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4880 commits

Author SHA1 Message Date
Eric Dumazet
8dc08ba699 ipv4: ipmr: various fixes and cleanups
1) ip_mroute_setsockopt() & ip_mroute_getsockopt() should not
   access/set raw_sk(sk)->ipmr_table before making sure the socket
   is a raw socket, and protocol is IGMP

2) MRT_INIT should return -EINVAL if optlen != sizeof(int), not
   -ENOPROTOOPT

3) MRT_ASSERT & MRT_PIM should validate optlen

4) " (v) ? 1 : 0 " can be written as " !!v "

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
Change-Id: I606493fe572b29f2c6a709833e799e20f2212882
2023-02-18 18:38:56 +01:00
Lorenzo Colitti
afd1d2b38a net: inet: Support UID-based routing in IP protocols.
- Use the UID in routing lookups made by protocol connect() and
  sendmsg() functions.
- Make sure that routing lookups triggered by incoming packets
  (e.g., Path MTU discovery) take the UID of the socket into
  account.
- For packets not associated with a userspace socket, (e.g., ping
  replies) use UID 0 inside the user namespace corresponding to
  the network namespace the socket belongs to. This allows
  all namespaces to apply routing and iptables rules to
  kernel-originated traffic in that namespaces by matching UID 0.
  This is better than using the UID of the kernel socket that is
  sending the traffic, because the UID of kernel sockets created
  at namespace creation time (e.g., the per-processor ICMP and
  TCP sockets) is the UID of the user that created the socket,
  which might not be mapped in the namespace.

Bug: 16355602
Change-Id: I910504b508948057912bc188fd1e8aca28294de3
Tested: compiles allnoconfig, allyesconfig, allmodconfig
Tested: https://android-review.googlesource.com/253302
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
2023-02-18 18:38:56 +01:00
Sabrina Dubroca
82794d1071 BACKPORT: tcp: fix recv with flags MSG_WAITALL | MSG_PEEK
Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called
with flags = MSG_WAITALL | MSG_PEEK.

sk_wait_data waits for sk_receive_queue not empty, but in this case,
the receive queue is not empty, but does not contain any skb that we
can use.

Add a "last skb seen on receive queue" argument to sk_wait_data, so
that it sleeps until the receive queue has new skbs.

Change-Id: If58492ae474effe058541f7e9a0c03dc24155393
Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258
Reported-by: Enrico Scholz <rh-bugzilla@ensc.de>
Reported-by: Dan Searle <dan@censornet.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
2023-02-18 18:36:52 +01:00
Daniel Borkmann
e9ff904465 BACKPORT: net: sock: make sock_tx_timestamp void
Currently, sock_tx_timestamp() always returns 0. The comment that
describes the sock_tx_timestamp() function wrongly says that it
returns an error when an invalid argument is passed (from commit
20d4947353, ``net: socket infrastructure for SO_TIMESTAMPING'').
Make the function void, so that we can also remove all the unneeded
if conditions that check for such a _non-existant_ error case in the
output path.

Change-Id: Ibdfd5071737190371d4abec5ae76046b5aa8de23
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
2023-02-18 18:32:19 +01:00
Eric Dumazet
cab65020e8 BACKPORT: net: include/net/sock.h cleanup
bool/const conversions where possible

__inline__ -> inline

space cleanups

Change-Id: I0ee0135e737edd702f753fac182b293ec5cc652a
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
2023-02-18 18:32:14 +01:00
Roger Hu
7c56badc9a kernel: Revert "tcp: do not lock listener to process SYN packets"
This commit belongs to the patch set (https://lwn.net/Articles/659199/)
that attempts to remove the use of locks on the socket table by
relocating the SYN table to a separate hash table and adding a spin lock
to protect the SYN request queue. Adding only this commit introduces a
race condition for LineageOS kernels for TCP listens, since the TCP SYN
data structures can be corrupted.

A TCP curl bomb on a TCP listen port will corrupt the SYN accept backlog:

for i in $(seq 1 400); do curl -x localhost:443 https://myhost.com -L  --connect-timeout 30 -o /dev/null -sS & done

Run `ss -nltp` and usually the RecVQ column does not drain to 0.

This reverts commit 7d9f104f9cabe1d72a50c4816a48f64fc1da7a64.

This really needs to be reverted across all LineageOS forks:
https://gitlab.com/LineageOS/issues/android/-/issues/3916#note_669493796

Change-Id: Ia7969aeedae411677b307a8e094f9a4cc02b801d
2022-07-05 01:10:45 -04:00
Eric Dumazet
e336f6ab76 tcp: fix more NULL deref after prequeue changes
When I cooked commit c3658e8d0f ("tcp: fix possible NULL dereference in
tcp_vX_send_reset()") I missed other spots we could deref a NULL
skb_dst(skb)

Again, if a socket is provided, we do not need skb_dst() to get a
pointer to network namespace : sock_net(sk) is good enough.

[Backport of net-next 0f85feae6b710ced3abad5b2b47d31dfcb956b62]

Bug: 16355602
Change-Id: Ibe1def7979625ee7902bff2f33ec8945b9945948
Reported-by: Dann Frazier <dann.frazier@canonical.com>
Bisected-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: ca777eff51 ("tcp: remove dst refcount false sharing for prequeue mode")
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-01-23 17:17:18 +03:00
Nicolas Dichtel
1b5c151075 xfrm: allow to avoid copying DSCP during encapsulation
By default, DSCP is copying during encapsulation.
Copying the DSCP in IPsec tunneling may be a bit dangerous because packets with
different DSCP may get reordered relative to each other in the network and then
dropped by the remote IPsec GW if the reordering becomes too big compared to the
replay window.

