From a8a17fd22326f0d1aa7644556eea6010e0779afe Mon Sep 17 00:00:00 2001 From: David Bauer Date: Fri, 15 Jan 2021 02:15:12 +0100 Subject: [PATCH] rockchip: use stable MAC-address for NanoPi R2S The NanoPi R2S does not have a board specific MAC address written inside e.g. an EEPROM, hence why it is randomly generated on first boot. The issue with that however is the lack of a driver for the PRNG. It often results to the same MAC address used on multiple boards by default, as urngd is not active at this early stage resulting in low available entropy. There is however a semi-unique identifier available to us, which is the CID of the used SD card. It is unique to each SD card, hence we can use it to generate the MAC address used for LAN and WAN. Signed-off-by: David Bauer --- .../rockchip/armv8/base-files/etc/board.d/02_network | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/target/linux/rockchip/armv8/base-files/etc/board.d/02_network b/target/linux/rockchip/armv8/base-files/etc/board.d/02_network index e129fd6a670c..48133c81a164 100755 --- a/target/linux/rockchip/armv8/base-files/etc/board.d/02_network +++ b/target/linux/rockchip/armv8/base-files/etc/board.d/02_network @@ -17,6 +17,13 @@ rockchip_setup_interfaces() esac } +nanopi_r2s_generate_mac() +{ + local sd_hash=$(sha256sum /sys/devices/platform/ff500000.dwmmc/mmc_host/mmc0/mmc0:*/cid) + local mac_base=$(macaddr_canonicalize "$(echo "${sd_hash}" | dd bs=1 count=12 2>/dev/null)") + echo "$(macaddr_unsetbit_mc "$(macaddr_setbit_la "${mac_base}")")" +} + rockchip_setup_macs() { local board="$1" @@ -26,7 +33,7 @@ rockchip_setup_macs() case "$board" in friendlyarm,nanopi-r2s) - wan_mac=$(macaddr_random) + wan_mac=$(nanopi_r2s_generate_mac) lan_mac=$(macaddr_add "$wan_mac" +1) ;; esac -- 2.30.2