We don't need an IV for NULL encryption, so we wouldn't technically need
an IV generator. But some of the code currently relies on an IV
generator to be present. So we don't have to change that code and
handle IV size == 0 specially we use the new NULL IV generator, which
handles this transparently to the existing code.
Before 3c81cb6fc3 ("aead: Create AEAD using traditional transforms
with an explicit IV generator") iv_gen_rand_t was used for NULL
encryption, which would work too but this way it's clearer.
We use the message ID and fragment number as IV generator. As IKEv2 uses
distinct message ID counters for actively and passively initiated exchanges,
each IV would be used twice. As we explicitly reject such message IDs since
d0ed1079, original-responder initiated exchanges fail with counter mode ciphers.
This commit separates IV space in two halves for sequential IVs, and
automatically assigns once reused sequence numbers to the second half.
Fixes#980.
We previously didn't pass the key size during algorithm registration, but this
resulted in benchmarking with the "default" key size the crypter uses when
passing 0 as key size.
Real AEADs directly provide a suitable IV generator, but traditional crypters
do not. For some (stream) ciphers, we should use sequential IVs, for which
we pass an appropriate generator to the AEAD wrapper.
Before this fix it was possible to crash charon with an IKE_SA_INIT
message containing a KE payload with DH group MODP_CUSTOM(1025).
Defining MODP_CUSTOM outside of the two byte IKE DH identifier range
prevents it from getting negotiated.
Fixes CVE-2014-9221.
The OID (1.3.6.1.4.1.3029.1.2) is technically not correct, the correct
one is (1.3.6.1.4.1.3029.1.1.2). Every other library or tool (like OpenSSL)
uses the incorrect one so we do the same.
References #740.
While it was always documented as boolean setting, the option is currently
handled as integer value, for which yes/no values do not work. Instead the
default of TRUE is used for a no value.
The option has been moved a lot during the last years, and in some locations
was handled as bool, in some as integer. In the latest codebase it
congruently used integer, which is actually not what is documented and used
in testing.
Fixes#781.
The new get_byte() method returns a pseudo-random byte at a time.
Changed the get_bits() interface to the same interface as get_byte().
Updated the mgf1 unit-tests accordingly.
Andreas Steffen