[5145] | 1 | /** |
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| 2 | * |
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| 3 | * Base64 encode / decode |
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| 4 | * http://www.webtoolkit.info/ |
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| 5 | * |
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| 6 | **/ |
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| 7 | |
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| 8 | var Base64 = { |
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| 9 | |
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| 10 | // private property |
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| 11 | _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", |
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| 12 | |
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| 13 | // public method for encoding |
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| 14 | encode : function (input) { |
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| 15 | var output = ""; |
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| 16 | var chr1, chr2, chr3, enc1, enc2, enc3, enc4; |
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| 17 | var i = 0; |
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| 18 | |
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| 19 | input = Base64._utf8_encode(input); |
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| 20 | |
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| 21 | while (i < input.length) { |
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| 22 | |
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| 23 | chr1 = input.charCodeAt(i++); |
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| 24 | chr2 = input.charCodeAt(i++); |
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| 25 | chr3 = input.charCodeAt(i++); |
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| 26 | |
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| 27 | enc1 = chr1 >> 2; |
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| 28 | enc2 = ((chr1 & 3) << 4) | (chr2 >> 4); |
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| 29 | enc3 = ((chr2 & 15) << 2) | (chr3 >> 6); |
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| 30 | enc4 = chr3 & 63; |
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| 31 | |
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| 32 | if (isNaN(chr2)) { |
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| 33 | enc3 = enc4 = 64; |
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| 34 | } else if (isNaN(chr3)) { |
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| 35 | enc4 = 64; |
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| 36 | } |
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| 37 | |
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| 38 | output = output + |
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| 39 | this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + |
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| 40 | this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4); |
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| 41 | |
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| 42 | } |
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| 43 | |
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| 44 | return output; |
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| 45 | }, |
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| 46 | |
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| 47 | // public method for decoding |
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| 48 | decode : function (input) { |
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| 49 | var output = ""; |
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| 50 | var chr1, chr2, chr3; |
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| 51 | var enc1, enc2, enc3, enc4; |
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| 52 | var i = 0; |
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| 53 | |
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| 54 | input = input.replace(/[^A-Za-z0-9\+\/\=]/g, ""); |
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| 55 | |
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| 56 | while (i < input.length) { |
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| 57 | |
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| 58 | enc1 = this._keyStr.indexOf(input.charAt(i++)); |
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| 59 | enc2 = this._keyStr.indexOf(input.charAt(i++)); |
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| 60 | enc3 = this._keyStr.indexOf(input.charAt(i++)); |
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| 61 | enc4 = this._keyStr.indexOf(input.charAt(i++)); |
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| 62 | |
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| 63 | chr1 = (enc1 << 2) | (enc2 >> 4); |
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| 64 | chr2 = ((enc2 & 15) << 4) | (enc3 >> 2); |
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| 65 | chr3 = ((enc3 & 3) << 6) | enc4; |
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| 66 | |
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| 67 | output = output + String.fromCharCode(chr1); |
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| 68 | |
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| 69 | if (enc3 != 64) { |
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| 70 | output = output + String.fromCharCode(chr2); |
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| 71 | } |
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| 72 | if (enc4 != 64) { |
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| 73 | output = output + String.fromCharCode(chr3); |
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| 74 | } |
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| 75 | |
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| 76 | } |
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| 77 | |
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| 78 | output = Base64._utf8_decode(output); |
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| 79 | |
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| 80 | return output; |
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| 81 | |
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| 82 | }, |
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| 83 | |
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| 84 | // private method for UTF-8 encoding |
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| 85 | _utf8_encode : function (string) { |
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| 86 | string = string.replace(/\r\n/g,"\n"); |
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| 87 | var utftext = ""; |
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| 88 | |
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| 89 | for (var n = 0; n < string.length; n++) { |
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| 90 | |
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| 91 | var c = string.charCodeAt(n); |
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| 92 | |
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| 93 | if (c < 128) { |
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| 94 | utftext += String.fromCharCode(c); |
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| 95 | } |
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| 96 | else if((c > 127) && (c < 2048)) { |
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| 97 | utftext += String.fromCharCode((c >> 6) | 192); |
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| 98 | utftext += String.fromCharCode((c & 63) | 128); |
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| 99 | } |
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| 100 | else { |
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| 101 | utftext += String.fromCharCode((c >> 12) | 224); |
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| 102 | utftext += String.fromCharCode(((c >> 6) & 63) | 128); |
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| 103 | utftext += String.fromCharCode((c & 63) | 128); |
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| 104 | } |
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| 105 | |
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| 106 | } |
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| 107 | |
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| 108 | return utftext; |
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| 109 | }, |
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| 110 | |
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| 111 | // private method for UTF-8 decoding |
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| 112 | _utf8_decode : function (utftext) { |
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| 113 | var string = ""; |
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| 114 | var i = 0; |
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| 115 | var c = c1 = c2 = 0; |
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| 116 | |
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| 117 | while ( i < utftext.length ) { |
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| 118 | |
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| 119 | c = utftext.charCodeAt(i); |
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| 120 | |
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| 121 | if (c < 128) { |
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| 122 | string += String.fromCharCode(c); |
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| 123 | i++; |
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| 124 | } |
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| 125 | else if((c > 191) && (c < 224)) { |
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| 126 | c2 = utftext.charCodeAt(i+1); |
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| 127 | string += String.fromCharCode(((c & 31) << 6) | (c2 & 63)); |
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| 128 | i += 2; |
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| 129 | } |
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| 130 | else { |
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| 131 | c2 = utftext.charCodeAt(i+1); |
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| 132 | c3 = utftext.charCodeAt(i+2); |
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| 133 | string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63)); |
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| 134 | i += 3; |
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| 135 | } |
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| 136 | |
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| 137 | } |
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| 138 | |
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| 139 | return string; |
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| 140 | } |
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| 141 | |
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| 142 | } |
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