[krbdev.mit.edu #3307] Re: kdc sends udp replies from wrong addresses, does not listen on loopback interface

[Denis Vlasenko via RT]

On Sunday 18 December 2005 18:46, Denis Vlasenko wrote:
> I have a box which has no permanent IP addresses except those
> which are configured on loopback device. Something like
> ppp server with pile of serial lines and no ethernet at all.
> 
> On loopback there is usual 127.0.0.1/8 address configured
> and also 1.2.3.4/8 address which is a "server address"
> to use for ppp clients for DNS etc.
> 
> kdc cannot start on it if there is no active ppp interfaces.
> 
> If there are active ppp's, it starts, but don't reply from
> 1.2.3.4 because it has sockets bound to ppp ip address(es)
> only, which are dynamic.
> 
> I have a patch which remedies this using just one socket bound
> to 0.0.0.0 and recvmsg/IP_PKTINFO trick. Would it be revieved
> or maybe you have some fundamental reasons against it?

Patch which fixes this is in attachment. Please review.

recv_from_to() and send_to_from() are duplicated in it,
I hope someone with more experience with krb source code tree
will have an idea in which .c file to place them for general use.
--
vda