Question

为什么以下正则表达式与以下文本不匹配？

正则表达式：

\[\]\s\[(:?error|\S+:\S+)\]( \[pid \d+(:\S+ \d+)?\])? \[client <HOST>(:\d{1,5})?\] ModSecurity:\s+(?:\[(?:\w+ \"[^\"]*\"|[^\]]*)\]\s*)*Access denied with code [45]\d\d

测试字符串：

[Sun Mar 15 22:28:19.733272 2018] [:error] [pid 11954] [client 188.191.122.27:62165] [client 188.191.122.27] ModSecurity: Access denied with code 403 (phase 2). Operator GE matched 4 at TX:anomaly_score. [file ".../modsecurity.d/owasp-modsecurity-crs/rules/REQUEST-949-BLOCKING-EVALUATION.conf"] [line "57"] [id "949110"] [msg "Inbound Anomaly Score Exceeded (Total Score: 5)"] [severity "CRITICAL"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-generic"] [hostname "63.60.128.135"] [uri "/phpmyadmin/phpmyadmin/index.php"] [unique_id "W0uuY3C8AA4EAA5OC7wBAAAH"]

这是来自fail2ban的预定义规则和具有更改地址的随机apache日志条目。

起初，我认为错误是客户端被两次登录，所以我更改了客户端行：

(\[client <HOST>(:\d{1,5})?\])+

但这似乎也不起作用。

只是要弄清楚一切：

 Regular expressions (failregex, ignoreregex) assume that the date/time has been removed from the log line (this is just how fail2ban works internally ATM).

 If the format is like „<date...> error 1.2.3.4 is evil“ then you need to match the < at the start so regex should be similar to „^<> <HOST> is evil$„ using <HOST> where the IP/domain name appears in the log line.

（摘自fail2ban文档：https://fail2ban.readthedocs.io/en/latest/filters.html）（我将其写为代码是因为stackoverflow似乎在用引号引起来的特定字符方面存在问题。）

我对正则表达式或多或少是新的，所以感谢您的帮助。

Answer 1

你很近。当您为多个客户端添加重复组时，您没有在其中包含将其分隔的空格。

\[\]\s\[(:?error|\S+:\S+)\]( \[pid \d+(:\S+ \d+)?\])?( \[client <HOST>(:\d{1,5})?\])+ ModSecurity:\s+(?:\[(?:\w+ \"[^\"]*\"|[^\]]*)\]\s*)*Access denied with code [45]\d\d

DEMO

正则表达式与测试字符串不匹配

1 个答案: