Difference between revisions of "XTEA"

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Another XTEA implementation for LSL. Not sure if i have used the correct endian.
Another XTEA implementation for LSL. Not sure if i have used the correct endian.
===Known Issues===
*Calculating the length properly is difficult. An appropriate solution has not yet determined.
===Future Changes===
*Move index parameter into a global?
*Combine Decipher and Cipher, then inline Read & Write functions?
===Changes===
====0.2====
*Uses globals cutting down on instances and copies, should result in a huge time and bytecode savings.
*Base64 functions moved from XTEA in to CL.
*All functions optimized further.
*Introduction of ReadBase64IntegerPair - By doing read and writes this way it reduces bytecode.
====0.1====
*Initial Release


<lsl>//===================================================//
<lsl>//===================================================//
//                XTEA Library v0.1                 //
//                XTEA Library v0.2                 //
//            "Dec  7 2007", "03:00:09"            //
//            "Dec  8 2007", "16:57:27"            //
//  Copyright (C) 2004-2007, Strife Onizuka (cc-by)  //
//  Copyright (C) 2004-2007, Strife Onizuka (cc-by)  //
//    http://creativecommons.org/licenses/by/3.0/    //
//    http://creativecommons.org/licenses/by/3.0/    //
Line 10: Line 28:
//===================================================//
//===================================================//
//                Combined Library                  //
//                Combined Library                  //
//            "Dec  7 2007", "03:00:09"            //
//            "Dec  8 2007", "16:57:27"            //
//  Copyright (C) 2004-2007, Strife Onizuka (cc-by)  //
//  Copyright (C) 2004-2007, Strife Onizuka (cc-by)  //
//    http://creativecommons.org/licenses/by/3.0/    //
//    http://creativecommons.org/licenses/by/3.0/    //
Line 21: Line 39:
//Mono is the future VM for LSL, LSO is the current VM of LSL.
//Mono is the future VM for LSL, LSO is the current VM of LSL.
//To achieve safety, the functions require more bytecode and sacrifice a bit of performance.
//To achieve safety, the functions require more bytecode and sacrifice a bit of performance.
string Base64Pad(string in)
{
    integer len = llStringLength(in);
    return in + llDeleteSubString("AAAA", 1, len % 4);
}


string TrimRight(string src, string chrs)//Mono Safe, LSO Safe
string TrimRight(string src, string chrs)//Mono Safe, LSO Safe
Line 27: Line 51:
     integer j = i;
     integer j = i;
     do ; while(~llSubStringIndex(chrs, llGetSubString(src, i = (~-(j = i)), i)) && j);
     do ; while(~llSubStringIndex(chrs, llGetSubString(src, i = (~-(j = i)), i)) && j);
     return llDeleteSubString(src, j, 0xFFFF);
     return llDeleteSubString(src, j, 0x7FFFFFF0);
}
}


//} Combined Library
ReadBase64IntegerPair(integer index)
{
    integer S = (index << 5) % 6;
    string buf = llGetSubString(v, index = ((index << 5) / 6), index + 11);
    index = llBase64ToInteger(llGetSubString("A" + (llDeleteSubString(buf, 0, 2)) + "AAAAA", 0, 5));
 
        v0 = (llBase64ToInteger(llGetSubString((buf) + "AAAAAA", 0, 5)) << S) | (index >> (12 - S));
        v1 = ((llBase64ToInteger(llGetSubString((llDeleteSubString(buf,0,5)) + "AAAAAA", 0, 5)) >> (4 - S)) & ~(0xF0000000 << S)) | (index << (20 + S));


integer ReadBase64Integer(string data, integer index)
{
    integer S = (index % 3) << 1;
    index = llBase64ToInteger(llGetSubString((data = llGetSubString(data, index = ((index << 4) / 3), index+6)) + "AAAAAA", 0, 5)) << S;
    if(S)
        return index | (llBase64ToInteger(llGetSubString("A" + (llDeleteSubString(data, 0, 1)) + "AAAAA", 0, 5)) >> (6 - S));
    return index;
}
}


string WriteBase64IntegerPair(string data, integer index, integer low, integer high)
WriteBase64IntegerPair(integer index)
{
{
    integer S = ((index % 3) << 1);


