PowerShell: MD5/SHA1 hashes of files

Problem Statement: I need to get Signatures (MD5 and SHA1) of all the files present at a certain location on the hard disk.
Utility: This could be for checking the signature of the files present in the downloaded build for correctness or if need be for whitelisting of files.
Here's a small PowerShell script

function Get-Md5{
param ($file)
$input = get-content -encoding byte -readcount -1 $file$md5 = [System.Security.Cryptography.MD5]::Create()
$output = $md5.ComputeHash($input)$sb = new-object Text.StringBuilder
foreach ($b in $output) {
[void] $sb.Append($b.ToString("X2"));
}
$sb.ToString()
}function Get-SHA1{param ($file)
$input = get-content -encoding byte -readcount -1 $file$sha1 = [System.Security.Cryptography.SHA1]::Create()
$output = $sha1.ComputeHash($input)
$sb = new-object Text.StringBuilder
foreach ($b in $output) {
[void] $sb.Append($b.ToString("X2"));
}
$sb.ToString()
}
"MD5`tSHA1`tFilePath" out-file C:\Hashes.xls -append$files = get-childitem $args -recurse -include *.*
foreach ($i in $files) {
$md5 = get-md5 $i $sha1 = get-sha1 $i "$md5`t$sha1`t$i" out-file C:\Hashes.xls -append
}
Hope this helps.

Batch: '-' issues

Today, I encountered something unusual at work.

~ I had an application (say app.exe) that accepted parameters; for e.g., if "App.exe -i" command is executed, the application would get installed on the system.
~ Also, I had a BATCH script that would call App.exe with options for further processing.
But somehow the script didn't run effectively. I had to use the command, "App.exe -i" in the script and when I ran the script, to my surprise, I could see the command being executed as "App.exe ϋi" instead of "App.exe -i". That is, instaed of "-" it ran as "ϋ" on the command prompt.
Where did this "ϋ" come from??

After struggling for an hour or so I could gauge that the "ϋ" sign was because of the space between App.exe and -i in the command.

The simple solution was to use a ESCAPE sequence before the space. Hence I scripted the command as "App.exe^ -i". where ^ is the escape sequence in DOS and then space was no more an issue.

Interesting isn't it!! :-)

Powershell-GUI: EventLog Manager

Problem Statement: Recently. there was a requirement for me to clear or save event logs of different systems on the network. The number of systems in the network were at least 10 and the requirement demanded that I had to Save Event logs or Clear Event Logs on all/selected servers (separated by commas), in one go!



Now here's what I came up with:






Script:
Function Main{
[reflection.assembly]::LoadWithPartialName( "System.Windows.Forms")
$form = New-Object Windows.Forms.Form $form.text = "Event Log Manager"
$form.height = 400
$label_logname = New-Object Windows.Forms.Label
$label_logname.Location = New-Object Drawing.Point 50,30
$label_logname.Size = New-Object Drawing.Point 200,30
$label_logname.text = "Enter the EventLog Name"
$combo = new-object System.Windows.Forms.ComboBox
$combo.Location = new-object System.Drawing.Size(50,60)
$combo.Size = new-object System.Drawing.Size(200,15)
$combo.Items.Add("Enter EventLog") $combo.Items.Add("Application")
$combo.Items.Add("System")
$label_server = New-Object Windows.Forms.Label
$label_server.Location = New-Object Drawing.Point 50,110
$label_server.Size = New-Object Drawing.Point 200,30
$label_server.text = "Enter the Server Names separated by commas"
$combo1 = new-object System.Windows.Forms.ComboBox
$combo1.Location = new-object System.Drawing.Size(50,150)
$combo1.Size = new-object System.Drawing.Size(200,15)
$combo1.Items.Add("10.2.2.3")
$button = New-Object Windows.Forms.Button
$button.text = "Save EventLog"
$button.Location = New-Object Drawing.Point 50,200
$button.Size = New-Object Drawing.Point 200,25
$button1 = New-Object Windows.Forms.Button
$button1.text = "Clear EventLog"
$button1.Location = New-Object Drawing.Point 50,250
$button1.Size = New-Object Drawing.Point 200,25
$button2 = New-Object Windows.Forms.Button
$button2.text = "Quit..."
$button2.Location = New-Object Drawing.Point 50,300
$button2.Size = New-Object Drawing.Point 200,25
$button.add_click({ $form.hide()
SaveEvtLog $combo1.text $combo.text })
$button1.add_click({ $form.hide()
ClearEvtLog $combo1.text $combo.text })
$button2.add_click({ $form.dispose() })
$form.controls.add($button)
$form.controls.add($label_logname)
$form.controls.add($label_server)
$form.controls.add($button1)
$form.controls.add($button2)
$form.controls.add($combo)
$form.controls.add($combo1)
$form.ShowDialog()
}

