78 lines
2.1 KiB
Go
78 lines
2.1 KiB
Go
package netproxy
|
|
|
|
import (
|
|
"context"
|
|
"io"
|
|
"net"
|
|
"net/http"
|
|
"net/http/httptest"
|
|
"net/url"
|
|
"strings"
|
|
"sync"
|
|
"testing"
|
|
)
|
|
|
|
// A host whose IPv6 address takes the connection and closes it at once
|
|
// (a TUN that can't carry IPv6) is reached over IPv4, the first request
|
|
// included, and dialed over IPv4 from then on.
|
|
func TestIPv4Fallback(t *testing.T) {
|
|
v6, err := net.Listen("tcp6", "[::1]:0")
|
|
if err != nil {
|
|
t.Skip("no ::1:", err)
|
|
}
|
|
defer v6.Close()
|
|
go func() {
|
|
for {
|
|
c, err := v6.Accept()
|
|
if err != nil {
|
|
return
|
|
}
|
|
c.Close()
|
|
}
|
|
}()
|
|
srv := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
b, _ := io.ReadAll(r.Body)
|
|
io.WriteString(w, r.Method+" "+string(b))
|
|
}))
|
|
srv.EnableHTTP2 = true
|
|
srv.StartTLS()
|
|
defer srv.Close()
|
|
t.Cleanup(func() { v4Only.Lock(); v4Only.at = nil; v4Only.Unlock() })
|
|
|
|
var mu sync.Mutex
|
|
var dials []string
|
|
var d net.Dialer
|
|
base := &http.Transport{
|
|
Proxy: func(*http.Request) (*url.URL, error) { return nil, nil },
|
|
TLSClientConfig: srv.Client().Transport.(*http.Transport).TLSClientConfig.Clone(),
|
|
ForceAttemptHTTP2: true,
|
|
// example.com resolves to [::1] first, as a dual-stack name does
|
|
DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
|
|
mu.Lock()
|
|
dials = append(dials, network)
|
|
mu.Unlock()
|
|
if network == "tcp4" {
|
|
return d.DialContext(ctx, "tcp4", srv.Listener.Addr().String())
|
|
}
|
|
return d.DialContext(ctx, "tcp", v6.Addr().String())
|
|
},
|
|
}
|
|
c := &http.Client{Transport: Dispatch(base)}
|
|
for i, method := range []string{"GET", "POST"} {
|
|
req, _ := http.NewRequest(method, "https://example.com/", strings.NewReader("body"))
|
|
res, err := c.Do(req)
|
|
if err != nil {
|
|
t.Fatalf("request %d: %v (dials %v)", i, err, dials)
|
|
}
|
|
b, _ := io.ReadAll(res.Body)
|
|
res.Body.Close()
|
|
if string(b) != method+" body" || res.ProtoMajor != 2 {
|
|
t.Fatalf("request %d: %q over %s", i, b, res.Proto)
|
|
}
|
|
base.CloseIdleConnections()
|
|
}
|
|
if got := strings.Join(dials, ","); got != "tcp,tcp4,tcp4" {
|
|
t.Fatalf("dials %s, want tcp,tcp4,tcp4", got)
|
|
}
|
|
}
|