Gogogogogogogo

go/pkg/zerotier/inetaddress.go

@@ -0,0 +1,123 @@
+/*
+ * Copyright (c)2019 ZeroTier, Inc.
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file in the project's root directory.
+ *
+ * Change Date: 2023-01-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2.0 of the Apache License.
+ */
+/****/
+
+package zerotier
+
+import (
+	"bytes"
+	"encoding/json"
+	"net"
+	"strconv"
+	"strings"
+	"unsafe"
+)
+
+// InetAddress implements net.Addr but has a ZeroTier-like string representation
+type InetAddress struct {
+	IP   net.IP
+	Port int
+}
+
+// Less returns true if this IP/port is lexicographically less than another
+func (i *InetAddress) Less(i2 *InetAddress) bool {
+	c := bytes.Compare(i.IP, i2.IP)
+	if c < 0 {
+		return true
+	}
+	if c == 0 {
+		return i.Port < i2.Port
+	}
+	return false
+}
+
+// NewInetAddressFromString parses an IP[/port] format address
+func NewInetAddressFromString(s string) *InetAddress {
+	i := new(InetAddress)
+	ss := strings.Split(s, "/")
+	if len(ss) > 0 {
+		i.IP = net.ParseIP(ss[0])
+		i4 := i.IP.To4()
+		if len(i4) == 4 { // down-convert IPv4-in-6 IPs to native IPv4 as this is what all our code expects
+			i.IP = i4
+		}
+		if len(ss) > 1 {
+			p64, _ := strconv.ParseUint(s, 10, 64)
+			i.Port = int(p64 & 0xffff)
+		}
+	}
+	return i
+}
+
+// NewInetAddressFromSockaddr parses a sockaddr_in or sockaddr_in6 C structure (may crash if given something other than these!)
+// This is a convenience wrapper around the CGO functions in node.go.
+func NewInetAddressFromSockaddr(sa unsafe.Pointer) *InetAddress {
+	i := new(InetAddress)
+	if uintptr(sa) != 0 {
+		ua := sockaddrStorageToUDPAddr2(sa)
+		if ua != nil {
+			i.IP = ua.IP
+			i.Port = ua.Port
+		}
+	}
+	return i
+}
+
+// Network returns "udp" to implement net.Addr
+func (i *InetAddress) Network() string {
+	return "udp"
+}
+
+// String returns this address in ZeroTier-canonical IP/port format
+func (i *InetAddress) String() string {
+	return i.IP.String() + "/" + strconv.FormatInt(int64(i.Port), 10)
+}
+
+// Family returns the address family (AFInet etc.) or 0 if none
+func (i *InetAddress) Family() int {
+	switch len(i.IP) {
+	case 4:
+		return AFInet
+	case 16:
+		return AFInet6
+	}
+	return 0
+}
+
+// Valid returns true if both the IP and port have valid values
+func (i *InetAddress) Valid() bool {
+	return (len(i.IP) == 4 || len(i.IP) == 16) && (i.Port > 0 && i.Port < 65536)
+}
+
+// MarshalJSON marshals this MAC as a string
+func (i *InetAddress) MarshalJSON() ([]byte, error) {
+	s := i.String()
+	return json.Marshal(&s)
+}
+
+// UnmarshalJSON unmarshals this MAC from a string
+func (i *InetAddress) UnmarshalJSON(j []byte) error {
+	var s string
+	err := json.Unmarshal(j, &s)
+	if err != nil {
+		return err
+	}
+	*i = *NewInetAddressFromString(s)
+	return nil
+}
+
+// key returns a short array suitable for use as a map[] key for this IP
+func (i *InetAddress) key() (k [3]uint64) {
+	copy(((*[16]byte)(unsafe.Pointer(&k[0])))[:], i.IP)
+	k[2] = uint64(i.Port)
+	return
+}