websocket.php

#!/usr/bin/env php
<?php

$port = isset($argv[1]) && intval($argv[1]) ? $argv[1] : 8888;

$sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

socket_bind($sock, '127.0.0.1', $port);
socket_listen($sock);

$handshaked = false;

while ($c = socket_accept($sock)) {
    while ($rec = socket_read($c, 4096)) {
        if (!$handshaked) {
            $heads = read_handshake($rec);
            socket_write($c, res_handshake($heads));
            $handshaked = true;
        } else {
            $str = decode_bin($rec);
            echo $str . "\n";
            socket_write($c, encode("received [". $str . "]"));
        }
    }
}
socket_close($sock);


function read_handshake($header)
{
    foreach (explode("\n", $header) as $line) {
        $head = explode(':', $line);
        if (count($head) > 1) {
            $ret[trim($head[0])] = trim($head[1]);
        }
    }
    return $ret;
}

function res_handshake($heads)
{
    $accept = base64_encode(sha1($heads['Sec-WebSocket-Key'].'258EAFA5-E914-47DA-95CA-C5AB0DC85B11', true));
    ;
    $header  = "HTTP/1.1 101 Switching Protocols\r\n";
    $header .= "Upgrade: websocket\r\n";
    $header .= "Connection: Upgrade\r\n";
    $header .= "Sec-WebSocket-Accept: $accept\r\n";
    $header .= "\r\n";
    return $header;
}

function decode_bin($data)
{
    $res = '';
    $offset = 6;
    $mask = substr($data, 2, 4);
    $payloadlength = ord($data[1]) &127;
    $length = $payloadlength + $offset;

    for ($i=$offset; $i<$length; $i++) {
        $j = $i - $offset;
        $res .= $data[$i] ^ $mask[$j % 4];
    }
    return $res;
}


function encode($text)
{
    $head = [];
    $head[0] = chr(129);
    $head[1] = chr(strlen($text) + 128);
    for ($i=0; $i<4; $i++) {
        $mask[$i] = chr(rand(0, 255));
    }
    $head = array_merge($head, $mask);
    $frame = implode('', $head);

    for ($i=0; $i<strlen($text); $i++) {
        $frame .= $text[$i] ^ $mask[$i % 4];
    }
    return $frame;
}