diff --git a/prober/http.go b/prober/http.go index 757409da..b1c61b9d 100644 --- a/prober/http.go +++ b/prober/http.go @@ -145,28 +145,45 @@ type roundTripTrace struct { // transport is a custom transport keeping traces for each HTTP roundtrip. type transport struct { - Transport http.RoundTripper - logger log.Logger - traces []*roundTripTrace - current *roundTripTrace + Transport http.RoundTripper + NoServerNameTransport http.RoundTripper + firstHost string + logger log.Logger + traces []*roundTripTrace + current *roundTripTrace } -func newTransport(rt http.RoundTripper, logger log.Logger) *transport { +func newTransport(rt, noServerName http.RoundTripper, logger log.Logger) *transport { return &transport{ - Transport: rt, - logger: logger, - traces: []*roundTripTrace{}, + Transport: rt, + NoServerNameTransport: noServerName, + logger: logger, + traces: []*roundTripTrace{}, } } // RoundTrip switches to a new trace, then runs embedded RoundTripper. func (t *transport) RoundTrip(req *http.Request) (*http.Response, error) { + level.Info(t.logger).Log("msg", "Making HTTP request", "url", req.URL.String(), "host", req.Host) + trace := &roundTripTrace{} if req.URL.Scheme == "https" { trace.tls = true } t.current = trace t.traces = append(t.traces, trace) + + if t.firstHost == "" { + t.firstHost = req.URL.Host + } + + if t.firstHost != req.URL.Host { + // This is a redirect to something other than the initial host, + // so TLS ServerName should not be set. + level.Info(t.logger).Log("msg", "Address does not match first address, not sending TLS ServerName", "first", t.firstHost, "address", req.URL.Host) + return t.NoServerNameTransport.RoundTrip(req) + } + return t.Transport.RoundTrip(req) } @@ -290,6 +307,13 @@ func ProbeHTTP(ctx context.Context, target string, module config.Module, registr return false } + httpClientConfig.TLSConfig.ServerName = "" + noServerName, err := pconfig.NewRoundTripperFromConfig(httpClientConfig, "http_probe", true) + if err != nil { + level.Error(logger).Log("msg", "Error generating HTTP client without ServerName", "err", err) + return false + } + jar, err := cookiejar.New(&cookiejar.Options{PublicSuffixList: publicsuffix.List}) if err != nil { level.Error(logger).Log("msg", "Error generating cookiejar", "err", err) @@ -297,12 +321,13 @@ func ProbeHTTP(ctx context.Context, target string, module config.Module, registr } client.Jar = jar - // Inject transport that tracks trace for each redirect. - tt := newTransport(client.Transport, logger) + // Inject transport that tracks traces for each redirect, + // and does not set TLS ServerNames on redirect if needed. + tt := newTransport(client.Transport, noServerName, logger) client.Transport = tt client.CheckRedirect = func(r *http.Request, via []*http.Request) error { - level.Info(logger).Log("msg", "Received redirect", "url", r.URL.String()) + level.Info(logger).Log("msg", "Received redirect", "location", r.Response.Header.Get("Location")) redirects = len(via) if redirects > 10 || httpConfig.NoFollowRedirects { level.Info(logger).Log("msg", "Not following redirect") @@ -350,8 +375,6 @@ func ProbeHTTP(ctx context.Context, target string, module config.Module, registr request.Header.Set(key, value) } - level.Info(logger).Log("msg", "Making HTTP request", "url", request.URL.String(), "host", request.Host) - trace := &httptrace.ClientTrace{ DNSStart: tt.DNSStart, DNSDone: tt.DNSDone, diff --git a/prober/http_test.go b/prober/http_test.go index 5dc86579..637784f3 100644 --- a/prober/http_test.go +++ b/prober/http_test.go @@ -649,6 +649,27 @@ func TestHTTPUsesTargetAsTLSServerName(t *testing.T) { } } +func TestRedirectToTLSHostWorks(t *testing.T) { + if testing.Short() { + t.Skip("skipping network dependant test") + } + ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + http.Redirect(w, r, "https://prometheus.io", http.StatusFound) + })) + defer ts.Close() + + // Follow redirect, should succeed with 200. + registry := prometheus.NewRegistry() + testCTX, cancel := context.WithTimeout(context.Background(), 10*time.Second) + defer cancel() + result := ProbeHTTP(testCTX, ts.URL, + config.Module{Timeout: time.Second, HTTP: config.HTTPProbe{IPProtocolFallback: true}}, registry, log.NewNopLogger()) + if !result { + t.Fatalf("Redirect test failed unexpectedly") + } + +} + func TestHTTPPhases(t *testing.T) { ts := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { }))