core-extra/daemon/core/broker.py

1169 lines
43 KiB
Python

"""
Broker class that is part of the session object. Handles distributing parts of the emulation out to
other emulation servers. The broker is consulted when handling messages to determine if messages
should be handled locally or forwarded on to another emulation server.
"""
import os
import select
import socket
import threading
from core import logger
from core.api import coreapi
from core.conf import ConfigurableManager
from core.coreobj import PyCoreNet
from core.coreobj import PyCoreNode
from core.enumerations import ConfigDataTypes
from core.enumerations import ConfigFlags
from core.enumerations import ConfigTlvs
from core.enumerations import EventTlvs
from core.enumerations import EventTypes
from core.enumerations import ExecuteTlvs
from core.enumerations import FileTlvs
from core.enumerations import LinkTlvs
from core.enumerations import MessageFlags
from core.enumerations import MessageTypes
from core.enumerations import NodeTlvs
from core.enumerations import NodeTypes
from core.enumerations import RegisterTlvs
from core.misc import nodeutils
from core.misc.ipaddress import IpAddress
from core.netns.vif import GreTap
from core.netns.vnet import GreTapBridge
from core.phys.pnodes import PhysicalNode
class CoreDistributedServer(object):
"""
Represents CORE daemon servers for communication.
"""
def __init__(self, name, host, port):
"""
Creates a CoreServer instance.
:param str name: name of the CORE server
:param str host: server address
:param int port: server port
"""
self.name = name
self.host = host
self.port = port
self.sock = None
self.instantiation_complete = False
def connect(self):
"""
Connect to CORE server and save connection.
:return: nothing
"""
assert self.sock is None
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
sock.connect((self.host, self.port))
except IOError as e:
sock.close()
raise e
self.sock = sock
def close(self):
"""
Close connection with CORE server.
:return: nothing
"""
if self.sock is not None:
self.sock.close()
self.sock = None
class CoreBroker(ConfigurableManager):
"""
Helps with brokering messages between CORE daemon servers.
"""
# configurable manager name
name = "broker"
# configurable manager type
config_type = RegisterTlvs.UTILITY.value
def __init__(self, session):
"""
Creates a CoreBroker instance.
:param core.session.Session session: session this manager is tied to
:return: nothing
"""
ConfigurableManager.__init__(self)
self.session = session
self.session_clients = []
self.session_id_master = None
self.myip = None
# dict containing tuples of (host, port, sock)
self.servers = {}
self.servers_lock = threading.Lock()
self.addserver("localhost", None, None)
# dict containing node number to server name mapping
self.nodemap = {}
# this lock also protects self.nodecounts
self.nodemap_lock = threading.Lock()
# reference counts of nodes on servers
self.nodecounts = {}
# set of node numbers that are link-layer nodes (networks)
self.network_nodes = set()
# set of node numbers that are PhysicalNode nodes
self.physical_nodes = set()
# allows for other message handlers to process API messages (e.g. EMANE)
self.handlers = set()
self.handlers.add(self.handle_distributed)
# dict with tunnel key to tunnel device mapping
self.tunnels = {}
self.dorecvloop = False
self.recvthread = None
self.bootcount = 0
def startup(self):
"""
Build tunnels between network-layer nodes now that all node
and link information has been received; called when session
enters the instantation state.
"""
self.addnettunnels()
self.writeservers()
def shutdown(self):
"""
Close all active sockets; called when the session enters the
data collect state
"""
with self.servers_lock:
while len(self.servers) > 0:
name, server = self.servers.popitem()
if server.sock is not None:
logger.info("closing connection with %s @ %s:%s" %
(name, server.host, server.port))
server.close()
self.reset()
self.dorecvloop = False
if self.recvthread is not None:
self.recvthread.join()
def reset(self):
"""
Reset to initial state.
"""
logger.info("broker reset")
self.nodemap_lock.acquire()
self.nodemap.clear()
for server, count in self.nodecounts.iteritems():
if count < 1:
self.delserver(server)
self.nodecounts.clear()
self.bootcount = 0
self.nodemap_lock.release()
self.network_nodes.clear()
self.physical_nodes.clear()
while len(self.tunnels) > 0:
key, gt = self.tunnels.popitem()
gt.shutdown()
def startrecvloop(self):
"""
Spawn the receive loop for receiving messages.
