Universally administered and locally administered addresses are distinguished by setting the second-least-significant bit of the first octet of the address. Having a function to check and set this U/L bit from a function makes it nice for boards that want to generate their own mac address to ensure they are locally administered.
Unicast and multicast addresses are distinguised by setting the least-significant bit of the first octet of the address. Having a function to check and set this U/M bit from a function it nice to make a generated mac address a unicast address.
This patch introduces both these helper functions
Signed-off-by: Olliver Schinagl oliver@schinagl.nl --- include/net.h | 43 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 40 insertions(+), 3 deletions(-)
diff --git a/include/net.h b/include/net.h index ad2a8a3678..00677a0a89 100644 --- a/include/net.h +++ b/include/net.h @@ -767,6 +767,9 @@ static inline int is_zero_ethaddr(const u8 *addr) return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]); }
+/* IEEE802 Unicast/Multicast bit */ +#define IEEE802_UM_BIT 0x1 + /** * is_multicast_ethaddr - Determine if the Ethernet address is a multicast. * @addr: Pointer to a six-byte array containing the Ethernet address @@ -776,7 +779,41 @@ static inline int is_zero_ethaddr(const u8 *addr) */ static inline int is_multicast_ethaddr(const u8 *addr) { - return 0x01 & addr[0]; + return addr[0] & IEEE802_UM_BIT; +} + +/** + * set_unicast_ethaddr - Make the supplied Ethernet address an unicast. + * @addr: Pointer to a six-byte array containing the Ethernet address + */ +static inline void set_unicast_ethaddr(u8 *addr) +{ + addr[0] &= ~IEEE802_UM_BIT; +} + +/* IEEE802 Universal/Local administration bit */ +#define IEEE802_UL_BIT 0x02 + +/** + * is_local_ethaddr - Determine if the Ethernet address is a locally + * administered MAC address. + * @addr: Pointer to a six-byte array containing the Ethernet address + * + * Return true if the address is a locally administered address. + */ +static inline int is_local_ethaddr(const u8 *addr) +{ + return addr[0] & IEEE802_UL_BIT; +} + +/** + * set_local_ethaddr - Make the supplied Ethernet address a locally + * administered one. + * @addr: Pointer to a six-byte array containing the Ethernet address + */ +static inline void set_local_ethaddr(u8 *addr) +{ + addr[0] |= IEEE802_UL_BIT; }
/* @@ -822,8 +859,8 @@ static inline void net_random_ethaddr(uchar *addr) for (i = 0; i < ARP_HLEN; i++) addr[i] = rand_r(&seed);
- addr[0] &= 0xfe; /* clear multicast bit */ - addr[0] |= 0x02; /* set local assignment bit (IEEE802) */ + addr[0] &= ~IEEE802_UM_BIT; + set_local_ethaddr(addr); }
/* Convert an IP address to a string */