have already done this, so I have styled the patch on their work:
1) introduce a ip_newid() static inline function that checks
the sysctl and then decides if it should return a sequential
or random IP ID.
2) named the sysctl net.inet.ip.random_id
3) IPv6 flow IDs and fragment IDs are now always random.
Flow IDs and frag IDs are significantly less common in the
IPv6 world (ie. rarely generated per-packet), so there should
be smaller performance concerns.
The sysctl defaults to 0 (sequential IP IDs).
Reviewed by: andre, silby, mlaier, ume
Based on: NetBSD
MFC after: 2 months
your (network) modules as well as any userland that might make sense of
sizeof(struct ifnet).
This does not change the queueing yet. These changes will follow in a
seperate commit. Same with the driver changes, which need case by case
evaluation.
__FreeBSD_version bump will follow.
Tested-by: (i386)LINT
in favour of rtalloc_ign(), which is what would end up being called
anyways.
There are 25 more instances of rtalloc() in net*/ and
about 10 instances of rtalloc_ign()
we convert ip_len into a network byte order; in_delayed_cksum() still
expects it in host byte order.
The symtom was the ``in_cksum_skip: out of data by %d'' complaints
from the kernel.
To add to the previous commit log. These fixes make tcpdump(1) happy
by not complaining about UDP/TCP checksum being bad for looped back
IP multicast when multicast router is deactivated.
Reported by: Vsevolod Lobko
Compute the payload checksum for a locally originated IP multicast where
God intended, in ip_mloopback(), rather than doing it in ip_output() and
only when multicast router is active. This is more correct as we do not
fool ip_input() that the packet has the correct payload checksum when in
fact it does not (when multicast router is inactive). This is also more
efficient if we don't join the multicast group we send to, thus allowing
the hardware to checksum the payload.
ifp is now passed explicitly to ether_demux; no need to look it up again.
Make mtag a global var in ip_input.
Noticed by: rwatson
Approved by: bms(mentor)
them mostly with packet tags (one case is handled by using an mbuf flag
since the linkage between "caller" and "callee" is direct and there's no
need to incur the overhead of a packet tag).
This is (mostly) work from: sam
Silence from: -arch
Approved by: bms(mentor), sam, rwatson
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
restore the general pre-randomid behaviour.
Setting the ip_id to zero causes several problems with
packet reassembly when a device along the path removes
the DF bit for some reason.
Other BSD and Linux have found and fixed the same issues.
PR: kern/60889
Tested by: Richard Wendland <richard@wendland.org.uk>
Approved by: re (scottl)
the routing table. Move all usage and references in the tcp stack
from the routing table metrics to the tcp hostcache.
It caches measured parameters of past tcp sessions to provide better
initial start values for following connections from or to the same
source or destination. Depending on the network parameters to/from
the remote host this can lead to significant speedups for new tcp
connections after the first one because they inherit and shortcut
the learning curve.
tcp_hostcache is designed for multiple concurrent access in SMP
environments with high contention and is hash indexed by remote
ip address.
It removes significant locking requirements from the tcp stack with
regard to the routing table.
Reviewed by: sam (mentor), bms
Reviewed by: -net, -current, core@kame.net (IPv6 parts)
Approved by: re (scottl)
accordingly. The define is left intact for ABI compatibility
with userland.
This is a pre-step for the introduction of tcp_hostcache. The
network stack remains fully useable with this change.
Reviewed by: sam (mentor), bms
Reviewed by: -net, -current, core@kame.net (IPv6 parts)
Approved by: re (scottl)
complex locking and rework ip_rtaddr() to do its own rtlookup.
Adopt all its callers to this and make ip_output() callable
with NULL rt pointer.
