netfilter: nf_conntrack_sip: fix the ct_sip_parse_numerical_param() return value.

ct_sip_parse_numerical_param() returns only 0 or 1 now.
But process_register_request() and process_register_response() imply
checking for a negative value if parsing of a numerical header parameter
failed.
The invocation in nf_nat_sip() looks correct:
if (ct_sip_parse_numerical_param(...) > 0 &&
...) { ... }

Make the return value of the function ct_sip_parse_numerical_param()
a tristate to fix all the cases
a) return 1 if value is found; *val is set
b) return 0 if value is not found; *val is unchanged
c) return -1 on error; *val is undefined

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.

Fixes: 0f32a40fc91a ("[NETFILTER]: nf_conntrack_sip: create signalling expectations")
Signed-off-by: Ilia.Gavrilov <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: fix ct_sip_walk_headers

ct_sip_next_header and ct_sip_get_header return an absolute
value of matchoff, not a shift from current dataoff.
So dataoff should be assigned matchoff, not incremented by it.

This issue can be seen in the scenario when there are multiple
Contact headers and the first one is using a hostname and other headers
use IP addresses. In this case, ct_sip_walk_headers will work as follows:

The first ct_sip_get_header call to will find the first Contact header
but will return -1 as the header uses a hostname. But matchoff will
be changed to the offset of this header. After that, dataoff should be
set to matchoff, so that the next ct_sip_get_header call find the next
Contact header. But instead of assigning dataoff to matchoff, it is
incremented by it, which is not correct, as matchoff is an absolute
value of the offset. So on the next call to the ct_sip_get_header,
dataoff will be incorrect, and the next Contact header may not be
found at all.

Fixes: 05e3ced297fe ("[NETFILTER]: nf_conntrack_sip: introduce SIP-URI parsing helper")
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

netfilter: nf_conntrack: use rcu accessors where needed

Sparse complains about direct access to the 'helper' and timeout members.
Both have __rcu annotation, so use the accessors.

xt_CT is fine, accesses occur before the structure is visible to other
cpus. Switch to rcu accessors there as well to reduce noise.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: add missing __rcu annotations

Access to the hook pointers use correct helpers but the pointers lack
the needed __rcu annotation.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: fix expectation clash

When conntracks change during a dialog, SDP messages may be sent from
different conntracks to establish expects with identical tuples. In this
case expects conflict may be detected for the 2nd SDP message and end up
with a process failure.

The fixing here is to reuse an existing expect who has the same tuple for a
different conntrack if any.

Here are two scenarios for the case.

1)
SERVER CPE

| INVITE SDP |
5060 |<----------------------|5060
| 100 Trying |
5060 |---------------------->|5060
| 183 SDP |
5060 |---------------------->|5060 ===> Conntrack 1
| PRACK |
50601 |<----------------------|5060
| 200 OK (PRACK) |
50601 |---------------------->|5060
| 200 OK (INVITE) |
5060 |---------------------->|5060
| ACK |
50601 |<----------------------|5060
| |
|<--- RTP stream ------>|
| |
| INVITE SDP (t38) |
50601 |---------------------->|5060 ===> Conntrack 2

With a certain configuration in the CPE, SIP messages "183 with SDP" and
"re-INVITE with SDP t38" will go through the sip helper to create
expects for RTP and RTCP.

It is okay to create RTP and RTCP expects for "183", whose master
connection source port is 5060, and destination port is 5060.

In the "183" message, port in Contact header changes to 50601 (from the
original 5060). So the following requests e.g. PRACK and ACK are sent to
port 50601. It is a different conntrack (let call Conntrack 2) from the
original INVITE (let call Conntrack 1) due to the port difference.

In this example, after the call is established, there is RTP stream but no
RTCP stream for Conntrack 1, so the RTP expect created upon "183" is
cleared, and RTCP expect created for Conntrack 1 retains.

When "re-INVITE with SDP t38" arrives to create RTP&RTCP expects, current
ALG implementation will call nf_ct_expect_related() for RTP and RTCP. The
expects tuples are identical to those for Conntrack 1. RTP expect for
Conntrack 2 succeeds in creation as the one for Conntrack 1 has been
removed. RTCP expect for Conntrack 2 fails in creation because it has
idential tuples and 'conflict' with the one retained for Conntrack 1. And
then result in a failure in processing of the re-INVITE.

