net/ethernet.h: Add make_ether_addr()lf/dev/make_ether_addr

This function turns an array of octets into a struct ether_addr,
which is useful when type-safe code (which uses ether_addr) wants
to interoperate with the many parts of the kernel where addresses
are stored as plain byte arrays.

To avoid sacrificing performance for safety, make the function
static inline.

1 files changed, 10 insertions, 1 deletions

diff --git a/sys/net/ethernet.h b/sys/net/ethernet.h
index 01485cf26e06..3c296852e3d6 100644
--- a/sys/net/ethernet.h
+++ b/sys/net/ethernet.h
@@ -447,6 +447,7 @@ void ether_bpf_mtap_if(struct ifnet *ifp, struct mbuf *m);
 #ifdef _KERNEL
 
 #include <sys/_eventhandler.h>
+#include <sys/systm.h>
 
 struct ifnet;
 struct mbuf;
@@ -479,10 +480,18 @@ void	ether_gen_addr_byname(const char *nameunit, struct ether_addr *hwaddr);
 
 static __inline struct mbuf *ether_vlanencap(struct mbuf *m, uint16_t tag)
 {
-
 	return ether_vlanencap_proto(m, tag, ETHERTYPE_VLAN);
 }
 
+/* Create an ether_addr from an array of u_char (or uint8_t). */
+__nodiscard static __inline __unused struct ether_addr
+make_ether_addr(const u_char *__octets)
+{
+	struct ether_addr __ret;
+	memcpy(&__ret.octet[0], __octets, ETHER_ADDR_LEN);
+	return (__ret);
+}
+
 /* new ethernet interface attached event */
 typedef void (*ether_ifattach_event_handler_t)(void *, struct ifnet *);
 EVENTHANDLER_DECLARE(ether_ifattach_event, ether_ifattach_event_handler_t);