new ssh rule(s) added:
- Connection reset by peer (multi-line rule during authorization process);
- No supported authentication methods available;
Single line and multi-line expression optimized, added optional prefixes and suffix (logged from several ssh versions);
closes gh-864
SmartOS (and likely other Illumos platforms) enter log entries for failed sshd logins of the form:
`Authentication failed for USER from HOST`
The current sshd.conf regex matches `failure` -- add to this a match for `failed` to support Illumos
The regex for matching against "Auth fail" disconnect log message does
not match against current versions of ssh. OpenSSH 5.9 introduced
privilege separation of the pre-auth process, which included
[logging through monitor.c](http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/monitor.c.diff?r1=1.113&r2=1.114)
which adds " [preauth]" to the end of each message and causes the log
level to be prepended to each message.
It also fails to match against clients which send a disconnect message
with a description that is either empty or includes a space, since this
is the content in the log message after the disconnect code, per
[packet.c:1785](http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/packet.c?annotate=1.215),
which was matched by \S+. Although I have not observed this yet, I
couldn't find anything which would preclude it in [RFC
4253](https://tools.ietf.org/html/rfc4253#section-11.1) and since the
message is attacker-controlled it provides a way to avoid getting
banned.
This commit fixes both issues.
Signed-off-by: Kevin Locke <kevin@kevinlocke.name>
since daemon might eventually change reported length and we would need to adjust anyways. So limiting
in length does not provide additional security but allows for a possible injection vector
Origin: from https://github.com/jamesstout/fail2ban
* 'OpenSolaris' of https://github.com/jamesstout/fail2ban:
ENH: Removed unused log line
BF: fail2ban.local needs section headers
ENH: Use .local config files for logtarget and jail
ENH+TST: ssh failure messages for OpenSolaris and OS X
ENH: fail message matching for OpenSolaris and OS X
ENH: extra daemon info regex
ENH: actionunban back to a sed command
Readme for config on Solaris
create socket/pid dir if needed
Extra patterns for Solaris
change sed to perl for Solaris
Conflicts:
config/filter.d/sshd.conf
- OpenSolaris keyboard message matched by new regex 3
- Removed Bye Bye regex per
https://github.com/fail2ban/fail2ban/issues/175#issuecomment-16538036
- PAM auth failure or error and first char case-insensitive, can also
have chars after the hostname. e.g.
Apr 29 16:53:38 Jamess-iMac.local sshd[47831]: error: PAM:
authentication error for james from 205.186.180.101 via 192.168.1.201
Do not trigger sshd bans on pam_unix authentication failures, this will trigger on successful logins on systems that use non-pam_unix authentication (sssd, ldap, etc.).
sebres