From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Westphal <fw@strlen.de>
Subject: Re: [PATCH next] netfilter: ipv6: add getsockopt to retrieve
 origdst
Date: Wed, 31 Oct 2012 09:48:15 +0100
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Cc: Florian Westphal <fw@strlen.de>,
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To: Nick Jones <nick.jones@network-box.com>
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Nick Jones <nick.jones@network-box.com> wrote:
> > getsockopt(m_sock, SOL_IP, SO_ORIGINAL_DST, &m_server_addr, &addrsize)
> > 
> > but for ipv6 no such option existed.
> > 
> > This adds getsockopt(..., IPPROTO_IPV6, IP6T_SO_ORIGINAL_DST, ...).
> > 
> > Without this, userspace needs to parse /proc or use ctnetlink, which
> > appears to be overkill.
> 
> Doesn't getsockname(2) provide this information?

No.  It will show the local address (the address we REDIRECT'ed to).

> It does for TPROXY'd connections.

Yes, because with TPROXY the destination won't be rewritten.