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I'm working on homework assignment for my college. Task is to fetch web page on HTTPS using nc (netcat).

To fetch a page over HTTP, I do this:

cat request.txt | nc -w 5 <someserver> 80

In request.txt I have HTTP 1.1 request

GET / HTTP/1.1
Host: <someserver>

Now... This works fine. How can I fetch web page that uses HTTPS?

I get page certificate like this. And this is the point in which I'm stuck

openssl s_client -connect <someserver>:443
  • socat - OPENSSL would work, but that's probably not your assignment. – Tobu Jan 12 '10 at 21:19
  • s/collage/college/, s/witch/which/ – Jukka Dahlbom Dec 20 '12 at 8:39
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    You can use bash redirection to avoid using cat, i.e. nc -w 5 <someserver> 80 < request.txt. – RastaJedi Aug 3 '16 at 5:39
  • See What's the alternative to “nc -l” for HTTPS? for the other way around. – Nickolay Aug 12 '19 at 2:27
59

nc doesn't do https. openssl s_client is as close as you'll get. Do something like this:

$ cat request.txt | openssl s_client -connect server:443
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  • 3
    I mean, unless your assignment is to write some code that does the SSL. That would be StackOverflow territory :) – Bill Weiss Jan 12 '10 at 20:44
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    I've tried this, but I do not get what the server send back to me in stdout... – Dog eat cat world Feb 17 '15 at 22:24
36

ncat --ssl

sudo apt-get install nmap
printf 'GET / HTTP/1.1\r\nHost: github.com\r\n\r\n' | ncat --ssl github.com 443

Same on Super User: https://superuser.com/questions/346958/can-the-telnet-or-netcat-clients-communicate-over-ssl

Tested on Ubuntu 18.04.

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  • is there any way to take your command and pass username and password commands into it for https sites that require authentication? – user53029 Mar 16 '16 at 12:52
  • @user53029 I think not for most websites, where authentication works by filling a form and giving you a session cookies. Unless it is one of the very few websites that uses other methods of authentication like en.wikipedia.org/wiki/Basic_access_authentication. You could also manually fill the form, and then send the cookie while it is valid. Or if you are desperate use stackoverflow.com/questions/13376189/… – Ciro Santilli 郝海东冠状病六四事件法轮功 Mar 16 '16 at 12:58
  • ncat is not nc, ncat does not support keep connection on send the payload like as nc. The question require a objetive response using nc not others apps. – e-info128 Apr 25 '18 at 11:56
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    @e-info128 thanks for that info. My philosophy is: when I google for something, and I click on this page, will I find the answer that I want. – Ciro Santilli 郝海东冠状病六四事件法轮功 Apr 25 '18 at 12:30
  • what is sudo apt-get install nmap?? – Alexander Mills May 20 '19 at 1:50
6

You probably want to use stunnel.

A GNU program allowing to encrypt arbitrary TCP connections inside Secure Sockets Layer (SSL).

http://www.stunnel.org

It's very UNIX-y. One great tool for one simple task.

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  • 1
    stunnel + nc would work, I suppose. Good thought. – Bill Weiss Jan 13 '10 at 15:56
3

Ask the prof or TA for assistance. You would never try to do HTTPS over netcat in the real world (openssl s_client would be my first-line tool of choice, but there are other options) so the chances of finding the "right" answer that the prof wants by asking people in the real world is low. I'd probably go over all the slides/notes from the lectures; typically these sorts of "impossible" questions are actually answered in the lectures, and asked just to see who is actually paying attention in class.

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