When this happens, we know for sure that the packet data was not
received by the peer. Therefore, back out any advancing of the
transmit sequence number so that we send the same data the next
time we transmit a packet, avoiding a guaranteed missed packet and
its resulting TCP transmit slowdown.
In most systems ip_output() probably never returns an error, and
so this problem is never seen. However, it is more likely to occur
with device drivers having short output queues (causing ENOBUFS to
be returned when they are full), not to mention low memory situations.
Moreover, because of this problem writers of slow devices were
required to make an unfortunate choice between (a) having a relatively
short output queue (with low latency but low TCP bandwidth because
of this problem) or (b) a long output queue (with high latency and
high TCP bandwidth). In my particular application (ISDN) it took
an output queue equal to ~5 seconds of transmission to avoid ENOBUFS.
A more reasonable output queue of 0.5 seconds resulted in only about
50% TCP throughput. With this patch full throughput was restored in
the latter case.
Reviewed by: freebsd-net
delete the cloned route that is associated with the connection.
This does not exhaust the routing table memory when the system
is under a SYN flood attack. The route entry is not deleted if there
is any prior information cached in it.
Reviewed by: Peter Wemm,asmodai
reply if the requesting machine isn't on the interface we believe
it should be. Prevents arp wars when you plug cables in the wrong
way around.
PR: 9848
Submitted by: Ian Dowse <iedowse@maths.tcd.ie>
Not objected to by: wollman
- Multiple PPTP clients behind NAT to the same or different servers.
- Single PPTP server behind NAT -- you just need to redirect TCP
port 1723 to a local machine. Multiple servers behind NAT is
possible but would require a simple API change.
- No API changes!
For more information on how this works see comments at the start of
the alias_pptp.c.
PacketAliasPptp() is no longer necessary and will be removed soon.
Submitted by: Erik Salander <erik@whistle.com>
Reviewed by: ru
Rewritten by: ru
Reviewed by: Erik Salander <erik@whistle.com>
accept filters are now loadable as well as able to be compiled into
the kernel.
two accept filters are provided, one that returns sockets when data
arrives the other when an http request is completed (doesn't work
with 0.9 requests)
Reviewed by: jmg
It does mean that it is now possible to run passive-mode FTP
server behind NAT.
- SECURITY: FTP aliasing engine now ensures that:
o the segment preceding a PORT/227 segment terminates with a \r\n;
o the IP address in the PORT/227 matches the source IP address of
the packet;
o the port number in the PORT command or 277 reply is greater than
or equal to 1024.
Submitted by: Erik Salander <erik@whistle.com>
Reviewed by: ru
It also squashes 99% of packet kiddie synflood orgies. For example, to
rate syn packets without MSS,
ipfw pipe 10 config 56Kbit/s queue 10Packets
ipfw add pipe 10 tcp from any to any in setup tcpoptions !mss
Submitted by: Richard A. Steenbergen <ras@e-gerbil.net>
a mbuf, it may return without setting any timers. If no more data is
scheduled to be transmitted (this was a FIN) the system will sit in
LAST_ACK state forever.
Thus, when mbuf allocation fails, set the retransmit timer if neither
the retransmit or persist timer is already pending.
Problem discovered by: Mike Silbersack (silby@silby.com)
Pushed for a fix by: Bosko Milekic <bmilekic@dsuper.net>
Reviewed by: jayanth
down as a result of a reset. Returning EINVAL in that case makes no
sense at all and just confuses people as to what happened. It could be
argued that we should save the original address somewhere so that
getsockname() etc can tell us what it used to be so we know where the
problem connection attempts are coming from.
integer expression. Otherwise the sizeof() call will force the expression
to be evaluated as unsigned, which is not the intended behavior.
Obtained from: NetBSD (in a different form)
code retransmitting data from the wrong offset.
As a footnote, the newreno code was partially derived from NetBSD
and Tom Henderson <tomh@cs.berkeley.edu>
of the individual drivers and into the common routine ether_input().
Also, remove the (incomplete) hack for matching ethernet headers
in the ip_fw code.
The good news: net result of 1016 lines removed, and this should make
bridging now work with *all* Ethernet drivers.
The bad news: it's nearly impossible to test every driver, especially
for bridging, and I was unable to get much testing help on the mailing
lists.
Reviewed by: freebsd-net
better recovery for multiple packet losses in a single window.
