includes/functions-auth.php

   1 <?php\r
   2 // Check for valid user. Returns true or an error message\r
   3 function yourls_is_valid_user() {\r
   4         static $valid = false;\r
   5         \r
   6         if( $valid )\r
   7                 return true;\r
   8 \r
   9         // Logout request\r
  10         if( isset( $_GET['mode'] ) && $_GET['mode'] == 'logout') {\r
  11                 yourls_store_cookie( null );\r
  12                 return 'Logged out successfully';\r
  13         }\r
  14         \r
  15         // Check cookies or login request. Login form has precedence.\r
  16         global $yourls_user_passwords;\r
  17         \r
  18         // In the future maybe I'll implement nonces like in WP. Will be something like\r
  19         // ?nonce=fn(login,pwd,action)\r
  20         \r
  21         // Determine auth method and check credentials\r
  22         if\r
  23                 // API only: Secure (no login or pwd) and time limited token\r
  24                 // ?timestamp=12345678&signature=md5(totoblah12345678)\r
  25                 ( yourls_is_API() &&\r
  26                   isset($_REQUEST['timestamp']) && !empty($_REQUEST['timestamp']) &&\r
  27                   isset($_REQUEST['signature'])\r
  28                 )\r
  29                 {\r
  30                         $valid = yourls_check_signature_timestamp();\r
  31                 }\r
  32                 \r
  33         elseif\r
  34                 // API only: Secure (no login or pwd)\r
  35                 // ?signature=md5(totoblah)\r
  36                 ( yourls_is_API() &&\r
  37                   !isset($_REQUEST['timestamp']) &&\r
  38                   isset($_REQUEST['signature'])\r
  39                 )\r
  40                 {\r
  41                         $valid = yourls_check_signature();\r
  42                 }\r
  43         \r
  44         elseif\r
  45                 // API or normal: login with username & pwd\r
  46                 ( isset($_REQUEST['username']) && isset($_REQUEST['password']) )\r
  47                 {\r
  48                         $valid = yourls_check_username_password();\r
  49                 }\r
  50         \r
  51         elseif\r
  52                 // Normal only: cookies\r
  53                 ( isset($_COOKIE['yourls_username']) && isset($_COOKIE['yourls_password']) )\r
  54                 {\r
  55                         $valid = yourls_check_auth_cookie();\r
  56                 }\r
  57 \r
  58         // Login for the win!\r
  59         if ( $valid ) {\r
  60                 // (Re)store encrypted cookie and tell it's ok\r
  61                 if ( !yourls_is_API() ) // No need to store a cookie when used in API mode.\r
  62                         yourls_store_cookie( YOURLS_USER );\r
  63                 return true;\r
  64         }\r
  65         \r
  66         // Login failed\r
  67         if ( isset($_REQUEST['username']) || isset($_REQUEST['password']) ) {\r
  68                 return 'Invalid username or password';\r
  69         } else {\r
  70                 return 'Please log in';\r
  71         }\r
  72 }\r
  73 \r
  74 // Check auth against list of login=>pwd. Sets user if applicable, returns bool\r
  75 function yourls_check_username_password() {\r
  76         global $yourls_user_passwords;\r
  77         if( $yourls_user_passwords[ $_REQUEST['username'] ] == $_REQUEST['password'] ) {\r
  78                 yourls_set_user( $_REQUEST['username'] );\r
  79                 return true;\r
  80         }\r
  81         return false;\r
  82 }\r
  83 \r
  84 // Check auth against encrypted COOKIE data. Sets user if applicable, returns bool\r
  85 function yourls_check_auth_cookie() {\r
  86         global $yourls_user_passwords;\r
  87         foreach( $yourls_user_passwords as $valid_user => $valid_password ) {\r
  88                 if( \r
  89                         yourls_salt($valid_user) == $_COOKIE['yourls_username']\r
  90                         && yourls_salt($valid_password) == $_COOKIE['yourls_password'] \r
  91                 ) {\r
  92                         yourls_set_user( $valid_user );\r
  93                         return true;\r
  94                 }\r
  95         }\r
  96         return false;\r
  97 }\r
  98 \r
  99 // Check auth against signature and timestamp. Sets user if applicable, returns bool\r
 100 function yourls_check_signature_timestamp() {\r
 101         // Timestamp in PHP : time()\r
 102         // Timestamp in JS: parseInt(new Date().getTime() / 1000)\r
 103         global $yourls_user_passwords;\r
 104         foreach( $yourls_user_passwords as $valid_user => $valid_password ) {\r
 105                 if (\r
 106                         (\r
 107                                 md5( $_REQUEST['timestamp'].yourls_auth_signature( $valid_user ) ) == $_REQUEST['signature']\r
 108                                 or\r
 109                                 md5( yourls_auth_signature( $valid_user ).$_REQUEST['timestamp'] ) == $_REQUEST['signature']\r
 110                         )\r
 111                         &&\r
 112                         yourls_check_timestamp( $_REQUEST['timestamp'] )\r
 113                         ) {\r
 114                         yourls_set_user( $valid_user );\r
 115                         return true;\r
 116                 }\r
 117         }\r
 118         return false;\r
 119 }\r
 120 \r
 121 // Check auth against signature. Sets user if applicable, returns bool\r
 122 function yourls_check_signature() {\r
 123         global $yourls_user_passwords;\r
 124         foreach( $yourls_user_passwords as $valid_user => $valid_password ) {\r
 125                 if ( yourls_auth_signature( $valid_user ) == $_REQUEST['signature'] ) {\r
 126                         yourls_set_user( $valid_user );\r
 127                         return true;\r
 128                 }\r
 129         }\r
 130         return false;\r
 131 }\r
 132 \r
 133 // Generate secret signature hash\r
 134 function yourls_auth_signature( $username = false ) {\r
 135         if( !$username && defined('YOURLS_USER') ) {\r
 136                 $username = YOURLS_USER;\r
 137         }\r
 138         return ( $username ? substr( yourls_salt( $username ), 0, 10 ) : 'Cannot generate auth signature: no username' );\r
 139 }\r
 140 \r
 141 // Check a timestamp is from the past and not too old\r
 142 function yourls_check_timestamp( $time ) {\r
 143         $now = time();\r
 144         return ( $now >= $time && ceil( $now - $time ) < YOURLS_NONCE_LIFE );\r
 145 }\r
 146 \r
 147 // Store new cookie. No $user will delete the cookie.\r
 148 function yourls_store_cookie( $user = null ) {\r
 149         if( !$user ) {\r
 150                 $pass = null;\r
 151                 $time = time() - 3600;\r
 152         } else {\r
 153                 global $yourls_user_passwords;\r
 154                 if( isset($yourls_user_passwords[$user]) ) {\r
 155                         $pass = $yourls_user_passwords[$user];\r
 156                 } else {\r
 157                         die('Stealing cookies?'); // This should never happen\r
 158                 }\r
 159                 $time = time() + YOURLS_COOKIE_LIFE;\r
 160         }  \r
 161         setcookie('yourls_username', yourls_salt( $user ), $time, '/' );\r
 162         setcookie('yourls_password', yourls_salt( $pass ), $time, '/' );\r
 163 }\r
 164 \r
 165 // Set user name\r
 166 function yourls_set_user( $user ) {\r
 167         if( !defined('YOURLS_USER') )\r
 168                 define('YOURLS_USER', $user);\r
 169 }\r