Commit Graph

109 Commits

Author SHA1 Message Date
Jakub Kicinski
6b5567b1b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 11:44:20 -08:00
Tom Rix
7e5b6a5c8c mctp: fix use after free
Clang static analysis reports this problem
route.c:425:4: warning: Use of memory after it is freed
  trace_mctp_key_acquire(key);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
When mctp_key_add() fails, key is freed but then is later
used in trace_mctp_key_acquire().  Add an else statement
to use the key only when mctp_key_add() is successful.

Fixes: 4f9e1ba6de ("mctp: Add tracepoints for tag/key handling")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-15 14:54:40 +00:00
Matt Johnston
63ed1aab3d mctp: Add SIOCMCTP{ALLOC,DROP}TAG ioctls for tag control
This change adds a couple of new ioctls for mctp sockets:
SIOCMCTPALLOCTAG and SIOCMCTPDROPTAG.  These ioctls provide facilities
for explicit allocation / release of tags, overriding the automatic
allocate-on-send/release-on-reply and timeout behaviours. This allows
userspace more control over messages that may not fit a simple
request/response model.

In order to indicate a pre-allocated tag to the sendmsg() syscall, we
introduce a new flag to the struct sockaddr_mctp.smctp_tag value:
MCTP_TAG_PREALLOC.

Additional changes from Jeremy Kerr <jk@codeconstruct.com.au>.

Contains a fix that was:
Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 12:00:11 +00:00
Jeremy Kerr
0de55a7d11 mctp: Allow keys matching any local address
Currently, we require an exact match on an incoming packet's dest
address, and the key's local_addr field.

In a future change, we may want to set up a key before packets are
routed, meaning we have no local address to match on.

This change allows key lookups to match on local_addr = MCTP_ADDR_ANY.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 12:00:11 +00:00
Jeremy Kerr
8069b22d65 mctp: Add helper for address match checking
Currently, we have a couple of paths that check that an EID matches, or
the match value is MCTP_ADDR_ANY.

Rather than open coding this, add a little helper.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 12:00:11 +00:00
Jeremy Kerr
c575521462 mctp: tests: Add key state tests
This change adds a few more tests to check the key/tag lookups on route
input. We add a specific entry to the keys lists, route a packet with
specific header values, and check for key match/mismatch.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 12:00:11 +00:00
Jeremy Kerr
62a2b005c6 mctp: tests: Rename FL_T macro to FL_TO
This is a definition for the tag-owner flag, which has TO as a standard
abbreviation. We'll want to add a helper for the actual tag value in a
future change.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 12:00:11 +00:00
Jakub Kicinski
c78b8b20e3 net: don't include ndisc.h from ipv6.h
Nothing in ipv6.h needs ndisc.h, drop it.

Link: https://lore.kernel.org/r/20220203043457.2222388-1-kuba@kernel.org
Acked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Link: https://lore.kernel.org/r/20220203231240.2297588-1-kuba@kernel.org
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-04 14:15:11 -08:00
Matt Johnston
284a4d94e8 mctp: test: zero out sockaddr
MCTP now requires that padding bytes are zero.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Fixes: 1e4b50f06d ("mctp: handle the struct sockaddr_mctp padding fields")
Link: https://lore.kernel.org/r/20220110021806.2343023-1-matt@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-11 20:26:36 -08:00
Jakub Kicinski
b9adba350a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-05 14:36:10 -08:00
Gagan Kumar
ae81de7378 mctp: Remove only static neighbour on RTM_DELNEIGH
Add neighbour source flag in mctp_neigh_remove(...) to allow removal of
only static neighbours.

This should be a no-op change and might be useful later when mctp can
have MCTP_NEIGH_DISCOVER neighbours.

Signed-off-by: Gagan Kumar <gagan1kumar.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-02 12:18:14 +00:00
Matt Johnston
dbcefdeb2a mctp: emit RTM_NEWADDR and RTM_DELADDR
Userspace can receive notification of MCTP address changes via
RTNLGRP_MCTP_IFADDR rtnetlink multicast group.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20211220023104.1965509-1-matt@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-20 18:40:48 -08:00
Jakub Kicinski
fc993be36f Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-02 11:44:56 -08:00
Xu Wang
d9e56d1839 mctp: Remove redundant if statements
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02 13:09:33 +00:00
Matt Johnston
76d001603c mctp: Don't let RTM_DELROUTE delete local routes
We need to test against the existing route type, not
the rtm_type in the netlink request.