"""
if self.recvthread is not None:
logger.info("server receive loop already started")
if self.recvthread.isAlive():
return
else:
self.recvthread.join()
# start reading data from connected sockets
logger.info("starting server receive loop")
self.dorecvloop = True
self.recvthread = threading.Thread(target=self.recvloop)
self.recvthread.daemon = True
self.recvthread.start()
def recvloop(self):
"""
Receive loop for receiving messages from server sockets.
"""
self.dorecvloop = True
# note: this loop continues after emulation is stopped,
# even with 0 servers
while self.dorecvloop:
rlist = []
with self.servers_lock:
# build a socket list for select call
for server in self.servers.itervalues():
if server.sock is not None:
rlist.append(server.sock)
r, w, x = select.select(rlist, [], [], 1.0)
for sock in r:
server = self.getserverbysock(sock)
logger.info("attempting to receive from server: peer:%s remote:%s",
server.sock.getpeername(), server.sock.getsockname())
if server is None:
# servers may have changed; loop again
continue
rcvlen = self.recv(server)
if rcvlen == 0:
logger.info("connection with %s @ %s:%s has closed" % (
server.name, server.host, server.port))
def recv(self, server):
"""
Receive data on an emulation server socket and broadcast it to
all connected session handlers. Returns the length of data recevied
and forwarded. Return value of zero indicates the socket has closed
and should be removed from the self.servers dict.
:param CoreDistributedServer server: server to receive from
:return: message length
:rtype: int
"""
msghdr = server.sock.recv(coreapi.CoreMessage.header_len)
if len(msghdr) == 0:
# server disconnected
logger.info("server disconnected, closing server")
server.close()
return 0
if len(msghdr) != coreapi.CoreMessage.header_len:
logger.info("warning: broker received not enough data len=%s" % len(msghdr))
return len(msghdr)
msgtype, msgflags, msglen = coreapi.CoreMessage.unpack_header(msghdr)
msgdata = server.sock.recv(msglen)
data = msghdr + msgdata
count = None
logger.info("received message type: %s", MessageTypes(msgtype))
# snoop exec response for remote interactive TTYs
if msgtype == MessageTypes.EXECUTE.value and msgflags & MessageFlags.TTY.value:
data = self.fixupremotetty(msghdr, msgdata, server.host)
logger.info("created remote tty message: %s", data)
elif msgtype == MessageTypes.NODE.value:
# snoop node delete response to decrement node counts
if msgflags & MessageFlags.DELETE.value:
msg = coreapi.CoreNodeMessage(msgflags, msghdr, msgdata)
nodenum = msg.get_tlv(NodeTlvs.NUMBER.value)
if nodenum is not None:
count = self.delnodemap(server, nodenum)
elif msgtype == MessageTypes.LINK.value:
# this allows green link lines for remote WLANs
msg = coreapi.CoreLinkMessage(msgflags, msghdr, msgdata)
self.session.sdt.handle_distributed(msg)
elif msgtype == MessageTypes.EVENT.value:
msg = coreapi.CoreEventMessage(msgflags, msghdr, msgdata)
eventtype = msg.get_tlv(EventTlvs.TYPE.value)
if eventtype == EventTypes.INSTANTIATION_COMPLETE.value:
server.instantiation_complete = True
if self.instantiation_complete():
self.session.check_runtime()
else:
logger.error("unknown message type received: %s", msgtype)
try:
for session_client in self.session_clients:
session_client.sendall(data)
except IOError:
logger.exception("error sending message")
if count is not None and count < 1:
return 0
else:
return len(data)
def addserver(self, name, host, port):
"""
Add a new server, and try to connect to it. If we"re already connected to this
(host, port), then leave it alone. When host,port is None, do not try to connect.
:param str name: name of server
:param str host: server address
:param int port: server port
:return: nothing
"""
with self.servers_lock:
server = self.servers.get(name)
if server is not None:
if host == server.host and port == server.port and \
server.sock is not None:
# leave this socket connected
return
logger.info("closing connection with %s @ %s:%s" % (name, server.host, server.port))
server.close()
del self.servers[name]
logger.info("adding server: %s @ %s:%s" % (name, host, port))
server = CoreDistributedServer(name, host, port)
if host is not None and port is not None:
try:
server.connect()
except IOError:
logger.exception("error connecting to server %s:%s" % (host, port))
if server.sock is not None:
self.startrecvloop()
self.servers[name] = server
def delserver(self, server):
"""
Remove a server and hang up any connection.
