fix(gateway): AUTO scope grants all models — restrict to routing mode only

A key with scope=[AUTO] could previously:
1. request ANY concrete model id directly (hasScopeModel/checkModelScope
   treated AUTO as a wildcard)
2. see the full 56-model list on /v1/models (intersectModels considered
   AUTO as grant-everything)

AUTO now only authorizes the AUTO routing mode. Direct requests to a
specific model require an explicit scope entry.

Also carries agentrouter.lua WAF fingerprint headers (Origin/Referer/
X-Requested-With) already staged on this branch.

Tests: TestHasScopeModelWithSourcePrefix updated; full suite green.

internal/gateway/chat.go

@@ -115,13 +115,15 @@ func (g *Gateway) resolveCands(ctx context.Context, req *chatRequest) ([]*provid
 }
 
 // filterCandsByModels keeps only providers exposing at least one model of the
-// scope (used for user keys with a restricted model scope). An "AUTO" scope
-// entry means the key is allowed to use any model. Scope entries with a
-// Source pinned to a specific upstream narrow the candidates to that source
+// scope (used for user keys with a restricted model scope). Scope entries with
+// a Source pinned to a specific upstream narrow the candidates to that source
 // for the matching model.
+//
+// An "AUTO" scope entry only allows the AUTO routing mode; it does NOT grant
+// access to specific models.
 func filterCandsByModels(cands []*provider.Provider, allow []config.ModelScope) []*provider.Provider {
 	for _, m := range allow {
-		if m.Model == "" || strings.EqualFold(m.Model, "AUTO") {
+		if m.Model == "" {
 			return cands
 		}
 	}
@@ -152,20 +154,18 @@ func filterCandsByModels(cands []*provider.Provider, allow []config.ModelScope)
 	return out
 }
 
-// intersectModels restricts a model list to the scope (preserving order). An
-// "AUTO" scope entry grants every model.
+// intersectModels restricts a model list to the scope (preserving order).
+// An "AUTO" scope entry only allows the AUTO routing mode; it does NOT grant
+// every model.
 func intersectModels(models []string, allow []config.ModelScope) []string {
 	allowed := make(map[string]bool, len(allow))
-	any := false
 	for _, m := range allow {
-		if m.Model == "" || strings.EqualFold(m.Model, "AUTO") {
-			any = true
-			break
+		if m.Model == "" {
+			return models
 		}
+		if !strings.EqualFold(m.Model, "AUTO") {
 			allowed[m.Model] = true
 		}
-	if any {
-		return models
 	}
 	out := make([]string, 0, len(models))
 	seen := map[string]bool{}
@@ -179,24 +179,16 @@ func intersectModels(models []string, allow []config.ModelScope) []string {
 }
 
 // checkModelScope validates the effective model against the key's model scope
-// and token quota. Returns an error message when rejected. A scope entry with
-// model "AUTO" grants all models; its quota caps the key's total tokens.
+// and token quota. Returns an error message when rejected.
+//
+// A scope entry with model "AUTO" only allows requests where the effective
+// model is AUTO (the routing mode). It does NOT grant access to specific model
+// ids — that requires an explicit scope entry for the model.
 func (g *Gateway) checkModelScope(ctx context.Context, model string) string {
 	allow := g.allowedModels(ctx)
 	if allow == nil {
 		return ""
 	}
-	for _, sc := range allow {
-		if sc.Model != "" && strings.EqualFold(sc.Model, "AUTO") {
-			if sc.TokenQuota > 0 {
-				used := g.scopeTokens(ctx, sc)
-				if used >= sc.TokenQuota {
-					return fmt.Sprintf("token quota exceeded (%d/%d)", used, sc.TokenQuota)
-				}
-			}
-			return ""
-		}
-	}
 	for _, sc := range allow {
 		if sc.Model != model {
 			continue
@@ -229,12 +221,15 @@ func (g *Gateway) scopeTokens(ctx context.Context, sc config.ModelScope) int64 {
 // source that actually serves the bare model (via Registry.EffectiveModel), so
 // model ids that themselves contain separators (e.g. "deepseek-v4-flash-free")
 // are never corrupted (P10-2).
+//
+// A scope entry with model "AUTO" only matches the literal AUTO routing mode;
+// it does NOT grant access to specific model ids.
 func (g *Gateway) hasScopeModel(list []config.ModelScope, s string) bool {
 	if r := g.core.Registry(); r != nil {
 		s = r.EffectiveModel(s)
 	}
 	for _, x := range list {
-		if x.Model == s || (x.Model != "" && strings.EqualFold(x.Model, "AUTO")) {
+		if x.Model == s {
 			return true
 		}
 	}

internal/gateway/gateway_test.go

@@ -670,8 +670,11 @@ func TestHasScopeModelWithSourcePrefix(t *testing.T) {
 	if g.hasScopeModel(scope, "deepseek-v4-flash-free-extra") {
 		t.Error("hasScopeModel returned true for unrelated model")
 	}
-	if !g.hasScopeModel([]config.ModelScope{{Model: "AUTO"}}, "zen:anything") {
-		t.Error("AUTO scope should allow any prefixed model")
+	if g.hasScopeModel([]config.ModelScope{{Model: "AUTO"}}, "zen:deepseek-v4-flash-free") {
+		t.Error("AUTO scope must NOT grant specific model ids even with prefix")
+	}
+	if g.hasScopeModel([]config.ModelScope{{Model: "AUTO"}}, "deepseek-v4-pro") {
+		t.Error("AUTO scope must NOT grant specific model ids")
 	}
 }
 

internal/lua/adapters/agentrouter.lua

@@ -5,10 +5,12 @@ adapter.version = "1.0.0"
 adapter.endpoint = "/chat/completions"
 adapter.headers = {}
 
--- AgentRouter 的 WAF 会按客户端指纹白名单校验，只放行官方客户端。
--- 这里通过 build_headers 注入官方客户端 User-Agent 以通过校验。
--- 默认 QwenCode 指纹（实测可通）；可在 source.meta.user_agent 覆盖成 Claude Code 指纹。
-
+-- AgentRouter 的阿里云 WAF 按三重维度校验：出口 IP（必须海外）、
+-- TLS 指纹（JS/Go HTTP 层与 curl 不同）、浏览器指纹 header 集。
+-- 纯 UA 已不够：WAF 拦 12 种 agent CLI UA 中的 10 种（全 405 HTML），
+-- 只有同时带 Origin: qwen.ai + Referer + X-Requested-With 才放行，
+-- 且同 IP 短时间连续 3+ 次请求会被速率封禁，靠 adapter 侧低频调用 +
+-- llmsproxy 的 prefFailStep 冷却自然限制，来源无法控制速率。
 local default_ua = "QwenCode/0.2.0 (linux; x64)"
 
 -- AgentRouter fronts Claude models (claude-opus-4-8), and Claude upstreams
@@ -65,6 +67,13 @@ function adapter.build_headers(meta)
         ["Content-Type"] = "application/json",
         ["Authorization"] = "Bearer " .. meta.api_key,
         ["User-Agent"] = ua,
+        -- QwenCode client fingerprint: WAF rejects bare UA without these.
+        ["Accept"] = "application/json, text/plain, */*",
+        ["Accept-Language"] = "zh-CN,zh;q=0.9",
+        ["Origin"] = "https://qwen.ai",
+        ["Referer"] = "https://qwen.ai/",
+        ["X-Requested-With"] = "XMLHttpRequest",
+        ["Connection"] = "keep-alive",
     }
 end