Recaptcha: Add QR code verification flow

play-services-recaptcha/core/build.gradle

@@ -6,6 +6,7 @@
 apply plugin: 'com.android.library'
 apply plugin: 'com.squareup.wire'
 apply plugin: 'kotlin-android'
+apply plugin: 'org.jetbrains.kotlin.plugin.compose'
 apply plugin: 'maven-publish'
 apply plugin: 'signing'
 
@@ -20,13 +21,20 @@ dependencies {
     implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutineVersion"
     implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:$coroutineVersion"
 
+    implementation "androidx.appcompat:appcompat:$appcompatVersion"
     implementation "androidx.core:core-ktx:$coreVersion"
     implementation "androidx.lifecycle:lifecycle-runtime-ktx:$lifecycleVersion"
     implementation "androidx.lifecycle:lifecycle-service:$lifecycleVersion"
     implementation "androidx.webkit:webkit:$webkitVersion"
 
     implementation "com.android.volley:volley:$volleyVersion"
     implementation "com.squareup.wire:wire-runtime:$wireVersion"
+
+    implementation platform('androidx.compose:compose-bom:2024.04.00')
+    implementation 'androidx.compose.material3:material3'
+    implementation 'androidx.compose.ui:ui'
+    implementation 'androidx.activity:activity-compose:1.8.2'
+
 }
 
 wire {
@@ -39,6 +47,14 @@ android {
     compileSdkVersion androidCompileSdk
     buildToolsVersion "$androidBuildVersionTools"
 
+    buildFeatures {
+        compose true
+    }
+
+    composeOptions {
+        kotlinCompilerExtensionVersion = "1.5.10"
+    }
+
     defaultConfig {
         versionName version
         minSdkVersion androidMinSdk
@@ -51,6 +67,7 @@ android {
 
     lintOptions {
         disable 'MissingTranslation'
+        disable 'CoroutineCreationDuringComposition'
     }
 
     compileOptions {

play-services-recaptcha/core/src/main/AndroidManifest.xml

@@ -1,5 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
+<?xml version="1.0" encoding="utf-8"?><!--
   ~ SPDX-FileCopyrightText: 2021 microG Project Team
   ~ SPDX-License-Identifier: Apache-2.0
   -->
@@ -8,11 +7,34 @@
 
     <application>
         <!-- This service is in :ui process because it may spawn a web view. See https://crbug.com/558377 -->
-        <service android:name="org.microg.gms.recaptcha.RecaptchaService"
-                 android:process=":ui">
+        <service
+            android:name="org.microg.gms.recaptcha.RecaptchaService"
+            android:process=":ui">
             <intent-filter>
-                <action android:name="com.google.android.gms.recaptcha.service.START"/>
+                <action android:name="com.google.android.gms.recaptcha.service.START" />
             </intent-filter>
         </service>
+
+        <activity
+            android:name="org.microg.gms.recaptcha.RecaptchaDeepLinkActivity"
+            android:configChanges="orientation|screenSize"
+            android:enabled="true"
+            android:excludeFromRecents="true"
+            android:exported="true"
+            android:launchMode="singleTask"
+            android:taskAffinity=""
+            android:theme="@style/Theme.AppCompat.DayNight.NoActionBar">
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+
+                <category android:name="android.intent.category.BROWSABLE" />
+                <category android:name="android.intent.category.DEFAULT" />
+
+                <data android:scheme="https" />
+                <data android:host="recaptcha.net" />
+                <data android:host="recaptcha.google.com" />
+                <data android:pathPrefix="/qr" />
+            </intent-filter>
+        </activity>
     </application>
 </manifest>

play-services-recaptcha/core/src/main/kotlin/org/microg/gms/recaptcha/RecaptchaDeepLinkActivity.kt