     return llDeleteSubString(
     integer S = 10 - ((index << 5) % 6);
    v = llDeleteSubString(
                 llInsertString(
                 llInsertString(
                     data,
                     v,
                     index = ((index << 4) / 3),
                     index = ((index << 5) / 6),
                     llInsertString(
                     llInsertString(
                         llInsertString(
                         llInsertString(
                             llIntegerToBase64(
                             llIntegerToBase64(
                                 (llBase64ToInteger(llGetSubString((data = llGetSubString(data, index, index + 12)) + "AAAAAA", 0, 5)) & (0xFC000000 << (6 - S))) |  
                                 (llBase64ToInteger(llGetSubString((v = llGetSubString(v, index, index + 12)) + "AAAAAA", 0, 5)) & (0xFFC00000 << S)) |  
                                 ((low >> S) & ~(0xFC000000 << (6 - S)))
                                 ((v0 >> (10 - S)) & ~(0xFFC00000 << S))
                             ),
                             ),
                             3,
                             3,
                             llIntegerToBase64(
                             llIntegerToBase64(
                                 ((high >> (S + 14)) & ~(-1 << (18 - S))) |  
                                 ((v1 >> (24 - S)) & ~(0xFFFFFF00 << S)) |  
                                 (low << (18 - S))
                                 (v0 << (8 + S))
                             )
                             )
                         ),
                         ),
                         7,
                         7,
                         llIntegerToBase64(
                         llIntegerToBase64(
                             (llBase64ToInteger(llGetSubString((llDeleteSubString(data, 0, 6)) + "AAAAAA", 0, 5)) & ~(-1 << (10 - S))) |  
                             (llBase64ToInteger(llGetSubString((llDeleteSubString(v, 0, 6)) + "AAAAAA", 0, 5)) & ~(0xFFFFFFFF << S)) |  
                             (high << (10 - S))
                             (v1 << S)
                         )
                         )
                     )
                     )
Line 71: Line 95:
                 index + 35
                 index + 35
             );
             );
}
HexToBase64(string a)
{
    v = "";
integer e = (llStringLength(a = (a + "0000000000000000")) - 9) & 0xFFFFFFF8;
integer g;
do
{
        v0 = ((integer)("0x"+(llGetSubString(a, g, g + 7)))); v1 = ((integer)("0x"+(llGetSubString(a, g + 8, g + 15)))); WriteBase64IntegerPair(g >> 3);
}while((g += 16) < e);


}
}


integer delta = 0x9E3779B9;
//} Combined Library
 
string v;
integer v0;
integer v1;


string Base64_XTEA_Encipher(integer num_rounds, string v, list k) {
string Base64_XTEA_Encipher(integer num_rounds, string in, list k) {


     integer len = llStringLength(v = TrimRight(v,"A="));
     integer len = (((llStringLength(v = TrimRight(in,in="=")) + 4) * 6) >> 5) & 0xFFFFFFFE;


     integer i = 0;
     integer i = -2;
     for(len = (3 * (len + 4)) >> 4; i < len; i += 2)
     while((i += 2) < len)
     {
     {
         integer sum = 0;
         integer sum = 0;
         integer v0  = ReadBase64Integer(v, i);
         ReadBase64IntegerPair(i);
        integer v1  = ReadBase64Integer(v, (-~(i)));
         integer j = (-~(num_rounds));
         integer j = (-~(num_rounds));
         while((j = ~-j)){
         while((j = ~-j)){
             v0 += (((v1 << 4) ^ ((v1 >> 5) & 0x07FFFFFF)) + v1) ^ (sum + llList2Integer(k, sum & 3));
             v0 += (((v1 << 4) ^ ((v1 >> 5) & 0x07FFFFFF)) + v1) ^ (sum + llList2Integer(k, sum & 3));
             sum += delta;
             sum += 0x9E3779B9;
             v1 += (((v0 << 4) ^ ((v0 >> 5) & 0x07FFFFFF)) + v0) ^ (sum + llList2Integer(k, (sum >> 11) & 3));
             v1 += (((v0 << 4) ^ ((v0 >> 5) & 0x07FFFFFF)) + v0) ^ (sum + llList2Integer(k, (sum >> 11) & 3));
         }
         }
 
         WriteBase64IntegerPair(i);
         v = WriteBase64IntegerPair(v, i, v0, v1);
     }
     }


     return TrimRight(v,"A");
     return TrimRight(v, "A");


}
}


string Base64_XTEA_Decipher(integer num_rounds, string v, list k) {
string Base64_XTEA_Decipher(integer num_rounds, string in, list k) {


     integer len = llStringLength(v = TrimRight(v,"A="));
     integer len = (((llStringLength(v = TrimRight(in,in="=")) + 4) * 6) >> 5) & 0xFFFFFFFE;


     integer i = 0;
     integer i = -2;
     for(len = (3 * (len + 4)) >> 4; i < len; i += 2)
     while((i += 2) < len)
     {
     {
         integer sum = delta * num_rounds;
         integer sum = 0x9E3779B9 * num_rounds;
         integer v0  = ReadBase64Integer(v, i);
         ReadBase64IntegerPair(i);
        integer v1  = ReadBase64Integer(v, (-~(i)));
         integer j = (-~(num_rounds));
         integer j = (-~(num_rounds));
         while((j = ~-j)){
         while((j = ~-j)){
             v1 -= (((v0 << 4) ^ ((v0 >> 5) & 0x07FFFFFF)) + v0) ^ (sum + llList2Integer(k, (sum >> 11) & 3));
             v1 -= (((v0 << 4) ^ ((v0 >> 5) & 0x07FFFFFF)) + v0) ^ (sum + llList2Integer(k, (sum >> 11) & 3));
             sum -= delta;
             sum -= 0x9E3779B9;
             v0 -= (((v1 << 4) ^ ((v1 >> 5) & 0x07FFFFFF)) + v1) ^ (sum + llList2Integer(k, sum & 3));
             v0 -= (((v1 << 4) ^ ((v1 >> 5) & 0x07FFFFFF)) + v1) ^ (sum + llList2Integer(k, sum & 3));
         }
         }
         v = WriteBase64IntegerPair(v, i, v0, v1);
         WriteBase64IntegerPair(i);
     }
     }


     return TrimRight(v,"A");
     return TrimRight(v, "A");


}
}
Line 136: Line 172:
         llListen(2, "", owner, "");
         llListen(2, "", owner, "");
         llListen(3, "", owner, "");
         llListen(3, "", owner, "");
        llListen(4, "", owner, "");
        llListen(5, "", owner, "");


     }
     }
Line 151: Line 189:
         {
         {
             rounds = (integer)d;
             rounds = (integer)d;
            llOwnerSay(llList2CSV([rounds, "~~~~"] + mk));
         }
         }
         else if(a == 3)
         else if(a == 3)
         {
         {
             b = TrimRight(llStringToBase64(d), "=");
             v = TrimRight(llStringToBase64(d), "=");
             mk = [ReadBase64Integer(b, 0), ReadBase64Integer(b, 1), ReadBase64Integer(b, 2), ReadBase64Integer(b, 3)];
            ReadBase64IntegerPair(0);
             llOwnerSay(llList2CSV(mk));
             mk = [v0,v1];
            ReadBase64IntegerPair(2);
            mk += [v0,v1];
            llOwnerSay(llList2CSV([rounds, "~~~~"] + mk));
        }
        else if(a == 4)
        {
            HexToBase64(d);
            ReadBase64IntegerPair(0);
            mk = [v0,v1];
            ReadBase64IntegerPair(2);
            mk += [v0,v1];
             llOwnerSay(llList2CSV([rounds, "~~~~"] + mk));
         }
         }
         else
         else
         {
         {
 
            if(a == 5)
 
                HexToBase64(d);
             llOwnerSay(b = d = llStringToBase64(d));
            else
 
                v = llStringToBase64(d);
             llOwnerSay(d = Base64_XTEA_Encipher(rounds, b, mk));
             llOwnerSay(b = d = v);
             llOwnerSay(llList2CSV([d = Base64_XTEA_Decipher(rounds, d, mk), llBase64ToString(d)]));
             llOwnerSay(llList2CSV([d = Base64_XTEA_Encipher(rounds, b, mk)]));
             llOwnerSay(llList2CSV([b,llBase64ToString(b)]));
             llOwnerSay(llList2CSV([d = Base64_XTEA_Decipher(rounds, d, mk), llBase64ToString(Base64Pad(d))]));
             llOwnerSay(llList2CSV([b, llBase64ToString(Base64Pad(b))]));
         }
         }
     }
     }
}</lsl>
}</lsl>

Revision as of 14:56, 8 December 2007

Another XTEA implementation for LSL. Not sure if i have used the correct endian.

