@@ -117,6 +117,31 @@ int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr);
int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr);
void mctp_route_remove_dev(struct mctp_dev *mdev);
+/* neighbour definitions */
+enum mctp_neigh_source {
+ MCTP_NEIGH_STATIC,
+ MCTP_NEIGH_DISCOVER,
+};
+
+struct mctp_neigh {
+ struct mctp_dev *dev;
+ mctp_eid_t eid;
+ enum mctp_neigh_source source;
+
+ unsigned char ha[MAX_ADDR_LEN];
+
+ struct list_head list;
+ struct rcu_head rcu;
+};
+
+int mctp_neigh_init(void);
+void mctp_neigh_exit(void);
+
+// ret_hwaddr may be NULL, otherwise must have space for MAX_ADDR_LEN
+int mctp_neigh_lookup(struct mctp_dev *dev, mctp_eid_t eid,
+ void *ret_hwaddr);
+void mctp_neigh_remove_dev(struct mctp_dev *mdev);
+
int mctp_routes_init(void);
void mctp_routes_exit(void);
@@ -31,5 +31,6 @@ struct mctp_dev {
struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev);
struct mctp_dev *__mctp_dev_get(const struct net_device *dev);
+struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev);
#endif /* __NET_MCTPDEVICE_H */
@@ -11,6 +11,10 @@
struct netns_mctp {
/* Only updated under RTNL, entries freed via RCU */
struct list_head routes;
+
+ /* neighbour table */
+ struct mutex neigh_lock;
+ struct list_head neighbours;
};
#endif /* __NETNS_MCTP_H__ */
@@ -1,3 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_MCTP) += mctp.o
-mctp-objs := af_mctp.o device.o route.o
+mctp-objs := af_mctp.o device.o route.o neigh.o
@@ -161,6 +161,10 @@ static __init int mctp_init(void)
if (rc)
goto err_unreg_proto;
+ rc = mctp_neigh_init();
+ if (rc)
+ goto err_unreg_proto;
+
mctp_device_init();
return 0;
@@ -176,6 +180,7 @@ static __init int mctp_init(void)
static __exit void mctp_exit(void)
{
mctp_device_exit();
+ mctp_neigh_exit();
mctp_routes_exit();
proto_unregister(&mctp_proto);
sock_unregister(PF_MCTP);
@@ -342,6 +342,7 @@ static void mctp_unregister(struct net_device *dev)
RCU_INIT_POINTER(mdev->dev->mctp_ptr, NULL);
mctp_route_remove_dev(mdev);
+ mctp_neigh_remove_dev(mdev);
kfree(mdev->addrs);
mctp_dev_destroy(mdev);
new file mode 100644
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management Component Transport Protocol (MCTP) - routing
+ * implementation.
+ *
+ * This is currently based on a simple routing table, with no dst cache. The
+ * number of routes should stay fairly small, so the lookup cost is small.
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#include <linux/idr.h>
+#include <linux/mctp.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+
+#include <net/mctp.h>
+#include <net/mctpdevice.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+
+static int __always_unused mctp_neigh_add(struct mctp_dev *mdev, mctp_eid_t eid,
+ enum mctp_neigh_source source,
+ size_t lladdr_len, const void *lladdr)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh;
+ int rc;
+
+ mutex_lock(&net->mctp.neigh_lock);
+ if (mctp_neigh_lookup(mdev, eid, NULL) == 0) {
+ rc = -EEXIST;
+ goto out;
+ }
+
+ if (lladdr_len > sizeof(neigh->ha)) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ neigh = kzalloc(sizeof(*neigh), GFP_KERNEL);
+ if (!neigh) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ INIT_LIST_HEAD(&neigh->list);
+ neigh->dev = mdev;
+ dev_hold(neigh->dev->dev);
+ neigh->eid = eid;
+ neigh->source = source;
+ memcpy(neigh->ha, lladdr, lladdr_len);
+
+ list_add_rcu(&neigh->list, &net->mctp.neighbours);
+ rc = 0;
+out:
+ mutex_unlock(&net->mctp.neigh_lock);
+ return rc;
+}
+
+static void __mctp_neigh_free(struct rcu_head *rcu)
+{
+ struct mctp_neigh *neigh = container_of(rcu, struct mctp_neigh, rcu);
+
+ dev_put(neigh->dev->dev);
+ kfree(neigh);
+}
+
+/* Removes all neighbour entries referring to a device */
+void mctp_neigh_remove_dev(struct mctp_dev *mdev)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh, *tmp;
+
+ mutex_lock(&net->mctp.neigh_lock);
+ list_for_each_entry_safe(neigh, tmp, &net->mctp.neighbours, list) {
+ if (neigh->dev == mdev) {
+ list_del_rcu(&neigh->list);
+ /* TODO: immediate RTM_DELNEIGH */
+ call_rcu(&neigh->rcu, __mctp_neigh_free);
+ }
+ }
+
+ mutex_unlock(&net->mctp.neigh_lock);
+}
+
+int mctp_neigh_lookup(struct mctp_dev *mdev, mctp_eid_t eid, void *ret_hwaddr)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh;
+ int rc = -EHOSTUNREACH; // TODO: or ENOENT?
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(neigh, &net->mctp.neighbours, list) {
+ if (mdev == neigh->dev && eid == neigh->eid) {
+ if (ret_hwaddr)
+ memcpy(ret_hwaddr, neigh->ha,
+ sizeof(neigh->ha));
+ rc = 0;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return rc;
+}
+
+/* namespace registration */
+static int __net_init mctp_neigh_net_init(struct net *net)
+{
+ struct netns_mctp *ns = &net->mctp;
+
+ INIT_LIST_HEAD(&ns->neighbours);
+ return 0;
+}
+
+static void __net_exit mctp_neigh_net_exit(struct net *net)
+{
+ struct netns_mctp *ns = &net->mctp;
+ struct mctp_neigh *neigh;
+
+ list_for_each_entry(neigh, &ns->neighbours, list)
+ call_rcu(&neigh->rcu, __mctp_neigh_free);
+}
+
+/* net namespace implementation */
+
+static struct pernet_operations mctp_net_ops = {
+ .init = mctp_neigh_net_init,
+ .exit = mctp_neigh_net_exit,
+};
+
+int __init mctp_neigh_init(void)
+{
+ return register_pernet_subsys(&mctp_net_ops);
+}
+
+void __exit mctp_neigh_exit(void)
+{
+ unregister_pernet_subsys(&mctp_net_ops);
+}