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DOC: corrections and enhancements on DEVELOP

pull/361/head
Daniel Black 2013-09-22 16:23:04 +10:00
parent 2562b2f1bc
commit ca496f6d41
1 changed files with 16 additions and 6 deletions
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@ -41,10 +41,14 @@ Filters are tricky. They need to:
* work with a variety of the versions of the software that generates the logs; * work with a variety of the versions of the software that generates the logs;
* work with the range of logging configuration options available in the * work with the range of logging configuration options available in the
software; software;
* work in multiple operating systems; * work with multiple operating systems;
* not make assumptions about the log format in excess of the software; * not make assumptions about the log format in excess of the software (don't
* make assumptions as to how future versions of the software will log messages; assume a username doesn't contain spaces and use \S+ unless you've checked
* not be susceptible to DoS vulnerabilities; and the source code);
* make assumptions as to how future versions of the software will log messages
(guess what would happen to the log message if different authentication
types are added);
* not be susceptible to DoS vulnerabilities (see Filter Security below); and
* match intended log lines only. * match intended log lines only.
Please follow the steps from Filter Test Cases to Developing Filter Regular Please follow the steps from Filter Test Cases to Developing Filter Regular
@ -59,14 +63,14 @@ Purpose:
Start by finding the log messages that the application generates related to Start by finding the log messages that the application generates related to
some form of authentication failure. If you are adding to an existing filter some form of authentication failure. If you are adding to an existing filter
think about whether the log messages are of a similar importance and purpose think about whether the log messages are of a similar importance and purpose
to the existing filter. If you where a user of fail2ban, and did a package to the existing filter. If you are a user of fail2ban, and did a package
update of fail2ban that started matching the new log messages, would anything update of fail2ban that started matching the new log messages, would anything
unexpected happen? Would the bantime/findtime for the jail be appropriate for unexpected happen? Would the bantime/findtime for the jail be appropriate for
the new log messages. If it doesn't perhaps it needs to be in a separate the new log messages. If it doesn't perhaps it needs to be in a separate
filter definition, for example like exim is authentication failures and filter definition, for example like exim is authentication failures and
exim-spam contains log messages related to spam. exim-spam contains log messages related to spam.
Even if its a new filter you may consider separating the log messages into Even if it is a new filter you may consider separating the log messages into
different filters based on purpose. different filters based on purpose.
Cause: Cause:
@ -101,6 +105,12 @@ Log samples should include only one, definitely not more than 3, examples of
log messages of the same form. If log messages are different in different log messages of the same form. If log messages are different in different
versions of the application log messages that show this is encouraged. versions of the application log messages that show this is encouraged.
Also attempt inject an IP into the application so that fail2ban detects the IP
from user input rather than the true origin. See the Filter Security section
and the top example in testcases/files/logs/apache-auth as to how to do this.
One you have discovered this correct the regex so it doesn't match and provide
this as a test case with match: false (see failJSON below).
If the mechanism to create the log message isn't obvious provide a If the mechanism to create the log message isn't obvious provide a
configuration and/or sample scripts testcases/files/config/{filtername} and configuration and/or sample scripts testcases/files/config/{filtername} and
reference these in the comments above the log line. reference these in the comments above the log line.