awl/query/HTTPS.go
Sam Therapy 8a3afa261a
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refactor: make more tests table driven
Signed-off-by: Sam Therapy <sam@samtherapy.net>
2022-09-21 14:07:00 +02:00

89 lines
1.9 KiB
Go

// SPDX-License-Identifier: BSD-3-Clause
package query
import (
"bytes"
"fmt"
"io"
"net/http"
"time"
"git.froth.zone/sam/awl/util"
"github.com/miekg/dns"
)
// HTTPSResolver is for DNS-over-HTTPS queries.
type HTTPSResolver struct {
opts util.Options
}
var _ Resolver = (*HTTPSResolver)(nil)
// LookUp performs a DNS query.
func (r *HTTPSResolver) LookUp(msg *dns.Msg) (util.Response, error) {
var resp util.Response
httpR := &http.Client{
Timeout: r.opts.Request.Timeout,
}
buf, err := msg.Pack()
if err != nil {
return util.Response{}, fmt.Errorf("doh: packing: %w", err)
}
r.opts.Logger.Debug("https: sending HTTPS request")
req, err := http.NewRequest("POST", r.opts.Request.Server, bytes.NewBuffer(buf))
if err != nil {
return util.Response{}, fmt.Errorf("doh: request creation: %w", err)
}
req.Header.Set("Content-Type", "application/dns-message")
req.Header.Set("Accept", "application/dns-message")
now := time.Now()
res, err := httpR.Do(req)
resp.RTT = time.Since(now)
if err != nil {
return util.Response{}, fmt.Errorf("doh: HTTP request: %w", err)
}
if res.StatusCode != http.StatusOK {
return util.Response{}, &ErrHTTPStatus{res.StatusCode}
}
r.opts.Logger.Debug("https: reading response")
fullRes, err := io.ReadAll(res.Body)
if err != nil {
return util.Response{}, fmt.Errorf("doh: body read: %w", err)
}
err = res.Body.Close()
if err != nil {
return util.Response{}, fmt.Errorf("doh: body close: %w", err)
}
r.opts.Logger.Debug("https: unpacking response")
resp.DNS = &dns.Msg{}
err = resp.DNS.Unpack(fullRes)
if err != nil {
return util.Response{}, fmt.Errorf("doh: dns message unpack: %w", err)
}
return resp, nil
}
// ErrHTTPStatus is returned when DoH returns a bad status code.
type ErrHTTPStatus struct {
code int
}
func (e *ErrHTTPStatus) Error() string {
return fmt.Sprintf("doh server responded with HTTP %d", e.code)
}