Reviewed by: sam (mentor)
Short description of ip_fastforward:
o adds full direct process-to-completion IPv4 forwarding code
o handles ip fragmentation incl. hw support (ip_flow did not)
o sends icmp needfrag to source if DF is set (ip_flow did not)
o supports ipfw and ipfilter (ip_flow did not)
o supports divert, ipfw fwd and ipfilter nat (ip_flow did not)
o returns anything it can't handle back to normal ip_input
Enable with sysctl -w net.inet.ip.fastforwarding=1
Reviewed by: sam (mentor)
- share policy-on-socket for listening socket.
- don't copy policy-on-socket at all. secpolicy no longer contain
spidx, which saves a lot of memory.
- deep-copy pcb policy if it is an ipsec policy. assign ID field to
all SPD entries. make it possible for racoon to grab SPD entry on
pcb.
- fixed the order of searching SA table for packets.
- fixed to get a security association header. a mode is always needed
to compare them.
- fixed that the incorrect time was set to
sadb_comb_{hard|soft}_usetime.
- disallow port spec for tunnel mode policy (as we don't reassemble).
- an user can define a policy-id.
- clear enc/auth key before freeing.
- fixed that the kernel crashed when key_spdacquire() was called
because key_spdacquire() had been implemented imcopletely.
- preparation for 64bit sequence number.
- maintain ordered list of SA, based on SA id.
- cleanup secasvar management; refcnt is key.c responsibility;
alloc/free is keydb.c responsibility.
- cleanup, avoid double-loop.
- use hash for spi-based lookup.
- mark persistent SP "persistent".
XXX in theory refcnt should do the right thing, however, we have
"spdflush" which would touch all SPs. another solution would be to
de-register persistent SPs from sptree.
- u_short -> u_int16_t
- reduce kernel stack usage by auto variable secasindex.
- clarify function name confusion. ipsec_*_policy ->
ipsec_*_pcbpolicy.
- avoid variable name confusion.
(struct inpcbpolicy *)pcb_sp, spp (struct secpolicy **), sp (struct
secpolicy *)
- count number of ipsec encapsulations on ipsec4_output, so that we
can tell ip_output() how to handle the packet further.
- When the value of the ul_proto is ICMP or ICMPV6, the port field in
"src" of the spidx specifies ICMP type, and the port field in "dst"
of the spidx specifies ICMP code.
- avoid from applying IPsec transport mode to the packets when the
kernel forwards the packets.
Tested by: nork
Obtained from: KAME
that covers updates to the contents. Note this is separate from holding
a reference and/or locking the routing table itself.
Other/related changes:
o rtredirect loses the final parameter by which an rtentry reference
may be returned; this was never used and added unwarranted complexity
for locking.
o minor style cleanups to routing code (e.g. ansi-fy function decls)
o remove the logic to bump the refcnt on the parent of cloned routes,
we assume the parent will remain as long as the clone; doing this avoids
a circularity in locking during delete
o convert some timeouts to MPSAFE callouts
Notes:
1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level
applications cannot/do-no know about mutex's. Doing this requires
that the mutex be the last element in the structure. A better solution
is to introduce an externalized version of struct rtentry but this is
a major task because of the intertwining of rtentry and other data
structures that are visible to user applications.
2. There are known LOR's that are expected to go away with forthcoming
work to eliminate many held references. If not these will be resolved
prior to release.
3. ATM changes are untested.
Sponsored by: FreeBSD Foundation
Obtained from: BSD/OS (partly)
o revamp IPv4+IPv6+bridge usage to match API changes
o remove pfil_head instances from protosw entries (no longer used)
o add locking
o bump FreeBSD version for 3rd party modules
Heavy lifting by: "Max Laier" <max@love2party.net>
Supported by: FreeBSD Foundation
Obtained from: NetBSD (bits of pfil.h and pfil.c)
Changes from the original implementation:
- Fragmentation is handled by the function m_fragment, which can
be called from whereever fragmentation is needed. Note that this
function is wrapped in #ifdef MBUF_STRESS_TEST to discourage non-testing
use.
