awl/pkg/resolvers/DNSCrypt.go

62 lines
1.2 KiB
Go

// SPDX-License-Identifier: BSD-3-Clause
package resolvers
import (
"fmt"
"time"
"git.froth.zone/sam/awl/pkg/util"
"github.com/ameshkov/dnscrypt/v2"
"github.com/miekg/dns"
)
// DNSCryptResolver is for making DNSCrypt queries.
type DNSCryptResolver struct {
opts util.Options
}
var _ Resolver = (*DNSCryptResolver)(nil)
// LookUp performs a DNS query.
func (r *DNSCryptResolver) LookUp(msg *dns.Msg) (util.Response, error) {
client := dnscrypt.Client{
Timeout: r.opts.Request.Timeout,
UDPSize: 1232,
}
if r.opts.TCP || r.opts.TLS {
client.Net = tcp
} else {
client.Net = udp
}
switch {
case r.opts.IPv4:
client.Net += "4"
case r.opts.IPv6:
client.Net += "6"
}
r.opts.Logger.Debug("Using", client.Net, "for making the request")
resolverInf, err := client.Dial(r.opts.Request.Server)
if err != nil {
return util.Response{}, fmt.Errorf("dnscrypt: dial: %w", err)
}
now := time.Now()
res, err := client.Exchange(msg, resolverInf)
rtt := time.Since(now)
if err != nil {
return util.Response{}, fmt.Errorf("dnscrypt: exchange: %w", err)
}
r.opts.Logger.Info("Request successful")
return util.Response{
DNS: res,
RTT: rtt,
}, nil
}