Difference between revisions of "User:Pedro Oval/Base64 HMAC SHA-1"

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(Add a group of test vectors and a TODO list)
(Repair missing variable error (thanks to Ghost Menjou for the report))
Line 146: Line 146:
         bit_length = 32;
         bit_length = 32;
         do
         do
             buf += llGetSubString(hexc, b = ((T >> (bit_length -= 4)) & 0xF), b);
             buf += llGetSubString("0123456789abcdef", b = ((T >> (bit_length -= 4)) & 0xF), b);
         while (bit_length);
         while (bit_length);
     }while ((i = -~i));
     }while ((i = -~i));

Revision as of 15:46, 25 September 2014

TODO: Add some text here, add padding test vectors

<lsl> string HexToBase64Unpadded(string a) {

   integer i = 0;
   integer len = llStringLength(a += "0000") - 4;
   string res = "";
   while (i < len)
   {
       res += llGetSubString(llIntegerToBase64(4*(integer)("0x" + llGetSubString(a, i, i+5))), 1, 4);
       i += 6;
   }
   return llGetSubString(res, 0, len*2/3);

}

string RemovePadding(string b64) // specialized - it won't work if the string consists of all "=" {

   integer i;
   do ; while(llGetSubString(b64, i = ~-i, i) == "=");
   return llGetSubString(b64, 0, i);

}

list Base64SHA1Compress(string b64, integer H1, integer H2, integer H3, integer H4, integer H5, integer i) {

   integer A = H1;
   integer B = H2;
   integer C = H3;
   integer D = H4;
   integer E = H5;
   integer round;
   integer S = 0;
   integer T;
   list x = [];
   string buf;
   do
   {
       T = llBase64ToInteger(buf = llGetSubString(b64, T = ((i + round) << 4) / 3, T+6)) << (S = ((i + round) % 3) << 1);
       if(S)
           T = T | (llBase64ToInteger("A" + (llDeleteSubString(buf, 0, 1))) >> (6 - S));

// llOwnerSay("W["+(string)round+"]="+hex(T));

       x += T;
       T += ((A << 5) | ((A >> 27) & 0x1F)) + (D ^ (B & (C ^ D))) + E + 0x5a827999;
       E = D;
       D = C;
       C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
       B = A;
       A = T;
   }while(16 > (round = -~round));

// 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)round+"]="+hex(T));

       T += ((A << 5) | ((A >> 27) & 0x1F)) + (D ^ (B & (C ^ D))) + E + 0x5a827999;
       E = D;
       D = C;
       C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
       B = A;
       A = T;
   }while(20 > (round = -~round));
   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)round+"]="+hex(T));

       T += ((A << 5) | ((A >> 27) & 0x1F)) + (B ^ C ^ D) + E + 0x6ed9eba1;
       E = D;
       D = C;
       C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
       B = A;
       A = T;
   }while(40 > (round = -~round));
   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)round+"]="+hex(T));

       T += ((A << 5) | ((A >> 27) & 0x1F)) + ((B & C) | (B & D) | (C & D)) + E + 0x8f1bbcdc;
       E = D;
       D = C;
       C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
       B = A;
       A = T;
   }while(60 > (round = -~round));
   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)round+"]="+hex(T));

       T += ((A << 5) | ((A >> 27) & 0x1F)) + (B ^ C ^ D) + E + 0xca62c1d6;
       E = D;
       D = C;
       C = ((B << 30) | ((B >> 2) & 0x3FFFFFFF));
       B = A;
       A = T;
   }while(80 > (round = -~round));
   return [H1+A, H2+B, H3+C, H4+D, H5+E];

}

string Base64SHA1forHMAC(string b64, integer bit_length, integer extra_bit_length, integer H1, integer H2, integer H3, integer H4, integer H5) {

