initial import (Boeing r1752, NRL r878)

daemon/core/netns/vif.py

@@ -0,0 +1,168 @@
+#
+# CORE
+# Copyright (c)2011-2012 the Boeing Company.
+# See the LICENSE file included in this distribution.
+#
+# authors: Tom Goff <thomas.goff@boeing.com>
+#          Jeff Ahrenholz <jeffrey.m.ahrenholz@boeing.com>
+#
+'''
+vif.py: PyCoreNetIf classes that implement the interfaces available
+under Linux.
+'''
+
+import os, signal, shutil, sys, subprocess, vnodeclient, threading, string
+import random, time
+from core.api import coreapi
+from core.misc.utils import *
+from core.constants import *
+from core.coreobj import PyCoreObj, PyCoreNode, PyCoreNetIf, Position
+from core.emane.nodes import EmaneNode
+
+checkexec([IP_BIN])
+
+class VEth(PyCoreNetIf):
+    def __init__(self, node, name, localname, mtu = 1500, net = None,
+                 start = True):
+        # note that net arg is ignored
+        PyCoreNetIf.__init__(self, node = node, name = name, mtu = mtu)
+        self.localname = localname
+        self.up = False
+        if start:
+            self.startup()
+
+    def startup(self):
+        check_call([IP_BIN, "link", "add", "name", self.localname,
+                    "type", "veth", "peer", "name", self.name])
+        check_call([IP_BIN, "link", "set", self.localname, "up"])
+        self.up = True
+
+    def shutdown(self):
+        if not self.up:
+            return
+        if self.node:
+            self.node.cmd([IP_BIN, "-6", "addr", "flush", "dev", self.name])
+        if self.localname:
+            mutedetach([IP_BIN, "link", "delete", self.localname])
+        self.up = False
+
+
+class TunTap(PyCoreNetIf):
+    ''' TUN/TAP virtual device in TAP mode
+    '''
+    def __init__(self, node, name, localname, mtu = 1500, net = None,
+                 start = True):
+        PyCoreNetIf.__init__(self, node = node, name = name, mtu = mtu)
+        self.localname = localname
+        self.up = False
+        self.transport_type = "virtual"
+        if start:
+            self.startup()
+
+    def startup(self):
+        # TODO: more sophisticated TAP creation here
+        #   Debian does not support -p (tap) option, RedHat does.
+        # For now, this is disabled to allow the TAP to be created by another 
+        # system (e.g. EMANE's emanetransportd)
+        #check_call(["tunctl", "-t", self.name])
+        # self.install()
+        self.up = True
+
+    def shutdown(self):
+        if not self.up:
+            return
+        self.node.cmd([IP_BIN, "-6", "addr", "flush", "dev", self.name])
+        #if self.name:
+        #    mutedetach(["tunctl", "-d", self.localname])
+        self.up = False
+
+    def install(self):
+        ''' Install this TAP into its namespace. This is not done from the
+            startup() method but called at a later time when a userspace
+            program (running on the host) has had a chance to open the socket
+            end of the TAP.
+        '''
+        netns = str(self.node.pid)
+        # check for presence of device - tap device may not appear right away
+        # waits ~= stime * ( 2 ** attempts) seconds 
+        attempts = 9
+        stime = 0.01
+        while attempts > 0:
+            try:
+                mutecheck_call([IP_BIN, "link", "show", self.localname])
+                break
+            except Exception, e:
+                msg = "ip link show %s error (%d): %s" % \
+                        (self.localname, attempts, e)
+                if attempts > 1:
+                    msg += ", retrying..."
+                self.node.info(msg)
+            time.sleep(stime)
+            stime *= 2
+            attempts -= 1
+        # install tap device into namespace
+        try:
+            check_call([IP_BIN, "link", "set", self.localname, "netns", netns])
+        except Exception, e:
+            msg = "error installing TAP interface %s, command:" % self.localname
+            msg += "ip link set %s netns %s" % (self.localname, netns)
+            self.node.exception(coreapi.CORE_EXCP_LEVEL_ERROR, self.localname, msg)
+            self.node.warn(msg)
+            return
+        self.node.cmd([IP_BIN, "link", "set", self.localname,
+                       "name", self.name])
+        for addr in self.addrlist:
+            self.node.cmd([IP_BIN, "addr", "add", str(addr),
+                  "dev", self.name])
+        self.node.cmd([IP_BIN, "link", "set", self.name,  "up"])
+
+class GreTap(PyCoreNetIf):
+    ''' GRE TAP device for tunneling between emulation servers.
+        Uses the "gretap" tunnel device type from Linux which is a GRE device
+        having a MAC address. The MAC address is required for bridging.
+    '''
+    def __init__(self, node = None, name = None, session = None, mtu = 1458,
+                 remoteip = None, objid = None, localip = None, ttl = 255,
+                 key = None, start = True):
+        PyCoreNetIf.__init__(self, node = node, name = name, mtu = mtu)
+        self.session = session
+        if objid is None:
+            # from PyCoreObj
+            objid = (((id(self) >> 16) ^ (id(self) & 0xffff)) & 0xffff)
+        self.objid = objid
+        sessionid = self.session.shortsessionid()
+        # interface name on the local host machine
+        self.localname = "gt.%s.%s" % (self.objid, sessionid)
+        self.transport_type = "raw"
+        if not start:
+            self.up = False
+            return
+        
+        if remoteip is None:
+            raise ValueError, "missing remote IP required for GRE TAP device"
+        cmd = ("ip", "link", "add", self.localname, "type", "gretap",
+               "remote", str(remoteip))
+        if localip:
+            cmd += ("local", str(localip))
+        if ttl:
+            cmd += ("ttl", str(ttl))
+        if key:
+            cmd += ("key", str(key))
+        check_call(cmd)
+        cmd = ("ip", "link", "set", self.localname, "up")
+        check_call(cmd)
+        self.up = True
+
+    def shutdown(self):
+        if self.localname:
+            cmd = ("ip", "link", "set", self.localname, "down")
+            check_call(cmd)
+            cmd = ("ip", "link", "del", self.localname)
+            check_call(cmd)
+            self.localname = None
+    
+    def tonodemsg(self, flags):
+        return None
+        
+    def tolinkmsgs(self, flags):
+        return []