moving to an overload function
[ga4php.git] / lib / lib.php
index 883ccb9..42bc599 100644 (file)
 <?php
 
+
+/*
+ * TODO's:
+ * Implement TOTP fully
+ * Error checking, lots of error checking
+ * have a way of encapsulating token data stright into a single field so it could be added
+ *    in some way to a preexisting app without modifying the DB as such... or by just adding
+ *    a single field to a user table...
+ * Remove all reliance on the SQLite database. Data should come from the encasultating application
+ *    which will be expected to provde two function calls where it can get/store data - DONE
+ */
+
+/*
+ * I am an idiot.
+ * For some reason i had it in my head to pass static functions into the construct
+ * of the class in order to hand data going in/out
+ * when in reality i should be making the data in/out func's abstract
+ * and getting implementors to extend the class
+ * 
+ * For now im going to keep implementing it this way and thus my class will
+ * forever be an example of poor design choices. It'll change it very shortly though 
+ */
+
+/*
+ * The way we should really be doing things is to have an array that encapsulates "normal" data (or a class?)
+ * and then just manipulate it, then use a checkin function to push the data base into the db...
+ */
 class GoogleAuthenticator {
        
        // first we init google authenticator by passing it a filename
        // for its sqlite database.
-       function __construct($file) {
-               if(file_exists($file)) {
-                       try {
-                               $this->dbConnector = new PDO("sqlite:$file");
-                       } catch(PDOException $exep) {
-                               $this->errorText = $exep->getMessage();
-                               $this->dbConnector = false;
-                       }                       
-               } else {
-                       setupDB();
-               }
+       // $getDataFunction expects 1 argument which defines what data it wants
+       // and can be "userlist" or "usertoken:username"
+       // $putDataFunciton expects 2 arguments, $1 is data type, $2 is the data
+       // $1 can be "changetoken:username", "removetoken:username", $2 is the token
+       // data in some encoded form
+       // tokenDATA will be like HOTP;KEY;CID where CID is the current counter value
+       // why encode like this? i cant think of a good reason tbh, i should probably just
+       // use php's arry encoder functions  
+       function __construct($getDataFunction, $putDataFunction) {
+               $this->putDataFunction = $putDataFunction;
+               $this->getDataFunction = $getDataFunction;
+       }
+       
+       abstract function getData($username);
+       abstract function putData($username, $data);
+       abstract function getUsers();
+       
+       // a function to create an empty data structure
+       function createEmptyData() {
+               $data["tokenkey"] = ""; // the token key
+               $data["tokentype"] = ""; // the token type
+               $data["tokentimer"] = ""; // the token timer (For totp) and not supported by ga yet             
+               $data["tokencounter"] = ""; // the token counter for hotp
+               $data["tokenalgorithm"] = ""; // the token algorithm (not supported by ga yet)
                
-               $this->dbFile = $file;
+               return $data;
        }
        
-       // creates the database (tables);
-       function setupDB() {
-               try {
-                       $this->$dbConnector = new PDO("sqlite:$file");
-               } catch(PDOException $exep) {
-                       $this->errorText = $exep->getMessage();
-                       $this->dbConnector = false;
-               }                       
+       // an internal funciton to get 
+       function internalGetData($username) {
+               $data = getData($username);
+               $deco = unserialize(base64_decode($data));
+               
+               if(!$deco) {
+                       $deco = createEmptyData();
+               }
+               
+               return $deco;
+       }
        
-               // here we create some tables and stuff
+
+       function internalPutData($username, $data) {
+               $enco = base64_encode(serialize($data));
+               
+               return putData($username, $enco);
        }
        
-       // creates "user" in the database and returns a url for
-       // the phone. If user already exists, this returns false
-       // if any error occurs, this returns false
-       function setupUser($username) {
-               $key = _createBase32Key();
+
+       // set the token type the user it going to use.
+       // this defaults to HOTP - we only do 30s token
+       // so lets not be able to set that yet
+       function setupTokenType($username, $tokentype) {
+               if($tokentype!="HOTP" and $tokentype!="TOTP") {
+                       $errorText = "Invalid Token Type";
+                       return false;
+               }
+               
+               $data = getData($username);
+               $data["tokentype"] = $tokentype;
+               $func = $this->putDataFunction;
+               $func("settokentype", $put);
+               
+               return true;    
        }
        