The algorithm can be toggled via the sysctl net.inet.tcp.newreno,
which defaults to "on".
Submitted by: Jayanth Vijayaraghavan <jayanth@yahoo-inc.com>
calling in_pcbbind so that in_pcbbind sees a valid address if no
address was specified (since divert sockets ignore them).
PR: 17552
Reviewed by: Brian
to PPTP) with more generic PacketAliasRedirectProto().
Major number is not bumped because it is believed that noone
has started using PacketAliasRedirectPptp() yet.
LSNAT links are first created by either PacketAliasRedirectPort() or
PacketAliasRedirectAddress() and then set up by one or more calls to
PacketAliasAddServer().
Without this fix, all IPv6 TCP RST packet has wrong cksum value,
so IPv6 connect() trial to 5.0 machine won't fail until tcp connect timeout,
when they should fail soon.
Thanks to haro@tk.kubota.co.jp (Munehiro Matsuda) for his much debugging
help and detailed info.
connections, after SYN packets were seen from both ends. Before this,
it would get applied right after the first SYN packet was seen (either
from client or server). With broken TCP connection attempts, when the
remote end does not respond with SYNACK nor with RST, this resulted in
having a useless (ie, no actual TCP connection associated with it) TCP
link with 86400 seconds TTL, wasting system memory. With high rate of
such broken connection attempts (for example, remote end simply blocks
these connection attempts with ipfw(8) without sending RST back), this
could result in a denial-of-service.
PR: bin/17963
but with `dst_port' work for outgoing packets.
This case was not handled properly when I first fixed this
in revision 1.17.
This change is also required for the upcoming improved PPTP
support patches -- that is how I found the problem.
Before this change:
# natd -v -a aliasIP \
-redirect_port tcp localIP:localPORT publicIP:publicPORT 0:remotePORT
Out [TCP] [TCP] localIP:localPORT -> remoteIP:remotePORT aliased to
[TCP] aliasIP:localPORT -> remoteIP:remotePORT
After this change:
# natd -v -a aliasIP \
-redirect_port tcp localIP:localPORT publicIP:publicPORT 0:remotePORT
Out [TCP] [TCP] localIP:localPORT -> remoteIP:remotePORT aliased to
[TCP] publicIP:publicPORT -> remoteIP:remotePORT
INADDR_NONE: Incoming packets go to the alias address (the default)
INADDR_ANY: Incoming packets are not NAT'd (direct access to the
internal network from outside)
anything else: Incoming packets go to the specified address
Change a few inaddr::s_addr == 0 to inaddr::s_addr == INADDR_ANY
while I'm there.
redirected and when no target address has been specified, NAT
the destination address to the alias address rather than
allowing people direct access to your internal network from
outside.
mbuf is marked for delayed checksums, then additionally mark the
packet as having it's checksums computed. This allows us to bypass
computing/checking the checksum entirely, which isn't really needeed
as the packet has never hit the wire.
Reviewed by: green
Reported in Usenet by: locke@mcs.net (Peter Johnson)
While i was at it, prepended a 0x to the %D output, to make it clear that
the printed value is in hex (i assume %D has been chosen over %#x to
obey network byte order).
improperly doing the equivalent of (m = (function() == NULL)) instead
of ((m = function()) == NULL).
This fixes a NULL pointer dereference panic with runt arp packets.
Remove a bogus (redundant, just weird, etc.) key_freeso(so).
There are no consumers of it now, nor does it seem there
ever will be.
in6?_pcb.c:
Add an if (inp->in6?p_sp != NULL) before the call to
ipsec[46]_delete_pcbpolicy(inp). In low-memory conditions
this can cause a crash because in6?_sp can be NULL...
from iso88025.h.
o Add minimal llc support to iso88025_input.
o Clean up most of the source routing code.
* Submitted by: Nikolai Saoukh <nms@otdel-1.org>
Now most big problem of IPv6 is getting IPv6 address
assignment.
6to4 solve the problem. 6to4 addr is defined like below,
2002: 4byte v4 addr : 2byte SLA ID : 8byte interface ID
The most important point of the address format is that an IPv4 addr
is embeded in it. So any user who has IPv4 addr can get IPv6 address
block with 2byte subnet space. Also, the IPv4 addr is used for
semi-automatic IPv6 over IPv4 tunneling.
With 6to4, getting IPv6 addr become dramatically easy.
