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.
This is a significant commit to add the ability to leverage libfko fault
injections from both the fwknop client and server command lines via a
new option '--fault-injection-tag <tag name>'. This option is used by
the test suite with the tests/fault_injection.pl tests.
- [server] When GnuPG is used, the default now is to require that
incoming SPA packets are signed by a key listed in GPG_REMOTE_ID for each
access.conf stanza. In other words, the usage of GPG_REQUIRE_SIG
is no longer necessary in order to authenticate SPA packets via the
GnuPG signature. Verification of GnuPG signatures can be disabled with a
new access.conf variable GPG_DISABLE_SIG, but this is NOT a
recommended configuration.
- [client+server] Add --gpg-exe command line argument and GPG_EXE
config variable to ~/.fwknoprc and the access.conf file so that the path
to GnuPG can be changed from the default /usr/bin/gpg path.
Suggested doc update to fwknop man pages to accurately describe the usage
of digits instead of bytes for SPA random data. About 53 bits of entropy
are actually used, although this is in addition to the 64-bit random salt
in for key derivation used by PBKDF1 in Rjindael CBC mode.
This commit bumps the fwknop version to 2.5 and sets the libfko version to 2.0 to
signal incompatibility with older libfko versions. Backwards compatibility is
maintained in SPA packet construction, but function prototypes in libfko-2.0 are
no longer compatible with older versions.
This commit also returns non-zero exit status under 'fwknopd --status' if there
is no existing fwknopd process. This is better than always exiting with a zero
status regardless of whether fwknopd is already running or not, and adds a level
of scriptability to --status usage. This change was suggested by George Herlin.
This change brings similar functionality to the client as the GPG_ALLOW_NO_PW
keyword in the server access.conf file. Although this option is less likely
to be used than the analogous server functionality, it stands to reason that
the client should offer this feature. The test suite has also been updated to
not use the --get-key option for the 'no password' GPG tests.
This change simplifies the fwknop client usage by allowing the -D argument to
be used as the stanza name if -n is not also specified in --save-rc-stanza
mode.
- [client] Added '-P udpraw' to allow the client to send SPA packets over
UDP with a spoofed source IP address. This is in addition to the
original 'tcpraw' and 'icmp' protocols that also support a spoofed
source IP.
- [server] Bug fix to accept SPA packets over ICMP if the fwknop client
is executed with '-P icmp' and the user has the required privileges.
This is a significant update to allow AES encryption modes to be selected on a
per-key basis. For now, only ECB and CBC (recommended) modes are supported.
The default is ECB modes in order to maintain backwards compatibility with the
older perl version of fwknop and the Crypt::CBC CPAN module. This will likely
be changed to use CBC mode by default because of its better security
properties.
In the access.conf file on the server side, there is a new configuration
variable "ENCRYPTION_MODE" that controls the mode for the corresponding AES
key. On the client side, a new command line argument "--encryption-mode"
controls how the client encrypts SPA packets.
This commit adds a new configuration variable "FORCE_NAT" to the access.conf
file:
For any valid SPA packet, force the requested connection to be NAT'd
through to the specified (usually internal) IP and port value. This is
useful if there are multiple internal systems running a service such as
SSHD, and you want to give transparent access to only one internal system
for each stanza in the access.conf file. This way, multiple external
users can each directly access only one internal system per SPA key.
This commit also implements a few minor code cleanups.