2)

SERVER A CPE

| REGISTER |
5060 |<------------------| 5060 ==> CT1
| 200 |
5060 |------------------>| 5060
| |
| INVITE SDP(1) |
5060 |<------------------| 5060
| 300(multi choice) |
5060 |------------------>| 5060 SERVER B
| ACK |
5060 |<------------------| 5060
| INVITE SDP(2) |
5060 |-------------------->| 5060 ==> CT2
| 100 |
5060 |<--------------------| 5060
| 200(contact changes)|
5060 |<--------------------| 5060
| ACK |
5060 |-------------------->| 50601 ==> CT3
| |
|<--- RTP stream ---->|
| |
| BYE |
5060 |<--------------------| 50601
| 200 |
5060 |-------------------->| 50601
| INVITE SDP(3) |
5060 |<------------------| 5060 ==> CT1

CPE sends an INVITE request(1) to Server A, and creates a RTP&RTCP expect
pair for this Conntrack 1 (CT1). Server A responds 300 to redirect to
Server B. The RTP&RTCP expect pairs created on CT1 are removed upon 300
response.

CPE sends the INVITE request(2) to Server B, and creates an expect pair
for the new conntrack (due to destination address difference), let call
CT2. Server B changes the port to 50601 in 200 OK response, and the
following requests ACK and BYE from CPE are sent to 50601. The call is
established. There is RTP stream and no RTCP stream. So RTP expect is
removed and RTCP expect for CT2 retains.

As BYE request is sent from port 50601, it is another conntrack, let call
CT3, different from CT2 due to the port difference. So the BYE request will
not remove the RTCP expect for CT2.

Then another outgoing call is made, with the same RTP port being used (not
definitely but possibly). CPE firstly sends the INVITE request(3) to Server
A, and tries to create a RTP&RTCP expect pairs for this CT1. In current ALG
implementation, the RTCP expect for CT1 fails in creation because it
'conflicts' with the residual one for CT2. As a result the INVITE request
fails to send.

Signed-off-by: xiao ruizhu <katrina.xiaorz@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netfilter: add API to manage NAT helpers.

The API allows a conntrack helper to indicate its corresponding
NAT helper which then can be loaded and reference counted.

Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: replace NF_NAT_NEEDED with IS_ENABLED(CONFIG_NF_NAT)

NF_NAT_NEEDED is true whenever nat support for either ipv4 or ipv6 is
enabled. Now that the af-specific nat configuration switches have been
removed, IS_ENABLED(CONFIG_NF_NAT) has the same effect.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: remove direct dependency on IPv6

Previous implementation was not usable with CONFIG_IPV6=m.

Fixes: a3419ce3356c ("netfilter: nf_conntrack_sip: add sip_external_media logic")
Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: add sip_external_media logic

When enabled, the sip_external_media logic will leave SDP
payload untouched when it detects that interface towards INVITEd
party is the same with the one towards media endpoint.

The typical scenario for this logic is when a LAN SIP agent has more
than one IP address (uses a different address for media streams than
the one used on signalling stream) and it also forwards calls to a
voice mailbox located on the WAN side. In such case sip_direct_media
must be disabled (so normal calls could be handled by the SIP
helper), but media streams that are not traversing this router must
also be excluded from address translation (e.g. call forwards).

Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: add __exit mark to helper modules

There are no __exit mark in the helper modules.
because these exit functions used to be called by init function
but now that is not. so we can add __exit mark.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: allow duplicate SDP expectations

Callum Sinclair reported SIP IP Phone errors that he tracked down to
such phones sending session descriptions for different media types but
with same port numbers.

The expect core will only 'refresh' existing expectation if it is
from same master AND same expectation class (media type).
As expectation class is different, we get an error.

The SIP connection tracking code will then

1). drop the SDP packet
2). if an rtp expectation was already installed successfully,
error on rtcp expectation will cancel the rtp one.

Make the expect core report back to caller when the conflict is due
to different expectation class and have SIP tracker ignore soft-error.

Reported-by: Callum Sinclair <Callum.Sinclair@alliedtelesis.co.nz>
Tested-by: Callum Sinclair <Callum.Sinclair@alliedtelesis.co.nz>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Remove duplicated rcu_read_lock.

This patch removes duplicate rcu_read_lock().

1. IPVS part:

According to Julian Anastasov's mention, contexts of ipvs are described
at: http://marc.info/?l=netfilter-devel&m=149562884514072&w=2, in summary:

- packet RX/TX: does not need locks because packets come from hooks.
- sync msg RX: backup server uses RCU locks while registering new
connections.
- ip_vs_ctl.c: configuration get/set, RCU locks needed.
- xt_ipvs.c: It is a netfilter match, running from hook context.

