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comparison: recaptchalib.php

recaptchalib.php

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1 <?php
2 /*
3 * This is a PHP library that handles calling reCAPTCHA.
4 * - Documentation and latest version
5 * http://recaptcha.net/plugins/php/
6 * - Get a reCAPTCHA API Key
7 * http://recaptcha.net/api/getkey
8 * - Discussion group
9 * http://groups.google.com/group/recaptcha
10 *
11 * Copyright (c) 2007 reCAPTCHA -- http://recaptcha.net
12 * AUTHORS:
13 * Mike Crawford
14 * Ben Maurer
15 *
16 * Permission is hereby granted, free of charge, to any person obtaining a copy
17 * of this software and associated documentation files (the "Software"), to deal
18 * in the Software without restriction, including without limitation the rights
19 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
20 * copies of the Software, and to permit persons to whom the Software is
21 * furnished to do so, subject to the following conditions:
22 *
23 * The above copyright notice and this permission notice shall be included in
24 * all copies or substantial portions of the Software.
25 *
26 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
27 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
28 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
29 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
30 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
31 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
32 * THE SOFTWARE.
33 */
34
35 /**
36 * The reCAPTCHA server URL's
37 */
38 define("RECAPTCHA_API_SERVER", "http://api.recaptcha.net");
39 define("RECAPTCHA_API_SECURE_SERVER", "https://api-secure.recaptcha.net");
40 define("RECAPTCHA_VERIFY_SERVER", "api-verify.recaptcha.net");
41
42 /**
43 * Encodes the given data into a query string format
44 * @param $data - array of string elements to be encoded
45 * @return string - encoded request
46 */
47 function _recaptcha_qsencode ($data) {
48 $req = "";
49 foreach ( $data as $key => $value )
50 $req .= $key . '=' . urlencode( stripslashes($value) ) . '&';
51
52 // Cut the last '&'
53 $req=substr($req,0,strlen($req)-1);
54 return $req;
55 }
56
57
58
59 /**
60 * Submits an HTTP POST to a reCAPTCHA server
61 * @param string $host
62 * @param string $path
63 * @param array $data
64 * @param int port
65 * @return array response
66 */
67 function _recaptcha_http_post($host, $path, $data, $port = 80) {
68
69 $req = _recaptcha_qsencode ($data);
70
71 $http_request = "POST $path HTTP/1.0\r\n";
72 $http_request .= "Host: $host\r\n";
73 $http_request .= "Content-Type: application/x-www-form-urlencoded;\r\n";
74 $http_request .= "Content-Length: " . strlen($req) . "\r\n";
75 $http_request .= "User-Agent: reCAPTCHA/PHP\r\n";
76 $http_request .= "\r\n";
77 $http_request .= $req;
78
79 $response = '';
80 if( false == ( $fs = @fsockopen($host, $port, $errno, $errstr, 10) ) ) {
81 die ('Could not open socket');
82 }
83
84 fwrite($fs, $http_request);
85
86 while ( !feof($fs) )
87 $response .= fgets($fs, 1160); // One TCP-IP packet
88 fclose($fs);
89 $response = explode("\r\n\r\n", $response, 2);
90
91 return $response;
92 }
93
94
95
96 /**
97 * Gets the challenge HTML (javascript and non-javascript version).
98 * This is called from the browser, and the resulting reCAPTCHA HTML widget
99 * is embedded within the HTML form it was called from.
100 * @param string $pubkey A public key for reCAPTCHA
101 * @param string $error The error given by reCAPTCHA (optional, default is null)
102 * @param boolean $use_ssl Should the request be made over ssl? (optional, default is false)
103
104 * @return string - The HTML to be embedded in the user's form.
105 */
106 function recaptcha_get_html ($pubkey, $error = null, $use_ssl = false)
107 {
108 if ($pubkey == null || $pubkey == '') {
109 die ("To use reCAPTCHA you must get an API key from <a href='http://recaptcha.net/api/getkey'>http://recaptcha.net/api/getkey</a>");
110 }
111
112 if ($use_ssl) {
113 $server = RECAPTCHA_API_SECURE_SERVER;
114 } else {
115 $server = RECAPTCHA_API_SERVER;
116 }
117
118 $errorpart = "";
119 if ($error) {
120 $errorpart = "&amp;error=" . $error;
121 }
122 return '<script type="text/javascript" src="'. $server . '/challenge?k=' . $pubkey . $errorpart . '"></script>
123
124 <noscript>
125 <iframe src="'. $server . '/noscript?k=' . $pubkey . $errorpart . '" height="300" width="500" frameborder="0"></iframe><br/>
126 <textarea name="recaptcha_challenge_field" rows="3" cols="40"></textarea>
127 <input type="hidden" name="recaptcha_response_field" value="manual_challenge"/>
128 </noscript>';
129 }
130
131
132
133
134 /**
135 * A ReCaptchaResponse is returned from recaptcha_check_answer()
136 */
137 class ReCaptchaResponse {
138 var $is_valid;
139 var $error;
140 }
141
142
143 /**
144 * Calls an HTTP POST function to verify if the user's guess was correct