Fixes: 83f0a0b728 ("mctp: Specify route types, require rtm_type in RTM_*ROUTE messages")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02 12:15:25 +00:00
Yang Yingliang
5cfe53cfeb mctp: remove unnecessary check before calling kfree_skb()
The skb will be checked inside kfree_skb(), so remove the
outside check.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20211130031243.768823-1-yangyingliang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-30 18:09:23 -08:00
Jeremy Kerr
d851956544 mctp: test: fix skb free in test device tx
In our test device, we're currently freeing skbs in the transmit path
with kfree(), rather than kfree_skb(). This change uses the correct
kfree_skb() instead.

Fixes: ded21b7229 ("mctp: Add test utils")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-29 13:00:09 +00:00
Jeremy Kerr
f6ef47e5bd mctp/test: Update refcount checking in route fragment tests
In 99ce45d5e, we moved a route refcount decrement from
mctp_do_fragment_route into the caller. This invalidates the assumption
that the route test makes about refcount behaviour, so the route tests
fail.

This change fixes the test case to suit the new refcount behaviour.

Fixes: 99ce45d5e7 ("mctp: Implement extended addressing")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-18 12:01:14 +00:00
Eugene Syromiatnikov
e9ea574ec1 mctp: handle the struct sockaddr_mctp_ext padding field
struct sockaddr_mctp_ext.__smctp_paddin0 has to be checked for being set
to zero, otherwise it cannot be utilised in the future.

Fixes: 99ce45d5e7 ("mctp: Implement extended addressing")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-04 19:17:48 -07:00
Eugene Syromiatnikov
1e4b50f06d mctp: handle the struct sockaddr_mctp padding fields
In order to have the padding fields actually usable in the future,
there have to be checks that user space doesn't supply non-zero garbage
there.  It is also worth setting these padding fields to zero, unless
it is known that they have been already zeroed.

Cc: stable@vger.kernel.org # v5.15
Fixes: 5a20dd46b8 ("mctp: Be explicit about struct sockaddr_mctp padding")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-04 19:17:34 -07:00
Jeremy Kerr
67737c4572 mctp: Pass flow data & flow release events to drivers
Now that we have an extension for MCTP data in skbs, populate the flow
when a key has been created for the packet, and add a device driver
operation to inform of flow destruction.

Includes a fix for a warning with test builds:
Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29 13:23:51 +01:00
Jeremy Kerr
78476d315e mctp: Add flow extension to skb
This change adds a new skb extension for MCTP, to represent a
request/response flow.

The intention is to use this in a later change to allow i2c controllers
to correctly configure a multiplexer over a flow.

Since we have a cleanup function in the core path (if an extension is
present), we'll need to make CONFIG_MCTP a bool, rather than a tristate.

Includes a fix for a build warning with clang:
Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29 13:23:51 +01:00
Jeremy Kerr
212c10c3c6 mctp: Return new key from mctp_alloc_local_tag
In a future change, we will want the key available for future use after
allocating a new tag. This change returns the key from
mctp_alloc_local_tag, rather than just key->tag.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29 13:23:50 +01:00
Jeremy Kerr
99ce45d5e7 mctp: Implement extended addressing
This change allows an extended address struct - struct sockaddr_mctp_ext
- to be passed to sendmsg/recvmsg. This allows userspace to specify
output ifindex and physical address information (for sendmsg) or receive
the input ifindex/physaddr for incoming messages (for recvmsg). This is
typically used by userspace for MCTP address discovery and assignment
operations.

The extended addressing facility is conditional on a new sockopt:
MCTP_OPT_ADDR_EXT; userspace must explicitly enable addressing before
the kernel will consume/populate the extended address data.

Includes a fix for an uninitialised var:
Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26 14:58:45 +01:00
Matt Johnston
0b93aed284 mctp: Avoid leak of mctp_sk_key
mctp_key_alloc() returns a key already referenced.

The mctp_route_input() path receives a packet for a bind socket and
allocates a key. It passes the key to mctp_key_add() which takes a
refcount and adds the key to lists. mctp_route_input() should then
release its own refcount when setting the key pointer to NULL.

In the mctp_alloc_local_tag() path (for mctp_local_output()) we
similarly need to unref the key before returning (mctp_reserve_tag()
takes a refcount and adds the key to lists).

Fixes: 73c618456d ("mctp: locking, lifetime and validity changes for sk_keys")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15 11:22:08 +01:00
Jeremy Kerr
1e5e9250d4 mctp: Add input reassembly tests
Add multi-packet route input tests, for message reassembly. These will
feed packets to be received by a bound socket, or dropped.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-03 14:35:41 +01:00
Jeremy Kerr
8892c04907 mctp: Add route input to socket tests
Add a few tests for single-packet route inputs, testing the
mctp_route_input function.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-03 14:35:41 +01:00
Jeremy Kerr
b504db408c mctp: Add packet rx tests
Add a few tests for the initial packet ingress through
mctp_pkttype_receive function; mainly packet header sanity checks. Full
input routing checks will be added as a separate change.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-03 14:35:41 +01:00
Jeremy Kerr
ded21b7229 mctp: Add test utils
Add a new object for shared test utilities

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-03 14:35:41 +01:00
Jeremy Kerr
161eba50e1 mctp: Add initial test structure and fragmentation test
This change adds the first kunit test for the mctp subsystem, and an
initial test for the fragmentation path.

