fix: 修复 read 工具路径解析问题

- 添加 home 目录路径 (~) 展开支持
- 添加外部路径权限检查和审批流程
- 改进路径解析逻辑，支持绝对路径和相对路径

Made-with: Cursor

Author: YingchaoX

internal/bootstrap/build_helpers.go

@@ -70,7 +70,7 @@ func buildToolRegistry(
 	todoWriteTool := tools.NewTodoWriteTool(store, func() string { return *sessionIDRef })
 
 	toolList := []tools.Tool{
-		tools.NewReadTool(ws),
+		tools.NewReadTool(ws, policy),
 		tools.NewWriteTool(ws),
 		tools.NewEditTool(ws),
 		tools.NewListTool(ws),

internal/config/config.go

@@ -242,7 +242,7 @@ func Default() Config {
 				"pnpm test*": "allow",
 				"yarn test*": "allow",
 			},
-			ExternalDir: "deny",
+			ExternalDir: "ask",
 		},
 		Workflow: WorkflowConfig{
 			RequireTodoForComplex: true,

internal/permission/policy.go

@@ -254,13 +254,15 @@ func PresetConfig(name string) (config.PermissionConfig, bool) {
 			Default: "ask", Read: "allow", Edit: "ask", Write: "ask", List: "allow", Glob: "allow", Grep: "allow", Patch: "ask",
 			LSPDiagnostics: "allow", LSPDefinition: "allow", LSPHover: "allow",
 			TodoRead: "allow", TodoWrite: "allow", Skill: "ask", Task: "ask", Fetch: "ask",
+			ExternalDir: "ask",
 			Bash: map[string]string{"*": "ask", "ls *": "allow", "cat *": "allow", "grep *": "allow", "go test *": "allow", "pytest*": "allow", "npm test*": "allow", "pnpm test*": "allow", "yarn test*": "allow"},
 		}, true
 	case "plan":
 		return config.PermissionConfig{
 			Default: "ask", Read: "allow", Edit: "deny", Write: "deny", List: "allow", Glob: "allow", Grep: "allow", Patch: "deny",
 			LSPDiagnostics: "allow", LSPDefinition: "allow", LSPHover: "allow",
 			TodoRead: "allow", TodoWrite: "allow", Skill: "allow", Task: "deny", Fetch: "allow", Question: "allow",
+			ExternalDir: "ask",
 			Bash: map[string]string{
 				"*":            "ask",
 				"ls":           "allow",
@@ -296,3 +298,8 @@ func (p *Policy) ApplyPreset(name string) bool {
 	p.cfg = cfg
 	return true
 }
+
+// ExternalDirDecision 返回外部目录访问权限决策
+func (p *Policy) ExternalDirDecision() Decision {
+	return normalizeDecision(p.cfg.ExternalDir, DecisionAsk)
+}

internal/tools/read.go

@@ -6,24 +6,81 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
+	"path/filepath"
 	"strings"
 
 	"coder/internal/chat"
+	"coder/internal/permission"
 	"coder/internal/security"
 )
 
 type ReadTool struct {
-	ws *security.Workspace
+	ws     *security.Workspace
+	policy *permission.Policy
 }
 
-func NewReadTool(ws *security.Workspace) *ReadTool {
-	return &ReadTool{ws: ws}
+func NewReadTool(ws *security.Workspace, policy *permission.Policy) *ReadTool {
+	return &ReadTool{ws: ws, policy: policy}
 }
 
