Hi Michael,
On Thu, May 31, 2012 at 1:12 PM, Michael Walle michael@walle.cc wrote:
Replace rand() with the functions from lib/. The link-local network code stores its own seed, derived from the MAC address. Thus making it independent from calls to srand() in other modules.
Signed-off-by: Michael Walle michael@walle.cc Cc: Joe Hershberger joe.hershberger@ni.com
include/configs/ETX094.h | 1 + include/configs/MERGERBOX.h | 1 + include/configs/MVBC_P.h | 1 + include/configs/MVBLM7.h | 1 + include/configs/MVSMR.h | 1 + include/configs/bfin_adi_common.h | 1 + include/configs/sacsng.h | 1 + net/Makefile | 2 - net/link_local.c | 7 ++-- net/net_rand.c | 68 ------------------------------------- net/net_rand.h | 32 +++++++++++++---- 11 files changed, 36 insertions(+), 80 deletions(-) delete mode 100644 net/net_rand.c
diff --git a/include/configs/ETX094.h b/include/configs/ETX094.h index c427093..aee9915 100644 --- a/include/configs/ETX094.h +++ b/include/configs/ETX094.h @@ -54,6 +54,7 @@
#define CONFIG_FLASH_16BIT /* for board with 16bit wide flash */ #undef SB_ETX094 /* only for SB-Board with 16MB SDRAM */ +#define CONFIG_RAND #define CONFIG_BOOTP_RANDOM_DELAY /* graceful BOOTP recovery mode */
It would be great if this could be implied instead of explicit... see below.
#define CONFIG_ETHADDR 08:00:06:00:00:00 diff --git a/net/Makefile b/net/Makefile index 5264687..e7764ce 100644 --- a/net/Makefile +++ b/net/Makefile @@ -34,8 +34,6 @@ COBJS-$(CONFIG_CMD_DNS) += dns.o COBJS-$(CONFIG_CMD_NET) += eth.o COBJS-$(CONFIG_CMD_LINK_LOCAL) += link_local.o COBJS-$(CONFIG_CMD_NET) += net.o -COBJS-$(CONFIG_BOOTP_RANDOM_DELAY) += net_rand.o -COBJS-$(CONFIG_CMD_LINK_LOCAL) += net_rand.o
In the Makefile for lib/, mimic the implementation that you are removing here. This way each user of CMD_LINK_LOCAL and BOOTP_RANDOM_DELAY aren't forced to also define RAND. You can still also keep CONFIG_RAND for cases like your board where all you want is RAND. Don't forget that you need to add a COBJS := $(sort $(COBJS-y)) to the Makefile like this one in case more than one of the options is enabled for the same board.
COBJS-$(CONFIG_CMD_NFS) += nfs.o COBJS-$(CONFIG_CMD_PING) += ping.o COBJS-$(CONFIG_CMD_RARP) += rarp.o diff --git a/net/net_rand.h b/net/net_rand.h index c98db64..62de375 100644 --- a/net/net_rand.h +++ b/net/net_rand.h @@ -9,18 +9,36 @@ #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 timer and 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 = get_timer(0);
Do not include the timer here. The seed should always start the same for a given MAC address.
- seed ^= enetaddr[5];
- seed ^= enetaddr[4] << 8;
- seed ^= enetaddr[3] << 16;
- seed ^= enetaddr[2] << 24;
- seed ^= enetaddr[1];
- seed ^= enetaddr[0] << 8;
- return seed;
+}
Thanks, -Joe