diff options
Diffstat (limited to 'cloudinit/sources/helpers/netlink.py')
| -rw-r--r-- | cloudinit/sources/helpers/netlink.py | 102 |
1 files changed, 91 insertions, 11 deletions
diff --git a/cloudinit/sources/helpers/netlink.py b/cloudinit/sources/helpers/netlink.py index c2ad587b..e13d6834 100644 --- a/cloudinit/sources/helpers/netlink.py +++ b/cloudinit/sources/helpers/netlink.py @@ -185,6 +185,54 @@ def read_rta_oper_state(data): return InterfaceOperstate(ifname, operstate) +def wait_for_nic_attach_event(netlink_socket, existing_nics): + '''Block until a single nic is attached. + + :param: netlink_socket: netlink_socket to receive events + :param: existing_nics: List of existing nics so that we can skip them. + :raises: AssertionError if netlink_socket is none. + ''' + LOG.debug("Preparing to wait for nic attach.") + ifname = None + + def should_continue_cb(iname, carrier, prevCarrier): + if iname in existing_nics: + return True + nonlocal ifname + ifname = iname + return False + + # We can return even if the operational state of the new nic is DOWN + # because we set it to UP before doing dhcp. + read_netlink_messages(netlink_socket, + None, + [RTM_NEWLINK], + [OPER_UP, OPER_DOWN], + should_continue_cb) + return ifname + + +def wait_for_nic_detach_event(netlink_socket): + '''Block until a single nic is detached and its operational state is down. + + :param: netlink_socket: netlink_socket to receive events. + ''' + LOG.debug("Preparing to wait for nic detach.") + ifname = None + + def should_continue_cb(iname, carrier, prevCarrier): + nonlocal ifname + ifname = iname + return False + + read_netlink_messages(netlink_socket, + None, + [RTM_DELLINK], + [OPER_DOWN], + should_continue_cb) + return ifname + + def wait_for_media_disconnect_connect(netlink_socket, ifname): '''Block until media disconnect and connect has happened on an interface. Listens on netlink socket to receive netlink events and when the carrier @@ -198,10 +246,42 @@ def wait_for_media_disconnect_connect(netlink_socket, ifname): assert (netlink_socket is not None), ("netlink socket is none") assert (ifname is not None), ("interface name is none") assert (len(ifname) > 0), ("interface name cannot be empty") + + def should_continue_cb(iname, carrier, prevCarrier): + # check for carrier down, up sequence + isVnetSwitch = (prevCarrier == OPER_DOWN) and (carrier == OPER_UP) + if isVnetSwitch: + LOG.debug("Media switch happened on %s.", ifname) + return False + return True + + LOG.debug("Wait for media disconnect and reconnect to happen") + read_netlink_messages(netlink_socket, + ifname, + [RTM_NEWLINK, RTM_DELLINK], + [OPER_UP, OPER_DOWN], + should_continue_cb) + + +def read_netlink_messages(netlink_socket, + ifname_filter, + rtm_types, + operstates, + should_continue_callback): + ''' Reads from the netlink socket until the condition specified by + the continuation callback is met. + + :param: netlink_socket: netlink_socket to receive events. + :param: ifname_filter: if not None, will only listen for this interface. + :param: rtm_types: Type of netlink events to listen for. + :param: operstates: Operational states to listen. + :param: should_continue_callback: Specifies when to stop listening. + ''' + if netlink_socket is None: + raise RuntimeError("Netlink socket is none") + data = bytes() carrier = OPER_UP prevCarrier = OPER_UP - data = bytes() - LOG.debug("Wait for media disconnect and reconnect to happen") while True: recv_data = read_netlink_socket(netlink_socket, SELECT_TIMEOUT) if recv_data is None: @@ -223,26 +303,26 @@ def wait_for_media_disconnect_connect(netlink_socket, ifname): padlen = (nlheader.length+PAD_ALIGNMENT-1) & ~(PAD_ALIGNMENT-1) offset = offset + padlen LOG.debug('offset to next netlink message: %d', offset) - # Ignore any messages not new link or del link - if nlheader.type not in [RTM_NEWLINK, RTM_DELLINK]: + # Continue if we are not interested in this message. + if nlheader.type not in rtm_types: continue interface_state = read_rta_oper_state(nl_msg) if interface_state is None: LOG.debug('Failed to read rta attributes: %s', interface_state) continue - if interface_state.ifname != ifname: + if (ifname_filter is not None and + interface_state.ifname != ifname_filter): LOG.debug( "Ignored netlink event on interface %s. Waiting for %s.", - interface_state.ifname, ifname) + interface_state.ifname, ifname_filter) continue - if interface_state.operstate not in [OPER_UP, OPER_DOWN]: + if interface_state.operstate not in operstates: continue prevCarrier = carrier carrier = interface_state.operstate - # check for carrier down, up sequence - isVnetSwitch = (prevCarrier == OPER_DOWN) and (carrier == OPER_UP) - if isVnetSwitch: - LOG.debug("Media switch happened on %s.", ifname) + if not should_continue_callback(interface_state.ifname, + carrier, + prevCarrier): return data = data[offset:] |