def validate_router_id(cluster_id):
    if not isinstance(cluster_id, str):
        raise ConfigTypeError(conf_name=CLUSTER_ID)
    if not is_valid_ipv4(cluster_id):
        raise ConfigValueError(desc='Invalid cluster id %s' % cluster_id)

    return cluster_id

def validate_rpc_host(ip):
    """
    Validates the given ip for use as RPC server address.
    """
    if not is_valid_ipv4(ip) and not is_valid_ipv6(ip):
        raise ApplicationException(
            desc='Invalid RPC ip address: %s' % ip)
    return ip

def is_valid_ip_addr(addr):
    # Note: Allows empty IP Address (means length=0).
    # e.g.) L2VPN MAC advertisement of Cisco NX-OS
    if not (addr is None
            or validation.is_valid_ipv4(addr)
            or validation.is_valid_ipv6(addr)):
        raise ConfigValueError(conf_name=IP_ADDR,
                               conf_value=addr)

def ipv4_mapped_ipv6(ipv4):
    if not is_valid_ipv4(ipv4):
        raise ValueError('Invalid ipv4 address given %s.' % ipv4)
    ipv4n = socket.inet_pton(socket.AF_INET, ipv4)
    ipv6_hex = '00' * 10 + 'ff' * 2 + bytes2hex(ipv4n)
    ipv6n = hex2byte(ipv6_hex)
    ipv6 = socket.inet_ntop(socket.AF_INET6, ipv6n)
    return ipv6

def validate_router_id(router_id):
    if not router_id:
        raise MissingRequiredConf(conf_name=ROUTER_ID)

    if not isinstance(router_id, str):
        raise ConfigTypeError(conf_name=ROUTER_ID)
    if not is_valid_ipv4(router_id):
        raise ConfigValueError(desc='Invalid router id %s' % router_id)

    return router_id

    def from_bytes(cls, recv_bytes, total_msg_len):
        # Validate OPEN message length.
        if len(recv_bytes) < 10:
            raise BadLen(Open.TYPE_CODE, len(recv_bytes) + cls.HEADER_SIZE)

        version, asnum, holdtime, bgpid, paramlen = \
            struct.unpack_from('!BHH4sB', recv_bytes)

        if len(recv_bytes) != (10 + paramlen):
            # TODO(PH): Check what RFC says to do here.
            LOG.debug('Open message: too short.')

        offset = 10

        # BGP implementation MUST reject Hold Time values of one or two
        # seconds.
        if holdtime <= 2:
            raise UnacceptableHoldTime()

        # BGP Identifier field MUST represents a valid unicast IP host address.
        bgpid = socket.inet_ntoa(bgpid)
        if not is_valid_ipv4(bgpid):
            raise BadBgpId()

        # Parse optional parameters.
        caps = OrderedDict()
        unrec_params = OrderedDict()
        while offset < len(recv_bytes):
            ptype, plen = struct.unpack_from('BB', recv_bytes, offset)
            offset += 2
            value = recv_bytes[offset:offset + plen]
            offset += plen

            # Parse capabilities optional parameter.
            if ptype == CAP_OPT_PARA_TYPE:
                bgp_caps = capabilities.decode(value)
                # store decoded bgp capabilities by their capability-code
                for cap in bgp_caps:
                    cap_code = cap.CODE
                    if cap_code in caps:
                        caps[cap_code].append(cap)
                    else:
                        caps[cap_code] = [cap]
            else:
                # Other unrecognized optional parameters.
                unrec_params[ptype] = value

        # Un-recognized capabilities are passed on, its up to application to
        # check if unrec-optional-paramters are a problem and send NOTIFICATION
        return cls(version, asnum, holdtime, bgpid, caps, unrec_params)

    def add_to_vrf(self, route_dist, prefix, next_hop, route_family):
        """Adds `prefix` to VRF identified by `route_dist` with given
         `next_hop`.