- m_fragment works slightly differently from the old fragmentation
code in that it allocates a seperate mbuf cluster for each fragment.
This defeats dma_map_load_mbuf/buffer's feature of coalescing adjacent
fragments. While that is a nice feature in practice, it nerfed the
usefulness of mbuf_stress_test.
- Add two modes of random fragmentation. Chains with fragments all of
the same random length and chains with fragments that are each uniquely
random in length may now be requested.
specific interfaces. This is required by aodvd, and may in future help us
in getting rid of the requirement for BPF from our import of isc-dhcp.
Suggested by: fenestro
Obtained from: BSD/OS
Reviewed by: mini, sam
Approved by: jake (mentor)
Disabled by default. To enable it, the new "options PIM" must be
added to the kernel configuration file (in addition to MROUTING):
options MROUTING # Multicast routing
options PIM # Protocol Independent Multicast
2. Add support for advanced multicast API setup/configuration and
extensibility.
3. Add support for kernel-level PIM Register encapsulation.
Disabled by default. Can be enabled by the advanced multicast API.
4. Implement a mechanism for "multicast bandwidth monitoring and upcalls".
Submitted by: Pavlin Radoslavov <pavlin@icir.org>
only meaningful for fragments. Also don't bother to byte-swap the
ip_id when we do generate it; it is only used at the receiver as a
nonce. I tried several different permutations of this code with no
measurable difference to each other or to the unmodified version, so
I've settled on the one for which gcc seems to generate the best code.
(If anyone cares to microoptimize this differently for an architecture
where it actually matters, feel free.)
Suggested by: Steve Bellovin's paper in IMW'02
of asserting that an mbuf has a packet header. Use it instead of hand-
rolled versions wherever applicable.
Submitted by: Hiten Pandya <hiten@unixdaemons.com>
(See: ftp://ftp.rfc-editor.org/in-notes/rfc3514.txt)
This fulfills the host requirements for userland support by
way of the setsockopt() IP_EVIL_INTENT message.
There are three sysctl tunables provided to govern system behavior.
net.inet.ip.rfc3514:
Enables support for rfc3514. As this is an
Informational RFC and support is not yet widespread
this option is disabled by default.
net.inet.ip.hear_no_evil
If set the host will discard all received evil packets.
net.inet.ip.speak_no_evil
If set the host will discard all transmitted evil packets.
The IP statistics counter 'ips_evil' (available via 'netstat') provides
information on the number of 'evil' packets recieved.
For reference, the '-E' option to 'ping' has been provided to demonstrate
and test the implementation.
- Don't try to fragment the packet if it's smaller than mbuf_frag_size.
- Preserve the size of the mbuf chain which is modified by m_split().
- Check that m_split() didn't return NULL.
- Make it so we don't end up with two M_PKTHDR mbuf in the chain.
- Use m->m_pkthdr.len instead of m->m_len so that we fragment the whole
chain and not just the first mbuf.
- Fix a nearby style bug and rework the logic of the loops so that it's
more clear.
This is still not quite right, because we're clearly abusing m_split() to
do something it was not designed for, but at least it works now. We
should probably move this code into a m_fragment() function when it's
correct.
allows you to tell ip_output to fragment all outgoing packets
into mbuf fragments of size net.inet.ip.mbuf_frag_size bytes.
This is an excellent way to test if network drivers can properly
handle long mbuf chains being passed to them.
net.inet.ip.mbuf_frag_size defaults to 0 (no fragmentation)
so that you can at least boot before your network driver dies. :)
control block. Allow the socket and tcpcb structures to be freed
earlier than inpcb. Update code to understand an inp w/o a socket.
Reviewed by: hsu, silby, jayanth
Sponsored by: DARPA, NAI Labs
ipsec4_process_packet; they happen when a packet is dropped because
an SA acquire is initiated
Submitted by: Doug Ambrisko <ambrisko@verniernetworks.com>
