feat: add plugin

dns/dns.go

@@ -13,6 +13,8 @@ import (
 	"time"
 
 	"github.com/fumiama/terasu"
+	"github.com/fumiama/terasu/dialer"
+	"github.com/fumiama/terasu/doh"
 	"github.com/fumiama/terasu/ip"
 	"github.com/sirupsen/logrus"
 )
@@ -24,15 +26,6 @@ var (
 	ErrSuccess = errors.New("success")
 )
 
-var dnsDialer = net.Dialer{
-	Timeout: time.Second * 4,
-}
-
-// SetTimeout ...
-func SetTimeout(t time.Duration) {
-	dnsDialer.Timeout = t
-}
-
 type dnsstat struct {
 	addr string
 	en   bool
@@ -173,9 +166,9 @@ func (ds *List) lookupHostDoH(ctx context.Context, host string) (hosts []string,
 			if !addr.enabled() || !addr.ishttps() { // disabled or is not DoH
 				continue
 			}
-			jr, err := lookupdoh(ctx, addr.addr, host)
+			jr, err := doh.LookupDoH(ctx, addr.addr, host)
 			if err == nil {
-				hosts = jr.hosts()
+				hosts = jr.Hosts()
 				if len(hosts) > 0 {
 					// this is a successful server, keep it
 					addr.keepit()
@@ -203,11 +196,11 @@ func (ds *List) lookupHostDoH(ctx context.Context, host string) (hosts []string,
 }
 
 // DialContext ...
-func (ds *List) DialContext(ctx context.Context, dialer *net.Dialer) (tlsConn *tls.Conn, err error) {
+func (ds *List) DialContext(ctx context.Context, d *net.Dialer) (tlsConn *tls.Conn, err error) {
 	err = ErrNoDNSAvailable
 
-	if dialer == nil {
-		dialer = &dnsDialer
+	if d == nil {
+		d = &dialer.DefaultDialer
 	}
 
 	ds.RLock()
@@ -220,16 +213,16 @@ func (ds *List) DialContext(ctx context.Context, dialer *net.Dialer) (tlsConn *t
 				continue
 			}
 			logrus.Debugln("[terasu.dns] -> dial", host, addr)
-			if dialer.Timeout != 0 {
+			if d.Timeout != 0 {
 				var cancel context.CancelFunc
-				ctx, cancel = context.WithTimeout(context.Background(), dialer.Timeout)
+				ctx, cancel = context.WithTimeout(context.Background(), d.Timeout)
 				defer cancel()
-			} else if !dialer.Deadline.IsZero() {
+			} else if !d.Deadline.IsZero() {
 				var cancel context.CancelFunc
-				ctx, cancel = context.WithDeadline(context.Background(), dialer.Deadline)
+				ctx, cancel = context.WithDeadline(context.Background(), d.Deadline)
 				defer cancel()
 			}
-			conn, err = dialer.DialContext(ctx, "tcp", addr.addr)
+			conn, err = d.DialContext(ctx, "tcp", addr.addr)
 			if err != nil {
 				logrus.Debugln("[terasu.dns] -- dial tcp", host, addr, "err:", err)
 				if !errors.Is(err, context.Canceled) &&
@@ -247,13 +240,13 @@ func (ds *List) DialContext(ctx context.Context, dialer *net.Dialer) (tlsConn *t
 				NextProtos: []string{"dns"},
 			})
 			// re-init ctx due to deadline settings in tcp dial
-			if dialer.Timeout != 0 {
+			if d.Timeout != 0 {
 				var cancel context.CancelFunc
-				ctx, cancel = context.WithTimeout(context.Background(), dialer.Timeout)
+				ctx, cancel = context.WithTimeout(context.Background(), d.Timeout)
 				defer cancel()
-			} else if !dialer.Deadline.IsZero() {
+			} else if !d.Deadline.IsZero() {
 				var cancel context.CancelFunc
-				ctx, cancel = context.WithDeadline(context.Background(), dialer.Deadline)
+				ctx, cancel = context.WithDeadline(context.Background(), d.Deadline)
 				defer cancel()
 			}
 			err = tlsConn.HandshakeContext(ctx)

dns/dns_test.go

@@ -4,11 +4,11 @@ import (
 	"context"
 	"crypto/tls"
 	"fmt"
-	"net"
 	"testing"
 	"time"
 
 	"github.com/fumiama/terasu"
+	"github.com/fumiama/terasu/dialer"
 	"github.com/fumiama/terasu/ip"
 )
 
@@ -110,7 +110,7 @@ func (ds *List) test() {
 				continue
 			}
 			fmt.Println("dial:", host, addr.addr)
-			conn, err := net.Dial("tcp", addr.addr)
+			conn, err := dialer.DefaultDialer.Dial("tcp", addr.addr)
 			if err != nil {
 				continue
 			}

