move matcher to separate file

Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
This commit is contained in:
Kristoffer Dalby 2023-04-28 11:05:12 +02:00 committed by Juan Font
parent 56b63c6e10
commit 644be822d5
3 changed files with 261 additions and 133 deletions

133
acls.go
View File

@ -15,7 +15,6 @@ import (
"github.com/rs/zerolog/log"
"github.com/samber/lo"
"github.com/tailscale/hujson"
"go4.org/netipx"
"gopkg.in/yaml.v3"
"tailscale.com/envknob"
"tailscale.com/tailcfg"
@ -808,135 +807,3 @@ func (pol *ACLPolicy) getIPsFromIPPrefix(
return lo.Uniq(val), nil
}
// This is borrowed from, and updated to use IPSet
// https://github.com/tailscale/tailscale/blob/71029cea2ddf82007b80f465b256d027eab0f02d/wgengine/filter/tailcfg.go#L97-L162
// TODO(kradalby): contribute upstream and make public
var (
zeroIP4 = netip.AddrFrom4([4]byte{})
zeroIP6 = netip.AddrFrom16([16]byte{})
)
// parseIPSet parses arg as one:
//
// - an IP address (IPv4 or IPv6)
// - the string "*" to match everything (both IPv4 & IPv6)
// - a CIDR (e.g. "192.168.0.0/16")
// - a range of two IPs, inclusive, separated by hyphen ("2eff::1-2eff::0800")
//
// bits, if non-nil, is the legacy SrcBits CIDR length to make a IP
// address (without a slash) treated as a CIDR of *bits length.
// nolint
func parseIPSet(arg string, bits *int) (*netipx.IPSet, error) {
var ipSet netipx.IPSetBuilder
if arg == "*" {
ipSet.AddPrefix(netip.PrefixFrom(zeroIP4, 0))
ipSet.AddPrefix(netip.PrefixFrom(zeroIP6, 0))
return ipSet.IPSet()
}
if strings.Contains(arg, "/") {
pfx, err := netip.ParsePrefix(arg)
if err != nil {
return nil, err
}
if pfx != pfx.Masked() {
return nil, fmt.Errorf("%v contains non-network bits set", pfx)
}
ipSet.AddPrefix(pfx)
return ipSet.IPSet()
}
if strings.Count(arg, "-") == 1 {
ip1s, ip2s, _ := strings.Cut(arg, "-")
ip1, err := netip.ParseAddr(ip1s)
if err != nil {
return nil, err
}
ip2, err := netip.ParseAddr(ip2s)
if err != nil {
return nil, err
}
r := netipx.IPRangeFrom(ip1, ip2)
if !r.IsValid() {
return nil, fmt.Errorf("invalid IP range %q", arg)
}
for _, prefix := range r.Prefixes() {
ipSet.AddPrefix(prefix)
}
return ipSet.IPSet()
}
ip, err := netip.ParseAddr(arg)
if err != nil {
return nil, fmt.Errorf("invalid IP address %q", arg)
}
bits8 := uint8(ip.BitLen())
if bits != nil {
if *bits < 0 || *bits > int(bits8) {
return nil, fmt.Errorf("invalid CIDR size %d for IP %q", *bits, arg)
}
bits8 = uint8(*bits)
}
ipSet.AddPrefix(netip.PrefixFrom(ip, int(bits8)))
return ipSet.IPSet()
}
type Match struct {
Srcs *netipx.IPSet
Dests *netipx.IPSet
}
func MatchFromFilterRule(rule tailcfg.FilterRule) Match {
srcs := new(netipx.IPSetBuilder)
dests := new(netipx.IPSetBuilder)
for _, srcIP := range rule.SrcIPs {
set, _ := parseIPSet(srcIP, nil)
srcs.AddSet(set)
}
for _, dest := range rule.DstPorts {
set, _ := parseIPSet(dest.IP, nil)
dests.AddSet(set)
}
srcsSet, _ := srcs.IPSet()
destsSet, _ := dests.IPSet()
match := Match{
Srcs: srcsSet,
Dests: destsSet,
}
return match
}
func (m *Match) SrcsContainsIPs(ips []netip.Addr) bool {
for _, ip := range ips {
if m.Srcs.Contains(ip) {
return true
}
}
return false
}
func (m *Match) DestsContainsIP(ips []netip.Addr) bool {
for _, ip := range ips {
if m.Dests.Contains(ip) {
return true
}
}
return false
}

