本质上实现组装http信息的请求行，头信息，主题信息，参考it自学网

cookie信息和http请求头有很大关系，注意把http请求头信息传递到函数里面

01-msg.php

<?php

require('./http.class.php');


$http = new Http('http://home.verycd.com/cp.php?ac=pm&op=send&touid=0&pmid=0');


$http->setHeader('Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8');
$http->setHeader('Accept-Encoding: gzip, deflate');
$http->setHeader('Accept-Language: zh-cn,zh;q=0.8,en-us;q=0.5,en;q=0.3');
$http->setHeader('Connection: keep-alive');

$http->setHeader('Cookie: Hm_lvt_c7849bb40e146a37d411700cb7696e46=1371132935,1371551596,1371552570; CNZZDATA1479=cnzz_eid%3D2070887527-1371133011-http%253A%252F%252Fhome.verycd.com%26ntime%3D1371559611%26cnzz_a%3D27%26retime%3D1371559611556%26sin%3Dhttp%253A%252F%252Fwww.verycd.com%252Fi%252F17907141%252F%26ltime%3D1371559611556%26rtime%3D1; __utma=248211998.1671623420.1371133015.1371557486.1371559612.4; __utmz=248211998.1371552579.2.2.utmcsr=verycd.com|utmccn=(referral)|utmcmd=referral|utmcct=/; Hm_lpvt_c7849bb40e146a37d411700cb7696e46=1371554752; post_action=repost; BAIDU_CLB_REFER=http%3A%2F%2Fcwebmail.mail.163.com%2Fjs5%2Fread%2Freadhtml.jsp%3Fssid%3DI7zQECYCxLDKHPlnXYxQm9sNe5EPh1drYPvN26nZekk%253d%26mid%3D45%3A1tbiLRFAhFEFoLvtCAAAsS%26color%3D003399%26preventSetRead%3Don%26font%3D15; uchome_loginuser=http%E5%8D%8F%E8%AE%AE; uchome__refer=%2Fspace.php%3Fdo%3Dpm%26filter%3Dnewpm; __utmc=248211998; sid=9a48b201fb4d176a7188ef2a3560789651eb4766; member_id=17822047; member_name=http%E5%8D%8F%E8%AE%AE; mgroupId=93; pass_hash=e75f942862a5e927a2faffd2d2d582c9; rememberme=false; uchome_auth=4128oUJWyonkCXZvxM4sDRjcugSmt3L0r197Pq%2BPdf8fcLJsUiNZKBXjG0hYuPZSRK3XEs2FuRn1pH2cEFBNc1H0Im7x5A; uchome_sendmail=1; uchome_checkpm=1; __utmb=248211998.1.10.1371559612; dcm=1');

$http->setHeader('Referer: http://home.verycd.com/cp.php?ac=pm');
$http->setHeader('User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0');


$msg = array(
'formhash'=>'4f23e777',
'message'=>'我不是在灌水,请放行',
'pmsubmit'=>'true',
'pmsubmit_btn'=>'发送',
'refer'=>'http://home.verycd.com/space.php?do=pm&filter=privatepm',
'username'=>'http接收'
);


file_put_contents('./res.html',$http->post($msg));
echo 'ok';

<?php
/*
PHP+socket编程　发送HTTP请求

要求能　模拟下载，注册，登陆,批量发帖
*/


// http请求类的接口
interface Proto {
    // 连接url
    function conn($url);

    //发送get查询
    function get();

    // 发送post查询
    function post();

    // 关闭连接
    function close();
}



class Http implements Proto {

    const CRLF  = "\r\n";

    protected $errno = -1;
    protected $errstr = '';
    protected $response = '';

    protected $url = null;
    protected $version = 'HTTP/1.1';
    protected $fh = null;
    
    protected $line = array();
    protected $header = array();
    protected $body = array();

    
    public function __construct($url) {
        $this->conn($url);
        $this->setHeader('Host: ' . $this->url['host']);
    }

    // 此方法负责写请求行
    protected function setLine($method) {
        $this->line[0] = $method . ' ' . $this->url['path'] . '?' .$this->url['query'] . ' '. $this->version;
    }

    // 此方法负责写头信息
    public function setHeader($headerline) {
        $this->header[] = $headerline; 
    }

    // 此方法负责写主体信息
    protected function setBody($body) {
         $this->body[] = http_build_query($body);
    }


    // 连接url
    public function conn($url) {
        $this->url = parse_url($url);
        //　判断端口
        if(!isset($this->url['port'])) {
            $this->url['port'] = 80;
        }

        //　判断query
        if(!isset($this->url['query'])) {
            $this->url['query'] = '';
        }

        $this->fh = fsockopen($this->url['host'],$this->url['port'],$this->errno,$this->errstr,3);
    }

    //构造get请求的数据
    public function get() {
        $this->setLine('GET');
        $this->request();
        return $this->response;
    }

    // 构造post查询的数据
    public function post($body = array()) {      
        $this->setLine('POST');

        // 设计content-type
        $this->setHeader('Content-type: application/x-www-form-urlencoded');
        
        // 设计主体信息,比GET不一样的地方
        $this->setBody($body);


        // 计算content-length
        $this->setHeader('Content-length: ' . strlen($this->body[0]));

        $this->request();

        return $this->response;
    }

    // 真正请求
    public function request() {
        // 把请求行，头信息，实体信息　放在一个数组里，便于拼接
        $req = array_merge($this->line,$this->header,array(''),$this->body,array(''));
        //print_r($req);

        $req = implode(self::CRLF,$req); 
        //echo $req; exit;

        fwrite($this->fh,$req);
        
        while(!feof($this->fh)) {
            $this->response .= fread($this->fh,1024);
        }

        $this->close(); //　关闭连接
    }


    // 关闭连接
    public function close() {
        fclose($this->fh);
    }

    

}




/*
$url = 'http://news.163.com/13/0613/09/9187CJ4C00014JB6.html';

$http = new Http($url);
echo $http->get();
*/
/*
set_time_limit(0);

$url = 'http://liangyue.net.cn/0523/?';



for($i=1;$i<100;$i++) {
    $str = str_shuffle('abcdefghijklmnopqrst0776656');
    $tit = substr($str,0,5);
    $con = substr($str,6,8);

    $http = new Http($url);
    $http->post(array('tit'=>$tit,'con'=>$con,'submit'=>'留言'));

    echo $tit,'-----------',$con,'<br />';

    usleep(2000);
}

*/

PHP + Socket 发送http请求进而实现网站灌水