给同事做了个 PHP 接口，转发发送短信的请求，同时要把发送记录发送到远程的 cacti 的 syslog 去

很简单，但是也不简单

首先是 PHP 服务器，是最简化编译的，php -m 查了一下

php -m
[PHP Modules]
Core
ctype
curl
date
dom
fileinfo
filter
gettext
hash
iconv
json
libxml
openssl
pcre
PDO
pdo_sqlite
Phar
posix
Reflection
session
SimpleXML
SPL
sqlite3
standard
tokenizer
xml
xmlreader
xmlwriter

[Zend Modules]

居然没有 socket 模块，没办法，找到源代码，编译一个安装，原有的 php 安装路径是 /export/servers/php

$ tar zxvf php-7.4.0.tar.gz 
$ cd php-7.4.0/sockets
$ /export/servers/php/bin/phpize
$ ./configure --enable-sockets --with-php-config=/export/servers/php/bin/php-config
$ make
$ make install

又看了一眼，是 php-fpm，居然没有 php.ini ，得，再生成一个，放在 /export/servers/php/lib/php.ini

extension_dir = "/export/servers/php740/lib/php/extensions/no-debug-non-zts-20190902/"
extension = sockets.so

然后重启 php-fpm ，重新 php -m 检查，发现有 socket 模块就 ok 了。

接下来就是 php 源代码了

<?php
date_default_timezone_set('Asia/Shanghai');

function send_remote_syslog($message) {
    $sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
    foreach(explode("\n", $message) as $line) {
      $syslog_message = "<22>" . date('M d H:i:s ') . 'Qi_an_xin sms_log: ' . $line;
      socket_sendto($sock, $syslog_message, strlen($syslog_message), 0, '172.18.31.6', 514);
    }
    socket_close($sock);
}

    send_remote_syslog("ABC 验证码: 39792192");
?>

这样就可以了，上面代码比较难理解的是<22>，那是报错级别的计算方法，Facility + Severity：

 *   Facility values:
 *      0 kernel messages
 *      1 user-level messages
 *      2 mail system
 *      3 system daemons
 *      4 security/authorization messages
 *      5 messages generated internally by syslogd
 *      6 line printer subsystem
 *      7 network news subsystem
 *      8 UUCP subsystem
 *      9 clock daemon
 *     10 security/authorization messages
 *     11 FTP daemon
 *     12 NTP subsystem
 *     13 log audit
 *     14 log alert
 *     15 clock daemon
 *     16 local user 0 (local0) (default value)
 *     17 local user 1 (local1)
 *     18 local user 2 (local2)
 *     19 local user 3 (local3)
 *     20 local user 4 (local4)
 *     21 local user 5 (local5)
 *     22 local user 6 (local6)
 *     23 local user 7 (local7)
 *
 *   Severity values:
 *     0 Emergency: system is unusable
 *     1 Alert: action must be taken immediately
 *     2 Critical: critical conditions
 *     3 Error: error conditions
 *     4 Warning: warning conditions
 *     5 Notice: normal but significant condition (default value)
 *     6 Informational: informational messages
 *     7 Debug: debug-level messages

计算方法就是 （facility*8 + severity），这里的22+0，可以理解成 local6 ，就是级别6

image-20211028114512589

如果发了一个 “local use 4” 和 Serverity = 5 的消息，那么就是 20×8+5=165 ，包头就是 <165>