We're adding tests under a new net/mctp/test/ directory.

Incorporates a fix for module configs:

Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-03 14:35:41 +01:00
David S. Miller
b022f8866e Revert "Merge branch 'mctp-kunit-tests'"
This reverts commit 4f42ad2011, reversing
changes made to ea2dd331bf.

These chanfges break the build when mctp is modular.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:59:33 +01:00
Jeremy Kerr
bbde430319 mctp: Add input reassembly tests
Add multi-packet route input tests, for message reassembly. These will
feed packets to be received by a bound socket, or dropped.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:19:01 +01:00
Jeremy Kerr
d04dcc2d67 mctp: Add route input to socket tests
Add a few tests for single-packet route inputs, testing the
mctp_route_input function.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:19:01 +01:00
Jeremy Kerr
925c01afb0 mctp: Add packet rx tests
Add a few tests for the initial packet ingress through
mctp_pkttype_receive function; mainly packet header sanity checks. Full
input routing checks will be added as a separate change.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:19:01 +01:00
Jeremy Kerr
077b6d52df mctp: Add test utils
Add a new object for shared test utilities

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:19:00 +01:00
Jeremy Kerr
8c02066b05 mctp: Add initial test structure and fragmentation test
This change adds the first kunit test for the mctp subsystem, and an
initial test for the fragmentation path.

We're adding tests under a new net/mctp/test/ directory.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:19:00 +01:00
Matt Johnston
7b1871af75 mctp: Warn if pointer is set for a wrong dev type
Should not occur but is a sanity check.

May help tracking down Trinity reported issue
https://lore.kernel.org/lkml/20210913030701.GA5926@xsang-OptiPlex-9020/

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:12 +01:00
Matt Johnston
6183569db8 mctp: Set route MTU via netlink
A route's RTAX_MTU can be set in nested RTAX_METRICS

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:12 +01:00
Jeremy Kerr
97f09abffc mctp: Do inits as a subsys_initcall
In a future change, we'll want to provide a registration call for
mctp-specific devices. This requires us to have the networks established
before device driver inits, so run the core init as a subsys_initcall.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Jeremy Kerr
4f9e1ba6de mctp: Add tracepoints for tag/key handling
The tag allocation, release and bind events are somewhat opaque outside
the kernel; this change adds a few tracepoints to assist in
instrumentation and debugging.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Jeremy Kerr
7b14e15ae6 mctp: Implement a timeout for tags
Currently, a MCTP (local-eid,remote-eid,tag) tuple is allocated to a
socket on send, and only expires when the socket is closed.

This change introduces a tag timeout, freeing the tuple after a fixed
expiry - currently six seconds. This is greater than (but close to) the
max response timeout in upper-layer bindings.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Jeremy Kerr
43f55f23f7 mctp: Add refcounts to mctp_dev
Currently, we tie the struct mctp_dev lifetime to the underlying struct
net_device, and hold/put that device as a proxy for a separate mctp_dev
refcount. This works because we're not holding any references to the
mctp_dev that are different from the netdev lifetime.

In a future change we'll break that assumption though, as we'll need to
hold mctp_dev references in a workqueue, which might live past the
netdev unregister notification.

In order to support that, this change introduces a refcount on the
mctp_dev, currently taken by the net_device->mctp_ptr reference, and
released on netdev unregister events. We can then use this for future
references that might outlast the net device.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Jeremy Kerr
73c618456d mctp: locking, lifetime and validity changes for sk_keys
We will want to invalidate sk_keys in a future change, which will
require a boolean flag to mark invalidated items in the socket & net
namespace lists. We'll also need to take a reference to keys, held over
non-atomic contexts, so we need a refcount on keys also.

This change adds a validity flag (currently always true) and refcount to
struct mctp_sk_key.  With a refcount on the keys, using RCU no longer
makes much sense; we have exact indications on the lifetime of keys. So,
we also change the RCU list traversal to a locked implementation.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Jeremy Kerr
1f6c77ac9e mctp: Allow local delivery to the null EID
We may need to receive packets addressed to the null EID (==0), but
addressed to us at the physical layer.

