Pfthb

I've been trying to implement USSD using SMPP protocol before I shared my problem, I will talk about what've been able to achieve so far:

1. I have been able to successfully connect with the Telco via VPN


2. I have been able to initiate SMPP Connection and returned an appropriate response of Response_Code '0' which is 'OK'


3. Binding of Receiver, Transceiver & Transmitter with command_id '0x00000001', '0x00000009', '0x00000002' respectively, and they all return expected Response_Code which is 'OK'.

But the following are my problems:

1. I want to be able to bind, and when the user dials the USSD ShortCode, they should be able to see at least 'Hello World'


2. Unable to implement 'submit_sm' after successful 'transceiver' bind


3. My current code implementation is using SMPP to send SMS, of which is running fine, but will like to have another method e.g. $tx->runUSSD() instead of $tx->sendSMS()

Below are my codes, and I believe with this code I should be able to do it, but have been so freaking stress with research and research, I've read and have read a lot, but can't get it working:

transciever.php

<?php
 print "<pre>";
 require_once "./smpp.php";
 $tx=new SMPP('Ip Address',Port);
 $tx->debug=true;
 $tx->addr_npi=1;
 print "open status: ".$tx->state."n";
 $tx->bindTransceiver("system_id","password");
 $tx->sms_source_addr_npi=0;
 $tx->sms_source_addr_ton=5;
 $tx->sms_dest_addr_ton=1;
 $tx->sms_dest_addr_npi=1;

 $status = $tx->sendSMS("Hello","08023828392","Hello World");
 $tx->close();
 unset($tx);
 echo $status;
 print "</pre>";
?>

smpp.php

<?php

class SMPP
 var $debug = true;
 //SMPP bind parameters
 //var $system_type="WWW";
 var $interface_version=0x34;
 var $addr_ton=0;
 var $addr_npi=0;
 var $address_range="";
 //ESME transmitter parameters
 var $sms_service_type="";
 var $sms_source_addr_ton=0;
 var $sms_source_addr_npi=0;
 var $sms_dest_addr_ton=0;
 var $sms_dest_addr_npi=0;
 var $sms_esm_class=0;
 var $sms_protocol_id=0;
 var $sms_priority_flag=0;
 var $sms_schedule_delivery_time="";
 var $sms_validity_period="";
 var $sms_registered_delivery_flag=0;
 var $sms_replace_if_present_flag=0;
 var $sms_data_coding=0;
 var $sms_sm_default_msg_id=0;

 /**
 * Constructs the smpp class
 * @param $host - SMSC host name or host IP
 * @param $port - SMSC port
 */
 function SMPP($host, $port=5016)
 //internal parameters
 $this->sequence_number=1;
 $this->debug=false;
 $this->pdu_queue=array();
 $this->host=$host;
 $this->port=$port;
 $this->state="closed";
 //open the socket
 $this->socket=fsockopen($this->host, $this->port, $errno, $errstr, 30);
 if($this->socket)$this->state="open";
 

 /**
 * Binds the receiver. One object can be bound only as receiver or only as trancmitter.
 * @param $login - ESME system_id
 * @param $port - ESME password
 * @return true when bind was successful
 */
 function bindTransceiver($login, $pass)
 if($this->state!="open")return false;
 if($this->debug)
 echo "Binding transciever...nn";
 
 $status=$this->_bind($login, $pass, 0x00000009);
 if($this->debug)
 echo "Binding status : $statusnn";
 
 if($status===0)$this->state="bind_trx";
 return ($status===0);
 

 /**
 * Binds the receiver. One object can be bound only as receiver or only as trancmitter.
 * @param $login - ESME system_id
 * @param $port - ESME password
 * @return true when bind was successful
 */
 function bindReceiver($login, $pass)
 if($this->state!="open")return false;
 if($this->debug)
 echo "Binding receiver...nn";
 
 $status=$this->_bind($login, $pass, 0x00000001);
 if($this->debug)
 echo "Binding status : $statusnn";
 
 if($status===0)$this->state="bind_rx";
 return ($status===0);
 
