1 | <?php |
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18 | class Xss |
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19 | { |
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20 | |||
21 | private $_xss_found = null; |
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22 | private $neverAllowed; |
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23 | private $exploded; |
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24 | private $string; |
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25 | private $attributes; |
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26 | private $javascript; |
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27 | private $html; |
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28 | private $utf7; |
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29 | private $utf8; |
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30 | private $strings; |
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31 | private $system; |
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32 | |||
33 | |||
34 | 6 | function __construct() |
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38 | |||
39 | 6 | function init() |
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56 | |||
57 | |||
58 | function setString($str) |
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62 | |||
63 | public function cleanArray($array) |
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67 | |||
68 | /** |
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69 | * @param $str |
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70 | * @return array|mixed |
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71 | */ |
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72 | 6 | public function clean($str) |
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89 | |||
90 | 6 | private function process($str, $old_str_backup) |
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106 | |||
107 | /** |
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108 | * @param StringResource $str |
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109 | * |
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110 | * @return mixed |
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111 | */ |
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112 | 6 | private function _do($str) |
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113 | { |
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114 | 6 | $str = (string)$str; |
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115 | 6 | $strInt = (int)$str; |
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116 | 6 | $strFloat = (float)$str; |
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117 | 6 | if (!$str || (string)$strInt === $str || (string)$strFloat === $str) { |
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118 | |||
119 | // no xss found |
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120 | 6 | if ($this->_xss_found !== true) { |
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121 | 6 | $this->_xss_found = false; |
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122 | } |
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123 | |||
124 | 6 | return $str; |
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125 | } |
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126 | |||
127 | // remove the BOM from UTF-8 / UTF-16 / UTF-32 strings |
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128 | 6 | $str = $this->utf8->remove_bom($str); |
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129 | |||
130 | // replace the diamond question mark (�) and invalid-UTF8 chars |
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131 | 6 | $str = $this->utf8->replace_diamond_question_mark($str, ''); |
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132 | |||
133 | // replace invisible characters with one single space |
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134 | 6 | $str = $this->utf8->remove_invisible_characters($str, true, ' '); |
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135 | |||
136 | 6 | $str = $this->utf8->normalize_whitespace($str); |
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137 | 6 | $str = $this->strings->replace($str); |
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138 | |||
139 | // decode UTF-7 characters |
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140 | 6 | $str = $this->utf7->repack($str); |
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141 | |||
142 | // decode the string |
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143 | 6 | $str = $this->decodeString($str); // RW Partly DONE |
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144 | |||
145 | // backup the string (for later comparision) |
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146 | 6 | $str_backup = $str; |
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147 | |||
148 | // remove strings that are never allowed |
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149 | 6 | $str = $this->neverAllowed->doNeverAllowed($str); //RW DONE |
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150 | |||
151 | // corrects words before the browser will do it |
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152 | 6 | $str = $this->exploded->compactExplodedString($str); //RW DONE |
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153 | |||
154 | // remove disallowed javascript calls in links, images etc. |
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155 | 6 | $str = $this->javascript->removeDisallowedJavascript($str); |
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156 | |||
157 | // remove evil attributes such as style, onclick and xmlns |
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158 | 6 | $str = $this->attributes->removeEvilAttributes($str); |
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159 | |||
160 | // sanitize naughty JavaScript elements |
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161 | 6 | $str = $this->javascript->naughtyJavascript($str); |
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162 | |||
163 | // sanitize naughty HTML elements |
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164 | 6 | $str = $this->html->naughtyHtml($str); |
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165 | |||
166 | // final clean up |
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167 | // |
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168 | // -> This adds a bit of extra precaution in case something got through the above filters. |
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169 | 6 | $str = $this->neverAllowed->doNeverAllowedAfterwards($str); |
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170 | |||
171 | // check for xss |
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172 | 6 | if ($this->_xss_found !== true) { |
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173 | 6 | $this->_xss_found = !($str_backup === $str); |
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174 | } |
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175 | |||
176 | 6 | return $str; |
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177 | } |
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178 | |||
179 | 6 | public function decodeString($str) |
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180 | { |
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181 | // init |
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182 | 6 | $regExForHtmlTags = '/<\p{L}+.*+/us'; |
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183 | |||
184 | 6 | if (strpos($str, '<') !== false && preg_match($regExForHtmlTags, $str, $matches) === 1) { |
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185 | 6 | $str = (string)preg_replace_callback( |
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186 | 6 | $regExForHtmlTags, |
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187 | function ($matches) { |
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188 | 6 | return $this->decodeEntity($matches); |
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189 | 6 | }, |
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190 | 6 | $str |
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191 | ); |
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192 | } else { |
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193 | 6 | $str = $this->utf8->rawurldecode($str); |
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194 | } |
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195 | |||
196 | 6 | return $str; |
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197 | } |
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198 | |||
199 | 6 | private function decodeEntity(array $match) |
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200 | { |
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201 | // init |
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202 | 6 | $str = $match[0]; |
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203 | |||
204 | // protect GET variables without XSS in URLs |
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205 | 6 | if (preg_match_all("/[\?|&]?[\\p{L}0-9_\-\[\]]+\s*=\s*(?<wrapped>\"|\042|'|\047)(?<attr>[^\\1]*?)\\g{wrapped}/ui", $str, $matches)) { |
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206 | 6 | if (isset($matches['attr'])) { |
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207 | 6 | foreach ($matches['attr'] as $matchInner) { |
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208 | 6 | $tmpAntiXss = clone $this; |
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209 | 6 | $urlPartClean = $tmpAntiXss->clean($matchInner); |
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210 | |||
211 | 6 | if ($tmpAntiXss->isXssFound() === true) { |
