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Commit df0db7fe authored by Ben Gruver's avatar Ben Gruver Committed by Android (Google) Code Review
Browse files

Merge "Don't verify signatures in ConfigUpdateInstallReceiver"

parents fcfff284 12964bf5

core/res/AndroidManifest.xml

+20 −6
Original line number Diff line number Diff line
@@ -1636,6 +1636,14 @@ 
        android:protectionLevel="signature" />

    <uses-permission android:name="android.permission.BIND_JOB_SERVICE"/>



    <!-- Allows an application to initiate configuration updates

         <p>An application requesting this permission is responsible for

         verifying the source and integrity of any update before passing

         it off to the various individual installer components

         @hide -->

    <permission android:name="android.permission.UPDATE_CONFIG"

        android:protectionLevel="signature|system" />



    <!-- ========================================= -->

    <!-- Permissions for special development tools -->

    <!-- ========================================= -->
@@ -2556,42 +2564,48 @@ 
            </intent-filter>

        </receiver>



        <receiver android:name="com.android.server.updates.CertPinInstallReceiver" >

        <receiver android:name="com.android.server.updates.CertPinInstallReceiver"

                android:permission="android.permission.UPDATE_CONFIG">

            <intent-filter>

                <action android:name="android.intent.action.UPDATE_PINS" />

                <data android:scheme="content" android:host="*" android:mimeType="*/*" />

            </intent-filter>

        </receiver>



        <receiver android:name="com.android.server.updates.IntentFirewallInstallReceiver" >

        <receiver android:name="com.android.server.updates.IntentFirewallInstallReceiver"

                android:permission="android.permission.UPDATE_CONFIG">

            <intent-filter>

                <action android:name="android.intent.action.UPDATE_INTENT_FIREWALL" />

                <data android:scheme="content" android:host="*" android:mimeType="*/*" />

            </intent-filter>

        </receiver>



        <receiver android:name="com.android.server.updates.SmsShortCodesInstallReceiver" >

        <receiver android:name="com.android.server.updates.SmsShortCodesInstallReceiver"

                android:permission="android.permission.UPDATE_CONFIG">

            <intent-filter>

                <action android:name="android.intent.action.UPDATE_SMS_SHORT_CODES" />

                <data android:scheme="content" android:host="*" android:mimeType="*/*" />

            </intent-filter>

        </receiver>



        <receiver android:name="com.android.server.updates.CarrierProvisioningUrlsInstallReceiver" >

        <receiver android:name="com.android.server.updates.CarrierProvisioningUrlsInstallReceiver"

                android:permission="android.permission.UPDATE_CONFIG">

            <intent-filter>

                <action android:name="android.intent.action.UPDATE_CARRIER_PROVISIONING_URLS" />

                <data android:scheme="content" android:host="*" android:mimeType="*/*" />

            </intent-filter>

        </receiver>



        <receiver android:name="com.android.server.updates.TzDataInstallReceiver" >

        <receiver android:name="com.android.server.updates.TzDataInstallReceiver"

                android:permission="android.permission.UPDATE_CONFIG">

            <intent-filter>

                <action android:name="android.intent.action.UPDATE_TZDATA" />

                <data android:scheme="content" android:host="*" android:mimeType="*/*" />

            </intent-filter>

        </receiver>



        <receiver android:name="com.android.server.updates.SELinuxPolicyInstallReceiver" >

        <receiver android:name="com.android.server.updates.SELinuxPolicyInstallReceiver"

                android:permission="android.permission.UPDATE_CONFIG">

            <intent-filter>

                <action android:name="android.intent.action.UPDATE_SEPOLICY" />

                <data android:scheme="content" android:host="*" android:mimeType="*/*" />

services/core/java/com/android/server/updates/ConfigUpdateInstallReceiver.java

+3 −54
Original line number Diff line number Diff line
@@ -16,29 +16,21 @@ 


package com.android.server.updates;



import com.android.server.EventLogTags;



import android.content.BroadcastReceiver;

import android.content.ContentResolver;

import android.content.Context;

import android.content.Intent;

import android.net.Uri;

import android.provider.Settings;

import android.util.Base64;

import android.util.EventLog;

import android.util.Slog;



import com.android.server.EventLogTags;



import java.io.ByteArrayInputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.InputStream;

import java.io.IOException;

import java.security.cert.CertificateException;

import java.security.cert.CertificateFactory;

