Commit Graph

19 Commits

Author SHA1 Message Date
Jeremy Kerr
cb196b7259 mctp: replace mctp_address_ok with more fine-grained helpers
Currently, we have mctp_address_ok(), which checks if an EID is in the
"valid" range of 8-254 inclusive. However, 0 and 255 may also be valid
addresses, depending on context. 0 is the NULL EID, which may be set
when physical addressing is used. 255 is valid as a destination address
for broadcasts.

This change renames mctp_address_ok to mctp_address_unicast, and adds
similar helpers for broadcast and null EIDs, which will be used in an
upcoming commit.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-18 21:24:28 -08:00
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
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
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
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
David S. Miller
bdfa75ad70 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Lots of simnple overlapping additions.

With a build fix from Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-22 11:41:16 +01:00
Jeremy Kerr
b416beb25d mctp: unify sockaddr_mctp types
Use the more precise __kernel_sa_family_t for smctp_family, to match
struct sockaddr.

Also, use an unsigned int for the network member; negative networks
don't make much sense. We're already using unsigned for mctp_dev and
mctp_skb_cb, but need to change mctp_sock to suit.

Fixes: 60fc639816 ("mctp: Add sockaddr_mctp to uapi")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Acked-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 13:47:09 +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
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
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
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
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
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
2c8e2e9aec mctp: Add base packet definitions
Simple packet header format as defined by DMTF DSP0236.

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