diff options
Diffstat (limited to 'net/net_rand.h')
| -rw-r--r-- | net/net_rand.h | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/net/net_rand.h b/net/net_rand.h index c98db64280..ba9d0642cf 100644 --- a/net/net_rand.h +++ b/net/net_rand.h @@ -9,18 +9,35 @@ #ifndef __NET_RAND_H__ #define __NET_RAND_H__ -#define RAND_MAX 0xffffffff +#include <common.h> /* - * Seed the random number generator using the eth0 MAC address + * Return a seed for the PRNG derived from the eth0 MAC address. */ -void srand_mac(void); +static inline unsigned int seed_mac(void) +{ + unsigned char enetaddr[6]; + unsigned int seed; + + /* get our mac */ + eth_getenv_enetaddr("ethaddr", enetaddr); + + seed = enetaddr[5]; + seed ^= enetaddr[4] << 8; + seed ^= enetaddr[3] << 16; + seed ^= enetaddr[2] << 24; + seed ^= enetaddr[1]; + seed ^= enetaddr[0] << 8; + + return seed; +} /* - * Get a random number (after seeding with MAC address) - * - * @return random number + * Seed the random number generator using the eth0 MAC address. */ -unsigned long rand(void); +static inline void srand_mac(void) +{ + srand(seed_mac()); +} #endif /* __NET_RAND_H__ */ |