math-fallback.php
| 1 | <?php |
| 2 | |
| 3 | if ( ! class_exists( 'Jetpack_Protect_Math_Authenticate' ) ) { |
| 4 | /* |
| 5 | * The math captcha fallback if we can't talk to the Protect API |
| 6 | */ |
| 7 | class Jetpack_Protect_Math_Authenticate { |
| 8 | |
| 9 | static $loaded; |
| 10 | |
| 11 | function __construct() { |
| 12 | |
| 13 | if ( self::$loaded ) { |
| 14 | return; |
| 15 | } |
| 16 | |
| 17 | self::$loaded = 1; |
| 18 | |
| 19 | add_action( 'login_form', array( $this, 'math_form' ) ); |
| 20 | |
| 21 | if( isset( $_POST[ 'jetpack_protect_process_math_form' ] ) ) { |
| 22 | add_action( 'init', array( $this, 'process_generate_math_page' ) ); |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | /** |
| 27 | * Verifies that a user answered the math problem correctly while logging in. |
| 28 | * |
| 29 | * @return bool Returns true if the math is correct |
| 30 | * @throws Error if insuffient $_POST variables are present. |
| 31 | * @throws Error message if the math is wrong |
| 32 | */ |
| 33 | static function math_authenticate() { |
| 34 | $salt = get_site_option( 'jetpack_protect_key' ) . get_site_option( 'admin_email' ); |
| 35 | $ans = isset( $_POST['jetpack_protect_num'] ) ? (int) $_POST['jetpack_protect_num'] : '' ; |
| 36 | $salted_ans = sha1( $salt . $ans ); |
| 37 | $correct_ans = isset( $_POST[ 'jetpack_protect_answer' ] ) ? $_POST[ 'jetpack_protect_answer' ] : '' ; |
| 38 | |
| 39 | if( isset( $_COOKIE[ 'jpp_math_pass' ] ) ) { |
| 40 | $jetpack_protect = Jetpack_Protect_Module::instance(); |
| 41 | $transient = $jetpack_protect->get_transient( 'jpp_math_pass_' . $_COOKIE[ 'jpp_math_pass' ] ); |
| 42 | |
| 43 | if( !$transient || $transient < 1 ) { |
| 44 | Jetpack_Protect_Math_Authenticate::generate_math_page(); |
| 45 | } |
| 46 | return true; |
| 47 | } |
| 48 | |
| 49 | if ( ! $correct_ans || !$_POST['jetpack_protect_num'] ) { |
| 50 | Jetpack_Protect_Math_Authenticate::generate_math_page(); |
| 51 | } elseif ( $salted_ans != $correct_ans ) { |
| 52 | wp_die( |
| 53 | __( '<strong>You failed to correctly answer the math problem.</strong> This is used to combat spam when the Protect API is unavailable. Please use your browser\'s back button to return to the login form, press the "refresh" button to generate a new math problem, and try to log in again.', 'jetpack' ), |
| 54 | '', |
| 55 | array ( 'response' => 401 ) |
| 56 | ); |
| 57 | } else { |
| 58 | return true; |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Creates an interim page to collect answers to a math captcha |
| 64 | * |
| 65 | * @return none, execution stopped |
| 66 | */ |
| 67 | static function generate_math_page( $error = false ) { |
| 68 | $salt = get_site_option( 'jetpack_protect_key' ) . get_site_option( 'admin_email' ); |
| 69 | $num1 = rand( 0, 10 ); |
| 70 | $num2 = rand( 1, 10 ); |
| 71 | $sum = $num1 + $num2; |
| 72 | $ans = sha1( $salt . $sum ); |
| 73 | ob_start(); |
| 74 | ?> |
| 75 | <h2><?php _e( 'Please solve this math problem to prove that you are not a bot. Once you solve it, you will need to log in again.', 'jetpack' ); ?></h2> |
| 76 | <?php if ($error): ?> |
| 77 | <h3><?php _e( 'Your answer was incorrect, please try again.', 'jetpack' ); ?></h3> |
| 78 | <?php endif ?> |
| 79 | |
| 80 | <form action="<?php echo wp_login_url(); ?>" method="post" accept-charset="utf-8"> |
| 81 | <?php Jetpack_Protect_Math_Authenticate::math_form(); ?> |
| 82 | <input type="hidden" name="jetpack_protect_process_math_form" value="1" id="jetpack_protect_process_math_form" /> |
| 83 | <p><input type="submit" value="<?php esc_html_e( 'Continue →', 'jetpack' ); ?>"></p> |
| 84 | </form> |
| 85 | <?php |
| 86 | $mathpage = ob_get_contents(); |
| 87 | ob_end_clean(); |
| 88 | wp_die( |
| 89 | $mathpage, |
| 90 | '', |
| 91 | array ( 'response' => 401 ) |
| 92 | ); |
| 93 | } |
| 94 | |
| 95 | public function process_generate_math_page() { |
| 96 | $salt = get_site_option( 'jetpack_protect_key' ) . get_site_option( 'admin_email' ); |
| 97 | $ans = (int)$_POST['jetpack_protect_num']; |
| 98 | $salted_ans = sha1( $salt . $ans ); |
| 99 | $correct_ans = $_POST[ 'jetpack_protect_answer' ]; |
| 100 | |
| 101 | if ( $salted_ans != $correct_ans ) { |
| 102 | Jetpack_Protect_Math_Authenticate::generate_math_page(true); |
| 103 | } else { |
| 104 | $temp_pass = substr( sha1( rand( 1, 100000000 ) . get_site_option( 'jetpack_protect_key' ) ), 5, 25 ); |
| 105 | |
| 106 | $jetpack_protect = Jetpack_Protect_Module::instance(); |
| 107 | $jetpack_protect->set_transient( 'jpp_math_pass_' . $temp_pass, 3, DAY_IN_SECONDS ); |
| 108 | setcookie('jpp_math_pass', $temp_pass, time() + DAY_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN, false); |
| 109 | return true; |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | /** |
| 114 | * Requires a user to solve a simple equation. Added to any WordPress login form. |
| 115 | * |
| 116 | * @return VOID outputs html |
| 117 | */ |
| 118 | static function math_form() { |
| 119 | $salt = get_site_option( 'jetpack_protect_key' ) . get_site_option( 'admin_email' ); |
| 120 | $num1 = rand( 0, 10 ); |
| 121 | $num2 = rand( 1, 10 ); |
| 122 | $sum = $num1 + $num2; |
| 123 | $ans = sha1( $salt . $sum ); |
| 124 | ?> |
| 125 | <div style="margin: 5px 0 20px;"> |
| 126 | <label for="jetpack_protect_answer"> |
| 127 | <?php esc_html_e( 'Prove your humanity', 'jetpack' ); ?> |
| 128 | </label> |
| 129 | <br/> |
| 130 | <span style="vertical-align:super;"> |
| 131 | <?php echo "$num1 + $num2 = "; ?> |
| 132 | </span> |
| 133 | <input |
| 134 | type="text" |
| 135 | id="jetpack_protect_answer" |
| 136 | name="jetpack_protect_num" |
| 137 | value="" |
| 138 | size="2" |
| 139 | style="width:30px;height:25px;vertical-align:middle;font-size:13px;" |
| 140 | class="input" /> |
| 141 | <input type="hidden" name="jetpack_protect_answer" value="<?php echo $ans; ?>" /> |
| 142 | </div> |
| 143 | <?php |
| 144 | } |
| 145 | |
| 146 | } |
| 147 | } |
| 148 |