AdGuardHome/internal/home/client.go

262 lines
6.5 KiB
Go

package home
import (
"encoding"
"fmt"
"net"
"net/netip"
"slices"
"strings"
"time"
"github.com/AdguardTeam/AdGuardHome/internal/dnsforward"
"github.com/AdguardTeam/AdGuardHome/internal/filtering"
"github.com/AdguardTeam/AdGuardHome/internal/filtering/safesearch"
"github.com/AdguardTeam/dnsproxy/proxy"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/log"
"github.com/AdguardTeam/golibs/stringutil"
"github.com/google/uuid"
)
// UID is the type for the unique IDs of persistent clients.
type UID uuid.UUID
// NewUID returns a new persistent client UID. Any error returned is an error
// from the cryptographic randomness reader.
func NewUID() (uid UID, err error) {
uuidv7, err := uuid.NewV7()
return UID(uuidv7), err
}
// type check
var _ encoding.TextMarshaler = UID{}
// MarshalText implements the [encoding.TextMarshaler] for UID.
func (uid UID) MarshalText() ([]byte, error) {
return uuid.UUID(uid).MarshalText()
}
// type check
var _ encoding.TextUnmarshaler = (*UID)(nil)
// UnmarshalText implements the [encoding.TextUnmarshaler] interface for UID.
func (uid *UID) UnmarshalText(data []byte) error {
return (*uuid.UUID)(uid).UnmarshalText(data)
}
// persistentClient contains information about persistent clients.
type persistentClient struct {
// upstreamConfig is the custom upstream configuration for this client. If
// it's nil, it has not been initialized yet. If it's non-nil and empty,
// there are no valid upstreams. If it's non-nil and non-empty, these
// upstream must be used.
upstreamConfig *proxy.CustomUpstreamConfig
// TODO(d.kolyshev): Make safeSearchConf a pointer.
safeSearchConf filtering.SafeSearchConfig
SafeSearch filtering.SafeSearch
// BlockedServices is the configuration of blocked services of a client.
BlockedServices *filtering.BlockedServices
Name string
Tags []string
Upstreams []string
IPs []netip.Addr
// TODO(s.chzhen): Use netutil.Prefix.
Subnets []netip.Prefix
MACs []net.HardwareAddr
ClientIDs []string
// UID is the unique identifier of the persistent client.
UID UID
UpstreamsCacheSize uint32
UpstreamsCacheEnabled bool
UseOwnSettings bool
FilteringEnabled bool
SafeBrowsingEnabled bool
ParentalEnabled bool
UseOwnBlockedServices bool
IgnoreQueryLog bool
IgnoreStatistics bool
}
// setTags sets the tags if they are known, otherwise logs an unknown tag.
func (c *persistentClient) setTags(tags []string, known *stringutil.Set) {
for _, t := range tags {
if !known.Has(t) {
log.Info("skipping unknown tag %q", t)
continue
}
c.Tags = append(c.Tags, t)
}
slices.Sort(c.Tags)
}
// setIDs parses a list of strings into typed fields and returns an error if
// there is one.
func (c *persistentClient) setIDs(ids []string) (err error) {
for _, id := range ids {
err = c.setID(id)
if err != nil {
return err
}
}
slices.SortFunc(c.IPs, netip.Addr.Compare)
// TODO(s.chzhen): Use netip.PrefixCompare in Go 1.23.
slices.SortFunc(c.Subnets, subnetCompare)
slices.SortFunc(c.MACs, slices.Compare[net.HardwareAddr])
slices.Sort(c.ClientIDs)
return nil
}
// subnetCompare is a comparison function for the two subnets. It returns -1 if
// x sorts before y, 1 if x sorts after y, and 0 if their relative sorting
// position is the same.
func subnetCompare(x, y netip.Prefix) (cmp int) {
if x == y {
return 0
}
xAddr, xBits := x.Addr(), x.Bits()
yAddr, yBits := y.Addr(), y.Bits()
if xBits == yBits {
return xAddr.Compare(yAddr)
}
if xBits > yBits {
return -1
} else {
return 1
}
}
// setID parses id into typed field if there is no error.
func (c *persistentClient) setID(id string) (err error) {
if id == "" {
return errors.Error("clientid is empty")
}
var ip netip.Addr
if ip, err = netip.ParseAddr(id); err == nil {
c.IPs = append(c.IPs, ip)
return nil
}
var subnet netip.Prefix
if subnet, err = netip.ParsePrefix(id); err == nil {
c.Subnets = append(c.Subnets, subnet)
return nil
}
var mac net.HardwareAddr
if mac, err = net.ParseMAC(id); err == nil {
c.MACs = append(c.MACs, mac)
return nil
}
err = dnsforward.ValidateClientID(id)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return err
}
c.ClientIDs = append(c.ClientIDs, strings.ToLower(id))
return nil
}
// ids returns a list of client ids containing at least one element.
func (c *persistentClient) ids() (ids []string) {
ids = make([]string, 0, c.idsLen())
for _, ip := range c.IPs {
ids = append(ids, ip.String())
}
for _, subnet := range c.Subnets {
ids = append(ids, subnet.String())
}
for _, mac := range c.MACs {
ids = append(ids, mac.String())
}
return append(ids, c.ClientIDs...)
}
// idsLen returns a length of client ids.
func (c *persistentClient) idsLen() (n int) {
return len(c.IPs) + len(c.Subnets) + len(c.MACs) + len(c.ClientIDs)
}
// equalIDs returns true if the ids of the current and previous clients are the
// same.
func (c *persistentClient) equalIDs(prev *persistentClient) (equal bool) {
return slices.Equal(c.IPs, prev.IPs) &&
slices.Equal(c.Subnets, prev.Subnets) &&
slices.EqualFunc(c.MACs, prev.MACs, slices.Equal[net.HardwareAddr]) &&
slices.Equal(c.ClientIDs, prev.ClientIDs)
}
// shallowClone returns a deep copy of the client, except upstreamConfig,
// safeSearchConf, SafeSearch fields, because it's difficult to copy them.
func (c *persistentClient) shallowClone() (clone *persistentClient) {
clone = &persistentClient{}
*clone = *c
clone.BlockedServices = c.BlockedServices.Clone()
clone.Tags = slices.Clone(c.Tags)
clone.Upstreams = slices.Clone(c.Upstreams)
clone.IPs = slices.Clone(c.IPs)
clone.Subnets = slices.Clone(c.Subnets)
clone.MACs = slices.Clone(c.MACs)
clone.ClientIDs = slices.Clone(c.ClientIDs)
return clone
}
// closeUpstreams closes the client-specific upstream config of c if any.
func (c *persistentClient) closeUpstreams() (err error) {
if c.upstreamConfig != nil {
if err = c.upstreamConfig.Close(); err != nil {
return fmt.Errorf("closing upstreams of client %q: %w", c.Name, err)
}
}
return nil
}
// setSafeSearch initializes and sets the safe search filter for this client.
func (c *persistentClient) setSafeSearch(
conf filtering.SafeSearchConfig,
cacheSize uint,
cacheTTL time.Duration,
) (err error) {
ss, err := safesearch.NewDefault(conf, fmt.Sprintf("client %q", c.Name), cacheSize, cacheTTL)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return err
}
c.SafeSearch = ss
return nil
}