dnsmasq.leases based updater

Also a self-claim module

at.py

@@ -7,15 +7,22 @@ import traceback
 from datetime import datetime
 from wsgiref import simple_server
 from pesto import Response, dispatcher_app
+from pesto.session import session_middleware
+from pesto.session.memorysessionmanager import MemorySessionManager
 from time import sleep, time
 from collections import namedtuple
 from jinja2 import Environment, FileSystemLoader 
+from urllib import urlencode
+from hashlib import sha256
 
 import config
 
 dispatcher = dispatcher_app()
+app = session_middleware(MemorySessionManager())(dispatcher)
 logger = logging.getLogger()
-env = Environment(loader=FileSystemLoader('templates'))
+env = Environment(loader=FileSystemLoader('templates'),
+    autoescape='html',
+    extensions=['jinja2.ext.autoescape'])
 conn = None
 updater = None
 
@@ -30,6 +37,17 @@ def render(filepath):
         return func
     return decorator
 
+def restrict_ip(prefix='', exclude=[], fail_response=Response(status=403)):
+    def decorator(f):
+        @wraps(f)
+        def func(request, *a, **kw):
+            r_addr = request.remote_addr
+            if not r_addr.startswith(prefix) or r_addr in exclude:
+                return fail_response
+            return f(request, *a, **kw)
+        return func
+    return decorator
+
 def strfts(ts, format='%d/%m/%Y %H:%M'):
     return datetime.fromtimestamp(ts).strftime(format)
 env.filters['strfts'] = strfts
@@ -37,6 +55,7 @@ env.filters['strfts'] = strfts
 def setup_db():
     conn = sqlite3.connect(config.db)
     conn.row_factory = sqlite3.Row
+    conn.isolation_level = None # for autocommit mode
     return conn
 
 DeviceInfo = namedtuple('DeviceInfo', ['hwaddr', 'owner', 'ignored'])
@@ -55,15 +74,14 @@ def get_device_infos(conn, hwaddrs):
         yield DeviceInfo(row['hwaddr'], owner, ignored)
 
 class Updater(threading.Thread):
-    def __init__(self, cap_file, timeout, *a, **kw):
-        self.cap_file = cap_file
+    def __init__(self,  timeout, *a, **kw):
         self.timeout = timeout
         self.lock = threading.Lock()
         self.active = {}
         threading.Thread.__init__(self, *a, **kw)
     def purge_stale(self):
         now = time()
-        for addr, atime in self.active.items():
+        for addr, (atime, ip, name) in self.active.items():
             if now - atime > self.timeout:
                 del self.active[addr]
     def get_active_devices(self):
@@ -72,38 +90,166 @@ class Updater(threading.Thread):
         r = dict(self.active)
         self.lock.release()
         return r
-    def update(self, hwaddr):
+    def get_device(self, ip):
+        for hwaddr, (atime, dip, name) in \
+            self.get_active_devices().iteritems():
+            if ip == dip:
+                return hwaddr, name
+    def update(self, hwaddr, atime = None, ip = None, name = None):
+        atime = atime or time()
         self.lock.acquire()
-        self.active[hwaddr] = time()
+        self.active[hwaddr] = (atime, ip, name)
         self.lock.release()
+        logger.info('updated %s with atime %s and ip %s',
+            hwaddr, strfts(atime), ip)
+
+class CapUpdater(Updater):
+    def __init__(self, cap_file, *a, **kw):
+        self.cap_file = cap_file
+        Updater.__init__(self, *a, **kw)
     def run(self):
         while True:
             try:
-                f = open(self.cap_file, 'r', buffering=0)
-                logger.info('Updater ready on cap file %s', self.cap_file)
-                while True:
-                    hwaddr = f.readline().strip()
-                    if not hwaddr:
-                        break
-                    self.update(hwaddr)
-                    logger.info('logged dhcp request from %s', hwaddr)
+                with open(self.cap_file, 'r', buffering=0) as f:
+                    logger.info('Updater ready on cap file %s', self.cap_file)
+                    while True:
+                        hwaddr = f.readline().strip()
+                        if not hwaddr:
+                            break
+                        self.update(hwaddr)
                 logging.warning('Cap file %s closed, reopening', self.cap_file)
             except Exception as e:
                 logging.error('Updater got an exception:\n' + \
                     traceback.format_exc(e))
                 sleep(10.0)
 
