feat: support hints and attestation formats

protocol/attestation.go

@@ -70,11 +70,11 @@ type AttestationObject struct {
 
 type attestationFormatValidationHandler func(AttestationObject, []byte) (string, []interface{}, error)
 
-var attestationRegistry = make(map[string]attestationFormatValidationHandler)
+var attestationRegistry = make(map[AttestationFormat]attestationFormatValidationHandler)
 
 // RegisterAttestationFormat is a method to register attestation formats with the library. Generally using one of the
 // locally registered attestation formats is sufficient.
-func RegisterAttestationFormat(format string, handler attestationFormatValidationHandler) {
+func RegisterAttestationFormat(format AttestationFormat, handler attestationFormatValidationHandler) {
  attestationRegistry[format] = handler
 }
 
@@ -135,15 +135,15 @@ func (attestationObject *AttestationObject) Verify(relyingPartyID string, client
 
  // But first let's make sure attestation is present. If it isn't, we don't need to handle
  // any of the following steps
- if attestationObject.Format == "none" {
+ if AttestationFormat(attestationObject.Format) == AttestationFormatNone {
  if len(attestationObject.AttStatement) != 0 {
  return ErrAttestationFormat.WithInfo("Attestation format none with attestation present")
  }
 
  return nil
  }
 
- formatHandler, valid := attestationRegistry[attestationObject.Format]
+ formatHandler, valid := attestationRegistry[AttestationFormat(attestationObject.Format)]
  if !valid {
  return ErrAttestationFormat.WithInfo(fmt.Sprintf("Attestation format %s is unsupported", attestationObject.Format))
  }

protocol/attestation_androidkey.go

@@ -10,10 +10,8 @@ import (
  "github.com/go-webauthn/webauthn/protocol/webauthncose"
 )
 
-var androidAttestationKey = "android-key"
-
 func init() {
- RegisterAttestationFormat(androidAttestationKey, verifyAndroidKeyFormat)
+ RegisterAttestationFormat(AttestationFormatAndroidKey, verifyAndroidKeyFormat)
 }
 
 // The android-key attestation statement looks like:

protocol/attestation_apple.go

@@ -14,10 +14,8 @@ import (
  "github.com/go-webauthn/webauthn/protocol/webauthncose"
 )
 
-var appleAttestationKey = "apple"
-
 func init() {
- RegisterAttestationFormat(appleAttestationKey, verifyAppleFormat)
+ RegisterAttestationFormat(AttestationFormatApple, verifyAppleFormat)
 }
 
 // The apple attestation statement looks like:

protocol/attestation_packed.go

@@ -12,10 +12,8 @@ import (
  "github.com/go-webauthn/webauthn/protocol/webauthncose"
 )
 
-var packedAttestationKey = "packed"
-
 func init() {
- RegisterAttestationFormat(packedAttestationKey, verifyPackedFormat)
+ RegisterAttestationFormat(AttestationFormatPacked, verifyPackedFormat)
 }
 
 // The packed attestation statement looks like:
@@ -45,13 +43,13 @@ func verifyPackedFormat(att AttestationObject, clientDataHash []byte) (string, [
 
  alg, present := att.AttStatement["alg"].(int64)
  if !present {
- return packedAttestationKey, nil, ErrAttestationFormat.WithDetails("Error retrieving alg value")
+ return string(AttestationFormatPacked), nil, ErrAttestationFormat.WithDetails("Error retrieving alg value")
  }
 
  // Get the sig value - A byte string containing the attestation signature.
  sig, present := att.AttStatement["sig"].([]byte)
  if !present {
- return packedAttestationKey, nil, ErrAttestationFormat.WithDetails("Error retrieving sig value")
+ return string(AttestationFormatPacked), nil, ErrAttestationFormat.WithDetails("Error retrieving sig value")
  }
 
  // Step 2. If x5c is present, this indicates that the attestation type is not ECDAA.

protocol/attestation_safetynet.go

@@ -14,10 +14,8 @@ import (
  "github.com/go-webauthn/webauthn/metadata"
 )
 
