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Fix IPv6 case for CIDR format reverse zones (#4652)

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* fix ipv6 case for cidr.Class

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* add check and test case for invalid ipv6 cidr

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* net package is bad at detecting ipv6/ipv4

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* rename Class -> Split

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>
This commit is contained in:
Chris O'Haver 2021-06-04 04:17:17 -04:00 • committed by GitHub
parent a50c0f151f
commit 846ace3f51
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4 changed files with 67 additions and 9 deletions
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6
plugin/normalize.go
View file

@ -163,8 +163,12 @@ func SplitHostPort(s string) (hosts []string, port string, err error) {
return []string{s}, port, nil
}
if s[0] == ':' || (s[0] == '0' && strings.Contains(s, ":")) {
return nil, "", fmt.Errorf("invalid CIDR %s", s)
}
// now check if multiple hosts must be returned.
nets := cidr.Class(n)
nets := cidr.Split(n)
hosts = cidr.Reverse(nets)
return hosts, port, nil
}

46
plugin/normalize_test.go
View file

@ -81,6 +81,50 @@ func TestHostNormalizeExact(t *testing.T) {
{"example.org.:53", []string{"example.org."}},
{"10.0.0.0/8:53", []string{"10.in-addr.arpa."}},
{"10.0.0.0/15", []string{"0.10.in-addr.arpa.", "1.10.in-addr.arpa."}},
{"10.9.3.0/18", []string{"0.9.10.in-addr.arpa.", "1.9.10.in-addr.arpa.", "2.9.10.in-addr.arpa."}},
{"2001:db8::/29", []string{
"8.b.d.0.1.0.0.2.ip6.arpa.",
"9.b.d.0.1.0.0.2.ip6.arpa.",
"a.b.d.0.1.0.0.2.ip6.arpa.",
"b.b.d.0.1.0.0.2.ip6.arpa.",
"c.b.d.0.1.0.0.2.ip6.arpa.",
"d.b.d.0.1.0.0.2.ip6.arpa.",
"e.b.d.0.1.0.0.2.ip6.arpa.",
"f.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"2001:db8::/30", []string{
"8.b.d.0.1.0.0.2.ip6.arpa.",
"9.b.d.0.1.0.0.2.ip6.arpa.",
"a.b.d.0.1.0.0.2.ip6.arpa.",
"b.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"2001:db8::/115", []string{
"0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"2001:db8::/114", []string{
"0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"2.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"3.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"2001:db8::/113", []string{
"0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"2.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"3.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"4.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"6.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
"7.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"2001:db8::/112", []string{
"0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"2001:db8::/108", []string{
"0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
}},
{"::fFFF:B:F/115", nil},
{"dns://example.org", []string{"example.org."}},
}
@ -90,7 +134,7 @@ func TestHostNormalizeExact(t *testing.T) {
sort.Strings(expected)
for j := range expected {
if expected[j] != actual[j] {
t.Errorf("Test %d, expected %v, got %v", i, expected, actual)
t.Errorf("Test %d, expected %v, got %v", i, expected[j], actual[j])
}
}
}

17
plugin/pkg/cidr/cidr.go
View file

@ -4,19 +4,28 @@ package cidr
import (
"math"
"net"
"strings"
"github.com/apparentlymart/go-cidr/cidr"
"github.com/miekg/dns"
)
// Class return slice of "classful" (/8, /16, /24 or /32 only) CIDR's from the CIDR in net.
func Class(n *net.IPNet) []string {
// Split returns a slice of non-overlapping subnets that in union equal the subnet n,
// and where each subnet falls on a reverse name segment boundary.
// for ipv4 this is any multiple of 8 bits (/8, /16, /24 or /32)
// for ipv6 this is any multiple of 4 bits
func Split(n *net.IPNet) []string {
boundary := 8
nstr := n.String()
if strings.Contains(nstr,":") {
boundary = 4
}
ones, _ := n.Mask.Size()
if ones%8 == 0 {
if ones%boundary == 0 {
return []string{n.String()}
}
mask := int(math.Ceil(float64(ones)/8)) * 8
mask := int(math.Ceil(float64(ones)/float64(boundary))) * boundary
networks := nets(n, mask)
cidrs := make([]string, len(networks))
for i := range networks {

7
plugin/pkg/cidr/cidr_test.go
View file

@ -14,12 +14,13 @@ var tests = []struct {
{"10.0.0.0/16", []string{"10.0.0.0/16"}, []string{"0.10.in-addr.arpa."}},
{"192.168.1.1/23", []string{"192.168.0.0/24", "192.168.1.0/24"}, []string{"0.168.192.in-addr.arpa.", "1.168.192.in-addr.arpa."}},
{"10.129.60.0/22", []string{"10.129.60.0/24", "10.129.61.0/24", "10.129.62.0/24", "10.129.63.0/24"}, []string{"60.129.10.in-addr.arpa.", "61.129.10.in-addr.arpa.", "62.129.10.in-addr.arpa.", "63.129.10.in-addr.arpa."}},
{"2001:db8::/31", []string{"2001:db8::/32", "2001:db9::/32"}, []string{"8.b.d.0.1.0.0.2.ip6.arpa.", "9.b.d.0.1.0.0.2.ip6.arpa."}},
}
func TestClass(t *testing.T) {
func TestSplit(t *testing.T) {
for i, tc := range tests {
_, n, _ := net.ParseCIDR(tc.in)
nets := Class(n)
nets := Split(n)
if len(nets) != len(tc.expected) {
t.Errorf("Test %d, expected %d subnets, got %d", i, len(tc.expected), len(nets))
continue
@ -35,7 +36,7 @@ func TestClass(t *testing.T) {
func TestReverse(t *testing.T) {
for i, tc := range tests {
_, n, _ := net.ParseCIDR(tc.in)
nets := Class(n)
nets := Split(n)
reverse := Reverse(nets)
for j := range reverse {
if reverse[j] != tc.zones[j] {