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		| Errata Guide to Ettercap GUI : Through Trial, 
		Error & Experience | 
	
	
		| Author:
		Rishabh Dangwal  | 
	
	
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			Ettercap is one of the best sniffing tools available today, but when 
			it comes to using it on non-security-distro's on which it is not 
			pre-configured to use with like Fedora, you might land into some 
			problems like me. It all started on a sunny day when I actually 
			thought to try it on Fedora Linux.  | 
		
	
		 
		 
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			PS : I won't be covering ncurses as its quite easy & offers little 
			to no hassles in operations, gave me no errors in operation 
			strangely.   
			
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		| Anyways..I installed ettercap it by typing - 
			
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		[root@zion xero]#su  Password:  [root@zion xero]# yum install 
		ettercap  or  [root@zion xero]# yum install ettercap-gui  | 
	
	
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		( I actually had problems with this one..)    Yum resolved 
		dependencies & installed it, I ran it on my local lan network assuming 
		to run it on default configuration.  | 
	
	
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		[root@zion xero]# ettercap -T -Q -M ARP //192.168.1.3  It 
		successfully captured all the packets & I was able to get details about 
		capturing. The real problems started when I started to run it on GUI 
		mode.  [root@zion xero]# ettercap -G  | 
	
	
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		| On lauch, the gtk gui popped up & prompted me to the stuff. I quickly 
		pressed shift + U to choose network interface ( in this case my local 
		lan network hooked up to my roommates laptops ), & chose 'eth0' the 
		default Ethernet interface. I went ahead by scanning for hosts by 
		pressing "ctrl + s" & bam..it crashed. | 
	
	
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		ettercap NG-0.7.3 copyright 2001-2004 ALoR & NaGA  Ooops ! This 
		shouldn't happen... Segmentation Fault...  Please recompile in 
		debug mode, reproduce the bug and send a bugreport  | 
	
	
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		okay..I got it..it might need to be crashing cause it has not been 
		updated since a long time. Ah well, I compromised it by scanning 
		partially for hosts & then running it. Again, I chose the host, added it 
		to my target,mitm & started ARP poisoning (using the menu) & then 
		started with unified sniffing.  I got nothing.    Realizing it was 
		not backtrack, I sensibly closed it ( rearping the network..not by 
		deliberately closing it like windows users do by abusing the [X] button) 
		& opened etter.conf  | 
	
	
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		| [root@zion xero]# vi /etc/etter.conf  | 
	
	
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		| & uncommented the iptables option to look like this  | 
	
	
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		# if you use iptables:  redir_command_on = "iptables -t nat -A 
		PREROUTING -i %iface -p tcp --dport %port -j REDIRECT --to-port %rport"
		 redir_command_off = "iptables -t nat -D PREROUTING -i %iface -p tcp 
		--dport %port -j REDIRECT --to-port %rport"  | 
	
	
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		saved it, ran it again.    Again, the same drill, partial hosts 
		scanning,target selection,mitm,arping,sniffing.  bang, I got 
		nothing..again. 
  I looked at the console output & found -  | 
	
	
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		[root@zion xero]#  ettercap NG-0.7.3 copyright 2001-2004 ALoR & 
		NaGA  iptables v1.3.3: can't initialize iptables table `nat': 
		Permission denied (you must be root)  Perhaps iptables or your kernel 
		needs to be upgraded. | 
	
	
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		| wow..I am running the program as root , edited the read only file as 
		root & all i got was to upgrade my kernel ? bullshit! Anyways..back to 
		etter.conf , this time I changed the privileges to 0  | 
	
	
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		[privs]  ec_uid = 0 # nobody is the default  ec_gid = 0 # 
		nobody is the default  | 
	
	
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		The program ran & the error went away :)    but still..i was unable 
		to capture anything in the GUI mode, guess the more user friendly you 
		make it, the more hassles you add with it...sheesh. I was into new stuff 
		like after 10 minutes of waiting I got this -  | 
	
	
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		| SEND L3 ERROR: 44 byte packet (0800:06) destined to 192.168.xxx.xxx 
		was not forwarded (libnet_write_raw_ipv4(): -1 bytes written (Operation 
		not permitted)  | 
	
	
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		Great...now this was what I was talking about. Now this really got 
		me moving. Its not like every day when you can target a network in CUI 
		using one command of a program but using a GUI has a lot of strings 
		attached.    Now I did everything very carefully, although I was still 
		not able to figure out the real reason of "Segmentation Fault problem" , 
		but I guess everything works fine if you do it like this – 
  
		Configure etter.conf like I stated above, set uid to 0 & uncomment 
		iptables section.
  run ettercap using kdesu, yep ran it with elevated 
		privileges in kde environment to avoid "cant initialize iptables error". | 
	
	
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		| [root@zion xero]# kdesu ettercap -G  | 
	
	
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		give your password , & choose network interface (shift + U).  
		Once done, please be patient, open a new terminal window, change to root 
		& type this command (forwards packets, avoids error :P ) -  | 
	
	
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		| [root@zion xero]# echo "1" > /proc/sys/net/ipv4/ip_forward  | 
	
	
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		| it will avoid the "SEND L3 ERROR" .  | 
	
	
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		| Once done, do your drill & you 
		will be "finally" able to capture data using GUI. For the rest of elites 
		out there, I guess  | 
	
	
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		| [root@zion xero]# ettercap -T -Q -M arp:remote -i eth0 /192.168.1.3/ 
		//  | 
	
	
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		| Seems to work :) man...What a trip... I would choose wireshark over 
		it any day... | 
	
	
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		 If you have ever got into problems while 
			trying to run Ettercap on your Linux box then this guide will help 
			you to get rid of some of those nasty errors and let you smooth sailing.
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