145 * @param string $privkey
146 * @param string $remoteip
147 * @param string $challenge
148 * @param string $response
149 * @param array $extra_params an array of extra variables to post to the server
150 * @return ReCaptchaResponse
151 */
152 function recaptcha_check_answer ($privkey, $remoteip, $challenge, $response, $extra_params = array())
153 {
154 if ($privkey == null || $privkey == '') {
155 die ("To use reCAPTCHA you must get an API key from <a href='http://recaptcha.net/api/getkey'>http://recaptcha.net/api/getkey</a>");
156 }
157
158 if ($remoteip == null || $remoteip == '') {
159 die ("For security reasons, you must pass the remote ip to reCAPTCHA");
160 }
161
162
163
164 //discard spam submissions
165 if ($challenge == null || strlen($challenge) == 0 || $response == null || strlen($response) == 0) {
166 $recaptcha_response = new ReCaptchaResponse();
167 $recaptcha_response->is_valid = false;
168 $recaptcha_response->error = 'incorrect-captcha-sol';
169 return $recaptcha_response;
170 }
171
172 $response = _recaptcha_http_post (RECAPTCHA_VERIFY_SERVER, "/verify",
173 array (
174 'privatekey' => $privkey,
175 'remoteip' => $remoteip,
176 'challenge' => $challenge,
177 'response' => $response
178 ) + $extra_params
179 );
180
181 $answers = explode ("\n", $response [1]);
182 $recaptcha_response = new ReCaptchaResponse();
183
184 if (trim ($answers [0]) == 'true') {
185 $recaptcha_response->is_valid = true;
186 }
187 else {
188 $recaptcha_response->is_valid = false;
189 $recaptcha_response->error = $answers [1];
190 }
191 return $recaptcha_response;
192
193 }
194
195 /**
196 * gets a URL where the user can sign up for reCAPTCHA. If your application
197 * has a configuration page where you enter a key, you should provide a link
198 * using this function.
199 * @param string $domain The domain where the page is hosted
200 * @param string $appname The name of your application
201 */
202 function recaptcha_get_signup_url ($domain = null, $appname = null) {
203 return "http://recaptcha.net/api/getkey?" . _recaptcha_qsencode (array ('domain' => $domain, 'app' => $appname));
204 }
205
206 function _recaptcha_aes_pad($val) {
207 $block_size = 16;
208 $numpad = $block_size - (strlen ($val) % $block_size);
209 return str_pad($val, strlen ($val) + $numpad, chr($numpad));
210 }
211
212 /* Mailhide related code */
213
214 function _recaptcha_aes_encrypt($val,$ky) {
215 if (! function_exists ("mcrypt_encrypt")) {
216 die ("To use reCAPTCHA Mailhide, you need to have the mcrypt php module installed.");
217 }
218 $mode=MCRYPT_MODE_CBC;
219 $enc=MCRYPT_RIJNDAEL_128;
220 $val=_recaptcha_aes_pad($val);
221 return mcrypt_encrypt($enc, $ky, $val, $mode, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");
222 }
223
224
225 function _recaptcha_mailhide_urlbase64 ($x) {
226 return strtr(base64_encode ($x), '+/', '-_');
227 }
228
229 /* gets the reCAPTCHA Mailhide url for a given email, public key and private key */
230 function recaptcha_mailhide_url($pubkey, $privkey, $email) {
231 if ($pubkey == '' || $pubkey == null || $privkey == "" || $privkey == null) {
232 die ("To use reCAPTCHA Mailhide, you have to sign up for a public and private key, " .
233 "you can do so at <a href='http://mailhide.recaptcha.net/apikey'>http://mailhide.recaptcha.net/apikey</a>");
234 }
235
236
237 $ky = pack('H*', $privkey);
238 $cryptmail = _recaptcha_aes_encrypt ($email, $ky);
239
240 return "http://mailhide.recaptcha.net/d?k=" . $pubkey . "&c=" . _recaptcha_mailhide_urlbase64 ($cryptmail);
241 }
242
243 /**
244 * gets the parts of the email to expose to the user.
245 * eg, given johndoe@example,com return ["john", "example.com"].
246 * the email is then displayed as john...@example.com
247 */
248 function _recaptcha_mailhide_email_parts ($email) {
249 $arr = preg_split("/@/", $email );
250
251 if (strlen ($arr[0]) <= 4) {
252 $arr[0] = substr ($arr[0], 0, 1);
253 } else if (strlen ($arr[0]) <= 6) {
254 $arr[0] = substr ($arr[0], 0, 3);
255 } else {
256 $arr[0] = substr ($arr[0], 0, 4);
257 }
258 return $arr;
259 }
260
261 /**
262 * Gets html to display an email address given a public an private key.
263 * to get a key, go to:
264 *
265 * http://mailhide.recaptcha.net/apikey
266 */
267 function recaptcha_mailhide_html($pubkey, $privkey, $email) {
268 $emailparts = _recaptcha_mailhide_email_parts ($email);
269 $url = recaptcha_mailhide_url ($pubkey, $privkey, $email);
270
271 return htmlentities($emailparts[0]) . "<a href='" . htmlentities ($url) .
272 "' onclick=\"window.open('" . htmlentities ($url) . "', '', 'toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=0,width=500,height=300'); return false;\" title=\"Reveal this e-mail address\">...</a>@" . htmlentities ($emailparts [1]);
273
274 }
275
276
277 ?>

Mercurial Repository: xmpp-web-registration

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