security/AsymmetricFingerprintDialog/template-params.xml

<?xml version="1.0" encoding="UTF-8"?>
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     E.g. Skipping device 'Nexus 5 - MNC', due to different API preview 'MNC' and 'android-MNC'
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<sample>
    <name>AsymmetricFingerprintDialog</name>
    <group>Security</group>
    <package>com.example.android.asymmetricfingerprintdialog</package>

    <minSdk>23</minSdk>

    <dependency>com.squareup.dagger:dagger:1.2.2</dependency>
    <annotationProcessor>com.squareup.dagger:dagger-compiler:1.2.2</annotationProcessor>

    <!-- TODO(thagikura) These dependencies should be created as testCompile instead of compile but
         the template system doesn't allow androidTestCompile dependencies. Change it once fixed.
    -->
    <dependency>junit:junit:4.12</dependency>
    <dependency>org.mockito:mockito-core:1.10.19</dependency>

    <strings>
        <intro>
            <![CDATA[
This sample demonstrates how you can use registered fingerprints to authenticate the user
before proceeding some actions such as purchasing an item. This version uses asymmetric keys.
            ]]>
        </intro>
    </strings>

    <template src="base" />

    <metadata>
        <!-- Values: {DRAFT | PUBLISHED | INTERNAL | DEPRECATED | SUPERCEDED} -->
        <status>PUBLISHED</status>
        <categories>security</categories>
        <technologies>Android</technologies>
        <languages>Java</languages>
        <solutions>Mobile</solutions>
        <level>INTERMEDIATE</level>
        <icon>screenshots/big-icon.png</icon>
        <screenshots>
            <img>screenshots/1-purchase-screen.png</img>
            <img>screenshots/2-fingerprint-dialog.png</img>
            <img>screenshots/3-fingerprint-authenticated.png</img>
            <img>screenshots/4-new-fingerprint-enrolled.png</img>
        </screenshots>

        <api_refs>
            <android>android.hardware.fingerprint.FingerprintManager</android>
            <android>android.hardware.fingerprint.FingerprintManager.AuthenticationCallback</android>
            <android>android.hardware.fingerprint.FingerprintManager.CryptoObject</android>
            <android>android.security.KeyGenParameterSpec</android>
            <android>java.security.KeyStore</android>
            <android>java.security.Signature</android>
            <android>java.security.KeyPairGenerator</android>
        </api_refs>

        <description>
<![CDATA[
A sample that demonstrates to use registered fingerprints to authenticate the user in your app
]]>
        </description>

        <intro>
<![CDATA[
This sample demonstrates how you can use registered fingerprints in your app to authenticate the
user before proceeding some actions such as purchasing an item.

First you need to create an asymmetric key pair in the Android Key Store using [KeyPairGenerator][1]
in the way that its private key can only be used after the user has authenticated with fingerprint
and transmit the public key to your backend with the user verified password (In a real world, the
app should show proper UIs).

By setting [KeyGenParameterSpec.Builder.setUserAuthenticationRequired][2] to true, you can permit the
use of the key only after the user authenticate it including when authenticated with the user's
fingerprint.

Then start listening to a fingerprint on the fingerprint sensor by calling
[FingerprintManager.authenticate][3] with a [Signature][4] initialized with the asymmetric key pair
created. Or alternatively you can fall back to server-side verified password as an authenticator.

Once the fingerprint (or password) is verified, the
[FingerprintManager.AuthenticationCallback#onAuthenticationSucceeded()][5] callback is called.

Then you can verify the purchase transaction on server side with the public key passed from the
client, by verifying the piece of data signed by the Signature.

[1]: https://developer.android.com/reference/java/security/KeyPairGenerator.html
[2]: https://developer.android.com/reference/android/security/keystore/KeyGenParameterSpec.Builder.html#setUserAuthenticationRequired%28boolean%29
[3]: https://developer.android.com/reference/android/hardware/fingerprint/FingerprintManager.html#authenticate%28android.hardware.fingerprint.FingerprintManager.CryptoObject,%20android.os.CancellationSignal,%20int,%20android.hardware.fingerprint.FingerprintManager.AuthenticationCallback,%20android.os.Handler%29
[4]: https://developer.android.com/reference/java/security/Signature.html
[5]: https://developer.android.com/reference/android/hardware/fingerprint/FingerprintManager.AuthenticationCallback.html#onAuthenticationSucceeded%28android.hardware.fingerprint.FingerprintManager.AuthenticationResult%29
]]>
        </intro>
    </metadata>
</sample>