org.argeo.util/src/org/argeo/util/DigestUtils.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   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 package org.argeo.util;
  17
  18 import java.io.File;
  19 import java.io.FileInputStream;
  20 import java.io.IOException;
  21 import java.io.InputStream;
  22 import java.nio.ByteBuffer;
  23 import java.nio.channels.FileChannel;
  24 import java.nio.channels.FileChannel.MapMode;
  25 import java.nio.file.Files;
  26 import java.nio.file.Path;
  27 import java.security.MessageDigest;
  28 import java.security.NoSuchAlgorithmException;
  29
  30 /** Utilities around cryptographic digests */
  31 public class DigestUtils {
  32         public final static String MD5 = "MD5";
  33         public final static String SHA1 = "SHA1";
  34         public final static String SHA256 = "SHA-256";
  35         public final static String SHA512 = "SHA-512";
  36
  37         private static Boolean debug = false;
  38         // TODO: make it writable
  39         private final static Integer byteBufferCapacity = 100 * 1024;// 100 KB
  40
  41         public static byte[] sha1(byte[] bytes) {
  42                 try {
  43                         MessageDigest digest = MessageDigest.getInstance(SHA1);
  44                         digest.update(bytes);
  45                         byte[] checksum = digest.digest();
  46                         return checksum;
  47                 } catch (Exception e) {
  48                         throw new UtilsException("Cannot SHA1 digest", e);
  49                 }
  50         }
  51
  52         public static String digest(String algorithm, byte[] bytes) {
  53                 try {
  54                         MessageDigest digest = MessageDigest.getInstance(algorithm);
  55                         digest.update(bytes);
  56                         byte[] checksum = digest.digest();
  57                         String res = encodeHexString(checksum);
  58                         return res;
  59                 } catch (Exception e) {
  60                         throw new UtilsException("Cannot digest with algorithm " + algorithm, e);
  61                 }
  62         }
  63
  64         public static String digest(String algorithm, InputStream in) {
  65                 try {
  66                         MessageDigest digest = MessageDigest.getInstance(algorithm);
  67                         // ReadableByteChannel channel = Channels.newChannel(in);
  68                         // ByteBuffer bb = ByteBuffer.allocateDirect(byteBufferCapacity);
  69                         // while (channel.read(bb) > 0)
  70                         // digest.update(bb);
  71                         byte[] buffer = new byte[byteBufferCapacity];
  72                         int read = 0;
  73                         while ((read = in.read(buffer)) > 0) {
  74                                 digest.update(buffer, 0, read);
  75                         }
  76
  77                         byte[] checksum = digest.digest();
  78                         String res = encodeHexString(checksum);
  79                         return res;
  80                 } catch (Exception e) {
  81                         throw new UtilsException("Cannot digest with algorithm " + algorithm, e);
  82                 } finally {
  83                         StreamUtils.closeQuietly(in);
  84                 }
  85         }
  86
  87         public static String digest(String algorithm, File file) {
  88                 FileInputStream fis = null;
  89                 FileChannel fc = null;
  90                 try {
  91                         fis = new FileInputStream(file);
  92                         fc = fis.getChannel();
  93
  94                         // Get the file's size and then map it into memory
  95                         int sz = (int) fc.size();
  96                         ByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, sz);
  97                         return digest(algorithm, bb);
  98                 } catch (IOException e) {
  99                         throw new UtilsException("Cannot digest " + file + " with algorithm " + algorithm, e);
 100                 } finally {
 101                         StreamUtils.closeQuietly(fis);
 102                         if (fc.isOpen())
 103                                 try {
 104                                         fc.close();
 105                                 } catch (IOException e) {
 106                                         // silent
 107                                 }
 108                 }
 109         }
 110
 111         protected static String digest(String algorithm, ByteBuffer bb) {
 112                 long begin = System.currentTimeMillis();
 113                 try {
 114                         MessageDigest digest = MessageDigest.getInstance(algorithm);
 115                         digest.update(bb);
 116                         byte[] checksum = digest.digest();
 117                         String res = encodeHexString(checksum);
