Pull request 2043: AG-26544-ipset-persistent-entries

Squashed commit of the following:

commit e5daef40330daf97cfd259006586fcc0196fc8e1
Merge: 7c6e63a39 cd09ba63b
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Tue Oct 24 14:06:13 2023 +0300

    Merge branch 'master' into AG-26544-ipset-persistent-entries

commit 7c6e63a393a05ae9e6007af1ae539b3c70b49fda
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Oct 23 16:28:34 2023 +0300

    ipset: imp docs

commit cfb5d8a6573e33ed466a3767290da84e6db96167
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Fri Oct 20 18:09:01 2023 +0300

    ipset: imp code

commit 4ef03c9e0066ddb10f11c653338699f8001ae0de
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Oct 18 20:17:16 2023 +0300

    ipset: imp docs

commit 544982b5d7d333d2575da655ebcf15b941fd74d0
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Oct 16 19:05:43 2023 +0300

    ipset: add persistent entries
This commit is contained in:
Stanislav Chzhen 2023-10-24 14:17:14 +03:00
parent cd09ba63b6
commit e3cc3b0642
2 changed files with 202 additions and 64 deletions

View file

@ -3,6 +3,7 @@
package ipset
import (
"bytes"
"fmt"
"net"
"strings"
@ -38,19 +39,69 @@ func newManager(ipsetConf []string) (set Manager, err error) {
// defaultDial is the default netfilter dialing function.
func defaultDial(pf netfilter.ProtoFamily, conf *netlink.Config) (conn ipsetConn, err error) {
conn, err = ipset.Dial(pf, conf)
c, err := ipset.Dial(pf, conf)
if err != nil {
return nil, err
}
return conn, nil
return &queryConn{c}, nil
}
// queryConn is the [ipsetConn] implementation with listAll method, which
// returns the list of properties of all available ipsets.
type queryConn struct {
*ipset.Conn
}
// type check
var _ ipsetConn = (*queryConn)(nil)
// listAll returns the list of properties of all available ipsets.
//
// TODO(s.chzhen): Use https://github.com/vishvananda/netlink.
func (qc *queryConn) listAll() (sets []props, err error) {
msg, err := netfilter.MarshalNetlink(
netfilter.Header{
// The family doesn't seem to matter. See TODO on parseIpsetConfig.
Family: qc.Conn.Family,
SubsystemID: netfilter.NFSubsysIPSet,
MessageType: netfilter.MessageType(ipset.CmdList),
Flags: netlink.Request | netlink.Dump,
},
[]netfilter.Attribute{{
Type: uint16(ipset.AttrProtocol),
Data: []byte{ipset.Protocol},
}},
)
if err != nil {
return nil, fmt.Errorf("marshaling netlink msg: %w", err)
}
// We assume it's OK to call a method of an unexported type
// [ipset.connector], since there is no negative effects.
ms, err := qc.Conn.Conn.Query(msg)
if err != nil {
return nil, fmt.Errorf("querying netlink msg: %w", err)
}
for i, s := range ms {
p := props{}
err = p.unmarshalMessage(s)
if err != nil {
return nil, fmt.Errorf("unmarshaling netlink msg at index %d: %w", i, err)
}
sets = append(sets, p)
}
return sets, nil
}
// ipsetConn is the ipset conn interface.
type ipsetConn interface {
Add(name string, entries ...*ipset.Entry) (err error)
Close() (err error)
Header(name string) (p *ipset.HeaderPolicy, err error)
listAll() (sets []props, err error)
}
// dialer creates an ipsetConn.
@ -58,8 +109,75 @@ type dialer func(pf netfilter.ProtoFamily, conf *netlink.Config) (conn ipsetConn
// props contains one Linux Netfilter ipset properties.
type props struct {
name string
// name of the ipset.
name string
// family of the IP addresses in the ipset.
family netfilter.ProtoFamily
// isPersistent indicates that ipset has no timeout parameter and all
// entries are added permanently.
isPersistent bool
}
// unmarshalMessage unmarshals netlink message and sets the properties of the
// ipset.
func (p *props) unmarshalMessage(msg netlink.Message) (err error) {
_, attrs, err := netfilter.UnmarshalNetlink(msg)
if err != nil {
// Don't wrap the error since it's informative enough as is.
return err
}
// By default ipset has no timeout parameter.
p.isPersistent = true
for _, a := range attrs {
p.parseAttribute(a)
}
return nil
}
// parseAttribute parses netfilter attribute and sets the name and family of
// the ipset.
func (p *props) parseAttribute(a netfilter.Attribute) {
switch ipset.AttributeType(a.Type) {
case ipset.AttrData:
p.parseAttrData(a)
case ipset.AttrSetName:
// Trim the null character.
p.name = string(bytes.Trim(a.Data, "\x00"))
case ipset.AttrFamily:
p.family = netfilter.ProtoFamily(a.Data[0])
default:
// Go on.
}
}
// parseAttrData parses attribute data and sets the timeout of the ipset.
func (p *props) parseAttrData(a netfilter.Attribute) {
for _, a := range a.Children {
switch ipset.AttributeType(a.Type) {
case ipset.AttrTimeout:
timeout := a.Uint32()
p.isPersistent = timeout == 0
default:
// Go on.
}
}
}
// unit is a convenient alias for struct{}.
type unit = struct{}
// ipsInIpset is the type of a set of IP-address-to-ipset mappings.
type ipsInIpset map[ipInIpsetEntry]unit
// ipInIpsetEntry is the type for entries in an ipsInIpset set.
type ipInIpsetEntry struct {
ipsetName string
ipArr [net.IPv6len]byte
}
// manager is the Linux Netfilter ipset manager.
@ -72,6 +190,13 @@ type manager struct {