import java.security.cert.X509Certificate;

import java.io.InputStream;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import java.security.Signature;



import libcore.io.IoUtils;

import libcore.io.Streams;
@@ -48,11 +40,8 @@ public class ConfigUpdateInstallReceiver extends BroadcastReceiver { 
    private static final String TAG = "ConfigUpdateInstallReceiver";



    private static final String EXTRA_REQUIRED_HASH = "REQUIRED_HASH";

    private static final String EXTRA_SIGNATURE = "SIGNATURE";

    private static final String EXTRA_VERSION_NUMBER = "VERSION";



    private static final String UPDATE_CERTIFICATE_KEY = "config_update_certificate";



    protected final File updateDir;

    protected final File updateContent;

    protected final File updateVersion;
@@ -71,16 +60,12 @@ public class ConfigUpdateInstallReceiver extends BroadcastReceiver { 
            @Override

            public void run() {

                try {

                    // get the certificate from Settings.Secure

                    X509Certificate cert = getCert(context.getContentResolver());

                    // get the content path from the extras

                    byte[] altContent = getAltContent(context, intent);

                    // get the version from the extras

                    int altVersion = getVersionFromIntent(intent);

                    // get the previous value from the extras

                    String altRequiredHash = getRequiredHashFromIntent(intent);

                    // get the signature from the extras

                    String altSig = getSignatureFromIntent(intent);

                    // get the version currently being used

                    int currentVersion = getCurrentVersion();

                    // get the hash of the currently used value
@@ -90,10 +75,6 @@ public class ConfigUpdateInstallReceiver extends BroadcastReceiver { 
                    } else if (!verifyPreviousHash(currentHash, altRequiredHash)) {

                        EventLog.writeEvent(EventLogTags.CONFIG_INSTALL_FAILED,

                                            "Current hash did not match required value");

                    } else if (!verifySignature(altContent, altVersion, altRequiredHash, altSig,

                               cert)) {

                        EventLog.writeEvent(EventLogTags.CONFIG_INSTALL_FAILED,

                                            "Signature did not verify");

                    } else {

                        // install the new content

                        Slog.i(TAG, "Found new update, installing...");
@@ -114,20 +95,6 @@ public class ConfigUpdateInstallReceiver extends BroadcastReceiver { 
        }.start();

    }



    private X509Certificate getCert(ContentResolver cr) {

        // get the cert from settings

        String cert = Settings.Secure.getString(cr, UPDATE_CERTIFICATE_KEY);

        // convert it into a real certificate

        try {

            byte[] derCert = Base64.decode(cert.getBytes(), Base64.DEFAULT);

            InputStream istream = new ByteArrayInputStream(derCert);

            CertificateFactory cf = CertificateFactory.getInstance("X.509");

            return (X509Certificate) cf.generateCertificate(istream);

        } catch (CertificateException e) {

            throw new IllegalStateException("Got malformed certificate from settings, ignoring");

        }

    }



    private Uri getContentFromIntent(Intent i) {

        Uri data = i.getData();

        if (data == null) {
@@ -152,14 +119,6 @@ public class ConfigUpdateInstallReceiver extends BroadcastReceiver { 
        return extraValue.trim();

    }



    private String getSignatureFromIntent(Intent i) {

        String extraValue = i.getStringExtra(EXTRA_SIGNATURE);

        if (extraValue == null) {

            throw new IllegalStateException("Missing required signature, ignoring.");

        }

        return extraValue.trim();

    }



    private int getCurrentVersion() throws NumberFormatException {

        try {

            String strVersion = IoUtils.readFileAsString(updateVersion.getCanonicalPath()).trim();
@@ -215,16 +174,6 @@ public class ConfigUpdateInstallReceiver extends BroadcastReceiver { 
        return current.equals(required);

    }



    private boolean verifySignature(byte[] content, int version, String requiredPrevious,

                                   String signature, X509Certificate cert) throws Exception {

        Signature signer = Signature.getInstance("SHA512withRSA");

        signer.initVerify(cert);

        signer.update(content);

        signer.update(Long.toString(version).getBytes());

        signer.update(requiredPrevious.getBytes());

        return signer.verify(Base64.decode(signature.getBytes(), Base64.DEFAULT));

    }



    protected void writeUpdate(File dir, File file, byte[] content) throws IOException {

        FileOutputStream out = null;

        File tmp = null;