Significant bug fix to honor the full encryption key length for
user-supplied Rijndael keys > 16 bytes long. Previous to this bug fix,
only the first 16 bytes of a key were actually used in the encryption/
decryption process even if the supplied key was longer. The result was
a weakening of expected security for users that had keys > 16 bytes,
although this is probably not too common. Note that "passphrase" is
perhaps technically a better word for "user-supplied key" in this
context since Rijndael in CBC mode derives a real encryption/decryption
key from the passphrase through a series of applications of md5 against
the passphrase and a random salt. This issue was reported by Michael T.
Dean. Closes issue #18 on github.
[client] (Franck Joncourt) Contributed a patch to allow the fwknop
client to be stopped during the password entry prompt with Ctrl-C before
any SPA packet is sent on the wire.
[client+server] Applied patch from Franck Joncourt to remove unnecessary
chmod() call when creating client rc file and server replay cache file.
The permissions are now set appropriately via open(), and at the same
time this patch fixes a potential race condition since the previous code
used fopen() followed by chmod().
Applied patch from Franck Joncourt to have the perl FKO module link
against libfko in the local directory (if it exists) so that it doesn't
have to have libfko completely installed in /usr/lib/. This allows the
test suite to run FKO tests without installing libfko.
Added the ability to the test suite to compile, install, and run some
basic tests against the perl FKO module.
(Vlad Glagolev) Submitted a patch to fix command exec mode
under SPA message type validity test. Support for command exec mode was
also added to the test suite.
Applied patch from Vlad Glagolev to fix ndbm/gdbm usage when --disable-file-cache
is used for the autoconf configure script. This functionality was broken in
be4193d734850fe60f14a26b547525ea0b9ce1e9 through improper handling of #define
macros from --disable-file-cache.
Fernando Arnaboldi from IOActive found several conditions in
which the server did not properly throw out maliciously constructed
variables in the access.conf file. This has been fixed along with new
fuzzing tests in the test suite.
This commit fixes a condition in which the server did not properly validate
allow IP addresses from malicious authenticated clients. This has been fixed
with stronger allow IP validation.
- [server] Fernando Arnaboldi from IOActive found several DoS/code
execution vulnerabilities for malicious fwknop clients that manage to
get past the authentication stage (so a such a client must be in
possession of a valid access.conf encryption key). These vulnerbilities
manifested themselves in the handling of malformed access requests, and
both the fwknopd server code along with libfko now perform stronger input
validation of access request data. These vulnerabilities affect
pre-2.0.3 fwknop releases.
- [test suite] Added a new fuzzing capability to ensure proper server-side
input validation. Fuzzing data is constructed with modified fwknop
client code that is designed to emulate malicious behavior.
Implemented a new check to ensure that the iptables 'comment' match exists to
ensure the proper environment for fwknopd operations. This check is controlled
by the new ENABLE_IPT_COMMENT_CHECK variable, and was suggested by Hank
Leininger.
[server] Updated PCAP_LOOP_SLEEP default to 1/10th of a second (in
microseconds). This was supposed to be the default anyway, but C
Anthony Risinger reported a bug where fwknopd was consuming more
resources than necessary, and the cause was PCAP_LOOP_SLEEP set by
default to 1/100th of a second - this has been fixed.
This commit fixes a bug where the same encryption key used for two stanzas in
the access.conf file would result in access requests that matched the second
stanza to always be treated as a replay attack. This has been fixed for
the fwknop-2.0.1 release, and was reported by Andy Rowland. Now the fwknopd
server computes the SHA256 digest of raw incoming payload data before
decryption, and compares this against all previous hashes. Previous to this
commit, fwknopd would add a new hash to the replay digest list right after
the first access.conf stanza match, so when SPA packet data matched the
second access.conf stanza a matching replay digest would already be there.
