2002/03/21 01:19:32

[org.ibex.core.git] / src / org / bouncycastle / crypto / StreamCipher.java

diff --git a/src/org/bouncycastle/crypto/StreamCipher.java b/src/org/bouncycastle/crypto/StreamCipher.java
new file mode 100644 (file)
index 0000000..6886e8c
--- /dev/null
+++ b/src/org/bouncycastle/crypto/StreamCipher.java
@@ -0,0 +1,53 @@
+package org.bouncycastle.crypto;
+
+/**
+ * the interface stream ciphers conform to.
+ */
+public interface StreamCipher
+{
+    /**
+     * Initialise the cipher.
+     *
+     * @param forEncryption if true the cipher is initialised for
+     *  encryption, if false for decryption.
+     * @param param the key and other data required by the cipher.
+     * @exception IllegalArgumentException if the params argument is
+     * inappropriate.
+     */
+    public void init(boolean forEncryption, CipherParameters params)
+        throws IllegalArgumentException;
+
+    /**
+     * Return the name of the algorithm the cipher implements.
+     *
+     * @return the name of the algorithm the cipher implements.
+     */
+    public String getAlgorithmName();
+
+    /**
+     * encrypt/decrypt a single byte returning the result.
+     *
+     * @param in the byte to be processed.
+     * @return the result of processing the input byte.
+     */
+    public byte returnByte(byte in);
+
+    /**
+     * process a block of bytes from in putting the result into out.
+     *
+     * @param in the input byte array.
+     * @param inOff the offset into the in array where the data to be processed starts.
+     * @param len the number of bytes to be processed.
+     * @param out the output buffer the processed bytes go into.
+     * @param outOff the offset into the output byte array the processed data stars at.
+     * @exception DataLengthException if the output buffer is too small.
+     */
+    public void processBytes(byte[] in, int inOff, int len, byte[] out, int outOff)
+        throws DataLengthException;
+
+    /**
+     * reset the cipher. This leaves it in the same state
+     * it was at after the last init (if there was one).
+     */
+    public void reset();
+}