SSL証明書の有効期限をチェックして、アラートメールで通知【PHP】

SSL証明書の有効期限チェックを zabbixに入れこもうと思ったんですが、

Zabbixだと設定が面倒だなということで、お手軽なバッチをPHPで作りました。

URLリストをただ追加していけばいい形です。
この方が運用が楽だなと。もしよければ　ご利用ください。

<?php
//================================================
// Setting
//================================================
//Alert mail
$toMail   = 'to@example.com';
$fromMail = 'from@example.com';

//Target Before
$before = 14;

//Target URL
$list = <<<END
https://www.example.com/
https://sub.example.com/
END;
//================================================

$urls = explode("\n",$list);
$alert = false;
$beforeDate = date('Y-m-d',strtotime($before .' day'));

foreach($urls as $url){
    $orignal_parse = parse_url(trim($url), PHP_URL_HOST);
    $get = stream_context_create(array("ssl" => array("capture_peer_cert" => TRUE)));
    $read = stream_socket_client("ssl://".$orignal_parse.":443", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $get);
    $cert = stream_context_get_params($read);
    $certinfo = openssl_x509_parse($cert['options']['ssl']['peer_certificate']);
    $valid_to = date("Y-m-d",$certinfo['validTo_time_t']);
    $status = "{$url} : {$valid_to}\n";
    echo($status);
    if($valid_to < $before_date){
        $alert .= $status;
    }
}
if($alert){
    $body = "SSL expiration {$before} days ago \n\n" .$alert;
    mb_send_mail($to_mail,'【Alert】SSL expiration',$body,"From: {$fromMail}");
}
?>

<?php

//================================================

// Setting

//================================================

//Alert mail

$toMail = 'to@example.com';

$fromMail = 'from@example.com';

//Target Before

$before = 14;

//Target URL

$list = <<<END

https://www.example.com/

https://sub.example.com/

END;

//================================================

$urls = explode("\n",$list);

$alert = false;

$beforeDate = date('Y-m-d',strtotime($before .' day'));

foreach($urls as $url){

$orignal_parse = parse_url(trim($url), PHP_URL_HOST);

$get = stream_context_create(array("ssl" => array("capture_peer_cert" => TRUE)));

$read = stream_socket_client("ssl://".$orignal_parse.":443", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $get);

$cert = stream_context_get_params($read);

$certinfo = openssl_x509_parse($cert['options']['ssl']['peer_certificate']);

$valid_to = date("Y-m-d",$certinfo['validTo_time_t']);

$status = "{$url} : {$valid_to}\n";

echo($status);

if($valid_to < $before_date){

$alert .= $status;

}

if($alert){

$body = "SSL expiration {$before} days ago \n\n" .$alert;

mb_send_mail($to_mail,'【Alert】SSL expiration',$body,"From: {$fromMail}");

}

エラー

error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed

というエラーが出る場合は、サーバー側のCA証明書が古い可能性があるので、確認しましょう。