Your message dated Mon, 21 Dec 2009 04:00:46 +0100
with message-id <[email protected]>
and subject line Re: Bug#492478: UDP echo does not work on localhost
has caused the Debian Bug report #492478,
regarding UDP echo does not work on localhost
to be marked as done.
This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.
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--
492478: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=492478
Debian Bug Tracking System
Contact [email protected] with problems
--- Begin Message ---
Package: openbsd-inetd
Version: 0.20080125-1
Echo is enabled on my machine:
$ grep echo /etc/inetd.conf
echo stream tcp nowait root internal
echo dgram udp wait root internal
TCP echo works:
$ telnet localhost 7
Trying 127.0.0.1...
Connected to localhost.localdomain.
Escape character is '^]'.
foo
foo
^]
telnet> quit
Connection closed.
UDP echo doesn't work on localhost:
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on lo, link-type EN10MB (Ethernet), capture size 96 bytes
15:53:51.594483 IP 127.0.0.1.55073 > 127.0.0.1.7: UDP, length 4
15:53:56.086400 IP 127.0.0.1.55073 > 127.0.0.1.7: UDP, length 4
but it doesn work on a different address:
15:54:15.788903 IP 192.168.100.150.35378 > 192.168.100.150.7: UDP, length 4
15:54:15.789143 IP 192.168.100.150.7 > 192.168.100.150.35378: UDP, length 4
15:54:18.797852 IP 192.168.100.150.35378 > 192.168.100.150.7: UDP, length 4
15:54:18.797906 IP 192.168.100.150.7 > 192.168.100.150.35378: UDP, length 4
Both traces were done on the ``lo'' interface.
Thanks for listening,
Juliusz
--- End Message ---
--- Begin Message ---
On Jul 26, Juliusz Chroboczek <[email protected]> wrote:
> UDP echo doesn't work on localhost:
This is a feature, I suppose that echoing back to localhost untrusted
packets has security implications:
switch ((in.s_addr & 0xff000000) >> 24) {
case 0: case 127: case 255:
goto bad;
}
And again, the UDP small services should never be enabled.
--
ciao,
Marco
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