   //OR on the extra bit.
   integer b = ((bit_length + 40) >> 5) | 15;
   integer T = llBase64ToInteger(RemovePadding(llGetSubString(b64, -4, -1)) + "AAAA");
   string buf = "AAA";
   integer i = -5;
   do buf += buf; while((i = -~i));
   if(bit_length)
   {
       i = 0x800000;
       if(!(bit_length % 24))
           i = 0x80;
       else if((bit_length % 24) == 16)
           i = 0x8000;
   }
   else
       T = 0x80000000;//T is corrupt because of https://jira.secondlife.com/browse/SVC-104
   bit_length += extra_bit_length;

// llOwnerSay(llList2CSV([i,bit_length]));

   b64 = llGetSubString( llDeleteSubString(b64, -4, -1) + 
                         llGetSubString(llIntegerToBase64(T | i), 0, 5) + 
                         buf, 0, (b << 4) / 3) + 
         llIntegerToBase64(bit_length << (6 - ((b % 3) << 1)));
   list x;
   i = 0;
   do
   {
       x = Base64SHA1Compress(b64, H1, H2, H3, H4, H5, i);
       H1 = llList2Integer(x, 0);
       H2 = llList2Integer(x, 1);
       H3 = llList2Integer(x, 2);
       H4 = llList2Integer(x, 3);
       H5 = llList2Integer(x, 4);
   }while(b > (i += 16));
   x = [H1, H2, H3, H4, H5];
   i = -5;
   buf = "";
   do
   {
       T = llList2Integer(x,i);
       bit_length = 32;
       do
           buf += llGetSubString("0123456789abcdef", b = ((T >> (bit_length -= 4)) & 0xF), b);
       while (bit_length);
   }while ((i = -~i));
   return buf;

}


// The Real Thing string Base64_HMAC_SHA1(string B64Key, string B64Data) { // integer H1 = 0x67452301; // integer H2 = 0xefcdab89; // integer H3 = 0x98badcfe; // integer H4 = 0x10325476; // integer H5 = 0xc3d2e1f0;

   integer bit_length = llSubStringIndex(B64Key, "=");
   if (!~bit_length)
   {
       bit_length = llStringLength(B64Key);
   }
   if (bit_length > 86)
   {
       // Use a hash of the key instead as a key
       B64Key = HexToBase64Unpadded(Base64SHA1forHMAC(B64Key, (bit_length*6)&-8, 0, 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0));
       bit_length = 27;
   }
   B64Key = llGetSubString(B64Key, 0, bit_length-1);
   string buf = "AAA";
   integer i = -5;
   do buf += buf; while((i = -~i));
   B64Key = llXorBase64StringsCorrect(llGetSubString(B64Key + buf, 0, 85) + "==", "NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2Ng==");
   list x = Base64SHA1Compress(B64Key, 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0, 0);
   bit_length = (6 * !(B64Data=="") * (llStringLength(B64Data)-4+llStringLength(RemovePadding(llGetSubString(B64Data,-4,-1))))) & -8;
   B64Data = HexToBase64Unpadded(Base64SHA1forHMAC(B64Data, bit_length, 512, llList2Integer(x, 0), llList2Integer(x, 1), llList2Integer(x, 2), llList2Integer(x, 3), llList2Integer(x, 4))) + "=";
   // Xor with Base64(chr(0x36 xor 0x5C) * 64)
   B64Key = llXorBase64StringsCorrect(B64Key, "ampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqampqag==");
   x = Base64SHA1Compress(B64Key, 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0, 0);
   bit_length = 160;
   return Base64SHA1forHMAC(B64Data, bit_length, 512, llList2Integer(x, 0), llList2Integer(x, 1), llList2Integer(x, 2), llList2Integer(x, 3), llList2Integer(x, 4));

}


test_vector_SHA1(string B64Key, string B64Data, string HexHash) {

   llResetTime();
   string hmac = Base64_HMAC_SHA1(B64Key, B64Data);
   if (hmac != HexHash)
   {
       llOwnerSay("HMAC-SHA1 test failed.\nComputed: " + hmac + "\nExpected : " + HexHash);
   }
   else
   {
       llOwnerSay("HMAC-SHA1 test passed in " + (string)llGetTime() + " seconds.");
   }