-var safetyNetAttestationKey = "android-safetynet"
-
 func init() {
- RegisterAttestationFormat(safetyNetAttestationKey, verifySafetyNetFormat)
+ RegisterAttestationFormat(AttestationFormatAndroidSafetyNet, verifySafetyNetFormat)
 }
 
 type SafetyNetResponse struct {

protocol/attestation_tpm.go

@@ -15,10 +15,8 @@ import (
  "github.com/go-webauthn/webauthn/protocol/webauthncose"
 )
 
-var tpmAttestationKey = "tpm"
-
 func init() {
- RegisterAttestationFormat(tpmAttestationKey, verifyTPMFormat)
+ RegisterAttestationFormat(AttestationFormatTPM, verifyTPMFormat)
 }
 
 func verifyTPMFormat(att AttestationObject, clientDataHash []byte) (string, []interface{}, error) {

protocol/attestation_u2f.go

@@ -11,10 +11,8 @@ import (
  "github.com/go-webauthn/webauthn/protocol/webauthncose"
 )
 
-var u2fAttestationKey = "fido-u2f"
-
 func init() {
- RegisterAttestationFormat(u2fAttestationKey, verifyU2FFormat)
+ RegisterAttestationFormat(AttestationFormatFIDOU2F, verifyU2FFormat)
 }
 
 // verifyU2FFormat - Follows verification steps set out by https://www.w3.org/TR/webauthn/#fido-u2f-attestation

protocol/options.go

@@ -17,34 +17,33 @@ type CredentialAssertion struct {
 // In order to create a Credential via create(), the caller specifies a few parameters in a
 // PublicKeyCredentialCreationOptions object.
 //
-// TODO: There is one field missing from this for WebAuthn Level 3. A string slice named 'attestationFormats'.
-//
 // Specification: §5.4. Options for Credential Creation (https://www.w3.org/TR/webauthn/#dictionary-makecredentialoptions)
 type PublicKeyCredentialCreationOptions struct {
- RelyingParty RelyingPartyEntity `json:"rp"`
- User UserEntity `json:"user"`
- Challenge URLEncodedBase64 `json:"challenge"`
- Parameters []CredentialParameter `json:"pubKeyCredParams,omitempty"`
- Timeout int `json:"timeout,omitempty"`
- CredentialExcludeList []CredentialDescriptor `json:"excludeCredentials,omitempty"`
- AuthenticatorSelection AuthenticatorSelection `json:"authenticatorSelection,omitempty"`
- Attestation ConveyancePreference `json:"attestation,omitempty"`
- Extensions AuthenticationExtensions `json:"extensions,omitempty"`
+ RelyingParty RelyingPartyEntity `json:"rp"`
+ User UserEntity `json:"user"`
+ Challenge URLEncodedBase64 `json:"challenge"`
+ Parameters []CredentialParameter `json:"pubKeyCredParams,omitempty"`
+ Timeout int `json:"timeout,omitempty"`
+ CredentialExcludeList []CredentialDescriptor `json:"excludeCredentials,omitempty"`
+ AuthenticatorSelection AuthenticatorSelection `json:"authenticatorSelection,omitempty"`
+ Hints []PublicKeyCredentialHint `json:"hints,omitempty"`
+ Attestation ConveyancePreference `json:"attestation,omitempty"`
+ AttestationFormats []AttestationFormat `json:"attestationFormats,omitempty"`
+ Extensions AuthenticationExtensions `json:"extensions,omitempty"`
 }
 