:param CoreDistributedServer server: server to delete
:return: nothing
"""
with self.servers_lock:
try:
s = self.servers.pop(server.name)
assert s == server
except KeyError:
logger.exception("error deleting server")
if server.sock is not None:
logger.info("closing connection with %s @ %s:%s" % (server.name, server.host, server.port))
server.close()
def getserverbyname(self, name):
"""
Return the server object having the given name, or None.
:param str name: name of server to retrieve
:return: server for given name
:rtype: CoreDistributedServer
"""
with self.servers_lock:
return self.servers.get(name)
def getserverbysock(self, sock):
"""
Return the server object corresponding to the given socket, or None.
:param sock: socket associated with a server
:return: core server associated wit the socket
:rtype: CoreDistributedServer
"""
with self.servers_lock:
for server in self.servers.itervalues():
if server.sock == sock:
return server
return None
def getservers(self):
"""
Return a list of servers sorted by name.
:return: sorted server list
:rtype: list
"""
with self.servers_lock:
return sorted(self.servers.values(), key=lambda x: x.name)
def getservernames(self):
"""
Return a sorted list of server names (keys from self.servers).
:return: sorted server names
:rtype: list
"""
with self.servers_lock:
return sorted(self.servers.keys())
def tunnelkey(self, n1num, n2num):
"""
Compute a 32-bit key used to uniquely identify a GRE tunnel.
The hash(n1num), hash(n2num) values are used, so node numbers may be
None or string values (used for e.g. "ctrlnet").
:param int n1num: node one id
:param int n2num: node two id
:return: tunnel key for the node pair
:rtype: int
"""
sid = self.session_id_master
if sid is None:
# this is the master session
sid = self.session.session_id
key = (sid << 16) ^ hash(n1num) ^ (hash(n2num) << 8)
return key & 0xFFFFFFFF
def addtunnel(self, remoteip, n1num, n2num, localnum):
"""
Adds a new GreTapBridge between nodes on two different machines.
:param str remoteip: remote address for tunnel
:param int n1num: node one id
:param int n2num: node two id
:param int localnum: local id
:return: nothing
"""
key = self.tunnelkey(n1num, n2num)
if localnum == n2num:
remotenum = n1num
else:
remotenum = n2num
if key in self.tunnels.keys():
logger.warn("tunnel with key %s (%s-%s) already exists!" % (key, n1num, n2num))
else:
objid = key & ((1 << 16) - 1)
logger.info("adding tunnel for %s-%s to %s with key %s", n1num, n2num, remoteip, key)
if localnum in self.physical_nodes:
# no bridge is needed on physical nodes; use the GreTap directly
gt = GreTap(node=None, name=None, session=self.session,
remoteip=remoteip, key=key)
else:
gt = self.session.add_object(cls=GreTapBridge, objid=objid,
policy="ACCEPT", remoteip=remoteip, key=key)
gt.localnum = localnum
gt.remotenum = remotenum
self.tunnels[key] = gt
def addnettunnels(self):
"""
Add GreTaps between network devices on different machines.
The GreTapBridge is not used since that would add an extra bridge.
"""
logger.info("adding network tunnels for nodes: %s", self.network_nodes)
for n in self.network_nodes:
self.addnettunnel(n)
def addnettunnel(self, node_id):
"""
Add network tunnel between node and broker.
