如何建立连接的短信pdu?得到垃圾字符

时间:2012-09-06 10:56:56

标签: php sms telnet pdu

我正在尝试构建一些PHP代码,通过telnet将短信发送到SIM服务器,但我在发送连锁消息方面遇到了麻烦。

我已经阅读了一些关于使用填充位来使编码消息septets成为八位字节的内容,但我并不完全理解它是如何工作的。

我有一个班级接收电话号码,邮件(已经分为153个最大值),短信总数和当前部分文本的订单号。

只要我在$ hexmessage之前添加'20',它就可以正常工作。但是我在第一部分的开头(在我的msg的第一个字母之前)得到一个垃圾字符,并且相同的垃圾字符替换了第二部分的第一个字母! (使用'20'因此它会显示一个空格,但它显示一个三角形)

我无法理解为什么,或者我必须改变它才能正常工作。

我希望有人可以帮助我理解我做错了什么。

这是我到目前为止所得到的:

<?php

 // Generate PDU string
public function generatePDUm($receiverNumber,$message, $sms_count, $msg_nr) {

    //Append filler digit if number is national
    if( strlen($receiverNumber)==9){
        $nacional=1;
        $receiverNumber = $receiverNumber."F";                              
        $network = substr($receiverNumber, 0, 2);                       //NETWORK code, used to decide the SIM Card to be used

    //Check for international flags and set the number type accordingly
    }else{
        $nacional=0;
        if(substr($receiverNumber, 0, 1)=='+'){
            $network = substr($receiverNumber, 4, 2);                   //NETWORK code, used to decide the SIM Card to be used 
            $receiverNumber = substr($receiverNumber, 1, 12);           //remove international indicator    
        } 
        else if(substr($receiverNumber, 0, 2)== '00'){
            $network = substr($receiverNumber, 5, 2);                   //NETWORK code, used to decide the SIM Card to be used 
            $receiverNumber = substr($receiverNumber, 2, 12);           //remove international indicator
        }

    }

    /* Flag the network to be used */
    switch ($network){
        case  "92":
            $network="TMN";
            break;

        case  "96":
            $network="TMN";
            break;

        case "91":
            $network="VODAFONE";
            break;

        case "93":
            $network="OPTIMUS";
            break;
    }
    // Receiver number must be 10 characters long ('national nr' + filler digit) or less than 13 ('351'+'national nr'). (Portugal)
    if( strlen($receiverNumber) < 10 || strlen($receiverNumber) > 12) {
        // Error, not 10 or over 12 numbers long (Code 1)
        $this->setErrorCode(1);
        return false;
    }

    // Message must be 2 characters long at least
    if( strlen($message) < 2 ) {
        // Error, message too short (Code 2)
        $this->setErrorCode(2);
        return false;
    }

    // Message can't be longer than 153 characters. 3SMS.
    if( strlen($message) > 153 ) {
        // Error, message too long (Code 3)
        $this->setErrorCode(3);
        return false;
    }

    // Length of servicecenter number (00 = automatically fixed by phone)
    $serviceCenterNumberLength = '00';

    // SMS-? : 04=sms-deliver(recieve), 11=sms-submit, 01 = dont know but it works, 41 = SMS-SUBMIT + UDH bit (for extended/concatenated SMS)
    // You can try to change this if your phone does not work with 01 command try to use 11 command
    $smsType = '41';

    // TP Message Reference: (placeholder), let the phone set the message reference number itself
    $messageRef = '00';

    // Number length. If national -> 9, if international -> 12
    if($nacional==1){
        $numberLength = '09';
    }else{
        $numberLength = '0C';
    }


    // Type of phone adress: (81=Unknown=10dec, 91=InternationalFormat, 92=National?)
    if($nacional==1){
        $numberType = '81';
    }else{
        $numberType = '91';
    }

    // Get the PDU version of the number
    $number = $this->getNumberAsPDU( $receiverNumber );