dns/doh.go

@@ -1,179 +0,0 @@
-package dns
-
-import (
-	"context"
-	"crypto/tls"
-	"encoding/json"
-	"errors"
-	"net"
-	"net/http"
-	"net/url"
-	"strconv"
-	"strings"
-
-	"golang.org/x/net/http2"
-
-	"github.com/fumiama/terasu"
-	"github.com/fumiama/terasu/ip"
-)
-
-var (
-	// ErrEmptyHostAddress ...
-	ErrEmptyHostAddress = errors.New("empty host addr")
-)
-
-type recordType uint16
-
-const (
-	recordTypeNone recordType = 0
-	recordTypeA    recordType = 1
-	recordTypeAAAA recordType = 28
-)
-
-// dohjsonresponse represents the JSON response structure for DNS over HTTPS (DoH) queries.
-// It contains DNS query results and metadata about the response.
-type dohjsonresponse struct {
-	// Status indicates the DNS query status code (0 = NOERROR, etc.)
-	Status uint32
-	// TC indicates whether the response was truncated (true if truncated)
-	TC bool
-	// RD indicates whether recursion was requested in the query
-	RD bool
-	// RA indicates whether the server supports recursion
-	RA bool
-	// AD indicates whether the response was authenticated (DNSSEC)
-	AD bool
-	// CD indicates whether the client requested that DNSSEC validation be disabled
-	CD bool
-	// Question contains the DNS query question section with name and type
-	Question []struct {
-		// Name is the domain name being queried
-		Name string `json:"name"`
-		// Type is the DNS record type being requested (A, AAAA, etc.)
-		Type recordType `json:"type"`
-	}
-	// Answer contains the DNS response answer section with resource records
-	Answer []struct {
-		// Name is the domain name for this resource record
-		Name string `json:"name"`
-		// Type is the DNS record type (A, AAAA, etc.)
-		Type recordType `json:"type"`
-		// TTL is the time-to-live value for this resource record in seconds
-		TTL uint16
-		// Data is the textual representation of the resource record data
-		Data string `json:"data"`
-	}
-	// EdnsClientSubnet is the EDNS client subnet information for geolocation
-	EdnsClientSubnet string `json:"edns_client_subnet"`
-	// Comment is an optional comment field for additional information
-	Comment string
-}
-
-func (jr *dohjsonresponse) hosts() []string {
-	if len(jr.Answer) == 0 {
-		return nil
-	}
-	hosts := make([]string, 0, len(jr.Answer))
-	for _, ans := range jr.Answer {
-		if ans.Type == recordTypeA || ans.Type == recordTypeAAAA {
-			hosts = append(hosts, ans.Data)
-		}
-	}
-	return hosts
-}
-
-var trsHTTP2ClientWithSystemDNS = http.Client{
-	Transport: &http2.Transport{
-		DialTLSContext: func(ctx context.Context, network, addr string, cfg *tls.Config) (net.Conn, error) {
-			host, port, err := net.SplitHostPort(addr)
-			if err != nil {
-				return nil, err
-			}
-			addrs := lookupTable.Get(host)
-			if len(addrs) == 0 {
-				addrs, err = net.DefaultResolver.LookupHost(ctx, host)
-				if err != nil {
-					return nil, err
-				}
-				lookupTable.Set(host, addrs)
-			}
-			if len(addr) == 0 {
-				return nil, ErrEmptyHostAddress
-			}
-			var conn net.Conn
-			var tlsConn *tls.Conn
-			for _, a := range addrs {
-				conn, err = dnsDialer.DialContext(ctx, network, net.JoinHostPort(a, port))
-				if err != nil {
-					continue
-				}
-				tlsConn = tls.Client(terasu.NewConn(conn), cfg)
-				err = tlsConn.HandshakeContext(ctx)
-				if err == nil {
-					break
-				}
-				_ = tlsConn.Close()
-				tlsConn = nil
-				conn, err = dnsDialer.DialContext(ctx, network, net.JoinHostPort(a, port))
-				if err != nil {
-					continue
-				}
-				tlsConn = tls.Client(terasu.NewConn(conn), cfg)
-				err = tlsConn.HandshakeContext(ctx)
-				if err == nil {
-					break
-				}
-				_ = tlsConn.Close()
-				tlsConn = nil
-			}
-			return tlsConn, err
-		},
-	},
-}
-
-func lookupdoh(ctx context.Context, server, u string) (jr dohjsonresponse, err error) {
-	jr, err = lookupdohwithtype(ctx, server, u, preferreddohtype())
-	if err == nil {
-		return
-	}
-	if ip.IsIPv6Available {
-		jr, err = lookupdohwithtype(ctx, server, u, recordTypeA)
-	}
-	return
-}
-
-func lookupdohwithtype(ctx context.Context, server, u string, typ recordType) (jr dohjsonresponse, err error) {
-	sb := strings.Builder{}
-	sb.WriteString(server)
-	sb.WriteString("?name=")
-	sb.WriteString(url.QueryEscape(u))
-	if typ != recordTypeNone {
-		sb.WriteString("&type=")
-		sb.WriteString(strconv.Itoa(int(typ)))
-	}
-	req, err := http.NewRequestWithContext(ctx, "GET", sb.String(), nil)
-	if err != nil {
-		return
-	}
-	req.Header.Add("accept", "application/dns-json")
-	resp, err := trsHTTP2ClientWithSystemDNS.Do(req)
-	if err != nil {
-		return
-	}
-	defer resp.Body.Close()
-	err = json.NewDecoder(resp.Body).Decode(&jr)
-	if err != nil {
-		return
-	}
-	if jr.Status != 0 {
-		err = errors.New("comment: " + jr.Comment)
-	}
-	return
-}
-
-func preferreddohtype() recordType {
-	if ip.IsIPv6Available {
-		return recordTypeAAAA
-	}
-	return recordTypeA
-}

dns/tls.go

@@ -0,0 +1,19 @@
+package dns
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+
+	mtls "github.com/fumiama/terasu/tls"
+)
+
+// DialTLSContext fills http.Transport method with terasu and DNS
+func DialTLSContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	return DialTLSContextWithConfig(ctx, network, addr, nil)
+}
+
+// DialTLSContextWithConfig fills http2.Transport method with terasu and DNS
+func DialTLSContextWithConfig(ctx context.Context, network, addr string, cfg *tls.Config) (net.Conn, error) {
+	return mtls.DialTLSContextCL(ctx, network, addr, cfg, nil)
+}