From e8013f8edaa30e17fd583a326daff1fa86b75c82 Mon Sep 17 00:00:00 2001 From: Casper Andersson Date: Thu, 25 Aug 2022 11:28:35 +0200 Subject: [PATCH] ethernet: Add helpers to recognize addresses mapped to IP multicast IP multicast must sometimes be discriminated from non-IP multicast, e.g. when determining the forwarding behavior of a given group in the presence of multicast router ports on an offloaded bridge. Therefore, provide helpers to identify these groups. Signed-off-by: Casper Andersson Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 92b10e67d5f8..a541f0c4f146 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -428,6 +428,28 @@ static inline bool ether_addr_equal_masked(const u8 *addr1, const u8 *addr2, return true; } +static inline bool ether_addr_is_ipv4_mcast(const u8 *addr) +{ + u8 base[ETH_ALEN] = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 }; + u8 mask[ETH_ALEN] = { 0xff, 0xff, 0xff, 0x80, 0x00, 0x00 }; + + return ether_addr_equal_masked(addr, base, mask); +} + +static inline bool ether_addr_is_ipv6_mcast(const u8 *addr) +{ + u8 base[ETH_ALEN] = { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 }; + u8 mask[ETH_ALEN] = { 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 }; + + return ether_addr_equal_masked(addr, base, mask); +} + +static inline bool ether_addr_is_ip_mcast(const u8 *addr) +{ + return ether_addr_is_ipv4_mcast(addr) || + ether_addr_is_ipv6_mcast(addr); +} + /** * ether_addr_to_u64 - Convert an Ethernet address into a u64 value. * @addr: Pointer to a six-byte array containing the Ethernet address