@@ -0,0 +1,114 @@
+/*
+ * SPDX-FileCopyrightText: 2026 microG Project Team
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.microg.gms.recaptcha
+
+import android.content.Intent
+import android.net.Uri
+import android.os.Bundle
+import android.util.Log
+import androidx.activity.compose.setContent
+import androidx.appcompat.app.AppCompatActivity
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.lifecycle.lifecycleScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import org.microg.gms.profile.ProfileManager
+import org.microg.gms.recaptcha.modac.RecaptchaQrVerifier
+import org.microg.gms.recaptcha.modac.VerificationOutcome
+
+private const val TAG = "RecaptchaDeepLink"
+private const val QR_TOKEN_SEPARATOR = "/qr/"
+private const val MAX_QR_TOKEN_LENGTH = 4096
+private val ALLOWED_HOSTS = setOf("recaptcha.net", "recaptcha.google.com")
+
+class RecaptchaDeepLinkActivity : AppCompatActivity() {
+
+    private var status by mutableStateOf(VerificationStatus.CONFIRM)
+    private var qrToken: String? = null
+    private var verificationJob: Job? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        ProfileManager.ensureInitialized(this)
+        RecaptchaQrVerifier.init(this, signalUpdateScope = lifecycleScope)
+        if (!acceptDeepLink(intent)) {
+            finish()
+            return
+        }
+        setContent {
+            RecaptchaDeepLinkScreen(
+                status = status,
+                onPrimaryButtonClick = { onPrimaryButtonClick(status) },
+                onSecondaryButtonClick = ::finish,
+            )
+        }
+    }
+
+    override fun onNewIntent(intent: Intent) {
+        super.onNewIntent(intent)
+        setIntent(intent)
+        verificationJob?.cancel()
+        verificationJob = null
+        qrToken = null
+        if (!acceptDeepLink(intent)) finish()
+    }
+
+    private fun acceptDeepLink(intent: Intent?): Boolean {
+        val data = intent?.data
+        val token = data?.let(::extractQrToken)
+        if (intent?.action != Intent.ACTION_VIEW || data == null || data.scheme != "https" ||
+            ALLOWED_HOSTS.none { it.equals(data.host, ignoreCase = true) } || token == null
+        ) {
+            Log.d(TAG, "Rejecting invalid reCAPTCHA QR deep link")
+            return false
+        }
+        qrToken = token
+        status = VerificationStatus.CONFIRM
+        return true
+    }
+
+    private fun onPrimaryButtonClick(status: VerificationStatus) {
+        when (status) {
+            VerificationStatus.CONFIRM -> startVerification()
+            VerificationStatus.LOADING,
+            VerificationStatus.FAILED,
+            VerificationStatus.VERIFIED -> finish()
+        }
+    }
+
+    private fun startVerification() {
+        val token = qrToken
+        if (token == null) {
+            Log.d(TAG, "Verification requested without an accepted token")
+            finish()
+            return
+        }
+        qrToken = null
+        status = VerificationStatus.LOADING
+        verificationJob?.cancel()
+        verificationJob = lifecycleScope.launch {
+            val outcome = withContext(Dispatchers.IO) {
+                RecaptchaQrVerifier.verifyToken(token)
+            }
+            status = when (outcome) {
+                VerificationOutcome.Verified -> VerificationStatus.VERIFIED
+                is VerificationOutcome.Failed -> VerificationStatus.FAILED
+            }
+        }
+    }
+
+    private fun extractQrToken(uri: Uri): String? {
+        if (!isAllowedPath(uri.path)) return null
+        val token = uri.pathSegments.drop(1).joinToString("/")
+        return token.takeIf { it.isNotEmpty() && it.length <= MAX_QR_TOKEN_LENGTH }
+    }
+
+    private fun isAllowedPath(path: String?): Boolean = path?.startsWith(QR_TOKEN_SEPARATOR) == true
+}

play-services-recaptcha/core/src/main/kotlin/org/microg/gms/recaptcha/RecaptchaDeepLinkScreen.kt