It is possible to avoid this copy with netfilter rules, but it's very convenient
to be able to configure it for each SA directly.

This patch adds a toogle for this purpose. By default, it's not set to maintain
backward compatibility.

Field flags in struct xfrm_usersa_info is full, hence I add a new attribute.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I885117f02790536e2c5002232b3b33be651a568d
2020-11-30 19:39:33 +03:00
David S. Miller
c275431b28 net: Document dst->obsolete better.
Add a big comment explaining how the field works, and use defines
instead of magic constants for the values assigned to it.

Suggested by Joe Perches.

Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I2c8ca84d38cd49ccc1207db588108d78e6f9403a
2020-11-30 19:39:24 +03:00
Eric Dumazet
aedce03d5d tcp: gso: fix truesize tracking
[ Upstream commit 0d08c42cf9 ]

commit 6ff50cd555 ("tcp: gso: do not generate out of order packets")
had an heuristic that can trigger a warning in skb_try_coalesce(),
because skb->truesize of the gso segments were exactly set to mss.

This breaks the requirement that

skb->truesize >= skb->len + truesizeof(struct sk_buff);

It can trivially be reproduced by :

ifconfig lo mtu 1500
ethtool -K lo tso off
netperf

As the skbs are looped into the TCP networking stack, skb_try_coalesce()
warns us of these skb under-estimating their truesize.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: Iced7cd04a2860fcc14815c4f5564e01840ac41e3
2020-11-30 19:35:22 +03:00
Eric Dumazet
33e834ef26 tcp: tsq: restore minimal amount of queueing
[ Upstream commit 98e09386c0 ]

After commit c9eeec26e3 ("tcp: TSQ can use a dynamic limit"), several
users reported throughput regressions, notably on mvneta and wifi
adapters.

802.11 AMPDU requires a fair amount of queueing to be effective.

This patch partially reverts the change done in tcp_write_xmit()
so that the minimal amount is sysctl_tcp_limit_output_bytes.

It also remove the use of this sysctl while building skb stored
in write queue, as TSO autosizing does the right thing anyway.

Users with well behaving NICS and correct qdisc (like sch_fq),
can then lower the default sysctl_tcp_limit_output_bytes value from
128KB to 8KB.

This new usage of sysctl_tcp_limit_output_bytes permits each driver
authors to check how their driver performs when/if the value is set
to a minimum of 4KB.

Normally, line rate for a single TCP flow should be possible,
but some drivers rely on timers to perform TX completion and
too long TX completion delays prevent reaching full throughput.

Fixes: c9eeec26e3 ("tcp: TSQ can use a dynamic limit")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Sujith Manoharan <sujith@msujith.org>
Reported-by: Arnaud Ebalard <arno@natisbad.org>
Tested-by: Sujith Manoharan <sujith@msujith.org>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I1fab5c795148dff3da34b42c7808476f51d99f89
2020-11-30 19:35:19 +03:00
Eric Dumazet
31089dfedf tcp: TSQ can use a dynamic limit
[ Upstream commit c9eeec26e3 ]

When TCP Small Queues was added, we used a sysctl to limit amount of
packets queues on Qdisc/device queues for a given TCP flow.

Problem is this limit is either too big for low rates, or too small
for high rates.

Now TCP stack has rate estimation in sk->sk_pacing_rate, and TSO
auto sizing, it can better control number of packets in Qdisc/device
queues.

New limit is two packets or at least 1 to 2 ms worth of packets.

Low rates flows benefit from this patch by having even smaller
number of packets in queues, allowing for faster recovery,
better RTT estimations.

High rates flows benefit from this patch by allowing more than 2 packets
in flight as we had reports this was a limiting factor to reach line
rate. [ In particular if TX completion is delayed because of coalescing
parameters ]

Example for a single flow on 10Gbp link controlled by FQ/pacing

14 packets in flight instead of 2

$ tc -s -d qd
qdisc fq 8001: dev eth0 root refcnt 32 limit 10000p flow_limit 100p
buckets 1024 quantum 3028 initial_quantum 15140
 Sent 1168459366606 bytes 771822841 pkt (dropped 0, overlimits 0
requeues 6822476)
 rate 9346Mbit 771713pps backlog 953820b 14p requeues 6822476
  2047 flow, 2046 inactive, 1 throttled, delay 15673 ns
  2372 gc, 0 highprio, 0 retrans, 9739249 throttled, 0 flows_plimit

Note that sk_pacing_rate is currently set to twice the actual rate, but
this might be refined in the future when a flow is in congestion
avoidance.

Additional change : skb->destructor should be set to tcp_wfree().

A future patch (for linux 3.13+) might remove tcp_limit_output_bytes

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I481dfb7b15ae4fc699e03e2ef846b0631c5ebb3f
2020-11-30 19:35:16 +03:00
Eric Dumazet
0cf083915c tcp: gso: do not generate out of order packets
GSO TCP handler has following issues :

1) ooo_okay from original GSO packet is duplicated to all segments
2) segments (but the last one) are orphaned, so transmit path can not
get transmit queue number from the socket. This happens if GSO
segmentation is done before stacked device for example.

Result is we can send packets from a given TCP flow to different TX
queues (if using multiqueue NICS). This generates OOO problems and
spurious SACK & retransmits.

