1 files changed, 115 insertions, 0 deletions
diff --git a/sshlib/src/main/java/com/trilead/ssh2/crypto/cipher/BlockCipherFactory.java b/sshlib/src/main/java/com/trilead/ssh2/crypto/cipher/BlockCipherFactory.java
new file mode 100644
index 0000000..6e386a5
--- /dev/null
+++ b/sshlib/src/main/java/com/trilead/ssh2/crypto/cipher/BlockCipherFactory.java
@@ -0,0 +1,115 @@
+
+package com.trilead.ssh2.crypto.cipher;
+
+import java.util.Vector;
+
+/**
+ * BlockCipherFactory.
+ * 
+ * @author Christian Plattner, plattner@trilead.com
+ * @version $Id: BlockCipherFactory.java,v 1.2 2008/04/01 12:38:09 cplattne Exp $
+ */
+public class BlockCipherFactory
+{
+	static class CipherEntry
+	{
+		String type;
+		int blocksize;
+		int keysize;
+		String cipherClass;
+
+		public CipherEntry(String type, int blockSize, int keySize, String cipherClass)
+		{
+			this.type = type;
+			this.blocksize = blockSize;
+			this.keysize = keySize;
+			this.cipherClass = cipherClass;
+		}
+	}
+
+	static Vector<CipherEntry> ciphers = new Vector<CipherEntry>();
+
+	static
+	{
+		/* Higher Priority First */
+
+		ciphers.addElement(new CipherEntry("aes256-ctr", 16, 32, "com.trilead.ssh2.crypto.cipher.AES"));
+		ciphers.addElement(new CipherEntry("aes192-ctr", 16, 24, "com.trilead.ssh2.crypto.cipher.AES"));
+		ciphers.addElement(new CipherEntry("aes128-ctr", 16, 16, "com.trilead.ssh2.crypto.cipher.AES"));
+		ciphers.addElement(new CipherEntry("blowfish-ctr", 8, 16, "com.trilead.ssh2.crypto.cipher.BlowFish"));
+
+		ciphers.addElement(new CipherEntry("aes256-cbc", 16, 32, "com.trilead.ssh2.crypto.cipher.AES"));
+		ciphers.addElement(new CipherEntry("aes192-cbc", 16, 24, "com.trilead.ssh2.crypto.cipher.AES"));
+		ciphers.addElement(new CipherEntry("aes128-cbc", 16, 16, "com.trilead.ssh2.crypto.cipher.AES"));
+		ciphers.addElement(new CipherEntry("blowfish-cbc", 8, 16, "com.trilead.ssh2.crypto.cipher.BlowFish"));
+		
+		ciphers.addElement(new CipherEntry("3des-ctr", 8, 24, "com.trilead.ssh2.crypto.cipher.DESede"));
+		ciphers.addElement(new CipherEntry("3des-cbc", 8, 24, "com.trilead.ssh2.crypto.cipher.DESede"));
+	}
+
+	public static String[] getDefaultCipherList()
+	{
+		String list[] = new String[ciphers.size()];
+		for (int i = 0; i < ciphers.size(); i++)
+		{
+			CipherEntry ce = ciphers.elementAt(i);
+			list[i] = new String(ce.type);
+		}
+		return list;
+	}
+
+	public static void checkCipherList(String[] cipherCandidates)
+	{
+		for (int i = 0; i < cipherCandidates.length; i++)
+			getEntry(cipherCandidates[i]);
+	}
+
+	public static BlockCipher createCipher(String type, boolean encrypt, byte[] key, byte[] iv)
+	{
+		try
+		{
+			CipherEntry ce = getEntry(type);
+			Class cc = Class.forName(ce.cipherClass);
+			BlockCipher bc = (BlockCipher) cc.newInstance();
+
+			if (type.endsWith("-cbc"))
+			{
+				bc.init(encrypt, key);
+				return new CBCMode(bc, iv, encrypt);
+			}
+			else if (type.endsWith("-ctr"))
+			{
+				bc.init(true, key);
+				return new CTRMode(bc, iv, encrypt);
+			}
+			throw new IllegalArgumentException("Cannot instantiate " + type);
+		}
+		catch (Exception e)
+		{
+			throw new IllegalArgumentException("Cannot instantiate " + type);
+		}
+	}
+
+	private static CipherEntry getEntry(String type)
+	{
+		for (int i = 0; i < ciphers.size(); i++)
+		{
+			CipherEntry ce = ciphers.elementAt(i);
+			if (ce.type.equals(type))
+				return ce;
+		}
+		throw new IllegalArgumentException("Unkown algorithm " + type);
+	}
+
+	public static int getBlockSize(String type)
+	{
+		CipherEntry ce = getEntry(type);
+		return ce.blocksize;
+	}
+
+	public static int getKeySize(String type)
+	{
+		CipherEntry ce = getEntry(type);
+		return ce.keysize;
+	}
+}