Nmap Development mailing list archives
Re: [nmap-svn] r11551 - ncat (SO_DEBUG)
From: David Fifield <david () bamsoftware com>
Date: Fri, 2 Jan 2009 12:40:12 -0700
On Mon, Dec 29, 2008 at 10:00:08PM -0600, Kris Katterjohn wrote:
On 12/29/2008 09:20 PM, Fyodor wrote:On Mon, Dec 29, 2008 at 05:24:30PM -0800, commit-mailer () insecure org wrote:Author: kris Date: Mon Dec 29 17:24:30 2008 Log: Adding -D to enable socket debugging (SO_DEBUG)Hi Kris. Can you describe how this works and what you're using it for?When socket debugging is enabled using this socket option, detailed data is available through trpt (or sometimes dmesg) about packets sent and received (however Linux doesn't seem to make any real use of this). Honestly I'm not using it for anything at the moment, but it's offered in various other programs such as ping, socat and other nc incarnations. So on top of it having some importance to people since it's being offered in many similar programs, there's my deep, personal, often problematic desire to analyze things as much as possible :)
I was having bizarre problems that I tracked down to this change. Reverse DNS resolution and NSE gave me a bunch of Nsock errors. Here's from a -sL scan of scanme.nmap.org: Starting Nmap 4.76 ( http://nmap.org ) at 2009-01-02 12:36 MST NSOCK (0.3140s) msevent_new (IOD #0) (EID #8) NSOCK (0.3140s) UDP connection requested to 192.168.0.1:53 (IOD #1) EID 8 NSOCK (0.3140s) msevent_new (IOD #0) (EID #18) NSOCK (0.3140s) Read request from IOD #0 [192.168.0.1:53] (timeout: -1ms) EID 18 NSOCK (0.3140s) msevent_new (IOD #0) (EID #27) NSOCK (0.3140s) Write request for 43 bytes to IOD #0 EID 27 [192.168.0.1:53]: .............52.134.13.64.in-addr.arpa..... NSOCK (0.3150s) nsock_loop() started (timeout=500ms). 3 events pending NSOCK (0.3150s) wait_for_events NSOCK (0.3150s) Callback: CONNECT SUCCESS for EID 8 [192.168.0.1:53] NSOCK (0.3150s) msevent_delete (IOD #0) (EID #8) NSOCK (0.3150s) Callback: WRITE ERROR [Input/output error (5)] for EID 27 [192.168.0.1:53] NSOCK (0.3150s) msevent_delete (IOD #0) (EID #27) The problem went away after I ran "make clean". Try that if the same thing is happening to you. I don't know what caused in in the first place, maybe the change in the size of the msiod struct wasn't noticed by files that depended on it. David Fifield _______________________________________________ Sent through the nmap-dev mailing list http://cgi.insecure.org/mailman/listinfo/nmap-dev Archived at http://SecLists.Org
Current thread:
- Re: [nmap-svn] r11551 - ncat (SO_DEBUG) David Fifield (Jan 02)
- Re: [nmap-svn] r11551 - ncat (SO_DEBUG) Kris Katterjohn (Jan 02)
- <Possible follow-ups>
- Re: [nmap-svn] r11551 - ncat (SO_DEBUG) Fyodor (Jan 04)
- Re: [nmap-svn] r11551 - ncat (SO_DEBUG) Kris Katterjohn (Jan 06)
- Re: [nmap-svn] r11551 - ncat (SO_DEBUG) Fyodor (Jan 06)
- Re: [nmap-svn] r11551 - ncat (SO_DEBUG) Kris Katterjohn (Jan 06)