SHA-1

LSL now includes its own (faster) llSHA1String function, which removes the need for the UTF8_SHA1 variant from this library. Also consider the more secure llSHA256String.
Performs a SHA-1 hash on the text. This is similar to an MD5 hash, but is slightly more secure. Two versions of the function are provided: one for UTF-8 strings (all strings in LSL are UTF-8) and another for Base64 strings (for which you need to specify the data length in bits).
There are also two SHA-2 script implementations (SHA-256 & SHA-224), though consider the faster llSHA256String provided by LSL itself.
View for more information.
//////////////////////////////////////////////////////////////////////////////////////
//
//	UTF-8 SHA-1 160
//	Version 1.3 
//	ESL Compiled: "Nov 26 2013", "00:11:59"
//	Copyright (C) 2013 Strife Onizuka
//	Based on Pseudo-code from http://en.wikipedia.org/wiki/SHA-1
//	https://wiki.secondlife.com/wiki/SHA-1
//
//	This library is free software; you can redistribute it and/or
//	modify it under the terms of the GNU Lesser General Public License
//	as published by the Free Software Foundation;
//	version 3 of the License.
//	
//	This library is distributed in the hope that it will be useful,
//	but WITHOUT ANY WARRANTY; without even the implied warranty of
//	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
//	GNU Lesser General Public License for more details.
//	
//	You should have received a copy of the GNU Lesser General Public License
//	along with this library. If not, see <http://www.gnu.org/licenses/>
//	or write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
//	Boston, MA 02111-1307 USA
//	
//////////////////////////////////////////////////////////////////////////////////////
//===================================================//
// Combined Library v1.0 //
// "Nov 26 2013", "00:11:59" //
// Copyright (C) 2004-2012, Strife Onizuka (cc-by) //
// http://creativecommons.org/licenses/by/3.0/ //
//===================================================//
//{
string hexc="0123456789ABCDEF";
//} Combined Library
string Base64_SHA1(string plain, integer bit_length) { 
 integer H1 = 0x67452301;
 integer H2 = 0xefcdab89;
 integer H3 = 0x98badcfe;
 integer H4 = 0x10325476;
 integer H5 = 0xc3d2e1f0;
 integer b = ((bit_length + 40) >> 5) | 15;//this works because we want the value to be one less than the next appropriate multiple of 16.
 string buf = "AAA";
 integer i = -5;
 do buf += buf; while((i = -~i));
 integer S = (6 * llSubStringIndex((plain)+"=", "="));
 integer T = 0x80000000;
 if(bit_length) {
 if(S < bit_length) {
 plain = llDeleteSubString(plain, S, 0x7FFFFFF0);
 i = ((bit_length + 23) / 24) * 24;
 do 
 plain += buf;
 while((S += 576) < i);
 }
 T = 23 - ((~-(bit_length)) % 24);
 T = (llBase64ToInteger(llGetSubString((llGetSubString(plain = llGetSubString(plain, 0, (bit_length / 6) | 3), -4, (~-(S / 6)))) + "AAAAA", 0, 5)) & (0xFFFFFF00 << T)) | (0x00000080 << T);
 }
 //llOwnerSay(llList2CSV([b,j, llStringLength(buf), llIntegerToBase64(j << (6 - ((b % 3) << 1)))]));
 plain = llInsertString( llDeleteSubString(plain, -4, -1) + 
 llGetSubString(llIntegerToBase64(T), 0, 5) + buf, (-~((b << 4) / 3)), 
 llGetSubString(llIntegerToBase64(bit_length << (6 - ((b % 3) << 1))), 0, 5));
 //llOwnerSay(llList2CSV([llStringLength(plain), Base64ToHex(plain), T]));
 list x;
 i = 0;
 do {
 integer A = H1;
 integer B = H2;
 integer C = H3;
 integer D = H4;
 integer E = H5;
 x = (list)(bit_length = 0);//the zero gets flushed off the stack by the later loops
 do {
 T = llBase64ToInteger(buf = llGetSubString(plain, T = ((i + bit_length) << 4) / 3, T+6)) << (S = ((i + bit_length) % 3) << 1);
 if(S)
 T = T | (llBase64ToInteger("A" + (llDeleteSubString(buf, 0, 1))) >> (6 - S));
// llOwnerSay("W["+(string)j+"]="+hex(T));
 x += T;
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (D ^ (B & (C ^ D))) + E + 0x5a827999;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(16 > (bit_length = -~bit_length));
//		llOwnerSay(llList2CSV(hexm(x)));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (D ^ (B & (C ^ D))) + E + 0x5a827999;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(20 > (bit_length = -~bit_length));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (B ^ C ^ D) + E + 0x6ed9eba1;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(40 > (bit_length = -~bit_length));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + ((B & C) | (B & D) | (C & D)) + E + 0x8f1bbcdc;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(60 > (bit_length = -~bit_length));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (B ^ C ^ D) + E + 0xca62c1d6;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(80 > (bit_length = -~bit_length));
 H1 += A;
 H2 += B;
 H3 += C;
 H4 += D;
 H5 += E;
 } while(b > (i += 16));
 x = [H1, H2, H3, H4, H5];
 i = -5;
 buf = "";
 do {
 T = llList2Integer(x,i);
 bit_length = 32;
 do {
 buf += llGetSubString(hexc, b = ((T >> (bit_length -= 4)) & 0xF), b);
 } while (bit_length);
 } while ((i = -~i));
 return buf;
}
string UTF8_SHA1(string plain) { 
 integer H1 = 0x67452301;
 integer H2 = 0xefcdab89;
 integer H3 = 0x98badcfe;
 integer H4 = 0x10325476;
 integer H5 = 0xc3d2e1f0;
 //ORing on the extra bit. Since we are working in base64 the byte bounderies aren't where we want them.