:param int node_id: node id of network to add tunnel to
:return: list of gre taps
:rtype: list
"""
try:
net = self.session.get_object(node_id)
logger.info("adding net tunnel for: id(%s) %s", node_id, net)
except KeyError:
raise KeyError("network node %s not found" % node_id)
# add other nets here that do not require tunnels
if nodeutils.is_node(net, NodeTypes.EMANE_NET):
logger.warn("emane network does not require a tunnel")
return None
server_interface = getattr(net, "serverintf", None)
if nodeutils.is_node(net, NodeTypes.CONTROL_NET) and server_interface is not None:
logger.warn("control networks with server interfaces do not need a tunnel")
return None
servers = self.getserversbynode(node_id)
if len(servers) < 2:
logger.warn("not enough servers to create a tunnel: %s", servers)
return None
hosts = []
for server in servers:
if server.host is None:
continue
logger.info("adding server host for net tunnel: %s", server.host)
hosts.append(server.host)
if len(hosts) == 0:
for session_client in self.session_clients:
# get IP address from API message sender (master)
if session_client.client_address != "":
address = session_client.client_address[0]
logger.info("adding session_client host: %s", address)
hosts.append(address)
r = []
for host in hosts:
if self.myip:
# we are the remote emulation server
myip = self.myip
else:
# we are the session master
myip = host
key = self.tunnelkey(node_id, IpAddress.to_int(myip))
if key in self.tunnels.keys():
logger.info("tunnel already exists, returning existing tunnel: %s", key)
gt = self.tunnels[key]
r.append(gt)
continue
logger.info("adding tunnel for net %s to %s with key %s" % (node_id, host, key))
gt = GreTap(node=None, name=None, session=self.session, remoteip=host, key=key)
self.tunnels[key] = gt
r.append(gt)
# attaching to net will later allow gt to be destroyed
# during net.shutdown()
net.attach(gt)
return r
def deltunnel(self, n1num, n2num):
"""
Delete tunnel between nodes.
:param int n1num: node one id
:param int n2num: node two id
:return: nothing
"""
key = self.tunnelkey(n1num, n2num)
try:
logger.info("deleting tunnel between %s - %s with key: %s", n1num, n2num, key)
gt = self.tunnels.pop(key)
except KeyError:
gt = None
if gt:
self.session.delete_object(gt.objid)
del gt
def gettunnel(self, n1num, n2num):
"""
Return the GreTap between two nodes if it exists.
:param int n1num: node one id
:param int n2num: node two id
:return: gre tap between nodes or none
"""
key = self.tunnelkey(n1num, n2num)
logger.info("checking for tunnel(%s) in: %s", key, self.tunnels.keys())
if key in self.tunnels.keys():
return self.tunnels[key]
else:
return None
def addnodemap(self, server, nodenum):
"""
Record a node number to emulation server mapping.
:param CoreDistributedServer server: core server to associate node with
:param int nodenum: node id
:return: nothing
"""
with self.nodemap_lock:
if nodenum in self.nodemap:
if server in self.nodemap[nodenum]:
return
self.nodemap[nodenum].add(server)
else:
self.nodemap[nodenum] = {server}
if server in self.nodecounts:
self.nodecounts[server] += 1
else:
self.nodecounts[server] = 1
def delnodemap(self, server, nodenum):
"""
Remove a node number to emulation server mapping.
Return the number of nodes left on this server.
:param CoreDistributedServer server: server to remove from node map
:param int nodenum: node id
:return: number of nodes left on server
:rtype: int
"""
count = None
with self.nodemap_lock:
if nodenum not in self.nodemap:
return count
self.nodemap[nodenum].remove(server)
if server in self.nodecounts:
count = self.nodecounts[server]
count -= 1
self.nodecounts[server] = count
return count
def getserversbynode(self, nodenum):
"""
Retrieve a set of emulation servers given a node number.
:param int nodenum: node id
:return: core server associated with node
:rtype: set
"""
with self.nodemap_lock:
if nodenum not in self.nodemap:
return set()
return self.nodemap[nodenum]
def addnet(self, nodenum):
"""
Add a node number to the list of link-layer nodes.
:param int nodenum: node id to add
:return: nothing
"""
logger.info("adding net to broker: %s", nodenum)
self.network_nodes.add(nodenum)
logger.info("broker network nodes: %s", self.network_nodes)
def addphys(self, nodenum):
"""
Add a node number to the list of physical nodes.
:param int nodenum: node id to add
:return: nothing
"""
self.physical_nodes.add(nodenum)
def configure_reset(self, config_data):
"""
Ignore reset messages, because node delete responses may still
arrive and require the use of nodecounts.
:param core.conf.ConfigData config_data: configuration data for carrying out a configuration
:return: nothing
"""
return None
def configure_values(self, config_data):
"""
Receive configuration message with a list of server:host:port
combinations that we"ll need to connect with.
