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{"error":{"code":401,"message":"There is an error"}}

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#!/usr/bin/env python3
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from flask import Flask, request, render_template, jsonify, abort, redirect, session
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import uuid
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import os
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from datetime import datetime, timedelta
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import hashlib
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app = Flask(__name__)
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server_start_time = datetime.now()
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server_start_str = server_start_time.strftime(‘%Y%m%d%H%M%S’)
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secure_key = hashlib.sha256(f’secret_key_{server_start_str}’.encode()).hexdigest()
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app.secret_key = secure_key
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app.config[‘PERMANENT_SESSION_LIFETIME’] = timedelta(seconds=300)
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flag = os.environ.get(‘FLAG’, “flag{this_is_a_fake_flag}”)
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secret = uuid.UUID(‘31333337–1337–1337–1337–133713371337’)
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def is_safe_username(username):
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 “””Check if the username is alphanumeric and less than 20 characters.”””
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 return username.isalnum() and len(username) < 20
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[@app](http://twitter.com/app "Twitter profile for @app").route(‘/’, methods=[‘GET’, ‘POST’])
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def main():
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 “””Handle the main page where the user submits their username.”””
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 if request.method == ‘GET’:
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 return render_template(‘index.html’)
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 elif request.method == ‘POST’:
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 username = request.values[‘username’]
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 password = request.values[‘password’]
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 if not is_safe_username(username):
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 return render_template(‘index.html’, error=’Invalid username’)
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 if not password:
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 return render_template(‘index.html’, error=’Invalid password’)
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 if username.lower().startswith(‘admin’):
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 return render_template(‘index.html’, error=’Don\’t try to impersonate administrator!’)
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 if not username or not password:
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 return render_template(‘index.html’, error=’Invalid username or password’)
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 uid = uuid.uuid5(secret, username)
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 session[‘username’] = username
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 session[‘uid’] = str(uid)
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 return redirect(f’/user/{uid}’)
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[@app](http://twitter.com/app "Twitter profile for @app").route(‘/user/’)
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def user_page(uid):
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 “””Display the user’s session page based on their UUID.”””
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 try:
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 uid = uuid.UUID(uid)
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 except ValueError:
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 abort(404)
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 session[‘is_admin’] = False
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 return ‘Welcome Guest! Sadly, you are not admin and cannot view the flag.’
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[@app](http://twitter.com/app "Twitter profile for @app").route(‘/admin’)
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def admin_page():
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 “””Display the admin page if the user is an admin.”””
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 if session.get(‘is_admin’) and uuid.uuid5(secret, ‘administrator’) and session.get(‘username’) == ‘administrator’:
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 return flag
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 else:
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 abort(401)
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[@app](http://twitter.com/app "Twitter profile for @app").route(‘/status’)
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def status():
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 current_time = datetime.now()
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 uptime = current_time — server_start_time
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 formatted_uptime = str(uptime).split(‘.’)[0]
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 formatted_current_time = current_time.strftime(‘%Y-%m-%d %H:%M:%S’)
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 status_content = f”””Server uptime: {formatted_uptime}
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 Server time: {formatted_current_time}
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 “””
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 return status_content
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if __name__ == ‘__main__’:
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 app.run(“0.0.0.0”, port=9999)

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if session.get('is_admin') and uuid.uuid5(secret, 'administrator') and session.get('username') == 'administrator':
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        return flag
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    else:
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        abort(401)

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import uuid
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# this is provided in code.
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secret = uuid.UUID('31333337-1337-1337-1337-133713371337')
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print(secret)

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import hashlib
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 import uuid
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secure_key = hashlib.sha256(f'secret_key_20240922172016'.encode()).hexdigest()
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 print(secure_key)

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flask-unsign --sign --cookie "{'is_admin': True, 'uid': '02ec19dc-bb01-5942-a640-7099cda78081', 'username': 'administrator'}" --secret 'a45bb96b977c34872488db6f2a041a7633a849871fc06432d70fbfba4aa30328'