Client delivery report about whatsapi

[cdesjardins]

If someone could just make an unencrypted/decrypted capture of the client delivery report message from the recipient phone to the whatsapp server and send it to me then I will write the code myself. Or if someone knows a good way to capture the data myself, I will do my own captures as well. Unfortunately I have not figured out a way to sniff whatsup traffic from real phones or emulators.
Thanks!

[xTraXx]

Don't know if there is something like wireshark for iPhone?

[cdesjardins]

I am using android and I have run TCPdump on my phone already, but all of the messages of interest are encrypted.

[cdesjardins]

I finally figured it out, for the client delivery message, the format is as follows:
0x00, [total msg length], 0xf8, 0x08, 0x5d, 0xa0, 0xfa, 0xfc, [Number Length], [UTF8 to number], 0x8a, 0xa2, 0x1b, 0x43, 0xfc, [id length], [UTF8 msg ID], 0xf8, 0x01, 0xf8, 0x03, 0x7f, 0xbd, 0xad,

Where the UTF8 to number is the phone number that you are responding to, and the UTF8 message ID is the same message ID that you are responding to. Unfortunately I do not have time to code this up right now, but I thought I would post this info along in case someone else wants to add it.

[xTraXx]

Are you sure this is correct? (I can't get it to work)

[cdesjardins]

Yup, here is a full dump:

0x00, 0x2c, 0xf8, 0x08, 0x5d, 0xa0, 0xfa, 0xfc, 0x0b, 0x31, 0x39, 0x31, 0x39, 0x31, 0x32, 0x33,   .,..]....1919123
0x34, 0x35, 0x36, 0x37, 0x8a, 0xa2, 0x1b, 0x43, 0xfc, 0x0d, 0x31, 0x31, 0x31, 0x32, 0x32, 0x32,   4567...C..111222
0x33, 0x33, 0x33, 0x33, 0x2d, 0x31, 0x30, 0xf8, 0x01, 0xf8, 0x03, 0x7f, 0xbd, 0xad,               3333-10....⌂..

Where 19191234567 is the phone number that I want to send the ack to, and 1112223333-10 is the message ID from the message that person just sent me. I have a test project in c# that does this and I get the double check marks every time. I cannot post the code unfortunately.

[xTraXx]

Oke, then I'll try again.

[xTraXx]

function MessageReceived($msg_length,$to_length,$to,$msgid_length,$msgid){
$content = "\x00$msg_length";
$content .= "\xf8\x08\x5d\xa0\xfa\xfc$to_length";
$content .=$to;
$content .= "x8a\xa2\x1b\x43\xfc$msgid_length";
$content .= $msgid;
$content .= "\xf8\x01\xf8\x03\x7f\xbd\xad";
$this->send($content);
}

What am I doing wrong? (Normally I don't work with php, so maybe a dumb mistake?)

[cdesjardins]

I think you are doing the lengths wrong, for example the msg_length is typically computed like this:

$msg_length = hex2str(_hex(strlen($content)));

There are also some places where they do this:

$to_length = chr(mb_strlen($to,"UTF-8"));

It is not clear if you are doing that or not.

Here is a function I wrote to debug this type of stuff:

public function printhexstr($data, $name)
{
    $len = strlen($data);
    print("Len: $len - $name\n");
    for ($i = 0; $i < $len; $i++)
    {
        print(" ". dechex(ord($data[$i])));
        if (($i % 16) == 15)
        {
            print("\n");
        }
    }
    print("\n");
}

To see what you are really sending just call:

printhexstr($context, "message rx");

[xTraXx]

I just took the length which I receive.

$msg = $this->parse_received_message($v);
echo json_encode($msg); // Do something with the message here ?

    $this->MessageReceived($msg['length'],$msg['from_number_length'],$msg['from_number'],$msg['message_id_length'],$msg['message_id']);

[cdesjardins]

OK, I just pushed the php up in my fork, feel free to merge it wherever.

[xTraXx]

Thx, it's working now :D

[cdesjardins]

Just for the record, the issues were:
On one line you didn't have x8a escaped.
The message length is supposed to be the message length of the message you are sending, not the one you are acking.

[xTraXx]

Oh oke, I see hehe.

[xTraXx]

BTW, did you port this API to C# or do you use this API (PHP) with C#?

[eslamo]

Hello,

Can u please provide us with the full php code to add into our file and get it working ..