refactor(netx): extract tlsdialer from dialer

internal/engine/netx/dialer/saver.go

@@ -2,11 +2,9 @@ package dialer
 
 import (
 	"context"
-	"crypto/tls"
 	"net"
 	"time"
 
-	"github.com/ooni/probe-cli/v3/internal/engine/internal/tlsx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/trace"
 )
@@ -33,42 +31,6 @@ func (d SaverDialer) DialContext(ctx context.Context, network, address string) (
 	return conn, err
 }
 
-// SaverTLSHandshaker saves events occurring during the handshake
-type SaverTLSHandshaker struct {
-	TLSHandshaker
-	Saver *trace.Saver
-}
-
-// Handshake implements TLSHandshaker.Handshake
-func (h SaverTLSHandshaker) Handshake(
-	ctx context.Context, conn net.Conn, config *tls.Config,
-) (net.Conn, tls.ConnectionState, error) {
-	start := time.Now()
-	h.Saver.Write(trace.Event{
-		Name:          "tls_handshake_start",
-		NoTLSVerify:   config.InsecureSkipVerify,
-		TLSNextProtos: config.NextProtos,
-		TLSServerName: config.ServerName,
-		Time:          start,
-	})
-	tlsconn, state, err := h.TLSHandshaker.Handshake(ctx, conn, config)
-	stop := time.Now()
-	h.Saver.Write(trace.Event{
-		Duration:           stop.Sub(start),
-		Err:                err,
-		Name:               "tls_handshake_done",
-		NoTLSVerify:        config.InsecureSkipVerify,
-		TLSCipherSuite:     tlsx.CipherSuiteString(state.CipherSuite),
-		TLSNegotiatedProto: state.NegotiatedProtocol,
-		TLSNextProtos:      config.NextProtos,
-		TLSPeerCerts:       trace.PeerCerts(state, err),
-		TLSServerName:      config.ServerName,
-		TLSVersion:         tlsx.VersionString(state.Version),
-		Time:               stop,
-	})
-	return tlsconn, state, err
-}
-
 // SaverConnDialer wraps the returned connection such that we
 // collect all the read/write events that occur.
 type SaverConnDialer struct {
@@ -121,5 +83,4 @@ func (c saverConn) Write(p []byte) (int, error) {
 }
 
 var _ Dialer = SaverDialer{}
-var _ TLSHandshaker = SaverTLSHandshaker{}
 var _ net.Conn = saverConn{}