:param core.conf.ConfigData config_data: configuration data for carrying out a configuration
:return: nothing
"""
values = config_data.data_values
session_id = config_data.session
if values is None:
logger.info("emulation server data missing")
return None
values = values.split("|")
# string of "server:ip:port,server:ip:port,..."
server_strings = values[0]
server_list = server_strings.split(",")
for server in server_list:
server_items = server.split(":")
(name, host, port) = server_items[:3]
if host == "":
host = None
if port == "":
port = None
else:
port = int(port)
if session_id is not None:
# receive session ID and my IP from master
self.session_id_master = int(session_id.split("|")[0])
self.myip = host
host = None
port = None
# this connects to the server immediately; maybe we should wait
# or spin off a new "client" thread here
self.addserver(name, host, port)
self.setupserver(name)
return None
def handle_message(self, message):
"""
Handle an API message. Determine whether this needs to be handled
by the local server or forwarded on to another one.
Returns True when message does not need to be handled locally,
and performs forwarding if required.
Returning False indicates this message should be handled locally.
:param core.api.coreapi.CoreMessage message: message to handle
:return: true or false for handling locally
:rtype: bool
"""
servers = set()
handle_locally = False
# Do not forward messages when in definition state
# (for e.g. configuring services)
if self.session.state == EventTypes.DEFINITION_STATE.value:
return False
# Decide whether message should be handled locally or forwarded, or both
if message.message_type == MessageTypes.NODE.value:
handle_locally, servers = self.handlenodemsg(message)
elif message.message_type == MessageTypes.EVENT.value:
# broadcast events everywhere
servers = self.getservers()
elif message.message_type == MessageTypes.CONFIG.value:
# broadcast location and services configuration everywhere
confobj = message.get_tlv(ConfigTlvs.OBJECT.value)
if confobj == "location" or confobj == "services" or \
confobj == "session" or confobj == "all":
servers = self.getservers()
elif message.message_type == MessageTypes.FILE.value:
# broadcast hook scripts and custom service files everywhere
filetype = message.get_tlv(FileTlvs.TYPE.value)
if filetype is not None and (filetype[:5] == "hook:" or filetype[:8] == "service:"):
servers = self.getservers()
if message.message_type == MessageTypes.LINK.value:
# prepare a server list from two node numbers in link message
handle_locally, servers, message = self.handlelinkmsg(message)
logger.info("broker handle link message: %s - %s", handle_locally,
map(lambda x: "%s:%s" % (x.host, x.port), servers))
elif len(servers) == 0:
# check for servers based on node numbers in all messages but link
nn = message.node_numbers()
if len(nn) == 0:
return False
servers = self.getserversbynode(nn[0])
# allow other handlers to process this message (this is used
# by e.g. EMANE to use the link add message to keep counts of
# interfaces on other servers)
for handler in self.handlers:
handler(message)
# perform any message forwarding
handle_locally |= self.forwardmsg(message, servers)
return not handle_locally
def setupserver(self, servername):
"""
Send the appropriate API messages for configuring the specified emulation server.
:param str servername: name of server to configure
:return: nothing
"""
server = self.getserverbyname(servername)
if server is None:
logger.warn("ignoring unknown server: %s" % servername)
return
if server.sock is None or server.host is None or server.port is None:
logger.info("ignoring disconnected server: %s" % servername)
return
# communicate this session"s current state to the server
tlvdata = coreapi.CoreEventTlv.pack(EventTlvs.TYPE.value, self.session.state)
msg = coreapi.CoreEventMessage.pack(0, tlvdata)
server.sock.send(msg)
# send a Configuration message for the broker object and inform the
# server of its local name
tlvdata = ""
tlvdata += coreapi.CoreConfigTlv.pack(ConfigTlvs.OBJECT.value, "broker")
tlvdata += coreapi.CoreConfigTlv.pack(ConfigTlvs.TYPE.value, ConfigFlags.UPDATE.value)
tlvdata += coreapi.CoreConfigTlv.pack(ConfigTlvs.DATA_TYPES.value, (ConfigDataTypes.STRING.value,))
tlvdata += coreapi.CoreConfigTlv.pack(ConfigTlvs.VALUES.value,
"%s:%s:%s" % (server.name, server.host, server.port))
tlvdata += coreapi.CoreConfigTlv.pack(ConfigTlvs.SESSION.value, "%s" % self.session.session_id)
msg = coreapi.CoreConfMessage.pack(0, tlvdata)
server.sock.send(msg)
@staticmethod
def fixupremotetty(msghdr, msgdata, host):
"""
When an interactive TTY request comes from the GUI, snoop the reply
and add an SSH command to the appropriate remote server.
:param msghdr: message header
:param msgdata: message data
:param str host: host address
:return: packed core execute tlv data
"""
msgtype, msgflags, msglen = coreapi.CoreMessage.unpack_header(msghdr)
msgcls = coreapi.CLASS_MAP[msgtype]
msg = msgcls(msgflags, msghdr, msgdata)
nodenum = msg.get_tlv(ExecuteTlvs.NODE.value)
execnum = msg.get_tlv(ExecuteTlvs.NUMBER.value)
cmd = msg.get_tlv(ExecuteTlvs.COMMAND.value)
res = msg.get_tlv(ExecuteTlvs.RESULT.value)
tlvdata = ""
tlvdata += coreapi.CoreExecuteTlv.pack(ExecuteTlvs.NODE.value, nodenum)
tlvdata += coreapi.CoreExecuteTlv.pack(ExecuteTlvs.NUMBER.value, execnum)
tlvdata += coreapi.CoreExecuteTlv.pack(ExecuteTlvs.COMMAND.value, cmd)
title = "\\\"CORE: n%s @ %s\\\"" % (nodenum, host)
res = "ssh -X -f " + host + " xterm -e " + res
tlvdata += coreapi.CoreExecuteTlv.pack(ExecuteTlvs.RESULT.value, res)
return coreapi.CoreExecMessage.pack(msgflags, tlvdata)
def handlenodemsg(self, message):
"""
Determine and return the servers to which this node message should
be forwarded. Also keep track of link-layer nodes and the mapping of
nodes to servers.
:param core.api.coreapi.CoreMessage message: message to handle
:return: boolean for handling locally and set of servers
:rtype: tuple
"""
servers = set()
handle_locally = False
serverfiletxt = None
# snoop Node Message for emulation server TLV and record mapping
n = message.tlv_data[NodeTlvs.NUMBER.value]
# replicate link-layer nodes on all servers
nodetype = message.get_tlv(NodeTlvs.TYPE.value)
if nodetype is not None:
try:
nodecls = nodeutils.get_node_class(NodeTypes(nodetype))
except KeyError:
logger.warn("broker invalid node type %s" % nodetype)
return handle_locally, servers
if nodecls is None:
logger.warn("broker unimplemented node type %s" % nodetype)
return handle_locally, servers
if issubclass(nodecls, PyCoreNet) and nodetype != NodeTypes.WIRELESS_LAN.value:
# network node replicated on all servers; could be optimized
# don"t replicate WLANs, because ebtables rules won"t work
servers = self.getservers()
handle_locally = True
self.addnet(n)
for server in servers:
self.addnodemap(server, n)
# do not record server name for networks since network
# nodes are replicated across all server
return handle_locally, servers
elif issubclass(nodecls, PyCoreNode):
name = message.get_tlv(NodeTlvs.NAME.value)
if name:
serverfiletxt = "%s %s %s" % (n, name, nodecls)
if issubclass(nodecls, PhysicalNode):
# remember physical nodes
self.addphys(n)
# emulation server TLV specifies server
servername = message.get_tlv(NodeTlvs.EMULATION_SERVER.value)
server = self.getserverbyname(servername)
if server is not None:
self.addnodemap(server, n)
if server not in servers:
servers.add(server)
if serverfiletxt and self.session.master:
self.writenodeserver(serverfiletxt, server)
# hook to update coordinates of physical nodes
if n in self.physical_nodes:
self.session.mobility.physnodeupdateposition(message)
return handle_locally, servers
def handlelinkmsg(self, message):
"""
Determine and return the servers to which this link message should
be forwarded. Also build tunnels between different servers or add
opaque data to the link message before forwarding.
