Netcat ?'s

I was exploring about with netcat yesterday on windows and i was having some problems doing some of the stuff that i thought it should be able to do. for example, i set it up on 2 of my comps to give me cmd.exe when i connect to them. when i connect to them, i cant execute programs, if i run ie, it will start in the background but wont actually do anything. this makes it hard for me to use programs like shutdown or telnet(shouldnt i be able to telnet to my downstairs comp and from that be able to telnet to my other comp?). also, i tried putting nc in the windows directory and making a batch file like this(and put it in the startup folder so it runs everytime the comp is started):

Quote:

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@echo off
@nc -v -L -d -p 1 -e cmd.exe

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and it just hangs and never really starts netcat, i had to make a shortcut with a target of "C:\WINDOWS\nc.exe -v -L -d -p 1 -e cmd.exe". it does the same thing, but id really like to figure out why the batch file didnt work(im wierd like that:rolleyes:)

For chaining telnet sessions like your trying, you'll have to find a commandline telnet client, so you can use it on the command line. Windows 2k and XP come with this standard.

Not sure why it won't start right. It's a bad idea however you manage to do it. There's no security whatsoever. You should look into openssh and such. I don't know if they have a server for windows. Maybe you could work something out with cygwin.

im on a private network, behind a fw so its pretty secure. the telnet client ur talking about, is that the one in dos? i've been using that, it still doesnt work... for example:
i open the dos prompt, type "telnet downstairscomp 1", then im at the prompt for my downstairs comp, then i try to telnet to my 3rd comp, "telnet 3rdcomp 1", and nothing actually happens, it accepts the command but its not like i get connected to the next computer in a chain like i wanted. i think whats happening is the downstairs computer runs telnet downstairs, but as a background process. i want to be able to access it from my upstairs computer though. why do all the programs i try to run remotely with netcat open as background processes?

make sure that their not both bound to the same port you cant lnk from one too another if its bound to the same port

as for your batch file makesure that dos can see netcat without being directed to it and you dont need that @ before nc when echo is off

getting rid of the @ fixed it, but the prompt window that opens from it never closes for some reason... so netcat runs but i have to physically close the cmd window thats opened up from the .bat file even if i use a -d in order to make nc run in the background and put an "exit" at the end of the batch file.

they arent bound to the same port, i have nc running on 3 comps, what i want to do is telnet from comp A to comp B, get a command prompt at comp B and then run telnet again to comp C.

like this:
comp A(where i am)---> comp B ---> comp C

the problem is that i go to comp b(via telnet) then try to telnet to comp C and it echoes my command and telnet starts running on computer B(as a background process), but i cant give commands to it from comp A, its kind of hard for me to explain

for the batch file if you write start /B nc -d -e cmd.exe -p 23 -L that should take care of it

1) no win95 with nc
2) get it working without batch files first
3) don't run any gui progs
4) two methods to make a nc relays are:
A) nc -l -p 11111 | nc next_hop 54321 | nc previous_hop 22222
b)nc -l -p 11111 0<backpipe | nc next_hop 54321 1>backpipe

im running xp, it works without batch files, i just use them to make things easier. what do you mean by gui progs?(like web browsers and stuff?) dont run them with netcat?
can u explain those nc commands a little bit? i've just been using nc to run cmd on port 1, then connecting to it with telnet, should i be using nc instead of telnet?

- Netcat can't provide an interface for graphical user interface tools (GUI).
- The following commands will let you connect from computer "A" (source;IP=10.10.10.1), bounce off of one (or more) "relay" computers "B" (relay;IP=10.10.10.2), and then shovel a command shell back from computer "C" (target;IP=10.10.10.3).

STEP 1) open a cmd window on computer "A"(source) and type:
nc -L -p 9998
STEP 2) open a cmd window on computer "C"(target) and type:
nc -L -p 9999 -e cmd.exe
STEP 3) open a cmd window on computer "B"(relay) and type:
nc -L -p 9997 | nc 10.10.10.3 9999 | nc 10.10.10.1 9998
STEP 4) open a second command window on computer "A" and type:
nc 10.10.10.2 9997

- On computer "A" (source) you will be entering commands in one window and the results will be visible in the other window.
(NOTE: "STEP 2" uses pipe characters "|" between the nc commands)

The problem may be with the telnet program. It is a graphical program instead
of a command line program, and may not run properly under a netcat session.
You could get a "console" telnet program or emulate telnet with netcat.
:cool:

for me the telnet prog is not graphical. at least i dont think it is graphical means it has all the icons and crazy windows stuff right? well the telnet im using just runs in the command prompt, so it should work, right?

