#!/bin/bash
set -e
# Variables
WEBROOT="/var/www/html/markdown"
CGI_DIR="$WEBROOT/cgi-bin"
MD_DIR="$WEBROOT/md"
APACHE_CONF="/etc/apache2/sites-available/markdown.conf"
SCRIPT_NAME="render.py"
SCRIPT_PATH="$CGI_DIR/$SCRIPT_NAME"
echo "==> Installing dependencies..."
sudo apt update
sudo apt install -y apache2 python3 python3-markdown
echo "==> Enabling CGI module..."
sudo a2enmod cgi
echo "==> Creating directory structure..."
sudo mkdir -p "$CGI_DIR"
sudo mkdir -p "$MD_DIR/docs"
echo "==> Writing secure CGI Python script with nested directory support..."
sudo tee "$SCRIPT_PATH" > /dev/null << 'EOF'
#!/usr/bin/env python3
import cgi
import os
import markdown
import html
print("Content-Type: text/html\n")
form = cgi.FieldStorage()
filename = form.getvalue("file", "index.md")
# Reject malicious input
if not filename or ".." in filename or filename.startswith("/"):
print("Status: 400 Bad Request\n")
print("400 Bad Request
Invalid filename.
")
exit()
# Resolve safe absolute path
basedir = os.path.abspath("../md")
requested_path = os.path.normpath(os.path.join(basedir, filename))
if not requested_path.startswith(basedir):
print("Status: 403 Forbidden\n")
print("403 Forbidden
Access denied.
")
exit()
# Check existence
if not os.path.isfile(requested_path):
print("Status: 404 Not Found\n")
print(f"404 Not Found
{html.escape(filename)} not found.
")
exit()
# Read and convert
with open(requested_path, 'r') as f:
md_text = f.read()
html_content = markdown.markdown(md_text)
print(f"""
{html.escape(filename)}
{html.escape(filename)}
{html_content}
""")
EOF
echo "==> Making script executable..."
sudo chmod +x "$SCRIPT_PATH"
echo "==> Creating example markdown files..."
sudo tee "$MD_DIR/index.md" > /dev/null << EOF
# Welcome
This is the **root index** page.
EOF
sudo tee "$MD_DIR/docs/tutorial.md" > /dev/null << EOF
# Tutorial Page
This is a **nested Markdown file** inside `docs/`.
EOF
echo "==> Creating Apache virtual host config..."
sudo tee "$APACHE_CONF" > /dev/null << EOF
ServerAdmin webmaster@localhost
DocumentRoot $WEBROOT
Options +ExecCGI
AddHandler cgi-script .py
Require all granted
Alias /markdown/ $WEBROOT/
EOF
echo "==> Enabling site and restarting Apache..."
sudo a2ensite markdown
sudo systemctl reload apache2
echo ""
echo "✅ Setup Complete!"
echo "Open in your browser:"
echo " Root file: http://localhost/cgi-bin/render.py?file=index.md"
echo " Nested file: http://localhost/cgi-bin/render.py?file=docs/tutorial.md"