Fix this by keeping socket pointer set for all segments.

This means that every segment must also have a destructor, and the
original gso skb truesize must be split on all segments, to keep
precise sk->sk_wmem_alloc accounting.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I9d9d4216ec24ad4091535a9b9e811760cd949825
2020-11-30 19:35:13 +03:00
Eric Dumazet
1315c0d65e tcp: tcp_tso_segment() small optimization
We can move th->check computation out of the loop, as compiler
doesn't know each skb initially share same tcp headers after
skb_segment()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I7f81480604c4bd58f5cdd0be289233b9e6142a7f
2020-11-30 19:35:10 +03:00
Eric Dumazet
2687196048 tcp: GSO should be TSQ friendly
I noticed that TSQ (TCP Small queues) was less effective when TSO is
turned off, and GSO is on. If BQL is not enabled, TSQ has then no
effect.

It turns out the GSO engine frees the original gso_skb at the time the
fragments are generated and queued to the NIC.

We should instead call the tcp_wfree() destructor for the last fragment,
to keep the flow control as intended in TSQ. This effectively limits
the number of queued packets on qdisc + NIC layers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Idbe0206447bf979e012b6c4d5fe9e4fec10d5eb8
2020-11-30 19:35:07 +03:00
Eric Dumazet
e7e3467ab1 tcp: TCP Small Queues
This introduce TSQ (TCP Small Queues)

TSQ goal is to reduce number of TCP packets in xmit queues (qdisc &
device queues), to reduce RTT and cwnd bias, part of the bufferbloat
problem.

sk->sk_wmem_alloc not allowed to grow above a given limit,
allowing no more than ~128KB [1] per tcp socket in qdisc/dev layers at a
given time.

TSO packets are sized/capped to half the limit, so that we have two
TSO packets in flight, allowing better bandwidth use.

As a side effect, setting the limit to 40000 automatically reduces the
standard gso max limit (65536) to 40000/2 : It can help to reduce
latencies of high prio packets, having smaller TSO packets.

This means we divert sock_wfree() to a tcp_wfree() handler, to
queue/send following frames when skb_orphan() [2] is called for the
already queued skbs.

Results on my dev machines (tg3/ixgbe nics) are really impressive,
using standard pfifo_fast, and with or without TSO/GSO.

Without reduction of nominal bandwidth, we have reduction of buffering
per bulk sender :
< 1ms on Gbit (instead of 50ms with TSO)
< 8ms on 100Mbit (instead of 132 ms)

I no longer have 4 MBytes backlogged in qdisc by a single netperf
session, and both side socket autotuning no longer use 4 Mbytes.

As skb destructor cannot restart xmit itself ( as qdisc lock might be
taken at this point ), we delegate the work to a tasklet. We use one
tasklest per cpu for performance reasons.

If tasklet finds a socket owned by the user, it sets TSQ_OWNED flag.
This flag is tested in a new protocol method called from release_sock(),
to eventually send new segments.

[1] New /proc/sys/net/ipv4/tcp_limit_output_bytes tunable
[2] skb_orphan() is usually called at TX completion time,
  but some drivers call it in their start_xmit() handler.
  These drivers should at least use BQL, or else a single TCP
  session can still fill the whole NIC TX ring, since TSQ will
  have no effect.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Dave Taht <dave.taht@bufferbloat.net>
Cc: Tom Herbert <therbert@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I37d5e4d7c9ced1846385b6a04ae3ad134763a949
2020-11-30 19:35:00 +03:00
Eric Dumazet
05fe7848aa tcp: fix a potential deadlock in tcp_get_info()
Taking socket spinlock in tcp_get_info() can deadlock, as
inet_diag_dump_icsk() holds the &hashinfo->ehash_locks[i],
while packet processing can use the reverse locking order.

We could avoid this locking for TCP_LISTEN states, but lockdep would
certainly get confused as all TCP sockets share same lockdep classes.

[  523.722504] ======================================================
[  523.728706] [ INFO: possible circular locking dependency detected ]
[  523.734990] 4.1.0-dbg-DEV #1676 Not tainted
[  523.739202] -------------------------------------------------------
[  523.745474] ss/18032 is trying to acquire lock:
[  523.750002]  (slock-AF_INET){+.-...}, at: [<ffffffff81669d44>] tcp_get_info+0x2c4/0x360
[  523.758129]
[  523.758129] but task is already holding lock:
[  523.763968]  (&(&hashinfo->ehash_locks[i])->rlock){+.-...}, at: [<ffffffff816bcb75>] inet_diag_dump_icsk+0x1d5/0x6c0
[  523.774661]
[  523.774661] which lock already depends on the new lock.
[  523.774661]
[  523.782850]
[  523.782850] the existing dependency chain (in reverse order) is:
[  523.790326]
-> #1 (&(&hashinfo->ehash_locks[i])->rlock){+.-...}:
[  523.796599]        [<ffffffff811126bb>] lock_acquire+0xbb/0x270
[  523.802565]        [<ffffffff816f5868>] _raw_spin_lock+0x38/0x50
[  523.808628]        [<ffffffff81665af8>] __inet_hash_nolisten+0x78/0x110
[  523.815273]        [<ffffffff816819db>] tcp_v4_syn_recv_sock+0x24b/0x350
[  523.822067]        [<ffffffff81684d41>] tcp_check_req+0x3c1/0x500
[  523.828199]        [<ffffffff81682d09>] tcp_v4_do_rcv+0x239/0x3d0
[  523.834331]        [<ffffffff816842fe>] tcp_v4_rcv+0xa8e/0xc10
[  523.840202]        [<ffffffff81658fa3>] ip_local_deliver_finish+0x133/0x3e0
[  523.847214]        [<ffffffff81659a9a>] ip_local_deliver+0xaa/0xc0
[  523.853440]        [<ffffffff816593b8>] ip_rcv_finish+0x168/0x5c0
[  523.859624]        [<ffffffff81659db7>] ip_rcv+0x307/0x420

Lets use u64_sync infrastructure instead. As a bonus, 64bit
arches get optimized, as these are nop for them.

Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I50c833b77f41111a6fa3a57834c6311f95573754
2020-11-30 19:31:51 +03:00
Marcelo Ricardo Leitner
461a9cb3c4 tcp: add tcpi_segs_in and tcpi_segs_out to tcp_info
This patch tracks the total number of inbound and outbound segments on a
TCP socket. One may use this number to have an idea on connection
quality when compared against the retransmissions.

RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut

These are a 32bit field each and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->segs_out was placed near tp->snd_nxt for good data
locality and minimal performance impact, while tp->segs_in was placed
near tp->bytes_received for the same reason.

Join work with Eric Dumazet.

Note that received SYN are accounted on the listener, but sent SYNACK
are not accounted.

Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Ic3e5daea102e13fb24c5fb1ce6913d5ece13c521
2020-11-30 19:31:48 +03:00
Eric Dumazet
2afbb021d9 tcp: add tcpi_bytes_received to tcp_info
This patch tracks total number of payload bytes received on a TCP socket.
This is the sum of all changes done to tp->rcv_nxt

RFC4898 named this : tcpEStatsAppHCThruOctetsReceived

This is a 64bit field, and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->bytes_received was placed near tp->rcv_nxt for
best data locality and minimal performance impact.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Eric Salo <salo@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Ie1fec6455c8c6cf9ae3e2df09bf55abb56b57286
2020-11-30 19:31:44 +03:00
Eric Dumazet
45970b0b74 tcp: add tcpi_bytes_acked to tcp_info
This patch tracks total number of bytes acked for a TCP socket.
This is the sum of all changes done to tp->snd_una, and allows
for precise tracking of delivered data.

RFC4898 named this : tcpEStatsAppHCThruOctetsAcked

This is a 64bit field, and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->bytes_acked was placed near tp->snd_una for
best data locality and minimal performance impact.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Eric Salo <salo@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I975b11b049d6bde1b6802dc4331a9da93c371c9b
2020-11-30 19:31:41 +03:00
Eric Dumazet
3e12c5a9d4 tcp: add pacing_rate information into tcp_info
Add two new fields to struct tcp_info, to report sk_pacing_rate
and sk_max_pacing_rate to monitoring applications, as ss from iproute2.

User exported fields are 64bit, even if kernel is currently using 32bit
fields.

lpaa5:~# ss -i
..
	 skmem:(r0,rb357120,t0,tb2097152,f1584,w1980880,o0,bl0) ts sack cubic
wscale:6,6 rto:400 rtt:0.875/0.75 mss:1448 cwnd:1 ssthresh:12 send
13.2Mbps pacing_rate 3336.2Mbps unacked:15 retrans:1/5448 lost:15
rcv_space:29200

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I31149707ef565448d5f2f1b43f5759f308f824f5
2020-11-30 19:31:38 +03:00
Eric Dumazet
adc3caedd0 net: introduce SO_MAX_PACING_RATE
As mentioned in commit afe4fd0624 ("pkt_sched: fq: Fair Queue packet
scheduler"), this patch adds a new socket option.

SO_MAX_PACING_RATE offers the application the ability to cap the
rate computed by transport layer. Value is in bytes per second.

u32 val = 1000000;
setsockopt(sockfd, SOL_SOCKET, SO_MAX_PACING_RATE, &val, sizeof(val));

To be effectively paced, a flow must use FQ packet scheduler.

Note that a packet scheduler takes into account the headers for its
computations. The effective payload rate depends on MSS and retransmits
if any.

I chose to make this pacing rate a SOL_SOCKET option instead of a
TCP one because this can be used by other protocols.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Iea51b6104a5420d5c9ed1ea7382cbd53bdb8f4be
2020-11-30 19:31:32 +03:00
Eric Dumazet
e5a9f4f1cc tcp: TSO packets automatic sizing
After hearing many people over past years complaining against TSO being
bursty or even buggy, we are proud to present automatic sizing of TSO
packets.

One part of the problem is that tcp_tso_should_defer() uses an heuristic
relying on upcoming ACKS instead of a timer, but more generally, having
big TSO packets makes little sense for low rates, as it tends to create
micro bursts on the network, and general consensus is to reduce the
buffering amount.

This patch introduces a per socket sk_pacing_rate, that approximates
the current sending rate, and allows us to size the TSO packets so
that we try to send one packet every ms.

This field could be set by other transports.

Patch has no impact for high speed flows, where having large TSO packets
makes sense to reach line rate.

For other flows, this helps better packet scheduling and ACK clocking.

This patch increases performance of TCP flows in lossy environments.

A new sysctl (tcp_min_tso_segs) is added, to specify the
minimal size of a TSO packet (default being 2).

A follow-up patch will provide a new packet scheduler (FQ), using
sk_pacing_rate as an input to perform optional per flow pacing.

