diff options
| -rwxr-xr-x | utilities/ovs-tcpdump.in | 54 |
1 files changed, 36 insertions, 18 deletions
diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in index 5ec02383c..82d1bedfa 100755 --- a/utilities/ovs-tcpdump.in +++ b/utilities/ovs-tcpdump.in @@ -14,15 +14,14 @@ # See the License for the specific language governing permissions and # limitations under the License. -import fcntl - import os import pwd from random import randint -import struct import subprocess import sys import time +import struct +import fcntl try: from netifaces import interfaces @@ -52,8 +51,8 @@ except Exception: print(" the correct location.") sys.exit(1) -tapdev_fd = None _make_taps = {} +_del_taps = {} _make_mirror_name = {} IFNAMSIZ_LINUX = 15 # this is the max name size, excluding the null byte. @@ -67,21 +66,25 @@ def _doexec(*args, **kwargs): return proc -def _install_tap_linux(tap_name, mtu_value=None): - """Uses /dev/net/tun to create a tap device""" - global tapdev_fd +def _install_dst_if_linux(tap_name, mtu_value=None): + ret_code = _doexec( + *['ip', 'link', 'add', str(tap_name), 'type', 'dummy'] + ).wait() - IFF_TAP = 0x0002 - IFF_NO_PI = 0x1000 - TUNSETIFF = 0x400454CA # This is derived by printf() of TUNSETIFF - TUNSETOWNER = TUNSETIFF + 2 + if ret_code != 0: + """If dummy driver is not present, fall back on /dev/net/tun""" + IFF_TAP = 0x0002 + IFF_NO_PI = 0x1000 + TUNSETIFF = 0x400454CA # This is derived by printf() of TUNSETIFF + TUNSETOWNER = TUNSETIFF + 2 - tapdev_fd = os.open('/dev/net/tun', os.O_RDWR) - ifr = struct.pack('16sH', tap_name.encode('utf8'), IFF_TAP | IFF_NO_PI) - fcntl.ioctl(tapdev_fd, TUNSETIFF, ifr) - fcntl.ioctl(tapdev_fd, TUNSETOWNER, os.getegid()) + tapdev_fd = os.open('/dev/net/tun', os.O_RDWR) + ifr = struct.pack('16sH', tap_name.encode('utf8'), IFF_TAP | IFF_NO_PI) + fcntl.ioctl(tapdev_fd, TUNSETIFF, ifr) + fcntl.ioctl(tapdev_fd, TUNSETOWNER, os.getegid()) + + time.sleep(1) # required to give the new device settling time - time.sleep(1) # required to give the new device settling time if mtu_value is not None: pipe = _doexec( *(['ip', 'link', 'set', 'dev', str(tap_name), 'mtu', @@ -93,14 +96,22 @@ def _install_tap_linux(tap_name, mtu_value=None): pipe.wait() +def _remove_dst_if_linux(tap_name): + _doexec( + *['ip', 'link', 'del', str(tap_name)] + ).wait() + + def _make_linux_mirror_name(interface_name): if len(interface_name) > IFNAMSIZ_LINUX - 2: return "ovsmi%06d" % randint(1, 999999) return "mi%s" % interface_name -_make_taps['linux'] = _install_tap_linux -_make_taps['linux2'] = _install_tap_linux +_make_taps['linux'] = _install_dst_if_linux +_make_taps['linux2'] = _install_dst_if_linux +_del_taps['linux'] = _remove_dst_if_linux +_del_taps['linux2'] = _remove_dst_if_linux _make_mirror_name['linux'] = _make_linux_mirror_name _make_mirror_name['linux2'] = _make_linux_mirror_name @@ -455,6 +466,9 @@ def main(): mirror_interface not in interfaces(): _make_taps[sys.platform](mirror_interface, ovsdb.interface_mtu(interface)) + tap_created = True + else: + tap_created = False if mirror_interface not in interfaces(): print("ERROR: Please create an interface called `%s`" % @@ -480,6 +494,8 @@ def main(): print("ERROR: Unable to properly setup the mirror: %s." % str(oe)) try: ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface)) + if tap_created is True: + _del_taps[sys.platform](mirror_interface) except Exception: pass sys.exit(1) @@ -498,6 +514,8 @@ def main(): ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface)) ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface)) + if tap_created is True: + _del_taps[sys.platform](mirror_interface) except Exception: print("Unable to tear down the ports and mirrors.") print("Please use ovs-vsctl to remove the ports and mirrors created.") |