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212 | 6 | $this->_xss_found = true; |
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213 | 6 | $str = \str_replace($matchInner, $this->utf8->rawurldecode($urlPartClean), $str); |
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214 | } |
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215 | } |
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216 | } |
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217 | } else { |
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218 | 6 | $str = $this->_entity_decode($this->utf8->rawurldecode($str)); |
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219 | } |
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220 | |||
221 | 6 | return $str; |
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222 | } |
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223 | |||
224 | /** |
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225 | * @return null |
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226 | */ |
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227 | 6 | public function isXssFound() |
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231 | |||
232 | /** |
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233 | * Entity-decoding. |
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234 | * |
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235 | * @param StringResource $str |
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236 | * |
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237 | * @return StringResource |
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238 | */ |
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239 | 6 | private function _entity_decode($str) |
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240 | { |
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241 | 6 | static $HTML_ENTITIES_CACHE; |
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242 | |||
243 | 6 | $flags = ENT_QUOTES | ENT_HTML5 | ENT_DISALLOWED | ENT_SUBSTITUTE; |
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244 | |||
245 | // decode |
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246 | 6 | $str = html_entity_decode($str, $flags); |
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247 | |||
248 | |||
249 | // decode-again, for e.g. HHVM or miss configured applications ... |
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250 | 6 | if (preg_match_all('/(?<html_entity>&[A-Za-z]{2,}[;]{0})/', $str, $matches)) { |
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251 | if ($HTML_ENTITIES_CACHE === null) { |
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252 | |||
253 | // links: |
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254 | // - http://dev.w3.org/html5/html-author/charref |
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255 | // - http://www.w3schools.com/charsets/ref_html_entities_n.asp |
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256 | $entitiesSecurity = [ |
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257 | '�' => '', |
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258 | '�' => '', |
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259 | '' => '', |
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260 | '' => '', |
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261 | '>⃒' => '', |
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262 | '' => '', |
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263 | '' => '', |
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264 | '­' => '', |
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265 | '­' => '', |
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266 | '­' => '', |
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267 | ':' => ':', |
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268 | ':' => ':', |
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269 | ':' => ':', |
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270 | '(' => '(', |
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271 | '(' => '(', |
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272 | '(' => '(', |
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273 | ')' => ')', |
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274 | ')' => ')', |
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275 | ')' => ')', |
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276 | '?' => '?', |
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277 | '?' => '?', |
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278 | '?' => '?', |
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279 | '/' => '/', |
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280 | '/' => '/', |
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281 | '/' => '/', |
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282 | ''' => '\'', |
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283 | ''' => '\'', |
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284 | ''' => '\'', |
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285 | ''' => '\'', |
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286 | ''' => '\'', |
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287 | '\' => '\'', |
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288 | '\' => '\\', |
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289 | '\' => '\\', |
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290 | ',' => ',', |
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291 | ',' => ',', |
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292 | ',' => ',', |
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293 | '.' => '.', |
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294 | '.' => '.', |
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295 | '"' => '"', |
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296 | '"' => '"', |
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297 | '"' => '"', |
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298 | '"' => '"', |
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299 | '`' => '`', |
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300 | '`' => '`', |
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301 | '`' => '`', |
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302 | '`' => '`', |
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303 | '.' => '.', |
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304 | '=' => '=', |
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305 | '=' => '=', |
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306 | '=' => '=', |
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307 | '&newline;' => "\n", |
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308 | '
' => "\n", |
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309 | ' ' => "\n", |
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310 | '&tab;' => "\t", |
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311 | '	' => "\t", |
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312 | '	' => "\t", |
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313 | ]; |
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314 | |||
315 | $HTML_ENTITIES_CACHE = \array_merge( |
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316 | $entitiesSecurity, |
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317 | \array_flip(\get_html_translation_table(HTML_ENTITIES, $flags)), |
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318 | \array_flip($this->_get_data('entities_fallback')) |
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319 | ); |
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320 | } |
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321 | |||
322 | $search = []; |
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323 | $replace = []; |
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324 | foreach ($matches['html_entity'] as $match) { |
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325 | $match .= ';'; |
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326 | if (isset($HTML_ENTITIES_CACHE[$match])) { |
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327 | $search[$match] = $match; |
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328 | $replace[$match] = $HTML_ENTITIES_CACHE[$match]; |
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329 | } |
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330 | } |
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331 | |||
332 | if (\count($replace) > 0) { |
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333 | $str = \str_replace($search, $replace, $str); |
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334 | } |
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335 | } |
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336 | |||
337 | 6 | return $str; |
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338 | } |
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339 | |||
340 | private function _get_data($file) |
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345 | |||
346 | public function cleanString($str) |
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350 | |||
351 | /** |
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352 | * @param $str |
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353 | * @return array|mixed |
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354 | */ |
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355 | 3 | public function cleanUrl($str) |
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377 | } |
This check marks property names that have not been written in camelCase.
In camelCase names are written without any punctuation, the start of each new word being marked by a capital letter. Thus the name database connection string becomes
databaseConnectionString
.