Fix signatures are being deprecated

mobile/src/main/java/com/github/shadowsocks/App.kt

@@ -34,6 +34,7 @@ import android.os.Build
 import android.os.Handler
 import android.os.Looper
 import android.support.annotation.RequiresApi
+import android.support.v4.os.BuildCompat
 import android.support.v4.os.UserManagerCompat
 import android.support.v7.app.AppCompatDelegate
 import android.util.Log
@@ -73,8 +74,8 @@ class App : Application() {
     private val tracker: Tracker by lazy { GoogleAnalytics.getInstance(deviceContext).newTracker(R.xml.tracker) }
     val info: PackageInfo by lazy { getPackageInfo(packageName) }
 
-    fun getPackageInfo(packageName: String) =
-            packageManager.getPackageInfo(packageName, PackageManager.GET_SIGNATURES)!!
+    fun getPackageInfo(packageName: String) = packageManager.getPackageInfo(packageName, if (BuildCompat.isAtLeastP())
+        PackageManager.GET_SIGNING_CERTIFICATES else @Suppress("DEPRECATION") PackageManager.GET_SIGNATURES)!!
 
     fun startService() {
         val intent = Intent(this, BaseService.serviceClass.java)

mobile/src/main/java/com/github/shadowsocks/bg/BaseService.kt

@@ -354,7 +354,7 @@ object BaseService {
                                 .readTimeout(30, TimeUnit.SECONDS)
                                 .build()
                         val mdg = MessageDigest.getInstance("SHA-1")
-                        mdg.update(app.info.signatures[0].toByteArray())
+                        mdg.update(app.info.signaturesCompat.first().toByteArray())
                         val requestBody = FormBody.Builder()
                                 .add("sig", String(Base64.encode(mdg.digest(), 0)))
                                 .build()

mobile/src/main/java/com/github/shadowsocks/plugin/PluginManager.kt

@@ -32,6 +32,7 @@ import android.util.Base64
 import android.util.Log
 import com.github.shadowsocks.App.Companion.app
 import com.github.shadowsocks.utils.Commandline
+import com.github.shadowsocks.utils.signaturesCompat
 import eu.chainfire.libsuperuser.Shell
 import java.io.File
 import java.io.FileNotFoundException
@@ -47,7 +48,7 @@ object PluginManager {
      * public key yet since it will also automatically trust packages signed by the same signatures, e.g. debug keys.
      */
     val trustedSignatures by lazy {
-        app.info.signatures.toSet() +
+        app.info.signaturesCompat.toSet() +
                 Signature(Base64.decode(  // @Mygod
                 """
                     |MIIDWzCCAkOgAwIBAgIEUzfv8DANBgkqhkiG9w0BAQsFADBdMQswCQYDVQQGEwJD

mobile/src/main/java/com/github/shadowsocks/plugin/ResolvedPlugin.kt

@@ -24,6 +24,7 @@ import android.content.pm.ResolveInfo
 import android.graphics.drawable.Drawable
 import android.os.Bundle
 import com.github.shadowsocks.App.Companion.app
+import com.github.shadowsocks.utils.signaturesCompat
 
 abstract class ResolvedPlugin(protected val resolveInfo: ResolveInfo) : Plugin() {
     protected abstract val metaData: Bundle
@@ -34,6 +35,6 @@ abstract class ResolvedPlugin(protected val resolveInfo: ResolveInfo) : Plugin()
     override val defaultConfig: String by lazy { metaData.getString(PluginContract.METADATA_KEY_DEFAULT_CONFIG) }
     override val packageName: String get() = resolveInfo.resolvePackageName
     override val trusted by lazy {
-        app.getPackageInfo(packageName).signatures.any(PluginManager.trustedSignatures::contains)
+        app.getPackageInfo(packageName).signaturesCompat.any(PluginManager.trustedSignatures::contains)
     }
 }

mobile/src/main/java/com/github/shadowsocks/utils/Utils.kt

@@ -3,12 +3,14 @@ package com.github.shadowsocks.utils
 import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
+import android.content.pm.PackageInfo
 import android.content.res.Resources
 import android.os.Build
 import android.support.annotation.AttrRes
 import android.support.v4.app.Fragment
 import android.support.v4.app.FragmentManager
 import android.support.v4.content.ContextCompat
+import android.support.v4.os.BuildCompat
 import android.support.v7.util.SortedList
 import android.util.TypedValue
 import com.github.shadowsocks.App.Companion.app
@@ -53,6 +55,10 @@ val URLConnection.responseLength: Long
 
 inline fun <reified T> Context.systemService() = ContextCompat.getSystemService(this, T::class.java)!!
 
+val PackageInfo.signaturesCompat get() =
+    if (BuildCompat.isAtLeastP()) signingCertificateHistory.flatten()
+    else @Suppress("DEPRECATION") signatures.asIterable()
+
 /**
  * Based on: https://stackoverflow.com/a/15656428/2245107
  */