This explains why we chose to set sk_pacing_rate to twice the current
rate, allowing 'slow start' ramp up.

sk_pacing_rate = 2 * cwnd * mss / srtt

v2: Neal Cardwell reported a suspect deferring of last two segments on
initial write of 10 MSS, I had to change tcp_tso_should_defer() to take
into account tp->xmit_size_goal_segs

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Van Jacobson <vanj@google.com>
Cc: Tom Herbert <therbert@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: If293e2c6a0f52fe0e2b4ee149c9242f8c5e46ef5
2020-11-30 19:30:45 +03:00
Eric W. Biederman
ec0a45cd4a net: Replace u64_stats_fetch_begin_bh to u64_stats_fetch_begin_irq
Replace the bh safe variant with the hard irq safe variant.

We need a hard irq safe variant to deal with netpoll transmitting
packets from hard irq context, and we need it in most if not all of
the places using the bh safe variant.

Except on 32bit uni-processor the code is exactly the same so don't
bother with a bh variant, just have a hard irq safe variant that
everyone can use.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[javelinanddart]: Merge conflicts were resolved for drivers that exist in 3.4,
and additionally a treewide find and replace was run for these functions.
Signed-off-by: Paul Keith <javelinanddart@gmail.com>
Change-Id: Ib74db793de5e546414a0599f23095f82f0e20c86
2020-11-30 19:26:49 +03:00
John Stultz
ad74346428 net: Explicitly initialize u64_stats_sync structures for lockdep
In order to enable lockdep on seqcount/seqlock structures, we
must explicitly initialize any locks.

The u64_stats_sync structure, uses a seqcount, and thus we need
to introduce a u64_stats_init() function and use it to initialize
the structure.

This unfortunately adds a lot of fairly trivial initialization code
to a number of drivers. But the benefit of ensuring correctness makes
this worth while.

Because these changes are required for lockdep to be enabled, and the
changes are quite trivial, I've not yet split this patch out into 30-some
separate patches, as I figured it would be better to get the various
maintainers thoughts on how to best merge this change along with
the seqcount lockdep enablement.

Feedback would be appreciated!

Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Jesse Gross <jesse@nicira.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Roger Luethi <rl@hellgate.ch>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Simon Horman <horms@verge.net.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Wensong Zhang <wensong@linux-vs.org>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Change-Id: Ieda06b95f0ec302dbef8576ef4c8fb4bd28ffb2f
2020-11-30 19:26:40 +03:00
Stephen Hemminger
39b326bec0 tcp: remove Appropriate Byte Count support
TCP Appropriate Byte Count was added by me, but later disabled.
There is no point in maintaining it since it is a potential source
of bugs and Linux already implements other better window protection
heuristics.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Ifc93fa043256c275580a9f93611ad1d013889bc4
2020-11-30 19:26:36 +03:00
stephen hemminger
a9d180c942 tunnel: implement 64 bits statistics
Convert the per-cpu statistics kept for GRE, IPIP, and SIT tunnels
to use 64 bit statistics.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Keith <javelinanddart@gmail.com>
Change-Id: I317ad78a7f3a31326a1bc6f3069712f348b38a6c
2020-11-30 19:26:33 +03:00
Luca Weiss
e4cede11f4 ipv4: Pass struct flowi4 directly to rt_fill_info
This is partly a backport of d6c0a4f609
  (ipv4: Kill 'rt_src' from 'struct rtable').

skb->sk can be null, and in fact it is when creating the buffer
in inet_rtm_getroute. There is no other way of accessing the flow,
so pass it directly.

Fixes invalid memory address when running 'ip route get $IPADDR'

Change-Id: I7b9e5499614b96360c9c8420907e82e145bb97f3
2020-10-25 02:37:54 -04:00
Florian Westphal
0edd378e5e netfilter: xt_rpfilter: depend on raw or mangle table
rpfilter is only valid in raw/mangle PREROUTING, i.e.
RPFILTER=y|m is useless without raw or mangle table support.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I26118146ace6e802b5700472222198ef31f9d562
2018-12-07 22:04:24 +04:00
Gao feng
93ca5c0e51 netfilter: use IS_ENABLE to replace if defined in TRACE target
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: If9b17fcdb53091906a15512e6cb74a210a0cd93f
2018-12-07 22:04:24 +04:00
Eric W. Biederman
27845b8f9f net: Allow userns root to control ipv4
Allow an unpriviled user who has created a user namespace, and then
created a network namespace to effectively use the new network
namespace, by reducing capable(CAP_NET_ADMIN) and
capable(CAP_NET_RAW) calls to be ns_capable(net->user_ns,
CAP_NET_ADMIN), or capable(net->user_ns, CAP_NET_RAW) calls.

Settings that merely control a single network device are allowed.
Either the network device is a logical network device where
restrictions make no difference or the network device is hardware NIC
that has been explicity moved from the initial network namespace.

In general policy and network stack state changes are allowed
while resource control is left unchanged.

Allow creating raw sockets.
Allow the SIOCSARP ioctl to control the arp cache.
Allow the SIOCSIFFLAG ioctl to allow setting network device flags.
Allow the SIOCSIFADDR ioctl to allow setting a netdevice ipv4 address.
Allow the SIOCSIFBRDADDR ioctl to allow setting a netdevice ipv4 broadcast address.
Allow the SIOCSIFDSTADDR ioctl to allow setting a netdevice ipv4 destination address.
Allow the SIOCSIFNETMASK ioctl to allow setting a netdevice ipv4 netmask.
Allow the SIOCADDRT and SIOCDELRT ioctls to allow adding and deleting ipv4 routes.

