org.argeo.enterprise/src/org/argeo/osgi/useradmin/DigestUtils.java

   1 package org.argeo.osgi.useradmin;
   2
   3 import java.nio.ByteBuffer;
   4 import java.nio.CharBuffer;
   5 import java.nio.charset.StandardCharsets;
   6 import java.security.MessageDigest;
   7 import java.util.Arrays;
   8
   9 /** Utilities around digests, mostly those related to passwords. */
  10 class DigestUtils {
  11         static byte[] sha1(byte[] bytes) {
  12                 try {
  13                         MessageDigest digest = MessageDigest.getInstance("SHA1");
  14                         digest.update(bytes);
  15                         byte[] checksum = digest.digest();
  16                         return checksum;
  17                 } catch (Exception e) {
  18                         throw new UserDirectoryException("Cannot SHA1 digest", e);
  19                 }
  20         }
  21
  22         static char[] bytesToChars(Object obj) {
  23                 if (obj instanceof char[])
  24                         return (char[]) obj;
  25                 if (!(obj instanceof byte[]))
  26                         throw new IllegalArgumentException(obj.getClass() + " is not a byte array");
  27                 ByteBuffer fromBuffer = ByteBuffer.wrap((byte[]) obj);
  28                 CharBuffer toBuffer = StandardCharsets.UTF_8.decode(fromBuffer);
  29                 char[] res = Arrays.copyOfRange(toBuffer.array(), toBuffer.position(), toBuffer.limit());
  30                 // Arrays.fill(fromBuffer.array(), (byte) 0); // clear sensitive data
  31                 // Arrays.fill((byte[]) obj, (byte) 0); // clear sensitive data
  32                 // Arrays.fill(toBuffer.array(), '\u0000'); // clear sensitive data
  33                 return res;
  34         }
  35
  36         static byte[] charsToBytes(char[] chars) {
  37                 CharBuffer charBuffer = CharBuffer.wrap(chars);
  38                 ByteBuffer byteBuffer = StandardCharsets.UTF_8.encode(charBuffer);
  39                 byte[] bytes = Arrays.copyOfRange(byteBuffer.array(), byteBuffer.position(), byteBuffer.limit());
  40                 // Arrays.fill(charBuffer.array(), '\u0000'); // clear sensitive data
  41                 // Arrays.fill(byteBuffer.array(), (byte) 0); // clear sensitive data
  42                 return bytes;
  43         }
  44
  45         static String sha1str(String str) {
  46                 byte[] hash = sha1(str.getBytes(StandardCharsets.UTF_8));
  47                 return encodeHexString(hash);
  48         }
  49
  50         final private static char[] hexArray = "0123456789abcdef".toCharArray();
  51
  52         /**
  53          * From
  54          * http://stackoverflow.com/questions/9655181/how-to-convert-a-byte-array-to
  55          * -a-hex-string-in-java
  56          */
  57         public static String encodeHexString(byte[] bytes) {
  58                 char[] hexChars = new char[bytes.length * 2];
  59                 for (int j = 0; j < bytes.length; j++) {
  60                         int v = bytes[j] & 0xFF;
  61                         hexChars[j * 2] = hexArray[v >>> 4];
  62                         hexChars[j * 2 + 1] = hexArray[v & 0x0F];
  63                 }
  64                 return new String(hexChars);
  65         }
  66
  67         private DigestUtils() {
  68         }
  69 }