Merge pull request #6638 from feeeei/feat/images-url-to-b64json-backfill

feat(images): 账户开关将生图结果 url 下载回填为 b64_json

backend/internal/repository/http_upstream.go

@@ -213,7 +213,7 @@ func (s *httpUpstreamService) Do(req *http.Request, proxyURL string, accountID i
 	}
 
 	// 执行请求
-	client := httpClientForUpstreamRequest(entry.client, req)
+	client := s.httpClientForUpstreamRequest(entry.client, req)
 	client = httpClientWithGrokAccessDeniedFallback(client)
 	resp, err := servertiming.Do(client, req)
 	if err != nil {
@@ -277,7 +277,7 @@ func (s *httpUpstreamService) DoWithTLS(req *http.Request, proxyURL string, acco
 		return nil, err
 	}
 
-	client := httpClientForUpstreamRequest(entry.client, req)
+	client := s.httpClientForUpstreamRequest(entry.client, req)
 	client = httpClientWithGrokAccessDeniedFallback(client)
 	resp, err := servertiming.Do(client, req)
 	if err != nil {
@@ -297,15 +297,27 @@ func (s *httpUpstreamService) DoWithTLS(req *http.Request, proxyURL string, acco
 	return resp, nil
 }
 
-func httpClientForUpstreamRequest(client *http.Client, req *http.Request) *http.Client {
-	if client == nil || req == nil || !service.HTTPUpstreamRedirectsDisabled(req.Context()) {
+// httpClientForUpstreamRequest 按请求上下文的标记派生客户端：禁用重定向，或对重定向的每一跳做主机校验。
+// 派生的克隆与缓存客户端共享 Transport；未打标记时原样返回。
+func (s *httpUpstreamService) httpClientForUpstreamRequest(client *http.Client, req *http.Request) *http.Client {
+	if client == nil || req == nil {
 		return client
 	}
-	clone := *client
-	clone.CheckRedirect = func(*http.Request, []*http.Request) error {
-		return http.ErrUseLastResponse
+	ctx := req.Context()
+	switch {
+	case service.HTTPUpstreamRedirectsDisabled(ctx):
+		clone := *client
+		clone.CheckRedirect = func(*http.Request, []*http.Request) error {
+			return http.ErrUseLastResponse
+		}
+		return &clone
+	case service.HTTPUpstreamPublicHostsOnly(ctx) && client.CheckRedirect == nil:
+		clone := *client
+		clone.CheckRedirect = s.redirectChecker
+		return &clone
+	default:
+		return client
 	}
-	return &clone
 }
 
 // grokAccessDeniedFallbackTransport preserves the subscription CLI proxy as
@@ -587,8 +599,11 @@ func (s *httpUpstreamService) shouldValidateResolvedIP() bool {
 	return !s.cfg.Security.URLAllowlist.AllowPrivateHosts
 }
 
+// validateRequestHost 校验请求主机的解析结果不落在回环、私网、链路本地或未指定地址。
+// 是否全局启用由 security.url_allowlist 决定；带 WithHTTPUpstreamPublicHostsOnly 标记的请求无论配置如何都校验。
 func (s *httpUpstreamService) validateRequestHost(req *http.Request) error {
-	if !s.shouldValidateResolvedIP() {
+	publicHostsOnly := req != nil && service.HTTPUpstreamPublicHostsOnly(req.Context())
+	if !s.shouldValidateResolvedIP() && !publicHostsOnly {
 		return nil
 	}
 	if req == nil || req.URL == nil {

backend/internal/repository/http_upstream_test.go

@@ -961,3 +961,63 @@ func hasEntry(svc *httpUpstreamService, target *upstreamClientEntry) bool {
 	}
 	return false
 }
+
+func TestHTTPUpstreamDoPublicHostsOnlyRejectsPrivateDestinationBeforeConnecting(t *testing.T) {
+	var calls atomic.Int64
+	target := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+		calls.Add(1)
+		w.WriteHeader(http.StatusOK)
+	}))
+	t.Cleanup(target.Close)
+
+	upstream := NewHTTPUpstream(nil)
+
+	plain, err := http.NewRequestWithContext(t.Context(), http.MethodGet, target.URL, nil)
+	require.NoError(t, err)
+	resp, err := upstream.Do(plain, "", 1, 1)
+	require.NoError(t, err)
+	require.NoError(t, resp.Body.Close())
+	require.Equal(t, int64(1), calls.Load(), "loopback stays reachable for requests without the marker")
+
+	guarded, err := http.NewRequestWithContext(service.WithHTTPUpstreamPublicHostsOnly(t.Context()), http.MethodGet, target.URL, nil)
+	require.NoError(t, err)
+	resp, err = upstream.Do(guarded, "", 1, 1)
+	require.Error(t, err)
+	require.Nil(t, resp)
+	require.Contains(t, err.Error(), "not allowed")
+	require.Equal(t, int64(1), calls.Load(), "marked request must be rejected before any connection is made")
+}
+
+func TestHTTPUpstreamPublicHostsOnlyValidatesEveryRedirectHop(t *testing.T) {
+	upstream, ok := NewHTTPUpstream(nil).(*httpUpstreamService)
+	require.True(t, ok)
+	base := &http.Client{}
+
+	plain, err := http.NewRequestWithContext(t.Context(), http.MethodGet, "https://cdn.example.com/a.png", nil)
+	require.NoError(t, err)
+	require.Same(t, base, upstream.httpClientForUpstreamRequest(base, plain))
+
+	guarded, err := http.NewRequestWithContext(service.WithHTTPUpstreamPublicHostsOnly(t.Context()), http.MethodGet, "https://cdn.example.com/a.png", nil)
+	require.NoError(t, err)
+	client := upstream.httpClientForUpstreamRequest(base, guarded)
+	require.NotSame(t, base, client)
+	require.NotNil(t, client.CheckRedirect)
+	require.Nil(t, base.CheckRedirect, "the cached client must stay untouched")
+
+	via := []*http.Request{guarded}
+	for _, hop := range []string{
+		"http://127.0.0.1:8080/a.png",
+		"http://[::1]:8080/a.png",
+		"http://10.0.0.8/a.png",
+		"http://169.254.169.254/latest/meta-data/",
+		"http://0.0.0.0/a.png",
+	} {
+		hopReq, err := http.NewRequestWithContext(guarded.Context(), http.MethodGet, hop, nil)
+		require.NoError(t, err)
+		require.Error(t, client.CheckRedirect(hopReq, via), "hop=%s", hop)
+	}
+	publicHop, err := http.NewRequestWithContext(guarded.Context(), http.MethodGet, "http://93.184.216.34/a.png", nil)
+	require.NoError(t, err)
+	require.NoError(t, client.CheckRedirect(publicHop, via))
+	require.Error(t, client.CheckRedirect(publicHop, make([]*http.Request, 10)), "redirect chain stays capped")
+}