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| deostroll... |
 Posted: Sat Oct 24, 2009 2:40 am |
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Guest
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Hi,
I am not that experienced with tcp programming. Lately I am trying to
understand how I can respond to server acknowledgements. I guess they come
into picture only if you send some IAC DO instructions to the server. I am
not sure though. I have posted a full account of my problem over at (no spam) msdn
forums. Not got a response so far. Below is the link to it:
http://social.msdn.microsoft.com/Forums/en-US/netfxnetcom/thread/1693020a-0e17-40b5-8868-53df02228eae
Hoping I can find some advice. Thanx in advance.
--deostroll |
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| Goran Sliskovic... |
| Posted: Sat Oct 24, 2009 9:01 am |
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Guest
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"deostroll" <deostroll at (no spam) discussions.microsoft.com> wrote in message
news:0FC80D24-DC75-4E8A-9476-891FA26E5B74 at (no spam) microsoft.com...
Quote: Hi,
I am not that experienced with tcp programming. Lately I am trying to
understand how I can respond to server acknowledgements. I guess they come
into picture only if you send some IAC DO instructions to the server. I am
not sure though. I have posted a full account of my problem over at (no spam) msdn
forums. Not got a response so far. Below is the link to it:
http://social.msdn.microsoft.com/Forums/en-US/netfxnetcom/thread/1693020a-0e17-40b5-8868-53df02228eae
Hoping I can find some advice. Thanx in advance.
--deostroll
The acknowledgment you are talking about is internal to TCP protocol. It's
not passed to an application and the application does not need to respond to
it (it can't). OS will handle that. Your problem is somwhere in the
implementation of telnet protocol.
Regards,
Goran |
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| deostroll... |
| Posted: Sun Oct 25, 2009 10:32 am |
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Guest
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Quote: Your problem is somwhere in the
implementation of telnet protocol.
Goran
So how do I implement it? I hope u see there is a challenge here. I
don't exactly understand what I have to send to the remote machine via
telnet. I have to keep discovering that using the wireshark tool...
--deostroll |
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| Goran Sliskovic... |
| Posted: Mon Oct 26, 2009 4:08 pm |
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Guest
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"deostroll" <deostroll at (no spam) gmail.com> wrote in message
news:0012f052-5e15-47b6-a736-f0dbdd90787b at (no spam) v15g2000prn.googlegroups.com...
Quote: Your problem is somwhere in the
implementation of telnet protocol.
Goran
So how do I implement it? I hope u see there is a challenge here. I
don't exactly understand what I have to send to the remote machine via
telnet. I have to keep discovering that using the wireshark tool...
--deostroll
Telnet protocol is specified in:
http://www.faqs.org/rfcs/rfc854.html
There are probably lot resources on the internet about telnet protocol.
Reverse engineering using wireshark is a bit tricky and unnecessary IMHO.
Regards,
Goran |
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| deostroll... |
| Posted: Tue Oct 27, 2009 9:40 am |
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Guest
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Quote: Telnet protocol is specified in:http://www.faqs.org/rfcs/rfc854.html
Goran
I still can't develop a NVT just by reading that...are there any texts/
books which explain how to go about implementing it...?
--deostroll |
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| Goran Sliskovic... |
| Posted: Wed Oct 28, 2009 3:58 pm |
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Guest
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"deostroll" <deostroll at (no spam) gmail.com> wrote in message
news:08d31853-51f2-4067-99a7-5df6cc340f72 at (no spam) y28g2000prd.googlegroups.com...
Quote: Telnet protocol is specified in:http://www.faqs.org/rfcs/rfc854.html
Goran
I still can't develop a NVT just by reading that...are there any texts/
books which explain how to go about implementing it...?
--deostroll
Shouldn't be so difficult, you probably could implement only few options and
refuse most... Anyway, there are lot of free telnet clients with source code
available on the internet:
http://www.google.hr/search?q=telnet+client+source
Regards,
Goran |
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| deostroll... |
| Posted: Thu Oct 29, 2009 2:00 am |
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Guest
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Thanx I did find a good library on sourceforge. Now I am able to send
commands and navigate to menus, etc. But I've stumbled over another
problem...parsing the data I receive over the socket. I remove all those
chars which do not fall in the set of alphabets. I allow normal puncutations
and numbers too to appear...but it seems there are sequences of characters
which make no sense (and which fall in the above range) "interspersed"
between text I am looking for. What do you know about parsing such kind of
data?
--deostroll |
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| deostroll... |
| Posted: Thu Oct 29, 2009 6:13 am |
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Guest
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New development:
The data I am talking about prints correctly in a unix shell. I.e. if you
use an "echo -e " followed by the data you've received in single quotes (viz
denotes a string in unix shell) it prints exactly the way I can see on the
windows command prompt using telnet.exe - the command-line tool for
telnetting.
Do you know anything that does something similar to this? I am looking at
retaining the "transformed" string into memory so I can later work with it...
--deostroll |
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| Goran Sliskovic... |
| Posted: Fri Oct 30, 2009 5:10 pm |
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Guest
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"deostroll" <deostroll at (no spam) discussions.microsoft.com> wrote in message
news:DA414151-D093-4004-BDB1-1AEF8E0A676A at (no spam) microsoft.com...
Quote: New development:
The data I am talking about prints correctly in a unix shell. I.e. if you
use an "echo -e " followed by the data you've received in single quotes
(viz
denotes a string in unix shell) it prints exactly the way I can see on the
windows command prompt using telnet.exe - the command-line tool for
telnetting.
Do you know anything that does something similar to this? I am looking at
retaining the "transformed" string into memory so I can later work with
it...
--deostroll
These are probably terminal control characters (aka non-printables)... For
example, cursor left, down etc... I think there are many types of virtual
terminals, but checking VT100 is probably a good guess for a start.
http://www.cs.utk.edu/~shuford/terminal/vt100_codes_news.txt
Regards,
Goran |
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