As result, rcu_read_lock and rcu_read_unlock can be removed from:

- ip_vs_core.c: all
- ip_vs_ctl.c:
- only from ip_vs_has_real_service
- ip_vs_ftp.c: all
- ip_vs_proto_sctp.c: all
- ip_vs_proto_tcp.c: all
- ip_vs_proto_udp.c: all
- ip_vs_xmit.c: all (contains only packet processing)

2. Netfilter part:

There are three types of functions that are guaranteed the rcu_read_lock().
First, as result, functions are only called by nf_hook():

- nf_conntrack_broadcast_help(), pptp_expectfn(), set_expected_rtp_rtcp().
- tcpmss_reverse_mtu(), tproxy_laddr4(), tproxy_laddr6().
- match_lookup_rt6(), check_hlist(), hashlimit_mt_common().
- xt_osf_match_packet().

Second, functions that caller already held the rcu_read_lock().
- destroy_conntrack(), ctnetlink_conntrack_event().
- ctnl_timeout_find_get(), nfqnl_nf_hook_drop().

Third, functions that are mixed with type1 and type2.

These functions are called by nf_hook() also these are called by
ordinary functions that already held the rcu_read_lock():

- __ctnetlink_glue_build(), ctnetlink_expect_event().
- ctnetlink_proto_size().

Applied files are below:

- nf_conntrack_broadcast.c, nf_conntrack_core.c, nf_conntrack_netlink.c.
- nf_conntrack_pptp.c, nf_conntrack_sip.c, nfnetlink_cttimeout.c.
- nfnetlink_queue.c, xt_TCPMSS.c, xt_TPROXY.c, xt_addrtype.c.
- xt_connlimit.c, xt_hashlimit.c, xt_osf.c

Detailed calltrace can be found at:
http://marc.info/?l=netfilter-devel&m=149667610710350&w=2

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: helpers: remove data_len usage for inkernel helpers

No need to track this for inkernel helpers anymore as
NF_CT_HELPER_BUILD_BUG_ON checks do this now.

All inkernel helpers know what kind of structure they
stored in helper->data.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: helper: add build-time asserts for helper data size

add a 32 byte scratch area in the helper struct instead of relying
on variable sized helpers plus compile-time asserts to let us know
if 32 bytes aren't enough anymore.

Not having variable sized helpers will later allow to add BUILD_BUG_ON
for the total size of conntrack extensions -- the helper extension is
the only one that doesn't have a fixed size.

The (useless!) NF_CT_HELPER_BUILD_BUG_ON(0); are added so that in case
someone adds a new helper and copy-pastes from one that doesn't store
private data at least some indication that this macro should be used
somehow is there...

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_expect: Add nf_ct_remove_expect()

When remove one expect, it needs three statements. And there are
multiple duplicated codes in current code. So add one common function
nf_ct_remove_expect to consolidate this.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: fix wrong memory initialisation

In commit 82de0be6862cd ("netfilter: Add helper array
register/unregister functions"),
struct nf_conntrack_helper sip[MAX_PORTS][4] was changed to
sip[MAX_PORTS * 4], so the memory init should have been changed to
memset(&sip[4 * i], 0, 4 * sizeof(sip[i]));

But as the sip[] table is allocated in the BSS, it is already set to 0

Fixes: 82de0be6862cd ("netfilter: Add helper array register/unregister functions")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: Use mod_timer_pending()

timer_del() followed by timer_add() can be replaced by
mod_timer_pending().

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: extend request line validation

on SIP requests, so a fragmented TCP SIP packet from an allow header starting with
INVITE,NOTIFY,OPTIONS,REFER,REGISTER,UPDATE,SUBSCRIBE
Content-Length: 0

will not bet interpreted as an INVITE request. Also Request-URI must start with an alphabetic character.

Confirm with RFC 3261
Request-Line = Method SP Request-URI SP SIP-Version CRLF

Fixes: 30f33e6dee80 ("[NETFILTER]: nf_conntrack_sip: support method specific request/response handling")
Signed-off-by: Ulrich Weber <ulrich.weber@riverbed.com>
Acked-by: Marco Angaroni <marcoangaroni@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: allow tab character in SIP headers

Current parsing methods for SIP headers do not allow the presence of
tab characters between header name and header value. As a result Call-ID
SIP headers like the following are discarded by IPVS SIP persistence
engine:

"Call-ID\t: mycallid@abcde"
"Call-ID:\tmycallid@abcde"

In above examples Call-IDs are represented as strings in C language.
Obviously in real message we have byte "09" before/after colon (":").