Allow the SIOCADDTUNNEL, SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls for
adding, changing and deleting gre tunnels.

Allow the SIOCADDTUNNEL, SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls for
adding, changing and deleting ipip tunnels.

Allow the SIOCADDTUNNEL, SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls for
adding, changing and deleting ipsec virtual tunnel interfaces.

Allow setting the MRT_INIT, MRT_DONE, MRT_ADD_VIF, MRT_DEL_VIF, MRT_ADD_MFC,
MRT_DEL_MFC, MRT_ASSERT, MRT_PIM, MRT_TABLE socket options on multicast routing
sockets.

Allow setting and receiving IPOPT_CIPSO, IP_OPT_SEC, IP_OPT_SID and
arbitrary ip options.

Allow setting IP_SEC_POLICY/IP_XFRM_POLICY ipv4 socket option.
Allow setting the IP_TRANSPARENT ipv4 socket option.
Allow setting the TCP_REPAIR socket option.
Allow setting the TCP_CONGESTION socket option.

Change-Id: I3b6ce2465e354cd2865e1a7fe67d6e812f88b16a
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 22:04:24 +04:00
Andrew Collins
d4739bc9f5 netfilter: nf_nat: Also handle non-ESTABLISHED routing changes in MASQUERADE
Since (a0ecb85 netfilter: nf_nat: Handle routing changes in MASQUERADE
target), the MASQUERADE target handles routing changes which affect
the output interface of a connection, but only for ESTABLISHED
connections.  It is also possible for NEW connections which
already have a conntrack entry to be affected by routing changes.

This adds a check to drop entries in the NEW+conntrack state
when the oif has changed.

Signed-off-by: Andrew Collins <bsderandrew@gmail.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I6ae5c391d502f44cebc0563f51f4a65667efd0ae
2018-12-07 22:02:09 +04:00
Mukund Jampala
1b6cc2ac53 netfilter: ip[6]t_REJECT: fix wrong transport header pointer in TCP reset
The problem occurs when iptables constructs the tcp reset packet.
It doesn't initialize the pointer to the tcp header within the skb.
When the skb is passed to the ixgbe driver for transmit, the ixgbe
driver attempts to access the tcp header and crashes.
Currently, other drivers (such as our 1G e1000e or igb drivers) don't
access the tcp header on transmit unless the TSO option is turned on.

<1>BUG: unable to handle kernel NULL pointer dereference at 0000000d
<1>IP: [<d081621c>] ixgbe_xmit_frame_ring+0x8cc/0x2260 [ixgbe]
<4>*pdpt = 0000000085e5d001 *pde = 0000000000000000
<0>Oops: 0000 [#1] SMP
[...]
<4>Pid: 0, comm: swapper Tainted: P            2.6.35.12 #1 Greencity/Thurley
<4>EIP: 0060:[<d081621c>] EFLAGS: 00010246 CPU: 16
<4>EIP is at ixgbe_xmit_frame_ring+0x8cc/0x2260 [ixgbe]
<4>EAX: c7628820 EBX: 00000007 ECX: 00000000 EDX: 00000000
<4>ESI: 00000008 EDI: c6882180 EBP: dfc6b000 ESP: ced95c48
<4> DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
<0>Process swapper (pid: 0, ti=ced94000 task=ced73bd0 task.ti=ced94000)
<0>Stack:
<4> cbec7418 c779e0d8 c77cc888 c77cc8a8 0903010a 00000000 c77c0008 00000002
<4><0> cd4997c0 00000010 dfc6b000 00000000 d0d176c9 c77cc8d8 c6882180 cbec7318
<4><0> 00000004 00000004 cbec7230 cbec7110 00000000 cbec70c0 c779e000 00000002
<0>Call Trace:
<4> [<d0d176c9>] ? 0xd0d176c9
<4> [<d0d18a4d>] ? 0xd0d18a4d
<4> [<411e243e>] ? dev_hard_start_xmit+0x218/0x2d7
<4> [<411f03d7>] ? sch_direct_xmit+0x4b/0x114
<4> [<411f056a>] ? __qdisc_run+0xca/0xe0
<4> [<411e28b0>] ? dev_queue_xmit+0x2d1/0x3d0
<4> [<411e8120>] ? neigh_resolve_output+0x1c5/0x20f
<4> [<411e94a1>] ? neigh_update+0x29c/0x330
<4> [<4121cf29>] ? arp_process+0x49c/0x4cd
<4> [<411f80c9>] ? nf_hook_slow+0x3f/0xac
<4> [<4121ca8d>] ? arp_process+0x0/0x4cd
<4> [<4121ca8d>] ? arp_process+0x0/0x4cd
<4> [<4121c6d5>] ? T.901+0x38/0x3b
<4> [<4121c918>] ? arp_rcv+0xa3/0xb4
<4> [<4121ca8d>] ? arp_process+0x0/0x4cd
<4> [<411e1173>] ? __netif_receive_skb+0x32b/0x346
<4> [<411e19e1>] ? netif_receive_skb+0x5a/0x5f
<4> [<411e1ea9>] ? napi_skb_finish+0x1b/0x30
<4> [<d0816eb4>] ? ixgbe_xmit_frame_ring+0x1564/0x2260 [ixgbe]
<4> [<41013468>] ? lapic_next_event+0x13/0x16
<4> [<410429b2>] ? clockevents_program_event+0xd2/0xe4
<4> [<411e1b03>] ? net_rx_action+0x55/0x127
<4> [<4102da1a>] ? __do_softirq+0x77/0xeb
<4> [<4102dab1>] ? do_softirq+0x23/0x27
<4> [<41003a67>] ? do_IRQ+0x7d/0x8e
<4> [<41002a69>] ? common_interrupt+0x29/0x30
<4> [<41007bcf>] ? mwait_idle+0x48/0x4d
<4> [<4100193b>] ? cpu_idle+0x37/0x4c
<0>Code: df 09 d7 0f 94 c2 0f b6 d2 e9 e7 fb ff ff 31 db 31 c0 e9 38
ff ff ff 80 78 06 06 0f 85 3e fb ff ff 8b 7c 24 38 8b 8f b8 00 00 00
<0f> b6 51 0d f6 c2 01 0f 85 27 fb ff ff 80 e2 02 75 0d 8b 6c 24
<0>EIP: [<d081621c>] ixgbe_xmit_frame_ring+0x8cc/0x2260 [ixgbe] SS:ESP

