From 87d5afa703c6ad6bec5a24151c60885892964f0e Mon Sep 17 00:00:00 2001
From: wangjia <809946525@qq.com>
Date: Thu, 23 Jul 2026 02:01:45 +0800
Subject: [PATCH] =?UTF-8?q?feat(agent):=20=E6=B8=B2=E6=9F=93=E6=97=B6?=
 =?UTF-8?q?=E8=AF=BB=E5=8F=96=20ACL,=E5=86=85=E5=AD=98+=E7=A3=81=E7=9B=98?=
 =?UTF-8?q?=20last-good=20=E4=BF=9D=E8=AF=81=20fail-closed=20=E8=B7=A8?=
 =?UTF-8?q?=E9=87=8D=E5=90=AF?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 server/internal/agentd/acl.go      |  9 ++++
 server/internal/agentd/acl_test.go | 79 ++++++++++++++++++++++++++++++
 server/internal/agentd/singbox.go  | 53 +++++++++++++++++++-
 3 files changed, 140 insertions(+), 1 deletion(-)

diff --git a/server/internal/agentd/acl.go b/server/internal/agentd/acl.go
index 354b0e0..d9af0d7 100644
--- a/server/internal/agentd/acl.go
+++ b/server/internal/agentd/acl.go
@@ -176,3 +176,12 @@ func (ac *ACLConfig) rules() []any {
 	}
 	return out
 }
+
+// persistACL 把成功加载的 ACL 快照原子写到 path,供 agent 冷启动兜底。
+func persistACL(path string, ac *ACLConfig) error {
+	data, err := json.MarshalIndent(ac, "", "  ")
+	if err != nil {
+		return fmt.Errorf("agentd: marshal acl snapshot: %w", err)
+	}
+	return atomicWrite(path, data, 0o600)
+}
diff --git a/server/internal/agentd/acl_test.go b/server/internal/agentd/acl_test.go
index b849044..390f53e 100644
--- a/server/internal/agentd/acl_test.go
+++ b/server/internal/agentd/acl_test.go
@@ -1,10 +1,14 @@
 package agentd
 
 import (
+	"encoding/json"
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
+
+	agentv1 "github.com/wangjia/pangolin/server/internal/pb/agentv1"
 )
 
 // writeACL 把 acl.json 写到指定路径。
@@ -337,3 +341,78 @@ func TestBuildRoute_Matrix(t *testing.T) {
 		}
 	})
 }
+
+// 成功加载后必须把快照落盘,否则 agent 一重启 fail-closed 就失效。
+func TestACL_PersistsLastGoodOnLoad(t *testing.T) {
+	cfg := testConfig(t)
+	writeACL(t, cfg.ACLConfigPath, validACL)
+	sb := NewSingBox(cfg, nil)
+	sb.ApplyConfig(sampleSnapshot(&agentv1.Credential{DpUUID: "aaaa", Protocol: agentv1.ProtocolBoth}), true)
+
+	if _, err := sb.RenderConfig(); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := os.Stat(cfg.ACLLastGoodPath()); err != nil {
+		t.Fatalf("last-good 未落盘: %v", err)
+	}
+}
+
+// acl.json 被改坏 → 规则不能消失(内存 last-good 兜底)。
+func TestACL_BrokenFileKeepsInMemoryLastGood(t *testing.T) {
+	cfg := testConfig(t)
+	writeACL(t, cfg.ACLConfigPath, validACL)
+	sb := NewSingBox(cfg, nil)
+	sb.ApplyConfig(sampleSnapshot(&agentv1.Credential{DpUUID: "aaaa", Protocol: agentv1.ProtocolBoth}), true)
+	if _, err := sb.RenderConfig(); err != nil {
+		t.Fatal(err)
+	}
+
+	writeACL(t, cfg.ACLConfigPath, `{"enabled": true,`) // 手抖写坏
+	data, err := sb.RenderConfig()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(string(data), "reject") {
+		t.Fatal("acl.json 坏掉后拒绝规则消失了 —— 这是 fail-open,私有服务已敞开")
+	}
+}
+
+// 新 agent 实例(模拟进程重启)+ 坏 acl.json → 磁盘 last-good 兜底,规则仍在。
+func TestACL_ColdStartFallsBackToDiskLastGood(t *testing.T) {
+	cfg := testConfig(t)
+	writeACL(t, cfg.ACLConfigPath, validACL)
+	sb1 := NewSingBox(cfg, nil)
+	sb1.ApplyConfig(sampleSnapshot(&agentv1.Credential{DpUUID: "aaaa", Protocol: agentv1.ProtocolBoth}), true)
+	if _, err := sb1.RenderConfig(); err != nil {
+		t.Fatal(err)
+	}
+
+	writeACL(t, cfg.ACLConfigPath, `not json at all`)
+	sb2 := NewSingBox(cfg, nil) // 全新实例,内存 last-good 为空
+	sb2.ApplyConfig(sampleSnapshot(&agentv1.Credential{DpUUID: "aaaa", Protocol: agentv1.ProtocolBoth}), true)
+	data, err := sb2.RenderConfig()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(string(data), "reject") {
+		t.Fatal("冷启动未回退到磁盘 last-good,私有服务已敞开")
+	}
+}
+
+// 从未配置过(无 acl.json 也无 last-good)→ 不产出 route,且不误报。
+func TestACL_NeverConfiguredYieldsNoRoute(t *testing.T) {
+	cfg := testConfig(t)
+	sb := NewSingBox(cfg, nil)
+	sb.ApplyConfig(sampleSnapshot(&agentv1.Credential{DpUUID: "aaaa", Protocol: agentv1.ProtocolBoth}), true)
+	data, err := sb.RenderConfig()
+	if err != nil {
+		t.Fatal(err)
+	}
+	var m map[string]any
+	if err := json.Unmarshal(data, &m); err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := m["route"]; ok {
+		t.Error("未配置 ACL 也未启用 WARP,不应产出 route 块")
+	}
+}
diff --git a/server/internal/agentd/singbox.go b/server/internal/agentd/singbox.go
index e2c5b67..dc734ad 100644
--- a/server/internal/agentd/singbox.go
+++ b/server/internal/agentd/singbox.go
@@ -61,6 +61,10 @@ type SingBox struct {
 	hy2           *agentv1.Hy2Inbound
 	configVersion int64
 
