XTEA
Another XTEA implementation for LSL. Not sure if i have used the correct endian.
Changes
0.3
- Fixed length calculation
- Reduced loop logic, now parses backwards.
- Better memory cleanup.
- Less Vertical whitespace
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
Source
<lsl>//===================================================// // XTEA Library v0.3 // // "Dec 9 2007", "04:58:36" // // Copyright (C) 2004-2007, Strife Onizuka (cc-by) // // http://creativecommons.org/licenses/by/3.0/ // //===================================================// //{
string v; integer v0; integer v1;
string Base64_XTEA_Encipher(integer num_rounds, string in, list k) {
integer len = ((llStringLength(v = TrimRight(in,in="=")) * 6) >> 5); ReadBase64IntegerPair(len);//ReadBase64Integer could be used here instead if((len = ((len + (2 >> !v0)) & 0xFFFFFFFE)))//just a little length fudging do{ integer sum = 0; ReadBase64IntegerPair(len -= 2); 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(len); }while(len); return TrimRight(v, v = "A");
}
string Base64_XTEA_Decipher(integer num_rounds, string in, list k) {
integer len = ((llStringLength(v = TrimRight(in,in="=")) * 6) >> 5); ReadBase64IntegerPair(len);//ReadBase64Integer could be used here instead if((len = ((len + (2 >> !v0)) & 0xFFFFFFFE)))//just a little length fudging do{ integer sum = 0x9E3779B9 * num_rounds; ReadBase64IntegerPair(len -= 2); 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(len); }while(len); return TrimRight(v, v = "A");
}
//} XTEA Library
//===================================================// // Combined Library // // "Dec 9 2007", "04:58:36" // // 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 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
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([rounds, "~~~~"] + 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(d)])); llOwnerSay(llList2CSV([b, llBase64ToString(b)])); } }
}</lsl>