"ipid" options. This feature has been requested by several users.
On passing, fix some minor bugs in the parser. This change is fully
backward compatible so if you have an old /sbin/ipfw and a new
kernel you are not in trouble (but you need to update /sbin/ipfw
if you want to use the new features).
Document the changes in the manpage.
Now you can write things like
ipfw add skipto 1000 iplen 0-500
which some people were asking to give preferential treatment to
short packets.
The 'MFC after' is just set as a reminder, because I still need
to merge the Alpha/Sparc64 fixes for ipfw2 (which unfortunately
change the size of certain kernel structures; not that it matters
a lot since ipfw2 is entirely optional and not the default...)
PR: bin/48015
MFC after: 1 week
this makes connect act more sensibly in these cases.
PR: 50839
Submitted by: Barney Wolff <barney@pit.databus.com>
Patch delayed by laziness of: silby
MFC after: 1 week
is not called, and no static rules match an outgoing packet, the
latter retains its source IP address. This is in support of the
"static NAT only" mode.
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
sure that the MAC label on TCP responses during TIMEWAIT is
properly set from either the socket (if available), or the mbuf
that it's responding to.
Unfortunately, this is made somewhat difficult by the TCP code,
as tcp_twstart() calls tcp_twrespond() after discarding the socket
but without a reference to the mbuf that causes the "response".
Passing both the socket and the mbuf works arounds this--eventually
it might be good to make sure the mbuf always gets passed in in
"response" scenarios but working through this provided to
complicate things too much.
Approved by: re (scottl)
Reviewed by: hsu
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
copying for mbuf headers now works properly in m_dup_pkthdr(), so
we don't need to do an explicit copy.
Approved by: re (jhb)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
state. Those changed attempted to work around the changed invariant
that inp->in_socket was sometimes now NULL, but the logic wasn't
quite right, meaning that inp->in_socket would be dereferenced by
cr_canseesocket() if security.bsd.see_other_uids, jail, or MAC
were in use. Attempt to clarify and correct the logic.
Note: the work-around originally introduced with the reduced TCP
wait state handling to use cr_cansee() instead of cr_canseesocket()
in this case isn't really right, although it "Does the right thing"
for most of the cases in the base system. We'll need to address
this at some point in the future.
Pointed out by: dcs
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
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>
doing Limited Transmit. Only artificially inflate the congestion
window by 1 segment instead of the usual 3 to take into account
the 2 already sent by Limited Transmit.
Approved in principle by: Mark Allman <mallman@grc.nasa.gov>,
Hari Balakrishnan <hari@nms.lcs.mit.edu>, Sally Floyd <floyd@icir.org>
(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.
Quote from kern/37573:
There is an obvious race in netinet/ip_dummynet.c:config_pipe().
Interrupts are not blocked when changing the params of an
existing pipe. The specific crash observed:
... -> config_pipe -> set_fs_parms -> config_red
malloc a new w_q_lookup table but take an interrupt before
intializing it, interrupt handler does:
... -> dummynet_io -> red_drops
red_drops dereferences the uninitialized (zeroed) w_q_lookup
table.
o Flush accumulated credits for idle pipes.
o Flush accumulated credits when change pipe characteristics.
o Change dn_flow_queue.numbytes type to unsigned long.
Overlapping dn_flow_queue->numbytes in ready_event() leads to
numbytes becomes negative and SET_TICKS() macro returns a very
big value. heap_insert() overlaps dn_key again and inserts a
queue to a ready heap with a sched_time points to the past.
That leads to an "infinity" loop.
PR: kern/33234, kern/37573, misc/42459, kern/43133,
kern/44045, kern/48099
Submitted by: Mike Hibler <mike@cs.utah.edu> (kern/37573)
MFC after: 6 weeks
additional flags argument to indicate blocking disposition, and
pass in M_NOWAIT from the IP reassembly code to indicate that
blocking is not OK when labeling a new IP fragment reassembly
queue. This should eliminate some of the WITNESS warnings that
have started popping up since fine-grained IP stack locking
started going in; if memory allocation fails, the creation of
the fragment queue will be aborted.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
- 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. :)
comes in on is the same interface that we would route out of to get to
the packet's source address. Essentially automates an anti-spoofing
check using the information in the routing table.
Experimental. The usage and rule format for the feature may still be
subject to change.
drain routines are done by swi_net, which allows for better queue control
at some future point. Packets may also be directly dispatched to a netisr
instead of queued, this may be of interest at some installations, but
currently defaults to off.