@@ -0,0 +1,156 @@
+/*
+ * SPDX-FileCopyrightText: 2026 microG Project Team
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.microg.gms.recaptcha
+
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import org.microg.gms.recaptcha.core.R
+
+private val FilledButtonColor = Color(0xFF1A73E8)
+private val LinkButtonColor = Color(0xFF1967D2)
+
+internal enum class VerificationStatus {
+    CONFIRM,
+    LOADING,
+    FAILED,
+    VERIFIED,
+}
+
+private fun VerificationStatus.titleRes(): Int = when (this) {
+    VerificationStatus.CONFIRM -> R.string.recaptcha_qr_confirm_title
+    VerificationStatus.LOADING -> R.string.recaptcha_qr_progress_title
+    VerificationStatus.FAILED -> R.string.recaptcha_qr_failed_title
+    VerificationStatus.VERIFIED -> R.string.recaptcha_qr_success_title
+}
+
+private fun VerificationStatus.descriptionRes(): Int = when (this) {
+    VerificationStatus.CONFIRM -> R.string.recaptcha_qr_confirm_description
+    VerificationStatus.LOADING -> R.string.recaptcha_qr_progress_description
+    VerificationStatus.FAILED -> R.string.recaptcha_qr_failed_description
+    VerificationStatus.VERIFIED -> R.string.recaptcha_qr_success_description
+}
+
+private fun VerificationStatus.primaryButtonRes(): Int = when (this) {
+    VerificationStatus.CONFIRM -> R.string.recaptcha_qr_confirm_button
+    VerificationStatus.LOADING -> R.string.recaptcha_qr_progress_button
+    VerificationStatus.FAILED -> R.string.recaptcha_qr_failed_button
+    VerificationStatus.VERIFIED -> R.string.recaptcha_qr_success_button
+}
+
+private fun VerificationStatus.illustrationRes(): Int = when (this) {
+    VerificationStatus.CONFIRM -> R.drawable.ic_recaptcha_qr_confirm
+    VerificationStatus.LOADING -> R.drawable.ic_recaptcha_qr_progress
+    VerificationStatus.FAILED -> R.drawable.ic_recaptcha_qr_failed
+    VerificationStatus.VERIFIED -> R.drawable.ic_recaptcha_qr_success
+}
+
+@Composable
+internal fun RecaptchaDeepLinkScreen(
+    status: VerificationStatus,
+    onPrimaryButtonClick: () -> Unit,
+    onSecondaryButtonClick: () -> Unit,
+) {
+    Surface(modifier = Modifier.fillMaxSize()) {
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(24.dp),
+            horizontalAlignment = Alignment.CenterHorizontally,
+            verticalArrangement = Arrangement.Center,
+        ) {
+            Image(
+                painter = painterResource(status.illustrationRes()),
+                contentDescription = null,
+                modifier = Modifier.size(96.dp),
+            )
+            Spacer(Modifier.height(24.dp))
+            Text(
+                text = stringResource(status.titleRes()),
+                fontSize = 20.sp,
+                fontWeight = FontWeight.Medium,
+                textAlign = TextAlign.Center,
+                color = MaterialTheme.colorScheme.onSurface,
+            )
+            Spacer(Modifier.height(16.dp))
+            Text(
+                text = stringResource(status.descriptionRes()),
+                fontSize = 16.sp,
+                textAlign = TextAlign.Center,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+            Spacer(Modifier.height(32.dp))
+            PrimaryButton(status, onPrimaryButtonClick)
+            if (status == VerificationStatus.CONFIRM) {
+                TextButton(onClick = onSecondaryButtonClick) {
+                    Text(
+                        text = stringResource(R.string.recaptcha_qr_confirm_cancel_button),
+                        color = LinkButtonColor,
+                    )
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun PrimaryButton(status: VerificationStatus, onClick: () -> Unit) {
+    val label = stringResource(status.primaryButtonRes())
+    when (status) {
+        VerificationStatus.CONFIRM,
+        VerificationStatus.VERIFIED -> Button(
+            onClick = onClick,
+            modifier = Modifier.fillMaxWidth(),
+            colors = ButtonDefaults.buttonColors(containerColor = FilledButtonColor),
+        ) {
+            Text(label, color = Color.White)
+        }
+
+        VerificationStatus.FAILED -> OutlinedButton(
+            onClick = onClick,
+            modifier = Modifier.fillMaxWidth(),
+        ) {
+            Text(label, color = LinkButtonColor)
+        }
+
+        VerificationStatus.LOADING -> TextButton(
+            onClick = onClick,
+            modifier = Modifier.fillMaxWidth(),
+        ) {
+            CircularProgressIndicator(
+                modifier = Modifier.size(18.dp),
+                color = LinkButtonColor,
+                strokeWidth = 2.dp,
+            )
+            Spacer(Modifier.size(8.dp))
+            Text(label, color = LinkButtonColor)
+        }
+    }
+}