        Returns assigned VPN label.
        """
        from ryu.services.protocols.bgp.core import BgpCoreError

        assert route_dist and prefix and next_hop
        if route_family not in (VRF_RF_IPV4, VRF_RF_IPV6):
            raise ValueError('Given route_family %s is not supported.' %
                             route_family)

        vrf_table = None
        table_id = (route_dist, route_family)
        if route_family == VRF_RF_IPV4:
            vrf_table = self._tables.get(table_id)
            if vrf_table is None:
                raise BgpCoreError(desc='VRF table for RD: %s does not '
                                        'exist.' % route_dist)
            if not is_valid_ipv4_prefix(prefix) or not is_valid_ipv4(next_hop):
                raise BgpCoreError(desc='Invalid Ipv4 prefix or nexthop.')
            ip, masklen = prefix.split('/')
            prefix = IPAddrPrefix(int(masklen), ip)
        elif route_family == VRF_RF_IPV6:
            vrf_table = self._tables.get(table_id)
            if vrf_table is None:
                raise BgpCoreError(desc='VRF table for RD: %s does not '
                                        'exist.' % route_dist)
            if not is_valid_ipv6_prefix(prefix) or not is_valid_ipv6(next_hop):
                raise BgpCoreError(desc='Invalid Ipv6 prefix or nexthop.')
            ip6, masklen = prefix.split('/')
            prefix = IP6AddrPrefix(int(masklen), ip6)

        return vrf_table.insert_vrf_path(
            prefix, next_hop=next_hop,
            gen_lbl=True
        )

    def __init__(self, version, asnum, holdtime, bgpid, caps,
                 unrec_params=None):
        # Validate arguments.
        if version < 1:
            raise ValueError('Invalid version number %s' % version)
        if not is_valid_old_asn(asnum):
            raise ValueError('Invalid AS number %s' % asnum)
        if holdtime <= 2:
            raise ValueError('Holdtime has to be greater than 2 sec.')
        if not caps:
            raise ValueError('Invalid capabilities.')
        if not is_valid_ipv4(bgpid):
            raise ValueError('Invalid bgp ID, should be valid IPv4, '
                             'but given %s' % bgpid)

        BgpMessage.__init__(self)
        self._version = version
        self._holdtime = holdtime
        self._asnum = asnum
        self._bgpid = bgpid
        self._caps = caps
        self._unrec_params = unrec_params
        if not unrec_params:
            self._unrec_params = OrderedDict()

    def __init__(self, route_family, next_hop, nlri_list, reserved=None):
        if not (hasattr(route_family, 'afi') and
                hasattr(route_family, 'safi')):
            raise ValueError('Invalid parameter value for route_family %s.' %
                             route_family)

        if not next_hop:
            raise ValueError('Invalid next_hop %s' % next_hop)

        # MpReachNlri attribute should have next-hop belonging to same
        # route-family
        if ((route_family == RF_IPv4_VPN and not is_valid_ipv4(next_hop)) or
                (route_family == RF_IPv6_VPN and not is_valid_ipv6(next_hop))):
            raise ValueError('Next hop should belong to %s route family' %
                             route_family)

        if not nlri_list:
            nlri_list = []

        RcgPathAttr.__init__(self)
        self._route_family = route_family
        self._next_hop = next_hop
        self._nlri_list = nlri_list
        self._reserved = reserved

def validate_local_address(ip_address):
    if not is_valid_ipv4(ip_address):
        raise ConfigValueError(desc='Invalid local ip_address: %s' %
                               ip_address)
    return ip_address

def _validate_rpc_ip(rpc_server_ip):
    """Validates given ip for use as rpc host bind address.
    """
    if not is_valid_ipv4(rpc_server_ip):
        raise NetworkControllerError(desc='Invalid rpc ip address.')
    return rpc_server_ip

    def update_vrf_table(self, route_dist, prefix=None, next_hop=None,
                         route_family=None, route_type=None, tunnel_type=None,
                         is_withdraw=False, redundancy_mode=None,
                         pmsi_tunnel_type=None, **kwargs):
        """Update a BGP route in the VRF table identified by `route_dist`
        with the given `next_hop`.

        If `is_withdraw` is False, which is the default, add a BGP route
        to the VRF table identified by `route_dist` with the given
        `next_hop`.
        If `is_withdraw` is True, remove a BGP route from the VRF table
        and the given `next_hop` is ignored.

