sctp: create udp4 sock and add its encap_rcv

This patch is to add the functions to create/release udp4 sock,
and set the sock's encap_rcv to process the incoming udp encap
sctp packets. In sctp_udp_rcv(), as we can see, all we need to
do is fix the transport header for sctp_rcv(), then it would
implement the part of rfc6951#section-5.4:

"When an encapsulated packet is received, the UDP header is removed.
Then, the generic lookup is performed, as done by an SCTP stack
whenever a packet is received, to find the association for the
received SCTP packet"

Note that these functions will be called in the last patch of
this patchset when enabling this feature.

v1->v2:
- Add pr_err() when fails to create udp v4 sock.
v2->v3:
- Add 'select NET_UDP_TUNNEL' in sctp Kconfig.
v3->v4:
- No change.
v4->v5:
- Change to set udp_port to 0 by default.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

treewide: replace '---help---' in Kconfig files with 'help'

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

net: sctp: Fix spelling in Kconfig help

Change 'handeled' to 'handled' in the Kconfig help for SCTP.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sctp: whitespace fixes

Remove blank line at EOF and trailing whitespace.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: Remove debug SCTP probe module

Remove SCTP probe module since jprobe has been deprecated.
That function is now replaced by sctp/sctp_probe and
sctp/sctp_probe_path trace-events.
You can use it via ftrace or perftools.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: add the sctp_diag.c file

This one will implement all the interface of inet_diag, inet_diag_handler.
which includes sctp_diag_dump, sctp_diag_dump_one and sctp_diag_get_info.

It will work as a module, and register inet_diag_handler when loading.

v2->v3:
- fix the mistake in inet_assoc_attr_size().

- change inet_diag_msg_laddrs_fill() name to inet_diag_msg_sctpladdrs_fill.

- change inet_diag_msg_paddrs_fill() name to inet_diag_msg_sctpaddrs_fill.

- add inet_diag_msg_sctpinfo_fill() to make asoc/ep fill code clearer.

- add inet_diag_msg_sctpasoc_fill() to make asoc fill code clearer.

- merge inet_asoc_diag_fill() and inet_ep_diag_fill() to
inet_sctp_diag_fill().

- call sctp_diag_get_info() directly, instead by handler, cause the caller
is in the same file with it.

- call lock_sock in sctp_tsp_dump_one() to make sure we call get sctp info
safely.

- after lock_sock(sk), we should check sk != assoc->base.sk.

- change mem[SK_MEMINFO_WMEM_ALLOC] to asoc->sndbuf_used for asoc dump when
asoc->ep->sndbuf_policy is set. don't use INET_DIAG_MEMINFO attr any more.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: get rid of SCTP_DBG_TSNS entirely

After having reworked the debugging framework, Neil and Vlad agreed to
get rid of the leftover SCTP_DBG_TSNS code for a couple of reasons:

We can use systemtap scripts to investigate these things, we now have
pr_debug() helpers that make life easier, and if we really need anything
else besides those tools, we will be forced to come up with something
better than we have there. Therefore, get rid of this ifdef debugging
code entirely for now.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: rework debugging framework to use pr_debug and friends

We should get rid of all own SCTP debug printk macros and use the ones
that the kernel offers anyway instead. This makes the code more readable
and conform to the kernel code, and offers all the features of dynamic
debbuging that pr_debug() et al has, such as only turning on/off portions
of debug messages at runtime through debugfs. The runtime cost of having
CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing,
is negligible [1]. If kernel debugging is completly turned off, then these
statements will also compile into "empty" functions.

While we're at it, we also need to change the Kconfig option as it /now/
only refers to the ifdef'ed code portions in outqueue.c that enable further
debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code
was enabled with this Kconfig option and has now been removed, we
transform those code parts into WARNs resp. where appropriate BUG_ONs so
that those bugs can be more easily detected as probably not many people
have SCTP debugging permanently turned on.

To turn on all SCTP debugging, the following steps are needed:

# mount -t debugfs none /sys/kernel/debug
# echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control

This can be done more fine-grained on a per file, per line basis and others
as described in [2].

[1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf
[2] Documentation/dynamic-debug-howto.txt

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net, sctp: remove CONFIG_EXPERIMENTAL

This config item has not carried much meaning for a while now and is
almost always enabled by default. As agreed during the Linux kernel
summit, remove it.

Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sctp: remove depends on CONFIG_EXPERIMENTAL

The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Sridhar Samudrala <sri@us.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>

sctp: fix Kconfig bug in default cookie hmac selection

Commit 0d0863b02002 ("sctp: Change defaults on cookie hmac selection")
added a "choice" to the sctp Kconfig file. It introduced a bug which
led to an infinite loop when while running "make oldconfig".

The problem is that the wrong symbol was defined as the default value
for the choice. Using the correct value gets rid of the infinite loop.

Note: if CONFIG_SCTP_COOKIE_HMAC_SHA1=y was present in the input
config file, both that and CONFIG_SCTP_COOKIE_HMAC_MD5=y be present
in the generated config file.

Signed-off-by: Alex Elder <elder@inktank.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sctp: Change defaults on cookie hmac selection

Recently I posted commit 3c68198e75 which made selection of the cookie hmac
algorithm selectable. This is all well and good, but Linus noted that it
changes the default config:
http://marc.info/?l=linux-netdev&m=135536629004808&w=2

I've modified the sctp Kconfig file to reflect the recommended way of making
this choice, using the thermal driver example specified, and brought the
defaults back into line with the way they were prior to my origional patch

Also, on Linus' suggestion, re-adding ability to select default 'none' hmac
algorithm, so we don't needlessly bloat the kernel by forcing a non-none
default. This also led me to note that we won't honor the default none
condition properly because of how sctp_net_init is encoded. Fix that up as
well.

Tested by myself (allbeit fairly quickly). All configuration combinations seems
to work soundly.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: David Miller <davem@davemloft.net>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: linux-sctp@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Make hmac algorithm selection for cookie generation dynamic

Currently sctp allows for the optional use of md5 of sha1 hmac algorithms to
generate cookie values when establishing new connections via two build time
config options. Theres no real reason to make this a static selection. We can
add a sysctl that allows for the dynamic selection of these algorithms at run
time, with the default value determined by the corresponding crypto library
availability.
This comes in handy when, for example running a system in FIPS mode, where use
of md5 is disallowed, but SHA1 is permitted.

Note: This new sysctl has no corresponding socket option to select the cookie
hmac algorithm. I chose not to implement that intentionally, as RFC 6458
contains no option for this value, and I opted not to pollute the socket option
namespace.

Change notes:
v2)
* Updated subject to have the proper sctp prefix as per Dave M.
* Replaced deafult selection options with new options that allow
developers to explicitly select available hmac algs at build time
as per suggestion by Vlad Y.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: netdev@vger.kernel.org
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement sctp association probing module

This patch implement sctp association probing module, the module
will be called sctp_probe.

This module allows for capturing the changes to SCTP association
state in response to incoming packets. It is used for debugging
SCTP congestion control algorithms.

Usage:
$ modprobe sctp_probe [full=n] [port=n] [bufsize=n]
$ cat /proc/net/sctpprobe

The output format is:
TIME ASSOC LPORT RPORT MTU RWND UNACK <REMOTE-ADDR STATE CWND SSTHRESH INFLIGHT PARTIAL_BYTES_ACKED MTU> ...

The output will be like this:
9.226086 c4064c48 9000 8000 1500 53352 1 *192.168.0.19 1 4380 54784 1252 0 1500
9.287195 c4064c48 9000 8000 1500 45144 5 *192.168.0.19 1 5880 54784 6500 0 1500
9.289130 c4064c48 9000 8000 1500 42724 5 *192.168.0.19 1 7380 54784 6500 0 1500
9.620332 c4064c48 9000 8000 1500 48284 4 *192.168.0.19 1 8880 54784 5200 0 1500
......

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Don't abort initialization when CONFIG_PROC_FS=n

This puts CONFIG_PROC_FS defines around the proc init/exit functions
and also avoids compiling proc.c if procfs is not supported.
Also make SCTP_DBG_OBJCNT depend on procfs.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Use crc32c library for checksum calculations.

The crc32c library used an identical table and algorithm
as SCTP. Switch to using the library instead of carrying
our own table. Using crypto layer proved to have too
much overhead compared to using the library directly.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

SCTP: Fix build issues with SCTP AUTH.

SCTP-AUTH requires selection of CRYPTO, HMAC and SHA1 since
SHA1 is a MUST requirement for AUTH. We also support SHA256,
but that's optional, so fix the code to treat it as such.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

[SCTP]: Use menuconfig objects.

Use menuconfigs instead of menus, so the whole menu can be disabled at
once instead of going through all options.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!