The attached patch enable 6to4 extension, and confirmed to work,
between "Richard Seaman, Jr." <dick@tar.com> and me.
Approved by: jkh
Reviewed by: itojun
ARP packets. This can incorrectly reject complete frames since the frame
could be stored in more than one mbuf.
The following patches fix the length comparisson, and add several
diagnostic log messages to the interrupt handler for out-of-the-norm ARP
packets. This should make ARP problems easier to detect, diagnose and
fix.
Submitted by: C. Stephen Gunn <csg@waterspout.com>
Approved by: jkh
Reviewed by: rwatson
Without this, kernel will panic at getsockopt() of IPSEC_POLICY.
Also make compilable libipsec/test-policy.c which tries getsockopt() of
IPSEC_POLICY.
Approved by: jkh
Submitted by: sakane@kame.net
KAME put INET6 related stuff into sys/netinet6 dir, but IPv6
standard API(RFC2553) require following files to be under sys/netinet.
netinet/ip6.h
netinet/icmp6.h
Now those header files just include each following files.
netinet6/ip6.h
netinet6/icmp6.h
Also KAME has netinet6/in6.h for easy INET6 common defs
sharing between different BSDs, but RFC2553 requires only
netinet/in.h should be included from userland.
So netinet/in.h also includes netinet6/in6.h inside.
To keep apps portability, apps should not directly include
above files from netinet6 dir.
Ideally, all contents of,
netinet6/ip6.h
netinet6/icmp6.h
netinet6/in6.h
should be moved into
netinet/ip6.h
netinet/icmp6.h
netinet/in.h
but to avoid big changes in this stage, add some hack, that
-Put some special macro define into those files under neitnet
-Let files under netinet6 cause error if it is included
from some apps, and, if the specifal macro define is not
defined.
(which should have been defined if files under netinet is
included)
-And let them print an error message which tells the
correct name of the include file to be included.
Also fix apps which includes invalid header files.
Approved by: jkh
Obtained from: KAME project
at the same time.
When rfc1323 and rfc1644 option are enabled by sysctl,
and tcp over IPv6 is tried, kernel panic happens by the
following check in tcp_output(), because now hdrlen is bigger
in such case than before.
/*#ifdef DIAGNOSTIC*/
if (max_linkhdr + hdrlen > MHLEN)
panic("tcphdr too big");
/*#endif*/
So change the above check to compare with MCLBYTES in #ifdef INET6 case.
Also, allocate a mbuf cluster for the header mbuf, in that case.
Bug reported at KAME environment.
Approved by: jkh
Reviewed by: sumikawa
Obtained from: KAME project
This is fix to usr.sbin/trpt and tcp_debug.[ch]
I think of putting this after 4.0 but,,,
-There was bug that when INET6 is defined,
IPv4 socket is not traced by trpt.
-I received request from a person who distribute a program
which use tcp_debug interface and print performance statistics,
that
-leave comptibility with old program as much as possible
-use same interface with other OSes
So, I talked with itojun, and synced API with netbsd IPv6 extension.
makeworld check, kernel build check(includes GENERIC) is done.
But if there happen to any problem, please let me know and
I soon backout this change.
o Drop all broadcast and multicast source addresses in tcp_input.
o Enable ICMP_BANDLIM in GENERIC.
o Change default to 200/s from 100/s. This will still stop the attack, but
is conservative enough to do this close to code freeze.
This is not the optimal patch for the problem, but is likely the least
intrusive patch that can be made for this.
Obtained from: Don Lewis and Matt Dillon.
Reviewed by: freebsd-security
for IPv4 communication.(IPv4 mapped IPv6 addr.)
Also removed IPv6 hoplimit initialization because it is alway done at
tcp_output.
Confirmed by: Bernd Walter <ticso@cicely5.cicely.de>
include this in all kernels. Declare some const *intrq_present
variables that can be checked by a module prior to using *intrq
to queue data.
Make the if_tun module capable of processing atm, ip, ip6, ipx,
natm and netatalk packets when TUNSIFHEAD is ioctl()d on.
