Nmap Development mailing list archives
Re: netcat missing example (is this even possible?)
From: David Fifield <david () bamsoftware com>
Date: Wed, 2 Jun 2010 10:38:13 -0600
On Wed, Jun 02, 2010 at 03:44:43PM +1000, David Burrows wrote:
Hi (response below), On Wed, Jun 2, 2010 at 9:43 AM, David Fifield <david () bamsoftware com> wrote:On Wed, Jun 02, 2010 at 03:42:53AM +1000, David Burrows wrote:Hello again! Sorry to reply to my own post so soon, but it appears that I have found a solution that could save someone the trouble of what I just went though. (on server) socat /dev/urandom TCP4-LISTEN:9999 (on client - substitute localhost for the servers ip if not localhost) socat TCP4:localhost:9999 PTY,link=/dev/newrandom,raw,echo=0 The server socat command can be substituted with: ncat -l -k 9999 -c 'cat /dev/urandom' I'm not sure if there would be a netcat equivalent of the clientconnection.Now you can "dd bs=nnn count=1 /dev/newrandom of=/dev/null" and cat, etcallworks as expected with the newly cloned device.Ncat doesn't have code to create a pty. You could probably do it with a fifo: $ ncat -l -k 9999 --sh-exec "cat /dev/urandom" $ mkfifo /dev/newrandom $ ncat localhost 9999 > /dev/newrandomOk this works as expected, except when a test dd process closes the /dev/newrandom fifo, the second ncat exits with the error "Broken pipe".
I see that too. I don't have a good solution for you, but as a dumb workaround you can use a SIGPIPE-ignoring Perl buffer like this. $ ncat localhost 9999 | perl -e 'use bytes;$SIG{PIPE}="IGNORE";while(sysread(STDIN,$_,1024)){syswrite(STDOUT,$_);}' > /dev/newrandom You might want to double-check that two processes reading from /dev/newrandom simultaneously will get different random bytes; I'm not sure that's the case. David Fifield _______________________________________________ Sent through the nmap-dev mailing list http://cgi.insecure.org/mailman/listinfo/nmap-dev Archived at http://seclists.org/nmap-dev/
Current thread:
- netcat missing example (is this even possible?) David Burrows (Jun 01)
- Re: netcat missing example (is this even possible?) David Burrows (Jun 01)
- Re: netcat missing example (is this even possible?) David Fifield (Jun 01)
- Re: netcat missing example (is this even possible?) David Burrows (Jun 01)
- Re: netcat missing example (is this even possible?) David Fifield (Jun 02)
- Re: netcat missing example (is this even possible?) David Burrows (Jun 03)
- Re: netcat missing example (is this even possible?) David Fifield (Jun 01)
- Re: netcat missing example (is this even possible?) David Burrows (Jun 01)