Proposed fix is in nf_conntrack_sip module.
Function sip_skip_whitespace() should skip tabs in addition to spaces,
since in SIP grammar whitespace (WSP) corresponds to space or tab.

Below is an extract of relevant SIP ABNF syntax.

Call-ID = ( "Call-ID" / "i" ) HCOLON callid
callid = word [ "@" word ]

HCOLON = *( SP / HTAB ) ":" SWS
SWS = [LWS] ; sep whitespace
LWS = [*WSP CRLF] 1*WSP ; linear whitespace
WSP = SP / HTAB
word = 1*(alphanum / "-" / "." / "!" / "%" / "*" /
"_" / "+" / "`" / "'" / "~" /
"(" / ")" / "<" / ">" /
":" / "\" / DQUOTE /
"/" / "[" / "]" / "?" /
"{" / "}" )

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: correct allowed characters in Call-ID SIP header

Current parsing methods for SIP header Call-ID do not check correctly all
characters allowed by RFC 3261. In particular "," character is allowed
instead of "'" character. As a result Call-ID headers like the following
are discarded by IPVS SIP persistence engine.

Call-ID: -.!%*_+`'~()<>:\"/[]?{}

Above example is composed using all non-alphanumeric characters listed
in RFC 3261 for Call-ID header syntax.

Proposed fix is in nf_conntrack_sip module; function iswordc() checks this
range: (c >= '(' && c <= '/') which includes these characters: ()*+,-./
They are all allowed except ",". Instead "'" is not included in the list.

Below is an extract of relevant SIP ABNF syntax.

Call-ID = ( "Call-ID" / "i" ) HCOLON callid
callid = word [ "@" word ]

HCOLON = *( SP / HTAB ) ":" SWS
SWS = [LWS] ; sep whitespace
LWS = [*WSP CRLF] 1*WSP ; linear whitespace
WSP = SP / HTAB
word = 1*(alphanum / "-" / "." / "!" / "%" / "*" /
"_" / "+" / "`" / "'" / "~" /
"(" / ")" / "<" / ">" /
":" / "\" / DQUOTE /
"/" / "[" / "]" / "?" /
"{" / "}" )

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: correct parsing of continuation lines in SIP headers

Current parsing methods for SIP headers do not properly manage
continuation lines: in case of Call-ID header the first character of
Call-ID header value is truncated. As a result IPVS SIP persistence
engine hashes over a call-id that is not exactly the one present in
the originale message.

Example: "Call-ID: \r\n abcdeABCDE1234"
results in extracted call-id equal to "bcdeABCDE1234".

In above example Call-ID is represented as a string in C language.
Obviously in real message the first bytes after colon (":") are
"20 0d 0a 20".

Proposed fix is in nf_conntrack_sip module.
Since sip_follow_continuation() function walks past the leading
spaces or tabs of the continuation line, sip_skip_whitespace()
should simply return the ouput of sip_follow_continuation().
Otherwise another iteration of the for loop is done and dptr
is incremented by one pointing to the second character of the
first word in the header.

Below is an extract of relevant SIP ABNF syntax.

Call-ID = ( "Call-ID" / "i" ) HCOLON callid
callid = word [ "@" word ]

HCOLON = *( SP / HTAB ) ":" SWS
SWS = [LWS] ; sep whitespace
LWS = [*WSP CRLF] 1*WSP ; linear whitespace
WSP = SP / HTAB
word = 1*(alphanum / "-" / "." / "!" / "%" / "*" /
"_" / "+" / "`" / "'" / "~" /
"(" / ")" / "<" / ">" /
":" / "\" / DQUOTE /
"/" / "[" / "]" / "?" /
"{" / "}" )

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack_sip: CSeq 0 is a valid CSeq

Do not drop packet when CSeq is 0 as 0 is also a valid value for CSeq.

simple_strtoul() will return 0 either when all digits are 0
or if there are no digits at all. Therefore when simple_strtoul()
returns 0 we check if first character is digit 0 or not.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Add helper array register/unregister functions

Add nf_ct_helper_init(), nf_conntrack_helpers_register() and
nf_conntrack_helpers_unregister() functions to avoid repetitive
opencoded initialization in helpers.

