Class3BiometricAuthExtensionsKt
public final class Class3BiometricAuthExtensionsKt
Summary
Public methods |
|
|---|---|
static final @NonNull BiometricPrompt.AuthenticationResult |
authenticate(Shows an authentication prompt to the user. |
static final @NonNull BiometricPrompt.AuthenticationResult |
authenticateWithClass3Biometrics(Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris). |
static final @NonNull BiometricPrompt.AuthenticationResult |
authenticateWithClass3Biometrics(Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris). |
static final @NonNull AuthPrompt |
authenticateWithClass3Biometrics(Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris). |
static final @NonNull AuthPrompt |
authenticateWithClass3Biometrics(Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris). |
Public methods
authenticate
public static final @NonNull BiometricPrompt.AuthenticationResult authenticate(
@NonNull Class3BiometricAuthPrompt 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.Class3BiometricAuthPrompt
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 =
Class3BiometricAuthPrompt.Builder(title, negativeButtonText)
.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 |
|
| 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) |
authenticateWithClass3Biometrics
public static final @NonNull BiometricPrompt.AuthenticationResult authenticateWithClass3Biometrics(
@NonNull Fragment receiver,
BiometricPrompt.CryptoObject crypto,
@NonNull CharSequence title,
@NonNull CharSequence negativeButtonText,
CharSequence subtitle,
CharSequence description,
boolean confirmationRequired
)
Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris).
| Parameters | |
|---|---|
BiometricPrompt.CryptoObject crypto |
A cryptographic object to be associated with this authentication. |
@NonNull CharSequence title |
The title to be displayed on the prompt. |
@NonNull CharSequence negativeButtonText |
The label for the negative button 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 |
|
| 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 | |
|---|---|
Class3BiometricAuthPrompt |
authenticateWithClass3Biometrics
public static final @NonNull BiometricPrompt.AuthenticationResult authenticateWithClass3Biometrics(
@NonNull FragmentActivity receiver,
BiometricPrompt.CryptoObject crypto,
@NonNull CharSequence title,
@NonNull CharSequence negativeButtonText,
CharSequence subtitle,
CharSequence description,
boolean confirmationRequired
)
Prompts the user to authenticate with a Class 3 biometric (e.g. fingerprint, face, or iris).
| Parameters | |
|---|---|
BiometricPrompt.CryptoObject crypto |
A cryptographic object to be associated with this authentication. |
@NonNull CharSequence title |
The title to be displayed on the prompt. |
@NonNull CharSequence negativeButtonText |
The label for the negative button 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 |
|
| 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 | |
|---|---|
Class3BiometricAuthPrompt |
authenticateWithClass3Biometrics
public static final @NonNull AuthPrompt authenticateWithClass3Biometrics(
@NonNull Fragment receiver,
BiometricPrompt.CryptoObject crypto,
@NonNull CharSequence title,
@NonNull CharSequence negativeButtonText,
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).
| Parameters | |
|---|---|
BiometricPrompt.CryptoObject crypto |
A cryptographic object to be associated with this authentication. |
@NonNull CharSequence title |
The title to be displayed on the prompt. |
@NonNull CharSequence negativeButtonText |
The label for the negative button 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 |
@NonNull AuthPromptCallback callback |
The object that will receive and process authentication events. |
| Returns | |
|---|---|
@NonNull AuthPrompt |
An |
| See also | |
|---|---|
Class3BiometricAuthPrompt |
authenticateWithClass3Biometrics
public static final @NonNull AuthPrompt authenticateWithClass3Biometrics(
@NonNull FragmentActivity receiver,
BiometricPrompt.CryptoObject crypto,
@NonNull CharSequence title,
@NonNull CharSequence negativeButtonText,
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).
| Parameters | |
|---|---|
BiometricPrompt.CryptoObject crypto |
A cryptographic object to be associated with this authentication. |
@NonNull CharSequence title |
The title to be displayed on the prompt. |
@NonNull CharSequence negativeButtonText |
The label for the negative button 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 |
@NonNull AuthPromptCallback callback |
The object that will receive and process authentication events. |
| Returns | |
|---|---|
@NonNull AuthPrompt |
An |
| See also | |
|---|---|
Class3BiometricAuthPrompt |