Request interceptor: block redirects backport to v8.5.x #334 (#335)

* Request interceptor: block redirects

(cherry picked from commit 77865143a3)
(cherry picked from commit 8e431c40a99669e1c9f52758d1c2e17ed0a51950)

* handle location missing

(cherry picked from commit fa93edf698)
(cherry picked from commit 4dea307274b415d9ae00ae0c908c7ca5b30be7f1)

* Update pkg/infra/httpclient/httpclientprovider/host_redirect_validation_middleware.go

Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>
(cherry picked from commit 801b0b77110d1f366e2f692eb2c77537f8834879)

* Update pkg/infra/httpclient/httpclientprovider/host_redirect_validation_middleware.go

Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>
(cherry picked from commit 8e1545f104f9f934ebce32ce6ed00f22adb25f38)

* linter

(cherry picked from commit 0e065f0f78e30901ac01b0cf1a9b31944ca4b12c)

* fixes tests

(cherry picked from commit a91a849df1)
(cherry picked from commit aea9009f8a7e155a17e9e89d090451f191cf1b30)

Co-authored-by: Leonard Gram <leo@xlson.com>

pkg/infra/httpclient/httpclientprovider/host_redirect_validation_middleware.go

@@ -0,0 +1,37 @@
+package httpclientprovider
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/grafana/grafana/pkg/models"
+
+	sdkhttpclient "github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
+)
+
+const HostRedirectValidationMiddlewareName = "host-redirect-validation"
+
+func RedirectLimitMiddleware(reqValidator models.PluginRequestValidator) sdkhttpclient.Middleware {
+	return sdkhttpclient.NamedMiddlewareFunc(HostRedirectValidationMiddlewareName, func(opts sdkhttpclient.Options, next http.RoundTripper) http.RoundTripper {
+		return sdkhttpclient.RoundTripperFunc(func(req *http.Request) (*http.Response, error) {
+			res, err := next.RoundTrip(req)
+			if err != nil {
+				return nil, err
+			}
+			if res.StatusCode >= 300 && res.StatusCode < 400 {
+				location, locationErr := res.Location()
+				if errors.Is(locationErr, http.ErrNoLocation) {
+					return res, nil
+				}
+				if locationErr != nil {
+					return nil, locationErr
+				}
+
+				if validationErr := reqValidator.Validate(location.String(), nil); validationErr != nil {
+					return nil, validationErr
+				}
+			}
+			return res, nil
+		})
+	})
+}

pkg/infra/httpclient/httpclientprovider/http_client_provider.go

@@ -5,6 +5,8 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/grafana/grafana/pkg/models"
+
 	sdkhttpclient "github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/infra/metrics/metricutil"
@@ -16,7 +18,7 @@ import (
 var newProviderFunc = sdkhttpclient.NewProvider
 
 // New creates a new HTTP client provider with pre-configured middlewares.
-func New(cfg *setting.Cfg, tracer tracing.Tracer) *sdkhttpclient.Provider {
+func New(cfg *setting.Cfg, validator models.PluginRequestValidator, tracer tracing.Tracer) *sdkhttpclient.Provider {
 	logger := log.New("httpclient")
 	userAgent := fmt.Sprintf("Grafana/%s", cfg.BuildVersion)
 
@@ -27,6 +29,7 @@ func New(cfg *setting.Cfg, tracer tracing.Tracer) *sdkhttpclient.Provider {
 		sdkhttpclient.BasicAuthenticationMiddleware(),
 		sdkhttpclient.CustomHeadersMiddleware(),
 		ResponseLimitMiddleware(cfg.ResponseLimit),
+		RedirectLimitMiddleware(validator),
 	}
 
 	if cfg.SigV4AuthEnabled {

pkg/infra/httpclient/httpclientprovider/http_client_provider_test.go

@@ -3,6 +3,8 @@ package httpclientprovider
 import (
 	"testing"
 
+	"github.com/grafana/grafana/pkg/services/validations"
+
 	sdkhttpclient "github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
 	"github.com/grafana/grafana/pkg/infra/tracing"
 	"github.com/grafana/grafana/pkg/setting"
@@ -22,10 +24,10 @@ func TestHTTPClientProvider(t *testing.T) {
 		})
 		tracer, err := tracing.InitializeTracerForTest()
 		require.NoError(t, err)
-		_ = New(&setting.Cfg{SigV4AuthEnabled: false}, tracer)
+		_ = New(&setting.Cfg{SigV4AuthEnabled: false}, &validations.OSSPluginRequestValidator{}, tracer)
 		require.Len(t, providerOpts, 1)
 		o := providerOpts[0]
-		require.Len(t, o.Middlewares, 6)
+		require.Len(t, o.Middlewares, 7)
 		require.Equal(t, TracingMiddlewareName, o.Middlewares[0].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, DataSourceMetricsMiddlewareName, o.Middlewares[1].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, SetUserAgentMiddlewareName, o.Middlewares[2].(sdkhttpclient.MiddlewareName).MiddlewareName())
@@ -46,16 +48,16 @@ func TestHTTPClientProvider(t *testing.T) {
 		})
 		tracer, err := tracing.InitializeTracerForTest()
 		require.NoError(t, err)
-		_ = New(&setting.Cfg{SigV4AuthEnabled: true}, tracer)
+		_ = New(&setting.Cfg{SigV4AuthEnabled: true}, &validations.OSSPluginRequestValidator{}, tracer)
 		require.Len(t, providerOpts, 1)
 		o := providerOpts[0]
-		require.Len(t, o.Middlewares, 7)
+		require.Len(t, o.Middlewares, 8)
 		require.Equal(t, TracingMiddlewareName, o.Middlewares[0].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, DataSourceMetricsMiddlewareName, o.Middlewares[1].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, SetUserAgentMiddlewareName, o.Middlewares[2].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, sdkhttpclient.BasicAuthenticationMiddlewareName, o.Middlewares[3].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, sdkhttpclient.CustomHeadersMiddlewareName, o.Middlewares[4].(sdkhttpclient.MiddlewareName).MiddlewareName())
 		require.Equal(t, ResponseLimitMiddlewareName, o.Middlewares[5].(sdkhttpclient.MiddlewareName).MiddlewareName())
-		require.Equal(t, SigV4MiddlewareName, o.Middlewares[6].(sdkhttpclient.MiddlewareName).MiddlewareName())
+		require.Equal(t, SigV4MiddlewareName, o.Middlewares[7].(sdkhttpclient.MiddlewareName).MiddlewareName())
 	})
 }