Date: Tue, 19 Jan 2021 07:03:14 +0100
To: ~alpine/devel@lists.alpinelinux.org
Subject: Re: Proposed system change: Use dhcpcd as default DHCP client
From: =?UTF-8?Q?S=C3=B6ren?= Tempel <soeren@soeren-tempel.net>
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Ariadne Conill <ariadne@dereferenced.org> wrote:
> Hello,

Hi,

Thanks for bringing this up, I think IPv6 support in Alpine is generally
a very important issue.

> By focusing on the dhcpcd client as our preferred DHCP client, we can=20
> support dual-stack IPv4+IPv6 autoconfiguration out of the box.  This is=20=

> helpful for CPE and home router deployments, where an ISP provides DHCP=20=

> for IPv4 and DHCPv6-PD for prefix delegation, which is the most common=20=

> form of dual-stack deployment at the consumer ISP level.

=46rom my subjective experience I don't agree with this statement, at
least where I am living ISP-provided CPEs employ SLAAC for IPv6
autoconfiguration. I've been using uhcp for the last > 5 years and
never had to configure a DHCPv6 client for IPv6 connectivity.

> At present, users must install dhcpcd or ISC dhclient in order to support=
=20
> this configuration -- while this is not a huge burden for the user, the=20=

> future is trending towards network deployments which do not have IPv4=20
> service at all[0], which makes integrating a high quality DHCPv6 client=20=

> into our base system a strategic priority.

If you are forced to use DHCPv6 instead of SLAAC: Doesn't our busybox
package already provide udhcpc6, why would it be necessary to install
dhcpcd or ISC dhclient in this scenario?

> By using dhcpcd by default, Alpine will support IPv4-only networks, IPv4=20=

> and IPv6 dual-stack networks and IPv6-only networks in all possible=20
> auto-configuration scenarios.

Alpine already supports these scenarios as long as SLAAC is used.

> Finally, dhcpcd has the best security maintenance record of the DHCP=20
> clients we presently support: BusyBox udhcpc, ISC dhclient and dhcpcd.

Source on this? What do you mean by "security maintenance record"? I
would expect the dhcpcd codebase to more complex than the udhcpc
implementation, i.e. would expect it to have more security critical bugs
(it also has more features after all). After all, apart from security
simplicity also used to be an Alpine design goal ;)

Personally not convinced (yet?) that we really need dhcpcd in alpine-base.

Greetings,
S=C3=B6ren