// mu protects all properties below.
mu *sync.Mutex
// TODO(a.garipov): Currently, the ipset list is static, and we don't
// read the IPs already in sets, so we can assume that all incoming IPs
// are either added to all corresponding ipsets or not. When that stops
// being the case, for example if we add dynamic reconfiguration of
// ipsets, this map will need to become a per-ipset-name one.
addedIPs ipsInIpset
ipv4Conn ipsetConn
ipv6Conn ipsetConn
}
@ -96,8 +221,8 @@ func (m *manager) dialNetfilter(conf *netlink.Config) (err error) {
return nil
}
// parseIpsetConfig parses one ipset configuration string.
func parseIpsetConfig(confStr string) (hosts, ipsetNames []string, err error) {
// parseIpsetConfigLine parses one ipset configuration line.
func parseIpsetConfigLine(confStr string) (hosts, ipsetNames []string, err error) {
confStr = strings.TrimSpace(confStr)
hostsAndNames := strings.Split(confStr, "/")
if len(hostsAndNames) != 2 {
@ -125,50 +250,53 @@ func parseIpsetConfig(confStr string) (hosts, ipsetNames []string, err error) {
return hosts, ipsetNames, nil
}
// ipsetProps returns the properties of an ipset with the given name.
func (m *manager) ipsetProps(name string) (set props, err error) {
// The family doesn't seem to matter when we use a header query, so
// query only the IPv4 one.
// parseIpsetConfig parses the ipset configuration and stores ipsets. It
// returns an error if the configuration can't be used.
func (m *manager) parseIpsetConfig(ipsetConf []string) (err error) {
// The family doesn't seem to matter when we use a header query, so query
// only the IPv4 one.
//
// TODO(a.garipov): Find out if this is a bug or a feature.
var res *ipset.HeaderPolicy
res, err = m.ipv4Conn.Header(name)
all, err := m.ipv4Conn.listAll()
if err != nil {
return set, err
// Don't wrap the error since it's informative enough as is.
return err
}
if res == nil || res.Family == nil {
return set, errors.Error("empty response or no family data")
for _, p := range all {
m.nameToIpset[p.name] = p
}
family := netfilter.ProtoFamily(res.Family.Value)
if family != netfilter.ProtoIPv4 && family != netfilter.ProtoIPv6 {
return set, fmt.Errorf("unexpected ipset family %d", family)
for i, confStr := range ipsetConf {
var hosts, ipsetNames []string
hosts, ipsetNames, err = parseIpsetConfigLine(confStr)
if err != nil {
return fmt.Errorf("config line at idx %d: %w", i, err)
}
var ipsets []props
ipsets, err = m.ipsets(ipsetNames)
if err != nil {
return fmt.Errorf("getting ipsets from config line at idx %d: %w", i, err)
}
for _, host := range hosts {
m.domainToIpsets[host] = append(m.domainToIpsets[host], ipsets...)
}
}
return props{
name: name,
family: family,
}, nil
return nil
}
// ipsets returns currently known ipsets.
func (m *manager) ipsets(names []string) (sets []props, err error) {
for _, name := range names {
set, ok := m.nameToIpset[name]
if ok {
sets = append(sets, set)
continue
for _, n := range names {
p, ok := m.nameToIpset[n]
if !ok {
return nil, fmt.Errorf("unknown ipset %q", n)
}
set, err = m.ipsetProps(name)
if err != nil {
return nil, fmt.Errorf("querying ipset %q: %w", name, err)
}
m.nameToIpset[name] = set
sets = append(sets, set)
sets = append(sets, p)
}
return sets, nil
@ -186,6 +314,8 @@ func newManagerWithDialer(ipsetConf []string, dial dialer) (mgr Manager, err err
domainToIpsets: make(map[string][]props),
dial: dial,
addedIPs: make(ipsInIpset),
}
err = m.dialNetfilter(&netlink.Config{})
@ -201,26 +331,9 @@ func newManagerWithDialer(ipsetConf []string, dial dialer) (mgr Manager, err err
return nil, fmt.Errorf("dialing netfilter: %w", err)
}
for i, confStr := range ipsetConf {
var hosts, ipsetNames []string
hosts, ipsetNames, err = parseIpsetConfig(confStr)
if err != nil {
return nil, fmt.Errorf("config line at idx %d: %w", i, err)
}
var ipsets []props
ipsets, err = m.ipsets(ipsetNames)
if err != nil {
return nil, fmt.Errorf(
"getting ipsets from config line at idx %d: %w",
i,
err,
)
}
for _, host := range hosts {
m.domainToIpsets[host] = append(m.domainToIpsets[host], ipsets...)
}
err = m.parseIpsetConfig(ipsetConf)
if err != nil {
return nil, fmt.Errorf("getting ipsets: %w", err)
}
return m, nil
@ -259,8 +372,19 @@ func (m *manager) addIPs(host string, set props, ips []net.IP) (n int, err error
}
var entries []*ipset.Entry
var newAddedEntries []ipInIpsetEntry
for _, ip := range ips {
e := ipInIpsetEntry{
ipsetName: set.name,
}
copy(e.ipArr[:], ip.To16())
if _, added := m.addedIPs[e]; added {
continue
}
entries = append(entries, ipset.NewEntry(ipset.EntryIP(ip)))
newAddedEntries = append(newAddedEntries, e)
}
n = len(entries)
@ -283,6 +407,15 @@ func (m *manager) addIPs(host string, set props, ips []net.IP) (n int, err error
return 0, fmt.Errorf("adding %q%s to ipset %q: %w", host, ips, set.name, err)
}
// Only add these to the cache once we're sure that all of them were
// actually sent to the ipset.
for _, e := range newAddedEntries {
s := m.nameToIpset[e.ipsetName]
if s.isPersistent {
m.addedIPs[e] = unit{}
}
}
return n, nil
}