 118                         long end = System.currentTimeMillis();
 119                         if (debug)
 120                                 System.out.println((end - begin) + " ms / " + ((end - begin) / 1000) + " s");
 121                         return res;
 122                 } catch (NoSuchAlgorithmException e) {
 123                         throw new UtilsException("Cannot digest with algorithm " + algorithm, e);
 124                 }
 125         }
 126
 127         public static String sha1hex(Path path) {
 128                 return digest(SHA1, path, byteBufferCapacity);
 129         }
 130
 131         public static String digest(String algorithm, Path path, long bufferSize) {
 132                 byte[] digest = digestRaw(algorithm, path, bufferSize);
 133                 return encodeHexString(digest);
 134         }
 135
 136         public static byte[] digestRaw(String algorithm, Path file, long bufferSize) {
 137                 long begin = System.currentTimeMillis();
 138                 try {
 139                         MessageDigest md = MessageDigest.getInstance(algorithm);
 140                         FileChannel fc = FileChannel.open(file);
 141                         long fileSize = Files.size(file);
 142                         if (fileSize <= bufferSize) {
 143                                 ByteBuffer bb = fc.map(MapMode.READ_ONLY, 0, fileSize);
 144                                 md.update(bb);
 145                         } else {
 146                                 long lastCycle = (fileSize / bufferSize) - 1;
 147                                 long position = 0;
 148                                 for (int i = 0; i <= lastCycle; i++) {
 149                                         ByteBuffer bb;
 150                                         if (i != lastCycle) {
 151                                                 bb = fc.map(MapMode.READ_ONLY, position, bufferSize);
 152                                                 position = position + bufferSize;
 153                                         } else {
 154                                                 bb = fc.map(MapMode.READ_ONLY, position, fileSize - position);
 155                                                 position = fileSize;
 156                                         }
 157                                         md.update(bb);
 158                                 }
 159                         }
 160                         long end = System.currentTimeMillis();
 161                         if (debug)
 162                                 System.out.println((end - begin) + " ms / " + ((end - begin) / 1000) + " s");
 163                         return md.digest();
 164                 } catch (Exception e) {
 165                         throw new UtilsException("Cannot digest " + file + "  with algorithm " + algorithm, e);
 166                 }
 167         }
 168
 169         public static void main(String[] args) {
 170                 File file;
 171                 if (args.length > 0)
 172                         file = new File(args[0]);
 173                 else {
 174                         System.err.println("Usage: <file> [<algorithm>]" + " (see http://java.sun.com/j2se/1.5.0/"
 175                                         + "docs/guide/security/CryptoSpec.html#AppA)");
 176                         return;
 177                 }
 178
 179                 if (args.length > 1) {
 180                         String algorithm = args[1];
 181                         System.out.println(digest(algorithm, file));
 182                 } else {
 183                         String algorithm = "MD5";
 184                         System.out.println(algorithm + ": " + digest(algorithm, file));
 185                         algorithm = "SHA";
 186                         System.out.println(algorithm + ": " + digest(algorithm, file));
 187                         System.out.println(algorithm + ": " + sha1hex(file.toPath()));
 188                         algorithm = "SHA-256";
 189                         System.out.println(algorithm + ": " + digest(algorithm, file));
 190                         algorithm = "SHA-512";
 191                         System.out.println(algorithm + ": " + digest(algorithm, file));
 192                 }
 193         }
 194
 195         final private static char[] hexArray = "0123456789abcdef".toCharArray();
 196
 197         /**
 198          * From
 199          * http://stackoverflow.com/questions/9655181/how-to-convert-a-byte-array-to
 200          * -a-hex-string-in-java
 201          */
 202         public static String encodeHexString(byte[] bytes) {
 203                 char[] hexChars = new char[bytes.length * 2];
 204                 for (int j = 0; j < bytes.length; j++) {
 205                         int v = bytes[j] & 0xFF;
 206                         hexChars[j * 2] = hexArray[v >>> 4];
 207                         hexChars[j * 2 + 1] = hexArray[v & 0x0F];
 208                 }
 209                 return new String(hexChars);
 210         }
 211
 212 }