Comments on: iPhone DNS Servers

By: ocean

ocean — Fri, 11 Mar 2011 03:06:05 +0000

After upgraded to ios sdk 4.3, this does not work any more:(

By: Matt Galloway

Matt Galloway — Mon, 31 Jan 2011 09:18:17 +0000

@Steve – Thanks for those comments. I’ll take a look when I get a chance. I’ve not been using ares with ipv6 nameservers so haven’t had to worry about it before.

By: Steve

Steve — Sat, 29 Jan 2011 06:43:26 +0000

Thanks, this was very helpful!

Couple of comments:
1. With c-ares v1.7.4 the ares_addr field has a union for ipv4 and ipv6. So the inside of the loop now needs to be something like

channel->servers[i].addr.family = AF_INET;
memcpy(&channel->servers[i].addr.addr.addr4, &_res.nsaddr_list[i].sin_addr, sizeof(struct in_addr));

2. This doesn’t support nameservers which themselves are only accessible via IPv6 addresses. But the _res field doesn’t seem to support that either (as of iOS 4.2), so I don’t see what can be done about it for now.

By: Matt Galloway

Matt Galloway — Sun, 05 Dec 2010 17:23:39 +0000

@Anim – It’s up to you really. Probably easiest to compile ares and add it as a static library to link against, mainly because then you’re using the configure script from the ares project properly.

By: Anim

Anim — Sun, 05 Dec 2010 12:02:57 +0000

as i understand we need to add ares lib to the iphone project.
should i compile ares and then add it or just add the source files?
any good reference of how to use it inside the objective-c?

By: luke

luke — Sun, 28 Nov 2010 14:31:10 +0000

Nice work.Kudos

By: iPhone DNS « Under The Bridge

iPhone DNS « Under The Bridge — Tue, 17 Nov 2009 18:19:59 +0000

[...] there are people out there better informed and/or more tenacious than trolls; so here is a solution using resolv.h that some bright spark who stumbled across our begging on the dev forums came up with, which you [...]