 func (t *ReadTool) Name() string {
 	return "read"
 }
 
+// ApprovalRequest 实现 ApprovalAware 接口，检查是否需要审批外部路径
+// ApprovalRequest implements ApprovalAware interface to check if external path needs approval
+func (t *ReadTool) ApprovalRequest(args json.RawMessage) (*ApprovalRequest, error) {
+	var in struct {
+		Path string `json:"path"`
+	}
+	if err := json.Unmarshal(args, &in); err != nil {
+		return nil, fmt.Errorf("parse args: %w", err)
+	}
+
+	path := strings.TrimSpace(in.Path)
+	if path == "" {
+		return nil, nil
+	}
+
+	// 解析路径（展开 ~）
+	if strings.HasPrefix(path, "~") {
+		expanded, err := t.expandHomePath(path)
+		if err != nil {
+			return nil, nil // 解析失败，让 Execute 处理错误
+		}
+		path = expanded
+	}
+
+	// 如果不是绝对路径，不需要审批（相对路径限制在 workspace 内）
+	if !filepath.IsAbs(path) {
+		return nil, nil
+	}
+
+	// 检查是否在 workspace 内
+	rel, err := filepath.Rel(t.ws.Root(), path)
+	if err == nil && rel != ".." && !strings.HasPrefix(rel, ".."+string(os.PathSeparator)) {
+		// 在 workspace 内，不需要审批
+		return nil, nil
+	}
+
+	// 在 workspace 外，检查权限策略
+	decision := t.policy.ExternalDirDecision()
+	switch decision {
+	case permission.DecisionAllow:
+		// 允许，不需要审批
+		return nil, nil
+	case permission.DecisionDeny:
+		// 拒绝，不需要审批（直接拒绝）
+		return nil, nil
+	default:
+		// ask，需要审批
+		return &ApprovalRequest{
+			Tool:   t.Name(),
+			Reason: fmt.Sprintf("read external path: %s", in.Path),
+		}, nil
+	}
+}
+
 func (t *ReadTool) Definition() chat.ToolDef {
 	return chat.ToolDef{
 		Type: "function",
@@ -75,9 +132,9 @@ func (t *ReadTool) Execute(_ context.Context, args json.RawMessage) (string, err
 	if in.Limit > maxLimit {
 		in.Limit = maxLimit
 	}
-	resolved, err := t.ws.Resolve(in.Path)
-	if err != nil {
-		return "", fmt.Errorf("resolve path: %w", err)
+	resolved, resolveErr := t.resolvePath(in.Path)
+	if resolveErr != nil {
+		return "", fmt.Errorf("resolve path: %w", resolveErr)
 	}
 	f, err := os.Open(resolved)
 	if err != nil {
@@ -153,3 +210,78 @@ func (t *ReadTool) Execute(_ context.Context, args json.RawMessage) (string, err
 		"has_more":   hasMore,
 	}), nil
 }
+
+// resolvePath 统一处理路径解析，支持相对路径、绝对路径和 ~ 路径
+// resolvePath handles path resolution for relative, absolute and ~ paths
+func (t *ReadTool) resolvePath(path string) (string, error) {
+	path = strings.TrimSpace(path)
+	if path == "" {
+		return "", fmt.Errorf("empty path")
+	}
+
+	// 1. 处理 ~ 路径：展开为家目录绝对路径
+	// Handle ~ path: expand to home directory
+	if strings.HasPrefix(path, "~") {
+		expanded, err := t.expandHomePath(path)
+		if err != nil {
+			return "", err
+		}
+		path = expanded
+	}
+
+	// 2. 如果是绝对路径，检查外部权限
+	// If absolute path, check external permission
+	if filepath.IsAbs(path) {
+		return t.checkExternalPath(path)
+	}
+
+	// 3. 相对路径：限制在 workspace 内
+	// Relative path: restrict to workspace
+	return t.ws.Resolve(path)
+}
+
+// expandHomePath 将 ~ 展开为家目录绝对路径
+// expandHomePath expands ~ to home directory absolute path
+func (t *ReadTool) expandHomePath(path string) (string, error) {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return "", fmt.Errorf("resolve home dir: %w", err)
+	}
+
+	if path == "~" {
+		return home, nil
+	}
+	if strings.HasPrefix(path, "~/") {
+		return filepath.Join(home, strings.TrimPrefix(path, "~/")), nil
+	}
+	// ~username 格式暂不支持 / ~username format not supported
+	return "", fmt.Errorf("unsupported path format: %s", path)
+}
+
+// checkExternalPath 检查外部路径权限
+// checkExternalPath checks external path permission
+// 注意：当策略为 ask 时，如果 Execute 被调用，说明审批已通过
+// Note: when policy is ask, if Execute is called, approval has been granted
+func (t *ReadTool) checkExternalPath(absPath string) (string, error) {
+	// 检查路径是否在 workspace 内 / Check if path is inside workspace
+	rel, err := filepath.Rel(t.ws.Root(), absPath)
+	if err == nil && rel != ".." && !strings.HasPrefix(rel, ".."+string(os.PathSeparator)) {
+		// 路径在 workspace 内，直接允许 / Path inside workspace, allow directly
+		return absPath, nil
+	}
+
+	// 路径在 workspace 外，检查外部路径权限 / Path outside workspace, check permission
+	decision := t.policy.ExternalDirDecision()
+	switch decision {
+	case permission.DecisionAllow:
+		// 明确允许 / Explicitly allowed
+		return absPath, nil
+	case permission.DecisionDeny:
+		// 明确拒绝 / Explicitly denied
+		return "", fmt.Errorf("external path access denied by policy")
+	default:
+		// ask 策略：如果 Execute 被调用，说明审批已通过
+		// ask policy: if Execute is called, approval has been granted
+		return absPath, nil
+	}
+}

internal/tools/read_test.go

@@ -9,6 +9,8 @@ import (
 	"strings"
 	"testing"
 
+	"coder/internal/config"
+	"coder/internal/permission"
 	"coder/internal/security"
 )
 
@@ -28,7 +30,9 @@ func TestReadToolSmallFileDefaultLimit(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	tool := NewReadTool(ws)
+	cfg, _ := permission.PresetConfig("build")
+	policy := permission.New(cfg)
+	tool := NewReadTool(ws, policy)
 
