I am trying to connect a client machine to my java server which is running on
139.78.141.234 on port 8080. The ip address for client is 172.168.100.248. I am using this command:
telnet 192.168.100.248 23456 http://139.78.141.234:8080/my.html
but I don't understand where am I possibly going wrong, because it doesn't display the error message rather displays:
Usage: telnet [-8] [-E] [-L] [-S tos] [-a] [-c] [-d] [-e char] [-l user]
[-n tracefile] [-b hostalias ] [-r]
[host-name [port]]
When I use it with curl it works
curl -s http://139.78.141.234:9090/my.html
The correct usage would be
telnet 139.78.141.234 8080
Note that you simply put the port after the hostname/IP address and ommit the protocol description, like http, as this is only needed for your browser.
And also ommit the path to website so /mysite.html . To retrieve some html file via telnet you need to speak http with the webserver. This means after being connected you can send GET requests to retrieve the website you want.
Related
Unable to connect, And not sure how many ways I can type "bandit0" for a password
ssh is not telnet with its general syntax of telnet server port. I believe even in Windows the basic usage of ssh is like:
ssh [-p port] [user#]server [command]
You did ssh bandit0#bandit.labs.overthewire.org 2220. You connected to the default port (22) and 2220 was the command.
It so happens there is a server on port 22, but this is not the server that accepts the credentials you know.
The command 2220 was never invoked because you failed to authenticate in the first place. Instead of 2220 it could have been anything, it wouldn't be invoked either.
You want to connect like this:
ssh -p 2220 bandit0#bandit.labs.overthewire.org
if you do not have this problem "Too many authentication failures", use this:
ssh bandit0#bandit.labs.overthewire.org -p 2220
if you are a windows user, it is better to use PuTTY than cmd.exe to play this game:
host name: bandit.labs.overthewire.org
port: 2220
open
login as: bandit0
password: bandit0
done
Bandit
Hi my country blocked google.com anyway I have a virtual machine which is outside the country and have access to google. it has nginx & haproxy installed, based on my limited understanding these reverse proxy can do proxy to internal servers but is there anyway to let them do proxy to google.com directly?
Thanks so much.
Instead of using NGINX or HAPROXY to proxy some URL or google.com what you should do is use your VM as a proxy for the browser. Execute below on your machine
$ ssh -D 8123 -f -C -q -N sammy#example.com
Explanation of arguments
-D: Tells SSH that we want a SOCKS tunnel on the specified port number (you can choose a number between 1025-65536)
-f: Forks the process to the background
-C: Compresses the data before sending it
-q: Uses quiet mode
-N: Tells SSH that no command will be sent once the tunnel is up
This will open a socks proxy on 127.0.0.1:8123, you can set this in your browser and open google through your server.
For more detailed article refer to below
https://www.digitalocean.com/community/tutorials/how-to-route-web-traffic-securely-without-a-vpn-using-a-socks-tunnel
I am trying to understand why netcat listener isn't working in my Kali Linux VM. From what I understand,I open a terminal and open the port.
nc -l 155
Then, I open another terminal within my VM and use the following command to connect to that port number.
nc 127.0.0.1 155 (loopback IP address and same port number)
It was unsuccessful and since I am just a newbie in this field, I was hoping to get some assistance on this issue. However, I found a new way to execute this command but I am not understanding the logic behind why this new way works and not the original method that I learned in class. Thank you for your help in advance!
First of all, to elevate your self from newbie status, you have to understand what errors mean. "it was unsuccessful" is an insufficient description of your results for any real debugging. Probably, what happened was a valuable clue to the issue - you should have included that information. Furthermore, you really have to get your commands in the quetsion exactly right. Don't say you did one thing, then post a screenshot of something else happening. I'm not sure what the -e is supposed to be doing, but I don't find any record of it in my osx implementation or online man pages.
Different builds or implementations of netcat could differ, but from what I'm seeing from a netcat on my osx box, -p is not the right way to specify destination port.
$ nc localhost -p 1055
nc: missing hostname and port
usage: nc [-46AacCDdEFhklMnOortUuvz] [-K tc] [-b boundif] [-i interval] [-p source_port] [--apple-delegate-pid pid] [--apple-delegate-uuid uuid]
[-s source_ip_address] [-w timeout] [-X proxy_version]
[-x proxy_address[:port]] [hostname] [port[s]]
-p specifies source port. You don't usually need to specify this. Furthermore, you can't have a source and destination of the socket on the same box on the same port. Usually source port doesn't need to be specified.