This patch keeps an id parameter for nf_ct_helper_init() not to break
helper matching by name that has been inconsistently exposed to
userspace through ports, eg. ftp-2121, and through an incremental id,
eg. tftp-1.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_helper: Fix helper unregister count.

helpers should unregister the only registered ports.
but, helper cannot have correct registered ports value when
failed to register.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_helper: define pr_fmt()

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: replace strnicmp with strncasecmp

The kernel used to contain two functions for length-delimited,
case-insensitive string comparison, strnicmp with correct semantics and
a slightly buggy strncasecmp. The latter is the POSIX name, so strnicmp
was renamed to strncasecmp, and strnicmp made into a wrapper for the new
strncasecmp to avoid breaking existing users.

To allow the compat wrapper strnicmp to be removed at some point in the
future, and to avoid the extra indirection cost, do
s/strnicmp/strncasecmp/g.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

netfilter: conntrack: seperate expect locking from nf_conntrack_lock

Netfilter expectations are protected with the same lock as conntrack
entries (nf_conntrack_lock). This patch split out expectations locking
to use it's own lock (nf_conntrack_expect_lock).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: consolidate NAT hook functions

There are currently seven different NAT hooks used in both
nf_conntrack_sip and nf_nat_sip, each of the hooks is exported in
nf_conntrack_sip, then set from the nf_nat_sip NAT helper.

And because each of them is exported there is quite some overhead
introduced due of this.

By introducing nf_nat_sip_hooks I am able to reduce both text/data
somewhat. For nf_conntrack_sip e. g. I get

text data bss dec
old 15243 5256 32 20531
new 15010 5192 32 20234

Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: extend RCU read lock in set_expected_rtp_rtcp()

Currently set_expected_rtp_rtcp() in the SIP helper uses
rcu_dereference() two times to access two different NAT hook
functions. However, only the first one is protected by the RCU
reader lock, but the 2nd isn't. Fix it by extending the RCU
protected area.

This is more a cosmetic thing since we rely on all netfilter hooks
being rcu_read_lock()ed by nf_hook_slow() in many places anyways,
as Patrick McHardy clarified.

Signed-off-by: Holger Eitzenberger <holger.eitzenberger@sophos.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: don't drop packets with offsets pointing outside the packet

Some Cisco phones create huge messages that are spread over multiple packets.
After calculating the offset of the SIP body, it is validated to be within
the packet and the packet is dropped otherwise. This breaks operation of
these phones. Since connection tracking is supposed to be passive, just let
those packets pass unmodified and untracked.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

hlist: drop the node parameter from iterators

I'm not sure why, but the hlist for each entry iterators were conceived

list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

netfilter: nf_ct_helper: better logging for dropped packets

Connection tracking helpers have to drop packets under exceptional
situations. Currently, the user gets the following logging message
in case that happens:

nf_ct_%s: dropping packet ...

However, depending on the helper, there are different reasons why a
packet can be dropped.

This patch modifies the existing code to provide more specific
error message in the scope of each helper to help users to debug
the reason why the packet has been dropped, ie:

nf_ct_%s: dropping packet: reason ...

Thanks to Joe Perches for many formatting suggestions.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: support Cisco 7941/7945 IP phones

Most SIP devices use a source port of 5060/udp on SIP requests, so the
response automatically comes back to port 5060:

phone_ip:5060 -> proxy_ip:5060 REGISTER
proxy_ip:5060 -> phone_ip:5060 100 Trying

The newer Cisco IP phones, however, use a randomly chosen high source
port for the SIP request but expect the response on port 5060:

phone_ip:49173 -> proxy_ip:5060 REGISTER
proxy_ip:5060 -> phone_ip:5060 100 Trying

Standard Linux NAT, with or without nf_nat_sip, will send the reply back
to port 49173, not 5060:

phone_ip:49173 -> proxy_ip:5060 REGISTER
proxy_ip:5060 -> phone_ip:49173 100 Trying

But the phone is not listening on 49173, so it will never see the reply.

This patch modifies nf_*_sip to work around this quirk by extracting
the SIP response port from the Via: header, iff the source IP in the
packet header matches the source IP in the SIP request.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

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.

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: add protocol independent NAT core

Convert the IPv4 NAT implementation to a protocol independent core and
address family specific modules.