:param core.api.coreapi.CoreMessage message: message to handle
:return: boolean to handle locally, a set of server, and message
:rtype: tuple
"""
servers = set()
handle_locally = False
# determine link message destination using non-network nodes
nn = message.node_numbers()
logger.info("checking link nodes (%s) with network nodes (%s)", nn, self.network_nodes)
if nn[0] in self.network_nodes:
if nn[1] in self.network_nodes:
# two network nodes linked together - prevent loops caused by
# the automatic tunnelling
handle_locally = True
else:
servers = self.getserversbynode(nn[1])
elif nn[1] in self.network_nodes:
servers = self.getserversbynode(nn[0])
else:
logger.info("link nodes are not network nodes")
servers1 = self.getserversbynode(nn[0])
logger.info("servers for node(%s): %s", nn[0], servers1)
servers2 = self.getserversbynode(nn[1])
logger.info("servers for node(%s): %s", nn[1], servers2)
# nodes are on two different servers, build tunnels as needed
if servers1 != servers2:
localn = None
if len(servers1) == 0 or len(servers2) == 0:
handle_locally = True
servers = servers1.union(servers2)
host = None
# get the IP of remote server and decide which node number
# is for a local node
for server in servers:
host = server.host
if host is None:
# server is local
handle_locally = True
if server in servers1:
localn = nn[0]
else:
localn = nn[1]
if handle_locally and localn is None:
# having no local node at this point indicates local node is
# the one with the empty server set
if len(servers1) == 0:
localn = nn[0]
elif len(servers2) == 0:
localn = nn[1]
if host is None:
host = self.getlinkendpoint(message, localn == nn[0])
logger.info("handle locally(%s) and local node(%s)", handle_locally, localn)
if localn is None:
message = self.addlinkendpoints(message, servers1, servers2)
elif message.flags & MessageFlags.ADD.value:
self.addtunnel(host, nn[0], nn[1], localn)
elif message.flags & MessageFlags.DELETE.value:
self.deltunnel(nn[0], nn[1])
handle_locally = False
else:
servers = servers1.union(servers2)
return handle_locally, servers, message
def addlinkendpoints(self, message, servers1, servers2):
"""
For a link message that is not handled locally, inform the remote
servers of the IP addresses used as tunnel endpoints by adding
opaque data to the link message.
:param core.api.coreapi.CoreMessage message: message to link end points
:param servers1:
:param servers2:
:return: core link message
:rtype: coreapi.CoreLinkMessage
"""
ip1 = ""
for server in servers1:
if server.host is not None:
ip1 = server.host
break
ip2 = ""
for server in servers2:
if server.host is not None:
ip2 = server.host
break
tlvdata = message.raw_message[coreapi.CoreMessage.header_len:]
tlvdata += coreapi.CoreLinkTlv.pack(LinkTlvs.OPAQUE.value, "%s:%s" % (ip1, ip2))
newraw = coreapi.CoreLinkMessage.pack(message.flags, tlvdata)
msghdr = newraw[:coreapi.CoreMessage.header_len]
return coreapi.CoreLinkMessage(message.flags, msghdr, tlvdata)
def getlinkendpoint(self, msg, first_is_local):
"""
A link message between two different servers has been received,
and we need to determine the tunnel endpoint. First look for
opaque data in the link message, otherwise use the IP of the message
sender (the master server).
:param coreapi.CoreLinkMessage msg:
:param bool first_is_local: is first local
:return: host address
:rtype: str
"""
host = None
opaque = msg.get_tlv(LinkTlvs.OPAQUE.value)
if opaque is not None:
if first_is_local:
host = opaque.split(":")[1]
else:
host = opaque.split(":")[0]
if host == "":
host = None
if host is None:
for session_client in self.session_clients:
# get IP address from API message sender (master)
if session_client.client_address != "":
host = session_client.client_address[0]
break
return host
def handlerawmsg(self, msg):
"""
Helper to invoke message handler, using raw (packed) message bytes.
:param msg: raw message butes
:return: should handle locally or not
:rtype: bool
"""
hdr = msg[:coreapi.CoreMessage.header_len]
msgtype, flags, msglen = coreapi.CoreMessage.unpack_header(hdr)
msgcls = coreapi.CLASS_MAP[msgtype]
return self.handle_message(msgcls(flags, hdr, msg[coreapi.CoreMessage.header_len:]))
def forwardmsg(self, message, servers):
"""
Forward API message to all given servers.
Return True if an empty host/port is encountered, indicating
the message should be handled locally.
