Class3BiometricOrCredentialAuthExtensionsKt

Added in 1.4.0-alpha02

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Kotlin |Java

public final class Class3BiometricOrCredentialAuthExtensionsKt

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Summary

Public methods
static final @NonNull BiometricPrompt.AuthenticationResult	@RequiresApi(value = 30) authenticate(     @NonNull Class3BiometricOrCredentialAuthPrompt receiver,     @NonNull AuthPromptHost host,     BiometricPrompt.CryptoObject crypto ) Shows an authentication prompt to the user.
static final @NonNull BiometricPrompt.AuthenticationResult	@RequiresApi(value = 30) authenticateWithClass3BiometricsOrCredentials(     @NonNull Fragment receiver,     BiometricPrompt.CryptoObject crypto,     @NonNull CharSequence title,     CharSequence subtitle,     CharSequence description,     boolean confirmationRequired ) Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.
static final @NonNull BiometricPrompt.AuthenticationResult	@RequiresApi(value = 30) authenticateWithClass3BiometricsOrCredentials(     @NonNull FragmentActivity receiver,     BiometricPrompt.CryptoObject crypto,     @NonNull CharSequence title,     CharSequence subtitle,     CharSequence description,     boolean confirmationRequired ) Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.
static final @NonNull AuthPrompt	@RequiresApi(value = 30) startClass3BiometricOrCredentialAuthentication(     @NonNull Fragment receiver,     BiometricPrompt.CryptoObject crypto,     @NonNull CharSequence title,     CharSequence subtitle,     CharSequence description,     boolean confirmationRequired,     Executor executor,     @NonNull AuthPromptCallback callback ) Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.
static final @NonNull AuthPrompt	@RequiresApi(value = 30) startClass3BiometricOrCredentialAuthentication(     @NonNull FragmentActivity receiver,     BiometricPrompt.CryptoObject crypto,     @NonNull CharSequence title,     CharSequence subtitle,     CharSequence description,     boolean confirmationRequired,     Executor executor,     @NonNull AuthPromptCallback callback ) Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.

Public methods

authenticate

Artifact: androidx.biometric:biometric-ktx

View Source

@RequiresApi(value = 30)
public static final @NonNull BiometricPrompt.AuthenticationResult authenticate(
    @NonNull Class3BiometricOrCredentialAuthPrompt receiver,
    @NonNull AuthPromptHost host,
    BiometricPrompt.CryptoObject crypto
)

Shows an authentication prompt to the user.

import androidx.biometric.BiometricPrompt
import androidx.biometric.auth.AuthPromptErrorException
import androidx.biometric.auth.AuthPromptFailureException
import androidx.biometric.auth.AuthPromptHost
import androidx.biometric.auth.Class3BiometricOrCredentialAuthPrompt
import androidx.biometric.auth.CredentialAuthPrompt
import androidx.biometric.auth.authenticate

// To use Class3 authentication, we need to create a CryptoObject.
// First create a spec for the key to be generated.
val keyPurpose = KeyProperties.PURPOSE_ENCRYPT or KeyProperties.PURPOSE_DECRYPT
val keySpec =
    KeyGenParameterSpec.Builder(KEY_NAME, keyPurpose)
        .apply {
            setBlockModes(KeyProperties.BLOCK_MODE_CBC)
            setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_PKCS7)
            setUserAuthenticationRequired(true)

            // Require authentication for each use of the key.
            val timeout = 0
            // Set the key type according to the allowed auth types.
            val keyType =
                KeyProperties.AUTH_BIOMETRIC_STRONG or KeyProperties.AUTH_DEVICE_CREDENTIAL
            setUserAuthenticationParameters(timeout, keyType)
        }
        .build()

// Generate and store the key in the Android keystore.
KeyGenerator.getInstance(KeyProperties.KEY_ALGORITHM_AES, KEYSTORE_INSTANCE).run {
    init(keySpec)
    generateKey()
}

// Prepare the crypto object to use for authentication.
val cipher =
    Cipher.getInstance(
            "${KeyProperties.KEY_ALGORITHM_AES}/${KeyProperties.BLOCK_MODE_CBC}/" +
                KeyProperties.ENCRYPTION_PADDING_PKCS7
        )
        .apply {
            val keyStore = KeyStore.getInstance(KEYSTORE_INSTANCE).apply { load(null) }
            init(Cipher.ENCRYPT_MODE, keyStore.getKey(KEY_NAME, null) as SecretKey)
        }

val cryptoObject = BiometricPrompt.CryptoObject(cipher)
val payload = "A message to encrypt".toByteArray(Charset.defaultCharset())

// Construct AuthPrompt with localized Strings to be displayed to UI.
val authPrompt =
    Class3BiometricOrCredentialAuthPrompt.Builder(title)
        .apply {
            setSubtitle(subtitle)
            setDescription(description)
            setConfirmationRequired(true)
        }
        .build()

try {
    val authResult = authPrompt.authenticate(AuthPromptHost(this), cryptoObject)

    // Encrypt a payload using the result of crypto-based auth.
    val encryptedPayload = authResult.cryptoObject?.cipher?.doFinal(payload)

    // Use the encrypted payload somewhere interesting.
    sendEncryptedPayload(encryptedPayload)
} catch (e: AuthPromptErrorException) {
    // Handle irrecoverable error during authentication.
    // Possible values for AuthPromptErrorException.errorCode are listed in the @IntDef,
    // androidx.biometric.BiometricPrompt.AuthenticationError.
} catch (e: AuthPromptFailureException) {
    // Handle auth failure due biometric credentials being rejected.
}

Parameters
@NonNull AuthPromptHost host	A wrapper for the component that will host the prompt.
BiometricPrompt.CryptoObject crypto	A cryptographic object to be associated with this authentication.

