无法使用 PHP shell_exec() 执行 telnet 命令

Question

我正在尝试使用 telnet 和 php 进行邮件验证。整个过程在terminal里没问题，但是当我使用php shell_exec()时，它只运行到Telnet连接命令。连接 telnet 后，其余的 telnet 特定命令将不再起作用。

是否有其他方法需要我们使用 php 执行 telnet？

更新：我正在尝试复制 this 教程。

这是我的代码

public function mailtest(Request $request){
        //Taking input email
        $email = $request->input("email");
        $divide = explode("@", $email);
        //Find out the Domain
        $server = $divide[1];
        $response = shell_exec("nslookup -q=mx $server");
        //Response of the nslookup
        print_r($response);
        $mailServerList = explode(PHP_EOL, $response);
        $line = $mailServerList[4];

        $serverArr = preg_split('/\s+/', $line);
        $n = sizeof($serverArr);
        $mailServer = $serverArr[$n-1];
        //Printing out the mail server out of the nslookup response
        print_r($mailServer);
        //Executing Telnet command
        $telnet = shell_exec("telnet $mailServer 25");
        print_r("telnet response ".$telnet);

        //Telnet Helo
        $helo = shell_exec("Helo testing.com");
        print_r("Helo response ".$helo);
        //Telnet mail from 
        $from = shell_exec('mail from: testing@gmail.com');
        print_r("MAil from response ".$from);
        //Telnet RCPT to
        $finalResponse = shell_exec("rcpt to: $email");
        print_r("Mail to response ".$finalResponse);
    }

这是回复

Server:     10.0.80.11
Address:    10.0.80.11#53

Non-authoritative answer:
gmail.com   mail exchanger = 5 gmail-smtp-in.l.google.com.
gmail.com   mail exchanger = 10 alt1.gmail-smtp-in.l.google.com.
gmail.com   mail exchanger = 40 alt4.gmail-smtp-in.l.google.com.
gmail.com   mail exchanger = 30 alt3.gmail-smtp-in.l.google.com.
gmail.com   mail exchanger = 20 alt2.gmail-smtp-in.l.google.com.

Authoritative answers can be found from:
gmail-smtp-in.l.google.com  internet address = 173.194.64.27
gmail-smtp-in.l.google.com  has AAAA address 2607:f8b0:4003:c02::1a
alt1.gmail-smtp-in.l.google.com internet address = 173.194.219.27
alt1.gmail-smtp-in.l.google.com has AAAA address 2607:f8b0:4002:c03::1b
alt4.gmail-smtp-in.l.google.com internet address = 64.233.190.26
alt4.gmail-smtp-in.l.google.com has AAAA address 2800:3f0:4003:c01::1b
alt3.gmail-smtp-in.l.google.com internet address = 74.125.141.26
alt3.gmail-smtp-in.l.google.com has AAAA address 2607:f8b0:400c:c06::1a
alt2.gmail-smtp-in.l.google.com internet address = 173.194.205.27
alt2.gmail-smtp-in.l.google.com has AAAA address 2607:f8b0:400d:c02::1b

gmail-smtp-in.l.google.com.telnet response Trying 2607:f8b0:4003:c02::1a...
Connected to gmail-smtp-in.l.google.com.
Escape character is '^]'.
Helo response 
MAil from response No message, no subject; hope that's ok
Mail to response

Answer 1

shell_exec() 开始一个新进程。它首先启动一个 shell ，然后将给定的字符串作为命令执行。您不能使用多个 shell_exec() 命令与同一个 shell 进行交互，例如远程控制终端。

对于你的情况，我会做的是尝试在现有代码的基础上构建。比如现有一堆PHP SMTP libraries。我很确定他们中至少有一个能够做你想做的事，或者至少向你展示一种实现缺失功能的方法。

如果您真的坚持自己动手，请查看现有答案，例如interacting with command line program or PHP's expect module。除非绝对需要，否则我会避免这样做，因为它效率低下。此外，出于安全原因，网络服务器通常被配置为不允许启动新进程，因此如果您的代码在您运行从命令行而不是在网络服务器内部运行时有效，请记住这一差异。

Answer 2

shell_exec 不适合（参见 Ulrich 的解释）。

fsockopen 应该可以解决问题。

$fp = @fsockopen('yourMailServer.com', 9001);      

if ($fp) { 
    fwrite($fp, "username\n");
    fwrite($fp, "password\n");

    while ($line = fread($fp, 2048)) {    
       // do things with $line    
    }    
} else {    
    //return error    
}

Answer 3

在参考了@Lavi 的回答后，我就是这样解决问题的。 fputs 成功了，而不是 fwrite

$connect = @fsockopen($mailServer, 25);
if($connect){
    fputs ($connect , "HELO $mailServer\r\n");
    $out = fgets ($connect, 1024);
    $details .= $out."\n";

    fputs ($connect , "MAIL FROM: <$fromemail>\r\n");
    //$from = fgets ($connect, 1024);
    fputs ($connect , "RCPT TO: <$toemail>\r\n");
    //$to = fgets ($connect, 1024);
    fputs ($connect , "QUIT");
    fclose($connect);
}

无法使用 PHP shell_exec() 执行 telnet 命令

Cannot execute telnet commands using PHP shell_exec()

php

networking

telnet

shell-exec

email-validation