Signed-off-by: Mukund Jampala <jbmukund@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I4866944d4992f703e55afcb20e9746a416d3d498
2018-12-07 22:02:09 +04:00
Jozsef Kadlecsik
2e46149f8c netfilter: nf_nat: Handle routing changes in MASQUERADE target
When the route changes (backup default route, VPNs) which affect a
masqueraded target, the packets were sent out with the outdated source
address. The patch addresses the issue by comparing the outgoing interface
directly with the masqueraded interface in the nat table.

Events are inefficient in this case, because it'd require adding route
events to the network core and then scanning the whole conntrack table
and re-checking the route for all entry.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I148103e8a4b257d004b8f0f03455243a28ff0eec
2018-12-07 22:02:09 +04:00
Patrick McHardy
dd6490947e netfilter: ip6tables: add MASQUERADE target
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change-Id: I2296776746567afe4f8067628308c88ba2233e5c
2018-12-07 22:02:09 +04:00
Patrick McHardy
d1e8c3336e ipv4: fix path MTU discovery with connection tracking
IPv4 conntrack defragments incoming packet at the PRE_ROUTING hook and
(in case of forwarded packets) refragments them at POST_ROUTING
independent of the IP_DF flag. Refragmentation uses the dst_mtu() of
the local route without caring about the original fragment sizes,
thereby breaking PMTUD.

This patch fixes this by keeping track of the largest received fragment
with IP_DF set and generates an ICMP fragmentation required error during
refragmentation if that size exceeds the MTU.

Change-Id: Ibac77b728baba05841286ea5a8a2089d56e6ad65
Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
057e9ad3b0 netfilter: nf_nat: support IPv6 in TFTP NAT helper
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change-Id: If5534638ee9e5d2083eb503ce4e94777e9889876
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
0462c8af52 netfilter: nf_nat: support IPv6 in IRC NAT helper
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change-Id: Iba939b75c976019614c616e28bbca6b5457fada8
2018-12-07 22:02:09 +04:00
Patrick McHardy
d484ac1667 netfilter: nf_nat: support IPv6 in SIP NAT helper
Add IPv6 support to the SIP NAT helper. There are no functional differences
to IPv4 NAT, just different formats for addresses.

Change-Id: I151f527731d4724606203ca82244b5aad4b9e026
Signed-off-by: Patrick McHardy <kaber@trash.net>
2018-12-07 22:02:09 +04:00
Patrick McHardy
39cce7ba50 netfilter: nf_nat: support IPv6 in amanda NAT helper
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change-Id: I52b59bcdfbff5ad94cfda035cd965c3f89cede9d
2018-12-07 22:02:09 +04:00
Patrick McHardy
0d2cb57410 netfilter: nf_nat: support IPv6 in FTP NAT helper
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change-Id: Ieed29cda783b6ad03cb7a4a1a6b594cf4503007c
2018-12-07 22:02:09 +04:00
Patrick McHardy
7ce958755b netfilter: add protocol independent NAT core
Convert the IPv4 NAT implementation to a protocol independent core and
address family specific modules.

Change-Id: I926b42af53b37c96fb654021e7f568450e8c63c0
Signed-off-by: Patrick McHardy <kaber@trash.net>
2018-12-07 22:02:09 +04:00
Patrick McHardy
d7349a49b5 netfilter: nf_nat: add protoff argument to packet mangling functions
For mangling IPv6 packets the protocol header offset needs to be known
by the NAT packet mangling functions. Add a so far unused protoff argument
and convert the conntrack and NAT helpers to use it in preparation of
IPv6 NAT.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Change-Id: I34f8597c072b0e9d99d19ae958c1788e3d8d51ee
2018-12-07 22:02:09 +04:00
Patrick McHardy
b9df259c9b netfilter: nf_ct_sip: fix IPv6 address parsing
Within SIP messages IPv6 addresses are enclosed in square brackets in most
cases, with the exception of the "received=" header parameter. Currently
the helper fails to parse enclosed addresses.

This patch:

- changes the SIP address parsing function to enforce square brackets
  when required, and accept them when not required but present, as
  recommended by RFC 5118.

- adds a new SDP address parsing function that never accepts square
  brackets since SDP doesn't use them.

With these changes, the SIP helper correctly parses all test messages
from RFC 5118 (Session Initiation Protocol (SIP) Torture Test Messages
for Internet Protocol Version 6 (IPv6)).