Review not required by: freebsd-hackers
-opt_ipsec.h was missing on some tcp files (sorry for basic mistake)
-made buildable as above fix
-also added some missing IPv4 mapped IPv6 addr consideration into
ipsec4_getpolicybysock
This must be one of the reason why connections over IPsec hangs for
bigger packets.(which was reported on freebsd-current@freebsd.org)
But there still seems to be another bug and the problem is not yet fixed.
is very likely to become consensus as recent ietf/ipng mailing list
discussion. Also recent KAME repository and other KAME patched BSDs
also applied it.
s/__ss_family/ss_family/
s/__ss_len/ss_len/
Makeworld is confirmed, and no application should be affected by this change
yet.
now you can dynamically create rate-limited queues for different
flows using masks on dst/src IP, port and protocols.
Read the ipfw(8) manpage for details and examples.
Restructure the internals of the traffic shaper to use heaps,
so that it manages efficiently large number of queues.
Fix a bug which was present in the previous versions which could
cause, under certain unfrequent conditions, to send out very large
bursts of traffic.
All in all, this new code is much cleaner than the previous one and
should also perform better.
Work supported by Akamba Corp.
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.
desperation measure in low-memory situations), walk the tcpbs and
flush the reassembly queues.
This behaviour is currently controlled by the debug.do_tcpdrain sysctl
(defaults to on).
Submitted by: Bosko Milekic <bmilekic@dsuper.net>
Reviewed by: wollman
pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.
Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
to print out protocol specific pcb info.
A patch submitted by guido@gvr.org, and asmodai@wxs.nl also reported
the problem.
Thanks and sorry for your troubles.
Submitted by: guido@gvr.org
Reviewed by: shin
packet divert at kernel for IPv6/IPv4 translater daemon
This includes queue related patch submitted by jburkhol@home.com.
Submitted by: queue related patch from jburkhol@home.com
Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
the old one: an unnecessary define (KLD_MODULE) has been deleted and
the initialisation of the module is done after domaininit was called
to be sure inet is running.
Some slight changed were made to ip_auth.c and ip_state.c in order
to assure including of sys/systm.h in case we make a kld
Make sure ip_fil does nmot include osreldate in kernel mode
Remove mlfk_ipl.c from here: no sources allowed in these directories!
- Implement 'ipfw tee' (finally)
- Divert packets by calling new function divert_packet() directly instead
of going through protosw[].
- Replace kludgey global variable 'ip_divert_port' with a function parameter
to divert_packet()
- Replace kludgey global variable 'frag_divert_port' with a function parameter
to ip_reass()
- style(9) fixes
Reviewed by: julian, green
This results in closer behavior to earlier versions, where the fixed
200ms timer actually resulted in a delay anywhere from 1..200ms, with
the average delay being 100ms.
Pointed out by: dg
for IPv6 yet)
With this patch, you can assigne IPv6 addr automatically, and can reply to
IPv6 ping.
Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
to be dangerous. It will better serve us as a port building a KLD,
ala SKIP.
The hooks are staying although it would be better to port and use
the NetBSD pfil interface rather than have custom hooks.
the link are equal to the default aliasing address. Do not zero them!
This will fix the problem with non-working links added with the source
and/or aliasing address equal to the default aliasing address, but the
default aliasing address is set later, after the link has been set up,
like both natd(8) and ppp(8) do (for objective reasons).
Reviewed by: Brian Somers <brian@FreeBSD.org>,
Eivind Eklund <eivind@FreeBSD.org>,
Charles Mott <cmott@srv.net>
have been there in the first place. A GENERIC kernel shrinks almost 1k.
Add a slightly different safetybelt under nostop for tty drivers.
Add some missing FreeBSD tags
`dst_port') work for outgoing packets.
- Make permanent links whose `alias_addr' matches the primary aliasing
address `aliasAddress' work for incoming packets.
- Typo fixes.
Reviewed by: brian, eivind
Make a sonewconn3() which takes an extra argument (proc) so new sockets created
with sonewconn() from a user's system call get the correct credentials, not
just the parent's credentials.
In the words of originator:
:If an incoming connection is initiated through natd and deny_incoming is
:not set, then a new alias_link structure is created to handle the link.
:If there is nothing listening for the incoming connection, then the kernel
:responds with a RST for the connection. However, this is not processed
:correctly in libalias/alias.c:TcpMonitor{In,Out} and
:libalias/alias_db.c:SetState{In,Out} as it thinks a connection
:has been established and therefore applies a timeout of 86400 seconds
:to the link.
:
:If many of these half-connections are initiated (during, for example, a
:port scan of the host), then many thousands of unnecessary links are
:created and the resident size of natd balloons to 20MB or more.
PR: 13639
Reviewed by: brian