 // The PublicKeyCredentialRequestOptions dictionary supplies get() with the data it needs to generate an assertion.
 // Its challenge member MUST be present, while its other members are OPTIONAL.
 //
-// TODO: There are two fields missing from this for WebAuthn Level 3. A string type named 'attestation', and a string
-// slice named 'attestationFormats'.
-//
 // Specification: §5.5. Options for Assertion Generation (https://www.w3.org/TR/webauthn/#dictionary-assertion-options)
 type PublicKeyCredentialRequestOptions struct {
  Challenge URLEncodedBase64 `json:"challenge"`
  Timeout int `json:"timeout,omitempty"`
  RelyingPartyID string `json:"rpId,omitempty"`
  AllowedCredentials []CredentialDescriptor `json:"allowCredentials,omitempty"`
  UserVerification UserVerificationRequirement `json:"userVerification,omitempty"`
+ Attestation ConveyancePreference `json:"attestation,omitempty"`
+ AttestationFormats []AttestationFormat `json:"attestationFormats,omitempty"`
  Extensions AuthenticationExtensions `json:"extensions,omitempty"`
 }
 
@@ -126,6 +125,69 @@ type AuthenticatorSelection struct {
  UserVerification UserVerificationRequirement `json:"userVerification,omitempty"`
 }
 
+// PublicKeyCredentialHint is a type representing the enum PublicKeyCredentialHints from
+// https://www.w3.org/TR/webauthn-3/#enum-hints.
+type PublicKeyCredentialHint string
+
+const (
+ // PublicKeyCredentialHintSecurityKey is a PublicKeyCredentialHint that indicates that the Relying Party believes
+ // that users will satisfy this request with a physical security key. For example, an enterprise Relying Party may
+ // set this hint if they have issued security keys to their employees and will only accept those authenticators for
+ // registration and authentication.
+ //
+ // For compatibility with older user agents, when this hint is used in PublicKeyCredentialCreationOptions, the
+ // authenticatorAttachment SHOULD be set to cross-platform.
+ PublicKeyCredentialHintSecurityKey PublicKeyCredentialHint = "security-key"
+
+ // PublicKeyCredentialHintClientDevice is a PublicKeyCredentialHint that indicates that the Relying Party believes
+ // that users will satisfy this request with a platform authenticator attached to the client device.
+ //
+ // For compatibility with older user agents, when this hint is used in PublicKeyCredentialCreationOptions, the
+ // authenticatorAttachment SHOULD be set to platform.
+ PublicKeyCredentialHintClientDevice PublicKeyCredentialHint = "client-device"
+
+ // PublicKeyCredentialHintHybrid is a PublicKeyCredentialHint that indicates that the Relying Party believes that
+ // users will satisfy this request with general-purpose authenticators such as smartphones. For example, a consumer
+ // Relying Party may believe that only a small fraction of their customers possesses dedicated security keys. This
+ // option also implies that the local platform authenticator should not be promoted in the UI.
+ //
+ // For compatibility with older user agents, when this hint is used in PublicKeyCredentialCreationOptions, the
+ // authenticatorAttachment SHOULD be set to cross-platform.
+ PublicKeyCredentialHintHybrid PublicKeyCredentialHint = "hybrid"
+)
+
+type AttestationFormat string
+
+const (
+ // AttestationFormatPacked is the "packed" attestation statement format is a WebAuthn-optimized format for
+ // attestation. It uses a very compact but still extensible encoding method. This format is implementable by
+ //authenticators with limited resources (e.g., secure elements).
+ AttestationFormatPacked AttestationFormat = "packed"
+
+ // AttestationFormatTPM is the TPM attestation statement format returns an attestation statement in the same format
+ // as the packed attestation statement format, although the rawData and signature fields are computed differently.
+ AttestationFormatTPM AttestationFormat = "tpm"
+
+ // AttestationFormatAndroidKey is the attestation statement format for platform authenticators on versions "N", and
+ // later, which may provide this proprietary "hardware attestation" statement.
+ AttestationFormatAndroidKey AttestationFormat = "android-key"
+
+ // AttestationFormatAndroidSafetyNet is the attestation statement format that Android-based platform authenticators
+ // MAY produce an attestation statement based on the Android SafetyNet API.
+ AttestationFormatAndroidSafetyNet AttestationFormat = "android-safetynet"
+
+ // AttestationFormatFIDOU2F is the attestation statement format that is used with FIDO U2F authenticators.
+ AttestationFormatFIDOU2F AttestationFormat = "fido-u2f"
+
+ // AttestationFormatApple is the attestation statement format that is used with Apple devices' platform
+ // authenticators.
+ AttestationFormatApple AttestationFormat = "apple"
+
+ // AttestationFormatNone is the attestation statement format that is used to replace any authenticator-provided
+ // attestation statement when a WebAuthn Relying Party indicates it does not wish to receive attestation information.
+ AttestationFormatNone AttestationFormat = "none"
+)
+
 // ConveyancePreference is the type representing the AttestationConveyancePreference IDL.
 //
 // WebAuthn Relying Parties may use AttestationConveyancePreference to specify their preference regarding attestation