Reviewed by: hsu, silby, jayanth, sam
Sponsored by: DARPA, NAI Labs
that matches snd_max, then do not respond with an ack, just drop the
segment. This fixes a problem where a simultaneous close results in
an ack loop between two time-wait states.
Test case supplied by: Tim Robbins <tjr@FreeBSD.ORG>
Sponsored by: DARPA, NAI Labs
tcpcb is NULL, but also its connected inpcb, since we now allow
elements of a TCP connection to hang around after other state, such
as the socket, has been recycled.
Tested by: dcs
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Security improvements:
- Increase the size of each syncookie secret from 32 to 128 bits
in order to make brute force attacks on the secrets much more
difficult.
- Always return the lowest order dword from the MD5 hash; this
allows us to expose 2 more bits of the cookie and makes ACK
floods which seek to guess the cookie value more difficult.
Performance improvements:
- Increase the lifetime of each syncookie from 4 seconds to 16
seconds. This increases the usefulness of syncookies during
an attack.
- From Yahoo!: Reduce the number of calls to MD5Update; this
results in a ~17% increase in cookie generation time here.
Reviewed by: hsu, jayanth, jlemon, nectar
MFC After: 15 seconds
packets coming out of a GIF tunnel are re-processed by ipfw, et. al.
By default they are not reprocessed. With the option they are.
This reverts 1.214. Prior to that change packets were not re-processed.
After they were which caused problems because packets do not have
distinguishing characteristics (like a special network if) that allows
them to be filtered specially.
This is really a stopgap measure designed for immediate MFC so that
4.8 has consistent handling to what was in 4.7.
PR: 48159
Reviewed by: Guido van Rooij <guido@gvr.org>
MFC after: 1 day
and enable it by default, with a limit of 16.
At the same time, tweak maxfragpackets downward so that in the worst
possible case, IP reassembly can use only 1/2 of all mbuf clusters.
MFC after: 3 days
Reviewed by: hsu
Liked by: bmah
OSes has probably caused more problems than it ever solved. Allow the
user to retire the old behavior by specifying their own privileged
range with,
net.inet.ip.portrange.reservedhigh default = IPPORT_RESERVED - 1
net.inet.ip.portrange.reservedlo default = 0
Now you can run that webserver without ever needing root at all. Or
just imagine, an ftpd that can really drop privileges, rather than
just set the euid, and still do PORT data transfers from 20/tcp.
Two edge cases to note,
# sysctl net.inet.ip.portrange.reservedhigh=0
Opens all ports to everyone, and,
# sysctl net.inet.ip.portrange.reservedhigh=65535
Locks all network activity to root only (which could actually have
been achieved before with ipfw(8), but is somewhat more
complicated).
For those who stick to the old religion that 0-1023 belong to root and
root alone, don't touch the knobs (or even lock them by raising
securelevel(8)), and nothing changes.
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
routine does not require a tcpcb to operate. Since we no longer keep
template mbufs around, move pseudo checksum out of this routine, and
merge it with the length update.
Sponsored by: DARPA, NAI Labs
- delay acks for T/TCP regardless of delack setting
- fix bug where a single pass through tcp_input might not delay acks
- use callout_active() instead of callout_pending()
Sponsored by: DARPA, NAI Labs
cr_uid.
Note: we do not have socheckuid() in RELENG_4, ip_fw2.c uses its
own macro for a similar purpose that is why ipfw2 in RELENG_4 processes
uid rules correctly. I will MFC the diff for code consistency.
Reported by: Oleg Baranov <ol@csa.ru>
Reviewed by: luigi
MFC after: 1 month
ipsec4_process_packet; they happen when a packet is dropped because
an SA acquire is initiated
Submitted by: Doug Ambrisko <ambrisko@verniernetworks.com>
you still don't want to use the two together, but it's ok to have
them in the same kernel (the problem that initiated this bandaid
has long since been fixed)
initialized until after a syncookie was generated. As a result,
all connections resulting from a returned cookie would end up using
a MSS of ~512 bytes. Now larger packets will be used where possible.
MFC after: 5 days
- Honor the previous behavior of maxfragpackets = 0 or -1
- Take a better stab at fragment statistics
- Move / correct a comment
Suggested by: maxim@
MFC after: 7 days
functions implemented approximately the same limits on fragment memory
usage, but in different fashions.)
End user visible changes:
- Fragment reassembly queues are freed in a FIFO manner when maxfragpackets
has been reached, rather than all reassembly stopping.
MFC after: 5 days