This is the first of two commits; bringing in the kernel support first.
This can be enabled by compiling a kernel with options TCP_SIGNATURE
and FAST_IPSEC.
For the uninitiated, this is a TCP option which provides for a means of
authenticating TCP sessions which came into being before IPSEC. It is
still relevant today, however, as it is used by many commercial router
vendors, particularly with BGP, and as such has become a requirement for
interconnect at many major Internet points of presence.
Several parts of the TCP and IP headers, including the segment payload,
are digested with MD5, including a shared secret. The PF_KEY interface
is used to manage the secrets using security associations in the SADB.
There is a limitation here in that as there is no way to map a TCP flow
per-port back to an SPI without polluting tcpcb or using the SPD; the
code to do the latter is unstable at this time. Therefore this code only
supports per-host keying granularity.
Whilst FAST_IPSEC is mutually exclusive with KAME IPSEC (and thus IPv6),
TCP_SIGNATURE applies only to IPv4. For the vast majority of prospective
users of this feature, this will not pose any problem.
This implementation is output-only; that is, the option is honoured when
responding to a host initiating a TCP session, but no effort is made
[yet] to authenticate inbound traffic. This is, however, sufficient to
interwork with Cisco equipment.
Tested with a Cisco 2501 running IOS 12.0(27), and Quagga 0.96.4 with
local patches. Patches for tcpdump to validate TCP-MD5 sessions are also
available from me upon request.
Sponsored by: sentex.net
change 38496
o add ipsec_osdep.h that holds os-specific definitions for portability
o s/KASSERT/IPSEC_ASSERT/ for portability
o s/SPLASSERT/IPSEC_SPLASSERT/ for portability
o remove function names from ASSERT strings since line#+file pinpints
the location
o use __func__ uniformly to reduce string storage
o convert some random #ifdef DIAGNOSTIC code to assertions
o remove some debuggging assertions no longer needed
change 38498
o replace numerous bogus panic's with equally bogus assertions
that at least go away on a production system
change 38502 + 38530
o change explicit mtx operations to #defines to simplify
future changes to a different lock type
change 38531
o hookup ipv4 ctlinput paths to a noop routine; we should be
handling path mtu changes at least
o correct potential null pointer deref in ipsec4_common_input_cb
chnage 38685
o fix locking for bundled SA's and for when key exchange is required
change 38770
o eliminate recursion on the SAHTREE lock
change 38804
o cleanup some types: long -> time_t
o remove refrence to dead #define
change 38805
o correct some types: long -> time_t
o add scan generation # to secpolicy to deal with locking issues
change 38806
o use LIST_FOREACH_SAFE instead of handrolled code
o change key_flush_spd to drop the sptree lock before purging
an entry to avoid lock recursion and to avoid holding the lock
over a long-running operation
o misc cleanups of tangled and twisty code
There is still much to do here but for now things look to be
working again.
Supported by: FreeBSD Foundation
o add locking
o strip irrelevant spl's
o split malloc types to better account for memory use
o remove unused IPSEC_NONBLOCK_ACQUIRE code
o remove dead code
Sponsored by: FreeBSD Foundation
o fix #ifdef typo
o must use "bounce functions" when dispatched from the protosw table
don't know how this stuff was missed in my testing; must've committed
the wrong bits
Pointy hat: sam
Submitted by: "Doug Ambrisko" <ambrisko@verniernetworks.com>
from the KAME IPsec implementation, but with heavy borrowing and influence
of openbsd. A key feature of this implementation is that it uses the kernel
crypto framework to do all crypto work so when h/w crypto support is present
IPsec operation is automatically accelerated. Otherwise the protocol
implementations are rather differet while the SADB and policy management
code is very similar to KAME (for the moment).
Note that this implementation is enabled with a FAST_IPSEC option. With this
you get all protocols; i.e. there is no FAST_IPSEC_ESP option.
FAST_IPSEC and IPSEC are mutually exclusive; you cannot build both into a
single system.
This software is well tested with IPv4 but should be considered very
experimental (i.e. do not deploy in production environments). This software
does NOT currently support IPv6. In fact do not configure FAST_IPSEC and
INET6 in the same system.
Obtained from: KAME + openbsd
Supported by: Vernier Networks