-       // Replcate "user" in the database... All this really
-       // does is to replace the key for the user. Returns false
-       // if the user doesnt exist of the key is poop
-       function replaceUser($username) {
+       
+       // create "user" with insert
+       function setUser($username, $key = "", $ttype="HOTP") {
+               if($key == "") $key = $this->createBase32Key();
+               $hkey = $this->helperb322hex($key);
                
+               $token["username"] = $username;
+               $token["tokenkey"] = $hkey;
+               $token["tokentype"] = $ttype;
+               
+               $func = $this->putDataFunction;
+               $func("setusertoken", $token);
+               
+               return $key;
        }
        
+       
        // sets the key for a user - this is assuming you dont want
        // to use one created by the application. returns false
        // if the key is invalid or the user doesn't exist.
        function setUserKey($username, $key) {
-               
+               // consider scrapping this
+       }
+       
+       
+       // have user?
+       function userExists($username) {
+               // need to think about this
        }
        
+       
        // self explanitory?
        function deleteUser($username) {
-               
+               $func = $this->putDataFunction;
+               $func("deleteusertoken", $username);
        }
        
        // user has input their user name and some code, authenticate
        // it
        function authenticateUser($username, $code) {
                
+               $func = $this->getDataFunction;
+               $tokendata = $func("gettoken", $username);
+               
+               // TODO: check return value
+               $ttype = $tokendata["tokentype"];
+               $tlid = $tokendata["tokencounter"];
+               $tkey = $tokendata["tokenkey"];
+               switch($ttype) {
+                       case "HOTP":
+                               $st = $tlid;
+                               $en = $tlid+20;
+                               for($i=$st; $i<$en; $i++) {
+                                       $stest = $this->oath_hotp($tkey, $i);
+                                       //error_log("code: $code, $stest, $tkey, $tid");
+                                       if($code == $stest) {
+                                               $tokenset["username"] = $username;
+                                               $tokenset["tokencounter"] = $i;
+                                               
+                                               $func = $this->putDataFunction;
+                                               $func("settokencounter", $tokenset);
+                                               return true;
+                                       }
+                               }
+                               return false;
+                               break;
+                       case "TOTP":
+                               $t_now = time();
+                               $t_ear = $t_now - 45;
+                               $t_lat = $t_now + 60;
+                               $t_st = ((int)($t_ear/30));
+                               $t_en = ((int)($t_lat/30));
+                               //error_log("kmac: $t_now, $t_ear, $t_lat, $t_st, $t_en");
+                               for($i=$t_st; $i<=$t_en; $i++) {
+                                       $stest = $this->oath_hotp($tkey, $i);
+                                       //error_log("code: $code, $stest, $tkey\n");
+                                       if($code == $stest) {
+                                               return true;
+                                       }
+                               }
+                               break;
+                       default:
+                               echo "how the frig did i end up here?";
+               }
+               
+               return false;
+
        }
        
        // this function allows a user to resync their key. If too
        // many codes are called, we only check up to 20 codes in the future
        // so if the user is at 21, they'll always fail. 
        function resyncCode($username, $code1, $code2) {
-                       
+               // here we'll go from 0 all the way thru to 200k.. if we cant find the code, so be it, they'll need a new one
+               // for HOTP tokens we start at x and go to x+20
+               
+               // for TOTP we go +/-1min TODO = remember that +/- 1min should
+               // be changed based on stepping if we change the expiration time
+               // for keys
+               
+               //              $this->dbConnector->query('CREATE TABLE "tokens" ("token_id" INTEGER PRIMARY KEY AUTOINCREMENT,"token_key" TEXT NOT NULL, "token_type" TEXT NOT NULL, "token_lastid" INTEGER NOT NULL)');
+               
+               $func = $this->getDataFunction;
+               $tokendata = $func("gettoken", $username);
+               
+               // TODO: check return value
+               $ttype = $tokendata["tokentype"];
+               $tlid = $tokendata["tokencounter"];
+               $tkey = $tokendata["tokenkey"];
+               
+               switch($ttype) {
+                       case "HOTP":
+                               $st = 0;
+                               $en = 200000;
+                               for($i=$st; $i<$en; $i++) {
+                                       $stest = $this->oath_hotp($tkey, $i);
+                                       //echo "code: $code, $stest, $tkey\n";
+                                       if($code1 == $stest) {
+                                               $stest2 = $this->oath_hotp($tkey, $i+1);
+                                               if($code2 == $stest2) {
+                                                       $tokenset["username"] = $username;
+                                                       $tokenset["tokencounter"] = $i+1;
+                                               
+                                                       $func = $this->putDataFunction;
+                                                       $func("settokencounter", $tokenset);
+                                                       return true;
+                                               }
+                                       }
+                               }
+                               return false;
+                               break;
+                       case "TOTP":
+                               break;
+                       default:
+                               echo "how the frig did i end up here?";
+               }
+               
+               return false;
+               
        }
        
