isr is a shared resource and using isr->sav as a temporal storage
for each packet processing is racy. And also having a reference from
isr to sav makes the lifetime of sav non-deterministic; such a reference
is removed when a packet is processed and isr->sav is overwritten by
new one. Let's have a sav locally for each packet processing instead of
using shared isr->sav.
However this change doesn't stop using isr->sav yet because there are
some users of isr->sav. isr->sav will be removed after the users find
a way to not use isr->sav.
It seems that PACKET_TAG_IPSEC_IN_CRYPTO_DONE is for network adapters
that have IPsec accelerators; a driver sets the mtag to a packet
when its device has already encrypted the packet.
Unfortunately no driver implements such offload features for long
years and seems unlikely to implement them soon. (Note that neither
FreeBSD nor Linux doesn't have such drivers.) Let's remove related
(unused) codes and simplify the IPsec code.
-RFC2104 says that the block size of the hash algorithm must be used
for key/ipad/opad calculations. While formerly all ciphers used a block
length of 64, SHA384 and SHA512 use 128 bytes. So we can't use the
HMAC_BLOCK_LEN constant anymore. Add a new field to "struct auth_hash"
for the per-cipher blocksize.
-Due to this, there can't be a single "CRYPTO_SHA2_HMAC" external name
anymore. Replace this by 3 for the 3 different keysizes.
This was done by Open/FreeBSD before.
-Also fix the number of authenticator bits used tor ESP and AH to
conform to RFC4868, and remove uses of AH_HMAC_HASHLEN which did
assume a fixed authenticator size of 12 bytes.
FAST_IPSEC will not interoperate with KAME IPSEC anymore if sha2 is used,
because the latter doesn't implement these standards. It should
interoperate with at least modern Free/OpenBSD now.
(I've only tested with NetBSD-current/FAST_IPSEC on both ends.)
Fast-IPsec is a rework of the OpenBSD and KAME IPsec code, using the
OpenCryptoFramework (and thus hardware crypto accelerators) and
numerous detailed performance improvements.
This import is (aside from SPL-level names) the FreeBSD source,
imported ``as-is'' as a historical snapshot, for future maintenance
and comparison against the FreeBSD source. For now, several minor
kernel-API differences are hidden by macros a shim file, ipsec_osdep.h,
which (aside from SPL names) can be targeted at either NetBSD or FreeBSD.
