1 files changed, 91 insertions, 0 deletions
diff --git a/src/main/java/ch/ethz/ssh2/crypto/digest/MAC.java b/src/main/java/ch/ethz/ssh2/crypto/digest/MAC.java
new file mode 100644
index 0000000..ab40de3
--- /dev/null
+++ b/src/main/java/ch/ethz/ssh2/crypto/digest/MAC.java
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2006-2011 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+package ch.ethz.ssh2.crypto.digest;
+
+/**
+ * MAC.
+ *
+ * @author Christian Plattner
+ * @version 2.50, 03/15/10
+ */
+public final class MAC
+{
+	Digest mac;
+	int size;
+
+	public static String[] getMacList()
+	{
+		/* Higher Priority First */
+
+		return new String[]{"hmac-sha1-96", "hmac-sha1", "hmac-md5-96", "hmac-md5"};
+	}
+
+	public static void checkMacList(String[] macs)
+	{
+		for (int i = 0; i < macs.length; i++)
+			getKeyLen(macs[i]);
+	}
+
+	public static int getKeyLen(String type)
+	{
+		if (type.equals("hmac-sha1"))
+			return 20;
+		if (type.equals("hmac-sha1-96"))
+			return 20;
+		if (type.equals("hmac-md5"))
+			return 16;
+		if (type.equals("hmac-md5-96"))
+			return 16;
+		throw new IllegalArgumentException("Unkown algorithm " + type);
+	}
+
+	public MAC(String type, byte[] key)
+	{
+		if (type.equals("hmac-sha1"))
+		{
+			mac = new HMAC(new SHA1(), key, 20);
+		}
+		else if (type.equals("hmac-sha1-96"))
+		{
+			mac = new HMAC(new SHA1(), key, 12);
+		}
+		else if (type.equals("hmac-md5"))
+		{
+			mac = new HMAC(new MD5(), key, 16);
+		}
+		else if (type.equals("hmac-md5-96"))
+		{
+			mac = new HMAC(new MD5(), key, 12);
+		}
+		else
+			throw new IllegalArgumentException("Unkown algorithm " + type);
+
+		size = mac.getDigestLength();
+	}
+
+	public void initMac(int seq)
+	{
+		mac.reset();
+		mac.update((byte) (seq >> 24));
+		mac.update((byte) (seq >> 16));
+		mac.update((byte) (seq >> 8));
+		mac.update((byte) (seq));
+	}
+
+	public void update(byte[] packetdata, int off, int len)
+	{
+		mac.update(packetdata, off, len);
+	}
+
+	public void getMac(byte[] out, int off)
+	{
+		mac.digest(out, off);
+	}
+
+	public int size()
+	{
+		return size;
+	}
+}