Network

PowerShell TCP Socket Function

/ PowerShell Scripting /

The PowerShell function example below can be used to transmit information using the TCP protocol. For example, to perform an HTTP GET command on a website.

function fnTCPSock([string]$sHostName, [string]$sPort, [string]$sScript) {
  # Converteer script string to byte for write stream...
  [byte[]]$byteScript = [System.Text.Encoding]::ASCII.GetBytes($($sScript))
  # Open 4096 Bytes buffer for read stream...
  [byte[]]$byteBuffer = New-Object System.Byte[] 16384
  
  # Connect to host...
  $oTCPSock = New-Object System.Net.Sockets.TcpClient($sHostName, $sPort)
  $oStream = $oTCPSock.GetStream() 
  
  # Feed script(byte) tot write stream...
  $oStream.Write($byteScript, 0, $byteScript.Length)

  # Return read buffer converted to string...
  [string]$sCount = $oStream.Read($byteBuffer, 0, 16384)
  return [System.Text.Encoding]::ASCII.GetString($byteBuffer, 0, $sCount) 

  # Close objects...
  $oResult.Close()
  $oSockTCP.Close()
}
[string]$sScript1 = "GET / HTTP/1.1`r`nAccept: text/html`r`nHost: [virtualhostname]`r`nReferer: http://host.domain.name/site/`r`n`r`n`r`n"
[string]$sResult1 = fnTCPSock "hostname" "80" $($sScript1)

Netwerk IPv4 Subnetting

/ Other / 
max aantal subnetten: 2^n (-2) // n = aantal masked bits *subnet* mask
max aantal hosts in subnet = 2^n -2 // n = ongemaskeerde bits

next multiple of 8 = next mult. of 8 greater or eq. to CIDR netmask not.
interesting value = (next multiple of 8) / 8

incremental value = 2^ (next multiple of 8 - CIDR netmask notation)

bijv. 192.168.10.50/27:
incremental value = 2^(32-27) = 2^5 = 32
interesting value = 32 / 8 = 4
netwerkadressen: 192.168.10.0, 192.168.10.32, 192.168.10.64, enz.
broadcastadressen: 192.168.10.31, 192.168.10.63, 192.168.10.95, enz.
netwerk 192.168.10.32
broadcast 192.168.1.63 (192.168.10.(64-1))

bijv. 10.6.127.255/14:
incremental value: 2^(16-14) = 2^2 = 4
interesting value = 16 / 8 = 2
netwerkadres: 10.4.0.0
broadcast: 10.7.255.255 ( 10.(8.0.0-1)