Returns
@NonNull BiometricPrompt.AuthenticationResult	AuthenticationResult for a successful authentication.

Throws
androidx.biometric.auth.AuthPromptErrorException	when an unrecoverable error has been encountered and authentication has stopped.
androidx.biometric.auth.AuthPromptFailureException	when an authentication attempt by the user has been rejected.

See also
authenticate	( AuthPromptHost, AuthPromptCallback )

authenticateWithClass3BiometricsOrCredentials

Artifact: androidx.biometric:biometric-ktx

View Source

@RequiresApi(value = 30)
public static final @NonNull BiometricPrompt.AuthenticationResult authenticateWithClass3BiometricsOrCredentials(
    @NonNull Fragment receiver,
    BiometricPrompt.CryptoObject crypto,
    @NonNull CharSequence title,
    CharSequence subtitle,
    CharSequence description,
    boolean confirmationRequired
)

Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.

Parameters
BiometricPrompt.CryptoObject crypto	A cryptographic object to be associated with this authentication.
@NonNull CharSequence title	The title to be displayed on the prompt.
CharSequence subtitle	An optional subtitle to be displayed on the prompt.
CharSequence description	An optional description to be displayed on the prompt.
boolean confirmationRequired	Whether user confirmation should be required for passive biometrics.

Returns
@NonNull BiometricPrompt.AuthenticationResult	AuthenticationResult for a successful authentication.

Throws
androidx.biometric.auth.AuthPromptErrorException	when an unrecoverable error has been encountered and authentication has stopped.
androidx.biometric.auth.AuthPromptFailureException	when an authentication attempt by the user has been rejected.

See also
Class3BiometricOrCredentialAuthPrompt

authenticateWithClass3BiometricsOrCredentials

Artifact: androidx.biometric:biometric-ktx

View Source

@RequiresApi(value = 30)
public static final @NonNull BiometricPrompt.AuthenticationResult authenticateWithClass3BiometricsOrCredentials(
    @NonNull FragmentActivity receiver,
    BiometricPrompt.CryptoObject crypto,
    @NonNull CharSequence title,
    CharSequence subtitle,
    CharSequence description,
    boolean confirmationRequired
)

Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.

Parameters
BiometricPrompt.CryptoObject crypto	A cryptographic object to be associated with this authentication.
@NonNull CharSequence title	The title to be displayed on the prompt.
CharSequence subtitle	An optional subtitle to be displayed on the prompt.
CharSequence description	An optional description to be displayed on the prompt.
boolean confirmationRequired	Whether user confirmation should be required for passive biometrics.

Returns
@NonNull BiometricPrompt.AuthenticationResult	AuthenticationResult for a successful authentication.

Throws
androidx.biometric.auth.AuthPromptErrorException	when an unrecoverable error has been encountered and authentication has stopped.
androidx.biometric.auth.AuthPromptFailureException	when an authentication attempt by the user has been rejected.

See also
Class3BiometricOrCredentialAuthPrompt

startClass3BiometricOrCredentialAuthentication

Artifact: androidx.biometric:biometric-ktx

View Source

Added in 1.4.0-alpha02

@RequiresApi(value = 30)
public static final @NonNull AuthPrompt startClass3BiometricOrCredentialAuthentication(
    @NonNull Fragment receiver,
    BiometricPrompt.CryptoObject crypto,
    @NonNull CharSequence title,
    CharSequence subtitle,
    CharSequence description,
    boolean confirmationRequired,
    Executor executor,
    @NonNull AuthPromptCallback callback
)

Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.

Parameters
BiometricPrompt.CryptoObject crypto	A cryptographic object to be associated with this authentication.
@NonNull CharSequence title	The title to be displayed on the prompt.
CharSequence subtitle	An optional subtitle to be displayed on the prompt.
CharSequence description	An optional description to be displayed on the prompt.
boolean confirmationRequired	Whether user confirmation should be required for passive biometrics.
Executor executor	An executor for callback methods. If null, these will run on the main thread.
@NonNull AuthPromptCallback callback	The object that will receive and process authentication events.

Returns
@NonNull AuthPrompt	An AuthPrompt handle to the shown prompt.

See also
Class3BiometricOrCredentialAuthPrompt

startClass3BiometricOrCredentialAuthentication

Artifact: androidx.biometric:biometric-ktx

View Source

Added in 1.4.0-alpha02

@RequiresApi(value = 30)
public static final @NonNull AuthPrompt startClass3BiometricOrCredentialAuthentication(
    @NonNull FragmentActivity receiver,
    BiometricPrompt.CryptoObject crypto,
    @NonNull CharSequence title,
    CharSequence subtitle,
    CharSequence description,
    boolean confirmationRequired,
    Executor executor,
    @NonNull AuthPromptCallback callback
)

Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris) or the screen lock credential (i.e. PIN, pattern, or password) for the device.

Parameters
BiometricPrompt.CryptoObject crypto	A cryptographic object to be associated with this authentication.
@NonNull CharSequence title	The title to be displayed on the prompt.
CharSequence subtitle	An optional subtitle to be displayed on the prompt.
CharSequence description	An optional description to be displayed on the prompt.
boolean confirmationRequired	Whether user confirmation should be required for passive biometrics.
Executor executor	An executor for callback methods. If null, these will run on the main thread.
@NonNull AuthPromptCallback callback	The object that will receive and process authentication events.

Returns
@NonNull AuthPrompt	An AuthPrompt handle to the shown prompt.

See also
Class3BiometricOrCredentialAuthPrompt