Added netcat cheatsheet

cheatsheets/netcat.rb

@@ -0,0 +1,154 @@
+cheatsheet do
+  title 'Netcat'
+  docset_file_name 'netcat-cheatsheet'
+  keyword 'netcat'
+
+  introduction 'Netcat cheat sheet'
+
+  category do
+    id 'Usage'
+    entry do
+      name 'Normal Syntax'
+      notes <<-'END'
+      Usage:
+        ```
+        nc [options] [host] [port]
+        ```
+        arbitrary TCP and UDP connections and listens
+      END
+    end
+  end
+
+  category do
+    id 'General Options'
+    entry do
+      name 'Use IPv4 addressing only'
+      command 'nc -4 [options] [host] [port]'
+    end
+
+    entry do
+      name 'Use IPv6 addressing only'
+      command 'nc -6 [options] [host] [port]'
+    end
+
+    entry do
+      name 'UDP instead of TCP'
+      command
+        'nc -u [options] [host] [port]'
+    end
+
+    entry do
+      name 'Listen for an incoming connection'
+      command 'nc -l [host] [port]'
+    end
+
+    entry do
+      name 'Continue listening after client has disconnected'
+      command 'nc -k -l [host] [port]'
+    end
+
+    entry do
+      name 'No DNS lookups'
+      command 'nc -n [host] [port]'
+    end
+
+    entry do
+      name 'Use specific source port'
+      command 'nc -p [source port] [host] [port]'
+    end
+
+    entry do
+      name 'Use source IP'
+      command 'nc -s [source ip] [host] [port]'
+    end
+
+    entry do
+      name 'Apply \'n\' second timeout'
+      command 'nc -w [timeout] [host] [port]'
+    end
+
+    entry do
+      name 'Verbose output'
+      command 'nc -v [host] [port]'
+    end
+  end
+
+  category do
+    id 'Client Examples'
+    entry do
+      name 'Transmit contents of file "filename.in"'
+      command 'nc 192.168.0.1 5051 < filename.in'
+    end
+
+    entry do
+      name 'Send incoming data to "filename.out"'
+      command 'nc 192.168.0.1 5051 > filename.out'
+    end
+  end
+
+  category do
+    id "Server Examples"
+
+    entry do
+      command 'netcat -l 5050'
+	    notes 'Listen for TCP connections (port 5050). Data received is directed to STDOUT. Data is captured and transmitted from STDOUT'
+    end
+
+    entry do
+      command 'netcat -l 5051 > filename.out'
+      notes ' Data received directed to "filename.out"'
+    end 
+
+    entry do
+      notes <<-'END'
+      ```
+      ( echo -ne "HTTP/1.1 200 OK
+      Content-Length: $(wc -c <index.html)\r\n\r\n" ; cat index.html ) | nc -l 8080
+      ```
+      END
+      name 'Single use web server listening on port 8080'
+    end
+
+    entry do
+      notes <<-'END'
+      ```
+      while : ; do ( echo -ne "HTTP/1.1 200 OK\r\nContent-Length: $(wc -c <index.html)\r\n\r\n" ; cat index.html; ) | nc -l -p 8080 ; done
+      ```
+      END
+      name 'Bash while loop restarts web server after each request'
+    end
+  end
+
+    category do
+      id "Simple Proxy"
+
+      entry do
+        notes <<-'END'
+        ```
+        mknod backpipe p ; nc -l [proxy port] < backpipe | nc [destination host] [destination port] > pipe
+        ```
+        END
+        name 'Created a named pipe. Setup an a listener on proxy port. Forward requests from listener to a client which in-turn sends them onto the destination host. The client redirects the response from the destination host into the named pipe. The listener picks up the response from the named pipe and returns it. The named pipe thus allows the proxy to transmit data bi-directionally.'
+      end
+    end
+
+  category do
+    id "Port Scanning"
+
+    entry do
+      name 'Scan a single TCP port'
+      command 'nc -zv hostname.com 80'
+    end
+
+    entry do
+      name 'Scan a range of ports'
+      command 'nc -zv hostname.com 80-84'
+    end
+
+    entry do
+      name 'Scan multiple ports'
+      command 'nc -zv hostname.com 80 84'
+    end
+  end
+  notes "Thanks to (biscuitNinja)[http://duckduckhack.com/u/biscuitninja] and the (DuckDuckGo Cheatsheet)[https://duck.co/ia/view/netcat_cheat_sheet]."
+end