+class DnsmasqUpdater(Updater):
+    def __init__(self, lease_file, lease_offset, *a, **kw):
+        self.lease_file = lease_file
+        self.lease_offset = lease_offset
+        self.last_modified = 0
+        Updater.__init__(self, *a, **kw)
+    def run(self):
+        import os
+        while True:
+            try:
+                mtime = os.stat(self.lease_file).st_mtime
+                if mtime > self.last_modified:
+                    logger.info('Lease file changed, updating')
+                    with open(self.lease_file, 'r') as f:
+                        for line in f:
+                            ts, hwaddr, ip, name, client_id = line.split(' ')
+                            self.update(hwaddr, int(ts) - self.lease_offset, ip, name)
+                self.last_modified = mtime
+                sleep(3.0)
+            except Exception as e:
+                logging.error('Updater got an exception:\n' + \
+                    traceback.format_exc(e))
+                sleep(10.0)
+                
+
 @dispatcher.match('/', 'GET')
 @render('main.html')
 def now_at(request):
     devices = updater.get_active_devices()
     device_infos = list(get_device_infos(conn, devices.keys()))
     device_infos.sort(key=lambda di: devices.__getitem__)
-    users = list(dict((info.owner, devices[info.hwaddr]) for info in device_infos 
+    users = list(dict((info.owner, devices[info.hwaddr][0]) for info in device_infos 
         if info.owner and not info.ignored).iteritems())
     users.sort(key=lambda (u, a): a, reverse=True)
     unknown = set(devices.keys()) - set(d.hwaddr for d in device_infos)
-    return dict(users=users, unknown=unknown)
+    return dict(users=users, unknown=unknown, login=request.session.get('login'))
+
+restrict_to_hs = restrict_ip(prefix=config.claimable_prefix, 
+    exclude=config.claimable_exclude)
+
+@dispatcher.match('/register', 'GET')
+@restrict_to_hs
+@render('register.html')
+def register_form(request):
+    return request.form
+
+@dispatcher.match('/register', 'POST')
+@restrict_to_hs
+def register(request):
+    login = request['login']
+    url = request['url']
+    if 'wiki' in request.form:
+        url = config.wiki_url % { 'login': login }
+    try:
+        conn.execute('insert into users (login, url, pass) values (?, ?, ?)',
+            [login, url, sha256(request['password']).hexdigest()])
+        return Response.redirect('/')
+    except sqlite3.Error as e:
+        request.form['error'] = 'Cannot add user - username taken?'
+        return register_form(request)
+
+@dispatcher.match('/login', 'GET')
+@restrict_to_hs
+@render('login.html')
+def login_form(request):
+    return request.form
+
+def get_credentials(login, password):
+    row = conn.execute('select userid from users where login = ? and pass = ?',
+        [login, sha256(password).hexdigest()]).fetchone()
+    return row and row['userid']
+
+@dispatcher.match('/login', 'POST')
+@restrict_to_hs
+def login(request):
+    login = request.get('login')
+    pwd = request.get('password')
+    goto = request.get('goto') or '/'
+    userid = get_credentials(login, pwd)
+    if userid:
+        request.session['userid'] = userid
+        request.session['login'] = login
+        return Response.redirect(goto)
+    else:
+        request.form['error'] = 'Username or password invalid'
+        return login_form(request)
+
+@dispatcher.match('/logout', 'GET')
+@restrict_to_hs
+def logout(request):
+    request.session.clear()
+    return Response.redirect('/')
+
+def login_required(f):
+    @wraps(f)
+    def func(request, *a, **kw):
+        if 'userid' not in request.session:
+            return Response.redirect('/login?' + 
+                urlencode({'goto': request.path_info,
+                    'error': 'You must log in to continue'}))
+        return f(request, *a, **kw)
+    return func
+
+@dispatcher.match('/claim', 'GET')
+@restrict_to_hs
+@login_required
+@render('claim.html')
+def claim_form(request):
+    hwaddr, name = updater.get_device(request.remote_addr)
+    return { 'hwaddr': hwaddr, 'name': name, 
+        'login': request.session['login'] }
+
+@dispatcher.match('/claim', 'POST')
+@restrict_to_hs
+@login_required
+@render('post_claim.html')
+def claim(request):
+    hwaddr, lease_name = updater.get_device(request.remote_addr)
+    if not hwaddr:
+        return { 'error': 'Invalid device.' }
+    userid = request.session['userid']
+    try:
+        conn.execute('insert into devices (hwaddr, name, owner, ignored)\
+            values (?, ?, ?, ?)', [hwaddr, request['name'], userid, False])
+        return {}
+    except sqlite3.Error as e:
+        return { 'error': 'Could not add device! Perhaps someone claimed it?' }
 
