Nmap Development mailing list archives
Re: Nmap's nc version fails to correctly do IPv4 fallback
From: Quanah Gibson-Mount <quanah () zimbra com>
Date: Tue, 18 Nov 2014 17:29:17 -0800
--On November 18, 2014 at 7:14:15 PM -0600 Daniel Miller <bonsaiviking () gmail com> wrote:
Quanah, Thank you for bringing this up. We previously debated this issue and were on the brink of accepting a patch to implement this sort of fallback in December 2013 [1]. I'm not really sure what happened there, but I will look into it and see if we can get this implemented for the next release. As obvious workarounds, you can explicitly request IPv6 or IPv4 with the -6 or -4 options respectively or use explicit numeric addresses.
I appreciate the follow up. In general, having to specify -4 or -6 when virtually all linux systems have both ipv4 and ipv6 localhost defined makes scripting "nc" calls a major pain. Not everything (yet) has dual stack support, and even those things that do, are not necessarily designed to listen on both ipv4 and ipv6 by default due to legacy reasons. We basically hit this when adding support in Zimbra for RHEL7 (which RHEL changed to ship the nmap nc). All the other platforms we support use the OpenBSD nc, and thus this was never an issue before. ;)
Regards, Quanah -- Quanah Gibson-Mount Platform Architect Zimbra, Inc -------------------- Zimbra :: the leader in open source messaging and collaboration _______________________________________________ Sent through the dev mailing list http://nmap.org/mailman/listinfo/dev Archived at http://seclists.org/nmap-dev/
Current thread:
- Nmap's nc version fails to correctly do IPv4 fallback Quanah Gibson-Mount (Nov 18)
- Re: Nmap's nc version fails to correctly do IPv4 fallback Daniel Miller (Nov 18)
- Re: Nmap's nc version fails to correctly do IPv4 fallback Quanah Gibson-Mount (Nov 18)
- Re: Nmap's nc version fails to correctly do IPv4 fallback Fyodor (Nov 18)
- Re: Nmap's nc version fails to correctly do IPv4 fallback Daniel Miller (Nov 18)