AES LSL Examples

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AES LSL Examples

Description

The following LSL code snippets show examples of using the AES engine by Haravikk Mistral. These examples require that you add any relevant functions and constants from the helpers code where noted.

States are used in these scripts for clarity, but are not necessary to the operation the scripts themselves.

Examples

Encrypt a message

<lsl>string myKey = "1234567890ABCDEF0123456789ABCDEF"; // 128-bit key in hex string myMsg = "Hello world! I am a lovely message waiting to be encrypted!"; string myIV = "89ABCDEF0123456789ABCDEF01234567";

// Add necessary functions from https://wiki.secondlife.com/wiki/AES_LSL_Helpers here

default {

   state_entry() { // Setup the engine for use
       lslAESSetup(
           LINK_THIS,
           "MODE_CBC,"+     // CBC mode is a good, strong mode
           "PAD_NULLS,"+    // Pad with null-chars (zero-bytes)
           "PAD_SIZE,512",  // Pad into blocks of 512-bits
           llGetKey()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_SETUP) 
           state prime;
   }

}

state prime {

   state_entry() { // First prime the engine with a key
       lslAESPrimeHexKey(
           LINK_THIS,
           myKey,
           llGetKey()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_PRIME) 
           state init;
   }

}

state init {

   state_entry() { // Now init the engine with an input vector
       lslAESInitHexIV(
           LINK_THIS,
           myIV,
           llGetKey()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_INIT) 
           state encrypt;
   }

}

state encrypt {

   state_entry() { // Send our message
       lslAESEncryptBase64ToBase64(
           LINK_THIS,
           llStringToBase64(myMsg),
           llGetOwner()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_ENCRYPT) 
           llOwnerSay("Encrypted: "+msg);
   }

}</lsl>

Decrypt a message

<lsl>string myKey = "1234567890ABCDEF0123456789ABCDEF"; // 128-bit key in hex string myMsg = "slihkO6t9I/yfvfUpI0Rthagd/z8j1s5qh/PSbKGBg4N3PoQgUFdcCVnqOYku53cVx+IDgo8d0gPGaBR5YzORQ="; string myIV = "89ABCDEF0123456789ABCDEF01234567";

// Add necessary functions from https://wiki.secondlife.com/wiki/AES_LSL_Helpers here

default {

   state_entry() { // Setup the engine for use
       lslAESSetup(
           LINK_THIS,
           "MODE_CBC,"+     // CBC mode is a good, strong mode
           "PAD_NULLS,"+    // Pad with null-chars (zero-bytes)
           "PAD_SIZE,512",  // Pad into blocks of 512-bits
           llGetKey()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_SETUP) 
           state prime;
   }

}

state prime {

   state_entry() { // First prime the engine with a key
       lslAESPrimeHexKey(
           LINK_THIS,
           myKey,
           llGetKey()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_PRIME) 
           state init;
   }

}

state init {

   state_entry() { // Now init the engine with an input vector
       lslAESInitHexIV(
           LINK_THIS,
           myIV,
           llGetKey()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_INIT) 
           state decrypt;
   }

}

state decrypt {

   state_entry() { // Send our message
       lslAESEncryptBase64ToBase64(
           LINK_THIS,
           myMsg,
           llGetOwner()
       );
   }

   link_message(integer x, integer y, string msg, key id) {
       if (!lslAESIsReply(y, id)) return;
       
       y = lslAESGetReplyMode(y);
       if (y == LSLAES_COMMAND_ERROR) 
           llOwnerSay("ERROR: "+msg);
       else if (y == LSLAES_COMMAND_DECRYPT) 
           llOwnerSay("Decrypted: "+llBase64ToString(msg));
   }

}</lsl>