 /**
 * Binds the transmitter. One object can be bound only as receiver or only as trancmitter.
 * @param $login - ESME system_id
 * @param $port - ESME password
 * @return true when bind was successful
 */
 function bindTransmitter($login, $pass)
 if($this->state!="open")return false;
 if($this->debug)
 echo "Binding transmitter...nn";
 
 $status=$this->_bind($login, $pass, 0x00000002);
 if($this->debug)
 echo "Binding status : $statusnn";
 
 if($status===0)$this->state="bind_tx";
 return ($status===0);
 
 /**
 * Closes the session on the SMSC server.
 */
 function close()
 if($this->state=="closed")return;
 if($this->debug)
 echo "Unbinding...nn";
 
 $status=$this->sendCommand(0x00000006,"");
 if($this->debug)
 echo "Unbind status : $statusnn";
 
 fclose($this->socket);
 $this->state="closed";
 

 /**
 * Read USSD response from SMSC.
 * @return 
 */
 function readResponse () 
 if($this->state!="bind_trx")return false;

 //set command id
 $command_id = 0x00000005;
 
 /**
 * Read one SMS from SMSC. Can be executed only after bindReceiver() call. 
 * This method bloks. Method returns on socket timeout or enquire_link signal from SMSC.
 * @return sms associative array or false when reading failed or no more sms.
 */
 function readSMS()
 if($this->state!="bind_rx")return false;
 //stream_set_timeout($this->socket, 10);
 $command_id=0x00000005;
 //check the queue
 for($i=0;$i<count($this->pdu_queue);$i++)
 $pdu=$this->pdu_queue[$i];
 if($pdu['id']==$command_id)
 //remove responce
 array_splice($this->pdu_queue, $i, 1);
 return parseSMS($pdu);
 
 
 //read pdu
 do
 if($this->debug)
 echo "read sms...nn";
 
 $pdu=$this->readPDU();
 //check for enquire link command
 if($pdu['id']==0x00000015)
 $this->sendPDU(0x80000015, "", $pdu['sn']);
 return false;
 
 array_push($this->pdu_queue, $pdu);
 while($pdu && $pdu['id']!=$command_id);
 if($pdu)
 array_pop($this->pdu_queue);
 return $this->parseSMS($pdu);
 
 return false;
 
 /**
 * Read one SMS from SMSC. Can be executed only after bindTransmitter() call.
 * @return true on succesfull send, false if error encountered
 */
 function sendSMS($from, $to, $message)

 ////////////////private functions///////////////

 /**
 * @private function
 * Binds the socket and opens the session on SMSC
 * @param $login - ESME system_id
 * @param $port - ESME password
 * @return bind status or false on error
 */
 function _bind($login, $pass, $command_id)
 //make PDU
 $pdu = pack(
 'a'.(strlen($login)+1).
 'a'.(strlen($pass)+1).
 'a'.(strlen($this->system_type)+1).
 'CCCa'.(strlen($this->address_range)+1),
 $login, $pass, $this->system_type,
 $this->interface_version, $this->addr_ton,
 $this->addr_npi, $this->address_range);
 $status=$this->sendCommand($command_id,$pdu);
 return $status;
 

 /**
 * @private function
 * Parse deliver PDU from SMSC.
 * @param $pdu - deliver PDU from SMSC.
 * @return parsed PDU as array.
 */
 function parseSMS($pdu)
 //check command id
 if($pdu['id']!=0x00000005)return false;
 //unpack PDU
 $ar=unpack("C*",$pdu['body']);
 $sms=array('service_type'=>$this->getString($ar,6),
 'source_addr_ton'=>array_shift($ar),
 'source_addr_npi'=>array_shift($ar),
 'source_addr'=>$this->getString($ar,21),
 'dest_addr_ton'=>array_shift($ar),
 'dest_addr_npi'=>array_shift($ar),
 'destination_addr'=>$this->getString($ar,21),
 'esm_class'=>array_shift($ar),
 'protocol_id'=>array_shift($ar),
 'priority_flag'=>array_shift($ar),
 'schedule_delivery_time'=>array_shift($ar),
 'validity_period'=>array_shift($ar),
 'registered_delivery'=>array_shift($ar),
 'replace_if_present_flag'=>array_shift($ar),
 'data_coding'=>array_shift($ar),
 'sm_default_msg_id'=>array_shift($ar),
 'sm_length'=>array_shift($ar),
 'short_message'=>$this->getString($ar,255)
 );
 if($this->debug)
 echo "Delivered sms:n";
 print_r($sms);
 echo "n";
 
