auto import from //depot/cupcake/@135843
diff --git a/libmincrypt/tools/DumpPublicKey.java b/libmincrypt/tools/DumpPublicKey.java
new file mode 100644
index 0000000..c9e7e4d
--- /dev/null
+++ b/libmincrypt/tools/DumpPublicKey.java
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2008 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.dumpkey;
+
+import java.io.FileInputStream;
+import java.math.BigInteger;
+import java.security.cert.CertificateFactory;
+import java.security.cert.Certificate;
+import java.security.KeyStore;
+import java.security.Key;
+import java.security.PublicKey;
+import java.security.interfaces.RSAPublicKey;
+import sun.misc.BASE64Encoder;
+
+/**
+ * Command line tool to extract RSA public keys from X.509 certificates
+ * and output source code with data initializers for the keys.
+ * @hide
+ */
+class DumpPublicKey {
+ /**
+ * @param key to perform sanity checks on
+ * @throws Exception if the key has the wrong size or public exponent
+ */
+ static void check(RSAPublicKey key) throws Exception {
+ BigInteger pubexp = key.getPublicExponent();
+ BigInteger modulus = key.getModulus();
+
+ if (!pubexp.equals(BigInteger.valueOf(3)))
+ throw new Exception("Public exponent should be 3 but is " +
+ pubexp.toString(10) + ".");
+
+ if (modulus.bitLength() != 2048)
+ throw new Exception("Modulus should be 2048 bits long but is " +
+ modulus.bitLength() + " bits.");
+ }
+
+ /**
+ * @param key to output
+ * @return a C initializer representing this public key.
+ */
+ static String print(RSAPublicKey key) throws Exception {
+ check(key);
+
+ BigInteger N = key.getModulus();
+
+ StringBuilder result = new StringBuilder();
+
+ int nwords = N.bitLength() / 32; // # of 32 bit integers in modulus
+
+ result.append("{");
+ result.append(nwords);
+
+ BigInteger B = BigInteger.valueOf(0x100000000L); // 2^32
+ BigInteger N0inv = B.subtract(N.modInverse(B)); // -1 / N[0] mod 2^32
+
+ result.append(",0x");
+ result.append(N0inv.toString(16));
+
+ BigInteger R = BigInteger.valueOf(2).pow(N.bitLength());
+ BigInteger RR = R.multiply(R).mod(N); // 2^4096 mod N
+
+ // Write out modulus as little endian array of integers.
+ result.append(",{");
+ for (int i = 0; i < nwords; ++i) {
+ int n = N.mod(B).intValue();
+ result.append(n);
+
+ if (i != nwords - 1) {
+ result.append(",");
+ }
+
+ N = N.divide(B);
+ }
+ result.append("}");
+
+ // Write R^2 as little endian array of integers.
+ result.append(",{");
+ for (int i = 0; i < nwords; ++i) {
+ int rr = RR.mod(B).intValue();
+ result.append(rr);
+
+ if (i != nwords - 1) {
+ result.append(",");
+ }
+
+ RR = RR.divide(B);
+ }
+ result.append("}");
+
+ result.append("}");
+ return result.toString();
+ }
+
+ public static void main(String[] args) {
+ if (args.length < 1) {
+ System.err.println("Usage: DumpPublicKey certfile ... > source.c");
+ System.exit(1);
+ }
+ try {
+ for (int i = 0; i < args.length; i++) {
+ FileInputStream input = new FileInputStream(args[i]);
+ CertificateFactory cf = CertificateFactory.getInstance("X.509");
+ Certificate cert = cf.generateCertificate(input);
+ RSAPublicKey key = (RSAPublicKey) (cert.getPublicKey());
+ check(key);
+ System.out.print(print(key));
+ System.out.println(i < args.length - 1 ? "," : "");
+ }
+ } catch (Exception e) {
+ e.printStackTrace();
+ System.exit(1);
+ }
+ System.exit(0);
+ }
+}