This change adds a lookup for local routes when we see a packet
addressed to EID 0, and a local phys address.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Matt Johnston
f364dd71d9 mctp: Allow MCTP on tun devices
Allowing TUN is useful for testing, to route packets to userspace or to
tunnel between machines.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Jeremy Kerr
581edcd0c8 mctp: perform route destruction under RCU read lock
The kernel test robot reports:

  [  843.509974][  T345] =============================
  [  843.524220][  T345] WARNING: suspicious RCU usage
  [  843.538791][  T345] 5.14.0-rc2-00606-g889b7da23abf #1 Not tainted
  [  843.553617][  T345] -----------------------------
  [  843.567412][  T345] net/mctp/route.c:310 RCU-list traversed in non-reader section!!

- we're missing the rcu read lock acquire around the destruction path.

This change adds the acquire/release - the path is already atomic, and
we're using the _rcu list iterators.

Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-08 11:29:16 +01:00
Jeremy Kerr
83f0a0b728 mctp: Specify route types, require rtm_type in RTM_*ROUTE messages
This change adds a 'type' attribute to routes, which can be parsed from
a RTM_NEWROUTE message. This will help to distinguish local vs. peer
routes in a future change.

This means userspace will need to set a correct rtm_type in RTM_NEWROUTE
and RTM_DELROUTE messages; we currently only accept RTN_UNICAST.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20210810023834.2231088-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-11 16:01:17 -07:00
Colin Ian King
df7ba0eb25 mctp: remove duplicated assignment of pointer hdr
The pointer hdr is being initialized and also re-assigned with the
same value from the call to function mctp_hdr. Static analysis reports
that the initializated value is unused. The second assignment is
duplicated and can be removed.

Addresses-Coverity: ("Unused value").
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05 10:56:01 +01:00
Matt Johnston
03f2bbc4ee mctp: Allow per-netns default networks
Currently we have a compile-time default network
(MCTP_INITIAL_DEFAULT_NET). This change introduces a default_net field
on the net namespace, allowing future configuration for new interfaces.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Matt Johnston
26ab3fcaf2 mctp: Add dest neighbour lladdr to route output
Now that we have a neighbour implementation, hook it up to the output
path to set the dest hardware address for outgoing packets.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
4a992bbd36 mctp: Implement message fragmentation & reassembly
This change implements MCTP fragmentation (based on route & device MTU),
and corresponding reassembly.

The MCTP specification only allows for fragmentation on the originating
message endpoint, and reassembly on the destination endpoint -
intermediate nodes do not need to reassemble/refragment.  Consequently,
we only fragment in the local transmit path, and reassemble
locally-bound packets. Messages are required to be in-order, so we
simply cancel reassembly on out-of-order or missing packets.

In the fragmentation path, we just break up the message into MTU-sized
fragments; the skb structure is a simple copy for now, which we can later
improve with a shared data implementation.

For reassembly, we keep track of incoming message fragments using the
existing tag infrastructure, allocating a key on the (src,dest,tag)
tuple, and reassembles matching fragments into a skb->frag_list.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
833ef3b91d mctp: Populate socket implementation
Start filling-out the socket syscalls: bind, sendmsg & recvmsg.

This requires an input route implementation, so we add to
mctp_route_input, allowing lookups on binds & message tags. This just
handles single-packet messages at present, we will add fragmentation in
a future change.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Matt Johnston
831119f887 mctp: Add neighbour netlink interface
This change adds the netlink interfaces for manipulating the MCTP
neighbour table.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Matt Johnston
4d8b931928 mctp: Add neighbour implementation
Add an initial neighbour table implementation, to be used in the route
output path.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Matt Johnston
06d2f4c583 mctp: Add netlink route management
This change adds RTM_GETROUTE, RTM_NEWROUTE & RTM_DELROUTE handlers,
allowing management of the MCTP route table.

Includes changes from Jeremy Kerr <jk@codeconstruct.com.au>.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
889b7da23a mctp: Add initial routing framework
Add a simple routing table, and a couple of route output handlers, and
the mctp packet_type & handler.

Includes changes from Matt Johnston <matt@codeconstruct.com.au>.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
583be982d9 mctp: Add device handling and netlink interface
This change adds the infrastructure for managing MCTP netdevices; we add
a pointer to the AF_MCTP-specific data to struct netdevice, and hook up
the rtnetlink operations for adding and removing addresses.

Includes changes from Matt Johnston <matt@codeconstruct.com.au>.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
8f601a1e4f mctp: Add base socket/protocol definitions
Add an empty socket implementation, plus initialisation/destruction
handlers.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:49 +01:00
Jeremy Kerr
bc49d8169a mctp: Add MCTP base
Add basic Kconfig, an initial (empty) af_mctp source object, and
{AF,PF}_MCTP definitions, and the required definitions for a new
protocol type.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:49 +01:00