Finally, ports under 1024 can only be allocated as root. Like most linux professionals, I don't run anything as root unless I really have to, so I changed to 1055 for this demonstration. One nc each in a termina window, typing messages in one print out the other side. Observe:
$ nc -l 1055
hi world
hi yourself, world!
$ nc localhost 1055
hi world
hi yourself, world!
server: nc -l ${port} > ${file}
local: nc ${ip} -z ${port} < ${file}
I am trying to follow a number of recipes which use netcat or ideally knc (kerberos netcat) to create a proxy; either to look at what is being piped through the proxy for debugging or to create an kerberos authenticated link over which I can tunnel some java based tcp server-to-server traffic.
Taking this example http://notes.tweakblogs.net/blog/7955/using-netcat-to-build-a-simple-tcp-proxy-in-linux.html the pattern seems to be something like:
mkfifo fifo
nc -l -p 8080 <fifo | nc tweakers.net 80 >fifo
Yet that gives the error:
usage: nc [-46DdhklnrStUuvzC] [-i interval] [-p source_port]
[-s source_ip_address] [-T ToS] [-w timeout] [-X proxy_version]
[-x proxy_address[:port]] [hostname] [port[s]]
Yet if I run ether side of the pipe alone I get no error:
nc -l -p 8080 <fifo
nc tweakers.net 80 >fifo
What am I missing to get this to work?
I am running Red Hat Enterprise Linux Server release 6.2 (Santiago) either bash or ksh.
Annoyingly it was the -p option which was tripping things up. The following command runs fine:
nc -l 8080 <fifo | nc somehost.com 80 >fifo
Then in another shell doing
telnet localhost 8080
get /
works fine.
I am using netcat utility on linux to receive outputs from a program on a windows machine. My problem being that the program on the windows machine does not always give an output.
How can i check that either a connection has been made to netcat ?
What i am doing till now is "nc -l -v 9103 > output" then i check the size of output, the problem this poses is that netcat only write to a file after a certain buffer size has been reached or a new line char is encountered, so some cases evne though a connection has been made the file size is detected as zero.
How can i check if someone has made a connection with netcat.
I tried using
nc -l -v -e someprog.exe 9103 > output
but my netcat doesnt seem to support this
below are the options i have
$ nc -h
usage: nc [-46DdhklnrStUuvzC] [-i interval] [-p source_port]
[-s source_ip_address] [-T ToS] [-w timeout] [-X proxy_version]
[-x proxy_address[:port]] [hostname] [port[s]]
Command Summary:
-4 Use IPv4
-6 Use IPv6
-D Enable the debug socket option
-d Detach from stdin
-h This help text
-i secs Delay interval for lines sent, ports scanned
-k Keep inbound sockets open for multiple connects
-l Listen mode, for inbound connects
-n Suppress name/port resolutions
-p port Specify local port for remote connects
-r Randomize remote ports
-s addr Local source address
-T ToS Set IP Type of Service
-C Send CRLF as line-ending
-t Answer TELNET negotiation
-U Use UNIX domain socket
-u UDP mode
-v Verbose
-w secs Timeout for connects and final net reads
-X proto Proxy protocol: "4", "5" (SOCKS) or "connect"
-x addr[:port] Specify proxy address and port
-z Zero-I/O mode [used for scanning]
Port numbers can be individual or ranges: lo-hi [inclusive]
verbose mode will write connectivity to stderr, and you can redirect stderr to a file, the verbose log has something like
connect to [xxx] from [xxxx]
try
nc -l -v -p 9103 -k 1> output 2>connect.log
and monitor connect.log for connectivity
if you don't use -k , netcat quits after 1st connection.
If you can upgrade your copy of netcat: the modern versions (1.10, for one) have an option to execute a program (or a shell command) upon connect. Otherwise, you can make the netcat think it runs in a terminal (to disable buffering of stdout), by using for example script (it just saves everything on stdin/stdout/stderr in the given file). Or use logging features of screen and tmux.