chiark / gitweb /
wip, and move PacketQueue
[hippotat.git] / server
diff --git a/server b/server
index fcf7a81f5ed87e3dc13d05d5192adb08c92a0857..db13f25954d01ff4ad24fe6fbd6bb4305e0d2995 100755 (executable)
--- a/server
+++ b/server
-#!/usr/bin/python2
+#!/usr/bin/python3
 
-from twisted.web.server import Site
-from twisted.web.resource import Resource
+import signal
+signal.signal(signal.SIGINT, signal.SIG_DFL)
+
+import sys
+import os
+
+import twisted.internet
+import twisted.internet.endpoints
 from twisted.web.server import NOT_DONE_YET
-from twisted.internet import reactor
+from twisted.logger import LogLevel
+
+#import twisted.web.server import Site
+#from twisted.web.resource import Resource
+
+from optparse import OptionParser
+from configparser import ConfigParser
+from configparser import NoOptionError
 
-import ConfigParser
+import collections
 
-import cgi
+import syslog
+
+from hippotat import *
 
 clients = { }
 
-def ipaddress(input):
-  try:
-    r = IPv4Address(input)
-  except AddressValueError:
-    r = IPv6Address(input)
-  return r
+defcfg = '''
+[DEFAULT]
+max_batch_down = 65536
+max_queue_time = 10
+max_request_time = 54
+target_requests_outstanding = 3
 
-def ipnetwork(input):
-  try:
-    r = IPv4Network(input)
-  except NetworkValueError:
-    r = IPv6Network(input)
-  return r
+[virtual]
+mtu = 1500
+# network
+# [host]
+# [relay]
+
+[server]
+ipif = userv root ipif %(host)s,%(relay)s,%(mtu)s,slip %(network)s
+addrs = 127.0.0.1 ::1
+port = 8099
+
+[limits]
+max_batch_down = 262144
+max_queue_time = 121
+max_request_time = 121
+target_requests_outstanding = 10
+'''
+
+#---------- error handling ----------
+
+def crash(err):
+  print('CRASH ', err, file=sys.stderr)
+  try: reactor.stop()
+  except twisted.internet.error.ReactorNotRunning: pass
+
+def crash_on_defer(defer):
+  defer.addErrback(lambda err: crash(err))
+
+def crash_on_critical(event):
+  if event.get('log_level') >= LogLevel.critical:
+    crash(twisted.logger.formatEvent(event))
+
+#---------- "router" ----------
+
+def route(packet, saddr, daddr):
+  print('TRACE ', saddr, daddr, packet)
+  try: client = clients[daddr]
+  except KeyError: dclient = None
+  if dclient is not None:
+    dclient.queue_outbound(packet)
+  elif saddr.is_link_local or daddr.is_link_local:
+    log_discard(packet, saddr, daddr, 'link-local')
+  elif daddr == host or daddr not in network:
+    print('TRACE INBOUND ', saddr, daddr, packet)
+    queue_inbound(packet)
+  elif daddr == relay:
+    log_discard(packet, saddr, daddr, 'relay')
+  else:
+    log_discard(packet, saddr, daddr, 'no client')
+
+def log_discard(packet, saddr, daddr, why):
+  print('DROP ', saddr, daddr, why)
+#  syslog.syslog(syslog.LOG_DEBUG,
+#                'discarded packet %s -> %s (%s)' % (saddr, daddr, why))
+
+#---------- client ----------
+
+class Client():
+  def __init__(self, ip, cs):
+    # instance data members
+    self._ip = ip
+    self._cs = cs
+    self.pw = cfg.get(cs, 'password')
+    self._rq = collections.deque() # requests
+    # self._pq = PacketQueue(...)
+    # plus from config:
+    #  .max_batch_down
+    #  .max_queue_time
+    #  .max_request_time
+    #  .target_requests_outstanding
+    for k in ('max_batch_down','max_queue_time','max_request_time',
+              'target_requests_outstanding'):
+      req = cfg.getint(cs, k)
+      limit = cfg.getint('limits',k)
+      self.__dict__[k] = min(req, limit)
+    self._pq = PacketQueue(self.max_queue_time)
+
+    def process_arriving_data(self, d):
+      for packet in slip.decode(d):
+        (saddr, daddr) = packet_addrs(packet)
+        if saddr != self._ip:
+          raise ValueError('wrong source address %s' % saddr)
+        route(packet, saddr, daddr)
+
+    def _req_cancel(self, request):
+      request.finish()
+
+    def _req_error(self, err, request):
+      self._req_cancel(request)
+
+    def queue_outbound(self, packet):
+      self._pq.append(packet)
+
+    def http_request(self, request):
+      request.setHeader('Content-Type','application/octet-stream')
+      reactor.callLater(self.max_request_time, self._req_cancel, request)
+      request.notifyFinish().addErrback(self._req_error, request)
+      self._rq.append(request)
+      self._check_outbound()
+
+    def _check_outbound(self):
+      while True:
+        try: request = self._rq[0]
+        except IndexError: request = None
+        if request and request.finished:
+          self._rq.popleft()
+          continue
+
+        if not self._pq.nonempty():
+          # no packets, oh well
+          continue
 