Signed-off-by: Patrick McHardy <kaber@trash.net>

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>

netfilter: nf_conntrack: restrict NAT helper invocation to IPv4

The NAT helpers currently only handle IPv4 packets correctly. Restrict
invocation of the helpers to IPv4 in preparation of IPv6 NAT.

Signed-off-by: Patrick McHardy <kaber@trash.net>

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>

netfilter: nf_ct_sip: fix helper name

Commit 3a8fc53a (netfilter: nf_ct_helper: allocate 16 bytes for the helper
and policy names) introduced a bug in the SIP helper, the helper name is
sprinted to the sip_names array instead of instead of into the helper
structure. This breaks the helper match and the /proc/net/nf_conntrack_expect
output.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

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.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_helper: allocate 16 bytes for the helper and policy names

This patch modifies the struct nf_conntrack_helper to allocate
the room for the helper name. The maximum length is 16 bytes
(this was already introduced in 2.6.24).

For the maximum length for expectation policy names, I have
also selected 16 bytes.

This patch is required by the follow-up patch to support
user-space connection tracking helpers.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: add more values to enum ip_conntrack_info

Following error is raised (and other similar ones) :

net/ipv4/netfilter/nf_nat_standalone.c: In function ‘nf_nat_fn’:
net/ipv4/netfilter/nf_nat_standalone.c:119:2: warning: case value ‘4’
not in enumerated type ‘enum ip_conntrack_info’

gcc barfs on adding two enum values and getting a not enumerated
result :

case IP_CT_RELATED+IP_CT_IS_REPLY:

Add missing enum values

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: David Miller <davem@davemloft.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_sip: fix SDP parsing in TCP SIP messages for some Cisco phones

Some Cisco phones do not place the Content-Length field at the end of the
SIP message. This is valid, due to a misunderstanding of the specification
the parser expects the SDP body to start directly after the Content-Length
field. Fix the parser to scan for \r\n\r\n to locate the beginning of the
SDP body.

Reported-by: Teresa Kang <teresa_kang@gemtek.com.tw>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_ct_sip: validate Content-Length in TCP SIP messages

Verify that the message length of a single SIP message, which is calculated
based on the Content-Length field contained in the SIP message, does not
exceed the packet boundaries.

Signed-off-by: Patrick McHardy <kaber@trash.net>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

netfilter: nf_conntrack_sip: Add callid parser

Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Julian Anastasov <ja@ssi.bg>

netfilter: nf_conntrack_sip: Allow ct_sip_get_header() to be called with a null ct argument

Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Julian Anastasov <ja@ssi.bg>

netfilter: nf_ct_sip: default to NF_ACCEPT in sip_help_tcp()

I initially noticed this because of the compiler warning below, but it
does seem to be a valid concern in the case where ct_sip_get_header()
returns 0 in the first iteration of the while loop.

net/netfilter/nf_conntrack_sip.c: In function 'sip_help_tcp':
net/netfilter/nf_conntrack_sip.c:1379: warning: 'ret' may be used uninitialized in this function

Signed-off-by: Simon Horman <horms@verge.net.au>
[Patrick: changed NF_DROP to NF_ACCEPT]
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_ct_sip: handle non-linear skbs

Handle non-linear skbs by linearizing them instead of silently failing.
Long term the helper should be fixed to either work with non-linear skbs
directly by using the string search API or work on a copy of the data.

Based on patch by Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: cleanup printk messages

Make sure all printk messages have a severity level.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack: add support for "conntrack zones"

Normally, each connection needs a unique identity. Conntrack zones allow
to specify a numerical zone using the CT target, connections in different
zones can use the same identity.

Example:

iptables -t raw -A PREROUTING -i veth0 -j CT --zone 1
iptables -t raw -A OUTPUT -o veth1 -j CT --zone 1

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_sip: add T.38 FAX support

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_nat_sip: add TCP support

Add support for mangling TCP SIP packets.

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_sip: add TCP support

Add TCP support, which is mandated by RFC3261 for all SIP elements.

SIP over TCP is similar to UDP, except that messages are delimited
by Content-Length: headers and multiple messages may appear in one
packet.

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_sip: pass data offset to NAT functions

When using TCP multiple SIP messages might be present in a single packet.
A following patch will parse them by setting the dptr to the beginning of
each message. The NAT helper needs to reload the dptr value after mangling
the packet however, so it needs to know the offset of the message to the
beginning of the packet.

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_sip: fix ct_sip_parse_request() REGISTER request parsing

When requests are parsed, the "sip:" part of the SIP URI should be skipped.