Function SaveEvtLog {
param ($computer,$evtlog)
$servers = $computer.split(',')
foreach ($server in $servers) {
[reflection.assembly]::LoadWithPartialName( "System.Windows.Forms")
$form1 = New-Object Windows.Forms.Form $form1.height = 300 $form1.width = 300 $label2 = New-Object Windows.Forms.Label
$label2.Location = New-Object Drawing.Point 50,30
$label2.Size = New-Object Drawing.Point 200,90
$ALive=get-wmiobject win32_pingstatus -Filter "Address='$server'" Select-Object statuscode
if($ALive.statuscode -ne 0)
{ "Host $server is Unreachable...`n" out-file log.txt -append }
else { $filename = "Log_" + $evtlog + "_" + $server + ".evt"
if((Test-Path -path c:\$filename) -ne $False) { remove-item C:\$filename } wmic /node:"$server" nteventlog where "logfilename='$evtlog'" call backupeventlog "C:\$filename" out-file null
remove-item null
copy-item file://$server/c$/$filename C:\
remove-item file://$server/c$/$filename
$lbl_text = "EventLog copied at c:\$filename" out-file log.txt -append } }
$lbl = get-content log.txt
$label2.text = $lbl
$button4 = New-Object Windows.Forms.Button
$button4.text = "Back to Main..."
$button4.Location = New-Object Drawing.Point 50,180
$button4.Size = New-Object Drawing.Point 200,25 remove-item log.txt
$button4.add_click({ $form1.hide()
Main })
$form1.controls.add($label2)
$form1.controls.add($button4)
$form1.ShowDialog() }

Function ClearEvtLog {
param ($computer,$evtlog)
$servers = $computer.split(',')
foreach ($server in $servers) {
[reflection.assembly]::LoadWithPartialName( "System.Windows.Forms")
$form1 = New-Object Windows.Forms.Form
$form1.height = 300 $form1.width = 300
$label2 = New-Object Windows.Forms.Label
$label2.Location = New-Object Drawing.Point 50,30
$label2.Size = New-Object Drawing.Point 200,90
$ALive=get-wmiobject win32_pingstatus -Filter "Address='$server'" Select-Object statuscode
if($ALive.statuscode -ne 0)
{ "Host $server is Unreachable...`n" out-file evt.txt -append }
else { $logs = [System.Diagnostics.Eventlog]::GetEventLogs("$server")
$Applogs = $logswhere-object {$_.logdisplayname -eq "$evtlog" }
if($Applogs -ne $null)
{$Applogs.clear()
"$evtlog Event Log Cleared at $server `n" out-file evt.txt -append}
else {"Event log is already cleared or it doesnt exist `n" out-file evt.txt -append} } } $lbl = get-content evt.txt
$label2.text = $lbl
$button4 = New-Object Windows.Forms.Button
$button4.text = "Back to Main..."
$button4.Location = New-Object Drawing.Point 50,180
$button4.Size = New-Object Drawing.Point 200,25 remove-item evt.txt
$button4.add_click({ $form1.hide()
Main })
$form1.controls.add($label2)
$form1.controls.add($button4)
$form1.ShowDialog() }

Main



Hope this helps!! Let me know your comments...

PERL: Base64 Encoding

What is Base64: Base64 is MIME character tranafer encoding...Its like any other encoding that uses a-zA-Z0-9/+ (64 characters and = for padding) for converting the string...An important encoding format....Between, have you wondered if we could use a Base64 encoded string as a filename?? Think??

Here's a small PERL script that would help you in encoding and decoding the input string:

C0de:
#! /usr/bin/perl
use MIME::Base64;
print "Enter the Choice\n";
print "1. Encode to Base 64\n";
print "2. Decode from Base64\n";print "Enter the choice::";
my $choice=<STDIN>;
if($choice==1)
{ print "Please enter a string that is to be encoded:"; my $str=; my $encode=encode_base64($str); print "String ENCODED as:$encode"; }
if($choice==2)
{ print "Please enter a Base 64 string that is to be decoded:"; my $str=; my $decode=decode_base64($str); print "String DECODED as:$decode"; }

Hope this helps!!!

