com.trilead.ssh2.crypto.digest.MAC Maven / Gradle / Ivy
package com.trilead.ssh2.crypto.digest;
/**
* MAC.
*
* @author Christian Plattner, [email protected]
* @version $Id: MAC.java,v 1.1 2007/10/15 12:49:57 cplattne Exp $
*/
public final class MAC
{
Digest mac;
int size;
public final static String[] getMacList()
{
/* Higher Priority First */
return new String[] { "hmac-sha1-96", "hmac-sha1", "hmac-md5-96", "hmac-md5" };
}
public final static void checkMacList(String[] macs)
{
for (int i = 0; i < macs.length; i++)
getKeyLen(macs[i]);
}
public final 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 final 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 final void update(byte[] packetdata, int off, int len)
{
mac.update(packetdata, off, len);
}
public final void getMac(byte[] out, int off)
{
mac.digest(out, off);
}
public final int size()
{
return size;
}
}