        // gets the error text associated with the last error
@@ -76,8 +243,15 @@ class GoogleAuthenticator {
        }
        
        // create a url compatibile with google authenticator.
-       function createURL($user, $key) {
-               $url = "otpauth://hotp/$user?secret=$key";
+       function createURL($user, $key,$toktype = "HOTP") {
+               // oddity in the google authenticator... hotp needs to be lowercase.
+               $toktype = strtolower($toktype);
+               if($toktype == "hotp") {
+                       $url = "otpauth://$toktype/$user?secret=$key&counter=1";
+               } else {
+                       $url = "otpauth://$toktype/$user?secret=$key";
+               }
+               //echo "url: $url\n";
                return $url;
        }
        
@@ -102,10 +276,10 @@ class GoogleAuthenticator {
         $dous = "";
 
         for($i = 0; $i < strlen($b32); $i++) {
-                $in = strrpos($alphabet, $b32[$i]);
-                $b = str_pad(base_convert($in, 10, 2), 5, "0", STR_PAD_LEFT);
-                $out .= $b;
-                $dous .= $b.".";
+               $in = strrpos($alphabet, $b32[$i]);
+               $b = str_pad(base_convert($in, 10, 2), 5, "0", STR_PAD_LEFT);
+            $out .= $b;
+            $dous .= $b.".";
         }
 
         $ar = str_split($out,20);
@@ -148,10 +322,52 @@ class GoogleAuthenticator {
         return $out2;
        }
        
+       function oath_hotp($key, $counter)
+       {
+               $key = pack("H*", $key);
+           $cur_counter = array(0,0,0,0,0,0,0,0);
+           for($i=7;$i>=0;$i--)
+           {
+               $cur_counter[$i] = pack ('C*', $counter);
+               $counter = $counter >> 8;
+           }
+           $bin_counter = implode($cur_counter);
+           // Pad to 8 chars
+           if (strlen ($bin_counter) < 8)
+           {
+               $bin_counter = str_repeat (chr(0), 8 - strlen ($bin_counter)) . $bin_counter;
+           }
+       
+           // HMAC
+           $hash = hash_hmac ('sha1', $bin_counter, $key);
+           return str_pad($this->oath_truncate($hash), 6, "0", STR_PAD_LEFT);
+       }
+       
+       function oath_truncate($hash, $length = 6)
+       {
+           // Convert to dec
+           foreach(str_split($hash,2) as $hex)
+           {
+               $hmac_result[]=hexdec($hex);
+           }
+       
+           // Find offset
+           $offset = $hmac_result[19] & 0xf;
+       
+           // Algorithm from RFC
+           return
+           (
+               (($hmac_result[$offset+0] & 0x7f) << 24 ) |
+               (($hmac_result[$offset+1] & 0xff) << 16 ) |
+               (($hmac_result[$offset+2] & 0xff) << 8 ) |
+               ($hmac_result[$offset+3] & 0xff)
+           ) % pow(10,$length);
+       }
+       
        
        // some private data bits.
+       private $getDatafunction;
+       private $putDatafunction;
        private $errorText;
-       private $dbFile;
-       private $dbConnector;
 }
 ?>
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