
settings object=]'s [=environment settings object/origin=]'s [=effective domain=].
: <dfn>user</dfn>
:: This member contains data about the user account for which the [=[RP]=] is requesting attestation.
Its value's {{PublicKeyCredentialEntity/name}} member is required, and contains a name for the user account
(e.g., "john.p.smith@example.com" or "+14255551234").
Its value's {{PublicKeyCredentialUserEntity/displayName}} member is required, and contains a friendly name for the user
account (e.g., "John P. Smith").
Its value's {{PublicKeyCredentialEntity/id}} member is required, and contains an identifier for the account, specified