    // TP-PID (Protocol Identifier)
    $protocolId = '00';

    // TP-DCS (Data coding scheme)
    $dataCodingScheme = '00';

    // TP-Validity-Period (timestamp), AA=4days expiry, disabled for SonyEricsson support.
   // $validityPeriod = 'A0';
    // $validityPeriod = 'AA'; // Add this if the PDU command fails

    /*user data header information (05 - User Data header info length 
    *                               00 - Information element identifier for a concatenated short message
    *                               03 - Information element data length
    *                               00 - Reference number, auto
    *                               0.$sms_count - total SMS nr
    *                               0.$msg_nr    - current SMS order */
    $udhi = '050003000'.$sms_count.'0'.$msg_nr;
   // echo 'UDHinfo: '.$udhi."\n";

    // Data length of message (in hex format)
    $dataLength = $this->strToHexLen($message);
   // echo 'DATA LENGHT: '.$dataLength."\n\n";

    // Convert message, string > 7bits > 8bits > hex
    $hexMessage = $this->bit7tohex( $this->strto7bit( $message ) );


    // Create the complete PDU string
    $pdu = $serviceCenterNumberLength . $smsType . $messageRef . $numberLength .
            $numberType . $number . $protocolId . $dataCodingScheme . $dataLength .
            $udhi . '20' .$hexMessage;

    /*
     * Generate the length of var $pdu (pdu/2 minus 1) as pdu format requests
     * The -1 is because we don't count the first two characters '00', needed for this command: 'cmgs=24'
     */
    $cmgslen = strlen($pdu)/2-1;

    // Build data array to return with required information
    $data = array();
    $data['pdu'] = $pdu;
    $data['cmgslen'] = $cmgslen;
    $data['rede'] = $network;

    // Return the data array with PDU information
    return $data;
}


// Generate PDU formatted cellphone number
private function getNumberAsPDU($number) {

        // Length of number divided by 2 handle two characters each time
    $length = strlen( $number )/2;
    // Set counter to 1 for strlen
    $i = 1;
    $pduNumber = '';

    // Loop to handle every 2 characters of the phone number. 06 12 34 56 78
    while ($i <= $length) {
        // Get 2 characters of the complete string depending on the number of the current loop.
        // Then reverse these 2 characters and put them in var $pduNumber (06 = 60)
        $pduNumber .= strrev( substr( $number,$i*2-2,2) );
        // Counter + 1
        $i++;
    }

    // Return the generated number
    return $pduNumber;
}


/* Function to convert ascii character to 8 bits
 * Much more efficient than holding a complete ASCII table
 * Thanks to Mattijs F.
 */
private function asc2bin($input, $length=8) {

    $bin_out = '';
    // Loop through every character in the string
    for($charCount=0; $charCount < strlen($input); $charCount++) {
        $charAscii = ord($input{$charCount}); // ascii value of character
        $charBinary = decbin($charAscii); // decimal to binary
        $charBinary = str_pad($charBinary, $length, '0', STR_PAD_LEFT);
        $bin_out .= $charBinary;
    }

    // Return complete generated string
    return $bin_out;
}


// String to 7 bits array
private function strto7bit($message) {
    $message = trim($message);
    $length = strlen( $message );
    $i = 1;
    $bitArray = array();

    // Loop through every character in the string
    while ($i <= $length) {
        // Convert this character to a 7 bits value and insert it into the array
        $bitArray[] = $this->asc2bin( substr( $message ,$i-1,1) ,7);
        $i++;
    }


    // Return array containing 7 bits values
    return $bitArray;
}


// Convert 8 bits binary string to hex values (like F2)
private function bit8tohex($bin, $padding=false, $uppercase=true) {
    $hex = '';
    // Last item for counter (for-loop)
    $last = strlen($bin)-1;
    // Loop for every item
    for($i=0; $i<=$last; $i++) {
        $hex += $bin[$last-$i] * pow(2,$i);
    }