 //send responce of recieving sms
 $this->sendPDU(0x80000005, "", $pdu['sn']);
 return $sms;
 
 /**
 * @private function
 * Sends the PDU command to the SMSC and waits for responce.
 * @param $command_id - command ID
 * @param $pdu - PDU body
 * @return PDU status or false on error
 */
 function sendCommand($command_id, $pdu)
 if($this->state=="closed")return false;
 $this->sendPDU($command_id, $pdu, $this->sequence_number);
 $status=$this->readPDU_resp($this->sequence_number, $command_id);
 $this->sequence_number=$this->sequence_number+1;
 return $status;
 
 /**
 * @private function
 * Prepares and sends PDU to SMSC.
 * @param $command_id - command ID
 * @param $pdu - PDU body
 * @param $seq_number - PDU sequence number
 */
 function sendPDU($command_id, $pdu, $seq_number)
 $length=strlen($pdu) + 16;
 $header=pack("NNNN", $length, $command_id, 0, $seq_number);
 if($this->debug)
 echo "Send PDU : $length bytesn";
 $this->printHex($header.$pdu);
 echo "command_id : ".$command_id."n";
 echo "sequence number : $seq_numbernn";
 
 fwrite($this->socket, $header.$pdu, $length);
 
 /**
 * @private function
 * Waits for SMSC responce on specific PDU.
 * @param $seq_number - PDU sequence number
 * @param $command_id - PDU command ID
 * @return PDU status or false on error
 */
 function readPDU_resp($seq_number, $command_id)0x80000000;
 //check queue
 for($i=0;$i<count($this->pdu_queue);$i++)
 $pdu=$this->pdu_queue[$i];
 if($pdu['sn']==$seq_number && $pdu['id']==$command_id)
 //remove responce
 array_splice($this->pdu_queue, $i, 1);
 return $pdu['status'];
 
 
 //read pdu
 do
 $pdu=$this->readPDU();
 if($pdu)array_push($this->pdu_queue, $pdu);
 while($pdu && ($pdu['sn']!=$seq_number 
 /**
 * @private function
 * Reads incoming PDU from SMSC.
 * @return readed PDU or false on error.
 */
 function readPDU()
 //read PDU length
 $tmp=fread($this->socket, 4);
 if(!$tmp)return false;
 extract(unpack("Nlength", $tmp));
 //read PDU headers
 $tmp2=fread($this->socket, 12);
 if(!$tmp2)return false;
 extract(unpack("Ncommand_id/Ncommand_status/Nsequence_number", $tmp2));
 //read PDU body
 if($length-16>0)
 $body=fread($this->socket, $length-16);
 if(!$body)return false;
 else
 $body="";
 
 if($this->debug)
 echo "Read PDU : $length bytesn";
 $this->printHex($tmp.$tmp2.$body);
 echo "body len : " . strlen($body) . "n";
 echo "Command id : $command_idn";
 echo "Command status : $command_statusn";
 echo "sequence number : $sequence_numbernn";
 
 $pdu=array(
 'id'=>$command_id,
 'status'=>$command_status,
 'sn'=>$sequence_number,
 'body'=>$body);
 return $pdu;
 
 /**
 * @private function
 * Reads C style zero padded string from the char array.
 * @param $ar - input array
 * @param $maxlen - maximum length to read.
 * @return readed string.
 */
 function getString(&$ar, $maxlen=255)
 $s="";
 $i=0;
 do
 $c=array_shift($ar);
 if($c!=0)$s.=chr($c);
 $i++;
 while($i<$maxlen && $c!=0);
 return $s;
 
 /**
 * @private function
 * Prints the binary string as hex bytes.
 * @param $maxlen - maximum length to read.
 */
 function printHex($pdu)
 $ar=unpack("C*",$pdu);
 foreach($ar as $v)
 $s=dechex($v);
 if(strlen($s)<2)$s="0$s";
 print "$s ";
 
 print "n";
 

?>

I hope to hear from you guys.
Thank you in advance.