:param core.api.coreapi.CoreMessage message: message to forward
:param list servers: server to forward message to
:return: handle locally value
:rtype: bool
"""
handle_locally = len(servers) == 0
for server in servers:
if server.host is None and server.port is None:
# local emulation server, handle this locally
handle_locally = True
elif server.sock is None:
logger.info("server %s @ %s:%s is disconnected" % (
server.name, server.host, server.port))
else:
logger.info("forwarding message to server: %s - %s:\n%s",
server.host, server.port, message)
server.sock.send(message.raw_message)
return handle_locally
def writeservers(self):
"""
Write the server list to a text file in the session directory upon
startup: /tmp/pycore.nnnnn/servers
:return: nothing
"""
servers = self.getservers()
filename = os.path.join(self.session.session_dir, "servers")
master = self.session_id_master
if master is None:
master = self.session.session_id
try:
with open(filename, "w") as f:
f.write("master=%s\n" % master)
for server in servers:
if server.name == "localhost":
continue
lhost, lport = None, None
if server.sock:
lhost, lport = server.sock.getsockname()
f.write("%s %s %s %s %s\n" % (server.name, server.host, server.port, lhost, lport))
except IOError:
logger.exception("error writing server list to the file: %s" % filename)
def writenodeserver(self, nodestr, server):
"""
Creates a /tmp/pycore.nnnnn/nX.conf/server file having the node
and server info. This may be used by scripts for accessing nodes on
other machines, much like local nodes may be accessed via the
VnodeClient class.
:param str nodestr: node string
:param CoreDistributedServer server: core server
:return: nothing
"""
serverstr = "%s %s %s" % (server.name, server.host, server.port)
name = nodestr.split()[1]
dirname = os.path.join(self.session.session_dir, name + ".conf")
filename = os.path.join(dirname, "server")
try:
os.makedirs(dirname)
except OSError:
# directory may already exist from previous distributed run
logger.exception("error creating directory: %s", dirname)
try:
with open(filename, "w") as f:
f.write("%s\n%s\n" % (serverstr, nodestr))
except IOError:
logger.exception("error writing server file %s for node %s" % (filename, name))
def local_instantiation_complete(self):
"""
Set the local server"s instantiation-complete status to True.
:return: nothing
"""
# TODO: do we really want to allow a localhost to not exist?
with self.servers_lock:
server = self.servers.get("localhost")
if server is not None:
server.instantiation_complete = True
# broadcast out instantiate complete
tlvdata = ""
tlvdata += coreapi.CoreEventTlv.pack(EventTlvs.TYPE.value, EventTypes.INSTANTIATION_COMPLETE.value)
message = coreapi.CoreEventMessage.pack(0, tlvdata)
for session_client in self.session_clients:
session_client.sendall(message)
def instantiation_complete(self):
"""
Return True if all servers have completed instantiation, False
otherwise.
:return: have all server completed instantiation
:rtype: bool
"""
with self.servers_lock:
for server in self.servers.itervalues():
if not server.instantiation_complete:
return False
return True
def handle_distributed(self, message):
"""
Handle the session options config message as it has reached the
broker. Options requiring modification for distributed operation should
be handled here.
:param message: message to handle
:return: nothing
"""
if not self.session.master:
return
if message.message_type != MessageTypes.CONFIG.value or message.get_tlv(ConfigTlvs.OBJECT.value) != "session":
return
values_str = message.get_tlv(ConfigTlvs.VALUES.value)
if values_str is None:
return
value_strings = values_str.split('|')
for value_string in value_strings:
key, value = value_string.split('=', 1)
if key == "controlnet":
self.handle_distributed_control_net(message, value_strings, value_strings.index(value_string))
def handle_distributed_control_net(self, message, values, index):
"""
Modify Config Message if multiple control network prefixes are
defined. Map server names to prefixes and repack the message before
it is forwarded to slave servers.
:param message: message to handle
:param list values: values to handle
:param int index: index ti get key value from
:return: nothing
"""
key_value = values[index]
key, value = key_value.split('=', 1)
control_nets = value.split()
if len(control_nets) < 2:
logger.warn("multiple controlnet prefixes do not exist")
return
servers = self.session.broker.getservernames()
if len(servers) < 2:
logger.warn("not distributed")
return
servers.remove("localhost")
# master always gets first prefix
servers.insert(0, "localhost")
# create list of "server1:ctrlnet1 server2:ctrlnet2 ..."
control_nets = map(lambda x: "%s:%s" % (x[0], x[1]), zip(servers, control_nets))
values[index] = "controlnet=%s" % (" ".join(control_nets))
values_str = "|".join(values)
message.tlvdata[ConfigTlvs.VALUES.value] = values_str
message.repack()