Do you have a purpose? We may be able to help more if we knew it, there may be better solutions.

Also, when you telnet to another computer, then run 'telnet' on it, you are running the remote computers version of telnet, if it doens't have the command line version, then it will try and start up the goofy 9x version, which you can't use from the telnet command line. It's the same deal as if you tried running 'notepad' from your telnet window. It would start notepad on the remote computer. Notepad, of course, cannot be controlled or used from the command line, much like the goofy 9x version of telnet.

-Good day,

~Jon.

Quote:

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Originally posted here by UpperCell
Do you have a purpose? We may be able to help more if we knew it, there may be better solutions.

Also, when you telnet to another computer, then run 'telnet' on it, you are running the remote computers version of telnet, if it doens't have the command line version, Notepad, of course, cannot be controlled or used from the command line

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Quote:

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Originally posted here by UpperCell

Notepad, of course, cannot be controlled or used from the command line

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Actually...

echo blah>>C:\123.txt
notepad C:\123.txt

Running under under XP I am able to load text files and make the text appear to the user useing guess what? Yup... notepad under command promt so it really has a slightly bit more of a use rather than being called into action then just siting around with nothing to do. Oh and He has already mentioned "XP", "running stuff under DOS", & then there was this most recent post. In my eyes I beleave that he has made it beyond clear by now that he is useing the CLI version of telnet which by the way comes standard with XP. Hummm... so unless he downloaded another version and/or replaced the XP standard version with another... and is also really really really confused right now then I doubt he is useing it with some fancy GUI.

oh, I was like, why is the|Specialist talking like that? Wouldn't he get my point?

TheSpecialist? w/ 4 posts, yeah. ok, sorry.

You can't use notepad interactively from another computer, i.e. once you start it, without a third party program, terminal services (which, consequentially, I think may be what this dude is after), or some crazy trick messing with internal windows messaging remotely like some simpler trojans can do, you can't do much with notepad once it's started.

I did miss the crucial clue for running NT something, he hasn't mentioned what the other computers are specifically, but he did say they all called cmd.exe. I missed that, and that means he most likely has some NT version or above, quite posibbly xp, since he didn't think it necessary to be specific.

Oh, your here phonedog911? didn't mean to talk about you in 3rd person. lol.

This will work, I've done it before just for fun. I'm doing some testing and such, since this topic has me interested again. I like zark0id's method, but I haven't gotten it to work myself. Speak of the devil:

zark0id:

Are you sure those should work? they don't work for me. It seems fairly reasonable logic, but it doesn't work as described for me. Yes, I changed the IP's :D I'm quite familiar with nc, and could come up with some similar things on my own, but yours are so simple. If your sure they'll work exactly as described, just let me know, and I'll just figure out why they don't work for me.

Thanks.

~jon.

so, why do programs like "netstat" work, but not progs like telnet and edit? those arent gui programs are they? they run in the command prompt

I'm not exactly sure why telnet doesn't work, since you've said all three computers have the command line version (this is correct right?) Edit doesn't work for technical reasons. The whole full screen thing and such.

Telnet has worked for me in the past. Not sure why it doesn't now. I may play around with it a bit.

So do you really have a purpose other than learning? That's just great, but I'd like to know just how to approach your problem. If it's a more practical reason, there may be better solutions. If it's to learn, we can give tips and links to gain knowledge.

UpperCell:
I wrote down the steps as I was doing it. It worked on my end.
(I guess I could have typed it wrong but I tried to be careful).

i actually am just trying to learn. i read a post on this forum about telnetting through 3 comps like a chain and i figured i could try that out.

The default setting for windows telnet server is NTLM authentication only. In order to use NC you have to change it to use plain text. Being as we’re talking command line here, enter tlntadmn, choose ‘3) Display / change registry settings’ then ‘7) NTLM’ and give it the value 0 (zero). This is not real secure to say the least but inside your home network for fun…what the hell. Don’t forget to include ‘-t’ in the NC args.

Oh yeah! Windows telnet does not allow a telnet session to be started from within the telnet shell but will allow a NC session. And if you plan to do a lot of command line work edlin is a good tool to learn as it works just great from within a shell and allows you to make changes to a single line without having to echo the whole dammed file.

As zark0id has said nc isn’t a GUI tool…it just sits there listening for incoming connections. The –v flag is pretty useless in a server use so try getting rid of it.