Update dependencies

vendor/github.com/google/nftables/util.go

@@ -0,0 +1,89 @@
+// Copyright 2018 Google LLC. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nftables
+
+import (
+	"encoding/binary"
+	"net"
+
+	"github.com/google/nftables/binaryutil"
+	"golang.org/x/sys/unix"
+)
+
+func extraHeader(family uint8, resID uint16) []byte {
+	return append([]byte{
+		family,
+		unix.NFNETLINK_V0,
+	}, binaryutil.BigEndian.PutUint16(resID)...)
+}
+
+// General form of address family dependent message, see
+// https://git.netfilter.org/libnftnl/tree/include/linux/netfilter/nfnetlink.h#29
+type NFGenMsg struct {
+	NFGenFamily uint8
+	Version     uint8
+	ResourceID  uint16
+}
+
+func (genmsg *NFGenMsg) Decode(b []byte) {
+	if len(b) < 16 {
+		return
+	}
+	genmsg.NFGenFamily = b[0]
+	genmsg.Version = b[1]
+	genmsg.ResourceID = binary.BigEndian.Uint16(b[2:])
+}
+
+// NetFirstAndLastIP takes the beginning address of an entire network in CIDR
+// notation (e.g. 192.168.1.0/24) and returns the first and last IP addresses
+// within the network (e.g. first 192.168.1.0, last 192.168.1.255).
+//
+// Note that these are the first and last IP addresses, not the first and last
+// *usable* IP addresses (which would be 192.168.1.1 and 192.168.1.254,
+// respectively, for 192.168.1.0/24).
+func NetFirstAndLastIP(networkCIDR string) (first, last net.IP, err error) {
+	_, subnet, err := net.ParseCIDR(networkCIDR)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	first = make(net.IP, len(subnet.IP))
+	last = make(net.IP, len(subnet.IP))
+
+	switch len(subnet.IP) {
+	case net.IPv4len:
+		mask := binary.BigEndian.Uint32(subnet.Mask)
+		ip := binary.BigEndian.Uint32(subnet.IP)
+		// To achieve the first IP address, we need to AND the IP with the mask.
+		// The AND operation will set all bits in the host part to 0.
+		binary.BigEndian.PutUint32(first, ip&mask)
+		// To achieve the last IP address, we need to OR the IP network with the inverted mask.
+		// The AND between the IP and the mask will set all bits in the host part to 0, keeping the network part.
+		// The XOR between the mask and 0xffffffff will set all bits in the host part to 1, and the network part to 0.
+		// The OR operation will keep the host part unchanged, and sets the host part to all 1.
+		binary.BigEndian.PutUint32(last, (ip&mask)|(mask^0xffffffff))
+	case net.IPv6len:
+		mask1 := binary.BigEndian.Uint64(subnet.Mask[:8])
+		mask2 := binary.BigEndian.Uint64(subnet.Mask[8:])
+		ip1 := binary.BigEndian.Uint64(subnet.IP[:8])
+		ip2 := binary.BigEndian.Uint64(subnet.IP[8:])
+		binary.BigEndian.PutUint64(first[:8], ip1&mask1)
+		binary.BigEndian.PutUint64(first[8:], ip2&mask2)
+		binary.BigEndian.PutUint64(last[:8], (ip1&mask1)|(mask1^0xffffffffffffffff))
+		binary.BigEndian.PutUint64(last[8:], (ip2&mask2)|(mask2^0xffffffffffffffff))
+	}
+
+	return first, last, nil
+}