 //So we get the last byte group and append our extra bit onto it. It contains either 1, 2, or 3 bytes.
 integer j = llSubStringIndex((plain = llStringToBase64(plain))+"=", "=");
 integer T = 0x80000000;
 if(j) {
 j = (6 * (T = j)) & -8;//length in bits
 T = llBase64ToInteger(llGetSubString((llGetSubString(plain, -4, (~-(T)))) + "AAAA", 0, 5)) | (0x00000080 << ((j % 3) << 3));
 }
 integer b = ((j + 40) >> 5) | 15;//this works because we want the value to be one less than the next appropriate multiple of 16.
 string buf = "AAA";
 integer i = -5;
 do buf += buf; while((i = -~i));//We need 85, 96 is close enough
 //llOwnerSay(llList2CSV([b,j, llStringLength(buf), llIntegerToBase64(j << (6 - ((b % 3) << 1)))]));
 plain = llInsertString( llDeleteSubString(plain, -4, -1) + 
 llGetSubString(llIntegerToBase64(T), 0, 5) + buf, (b << 4) / 3, 
 llGetSubString(llIntegerToBase64(j >> ((b % 3) << 1)), 0, 5));
 //llOwnerSay(llList2CSV([llStringLength(plain), Base64ToHex(plain)]));
 list x;
 integer S = 0;
 do {
 integer A = H1;
 integer B = H2;
 integer C = H3;
 integer D = H4;
 integer E = H5;
 x = (list)(j = 0);//the zero gets flushed off the stack by the later loops
 do {
 T = llBase64ToInteger(buf = llGetSubString(plain, T = ((i + j) << 4) / 3, T+6)) << (S = ((i + j) % 3) << 1);
 if(S)
 T = T | (llBase64ToInteger("A" + (llDeleteSubString(buf, 0, 1))) >> (6 - S));
// llOwnerSay("W["+(string)j+"]="+hex(T));
 x += T;
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (D ^ (B & (C ^ D))) + E + 0x5a827999;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(16 > (j = -~j));
//		llOwnerSay(llList2CSV(hexm(x)));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (D ^ (B & (C ^ D))) + E + 0x5a827999;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(20 > (j = -~j));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (B ^ C ^ D) + E + 0x6ed9eba1;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(40 > (j = -~j));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + ((B & C) | (B & D) | (C & D)) + E + 0x8f1bbcdc;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(60 > (j = -~j));
 do {
 S = llList2Integer(x, -3) ^ llList2Integer(x, -8) ^ llList2Integer(x, -14) ^ llList2Integer(x, -16);
 x = llList2List(x + (T = ((S << 1) | !!(S & 0x80000000))), -16, -1);
// llOwnerSay("W["+(string)j+"]="+hex(T));
 T += ((A << 5) | ((A >> 27) & 0x1F)) + (B ^ C ^ D) + E + 0xca62c1d6;//k
 E = D;
 D = C;
 C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
 B = A;
 A = T;
 } while(80 > (j = -~j));
 H1 += A;
 H2 += B;
 H3 += C;
 H4 += D;
 H5 += E;
 } while(b > (i += 16));
 x = [H1, H2, H3, H4, H5];
 i = -5;
 buf = "";
 do {
 T = llList2Integer(x,i);
 j = 32;
 do {
 buf += llGetSubString(hexc, b = ((T >> (j -= 4)) & 0xF), b);
 } while (j);
 } while ((i = -~i));
 return buf;
}
integer go(string in, string answer) {
 llOwnerSay("");
 string b = llStringToBase64(in);
 integer len = (6 * llSubStringIndex((b)+"=", "=")) & -8;
 llResetTime();
 string outu = UTF8_SHA1(in);
 float tu = llGetTime();
 llOwnerSay(llList2CSV(([outu, tu, len])));
 llResetTime();
 string outb = Base64_SHA1(b, len);
 float tb = llGetTime();
 llOwnerSay(llList2CSV(([outb, tb, len])));
 if(answer) {
 llOwnerSay(llList2CSV(([answer, (answer == outu),(answer == outb)])));
 return (answer == outb) && (answer == outu);
 }
 return TRUE;
}
default
{
 state_entry()
 {
 if(Base64_SHA1("AAAA", 24) != "29E2DCFBB16F63BB0254DF7585A15BB6FB5E927D")
 llOwnerSay("Failed Base64_SHA1(\"AAAA\", 24)");
 if(go("", "DA39A3EE5E6B4B0D3255BFEF95601890AFD80709"))
 if(go("abc", "A9993E364706816ABA3E25717850C26C9CD0D89D"))
 if(go("The quick brown fox jumps over the lazy dog", "2FD4E1C67A2D28FCED849EE1BB76E7391B93EB12"))
 llOwnerSay("All Tests Passed!");
// llOwnerSay((string)llGetTime());
 }
}
 Category: LSL Encryption