 port = 8080
 if __name__ == '__main__':
@@ -111,7 +257,7 @@ if __name__ == '__main__':
     logger.setLevel(logging.DEBUG)
     logger.addHandler(logging.StreamHandler())
     conn = setup_db()
-    updater = Updater(config.cap_file, config.timeout)
+    updater = DnsmasqUpdater(config.lease_file, config.lease_offset, config.timeout)
     updater.start()
-    server = simple_server.make_server('', port, dispatcher)
+    server = simple_server.make_server('', port, app)
     server.serve_forever()

config.py

@@ -1,4 +1,12 @@
 db = './at.db'
 cap_file = './dhcp-cap'
+lease_file = './leases'
+lease_offset = 60 * 20
 timeout = 300
 
+wiki_url = 'http://hackerspace.pl/wiki/doku.php?id=people:%(login)s:start'
+
+claimable_prefix = ''
+claimable_exclude = [
+#    '127.0.0.1',
+]

templates/claim.html

@@ -0,0 +1,14 @@
+<html>
+<body>
+{% if not hwaddr %}
+<p class="error">Unknown MAC. Are you sure you're in the hackerspace?</p>
+{% else %}
+You are about to claim {{ hwaddr }} as {{ login }}. Do you wish to continue?
+<form action="" method="post">
+<label>Device name (optional):<input type="text" name="name" value="{{ name }}"></label>
+<input type="submit" value="yes">
+</form>
+<a href="/"><button>no</button></button>
+{% endif %}
+</body>
+</html>

templates/login.html

@@ -0,0 +1,13 @@
+<html>
+<body>
+<p class="error">{{ error }}</p>
+<form action="" method="POST">
+<label>login<input type="text" name="login" value="{{ login }}"></label>
+<label>password<input type="password" name="password"></label>
+{% if goto %}
+<input type="hidden" name="goto" value="{{ goto }}">
+{% endif %}
+<input type="submit" value="login"></input>
+</form>
+</body>
+</html>

templates/main.html

@@ -1,4 +1,12 @@
 <html>
+<body>
+<div class="login">
+{% if login %}
+logged in as {{ login }} | <a href="logout">log out</a>
+{% else %}
+<a href="login">login</a> | <a href="register">register</a>
+{% endif %}
+</div>
 Recently at <a href="http://www.hackerspace.pl">hackerspace</a>:
 <ul>
 {% for user, timestamp in users %}
@@ -10,5 +18,6 @@ Recently at <a href="http://www.hackerspace.pl">hackerspace</a>:
 {% endfor %}
 </ul>
 <hr>
-There are {{ unknown|length }} unknown devices operating.
+There are {{ unknown|length }} unknown devices operating. <a href="claim">Claim this device!</a>
+</body>
 </html>

templates/post_claim.html

@@ -0,0 +1,10 @@
+<html>
+<body>
+{% if error %}
+<p class="error">{{ error }}</p>
+{% else %}
+Congratulations, you just claimed this device!
+<a href="/">go back</a>
+{% endif %}
+</body>
+</html>

templates/register.html

@@ -0,0 +1,14 @@
+<html>
+<body>
+<p class="error">{{ error }}</p>
+<form action="" method="POST">
+<label>login<input type="text" name="login" value="{{ login }}"></label>
+<label>password<input type="password" name="password"></label>
+<label>confirm password<input type="password" name="password2"></label>
+<label>homepage url<input type="text" name="url" value="{{ url }}"></label>
+<label>use wiki page as url<input type="checkbox" name="wiki" 
+  value="yes" {% if wiki == 'yes' %}checked="yes"{% endif %}></label>
+<input type="submit" value="register"></input>
+</form>
+</body>
+</html>