Merge branch 'mctp-core-protocol-updates-minor-fixes-tests'

Jeremy Kerr says:

====================
MCTP core protocol updates, minor fixes & tests

This series implements some procotol improvements for AF_MCTP,
particularly for systems with multiple MCTP networks defined. For those,
we need to add the network ID to the tag lookups, which then suggests an
updated version of the tag allocate / drop ioctl to allow the net ID to
be specified there too.

The ioctl change affects uabi, so might warrant some extra attention.

There are also a couple of new kunit tests for multiple-net
configurations.

We have a fix for populating the flow data when fragmenting, and a
testcase for that too.

Of course, any queries/comments/etc., please let me know!
====================

Link: https://lore.kernel.org/r/cover.1708335994.git.jk@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

2 files changed, 36 insertions, 2 deletions

diff --git a/include/net/mctp.h b/include/net/mctp.h
index da86e106c91d..0dfae6f51a32 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -87,7 +87,7 @@ struct mctp_sock {
 };
 
 /* Key for matching incoming packets to sockets or reassembly contexts.
- * Packets are matched on (src,dest,tag).
+ * Packets are matched on (peer EID, local EID, tag).
  *
  * Lifetime / locking requirements:
  *
@@ -133,6 +133,7 @@ struct mctp_sock {
  *    - through an expiry timeout, on a per-socket timer
  */
 struct mctp_sk_key {
+	unsigned int	net;
 	mctp_eid_t	peer_addr;
 	mctp_eid_t	local_addr; /* MCTP_ADDR_ANY for local owned tags */
 	__u8		tag; /* incoming tag match; invert TO for local */
@@ -254,7 +255,8 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
 
 void mctp_key_unref(struct mctp_sk_key *key);
 struct mctp_sk_key *mctp_alloc_local_tag(struct mctp_sock *msk,
-					 mctp_eid_t daddr, mctp_eid_t saddr,
+					 unsigned int netid,
+					 mctp_eid_t local, mctp_eid_t peer,
 					 bool manual, u8 *tagp);
 
 /* routing <--> device interface */
diff --git a/include/uapi/linux/mctp.h b/include/uapi/linux/mctp.h
index 154ab56651f1..e1db65df9359 100644
--- a/include/uapi/linux/mctp.h
+++ b/include/uapi/linux/mctp.h
@@ -50,7 +50,14 @@ struct sockaddr_mctp_ext {
 
 #define SIOCMCTPALLOCTAG	(SIOCPROTOPRIVATE + 0)
 #define SIOCMCTPDROPTAG		(SIOCPROTOPRIVATE + 1)
+#define SIOCMCTPALLOCTAG2	(SIOCPROTOPRIVATE + 2)
+#define SIOCMCTPDROPTAG2	(SIOCPROTOPRIVATE + 3)
 
+/* Deprecated: use mctp_ioc_tag_ctl2 / TAG2 ioctls instead, which defines the
+ * MCTP network ID as part of the allocated tag. Using this assumes the default
+ * net ID for allocated tags, which may not give correct behaviour on system
+ * with multiple networks configured.
+ */
 struct mctp_ioc_tag_ctl {
 	mctp_eid_t	peer_addr;
 
@@ -65,4 +72,29 @@ struct mctp_ioc_tag_ctl {
 	__u16		flags;
 };
 
+struct mctp_ioc_tag_ctl2 {
+	/* Peer details: network ID, peer EID, local EID. All set by the
+	 * caller.
+	 *
+	 * Local EID must be MCTP_ADDR_NULL or MCTP_ADDR_ANY in current
+	 * kernels.
+	 */
+	unsigned int	net;
+	mctp_eid_t	peer_addr;
+	mctp_eid_t	local_addr;
+
+	/* Set by caller, but no flags defined currently. Must be 0 */
+	__u16		flags;
+
+	/* For SIOCMCTPALLOCTAG2: must be passed as zero, kernel will
+	 * populate with the allocated tag value. Returned tag value will
+	 * always have TO and PREALLOC set.
+	 *
+	 * For SIOCMCTPDROPTAG2: userspace provides tag value to drop, from
+	 * a prior SIOCMCTPALLOCTAG2 call (and so must have TO and PREALLOC set).
+	 */
+	__u8		tag;
+
+};
+
 #endif /* __UAPI_MCTP_H */