AdGuardHome/internal/dnsforward/beforerequest.go

54 lines
1.2 KiB
Go

package dnsforward
import (
"encoding/binary"
"fmt"
"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
"github.com/AdguardTeam/dnsproxy/proxy"
"github.com/AdguardTeam/golibs/log"
"github.com/miekg/dns"
)
// type check
var _ proxy.BeforeRequestHandler = (*Server)(nil)
// HandleBefore is the handler that is called before any other processing,
// including logs. It performs access checks and puts the client ID, if there
// is one, into the server's cache.
//
// TODO(e.burkov): Write tests.
func (s *Server) HandleBefore(
_ *proxy.Proxy,
pctx *proxy.DNSContext,
) (err error) {
clientID, err := s.clientIDFromDNSContext(pctx)
if err != nil {
return fmt.Errorf("getting clientid: %w", err)
}
blocked, _ := s.IsBlockedClient(pctx.Addr.Addr(), clientID)
if blocked {
return s.preBlockedResponse(pctx)
}
if len(pctx.Req.Question) == 1 {
q := pctx.Req.Question[0]
qt := q.Qtype
host := aghnet.NormalizeDomain(q.Name)
if s.access.isBlockedHost(host, qt) {
log.Debug("access: request %s %s is in access blocklist", dns.Type(qt), host)
return s.preBlockedResponse(pctx)
}
}
if clientID != "" {
key := [8]byte{}
binary.BigEndian.PutUint64(key[:], pctx.RequestID)
s.clientIDCache.Set(key[:], []byte(clientID))
}
return nil
}