webauthn/login.go

@@ -115,6 +115,22 @@ func WithUserVerification(userVerification protocol.UserVerificationRequirement)
  }
 }
 
+// WithLoginConveyancePreference adjusts the non-default parameters regarding whether the authenticator should attest to the
+// credential.
+func WithLoginConveyancePreference(preference protocol.ConveyancePreference) LoginOption {
+ return func(cco *protocol.PublicKeyCredentialRequestOptions) {
+ cco.Attestation = preference
+ }
+}
+
+// WithLoginAttestationFormats adjusts the preferred attestation formats for this credential request in most to least
+// preferable. Advisory only.
+func WithLoginAttestationFormats(formats ...protocol.AttestationFormat) LoginOption {
+ return func(cco *protocol.PublicKeyCredentialRequestOptions) {
+ cco.AttestationFormats = formats
+ }
+}
+
 // WithAssertionExtensions adjusts the requested extensions.
 func WithAssertionExtensions(extensions protocol.AuthenticationExtensions) LoginOption {
  return func(cco *protocol.PublicKeyCredentialRequestOptions) {

webauthn/registration.go

@@ -101,21 +101,43 @@ func WithAuthenticatorSelection(authenticatorSelection protocol.AuthenticatorSel
  }
 }
 
+func WithHints(hints ...protocol.PublicKeyCredentialHint) RegistrationOption {
+ return func(cco *protocol.PublicKeyCredentialCreationOptions) {
+ cco.Hints = hints
+ }
+}
+
 // WithExclusions adjusts the non-default parameters regarding credentials to exclude from registration.
 func WithExclusions(excludeList []protocol.CredentialDescriptor) RegistrationOption {
  return func(cco *protocol.PublicKeyCredentialCreationOptions) {
  cco.CredentialExcludeList = excludeList
  }
 }
 
-// WithConveyancePreference adjusts the non-default parameters regarding whether the authenticator should attest to the
-// credential.
+// WithConveyancePreference is a direct alias for WithRegistrationConveyancePreference.
+//
+// Deprecated: Use WithRegistrationConveyancePreference in favor of WithConveyancePreference as this function will be
+// likely be removed in a future release.
 func WithConveyancePreference(preference protocol.ConveyancePreference) RegistrationOption {
+ return WithRegistrationConveyancePreference(preference)
+}
+
+// WithRegistrationConveyancePreference adjusts the non-default parameters regarding whether the authenticator should attest to the
+// credential.
+func WithRegistrationConveyancePreference(preference protocol.ConveyancePreference) RegistrationOption {
  return func(cco *protocol.PublicKeyCredentialCreationOptions) {
  cco.Attestation = preference
  }
 }
 
+// WithRegistrationAttestationFormats adjusts the preferred attestation formats for this credential creation in most to
+// least preferable. Advisory only.
+func WithRegistrationAttestationFormats(formats ...protocol.AttestationFormat) RegistrationOption {
+ return func(cco *protocol.PublicKeyCredentialCreationOptions) {
+ cco.AttestationFormats = formats
+ }
+}
+
 // WithExtensions adjusts the extension parameter in the registration options.
 func WithExtensions(extension protocol.AuthenticationExtensions) RegistrationOption {
  return func(cco *protocol.PublicKeyCredentialCreationOptions) {