        If `route_family` is VRF_RF_L2_EVPN, `route_type` and `kwargs`
        are required to construct EVPN NLRI and `prefix` is ignored.

        ``redundancy_mode`` specifies a redundancy mode type.

`       `pmsi_tunnel_type` specifies the type of the PMSI tunnel attribute
         used to encode the multicast tunnel identifier.
        This field is advertised only if route_type is
        EVPN_MULTICAST_ETAG_ROUTE.

        Returns assigned VPN label.
        """
        from ryu.services.protocols.bgp.core import BgpCoreError

        assert route_dist

        if is_withdraw:
            gen_lbl = False
            next_hop = None
        else:
            gen_lbl = True
            if not (is_valid_ipv4(next_hop) or is_valid_ipv6(next_hop)):
                raise BgpCoreError(
                    desc='Invalid IPv4/IPv6 nexthop: %s' % next_hop)

        vrf_table = self._tables.get((route_dist, route_family))
        if vrf_table is None:
            raise BgpCoreError(
                desc='VRF table  does not exist: route_dist=%s, '
                     'route_family=%s' % (route_dist, route_family))

        vni = kwargs.get('vni', None)

        if route_family == VRF_RF_IPV4:
            if not is_valid_ipv4_prefix(prefix):
                raise BgpCoreError(desc='Invalid IPv4 prefix: %s' % prefix)
            ip, masklen = prefix.split('/')
            prefix = IPAddrPrefix(int(masklen), ip)
        elif route_family == VRF_RF_IPV6:
            if not is_valid_ipv6_prefix(prefix):
                raise BgpCoreError(desc='Invalid IPv6 prefix: %s' % prefix)
            ip6, masklen = prefix.split('/')
            prefix = IP6AddrPrefix(int(masklen), ip6)
        elif route_family == VRF_RF_L2_EVPN:
            assert route_type
            if route_type == EvpnMacIPAdvertisementNLRI.ROUTE_TYPE_NAME:
                # MPLS labels will be assigned automatically
                kwargs['mpls_labels'] = []
            subclass = EvpnNLRI._lookup_type_name(route_type)
            kwargs['route_dist'] = route_dist
            esi = kwargs.get('esi', None)
            if esi is not None:
                if isinstance(esi, dict):
                    esi_type = esi.get('type', 0)
                    esi_class = EvpnEsi._lookup_type(esi_type)
                    kwargs['esi'] = esi_class.from_jsondict(esi)
                else:  # isinstance(esi, numbers.Integral)
                    kwargs['esi'] = EvpnArbitraryEsi(
                        type_desc.Int9.from_user(esi))
            if vni is not None:
                # Disable to generate MPLS labels,
                # because encapsulation type is not MPLS.
                from ryu.services.protocols.bgp.api.prefix import (
                    TUNNEL_TYPE_VXLAN, TUNNEL_TYPE_NVGRE)
                assert tunnel_type in [
                    None, TUNNEL_TYPE_VXLAN, TUNNEL_TYPE_NVGRE]
                gen_lbl = False
            prefix = subclass(**kwargs)
        else:
            raise BgpCoreError(
                desc='Unsupported route family %s' % route_family)

        # We do not check if we have a path to given prefix, we issue
        # withdrawal. Hence multiple withdrawals have not side effect.
        return vrf_table.insert_vrf_path(
            nlri=prefix, next_hop=next_hop, gen_lbl=gen_lbl,
            is_withdraw=is_withdraw, redundancy_mode=redundancy_mode,
            vni=vni, tunnel_type=tunnel_type,
            pmsi_tunnel_type=pmsi_tunnel_type)

def is_valid_next_hop(next_hop_addr):
    return validation.is_valid_ipv4(next_hop_addr)

 def test_is_valid_ipv4(self):
     ok_(validation.is_valid_ipv4("10.0.0.1"))

 def validate_rpc_ip(cls, ip):
     """Validates given ip for use as rpc host bind address.
     """
     if not is_valid_ipv4(ip):
         raise ApplicationException(desc='Invalid rpc ip address.')
     return ip

