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diff --git a/writeups/powershell-email/sendmail.ps1 b/writeups/powershell-email/sendmail.ps1
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+#!/usr/bin/env pwsh
+
+# Send an email using Powershell.
+# Usage: sendmail.ps1 [attachment 1 [attachment 2 [... attachment N]]]
+#
+# This is a POC on how to send an email using Powershell. The script should work
+# on all platforms. The information required for the script to work is all
+# supplied via environment variables.
+#
+# Env Vars
+#   smtp_host
+#   smtp_port (best if you let the implementation decide)
+#   smtp_tls:
+#     'F' to insist on secure connection (default)
+#     'O' for opportunistic
+#     'N' to disable (default if $smtp_host is "localhost")
+#   smtp_tls_cert
+#   smtp_username
+#   smtp_password
+#   mail_from (required)
+#   mail_to (required)
+#   mail_subject (required)
+#
+# Example
+#```pwsh
+#   echo 'Hi! it going? Testing my Powershell script.' | \
+#     smtp_host=smtp.gmail.com \
+#     smtp_username=example@gmail.com \
+#     smtp_password='0123456789' \
+#     mail_from=alice@gmail.com \
+#     mail_to=bob@example.com \
+#     mail_subject='Sent using Powershell' \
+#      sendmail.ps1 \
+#        doc.pdf
+#```
+using namespace System
+using namespace System.Net
+using namespace System.Security.Cryptography
+
+Set-StrictMode -Version Latest
+$ErrorActionPreference = "Stop"
+$PSDefaultParameterValues['*:ErrorAction'] = 'Stop'
+
+<#
+.SYNOPSIS
+Get an environment variable and unset it
+
+.PARAMETER Name
+The name of the environment variable to read and unset
+
+.PARAMETER Required
+If set, throw FileNotFoundException if the environment variable requested is not
+set
+
+.NOTES
+The purpose of the function is to get and scrub off the password passed as an
+env var in one go. To preserve the env var, use `GetEnvironmentVariable()`
+directly.
+#>
+function FetchEnv ([string]$Name, [bool]$Required = $false) {
+	$RetVal = [Environment]::GetEnvironmentVariable($Name)
+	[Environment]::SetEnvironmentVariable($Name, '')
+	if ( $RetVal ) {
+		return $RetVal
+	}
+	else {
+		if ($Required) {
+			throw New-Object IO.FileNotFoundException ("${Name}: unset env var")
+		}
+		else {
+			return $null
+		}
+	}
+}
+
+<#
+.SYNOPSIS
+Read data from STDIN until EOF and return data as decoded string
+#>
+function ExhaustStdin () {
+	$stream = New-Object IO.StreamReader ( [Console]::OpenStandardInput() )
+	return $stream.ReadToEnd()
+}
+
+
+######################################################################
+# Execution starts here
+######################################################################
+
+# Compose a message
+$mail = New-Object Mail.MailMessage (
+	(FetchEnv "mail_from" $true),
+	(FetchEnv "mail_to" $true),
+	(FetchEnv "mail_subject" $true),
+	(ExhaustStdin)) # This is the part where the mail body is read from STDIN
+
+# Add attachments
+foreach ($file in $args) {
+	[string]$file = $file
+
+	$a = New-Object Mail.Attachment (
+		$file,
+		# Treat all attachments as binary
+		[System.Net.Mime.MediaTypeNames+Application]::Octet)
+	# Timestamp support
+	$a.ContentDisposition.CreationDate = [IO.File]::GetCreationTime($file)
+	$a.ContentDisposition.ModificationDate = [IO.File]::GetLastWriteTime($file)
+	$a.ContentDisposition.ReadDate = [IO.File]::GetLastAccessTime($file)
+
+	$mail.Attachments.Add($a)
+}
+
+# Set up credentials
+$client_cred = New-Object NetworkCredential (
+	(FetchEnv "smtp_username"),
+	(FetchEnv "smtp_password"))
+
+# Set up client TLS cert
+$tls_cert = FetchEnv("smtp_tls_cert")
+if ($null -ne $tls_cert) {
+	$cert_chain = New-Object X509Certificates.X509Certificate ( $tls_cert )
+}
+else {
+	$cert_chain = $null
+}
+
+# Read target SMTP host
+$smtp_host = FetchEnv "smtp_host"
+if (!$smtp_host) {
+	$smtp_host = "localhost"
+}
+
+# Set up SMTP client object
+$smtp = New-Object Mail.SmtpClient ($smtp_host)
+if ($cert_chain) {
+	$smtp.ClientCertificates.Add($cert_chain)
+}
+$smtp.Credentials = $client_cred
+$smtp_port = FetchEnv "smtp_port"
+if ($smtp_port) {
+	$smtp.Port = [int]$smtp_port
+}
+
+$tlsmode = FetchEnv "smtp_tls"
+if (!$tlsmode) {
+	# Determine the "tlsmode" to default to
+	if ($smtp_host -eq "localhost") {
+		# No need to waste computing power on TLS.
+		# Unless you're paranoid and don't trust the hosts file.
+		$tlsmode = "N"
+	}
+	else {
+		# Transmitting plain text data on the internet nowadays is no-brainer.
+		# Most email services will refuse anyway.
+		$tlsmode = "F"
+	}
+}
+
+# Set `$smtp.EnableSsl` based on `$tlsmode`
+if ($tlsmode -eq "F" -or $tlsmode -eq "O") {
+	$smtp.EnableSsl = $true
+}
+elseif ($tlsmode -eq "N") {
+	$smtp.EnableSsl = $false
+}
+
+try {
+	$smtp.Send($mail)
+}
+catch {
+	if ($tlsmode -eq "O") {
+		# Opportunistic tlsmode. Try again with TLS disabled.
+		# Please think twice and fix the problem before resorting to this bit.
+		$smtp.EnableSsl = $false
+		$smtp.Send($mail)
+	}
+	else {
+		# Let the script die
+		throw $_
+	}
+}