PowerShell: Script for getting the inventory details....

Hya!! After a long gap, I am here again...
This time I have come up with an utility that takes the details of your inventory.

Problem Statement: I have a lot of servers on my network and my manager comes and tell me, "Can you get me details like the total RAM, HDD, Manufacturer, Serial Number and ServerName of all these servers?? I need to report this to Infrastructure team! Please get this in 2 hours time!!" Sounds laborious..Isn't it??

Here's the script:

"IP`tHardDisk`tRAM`tSystemName`tManufacturer`tSerialNumber" out-file C:\Results.csv -append

Function HDDInfo { param($ip) $alldrives = get-wmiobject win32_logicaldisk -filter "DriveType=3" -computername $ip $HDD = 0 foreach ($i in $alldrives) { $HDD = $HDD + ($i.size)/(1gb) } $HDD }

Function RAMInfo { param($ip) $ram = get-wmiobject win32_ComputerSystem -computername $ip $RAM = ($ram.TotalPhysicalMemory)/(1gb) $RAM }

Function SystemName { param($ip) $bios = get-wmiobject win32_bios -computer $ip $bios.name }

Function Manufacturer { param($ip) $bios = get-wmiobject win32_bios -computer $ip $bios.manufacturer } Function SerialNumber { param($ip) $bios = get-wmiobject win32_bios -computer $ip $bios.SerialNumber }

$address = "10.2.2."
2..254 foreach-object { $ip = $address + $_
$ping = get-wmiobject win32_pingstatus -filter "Address = '$ip'" select-object statuscode
if($ping.statuscode -eq 0) { $HDD = HDDInfo $ip sleep 1 $RAM = RAMInfo $ip sleep 1 $SystemName = SystemName $ip $Manufacturer = Manufacturer $ip $SerialNumber = SerialNumber $ip
"$ip`t$HDD`t$RAM`t$SystemName`t$Manufacturer`t$SerialNumber" out-file C:\Results.csv -append } else { "$ip is Offline or Not Reachable.." out-file C:\Results.csv -append }
}


In this script, I assume all your systems on the network are in the IP range of 10.2.2.x and I am collecting the details of IPs: 10.2.2.2 - 10.2.2.254

Run the script, wait for 4-5 minutes and get the results in Results.csv file. :-)

Hope this helps!!

PowerShell: OS Statistics for a Remote Host

Here's a small PowerShell Script that would enable you to get the OS Statistics for a Host...
----------OS-Statistics.ps1------------------
Function Main {
# Load the Winforms assembly
[reflection.assembly]::LoadWithPartialName( "System.Windows.Forms")
# Create the form
$form = New-Object Windows.Forms.Form
#Set the dialog title
$form.text = "OS Statistics"














# Create the label control and set text, size and location
$label = New-Object Windows.Forms.Label
$label.Location = New-Object Drawing.Point 50,50
$label.Size = New-Object Drawing.Point 200,15
$label.text = "Enter Hostname"

$combo = new-object System.Windows.Forms.ComboBox
$combo.Location = new-object System.Drawing.Size(50,80)
$combo.Size = new-object System.Drawing.Size(200,25)
$combo.Items.Add("ComputerName / IP")
$combo.Items.Add("192.168.219.")
$combo.Items.Add("127.0.0.1")

# Create Button and set text and location
$button = New-Object Windows.Forms.Button
$button.text = "Get OS Statistics"
$button.Location = New-Object Drawing.Point 50,130
$button.Size = New-Object Drawing.Point 200,25

$button3 = New-Object Windows.Forms.Button
$button3.text = "Quit...."
$button3.Location = New-Object Drawing.Point 50,180
$button3.Size = New-Object Drawing.Point 200,25

# Set up event handler to extarct text from TextBox and display it on the Label.
$button.add_click({ NewForm $combo.text })
$button3.add_click({ $form.dispose() })

# Add the controls to the Form
$form.controls.add($button)
$form.controls.add($button3)
$form.controls.add($label)
$form.controls.add($combo)