def is_valid_next_hop(next_hop):
    if not (validation.is_valid_ipv4(next_hop)
            or validation.is_valid_ipv6(next_hop)):
        raise ConfigValueError(conf_name=NEXT_HOP,
                               conf_value=next_hop)

 def test_is_valid_ipv4_not_dot(self):
     eq_(False, validation.is_valid_ipv4("192:168:0:1"))

def is_valid_gw_ip_addr(addr):
    if not (validation.is_valid_ipv4(addr)
            or validation.is_valid_ipv6(addr)):
        raise ConfigValueError(conf_name=GW_IP_ADDR,
                               conf_value=addr)

    def update_vrf_table(self, route_dist, prefix=None, next_hop=None,
                         route_family=None, route_type=None, tunnel_type=None,
                         is_withdraw=False, **kwargs):
        """Update a BGP route in the VRF table identified by `route_dist`
        with the given `next_hop`.

        If `is_withdraw` is False, which is the default, add a BGP route
        to the VRF table identified by `route_dist` with the given
        `next_hop`.
        If `is_withdraw` is True, remove a BGP route from the VRF table
        and the given `next_hop` is ignored.

        If `route_family` is VRF_RF_L2_EVPN, `route_type` and `kwargs`
        are required to construct EVPN NLRI and `prefix` is ignored.

        Returns assigned VPN label.
        """
        from ryu.services.protocols.bgp.core import BgpCoreError

        assert route_dist

        if is_withdraw:
            gen_lbl = False
            next_hop = None
        else:
            gen_lbl = True
            if not (is_valid_ipv4(next_hop) or is_valid_ipv6(next_hop)):
                raise BgpCoreError(
                    desc='Invalid IPv4/IPv6 nexthop: %s' % next_hop)

        vrf_table = self._tables.get((route_dist, route_family))
        if vrf_table is None:
            raise BgpCoreError(
                desc='VRF table  does not exist: route_dist=%s, '
                     'route_family=%s' % (route_dist, route_family))

        if route_family == VRF_RF_IPV4:
            if not is_valid_ipv4_prefix(prefix):
                raise BgpCoreError(desc='Invalid IPv4 prefix: %s' % prefix)
            ip, masklen = prefix.split('/')
            prefix = IPAddrPrefix(int(masklen), ip)
        elif route_family == VRF_RF_IPV6:
            if not is_valid_ipv6_prefix(prefix):
                raise BgpCoreError(desc='Invalid IPv6 prefix: %s' % prefix)
            ip6, masklen = prefix.split('/')
            prefix = IP6AddrPrefix(int(masklen), ip6)
        elif route_family == VRF_RF_L2_EVPN:
            assert route_type
            if route_type == EvpnMacIPAdvertisementNLRI.ROUTE_TYPE_NAME:
                # MPLS labels will be assigned automatically
                kwargs['mpls_labels'] = []
            subclass = EvpnNLRI._lookup_type_name(route_type)
            kwargs['route_dist'] = route_dist
            esi = kwargs.get('esi', None)
            if esi is not None:
                # Note: Currently, we support arbitrary 9-octet ESI value only.
                kwargs['esi'] = EvpnArbitraryEsi(type_desc.Int9.from_user(esi))
            if 'vni' in kwargs:
                # Disable to generate MPLS labels, because encapsulation type
                # is not MPLS.
                from ryu.services.protocols.bgp.api.prefix import (
                    TUNNEL_TYPE_VXLAN, TUNNEL_TYPE_NVGRE)
                assert tunnel_type in [TUNNEL_TYPE_VXLAN, TUNNEL_TYPE_NVGRE]
                gen_lbl = False
            prefix = subclass(**kwargs)
        else:
            raise BgpCoreError(
                desc='Unsupported route family %s' % route_family)

        # We do not check if we have a path to given prefix, we issue
        # withdrawal. Hence multiple withdrawals have not side effect.
        return vrf_table.insert_vrf_path(
            nlri=prefix, next_hop=next_hop, gen_lbl=gen_lbl,
            is_withdraw=is_withdraw, tunnel_type=tunnel_type)