policy: reject unsupported fields (#2764)

hscontrol/policy/v2/utils.go

@@ -2,7 +2,6 @@ package v2
 
 import (
 	"errors"
-	"fmt"
 	"slices"
 	"strconv"
 	"strings"
@@ -97,72 +96,3 @@ func parsePort(portStr string) (uint16, error) {
 
 	return uint16(port), nil
 }
-
-// For some reason golang.org/x/net/internal/iana is an internal package.
-const (
-	protocolICMP     = 1   // Internet Control Message
-	protocolIGMP     = 2   // Internet Group Management
-	protocolIPv4     = 4   // IPv4 encapsulation
-	protocolTCP      = 6   // Transmission Control
-	protocolEGP      = 8   // Exterior Gateway Protocol
-	protocolIGP      = 9   // any private interior gateway (used by Cisco for their IGRP)
-	protocolUDP      = 17  // User Datagram
-	protocolGRE      = 47  // Generic Routing Encapsulation
-	protocolESP      = 50  // Encap Security Payload
-	protocolAH       = 51  // Authentication Header
-	protocolIPv6ICMP = 58  // ICMP for IPv6
-	protocolSCTP     = 132 // Stream Control Transmission Protocol
-	ProtocolFC       = 133 // Fibre Channel
-)
-
-// parseProtocol reads the proto field of the ACL and generates a list of
-// protocols that will be allowed, following the IANA IP protocol number
-// https://www.iana.org/assignments/protocol-numbers/protocol-numbers.xhtml
-//
-// If the ACL proto field is empty, it allows ICMPv4, ICMPv6, TCP, and UDP,
-// as per Tailscale behaviour (see tailcfg.FilterRule).
-//
-// Also returns a boolean indicating if the protocol
-// requires all the destinations to use wildcard as port number (only TCP,
-// UDP and SCTP support specifying ports).
-func parseProtocol(protocol string) ([]int, bool, error) {
-	switch protocol {
-	case "":
-		return nil, false, nil
-	case "igmp":
-		return []int{protocolIGMP}, true, nil
-	case "ipv4", "ip-in-ip":
-		return []int{protocolIPv4}, true, nil
-	case "tcp":
-		return []int{protocolTCP}, false, nil
-	case "egp":
-		return []int{protocolEGP}, true, nil
-	case "igp":
-		return []int{protocolIGP}, true, nil
-	case "udp":
-		return []int{protocolUDP}, false, nil
-	case "gre":
-		return []int{protocolGRE}, true, nil
-	case "esp":
-		return []int{protocolESP}, true, nil
-	case "ah":
-		return []int{protocolAH}, true, nil
-	case "sctp":
-		return []int{protocolSCTP}, false, nil
-	case "icmp":
-		return []int{protocolICMP, protocolIPv6ICMP}, true, nil
-
-	default:
-		protocolNumber, err := strconv.Atoi(protocol)
-		if err != nil {
-			return nil, false, fmt.Errorf("parsing protocol number: %w", err)
-		}
-
-		// TODO(kradalby): What is this?
-		needsWildcard := protocolNumber != protocolTCP &&
-			protocolNumber != protocolUDP &&
-			protocolNumber != protocolSCTP
-
-		return []int{protocolNumber}, needsWildcard, nil
-	}
-}