Usually this doesn't matter because address parsing skips forward until after
the username part, but in case REGISTER requests it doesn't contain a username
and the address can not be parsed.

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack: show helper and class in /proc/net/nf_conntrack_expect

Make the output a bit more informative by showing the helper an expectation
belongs to and the expectation class.

Signed-off-by: Patrick McHardy <kaber@trash.net>

tree-wide: Assorted spelling fixes

In particular, several occurances of funny versions of 'success',
'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address',
'beginning', 'desirable', 'separate' and 'necessary' are fixed.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

netfilter: nf_conntrack_sip: fix off-by-one in compact header parsing

In a string like "v:SIP/2.0..." it was checking for !isalpha('S') when it
meant to be inspecting the ':'.

Patch by Greg Alexander <greqcs@galexander.org>

Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack: connection tracking helper name persistent aliases

This patch adds the macro MODULE_ALIAS_NFCT_HELPER that defines a
way to provide generic and persistent aliases for the connection
tracking helpers.

This next patch requires this patch.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: netns nf_conntrack: SIP conntracking in netns

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: netns nf_conntrack: per-netns expectations

Make per-netns a) expectation hash and b) expectations count.

Expectations always belongs to netns to which it's master conntrack belong.
This is natural and doesn't bloat expectation.

Proc files and leaf users are stubbed to init_net, this is temporary.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_sip: de-static helper pointers

Helper's ->help hook can run concurrently with itself, so iterating over
SIP helpers with static pointer won't work reliably.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_conntrack_sip: restrict RTP expect flushing on error to last request

Some Inovaphone PBXs exhibit very stange behaviour: when dialing for
example "123", the device sends INVITE requests for "1", "12" and
"123" back to back. The first requests will elicit error responses
from the receiver, causing the SIP helper to flush the RTP
expectations even though we might still see a positive response.

Note the sequence number of the last INVITE request that contained a
media description and only flush the expectations when receiving a
negative response for that sequence number.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: Fix SIP conntrack build with NAT disabled.

Reported by Ingo Molnar.

The SIP helper is also useful without NAT. This patch adds an ifdef
around the RTP call optimization for NATed clients.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack: add tuplehash l3num/protonum accessors

Add accessors for l3num and protonum and get rid of some overly long
expressions.

Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: nf_conntrack_sip: clear address in parse_addr()

Some callers pass uninitialized structures, clear the address to make
sure later comparisions work properly.

Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: nf_conntrack_sip: update copyright

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: RTP routing optimization

Optimize call routing between NATed endpoints: when an external
registrar sends a media description that contains an existing RTP
expectation from a different SNATed connection, the gatekeeper
is trying to route the call directly between the two endpoints.

We assume both endpoints can reach each other directly and
"un-NAT" the addresses, which makes the media stream go between
the two endpoints directly.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: support multiple media channels

Add support for multiple media channels and use it to create
expectations for video streams when present.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_nat_sip: split up SDP mangling

The SDP connection addresses may be contained in the payload multiple
times (in the session description and/or once per media description),
currently only the session description is properly updated. Split up
SDP mangling so the function setting up expectations only updates the
media port, update connection addresses from media descriptions while
parsing them and at the end update the session description when the
final addresses are known.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: create RTCP expectations

Create expectations for the RTCP connections in addition to RTP connections.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: allow media expectations with wildcard source address

Media streams can come from anywhere, add a module parameter which
controls whether wildcard expectations or expectations between the
two signalling endpoints are created.

Since the same media description sent on multiple connections may
results in multiple identical expections when using a wildcard source,
we need to check whether a similar expectation already exists for a
different connection before attempting to register it.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: create signalling expectations

Create expectations for incoming signalling connections when seeing
a REGISTER request. This is needed when the registrar uses a
different source port number for signalling messages and for receiving
incoming calls from other endpoints than the registrar.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: introduce URI and header parameter parsing helpers

Introduce URI and header parameter parsing helpers. These are needed
by the conntrack helper to parse expiration values in Contact: header
parameters and by the NAT helper to properly update the Via-header
rport=, received= and maddr= parameters.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: flush expectations on call termination

Flush the RTP expectations we've created when a call is hung up or
terminated otherwise.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: process ACK and PRACK methods

Both may contains SDP offers/answers.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: perform NAT after parsing

Perform NAT last after parsing the packet. This makes no difference
currently, but is needed when dealing with registrations to make
sure we seen the unNATed addresses.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: support method specific request/response handling