    // Convert from decimal to hexadecimal
    $hex = dechex($hex);
    // Add a 0 (zero) if there is only 1 value returned, like 'F'
    if($padding && strlen($hex) < 2 ) {
        $hex = '0'.$hex;
    }

    // If we want the output returned as UPPERCASE do this
    if($uppercase) {
        $hex = strtoupper($hex);
    }

    // Return the hexadecimal value
    return $hex;
}


// Convert 7 bits binary to hex, 7 bits > 8 bits > hex
private function bit7tohex($bits) {

    $i = 0;
    $hexOutput = '';
    $running = true;

    // For every 7 bits character array item
    while($running) {

        if(count($bits)==$i+1) {
            $running = false;
        }

        $value = $bits[$i];

        if($value=='') {
            $i++;
            continue;
        }

        // Convert the 7 bits value to the 8 bits value
        // Merge a part of the next array element and a part of the current one

        // Default: new value is current value
        $new = $value;

        if(key_exists(($i+1), $bits)) {
            // There is a next array item so make it 8 bits
            $neededChar = 8 - strlen($value);
            // Get the char;s from the next array item
            $charFromNext = substr($bits[$i+1], -$neededChar);
            // Remove used bit's from next array item
            $bits[$i+1] = substr($bits[$i+1], 0, strlen($bits[$i+1])-$neededChar );
            // New value is characters from next value and current value
            $new = $charFromNext.$value;
        }

        if($new!='') {
            // Always make 8 bits
            $new = str_pad($new, 8, '0', STR_PAD_LEFT);
            // The 8 bits to hex conversion
            $hexOutput .= $this->bit8tohex($new, true);
        }

        $i++;
    }

    // Return the 7bits->8bits->hexadecimal generated value
    return $hexOutput;
}

// String to length in Hex, String > StringLength > Hex
private function strToHexLen($message) {

    // Length of the string (message)
    $length = strlen( $message )+7; //+7 for UDH. the UDH is a total of (number of octets x bit size of octets) 6 x 8 = 48 bits long. Therefore a single bit of padding has to be prepended to the message. The UDH is therefore (bits for UDH / bits per septet) = (48 + 1)/7 = 7 septets in length.
    // Hex value of this string length
    $hex = dechex($length);

    // Length of the hex value
    $hexLength = strlen($hex);
    // If the hex strng length is lower dan 2
    if($hexLength < 2) {
        // Add a 0 (zero) before it
        $hex = '0'.$hex;
    }

    // Return the hex value in UPPERCASE characters
    return strtoupper($hex);
}

}
?>

2 个答案:

答案 0 :(得分:3)

如您所知,创建连续的SMS消息需要您在短信之前添加UDH。 UDH成为有效负载的一部分,从而减少了每个段可以发送的字符数。

由于它已成为您的有效负载的一部分,因此需要确认您的有效负载数据要求 - 即7位。然而,UDH是8位,这显然使事情变得复杂。

考虑以下的UDH:

050003000302
  • 05是UDH的长度
  • 00是IEI
  • 03是IEDL(3个以上的八位字节)
  • 00是一个引用(这个数字在每个连接的消息UDH中必须相同)
  • 03是最大消息数
  • 02是当前的消息编号。

这总共是6个八位字节 - 相当于48位。这一切都很好,但由于UDH实际上是SMS消息的一部分,您需要做的是添加更多位,以便实际消息在septet边界上开始。 septet边界是每7位,所以在这种情况下,我们将需要再添加1位数据以使UDH为49位,然后我们可以添加标准的GSM-7编码字符。

您可以从Here

了解更多相关信息

答案 1 :(得分:0)

这些问题到处都是,似乎没有人能够以任何有意义的方式回答它们。零填充通常只会让事情变得更糟。我认为解决GMS标准中这个设计缺陷的最简单方法是使用8位编码或16位UCS2,即使它意味着更少的字符。通过这种方式,您不需要关心字节边界的差异,这就是创建串联SMS非常困难的原因。