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I need to convert string in UTF-8 to byte array in 1251 codepage in JavaScript. Google says nothing useful. Help :)
EDIT: What is it for.
We have server and client. Server has userpasswords hased with SHA512 and 1251 codepage. Client (web browser) has to hash passwords (provided by user in plain text) with SHA512 and transmit it to the server. The problem is: browser works in UTF-8 encoding, and of course SHA512 in UFT-8 is not the same as SHA512 in 1251. Any Ideas?
EDIT2: got it! :)
//utf8 to 1251 converter (1 byte format, RU/EN support only + any other symbols) by drgluck
function utf8_decode (aa) {
var bb = '', c = 0;
for (var i = 0; i < aa.length; i++) {
c = aa.charCodeAt(i);
if (c > 127) {
if (c > 1024) {
if (c == 1025) {
c = 1016;
} else if (c == 1105) {
c = 1032;
}
bb += String.fromCharCode(c - 848);
}
} else {
bb += aa.charAt(i);
}
}
return bb;
}
Usage with SHA512 implementation by Paul Johnston (http://pajhome.org.uk/crypt/md5/sha512.html)
...
return rstr2hex(rstr_sha512(utf8_decode(input)));
727
Most JavaScript engines use UTF-16 encoding, so let's detail into UTF-16. UTF-16 (the long name: 16-bit Unicode Transformation Format) is a variable-length encoding: Code points from BMP are encoded using a single code unit of 16-bit. Code points from astral planes are encoded using two code units of 16-bit each.
UTF-8 is an encoding system for Unicode. It can translate any Unicode character to a matching unique binary string, and can also translate the binary string back to a Unicode character. This is the meaning of “UTF”, or “Unicode Transformation Format.”
Encoding in Node is extremely confusing, and difficult to get right. It helps, though, when you realize that Javascript string types will always be encoded as UTF-16, and most of the other places strings in RAM interact with sockets, files, or byte arrays, the string gets re-encoded as UTF-8.
UTF-8 is the universal code page for internationalization and is able to encode the entire Unicode character set. It is used pervasively on the web, and is the default for *nix-based platforms.
This encodes the Unicode codepoints in JavaScript to windows-1251:
var DMap = {0: 0, 1: 1, 2: 2, 3: 3, 4: 4, 5: 5, 6: 6, 7: 7, 8: 8, 9: 9, 10: 10, 11: 11, 12: 12, 13: 13, 14: 14, 15: 15, 16: 16, 17: 17, 18: 18, 19: 19, 20: 20, 21: 21, 22: 22, 23: 23, 24: 24, 25: 25, 26: 26, 27: 27, 28: 28, 29: 29, 30: 30, 31: 31, 32: 32, 33: 33, 34: 34, 35: 35, 36: 36, 37: 37, 38: 38, 39: 39, 40: 40, 41: 41, 42: 42, 43: 43, 44: 44, 45: 45, 46: 46, 47: 47, 48: 48, 49: 49, 50: 50, 51: 51, 52: 52, 53: 53, 54: 54, 55: 55, 56: 56, 57: 57, 58: 58, 59: 59, 60: 60, 61: 61, 62: 62, 63: 63, 64: 64, 65: 65, 66: 66, 67: 67, 68: 68, 69: 69, 70: 70, 71: 71, 72: 72, 73: 73, 74: 74, 75: 75, 76: 76, 77: 77, 78: 78, 79: 79, 80: 80, 81: 81, 82: 82, 83: 83, 84: 84, 85: 85, 86: 86, 87: 87, 88: 88, 89: 89, 90: 90, 91: 91, 92: 92, 93: 93, 94: 94, 95: 95, 96: 96, 97: 97, 98: 98, 99: 99, 100: 100, 101: 101, 102: 102, 103: 103, 104: 104, 105: 105, 106: 106, 107: 107, 108: 108, 109: 109, 110: 110, 111: 111, 112: 112, 113: 113, 114: 114, 115: 115, 116: 116, 117: 117, 118: 118, 119: 119, 120: 120, 121: 121, 122: 122, 123: 123, 124: 124, 125: 125, 126: 126, 127: 127, 1027: 129, 8225: 135, 1046: 198, 8222: 132, 1047: 199, 1168: 165, 1048: 200, 1113: 154, 1049: 201, 1045: 197, 1050: 202, 1028: 170, 160: 160, 1040: 192, 1051: 203, 164: 164, 166: 166, 167: 167, 169: 169, 171: 171, 172: 172, 173: 173, 174: 174, 1053: 205, 176: 176, 177: 177, 1114: 156, 181: 181, 182: 182, 183: 183, 8221: 148, 187: 187, 1029: 189, 1056: 208, 1057: 209, 1058: 210, 8364: 136, 1112: 188, 1115: 158, 1059: 211, 1060: 212, 1030: 178, 1061: 213, 1062: 214, 1063: 215, 1116: 157, 1064: 216, 1065: 217, 1031: 175, 1066: 218, 1067: 219, 1068: 220, 1069: 221, 1070: 222, 1032: 163, 8226: 149, 1071: 223, 1072: 224, 8482: 153, 1073: 225, 8240: 137, 1118: 162, 1074: 226, 1110: 179, 8230: 133, 1075: 227, 1033: 138, 1076: 228, 1077: 229, 8211: 150, 1078: 230, 1119: 159, 1079: 231, 1042: 194, 1080: 232, 1034: 140, 1025: 168, 1081: 233, 1082: 234, 8212: 151, 1083: 235, 1169: 180, 1084: 236, 1052: 204, 1085: 237, 1035: 142, 1086: 238, 1087: 239, 1088: 240, 1089: 241, 1090: 242, 1036: 141, 1041: 193, 1091: 243, 1092: 244, 8224: 134, 1093: 245, 8470: 185, 1094: 246, 1054: 206, 1095: 247, 1096: 248, 8249: 139, 1097: 249, 1098: 250, 1044: 196, 1099: 251, 1111: 191, 1055: 207, 1100: 252, 1038: 161, 8220: 147, 1101: 253, 8250: 155, 1102: 254, 8216: 145, 1103: 255, 1043: 195, 1105: 184, 1039: 143, 1026: 128, 1106: 144, 8218: 130, 1107: 131, 8217: 146, 1108: 186, 1109: 190}
function UnicodeToWin1251(s) {
var L = []
for (var i=0; i<s.length; i++) {
var ord = s.charCodeAt(i)
if (!(ord in DMap))
throw "Character "+s.charAt(i)+" isn't supported by win1251!"
L.push(String.fromCharCode(DMap[ord]))
}
return L.join('')
}
JavaScript stores each character as raw Unicode codepoints, so the above should work before getting the hash using SHA512.
122
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