| /* |
| * Copyright (C) 2009 Google Inc. All rights reserved. |
| * |
| * 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.google.polo.pairing; |
| |
| import com.google.polo.exception.PoloException; |
| |
| import java.math.BigInteger; |
| import java.security.cert.Certificate; |
| |
| import javax.net.ssl.SSLPeerUnverifiedException; |
| import javax.net.ssl.SSLSession; |
| |
| /** |
| * Utility methods of general usefulness to the Polo library. |
| */ |
| public class PoloUtil { |
| |
| /** |
| * Returns the peer {@link Certificate} for an {@link SSLSession}. |
| * |
| * @throws PoloException if the peer certificate could not be obtained |
| * from the {@link SSLSession}. |
| * @return the {@link Certificate} of the peer |
| */ |
| public static Certificate getPeerCert(SSLSession session) |
| throws PoloException { |
| try { |
| // Peer certificate |
| Certificate[] certs = session.getPeerCertificates(); |
| if (certs == null || certs.length < 1) { |
| throw new PoloException("No peer certificate."); |
| } |
| return certs[0]; |
| } catch (SSLPeerUnverifiedException e) { |
| throw new PoloException(e); |
| } |
| } |
| |
| /** |
| * Return the local {@link Certificate} for an {@link SSLSession}. |
| * |
| * @throws PoloException if the local certificate could not be obtained |
| * from the {@link SSLSession} |
| * @return the {@link Certificate} of the peer |
| */ |
| public static Certificate getLocalCert(SSLSession session) |
| throws PoloException { |
| Certificate[] certs = session.getLocalCertificates(); |
| if (certs == null || certs.length < 1) { |
| throw new PoloException("No local certificate."); |
| } |
| return certs[0]; |
| } |
| |
| /** |
| * Converts an array of bytes to a string of hexadecimal characters. |
| * Leading null bytes are preserved in the output. |
| * <p> |
| * The input byte stream is assumed to be a positive, two's complement |
| * representation of an integer. The return value is the hexadecimal string |
| * representation of this value. |
| * |
| * @param bytes the bytes to convert |
| * @return the string representation |
| */ |
| public static String bytesToHexString(byte[] bytes) { |
| if (bytes == null || bytes.length == 0) { |
| return ""; |
| } |
| BigInteger bigint = new BigInteger(1, bytes); |
| int formatLen = bytes.length * 2; |
| return String.format("%0" + formatLen + "x", bigint); |
| } |
| |
| /** |
| * Converts a string of hex characters to a byte array. |
| * |
| * @param hexstr the string of hex characters |
| * @return a byte array representation |
| */ |
| public static byte[] hexStringToBytes(String hexstr) { |
| if (hexstr == null || hexstr.length() == 0 || (hexstr.length() % 2) != 0) { |
| throw new IllegalArgumentException("Bad input string."); |
| } |
| |
| byte[] result = new byte[hexstr.length() / 2]; |
| for (int i=0; i < result.length; i++) { |
| result[i] = (byte) Integer.parseInt(hexstr.substring(2 * i, 2 * (i + 1)), |
| 16); |
| } |
| return result; |
| } |
| |
| /** |
| * Converts an integer value to the big endian 4-byte representation. |
| */ |
| public static final byte[] intToBigEndianIntBytes(int intVal) { |
| byte[] outBuf = new byte[4]; |
| outBuf[0] = (byte)((intVal >> 24) & 0xff); |
| outBuf[1] = (byte)((intVal >> 16) & 0xff); |
| outBuf[2] = (byte)((intVal >> 8) & 0xff); |
| outBuf[3] = (byte)(intVal & 0xff); |
| return outBuf; |
| } |
| |
| /** |
| * Converts a 4-byte array of bytes to an unsigned long value. |
| */ |
| public static final long intBigEndianBytesToLong(byte[] input) { |
| assert (input.length == 4); |
| long ret = (long)(input[0]) & 0xff; |
| ret <<= 8; |
| ret |= (long)(input[1]) & 0xff; |
| ret <<= 8; |
| ret |= (long)(input[2]) & 0xff; |
| ret <<= 8; |
| ret |= (long)(input[3]) & 0xff; |
| return ret; |
| } |
| |
| } |