Known Issues

  • Calculating the length properly is difficult. An appropriate solution has not yet determined.

Future Changes

  • Move index parameter into a global?
  • Combine Decipher and Cipher, then inline Read & Write functions?

Changes

0.2

  • Uses globals cutting down on instances and copies, should result in a huge time and bytecode savings.
  • Base64 functions moved from XTEA in to CL.
  • All functions optimized further.
  • Introduction of ReadBase64IntegerPair - By doing read and writes this way it reduces bytecode.

0.1

  • Initial Release

<lsl>//===================================================// // XTEA Library v0.2 // // "Dec 8 2007", "16:57:27" // // Copyright (C) 2004-2007, Strife Onizuka (cc-by) // // http://creativecommons.org/licenses/by/3.0/ // //===================================================//

//===================================================// // Combined Library // // "Dec 8 2007", "16:57:27" // // Copyright (C) 2004-2007, Strife Onizuka (cc-by) // // http://creativecommons.org/licenses/by/3.0/ // //===================================================// //{

//Functions marked "Mono Safe" are safe for use in LSLEditor & Mono //Functions marked "LSO Safe" are safe for use in LSO //Functions marked "Double Safe" are safe for use in VM's that support doubles (Mono, LSLEditor). //Mono is the future VM for LSL, LSO is the current VM of LSL. //To achieve safety, the functions require more bytecode and sacrifice a bit of performance.

string Base64Pad(string in) { 

   integer len = llStringLength(in);
   return in + llDeleteSubString("AAAA", 1, len % 4);

}

string TrimRight(string src, string chrs)//Mono Safe, LSO Safe { 

   integer i = llStringLength(src);
   integer j = i;
   do ; while(~llSubStringIndex(chrs, llGetSubString(src, i = (~-(j = i)), i)) && j);
   return llDeleteSubString(src, j, 0x7FFFFFF0);

}

ReadBase64IntegerPair(integer index) { 

   integer S = (index << 5) % 6;
   string buf = llGetSubString(v, index = ((index << 5) / 6), index + 11);
   index = llBase64ToInteger(llGetSubString("A" + (llDeleteSubString(buf, 0, 2)) + "AAAAA", 0, 5));

       v0 = (llBase64ToInteger(llGetSubString((buf) + "AAAAAA", 0, 5)) << S) | (index >> (12 - S));
       v1 = ((llBase64ToInteger(llGetSubString((llDeleteSubString(buf,0,5)) + "AAAAAA", 0, 5)) >> (4 - S)) & ~(0xF0000000 << S)) | (index << (20 + S));

}

WriteBase64IntegerPair(integer index) { 

   integer S = 10 - ((index << 5) % 6);
   v =  llDeleteSubString(
               llInsertString(
                   v,
                   index = ((index << 5) / 6),
                   llInsertString(
                       llInsertString(
                           llIntegerToBase64(
                               (llBase64ToInteger(llGetSubString((v = llGetSubString(v, index, index + 12)) + "AAAAAA", 0, 5)) & (0xFFC00000 << S)) | 
                               ((v0 >> (10 - S)) & ~(0xFFC00000 << S))
                           ),
                           3,
                           llIntegerToBase64(
                               ((v1 >> (24 - S)) & ~(0xFFFFFF00 << S)) | 
                               (v0 << (8 + S))
                           )
                       ),
                       7,
                       llIntegerToBase64(
                           (llBase64ToInteger(llGetSubString((llDeleteSubString(v, 0, 6)) + "AAAAAA", 0, 5)) & ~(0xFFFFFFFF << S)) | 
                           (v1 << S)
                       )
                   )
               ),
               index + 12,
               index + 35
           );

