security/DigestUtils.java

   1 /*
   2  * Copyright (C) 2010 Mathieu Baudier <mbaudier@argeo.org>
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.argeo.util.security;
  18
  19 import java.io.File;
  20 import java.io.FileInputStream;
  21 import java.io.IOException;
  22 import java.io.InputStream;
  23 import java.nio.ByteBuffer;
  24 import java.nio.channels.FileChannel;
  25 import java.security.MessageDigest;
  26 import java.security.NoSuchAlgorithmException;
  27
  28 import org.argeo.ArgeoException;
  29 import org.argeo.StreamUtils;
  30
  31 /** Utilities around cryptographic digests */
  32 public class DigestUtils {
  33         private static Boolean debug = true;
  34         // TODO: make it writable
  35         private final static Integer byteBufferCapacity = 100 * 1024;// 100 KB
  36
  37         public static String digest(String algorithm, InputStream in) {
  38                 try {
  39                         MessageDigest digest = MessageDigest.getInstance(algorithm);
  40                         // ReadableByteChannel channel = Channels.newChannel(in);
  41                         // ByteBuffer bb = ByteBuffer.allocateDirect(byteBufferCapacity);
  42                         // while (channel.read(bb) > 0)
  43                         // digest.update(bb);
  44                         byte[] buffer = new byte[byteBufferCapacity];
  45                         int read = 0;
  46                         while ((read = in.read(buffer)) > 0) {
  47                                 digest.update(buffer, 0, read);
  48                         }
  49
  50                         byte[] checksum = digest.digest();
  51                         String res = StreamUtils.encodeHexString(checksum);
  52                         return res;
  53                 } catch (Exception e) {
  54                         throw new ArgeoException("Cannot digest with algorithm "
  55                                         + algorithm, e);
  56                 } finally {
  57                         StreamUtils.closeQuietly(in);
  58                 }
  59         }
  60
  61         public static String digest(String algorithm, File file) {
  62                 FileInputStream fis = null;
  63                 FileChannel fc = null;
  64                 try {
  65                         fis = new FileInputStream(file);
  66                         fc = fis.getChannel();
  67
  68                         // Get the file's size and then map it into memory
  69                         int sz = (int) fc.size();
  70                         ByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, sz);
  71                         return digest(algorithm, bb);
  72                 } catch (IOException e) {
  73                         throw new ArgeoException("Cannot digest " + file
  74                                         + " with algorithm " + algorithm, e);
  75                 } finally {
  76                         StreamUtils.closeQuietly(fis);
  77                         if (fc.isOpen())
  78                                 try {
  79                                         fc.close();
  80                                 } catch (IOException e) {
  81                                         // silent
  82                                 }
  83                 }
  84         }
  85
  86         protected static String digest(String algorithm, ByteBuffer bb) {
  87                 long begin = System.currentTimeMillis();
  88                 try {
  89                         MessageDigest digest = MessageDigest.getInstance(algorithm);
  90                         digest.update(bb);
  91                         byte[] checksum = digest.digest();
  92                         String res = StreamUtils.encodeHexString(checksum);
  93                         long end = System.currentTimeMillis();
  94                         if (debug)
  95                                 System.out.println((end - begin) + " ms / "
  96                                                 + ((end - begin) / 1000) + " s");
  97                         return res;
  98                 } catch (NoSuchAlgorithmException e) {
  99                         throw new ArgeoException("Cannot digest with algorithm "
 100                                         + algorithm, e);
 101                 }
 102         }
 103
 104         public static void main(String[] args) {
 105                 File file;
 106                 if (args.length > 0)
 107                         file = new File(args[0]);
 108                 else {
 109                         System.err.println("Usage: <file> [<algorithm>]"
 110                                         + " (see http://java.sun.com/j2se/1.5.0/"
 111                                         + "docs/guide/security/CryptoSpec.html#AppA)");
 112                         return;
 113                 }
 114
 115                 if (args.length > 1) {
 116                         String algorithm = args[1];
 117                         System.out.println(digest(algorithm, file));
 118                 } else {
 119                         String algorithm = "MD5";
 120                         System.out.println(algorithm + ": " + digest(algorithm, file));
 121                         algorithm = "SHA";
 122                         System.out.println(algorithm + ": " + digest(algorithm, file));
 123                         algorithm = "SHA-256";
 124                         System.out.println(algorithm + ": " + digest(algorithm, file));
 125                         algorithm = "SHA-512";
 126                         System.out.println(algorithm + ": " + digest(algorithm, file));
 127                 }
 128         }
 129
 130 }