1 files changed, 145 insertions, 0 deletions
diff --git a/src/org/xbill/DNS/utils/base64.java b/src/org/xbill/DNS/utils/base64.java
new file mode 100644
index 0000000..54567cf
--- /dev/null
+++ b/src/org/xbill/DNS/utils/base64.java
@@ -0,0 +1,145 @@
+// Copyright (c) 1999-2004 Brian Wellington (bwelling@xbill.org)
+
+package org.xbill.DNS.utils;
+
+import java.io.*;
+
+/**
+ * Routines for converting between Strings of base64-encoded data and arrays of
+ * binary data.
+ *
+ * @author Brian Wellington
+ */
+
+public class base64 {
+
+private static final String Base64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
+
+private
+base64() {}
+
+/**
+ * Convert binary data to a base64-encoded String
+ * @param b An array containing binary data
+ * @return A String containing the encoded data
+ */
+public static String
+toString(byte [] b) {
+	ByteArrayOutputStream os = new ByteArrayOutputStream();
+
+	for (int i = 0; i < (b.length + 2) / 3; i++) {
+		short [] s = new short[3];
+		short [] t = new short[4];
+		for (int j = 0; j < 3; j++) {
+			if ((i * 3 + j) < b.length)
+				s[j] = (short) (b[i*3+j] & 0xFF);
+			else
+				s[j] = -1;
+		}
+		
+		t[0] = (short) (s[0] >> 2);
+		if (s[1] == -1)
+			t[1] = (short) (((s[0] & 0x3) << 4));
+		else
+			t[1] = (short) (((s[0] & 0x3) << 4) + (s[1] >> 4));
+		if (s[1] == -1)
+			t[2] = t[3] = 64;
+		else if (s[2] == -1) {
+			t[2] = (short) (((s[1] & 0xF) << 2));
+			t[3] = 64;
+		}
+		else {
+			t[2] = (short) (((s[1] & 0xF) << 2) + (s[2] >> 6));
+			t[3] = (short) (s[2] & 0x3F);
+		}
+		for (int j = 0; j < 4; j++)
+			os.write(Base64.charAt(t[j]));
+	}
+	return new String(os.toByteArray());
+}
+
+/**
+ * Formats data into a nicely formatted base64 encoded String
+ * @param b An array containing binary data
+ * @param lineLength The number of characters per line
+ * @param prefix A string prefixing the characters on each line
+ * @param addClose Whether to add a close parenthesis or not
+ * @return A String representing the formatted output
+ */
+public static String
+formatString(byte [] b, int lineLength, String prefix, boolean addClose) {
+	String s = toString(b);
+	StringBuffer sb = new StringBuffer();
+	for (int i = 0; i < s.length(); i += lineLength) {
+		sb.append (prefix);
+		if (i + lineLength >= s.length()) {
+			sb.append(s.substring(i));
+			if (addClose)
+				sb.append(" )");
+		}
+		else {
+			sb.append(s.substring(i, i + lineLength));
+			sb.append("\n");
+		}
+	}
+	return sb.toString();
+}
+
+
+/**
+ * Convert a base64-encoded String to binary data
+ * @param str A String containing the encoded data
+ * @return An array containing the binary data, or null if the string is invalid
+ */
+public static byte []
+fromString(String str) {
+	ByteArrayOutputStream bs = new ByteArrayOutputStream();
+	byte [] raw = str.getBytes();
+	for (int i = 0; i < raw.length; i++) {
+		if (!Character.isWhitespace((char)raw[i]))
+			bs.write(raw[i]);
+	}
+	byte [] in = bs.toByteArray();
+	if (in.length % 4 != 0) {
+		return null;
+	}
+
+	bs.reset();
+	DataOutputStream ds = new DataOutputStream(bs);
+
+	for (int i = 0; i < (in.length + 3) / 4; i++) {
+		short [] s = new short[4];
+		short [] t = new short[3];
+
+		for (int j = 0; j < 4; j++)
+			s[j] = (short) Base64.indexOf(in[i*4+j]);
+
+		t[0] = (short) ((s[0] << 2) + (s[1] >> 4));
+		if (s[2] == 64) {
+			t[1] = t[2] = (short) (-1);
+			if ((s[1] & 0xF) != 0)
+				return null;
+		}
+		else if (s[3] == 64) {
+			t[1] = (short) (((s[1] << 4) + (s[2] >> 2)) & 0xFF);
+			t[2] = (short) (-1);
+			if ((s[2] & 0x3) != 0)
+				return null;
+		}
+		else {
+			t[1] = (short) (((s[1] << 4) + (s[2] >> 2)) & 0xFF);
+			t[2] = (short) (((s[2] << 6) + s[3]) & 0xFF);
+		}
+
+		try {
+			for (int j = 0; j < 3; j++)
+				if (t[j] >= 0)
+					ds.writeByte(t[j]);
+		}
+		catch (IOException e) {
+		}
+	}
+	return bs.toByteArray();
+}
+
+}