}

HexToBase64(string a) { 

   v = "";

integer e = (llStringLength(a = (a + "0000000000000000")) - 9) & 0xFFFFFFF8; integer g; do { 

       v0 = ((integer)("0x"+(llGetSubString(a, g, g + 7)))); v1 = ((integer)("0x"+(llGetSubString(a, g + 8, g + 15)))); WriteBase64IntegerPair(g >> 3);

}while((g += 16) < e);

}

//} Combined Library

string v; integer v0; integer v1;

string Base64_XTEA_Encipher(integer num_rounds, string in, list k) { 

   integer len = (((llStringLength(v = TrimRight(in,in="=")) + 4) * 6) >> 5) & 0xFFFFFFFE;

   integer i = -2;
   while((i += 2) < len)
   {
       integer sum = 0;
       ReadBase64IntegerPair(i);
       integer j = (-~(num_rounds));
       while((j = ~-j)){
           v0 += (((v1 << 4) ^ ((v1 >> 5) & 0x07FFFFFF)) + v1) ^ (sum + llList2Integer(k, sum & 3));
           sum += 0x9E3779B9;
           v1 += (((v0 << 4) ^ ((v0 >> 5) & 0x07FFFFFF)) + v0) ^ (sum + llList2Integer(k, (sum >> 11) & 3));
       }
       WriteBase64IntegerPair(i);
   }

   return TrimRight(v, "A");

}

string Base64_XTEA_Decipher(integer num_rounds, string in, list k) { 

   integer len = (((llStringLength(v = TrimRight(in,in="=")) + 4) * 6) >> 5) & 0xFFFFFFFE;

   integer i = -2;
   while((i += 2) < len)
   {
       integer sum = 0x9E3779B9 * num_rounds;
       ReadBase64IntegerPair(i);
       integer j = (-~(num_rounds));
       while((j = ~-j)){
           v1 -= (((v0 << 4) ^ ((v0 >> 5) & 0x07FFFFFF)) + v0) ^ (sum + llList2Integer(k, (sum >> 11) & 3));
           sum -= 0x9E3779B9;
           v0 -= (((v1 << 4) ^ ((v1 >> 5) & 0x07FFFFFF)) + v1) ^ (sum + llList2Integer(k, sum & 3));
       }
       WriteBase64IntegerPair(i);
   }

   return TrimRight(v, "A");

}

list mk; integer rounds = 128;

default { 

   state_entry()
   {
       key owner = llGetOwner();
       llListen(0, "", owner, "");
       llListen(1, "", owner, "");
       llListen(2, "", owner, "");
       llListen(3, "", owner, "");
       llListen(4, "", owner, "");
       llListen(5, "", owner, "");

   }
   listen(integer a, string b, key c, string d)
   {
       if(a == 1)
       {
           mk = [];
           list e = llCSV2List(d);
           for(a = 0; a < 3; ++a)
               mk += (integer)llList2String(e,a);
           llOwnerSay(llList2CSV(mk));
       }
       else if(a == 2)
       {
           rounds = (integer)d;
           llOwnerSay(llList2CSV([rounds, "~~~~"] + mk));
       }
       else if(a == 3)
       {
           v = TrimRight(llStringToBase64(d), "=");
           ReadBase64IntegerPair(0);
           mk = [v0,v1];
           ReadBase64IntegerPair(2);
           mk += [v0,v1];
           llOwnerSay(llList2CSV([rounds, "~~~~"] + mk));
       }
       else if(a == 4)
       {
           HexToBase64(d);
           ReadBase64IntegerPair(0);
           mk = [v0,v1];
           ReadBase64IntegerPair(2);
           mk += [v0,v1];
           llOwnerSay(llList2CSV([rounds, "~~~~"] + mk));
       }
       else
       {
           if(a == 5)
               HexToBase64(d);
           else
               v = llStringToBase64(d);
           llOwnerSay(b = d = v);
           llOwnerSay(llList2CSV([d = Base64_XTEA_Encipher(rounds, b, mk)]));
           llOwnerSay(llList2CSV([d = Base64_XTEA_Decipher(rounds, d, mk), llBase64ToString(Base64Pad(d))]));
           llOwnerSay(llList2CSV([b, llBase64ToString(Base64Pad(b))]));
       }
   }

}</lsl>

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