net_rand.h
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/*
* Copied from LiMon - BOOTP.
*
* Copyright 1994, 1995, 2000 Neil Russell.
* (See License)
* Copyright 2000 Paolo Scaffardi
*/
#ifndef __NET_RAND_H__
#define __NET_RAND_H__
#include <common.h>
/*
* Return a seed for the PRNG derived from the eth0 MAC address.
*/
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;
}
/*
* Seed the random number generator using the eth0 MAC address.
*/
static inline void srand_mac(void)
{
srand(seed_mac());
}
#endif /* __NET_RAND_H__ */