# Display the dialog
$form.ShowDialog()
}

Function NewForm
{
Param ($ip)

$ALive=get-wmiobject win32_pingstatus -Filter "Address='$ip'" Select-Object statuscode
if($ALive.statuscode -ne 0)
{
[reflection.assembly]::LoadWithPartialName( "System.Windows.Forms")
$form1 = New-Object Windows.Forms.Form
$form1.height = 180
$label1 = New-Object Windows.Forms.Label
$label1.Location = New-Object Drawing.Point 50,10
$label1.Size = New-Object Drawing.Point 200,50
$label1.text = "Sorry!! The Host is Unreachable `n`n Check if" + $ip + " is Online..."
$button2 = New-Object Windows.Forms.Button
$button2.text = "Click to Get Back"
$button2.Location = New-Object Drawing.Point 50,80
$button2.Size = New-Object Drawing.Point 200,25
$button2.add_click({
$form1.dispose()
})
$form1.controls.add($button2)
$form1.controls.add($label1)
$form1.showdialog()
}
























else{
[reflection.assembly]::LoadWithPartialName( "System.Windows.Forms")
$form1 = New-Object Windows.Forms.Form
$form1.height = 600
$form1.width = 300
$label1 = New-Object Windows.Forms.Label
$label1.Location = New-Object Drawing.Point 50,10
$label1.Size = New-Object Drawing.Point 200,600
$perf= get-wmiobject Win32_PerfFormattedData_PerfOS_System -computer $ip
$uptime=$perf.SystemUpTime/3600
$freedisk = get-wmiobject win32_logicaldisk -filter "DriveType=3" -computer $ip foreach-object {"`n{0} {1}" -f $_.DeviceID,($_.freespace/1gb)}
$result = "`n--------------------------------------------`n" + "OS STATISTICS :: " + $ip + "`n--------------------------------------------`n`n" + "Processes:`t" + $perf.Processes + "`n`nThreads:`t" + $perf.Threads + "`n`nSystem UpTime In hours:`t" + $uptime + "`n`nAlignment Fixups/sec:`t" + $perf.AlignmentFixupsPersec + "`n`nContext Switches/sec:`t" + $perf.ContextSwitchesPersec + "`n`nException Dispatches/sec:`t" + $perf.ExceptionDispatchesPersec + "`n`nFile Control Bytes/sec:`t" + $perf.FileControlBytesPersec + "`n`nFile Control Operations/sec:`t" + $perf.FileControlOperationsPersec + "`n`nFile Data OperationsPersec:`t" + $perf.FileDataOperationsPersec+ "`n`nFile Read Bytes/sec:`t" + $perf.FileReadBytesPersec + "`n`nFile Read Operations/sec:`t" + $perf.FileReadOperationsPersec + "`n`nFile Write Bytes/sec:`t"+ $perf.FileWriteBytesPersec +"`n`nFile Write Operations/sec:`t" + $perf.FileWriteOperationsPersec + "`n`nSystem Calls/sec:`t"+ $perf.SystemCallsPersec + "`n`nFree Disk Space in GB:`n" + $freedisk
$label1.text = "$result"
$button1 = New-Object Windows.Forms.Button
$button1.text = "Click to Get Back"
$button1.Location = New-Object Drawing.Point 50,520
$button1.Size = New-Object Drawing.Point 200,25
$button1.add_click({
$form1.dispose()
})
$form1.controls.add($button1)
$form1.controls.add($label1)
$form1.showdialog()
}

}

Main

PowerShell<->Perl: Reading UNICODE files

Problem Statement:
Recently, I faced a tricky situation at work. I had a CSV file generated out of a PowerShell script. I was trying to read the CSV file and generate a graph using Perl TK module. To my surprise, no value from the CSV file got plotted on the graph! Why would this happen?

Reason:
After some tussle, I found that, this was because PowerShell generated the CSV file in a UNICODE format. PERL opens the Unicode file but can’t recognize the content. This is because “Unicode format is not a character encoding”. Hence the issue!

Resolution:
In such cases, one needs to open the Unicode files using any other Perl supported encoding format. Say, we open the file as:
Open (FH, “<:utf-8”, “filepath”);
OR
Open (FH, “<:encoding(utf-8)”, “filepath”);

Thus, Unicode text files are read exactly the same way that other files are read: by specifying a text encoding.