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I269237f68085de081ad6b3779f9806cd8380bbc9
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
b3bc43d3b7 netfilter: nfnetlink_queue: fix compilation with CONFIG_NF_NAT=m and CONFIG_NF_CT_NETLINK=y
LD      init/built-in.o
net/built-in.o:(.data+0x4408): undefined reference to `nf_nat_tcp_seq_adjust'
make: *** [vmlinux] Error 1

This patch adds a new pointer hook (nfq_ct_nat_hook) similar to other existing
in Netfilter to solve our complicated configuration dependencies.

Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I332521b61f008793381ba6eeb3d3a34369adaea7
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
678d79d6bc netfilter: nf_ct_helper: implement variable length helper private data
This patch uses the new variable length conntrack extensions.

Instead of using union nf_conntrack_help that contain all the
helper private data information, we allocate variable length
area to store the private helper data.

This patch includes the modification of all existing helpers.
It also includes a couple of include header to avoid compilation
warnings.

Change-Id: I2b855f3687c16ac0996053006d0543ad05411acd
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
26948d946b netfilter: nfnetlink_queue: add NAT TCP sequence adjustment if packet mangled
User-space programs that receive traffic via NFQUEUE may mangle packets.
If NAT is enabled, this usually puzzles sequence tracking, leading to
traffic disruptions.

With this patch, nfnl_queue will make the corresponding NAT TCP sequence
adjustment if:

1) The packet has been mangled,
2) the NFQA_CFG_F_CONNTRACK flag has been set, and
3) NAT is detected.

There are some records on the Internet complaning about this issue:
http://stackoverflow.com/questions/260757/packet-mangling-utilities-besides-iptables

By now, we only support TCP since we have no helpers for DCCP or SCTP.
Better to add this if we ever have some helper over those layer 4 protocols.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: Id74b2db6fa3264a322d682b64a3104ce6ff42eaf
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
191c3003e8 netfilter: add user-space connection tracking helper infrastructure
There are good reasons to supports helpers in user-space instead:

* Rapid connection tracking helper development, as developing code
  in user-space is usually faster.

* Reliability: A buggy helper does not crash the kernel. Moreover,
  we can monitor the helper process and restart it in case of problems.

* Security: Avoid complex string matching and mangling in kernel-space
  running in privileged mode. Going further, we can even think about
  running user-space helpers as a non-root process.

* Extensibility: It allows the development of very specific helpers (most
  likely non-standard proprietary protocols) that are very likely not to be
  accepted for mainline inclusion in the form of kernel-space connection
  tracking helpers.

This patch adds the infrastructure to allow the implementation of
user-space conntrack helpers by means of the new nfnetlink subsystem
`nfnetlink_cthelper' and the existing queueing infrastructure
(nfnetlink_queue).

I had to add the new hook NF_IP6_PRI_CONNTRACK_HELPER to register
ipv[4|6]_helper which results from splitting ipv[4|6]_confirm into
two pieces. This change is required not to break NAT sequence
adjustment and conntrack confirmation for traffic that is enqueued
to our user-space conntrack helpers.

Basic operation, in a few steps:

1) Register user-space helper by means of `nfct':

 nfct helper add ftp inet tcp

 [ It must be a valid existing helper supported by conntrack-tools ]

2) Add rules to enable the FTP user-space helper which is
   used to track traffic going to TCP port 21.

For locally generated packets:

 iptables -I OUTPUT -t raw -p tcp --dport 21 -j CT --helper ftp

For non-locally generated packets:

 iptables -I PREROUTING -t raw -p tcp --dport 21 -j CT --helper ftp

3) Run the test conntrackd in helper mode (see example files under
   doc/helper/conntrackd.conf

 conntrackd

4) Generate FTP traffic going, if everything is OK, then conntrackd
   should create expectations (you can check that with `conntrack':

 conntrack -E expect

    [NEW] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp
[DESTROY] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp

This confirms that our test helper is receiving packets including the
conntrack information, and adding expectations in kernel-space.

The user-space helper can also store its private tracking information
in the conntrack structure in the kernel via the CTA_HELP_INFO. The
kernel will consider this a binary blob whose layout is unknown. This
information will be included in the information that is transfered
to user-space via glue code that integrates nfnetlink_queue and
ctnetlink.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: Ifad12a30d86a6eb0b72d20f079336a24348d711b
2018-12-07 22:02:09 +04:00
Pablo Neira Ayuso
a2688d5375 netfilter: remove ip_queue support
This patch removes ip_queue support which was marked as obsolete
years ago. The nfnetlink_queue modules provides more advanced
user-space packet queueing mechanism.

This patch also removes capability code included in SELinux that
refers to ip_queue. Otherwise, we break compilation.

Several warning has been sent regarding this to the mailing list
in the past month without anyone rising the hand to stop this
with some strong argument.

Change-Id: I62ab355af31e708b3c1000f2252c8196fb8ba428
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-07 22:00:11 +04:00
Johannes Berg
f3fab131f3 ipv4: add option to drop gratuitous ARP packets
In certain 802.11 wireless deployments, there will be ARP proxies
that use knowledge of the network to correctly answer requests.
To prevent gratuitous ARP frames on the shared medium from being
a problem, on such deployments wireless needs to drop them.

Enable this by providing an option called "drop_gratuitous_arp".

Change-Id: Ic0ed4c7e520b1d973eb1ae206af0f882badc21ce
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 21:59:38 +04:00