How to log every login (SSH) on FreeBSD

Question

I want to log every SSH login attempts, both successful and not, to my FreeBSD server to a file, and daily mail this log to root.

I could accomplish something like this by parsing /var/log/auth.log, but a) this contains more than login attempts, and b) it could be turned over since yesterday's run. Is there a more direct way of doing this; for instance a hook in SSHd or login configuration to log each login?

Solution 1

The default is to log to the AUTH facility. You can change the facility that sshd logs to with the SyslogFacility configuration option.

SyslogFacility LOCAL7

Then configure your syslogd to write local7.* to it's own file by adding

local7.*     /var/log/local7.log

to the syslogd configuration file. Tell syslogd to reread it's config file by sending it a HUP signal do the same for sshd and you should have sshd messages being sent to it's own file.

Solution 2

I stumbled upon this blog-post that describes multiple solutions to my question. Among other things it mentions log-parsing and, interestingly, PAM scripting through pam_exec. This enables me to run my own script on every login.

I think this is the most flexible solution to my problem, although Iain's previous answer probably is less invasive and also solves my problem.

Comments

[poplitea]

Thank you! :-) This is one possible solution. I also found another; PAM scripting -- see my own answer.