+        if request is None:
+          # no request
+          break
+
+        # request, and also some non-expired packets
+        while True:
+          packet = self.pq.popleft()
+          if packet is None: break
+
+          encoded = slip.encode(packet)
+          
+          if request.sentLength > 0:
+            if (request.sentLength + len(slip.delimiter)
+                + len(encoded) > self.max_batch_down):
+              break
+            request.write(slip.delimiter)
+
+          request.write(encoded)
+          self._pq.popLeft()
+
+        assert(request.sentLength)
+        self._rq.popLeft()
+        request.finish()
+        # round again, looking for more to do
+
+      while len(self._rq) > self.target_requests_outstanding:
+        request = self._rq.popleft()
+        request.finish()
+
+class IphttpResource(twisted.web.resource.Resource):
+  isLeaf = True
+  def render_POST(self, request):
+    # find client, update config, etc.
+    ci = ipaddr(request.args['i'])
+    c = clients[ci]
+    pw = request.args['pw']
+    if pw != c.pw: raise ValueError('bad password')
+
+    # update config
+    for r, w in (('mbd', 'max_batch_down'),
+                 ('mqt', 'max_queue_time'),
+                 ('mrt', 'max_request_time'),
+                 ('tro', 'target_requests_outstanding')):
+      try: v = request.args[r]
+      except KeyError: continue
+      v = int(v)
+      c.__dict__[w] = v
+
+    try: d = request.args['d']
+    except KeyError: d = ''
+
+    c.process_arriving_data(d)
+    c.new_request(request)
+
+  def render_GET(self, request):
+    return b'<html><body>hippotat</body></html>'
+
+def start_http():
+  resource = IphttpResource()
+  site = twisted.web.server.Site(resource)
+  for addrspec in cfg.get('server','addrs').split():
+    try:
+      addr = ipaddress.IPv4Address(addrspec)
+      endpointfactory = twisted.internet.endpoints.TCP4ServerEndpoint
+    except AddressValueError:
+      addr = ipaddress.IPv6Address(addrspec)
+      endpointfactory = twisted.internet.endpoints.TCP6ServerEndpoint
+    ep = endpointfactory(reactor, cfg.getint('server','port'), addr)
+    crash_on_defer(ep.listen(site))
+
+#---------- config and setup ----------
+        
 def process_cfg():
   global network
-  global ourself
+  global host
+  global relay
+  global ipif_command
+
+  network = ipnetwork(cfg.get('virtual','network'))
+  if network.num_addresses < 3 + 2:
+    raise ValueError('network needs at least 2^3 addresses')
 
-  network = ipnetwork(cfg.get('virtual','network')
   try:
-    ourself = cfg.get('virtual','server')
-  except ConfigParser.NoOptionError:
-    ourself = network.hosts().next()
+    host = cfg.get('virtual','host')
+  except NoOptionError:
+    host = next(network.hosts())
 
-  
+  try:
+    relay = cfg.get('virtual','relay')
+  except NoOptionError:
+    for search in network.hosts():
+      if search == host: continue
+      relay = search
+      break
 
-class Client():
-  def __init__(ip):
-  # instance data members
-  #  ._ip
-    self._ip = IPv4Address(ip)
-    clients 
+  for cs in cfg.sections():
+    if not (':' in cs or '.' in cs): continue
+    ci = ipaddr(cs)
+    if ci not in network:
+      raise ValueError('client %s not in network' % ci)
+    if ci in clients:
+      raise ValueError('multiple client cfg sections for %s' % ci)
+    clients[ci] = Client(ci, cs)
 
-class FormPage(Resource):
-  def render_POST(self, request):
+  global mtu
+  mtu = cfg.get('virtual','mtu')
+
+  iic_vars = { }
+  for k in ('host','relay','mtu','network'):
+    iic_vars[k] = globals()[k]
+
+  ipif_command = cfg.get('server','ipif', vars=iic_vars)
+
+def startup():
+  global cfg
+
+  op = OptionParser()
+  op.add_option('-c', '--config', dest='configfile',
+                default='/etc/hippottd/server.conf')
+  global opts
+  (opts, args) = op.parse_args()
+  if len(args): op.error('no non-option arguments please')
+
+  twisted.logger.globalLogPublisher.addObserver(crash_on_critical)
+
+  cfg = ConfigParser()
+  cfg.read_string(defcfg)
+  cfg.read(opts.configfile)
+  process_cfg()
+
+  start_ipif(ipif_command, route)
+  start_http()
+
+startup()
+reactor.run()
+print('CRASHED (end)', file=sys.stderr)