Merge pull request #271 from danwinship/ipfamily

Add IPFamilyOf() / IPFamilyOfString() / IPFamilyOfCIDR() / IPFamilyOfCIDRString()

Author: k8s-ci-robot

net/ipfamily.go

@@ -0,0 +1,181 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+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 net
+
+import (
+	"fmt"
+	"net"
+)
+
+// IPFamily refers to a specific family if not empty, i.e. "4" or "6".
+type IPFamily string
+
+// Constants for valid IPFamilys:
+const (
+	IPFamilyUnknown IPFamily = ""
+
+	IPv4 IPFamily = "4"
+	IPv6 IPFamily = "6"
+)
+
+// IsDualStackIPs returns true if:
+// - all elements of ips are valid
+// - at least one IP from each family (v4 and v6) is present
+func IsDualStackIPs(ips []net.IP) (bool, error) {
+	v4Found := false
+	v6Found := false
+	for i, ip := range ips {
+		switch IPFamilyOf(ip) {
+		case IPv4:
+			v4Found = true
+		case IPv6:
+			v6Found = true
+		default:
+			return false, fmt.Errorf("invalid IP[%d]: %v", i, ip)
+		}
+	}
+
+	return (v4Found && v6Found), nil
+}
+
+// IsDualStackIPStrings returns true if:
+// - all elements of ips can be parsed as IPs
+// - at least one IP from each family (v4 and v6) is present
+func IsDualStackIPStrings(ips []string) (bool, error) {
+	parsedIPs := make([]net.IP, 0, len(ips))
+	for i, ip := range ips {
+		parsedIP := ParseIPSloppy(ip)
+		if parsedIP == nil {
+			return false, fmt.Errorf("invalid IP[%d]: %v", i, ip)
+		}
+		parsedIPs = append(parsedIPs, parsedIP)
+	}
+	return IsDualStackIPs(parsedIPs)
+}
+
+// IsDualStackCIDRs returns true if:
+// - all elements of cidrs are non-nil
+// - at least one CIDR from each family (v4 and v6) is present
+func IsDualStackCIDRs(cidrs []*net.IPNet) (bool, error) {
+	v4Found := false
+	v6Found := false
+	for i, cidr := range cidrs {
+		switch IPFamilyOfCIDR(cidr) {
+		case IPv4:
+			v4Found = true
+		case IPv6:
+			v6Found = true
+		default:
+			return false, fmt.Errorf("invalid CIDR[%d]: %v", i, cidr)
+		}
+	}
+
+	return (v4Found && v6Found), nil
+}
+
+// IsDualStackCIDRStrings returns if
+// - all elements of cidrs can be parsed as CIDRs
+// - at least one CIDR from each family (v4 and v6) is present
+func IsDualStackCIDRStrings(cidrs []string) (bool, error) {
+	parsedCIDRs, err := ParseCIDRs(cidrs)
+	if err != nil {
+		return false, err
+	}
+	return IsDualStackCIDRs(parsedCIDRs)
+}
+
+// IPFamilyOf returns the IP family of ip, or IPFamilyUnknown if it is invalid.
+func IPFamilyOf(ip net.IP) IPFamily {
+	switch {
+	case ip.To4() != nil:
+		return IPv4
+	case ip.To16() != nil:
+		return IPv6
+	default:
+		return IPFamilyUnknown
+	}
+}
+
+// IPFamilyOfString returns the IP family of ip, or IPFamilyUnknown if ip cannot
+// be parsed as an IP.
+func IPFamilyOfString(ip string) IPFamily {
+	return IPFamilyOf(ParseIPSloppy(ip))
+}
+
+// IPFamilyOfCIDR returns the IP family of cidr.
+func IPFamilyOfCIDR(cidr *net.IPNet) IPFamily {
+	if cidr == nil {
+		return IPFamilyUnknown
+	}
+	return IPFamilyOf(cidr.IP)
+}
+
+// IPFamilyOfCIDRString returns the IP family of cidr.
+func IPFamilyOfCIDRString(cidr string) IPFamily {
+	ip, _, _ := ParseCIDRSloppy(cidr)
+	return IPFamilyOf(ip)
+}
+
+// IsIPv6 returns true if netIP is IPv6 (and false if it is IPv4, nil, or invalid).
+func IsIPv6(netIP net.IP) bool {
+	return IPFamilyOf(netIP) == IPv6
+}
+
+// IsIPv6String returns true if ip contains a single IPv6 address and nothing else. It
+// returns false if ip is an empty string, an IPv4 address, or anything else that is not a
+// single IPv6 address.
+func IsIPv6String(ip string) bool {
+	return IPFamilyOfString(ip) == IPv6
+}
+
+// IsIPv6CIDR returns true if a cidr is a valid IPv6 CIDR. It returns false if cidr is
+// nil or an IPv4 CIDR. Its behavior is not defined if cidr is invalid.
+func IsIPv6CIDR(cidr *net.IPNet) bool {
+	return IPFamilyOfCIDR(cidr) == IPv6
+}
+
+// IsIPv6CIDRString returns true if cidr contains a single IPv6 CIDR and nothing else. It
+// returns false if cidr is an empty string, an IPv4 CIDR, or anything else that is not a
+// single valid IPv6 CIDR.
+func IsIPv6CIDRString(cidr string) bool {
+	return IPFamilyOfCIDRString(cidr) == IPv6
+}
+
+// IsIPv4 returns true if netIP is IPv4 (and false if it is IPv6, nil, or invalid).
+func IsIPv4(netIP net.IP) bool {
+	return IPFamilyOf(netIP) == IPv4
+}
+
+// IsIPv4String returns true if ip contains a single IPv4 address and nothing else. It
+// returns false if ip is an empty string, an IPv6 address, or anything else that is not a
+// single IPv4 address.
+func IsIPv4String(ip string) bool {
+	return IPFamilyOfString(ip) == IPv4
+}
+
+// IsIPv4CIDR returns true if cidr is a valid IPv4 CIDR. It returns false if cidr is nil
+// or an IPv6 CIDR. Its behavior is not defined if cidr is invalid.
+func IsIPv4CIDR(cidr *net.IPNet) bool {
+	return IPFamilyOfCIDR(cidr) == IPv4
+}
+
+// IsIPv4CIDRString returns true if cidr contains a single IPv4 CIDR and nothing else. It
+// returns false if cidr is an empty string, an IPv6 CIDR, or anything else that is not a
+// single valid IPv4 CIDR.
+func IsIPv4CIDRString(cidr string) bool {
+	return IPFamilyOfCIDRString(cidr) == IPv4
+}