verity: Add tools to help OEMs generate signed boot images.
Change-Id: Iea200def2fdd8a0d366888bb7b1ae401297063f1
diff --git a/verity/Utils.java b/verity/Utils.java
new file mode 100644
index 0000000..2c1e7bb
--- /dev/null
+++ b/verity/Utils.java
@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.verity;
+
+import java.lang.reflect.Constructor;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+import java.security.KeyFactory;
+import java.security.Provider;
+import java.security.Security;
+import java.security.Signature;
+import java.security.spec.X509EncodedKeySpec;
+import java.security.spec.PKCS8EncodedKeySpec;
+
+import org.bouncycastle.util.encoders.Base64;
+
+public class Utils {
+
+ private static void loadProviderIfNecessary(String providerClassName) {
+ if (providerClassName == null) {
+ return;
+ }
+
+ final Class<?> klass;
+ try {
+ final ClassLoader sysLoader = ClassLoader.getSystemClassLoader();
+ if (sysLoader != null) {
+ klass = sysLoader.loadClass(providerClassName);
+ } else {
+ klass = Class.forName(providerClassName);
+ }
+ } catch (ClassNotFoundException e) {
+ e.printStackTrace();
+ System.exit(1);
+ return;
+ }
+
+ Constructor<?> constructor = null;
+ for (Constructor<?> c : klass.getConstructors()) {
+ if (c.getParameterTypes().length == 0) {
+ constructor = c;
+ break;
+ }
+ }
+ if (constructor == null) {
+ System.err.println("No zero-arg constructor found for " + providerClassName);
+ System.exit(1);
+ return;
+ }
+
+ final Object o;
+ try {
+ o = constructor.newInstance();
+ } catch (Exception e) {
+ e.printStackTrace();
+ System.exit(1);
+ return;
+ }
+ if (!(o instanceof Provider)) {
+ System.err.println("Not a Provider class: " + providerClassName);
+ System.exit(1);
+ }
+
+ Security.insertProviderAt((Provider) o, 1);
+ }
+
+ static byte[] pemToDer(String pem) throws Exception {
+ pem = pem.replaceAll("^-.*", "");
+ String base64_der = pem.replaceAll("-.*$", "");
+ return Base64.decode(base64_der);
+ }
+
+ static PrivateKey loadDERPrivateKey(byte[] der) throws Exception {
+ PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(der);
+ KeyFactory keyFactory = KeyFactory.getInstance("RSA");
+ return (PrivateKey) keyFactory.generatePrivate(keySpec);
+ }
+
+ static PrivateKey loadPEMPrivateKey(byte[] pem) throws Exception {
+ byte[] der = pemToDer(new String(pem));
+ return loadDERPrivateKey(der);
+ }
+
+ static PrivateKey loadPEMPrivateKeyFromFile(String keyFname) throws Exception {
+ return loadPEMPrivateKey(read(keyFname));
+ }
+
+ static PrivateKey loadDERPrivateKeyFromFile(String keyFname) throws Exception {
+ return loadDERPrivateKey(read(keyFname));
+ }
+
+ static PublicKey loadDERPublicKey(byte[] der) throws Exception {
+ X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(der);
+ KeyFactory factory = KeyFactory.getInstance("RSA");
+ return factory.generatePublic(publicKeySpec);
+ }
+
+ static PublicKey loadPEMPublicKey(byte[] pem) throws Exception {
+ byte[] der = pemToDer(new String(pem));
+ X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(der);
+ KeyFactory factory = KeyFactory.getInstance("RSA");
+ return factory.generatePublic(publicKeySpec);
+ }
+
+ static PublicKey loadPEMPublicKeyFromFile(String keyFname) throws Exception {
+ return loadPEMPublicKey(read(keyFname));
+ }
+
+ static PublicKey loadDERPublicKeyFromFile(String keyFname) throws Exception {
+ return loadDERPublicKey(read(keyFname));
+ }
+
+ static byte[] sign(PrivateKey privateKey, byte[] input) throws Exception {
+ Signature signer = Signature.getInstance("SHA1withRSA");
+ signer.initSign(privateKey);
+ signer.update(input);
+ return signer.sign();
+ }
+
+ static byte[] read(String fname) throws Exception {
+ long offset = 0;
+ File f = new File(fname);
+ long length = f.length();
+ byte[] image = new byte[(int)length];
+ FileInputStream fis = new FileInputStream(f);
+ while (offset < length) {
+ offset += fis.read(image, (int)offset, (int)(length - offset));
+ }
+ fis.close();
+ return image;
+ }
+
+ static void write(byte[] data, String fname) throws Exception{
+ FileOutputStream out = new FileOutputStream(fname);
+ out.write(data);
+ out.close();
+ }
+}
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