}


default {

   state_entry()
   {
       // RFC 2202 test vectors:
       test_vector_SHA1(HexToBase64Unpadded("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b") + "=",
                        llStringToBase64("Hi There"),
                        "b617318655057264e28bc0b6fb378c8ef146be00");
       test_vector_SHA1(llStringToBase64("Jefe"),
                        llStringToBase64("what do ya want for nothing?"),
                        "effcdf6ae5eb2fa2d27416d5f184df9c259a7c79");
       test_vector_SHA1("qqqqqqqqqqqqqqqqqqqqqqqqqqo=",
                        "3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d3d0=",
                        "125d7342b9ac11cd91a39af48aa17b4f63f175d3");
       test_vector_SHA1(HexToBase64Unpadded("0102030405060708090a0b0c0d0e0f10111213141516171819")+"==",
                        HexToBase64Unpadded("cdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcd")+"=",
                        "4c9007f4026250c6bc8414f9bf50c86c2d7235da");
       test_vector_SHA1(HexToBase64Unpadded("0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c") + "=",
                        llStringToBase64("Test With Truncation"),
                        "4c1a03424b55e07fe7f27be1d58bb9324a9a5a04");
       string buf = "aaaaa";
       buf += buf;
       buf += buf;
       buf += buf;
       buf += buf;
       buf += buf;
       test_vector_SHA1(HexToBase64Unpadded(buf) + "=",
                        llStringToBase64("Test Using Larger Than Block-Size Key - Hash Key First"),
                        "aa4ae5e15272d00e95705637ce8a3b55ed402112");
       test_vector_SHA1(HexToBase64Unpadded(buf) + "=",
                       llStringToBase64("Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data"),
                       "e8e99d0f45237d786d6bbaa7965c7808bbff1a91");
       // Test vector added by the author
       test_vector_SHA1("", "", "fbdb1d1b18aa6c08324b7d64b71fb76370690e1d");
       // Test vectors added by the author for zero-terminated data strings at different padding positions
       // (generated with an independent program written in PHP):
       test_vector_SHA1("blah", "",         "cf63ad15d4e1d7cdc33cb0084e362afe60d047b1"); // ""
       test_vector_SHA1("blah", "AA==",     "36cda2fc2a348a0b3645a9c135a12118e6f4dcca"); // "\0"
       test_vector_SHA1("blah", "AAA=",     "7b6527796c885a794f695541b4ec1a5af28dec3e"); // "\0\0"
       test_vector_SHA1("blah", "AAAA",     "d79915ec627764b7092ec66036fcaf94e4d94091"); // "\0\0\0"
       test_vector_SHA1("blah", "MQA=",     "9fa63e8684813ca6f601e7e082fd989c72295019"); // "1\0"
       test_vector_SHA1("blah", "MQAA",     "0d1ad14b1c4da14d5fca5b2e3486a7df2ef5fa12"); // "1\0\0"
       test_vector_SHA1("blah", "MQAAAA==", "29ba52e7d932fdb2854cf52f75dea30aa0773025"); // "1\0\0\0"
       test_vector_SHA1("blah", "MTIA",     "ee65d68cdba172a95b7cc1640573bfa4f10fcf9d"); // "12\0"
       test_vector_SHA1("blah", "MTIAAA==", "4908fdece951bc779690565b54960a5e93119d56"); // "12\0\0"
       test_vector_SHA1("blah", "MTIAAAA=", "3213b2e563af1d5c04159bfcee0ee81124aaefb7"); // "12\0\0\0"
       test_vector_SHA1("blah", "MTIzAA==", "f3967f44b64b8a32b3d0c9cfe514e580aca6869d"); // "123\0"
       test_vector_SHA1("blah", "MTIzAAA=", "e509dfb925f1bd533216ba1f44d3ba1a998d078c"); // "123\0\0"
       test_vector_SHA1("blah", "MTIzAAAA", "06476a68a5c2c6cfc5c595b83dcc672e910a3e3e"); // "123\0\0\0"
       llOwnerSay("End of tests.");
   }

} </lsl>