Bug fix for a crash in libfko that could be triggered in fko_set_username()
when a username that is 64 chars or longer is specified. This crash
cannot be triggered in fwknopd even if an SPA packet contains such a
username however due to additional protections in the SPA decoding
routines. Further, this bug does not apply to the main fwknop client
either because the maximal username size is truncated down below 64
bytes. Hence, this bug only applies to client-side software that is
directly using libfko calling the fko_set_username() function.
By default, fwknopd will now exit if the interface that it is
sniffing goes down (patch contributed by Github user 'sgh7'). If this
happens, it is expected that the native process monitoring feature in
things like systemd or upstart will restart fwknopd. However, if fwknopd
is not being monitored by systemd, upstart, or anything else, this
behavior can be disabled with the EXIT_AT_INTF_DOWN variable in the
fwknopd.conf file. If disabled, fwknopd will try to recover when a
downed interface comes back up.
Bug fix to ensure that a User-Agent string can be specified when the
fwknop client uses wget via SSL to resolve the external IP address. This
closes issue #134 on github reported by Barry Allard. The fwknop now
uses the wget '-U' option to specify the User-Agent string with a
default of "Fwknop/<version>". In addition, a new command line argument
"--use-wget-user-agent" to allow the default wget User-Agent string to
apply instead.
External IP resolution via '-R' (or '--resolve-ip-http') is now done via SSL by
default. The IP resolution URL is now 'https://www.cipherdyne.org/cgi-gin/myip',
and a warning is generated in '-R' mode whenever a non-HTTPS URL is specified
(it is safer just to use the default). The fwknop client leverages 'wget' for
this operation since that is cleaner than having fwknop link against an SSL
library.
