1 files changed, 130 insertions, 0 deletions
diff --git a/src/main/java/ch/ethz/ssh2/crypto/cipher/BlockCipherFactory.java b/src/main/java/ch/ethz/ssh2/crypto/cipher/BlockCipherFactory.java
new file mode 100644
index 0000000..1f93336
--- /dev/null
+++ b/src/main/java/ch/ethz/ssh2/crypto/cipher/BlockCipherFactory.java
@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2006-2011 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+package ch.ethz.ssh2.crypto.cipher;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Vector;
+
+/**
+ * BlockCipherFactory.
+ *
+ * @author Christian Plattner
+ * @version $Id: BlockCipherFactory.java 29 2011-05-28 21:28:32Z dkocher@sudo.ch $
+ */
+public class BlockCipherFactory
+{
+	private static final 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;
+		}
+	}
+
+	private static final List<CipherEntry> ciphers = new Vector<CipherEntry>();
+
+	static
+	{
+		/* Higher Priority First */
+		ciphers.add(new CipherEntry("aes128-ctr", 16, 16, "ch.ethz.ssh2.crypto.cipher.AES"));
+		ciphers.add(new CipherEntry("aes192-ctr", 16, 24, "ch.ethz.ssh2.crypto.cipher.AES"));
+		ciphers.add(new CipherEntry("aes256-ctr", 16, 32, "ch.ethz.ssh2.crypto.cipher.AES"));
+		ciphers.add(new CipherEntry("blowfish-ctr", 8, 16, "ch.ethz.ssh2.crypto.cipher.BlowFish"));
+
+		ciphers.add(new CipherEntry("aes128-cbc", 16, 16, "ch.ethz.ssh2.crypto.cipher.AES"));
+		ciphers.add(new CipherEntry("aes192-cbc", 16, 24, "ch.ethz.ssh2.crypto.cipher.AES"));
+		ciphers.add(new CipherEntry("aes256-cbc", 16, 32, "ch.ethz.ssh2.crypto.cipher.AES"));
+		ciphers.add(new CipherEntry("blowfish-cbc", 8, 16, "ch.ethz.ssh2.crypto.cipher.BlowFish"));
+
+		ciphers.add(new CipherEntry("3des-ctr", 8, 24, "ch.ethz.ssh2.crypto.cipher.DESede"));
+		ciphers.add(new CipherEntry("3des-cbc", 8, 24, "ch.ethz.ssh2.crypto.cipher.DESede"));
+	}
+
+	public static String[] getDefaultCipherList()
+	{
+		List<String> list = new ArrayList<String>(ciphers.size());
+		for (CipherEntry ce : ciphers)
+		{
+			list.add(ce.type);
+		}
+		return list.toArray(new String[ciphers.size()]);
+	}
+
+	public static void checkCipherList(String[] cipherCandidates)
+	{
+		for (String cipherCandidate : cipherCandidates)
+		{
+			getEntry(cipherCandidate);
+		}
+	}
+
+	//	@SuppressWarnings("rawtypes")
+	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 (ClassNotFoundException e)
+		{
+			throw new IllegalArgumentException("Cannot instantiate " + type, e);
+		}
+		catch (InstantiationException e)
+		{
+			throw new IllegalArgumentException("Cannot instantiate " + type, e);
+		}
+		catch (IllegalAccessException e)
+		{
+			throw new IllegalArgumentException("Cannot instantiate " + type, e);
+		}
+	}
+
+	private static CipherEntry getEntry(String type)
+	{
+		for (CipherEntry ce : ciphers)
+		{
+			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;
+	}
+}