+	// lastGoodACL 是最近一次成功加载的私有目的地 ACL。acl.json 读坏时回退到它,
+	// 而不是像 WARP 那样降级为「不启用」—— 对访问控制,降级即敞开。
+	lastGoodACL *ACLConfig
+
 	// started 标记 sing-box 是否已被本 agent 冷启动过:首次走 Restart(冷启动),
 	// 之后配置变更走 Reload(SIGHUP 热重载)。agent 进程重启后复位为 false,
 	// 下次渲染做一次冷启动以确保与渲染配置一致。
@@ -323,7 +327,54 @@ func (s *SingBox) RenderConfig() ([]byte, error) {
 		logf("[warp] load %s failed, WARP routing disabled: %v", s.cfg.WarpConfigPath, err)
 		warp = nil
 	}
-	return renderSingboxConfig(creds, reality, hy2, s.cfg.DeriveKey, warp, nil)
+	return renderSingboxConfig(creds, reality, hy2, s.cfg.DeriveKey, warp, s.loadACL())
+}
+
+// loadACL 读取私有目的地 ACL,并维护 last-good 兜底。
+//
+// 语义刻意与 WARP 相反:WARP 读失败静默降级为「不分流」是安全的,ACL 读失败若也
+// 降级为「不启用」,等于把私有服务对全体 pangolin 用户敞开,而且是静默的。故:
+//   - 成功  → 更新内存 last-good 并落盘,供本进程后续与下次冷启动使用
+//   - 失败/文件消失 → 回退内存 last-good,再回退磁盘 last-good,规则不消失
+//   - 两级 last-good 都没有 → 只能不产出规则(白名单与目的地清单同在一个文件,
+//     文件全丢时连「该拒绝哪些目的地」都无从得知),此时必须大声告警
+func (s *SingBox) loadACL() *ACLConfig {
+	acl, err := LoadACLConfig(s.cfg.ACLConfigPath)
+	switch {
+	case err == nil && acl != nil:
+		s.mu.Lock()
+		s.lastGoodACL = acl
+		s.mu.Unlock()
+		if perr := persistACL(s.cfg.ACLLastGoodPath(), acl); perr != nil {
+			logf("[acl] persist last-good to %s failed: %v", s.cfg.ACLLastGoodPath(), perr)
+		}
+		return acl
+	case err != nil:
+		logf("[acl] ERROR load %s failed: %v", s.cfg.ACLConfigPath, err)
+	}
+
+	s.mu.Lock()
+	lg := s.lastGoodACL
+	s.mu.Unlock()
+	if lg != nil {
+		logf("[acl] falling back to in-memory last-good ACL")
+		return lg
+	}
+
+	disk, derr := LoadACLConfig(s.cfg.ACLLastGoodPath())
+	if derr == nil && disk != nil {
+		logf("[acl] falling back to on-disk last-good %s", s.cfg.ACLLastGoodPath())
+		s.mu.Lock()
+		s.lastGoodACL = disk
+		s.mu.Unlock()
+		return disk
+	}
+
+	if err != nil {
+		logf("[acl] ALERT acl.json is broken and no last-good snapshot exists — "+
+			"private destinations are UNPROTECTED (path=%s)", s.cfg.ACLConfigPath)
+	}
+	return nil
 }
 
 // writeAndRestart renders, writes the config file and restarts sing-box.