wip: migrate to mono-repo. SPN has already been moved to spn/

service/network/netutils/address.go

@@ -0,0 +1,60 @@
+package netutils
+
+import (
+	"errors"
+	"net"
+	"strconv"
+
+	"github.com/safing/portmaster/service/network/packet"
+)
+
+var errInvalidIP = errors.New("invalid IP address")
+
+// IPPortFromAddr extracts or parses the IP address and port contained in the given address.
+func IPPortFromAddr(addr net.Addr) (ip net.IP, port uint16, err error) {
+	// Convert addr to IP if needed.
+	switch v := addr.(type) {
+	case *net.TCPAddr:
+		return v.IP, uint16(v.Port), nil
+	case *net.UDPAddr:
+		return v.IP, uint16(v.Port), nil
+	case *net.IPAddr:
+		return v.IP, 0, nil
+	case *net.UnixAddr:
+		return nil, 0, errors.New("unix addresses don't have IPs")
+	default:
+		return ParseIPPort(addr.String())
+	}
+}
+
+// ProtocolFromNetwork returns the protocol from the given net, as used in the "net" golang stdlib.
+func ProtocolFromNetwork(net string) (protocol packet.IPProtocol) {
+	switch net {
+	case "tcp", "tcp4", "tcp6":
+		return packet.TCP
+	case "udp", "udp4", "udp6":
+		return packet.UDP
+	default:
+		return 0
+	}
+}
+
+// ParseIPPort parses a <ip>:port formatted address.
+func ParseIPPort(address string) (net.IP, uint16, error) {
+	ipString, portString, err := net.SplitHostPort(address)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	ip := net.ParseIP(ipString)
+	if ip == nil {
+		return nil, 0, errInvalidIP
+	}
+
+	port, err := strconv.ParseUint(portString, 10, 16)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	return ip, uint16(port), nil
+}