Detailed analysis and problem summary of php using curl

PHP supports libcurl, a library created by Daniel Stenberg, that allows you to connect and communicate to many different types of servers with many different types of protocols. libcurl currently supports the http, https, ftp, gopher, telnet, dict, file, and ldap protocols. libcurl also supports HTTPS certificates, HTTP POST, HTTP PUT, FTP uploading (this can also be done with PHP's ftp extension), HTTP form based upload, proxies, cookies, and user+password authentication.

<?php

  // create curl resource

  $ch = curl_init();

  // set url

  curl_setopt($ch, CURLOPT_URL, "baidu.com");

  //return the transfer as a string

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  // $output contains the output string

  $output = curl_exec($ch);

  //echo output

  echo $output;

  // close curl resource to free up system resources

  curl_close($ch);  

?>

//通过curl进行GET请求的案例

<?php

  // create curl resource

  $ch = curl_init();

  // set url

  curl_setopt($ch, CURLOPT_URL, "https://github.com/search?q=react");

  //return the transfer as a string

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  // $output contains the output string

  $output = curl_exec($ch);

  //echo output

  echo $output;

  // close curl resource to free up system resources

  curl_close($ch);  

?>

The two Curl options are defined as:

CURLOPT_SSL_VERIFYPEER - verify the peer's SSL certificate 

CURLOPT_SSL_VERIFYHOST - verify the certificate's name against host

They both default to true in Curl, and shouldn't be disabled unless you've got a good reason. Disabling them is generally only needed if you're sending requests to servers with invalid or self-signed certificates, which is only usually an issue in development. Any publicly-facing site should be presenting a valid certificate, and by disabling these options you're potentially opening yourself up to security issues.

//testRespond.php

<?php

  $phpInput=file_get_contents('php://input');

  echo urldecode($phpInput);

?>

<?php

  $data=array(

  "name" => "Lei",

  "msg" => "Are you OK?"

  );

  $ch = curl_init();

  curl_setopt($ch, CURLOPT_URL, "http://测试服务器的IP马赛克/testRespond.php");

  curl_setopt($ch, CURLOPT_POST, 1);

  //The number of seconds to wait while trying to connect. Use 0 to wait indefinitely.

  curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);

  curl_setopt($ch, CURLOPT_POSTFIELDS , http_build_query($data));

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  $output = curl_exec($ch);

  echo $output;

  curl_close($ch);  

?>

<?php

  $data='{"name":"Lei","msg":"Are you OK?"}';

  $ch = curl_init();

  curl_setopt($ch, CURLOPT_URL, "http://测试服务器的IP马赛克/testRespond.php");

  curl_setopt($ch, CURLOPT_POST, 1);

  curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);

  curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json', 'Content-Length:' . strlen($data)));

  curl_setopt($ch, CURLOPT_POSTFIELDS , $data);

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  $output = curl_exec($ch);

  echo $output;

  curl_close($ch);  

?>

<?php

  if($_FILES){

    $filename = $_FILES['upload']['name'];

     $tmpname = $_FILES['upload']['tmp_name'];

     //保存图片到当前脚本所在目录

     if(move_uploaded_file($tmpname,dirname(__FILE__).'/'.$filename)){

      echo ('上传成功');

     }

  }

?>

<?php

  $data = array('name'=>'boy', "upload"=>"@boy.png");

  $ch = curl_init();

  curl_setopt($ch, CURLOPT_URL, "http://远程服务器地址马赛克/testRespond.php");

  curl_setopt($ch, CURLOPT_POST, 1);

  curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);

  curl_setopt($ch, CURLOPT_POSTFIELDS , $data);

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  $output = curl_exec($ch);

  echo $output;

  curl_close($ch);    

?>

<?php

  $data = array('name'=>'boy', "upload"=>"");

  $ch = curl_init();

  $data['upload']=new CURLFile(realpath(getcwd().'/boy.png'));

  curl_setopt($ch, CURLOPT_URL, "http://115.29.247.189/test/testRespond.php");

  curl_setopt($ch, CURLOPT_POST, 1);

  curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);

  curl_setopt($ch, CURLOPT_POSTFIELDS , $data);

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  $output = curl_exec($ch);

  echo $output;

  curl_close($ch);    

?>

<?php

  $ch = curl_init();

  $fp=fopen('./girl.jpg', 'w');

  curl_setopt($ch, CURLOPT_URL, "http://远程服务器地址马赛克/girl.jpg");

  curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);

  curl_setopt($ch, CURLOPT_FILE, $fp);

  $output = curl_exec($ch);

  $info = curl_getinfo($ch);

  fclose($fp);

  $size = filesize("./girl.jpg");

  if ($size != $info['size_download']) {

    echo "下载的数据不完整，请重新下载";

  } else {

    echo "下载数据完整";

  }

  curl_close($ch); 

?>

function curl_auth($url,$user,$passwd){

  $ch = curl_init();

  curl_setopt_array($ch, [

    CURLOPT_USERPWD => $user.':'.$passwd,

    CURLOPT_URL   => $url,

    CURLOPT_RETURNTRANSFER => true

  ]);

  $result = curl_exec($ch);

  curl_close($ch);

  return $result;

}

$authurl = 'http://要请求HTTP认证的地址';

echo curl_auth($authurl,'vace','passwd');

这里有一个地方比较有意思：

curl_setopt_array 这个方法可以通过数组一次性地设置多个参数，防止有些需要多处设置的出现密密麻麻的curl_setopt方法。

5.利用cookie模拟登陆

这时你成功见到了服务器妹子，想带她私奔，但是无奈没有盘缠走不远，服务器妹子说，她妈服务器上有金库，可以登陆上去搞一点下来。

首先我们先来分析一下，这个事情分两步，一是去登陆界面通过账号密码登陆，然后获取cookie，二是去利用cookie模拟登陆到信息页面获取信息，大致的框架是这样的。

<?php

 //设置post的数据

 $post = array (

  'email' => '账户',

  'pwd' => '密码'

 );

 //登录地址

 $url = "登陆地址";

 //设置cookie保存路径

 $cookie = dirname(__FILE__) . '/cookie.txt';

 //登录后要获取信息的地址

 $url2 = "登陆后要获取信息的地址";

 //模拟登录

 login_post($url, $cookie, $post);

 //获取登录页的信息

 $content = get_content($url2, $cookie);

 //删除cookie文件

 @ unlink($cookie);

 var_dump($content); 

?>

login_post($url, $cookie, $post)

get_content($url2, $cookie)

//模拟登录

function login_post($url, $cookie, $post) {

  $curl = curl_init();

  curl_setopt($curl, CURLOPT_URL, $url);

  curl_setopt($curl, CURLOPT_RETURNTRANSFER, 0);

  curl_setopt($curl, CURLOPT_COOKIEJAR, $cookie);

  curl_setopt($curl, CURLOPT_POST, 1);

  curl_setopt($curl, CURLOPT_POSTFIELDS, http_build_query($post));

  curl_exec($curl);

  curl_close($curl);

}

//登录成功后获取数据

function get_content($url, $cookie) {

  $ch = curl_init();

  curl_setopt($ch, CURLOPT_URL, $url);

  curl_setopt($ch, CURLOPT_HEADER, 0);

  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

  curl_setopt($ch, CURLOPT_COOKIEFILE, $cookie);

  $rs = curl_exec($ch);

  curl_close($ch);

  return $rs;

}