Re: [PATCH net-next] ipv6: don't generate link-local addr in random or privacy mode
From: Lorenzo Colitti <hidden>
Date: 2021-11-17 08:37:01
Also in:
linux-mediatek, lkml, netdev
On Wed, Nov 17, 2021 at 4:22 PM Rocco Yue [off-list ref] wrote:
Disabling the kernel's automatic link-local address generation doesn't mean that it violates RFC 4291, because an appropriate link-local addr can be added to the cellulal NIC through ioctl.
Well, it would mean that the kernel requires additional work from userspace to respect the RFC.
The method you mentioned can also solve the current problem, but it seems to introduce more logic: (1) set the cellular interface addr_gen_mode to RANDOM_LL_TOKEN or PRIVACY_LL_TOKEN; (2) set the cellular interface up; (3) disable ipv6 first;
I don't think you need to set the interface up to disable IPv6. Also I think that if the interface is down autoconf won't run so you don't actually need to do this.
(4) set token addr through netlink;
Can't 4 be the same as 3? The same netlink message can configure both the addr_gen_mode and the token, no? It seems to me that the following should work, and would be much simpler. 1. Bring the interface down. All addresses are deleted. 2. Send a netlink request to set addr_gen_mode RANDOM_LL_TOKEN or PRIVACY_LL_TOKEN and set the token. 3. Bring the interface up. Autoconf runs. The link-local address is generated from the token. An RS is sent. When the RA is received, the global address is generated using RFC 7217 or randomly. Cheers, Lorenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel