wait for the burp-server to be up and running while starting the agent

CHANGELOG.rst

@@ -18,6 +18,11 @@ Current
 - Fix: issue `#268 <https://git.ziirish.me/ziirish/burp-ui/issues/268>`_
 - `Full changelog <https://git.ziirish.me/ziirish/burp-ui/compare/0.6.0...master>`__
 
+0.6.6 (04/01/2019)
+------------------
+
+- Fix: agent cannot start `#302 <https://git.ziirish.me/ziirish/burp-ui/issues/302>`__
+
 0.6.5 (03/27/2019)
 ------------------
 

burpui/engines/agent.py

@@ -13,6 +13,7 @@ import sys
 import ssl
 import json
 import logging
+import time
 import trio
 
 from ..exceptions import BUIserverException
@@ -38,6 +39,7 @@ BUI_DEFAULTS = {
         'sslkey': '',
         'backend': 'burp2',
         'password': 'azerty',
+        'init_wait': 15,
     },
 }
 
@@ -50,10 +52,11 @@ class BurpHandler(BUIbackend):
     foreign = BUIbackend.__abstractmethods__
     BUIbackend.__abstractmethods__ = frozenset()
 
-    def __init__(self, backend='burp2', logger=None, conf=None):
+    def __init__(self, backend='burp2', logger=None, conf=None, init_wait=0):
         self.backend_name = backend
         self.is_async = backend == 'parallel'
         self.logger = logger
+        wait = init_wait
 
         top = __name__
         if '.' in self.backend_name:
@@ -70,8 +73,16 @@ class BurpHandler(BUIbackend):
             else:
                 Client = mod.Burp
             self.backend = Client(conf=conf)
-            stats = self.backend.statistics()
-            if 'alive' not in stats or not stats['alive']:
+            def __backend_alive():
+                stats = self.backend.statistics()
+                return 'alive' in stats and stats['alive']
+            alive = __backend_alive()
+            while not alive and wait > 0:
+                self.logger.debug("Waiting for the backend to become alive... {}/{}".format(init_wait - wait, init_wait))
+                time.sleep(1)
+                alive = __backend_alive()
+                wait -= 1
+            if not alive:
                 raise BUIserverException('Cannot talk to burp server')
         except Exception as exc:
             self.logger.error('Failed loading backend {}: {}'.format(self.backend_name, str(exc)), exc_info=exc, stack_info=True)
@@ -117,9 +128,10 @@ class BUIAgent(BUIbackend):
         self.sslcert = self.conf.safe_get('sslcert')
         self.sslkey = self.conf.safe_get('sslkey')
         self.password = self.conf.safe_get('password')
+        self.init_wait = self.conf.safe_get('init_wait', 'integer')
         self.conf.setdefault('BUI_AGENT', True)
 
-        self.client = BurpHandler(self.backend, self.logger, self.conf)
+        self.client = BurpHandler(self.backend, self.logger, self.conf, self.init_wait)
 
     def _ssl_context(self):
         if not self.ssl:

burpui/engines/monitor.py

@@ -206,6 +206,8 @@ class MonitorPool:
                         'server_version': 'unknown',
                         'client_version': 'unknown'
                     }
+                    if self.pool.empty():
+                        await self.fill_pool()
                     while not self.pool.empty():
                         mon = await self.pool.get()
                         tmp.append(mon)

burpui/misc/backend/parallel.py

@@ -224,9 +224,9 @@ class Burp(Burp2):
         if self.init_wait:
             exc = None
             init_mon = Parallel(conf)
-            for _ in range(self.init_wait):
+            for i in range(self.init_wait):
                 try:
-                    self.logger.warning('monitor not ready, waiting for it...')
+                    self.logger.warning('monitor not ready, waiting for it... {}/{}'.format(i, self.init_wait))
                     trio.run(init_mon.conn)
                     if init_mon.connected:
                         break
@@ -237,6 +237,8 @@ class Burp(Burp2):
                 self.logger.error('monitor not ready, giving up!')
                 raise exc
             del init_mon
+        stats = self.statistics()
+        if 'alive' in stats and stats['alive']:
             self.init_all()
 
     def init_all(self):
@@ -262,12 +264,18 @@ class Burp(Burp2):
 
