hmm, on second thought, I think I would prefer the attached patch
(compiled but not tested).
Hardware usually returns all 1's when it's not present, or not working,
so think checking for addresses filled with 1's is a good idea too.
I also took the patch from alan's tree and made the memcmp against
six-byte 'zaddr' rather than a seven-byte string :)
-- Jeff Garzik | May you have warm words on a cold evening, Building 1024 | a full mooon on a dark night, MandrakeSoft | and a smooth road all the way to your door.
Index: include/linux/etherdevice.h =================================================================== RCS file: /cvsroot/gkernel/linux_2_4/include/linux/etherdevice.h,v retrieving revision 1.1.1.14.4.2 diff -u -r1.1.1.14.4.2 etherdevice.h --- include/linux/etherdevice.h 2001/03/21 14:10:50 1.1.1.14.4.2 +++ include/linux/etherdevice.h 2001/03/22 13:37:15 @@ -46,6 +46,25 @@ memcpy (dest->data, src, len); } +/** + * is_valid_ether_addr - Determine if the given Ethernet address is valid + * @addr: Pointer to a six-byte array containing the Ethernet address + * + * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not + * a multicast address, and is not FF:FF:FF:FF:FF:FF. + * + * Return true if the address is valid. + */ +static inline int is_valid_ether_addr( u8 *addr ) +{ + const char zaddr[6] = {0,}; + const char faddr[6] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF}; + + return !(addr[0]&1) && + memcmp( addr, zaddr, 6) && + memcmp( addr, faddr, 6); +} + #endif #endif /* _LINUX_ETHERDEVICE_H */
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This archive was generated by hypermail 2b29 : Fri Mar 23 2001 - 21:00:17 EST