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