Merge pull request #760 from mlipscombe/issue-688

fix: make `tls_client` configuration work in `target.smtp` block, fixes foxcpp/maddy#688

internal/target/smtp/smtp_downstream.go

@@ -57,7 +57,7 @@ type Downstream struct {
 	hostname    string
 	endpoints   []config.Endpoint
 	saslFactory saslClientFactory
-	tlsConfig   tls.Config
+	tlsConfig   *tls.Config
 
 	connectTimeout    time.Duration
 	commandTimeout    time.Duration
@@ -121,7 +121,7 @@ func (u *Downstream) Init(cfg *config.Map) error {
 		return nil, nil
 	}, saslAuthDirective, &u.saslFactory)
 	cfg.Custom("tls_client", true, false, func() (interface{}, error) {
-		return tls.Config{}, nil
+		return &tls.Config{}, nil
 	}, tls2.TLSClientBlock, &u.tlsConfig)
 	cfg.Duration("connect_timeout", false, false, 5*time.Minute, &u.connectTimeout)
 	cfg.Duration("command_timeout", false, false, 5*time.Minute, &u.commandTimeout)
@@ -229,9 +229,9 @@ func (d *delivery) connect(ctx context.Context) error {
 	for _, endp := range d.u.endpoints {
 		var err error
 		if d.u.lmtp {
-			_, err = conn.ConnectLMTP(ctx, endp, d.u.starttls, &d.u.tlsConfig)
+			_, err = conn.ConnectLMTP(ctx, endp, d.u.starttls, d.u.tlsConfig)
 		} else {
-			_, err = conn.Connect(ctx, endp, d.u.starttls, &d.u.tlsConfig)
+			_, err = conn.Connect(ctx, endp, d.u.starttls, d.u.tlsConfig)
 		}
 		if err != nil {
 			if len(d.u.endpoints) != 1 {

internal/target/smtp/smtp_downstream_test.go

@@ -221,7 +221,7 @@ func TestDownstreamDelivery_StartTLS(t *testing.T) {
 				Port:   testPort,
 			},
 		},
-		tlsConfig: *clientCfg.Clone(),
+		tlsConfig: clientCfg.Clone(),
 		starttls:  true,
 		log:       testutils.Logger(t, "target.smtp"),
 	}