Patch up HTTP clients

cmd/syncthing/main.go

@@ -30,6 +30,7 @@ import (
 	"github.com/syncthing/syncthing/lib/config"
 	"github.com/syncthing/syncthing/lib/connections"
 	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/dialer"
 	"github.com/syncthing/syncthing/lib/discover"
 	"github.com/syncthing/syncthing/lib/events"
 	"github.com/syncthing/syncthing/lib/logger"
@@ -432,6 +433,8 @@ func upgradeViaRest() error {
 	r.Header.Set("X-API-Key", cfg.GUI().APIKey)
 
 	tr := &http.Transport{
+		Dial:            dialer.Dial,
+		Proxy:           http.ProxyFromEnvironment,
 		TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
 	}
 	client := &http.Client{

lib/dialer/dialer.go

@@ -8,6 +8,7 @@ package dialer
 
 import (
 	"net"
+	"net/http"
 	"os"
 	"strings"
 	"time"
@@ -26,6 +27,12 @@ var (
 func init() {
 	l.SetDebug("dialer", strings.Contains(os.Getenv("STTRACE"), "dialer") || os.Getenv("STTRACE") == "all")
 	if usingProxy {
+		http.DefaultTransport = &http.Transport{
+			Dial:                Dial,
+			Proxy:               http.ProxyFromEnvironment,
+			TLSHandshakeTimeout: 10 * time.Second,
+		}
+
 		// Defer this, so that logging gets setup.
 		go func() {
 			time.Sleep(500 * time.Millisecond)

lib/discover/global.go

@@ -18,6 +18,7 @@ import (
 	stdsync "sync"
 	"time"
 
+	"github.com/syncthing/syncthing/lib/dialer"
 	"github.com/syncthing/syncthing/lib/events"
 	"github.com/syncthing/syncthing/lib/protocol"
 )
@@ -73,6 +74,8 @@ func NewGlobal(server string, cert tls.Certificate, addrList AddressLister, rela
 	// certificate depending on the insecure setting.
 	var announceClient httpClient = &http.Client{
 		Transport: &http.Transport{
+			Dial:  dialer.Dial,
+			Proxy: http.ProxyFromEnvironment,
 			TLSClientConfig: &tls.Config{
 				InsecureSkipVerify: opts.insecure,
 				Certificates:       []tls.Certificate{cert},
@@ -87,6 +90,8 @@ func NewGlobal(server string, cert tls.Certificate, addrList AddressLister, rela
 	// certificate here, so lets not include it. May be insecure if requested.
 	var queryClient httpClient = &http.Client{
 		Transport: &http.Transport{
+			Dial:  dialer.Dial,
+			Proxy: http.ProxyFromEnvironment,
 			TLSClientConfig: &tls.Config{
 				InsecureSkipVerify: opts.insecure,
 			},

lib/rc/rc.go

@@ -26,6 +26,7 @@ import (
 	"time"
 
 	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/dialer"
 	"github.com/syncthing/syncthing/lib/protocol"
 	"github.com/syncthing/syncthing/lib/sync"
 )
@@ -156,6 +157,8 @@ func (p *Process) Get(path string) ([]byte, error) {
 	client := &http.Client{
 		Timeout: 30 * time.Second,
 		Transport: &http.Transport{
+			Dial:              dialer.Dial,
+			Proxy:             http.ProxyFromEnvironment,
 			DisableKeepAlives: true,
 		},
 	}

lib/upgrade/upgrade_supported.go

@@ -26,6 +26,7 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/syncthing/syncthing/lib/dialer"
 	"github.com/syncthing/syncthing/lib/signature"
 )
 
@@ -38,6 +39,8 @@ const DisabledByCompilation = false
 // binary contents before accepting the upgrade.
 var insecureHTTP = &http.Client{
 	Transport: &http.Transport{
+		Dial:  dialer.Dial,
+		Proxy: http.ProxyFromEnvironment,
 		TLSClientConfig: &tls.Config{
 			InsecureSkipVerify: true,
 		},