     def get_client_version(self, agent=None):
         if self._client_version is None:
-            self._client_version = trio.run(self._async_request, 'client_version')
+            try:
+                self._client_version = trio.run(self._async_request, 'client_version')
+            except BUIserverException:
+                return ''
         return self._client_version or ''
 
     def get_server_version(self, agent=None):
         if self._server_version is None:
-            self._server_version = trio.run(self._async_request, 'server_version')
+            try:
+                self._server_version = trio.run(self._async_request, 'server_version')
+            except BUIserverException:
+                return ''
         return self._server_version or ''
 
     async def _async_status(self, query='c:\n', timeout=None, cache=True, agent=None):
@@ -285,8 +293,6 @@ class Burp(Burp2):
             return await async_client.request(func, *args, **kwargs)
         except (OSError, IOError) as exc:
             raise BUIserverException(str(exc))
-        if not self._ready:
-            self.init_all()
 
     @usetriorun
     def status(self, query='c:\n', timeout=None, cache=True, agent=None):
@@ -827,6 +833,12 @@ class Burp(Burp2):
 # Make every "Burp" method async
 class AsyncBurp(Burp):
 
+    @property
+    async def batch_list_supported(self):
+        if self._batch_list_supported is None:
+            self._batch_list_supported = json.loads(await self._async_request('batch_list_supported'))
+        return self._batch_list_supported
+
     # this method must not be async!
     @implement
     def statistics(self, agent=None):
@@ -877,6 +889,17 @@ class AsyncBurp(Burp):
         """
         return await self._async_get_all_clients()
 
+    @implement
+    async def get_attr(self, name, default=None, agent=None):
+        """See :func:`burpui.misc.backend.interface.BUIbackend.get_attr`"""
+        try:
+            try:
+                return await getattr(self, name, default)
+            except TypeError:
+                return getattr(self, name, default)
+        except AttributeError:
+            return default
+
     def __getattribute__(self, name):
         if name in BUIBACKEND_INTERFACE_METHODS or name in ['_guess_os']:
             wrap = False

burpui/misc/backend/utils/burp2.py

@@ -129,14 +129,20 @@ class Monitor(object):
     @property
     def server_version(self):
         if self._server_version is None:
-            self.status()
+            try:
+                self.status()
+            except BUIserverException:
+                return ''
         return self._server_version or ''
 
     @property
     def alive(self):
         # clients may be idle for some time, in that case we may need to start them again
         if not self._proc_is_alive():
-            self._spawn_burp()
+            try:
+                self._spawn_burp()
+            except OSError:
+                pass
         return self._proc_is_alive()
 
     def _exit(self):

docs/buiagent.rst

@@ -113,6 +113,9 @@ section as below:
     version = 1
     # agent password
     password = password
+    # time to wait at startup
+    # the burp server must be started before your agent
+    init_wait = 15
 
 
 Each option is commented, but here is a more detailed documentation:
@@ -125,6 +128,8 @@ Each option is commented, but here is a more detailed documentation:
 - *version*: What version of `Burp`_ this `bui-agent`_ instance manages. (see
   `Burp-UI versions <advanced_usage.html#versions>`__ for more details)
 - *password*: The shared secret between the `Burp-UI`_ server and `bui-agent`_.
+- *init_wait*: The time to wait for the backend to be alive (this is useful in
+  case you start every services at the same time).
 
 As with `Burp-UI`_, you need a specific ``[Burp]`` section.
 Please refer to the `Burp-UI versions <advanced_usage.html#options>`__

docs/upgrading.rst

@@ -31,6 +31,11 @@ v0.7.0
   ``:AUTH`` suffix (so ``BASIC`` becomes ``BASIC:AUTH``, etc.).
   Please make sure you rename those sections accordingly so you won't be locked
   out.
+- **Breaking** - the ``bui-agent`` will now exit when its *system* requirements
+  are not met at startup time (that is: the burp-server must be up and running
+  and the burp-client used by burp-ui must be able to reach the burp-server).
+  A new timeout has been added though in order for ``bui-agent`` to wait for the
+  burp-server to be ready.
 
 v0.6.0
 ------

share/burpui/etc/buiagent.sample.cfg

@@ -18,6 +18,9 @@ sslkey = /var/lib/burp/ssl/server/ssl_cert-server.key
 backend = burp2
 # agent password
 password = azerty
+# time to wait at startup
+# the burp server must be started before your agent
+init_wait = 15
 
 [Security]
 ## This section contains some security options. Make sure you understand the