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dhcpcd-7.0.0-rc3 has been released with the following noteable changes:

  • Fixed handling RA's from multiple routers
  • Fixed changing to a better route based on gateway
  • IPv6 default route is now deleted when config is not persistent
  • Use hmac(3) if available in libc to reduce binary size

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Here's the changelog:

  • dhcp: fixed classless static routes
  • prefix delegation: build routes after assigning addresses
  • dhcp: on lease expiration, discover only when carrier
  • ip6: fix potential segfault when lifetime overflows
  • bsd: compile on recent OpenBSD platforms
  • dhcp: fix reporting of DNS encoded SIP servers
  • dhcp6: fix unicast in non master mode

All the critical issues people have highighted have now been resolved, so hopefully this is the last rc before release :)

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So one of the main features of dhcpcd was the ability to add and remove addresses and subnets in accordance with interface preference and state. This worked very well in Linux, both for IPv4 and IPv6.

When I discovered FreeBSD and then NetBSD making dhcpcd work with the same features provided troublesome. For the IPv4 case, we needed to patch the kernel so that IFA_ROUTE remained sane. For the IPv6 case it was a lot more complicated as parts of the IPv6 stack rely on the kernel processing Router Advertisements instead of a 3rd party tool. Working this out was a lot more time consuming and complicated, but we got there with minimal fuss!

So as of now, dhcpcd can fully replace the NetBSD and Linux in kernel Router Advertisement handling code.

But why was I right after all these years? Because quite a few knowledgeable NetBSD folk assured me that the kernel was fine and it was likely dhcpcd at fault. As it turned out, it really was the kernels fault.

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It's been an eventful two years of not blogging. Mainly as I got heavily involved in playing World of Warcrat, Star Wars: The Old Republic and now Guild Wars 2 and this is a technical blog not a gaming one.

Anyhoo, since GW2 is a lot more casual than the others the idea is that I have more time for working on open source stuff, like say dhcpcd. Well, I finally found some time over the past few months and put DHCPv6 INFORM support into dhcpcd. This is only triggered when dhcpcd recieves an IPv6 RA with the O flag set. Luckily, I put IPv6 RS support into dhcpcd a few months ago but didn't feel the urge to blog about it. Well, I do now!

Before the end of the year, I aim to have DHCPv6 IA support triggered via IPv6 RA with the M flag set as well. Do I have any other goals? Well, all my other projects are pretty much complete. One of the reasons why I starting gaming so much is that I'm pretty happy with the current state of affairs and anything else is just a bonus. That being said, there are a lot more DHCPv6 things to do besides IA support such as better separation between IPv4 and IPv6, moving to TAILQ lists intsead of our hand rolled and other misc stuff such as improving dhcpcd-dbus and dhcpcd-gtk.

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dhcpcd-5.1.2 has been released with the following changes:

  • ClientID is now reported when interface starts
  • -w, --wait forces dhcpcd to wait until an interface gets a lease or times out
  • 50-ypbind hook added for BSD style NIS
  • Ensure DHCP socket is open when sending a DECLINE
  • Uses new hwaddr if existing interface is downed and then changed.
  • No longer works on firewire interfaces by default.

dhcpcd-5.1.2 has a new behaviour change - when starting up and at least 1 interface has a carrier then it tries to get a lease or times out. It still daemonises regardless. This, along with the -b and -w flags allows total control over the desired behaviour of dhcpcd.

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