diff -r 000000000000 -r 598d09faf89c aeslua/ciphermode.lua
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/aeslua/ciphermode.lua	Wed Feb 16 20:29:33 2011 +0000
@@ -0,0 +1,148 @@
+local aes = require("aeslua.aes");
+local util = require("aeslua.util");
+local buffer = require("aeslua.buffer");
+
+local public = {};
+
+local aeslua = require("aeslua");
+aeslua.ciphermode = public;
+
+--
+-- Encrypt strings
+-- key - byte array with key
+-- string - string to encrypt
+-- modefunction - function for cipher mode to use
+--
+function public.encryptString(key, data, modeFunction)
+    local iv = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    local keySched = aes.expandEncryptionKey(key);
+    local encryptedData = buffer.new();
+    
+    for i = 1, #data/16 do
+        local offset = (i-1)*16 + 1;
+        local byteData = {string.byte(data,offset,offset +15)};
+		
+        modeFunction(keySched, byteData, iv);
+
+        buffer.addString(encryptedData, string.char(unpack(byteData)));    
+    end
+    
+    return buffer.toString(encryptedData);
+end
+
+--
+-- the following 4 functions can be used as 
+-- modefunction for encryptString
+--
+
+-- Electronic code book mode encrypt function
+function public.encryptECB(keySched, byteData, iv) 
+	aes.encrypt(keySched, byteData, 1, byteData, 1);
+end
+
+-- Cipher block chaining mode encrypt function
+function public.encryptCBC(keySched, byteData, iv) 
+    util.xorIV(byteData, iv);
+
+    aes.encrypt(keySched, byteData, 1, byteData, 1);    
+        
+    for j = 1,16 do
+        iv[j] = byteData[j];
+    end
+end
+
+-- Output feedback mode encrypt function
+function public.encryptOFB(keySched, byteData, iv) 
+    aes.encrypt(keySched, iv, 1, iv, 1);
+    util.xorIV(byteData, iv);
+end
+
+-- Cipher feedback mode encrypt function
+function public.encryptCFB(keySched, byteData, iv) 
+    aes.encrypt(keySched, iv, 1, iv, 1);    
+    util.xorIV(byteData, iv);
+       
+    for j = 1,16 do
+        iv[j] = byteData[j];
+    end        
+end
+
+--
+-- Decrypt strings
+-- key - byte array with key
+-- string - string to decrypt
+-- modefunction - function for cipher mode to use
+--
+function public.decryptString(key, data, modeFunction)
+    local iv = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    
+    local keySched;
+    if (modeFunction == public.decryptOFB or modeFunction == public.decryptCFB) then
+    	keySched = aes.expandEncryptionKey(key);
+   	else
+   		keySched = aes.expandDecryptionKey(key);
+    end
+    
+    local decryptedData = buffer.new();
+
+    for i = 1, #data/16 do
+        local offset = (i-1)*16 + 1;
+        local byteData = {string.byte(data,offset,offset +15)};
+
+		iv = modeFunction(keySched, byteData, iv);
+
+        buffer.addString(decryptedData, string.char(unpack(byteData)));
+    end
+
+    return buffer.toString(decryptedData);    
+end
+
+--
+-- the following 4 functions can be used as 
+-- modefunction for decryptString
+--
+
+-- Electronic code book mode decrypt function
+function public.decryptECB(keySched, byteData, iv) 
+
+    aes.decrypt(keySched, byteData, 1, byteData, 1);
+    
+    return iv;
+end
+
+-- Cipher block chaining mode decrypt function
+function public.decryptCBC(keySched, byteData, iv) 
+	local nextIV = {};
+    for j = 1,16 do
+        nextIV[j] = byteData[j];
+    end
+        
+    aes.decrypt(keySched, byteData, 1, byteData, 1);    
+    util.xorIV(byteData, iv);
+
+	return nextIV;
+end
+
+-- Output feedback mode decrypt function
+function public.decryptOFB(keySched, byteData, iv) 
+    aes.encrypt(keySched, iv, 1, iv, 1);
+    util.xorIV(byteData, iv);
+    
+    return iv;
+end
+
+-- Cipher feedback mode decrypt function
+function public.decryptCFB(keySched, byteData, iv) 
+    local nextIV = {};
+    for j = 1,16 do
+        nextIV[j] = byteData[j];
+    end
+
+    aes.encrypt(keySched, iv, 1, iv, 1);
+        
+    util.xorIV(byteData, iv);
+    
+    return nextIV;
+end
+
+return public;