View file

@ -21,8 +21,12 @@ type fakeConn struct {
ipv4Entries *[]*ipset.Entry
ipv6Header *ipset.HeaderPolicy
ipv6Entries *[]*ipset.Entry
sets []props
}
// type check
var _ ipsetConn = (*fakeConn)(nil)
// Add implements the [ipsetConn] interface for *fakeConn.
func (c *fakeConn) Add(name string, entries ...*ipset.Entry) (err error) {
if strings.Contains(name, "ipv4") {
@ -43,15 +47,9 @@ func (c *fakeConn) Close() (err error) {
return nil
}
// Header implements the [ipsetConn] interface for *fakeConn.
func (c *fakeConn) Header(name string) (p *ipset.HeaderPolicy, err error) {
if strings.Contains(name, "ipv4") {
return c.ipv4Header, nil
} else if strings.Contains(name, "ipv6") {
return c.ipv6Header, nil
}
return nil, errors.Error("test: ipset not found")
// listAll implements the [ipsetConn] interface for *fakeConn.
func (c *fakeConn) listAll() (sets []props, err error) {
return c.sets, nil
}
func TestManager_Add(t *testing.T) {
@ -76,6 +74,13 @@ func TestManager_Add(t *testing.T) {
Family: ipset.NewUInt8Box(uint8(netfilter.ProtoIPv6)),
},
ipv6Entries: &ipv6Entries,
sets: []props{{
name: "ipv4set",
family: netfilter.ProtoIPv4,
}, {
name: "ipv6set",
family: netfilter.ProtoIPv6,
}},
}, nil
}