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[PATCH] uml: don't roll my own random MAC generator
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Use the existing random_ether_addr() instead of cooking up my own
version.  Pointed out by Dave Hollis and Jason Lunz.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Jeff Dike authored and Linus Torvalds committed Sep 29, 2006
1 parent 3b89af7 commit fade5d5
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Showing 3 changed files with 1 addition and 34 deletions.
4 changes: 1 addition & 3 deletions arch/um/drivers/net_kern.c
Original file line number Diff line number Diff line change
Expand Up @@ -310,9 +310,7 @@ static void setup_etheraddr(char *str, unsigned char *addr)
return;

random:
addr[0] = 0xfe;
addr[1] = 0xfd;
random_mac(addr);
random_ether_addr(addr)
}

static DEFINE_SPINLOCK(devices_lock);
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29 changes: 0 additions & 29 deletions arch/um/drivers/net_user.c
Original file line number Diff line number Diff line change
Expand Up @@ -259,32 +259,3 @@ char *split_if_spec(char *str, ...)
va_end(ap);
return str;
}

void random_mac(unsigned char *addr)
{
struct timeval tv;
long n;
unsigned int seed;

gettimeofday(&tv, NULL);

/* Assume that 20 bits of microseconds and 12 bits of the pid are
* reasonably unpredictable.
*/
seed = tv.tv_usec | (os_getpid() << 20);
srandom(seed);

/* Don't care about endianness here - switching endianness
* just rearranges what are hopefully random numbers.
*
* Assume that RAND_MAX > 65536, so random is called twice and
* we use 16 bits of the result.
*/
n = random();
addr[2] = (n >> 8) & 255;
addr[3] = n % 255;

n = random();
addr[4] = (n >> 8) & 255;
addr[5] = n % 255;
}
2 changes: 0 additions & 2 deletions arch/um/include/net_user.h
Original file line number Diff line number Diff line change
Expand Up @@ -50,6 +50,4 @@ extern char *split_if_spec(char *str, ...);

extern int dev_netmask(void *d, void *m);

extern void random_mac(unsigned char *addr);

#endif

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