142
matcher.go Normal file
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@ -0,0 +1,142 @@
package headscale
import (
"fmt"
"net/netip"
"strings"
"go4.org/netipx"
"tailscale.com/tailcfg"
)
// This is borrowed from, and updated to use IPSet
// https://github.com/tailscale/tailscale/blob/71029cea2ddf82007b80f465b256d027eab0f02d/wgengine/filter/tailcfg.go#L97-L162
// TODO(kradalby): contribute upstream and make public.
var (
zeroIP4 = netip.AddrFrom4([4]byte{})
zeroIP6 = netip.AddrFrom16([16]byte{})
)
// parseIPSet parses arg as one:
//
// - an IP address (IPv4 or IPv6)
// - the string "*" to match everything (both IPv4 & IPv6)
// - a CIDR (e.g. "192.168.0.0/16")
// - a range of two IPs, inclusive, separated by hyphen ("2eff::1-2eff::0800")
//
// bits, if non-nil, is the legacy SrcBits CIDR length to make a IP
// address (without a slash) treated as a CIDR of *bits length.
// nolint
func parseIPSet(arg string, bits *int) (*netipx.IPSet, error) {
var ipSet netipx.IPSetBuilder
if arg == "*" {
ipSet.AddPrefix(netip.PrefixFrom(zeroIP4, 0))
ipSet.AddPrefix(netip.PrefixFrom(zeroIP6, 0))
return ipSet.IPSet()
}
if strings.Contains(arg, "/") {
pfx, err := netip.ParsePrefix(arg)
if err != nil {
return nil, err
}
if pfx != pfx.Masked() {
return nil, fmt.Errorf("%v contains non-network bits set", pfx)
}
ipSet.AddPrefix(pfx)
return ipSet.IPSet()
}
if strings.Count(arg, "-") == 1 {
ip1s, ip2s, _ := strings.Cut(arg, "-")
ip1, err := netip.ParseAddr(ip1s)
if err != nil {
return nil, err
}
ip2, err := netip.ParseAddr(ip2s)
if err != nil {
return nil, err
}
r := netipx.IPRangeFrom(ip1, ip2)
if !r.IsValid() {
return nil, fmt.Errorf("invalid IP range %q", arg)
}
for _, prefix := range r.Prefixes() {
ipSet.AddPrefix(prefix)
}
return ipSet.IPSet()
}
ip, err := netip.ParseAddr(arg)
if err != nil {
return nil, fmt.Errorf("invalid IP address %q", arg)
}
bits8 := uint8(ip.BitLen())
if bits != nil {
if *bits < 0 || *bits > int(bits8) {
return nil, fmt.Errorf("invalid CIDR size %d for IP %q", *bits, arg)
}
bits8 = uint8(*bits)
}
ipSet.AddPrefix(netip.PrefixFrom(ip, int(bits8)))
return ipSet.IPSet()
}
type Match struct {
Srcs *netipx.IPSet
Dests *netipx.IPSet
}
func MatchFromFilterRule(rule tailcfg.FilterRule) Match {
srcs := new(netipx.IPSetBuilder)
dests := new(netipx.IPSetBuilder)
for _, srcIP := range rule.SrcIPs {
set, _ := parseIPSet(srcIP, nil)
srcs.AddSet(set)
}
for _, dest := range rule.DstPorts {
set, _ := parseIPSet(dest.IP, nil)
dests.AddSet(set)
}
srcsSet, _ := srcs.IPSet()
destsSet, _ := dests.IPSet()
match := Match{
Srcs: srcsSet,
Dests: destsSet,
}
return match
}
func (m *Match) SrcsContainsIPs(ips []netip.Addr) bool {
for _, ip := range ips {
if m.Srcs.Contains(ip) {
return true
}
}
return false
}
func (m *Match) DestsContainsIP(ips []netip.Addr) bool {
for _, ip := range ips {
if m.Dests.Contains(ip) {
return true
}
}
return false
}

119
matcher_test.go Normal file
View File

@ -0,0 +1,119 @@
package headscale
import (
"net/netip"
"reflect"
"testing"
"go4.org/netipx"
)
func Test_parseIPSet(t *testing.T) {
set := func(ips []string, prefixes []string) *netipx.IPSet {
var builder netipx.IPSetBuilder
for _, ip := range ips {
builder.Add(netip.MustParseAddr(ip))
}
for _, pre := range prefixes {
builder.AddPrefix(netip.MustParsePrefix(pre))
}
s, _ := builder.IPSet()
return s
}
type args struct {
arg string
bits *int
}
tests := []struct {
name string
args args
want *netipx.IPSet
wantErr bool
}{
{
name: "simple ip4",
args: args{
arg: "10.0.0.1",
bits: nil,
},
want: set([]string{
"10.0.0.1",
}, []string{}),
wantErr: false,
},
{
name: "simple ip6",
args: args{
arg: "2001:db8:abcd:1234::2",
bits: nil,
},
want: set([]string{
"2001:db8:abcd:1234::2",
}, []string{}),
wantErr: false,
},
{
name: "wildcard",
args: args{
arg: "*",
bits: nil,
},
want: set([]string{}, []string{
"0.0.0.0/0",
"::/0",
}),
wantErr: false,
},
{
name: "prefix4",
args: args{
arg: "192.168.0.0/16",
bits: nil,
},
want: set([]string{}, []string{
"192.168.0.0/16",
}),
wantErr: false,
},
{
name: "prefix6",
args: args{
arg: "2001:db8:abcd:1234::/64",
bits: nil,
},
want: set([]string{}, []string{
"2001:db8:abcd:1234::/64",
}),
wantErr: false,
},
{
name: "range4",
args: args{
arg: "192.168.0.0-192.168.255.255",
bits: nil,
},
want: set([]string{}, []string{
"192.168.0.0/16",
}),
wantErr: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
got, err := parseIPSet(tt.args.arg, tt.args.bits)
if (err != nil) != tt.wantErr {
t.Errorf("parseIPSet() error = %v, wantErr %v", err, tt.wantErr)
return
}
if !reflect.DeepEqual(got, tt.want) {
t.Errorf("parseIPSet() = %v, want %v", got, tt.want)
}
})
}
}