Add support for per-method request/response handlers and perform SDP
parsing for INVITE/UPDATE requests and for all informational and
successful responses.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: move SDP parsing to seperate function

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_nat_sip: get rid of text based header translation

Use the URI parsing helper to get the numerical addresses and get rid of the
text based header translation.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: introduce SIP-URI parsing helper

Introduce a helper function to parse a SIP-URI in a header value, optionally
iterating through all headers of this kind.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: parse SIP headers properly

Introduce new function for SIP header parsing that properly deals with
continuation lines and whitespace in headers and use it.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: kill request URI "header" definitions

The request URI is not a header and needs to be treated differently than
real SIP headers. Add a seperate function for parsing it and get rid of
the POS_REQ_URI/POS_REG_REQ_URI definitions.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: add seperate SDP header parsing function

SDP and SIP headers are quite different, SIP can have continuation lines,
leading and trailing whitespace after the colon and is mostly case-insensitive
while SDP headers always begin on a new line and are followed by an equal
sign and the value, without any whitespace.

Introduce new SDP header parsing function and convert all users that used
the SIP header parsing function. This will allow to properly deal with the
special SIP cases in the SIP header parsing function later.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: use strlen/strcmp

Replace sizeof/memcmp by strlen/strcmp. Use case-insensitive comparison
for SIP methods and the SIP/2.0 string, as specified in RFC 3261.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: remove redundant function arguments

The conntrack reference and ctinfo can be derived from the packet.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: adjust dptr and datalen after packet mangling

After mangling the packet, the pointer to the data and the length of the data
portion may change and need to be adjusted.

Use double data pointers and a pointer to the length everywhere and add a
helper function to the NAT helper for performing the adjustments.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: fix some off-by-ones

"limit" marks the first character outside the bounds.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack: introduce expectation classes and policies

Introduce expectation classes and policies. An expectation class
is used to distinguish different types of expectations by the
same helper (for example audio/video/t.120). The expectation
policy is used to hold the maximum number of expectations and
the initial timeout for each class.

The individual classes are isolated from each other, which means
that for example an audio expectation will only evict other audio
expectations.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_{conntrack,nat}_sip: annotate SIP helper with const

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: conntrack: get rid of sparse warnings

Teach sparse about locking here, and fix signed/unsigned warnings.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Introduce nf_inet_address

A few netfilter modules provide their own union of IPv4 and IPv6
address storage. Will unify that in this patch series.

(1/4): Rename union nf_conntrack_address to union nf_inet_addr and
move it to x_tables.h.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Spelling fixes

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Replace sk_buff ** with sk_buff *

With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: fix SIP-URI parsing

The userinfo component of a SIP-URI is optional, continue parsing at the
beginning of the SIP-URI in case its not found.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: check sname != NULL before calling strncmp

The check got lost during the conversion to nf_conntrack.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Convert DEBUGP to pr_debug

Convert DEBUGP to pr_debug and fix lots of non-compiling debug statements.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack: reduce masks to a subset of tuples

Since conntrack currently allows to use masks for every bit of both
helper and expectation tuples, we can't hash them and have to keep
them on two global lists that are searched for every new connection.

This patch removes the never used ability to use masks for the
destination part of the expectation tuple and completely removes
masks from helpers since the only reasonable choice is a full
match on l3num, protonum and src.u.all.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_expect: function naming unification

Currently there is a wild mix of nf_conntrack_expect_, nf_ct_exp_,
expect_, exp_, ...

Consistently use nf_ct_ as prefix for exported functions.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack_sip: add missing message types containing RTP info

Signed-off-by: Jerome Borsboom <j.borsboom@erasmusmc.nl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: Fix whitespace errors

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: SIP conntrack: fix out of bounds memory access

When checking for an @-sign in skp_epaddr_len, make sure not to
run over the packet boundaries.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: SIP conntrack: fix skipping over user info in SIP headers

When trying to skip over the username in the Contact header, stop at the
end of the line if no @ is found to avoid mangling following headers.
We don't need to worry about continuation lines because we search inside
a SIP URI.

Fixes Netfilter Bugzilla #532.

Signed-off-by: Lars Immisch <lars@ibp.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack: fix header inclusions for helpers

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack/nf_nat: add SIP helper port

Add IPv4 and IPv6 capable nf_conntrack port of the SIP conntrack/NAT helper.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>