 	// 仅传 path，不带 offset/limit，期望读出全部 10 行
 	args, _ := json.Marshal(map[string]any{
@@ -77,7 +81,9 @@ func TestReadToolLargeFilePagination(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	tool := NewReadTool(ws)
+	cfg, _ := permission.PresetConfig("build")
+	policy := permission.New(cfg)
+	tool := NewReadTool(ws, policy)
 
 	// 默认只读前 50 行
 	args, _ := json.Marshal(map[string]any{
@@ -126,7 +132,9 @@ func TestReadToolOffsetAndLimit(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	tool := NewReadTool(ws)
+	cfg, _ := permission.PresetConfig("build")
+	policy := permission.New(cfg)
+	tool := NewReadTool(ws, policy)
 
 	// 从第 51 行开始读 50 行
 	args, _ := json.Marshal(map[string]any{
@@ -172,7 +180,9 @@ func TestReadToolOffsetBeyondEOFAndInvalidLimit(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	tool := NewReadTool(ws)
+	cfg, _ := permission.PresetConfig("build")
+	policy := permission.New(cfg)
+	tool := NewReadTool(ws, policy)
 
 	// offset 大于文件总行数，期望 content 为空、has_more=false
 	argsBeyond, _ := json.Marshal(map[string]any{
@@ -204,3 +214,125 @@ func TestReadToolOffsetBeyondEOFAndInvalidLimit(t *testing.T) {
 		t.Fatalf("execute read (invalid limit): %v", err)
 	}
 }
+
+// TestReadToolExternalPathApproval 测试外部路径审批流程
+func TestReadToolExternalPathApproval(t *testing.T) {
+	// 创建一个临时目录作为 workspace
+	wsRoot := t.TempDir()
+	ws, err := security.NewWorkspace(wsRoot)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// 在工作区外创建一个文件
+	externalDir := t.TempDir()
+	externalFile := filepath.Join(externalDir, "external.txt")
+	externalContent := "external file content"
+	if err := os.WriteFile(externalFile, []byte(externalContent), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	// 测试策略为 ask 时，ApprovalRequest 应该返回需要审批
+	t.Run("ask_policy_returns_approval_request", func(t *testing.T) {
+		cfg := config.PermissionConfig{ExternalDir: "ask"}
+		policy := permission.New(cfg)
+		tool := NewReadTool(ws, policy)
+
+		args, _ := json.Marshal(map[string]any{
+			"path": externalFile,
+		})
+
+		req, err := tool.ApprovalRequest(args)
+		if err != nil {
+			t.Fatalf("ApprovalRequest error: %v", err)
+		}
+		if req == nil {
+			t.Fatal("expected ApprovalRequest for external path, got nil")
+		}
+		if req.Tool != "read" {
+			t.Fatalf("expected tool name 'read', got %q", req.Tool)
+		}
+	})
+
+	// 测试策略为 allow 时，ApprovalRequest 应该返回 nil
+	t.Run("allow_policy_no_approval_request", func(t *testing.T) {
+		cfg := config.PermissionConfig{ExternalDir: "allow"}
+		policy := permission.New(cfg)
+		tool := NewReadTool(ws, policy)
+
+		args, _ := json.Marshal(map[string]any{
+			"path": externalFile,
+		})
+
+		req, err := tool.ApprovalRequest(args)
+		if err != nil {
+			t.Fatalf("ApprovalRequest error: %v", err)
+		}
+		if req != nil {
+			t.Fatalf("expected no ApprovalRequest for allow policy, got %v", req)
+		}
+	})
+
+	// 测试策略为 deny 时，ApprovalRequest 应该返回 nil（直接拒绝）
+	t.Run("deny_policy_no_approval_request", func(t *testing.T) {
+		cfg := config.PermissionConfig{ExternalDir: "deny"}
+		policy := permission.New(cfg)
+		tool := NewReadTool(ws, policy)
+
+		args, _ := json.Marshal(map[string]any{
+			"path": externalFile,
+		})
+
+		req, err := tool.ApprovalRequest(args)
+		if err != nil {
+			t.Fatalf("ApprovalRequest error: %v", err)
+		}
+		if req != nil {
+			t.Fatalf("expected no ApprovalRequest for deny policy, got %v", req)
+		}
+	})
+
+	// 测试 ~ 路径展开和审批
+	t.Run("home_path_expansion_and_approval", func(t *testing.T) {
+		cfg := config.PermissionConfig{ExternalDir: "ask"}
+		policy := permission.New(cfg)
+		tool := NewReadTool(ws, policy)
+
+		args, _ := json.Marshal(map[string]any{
+			"path": "~/test_file.txt",
+		})
+
+		req, err := tool.ApprovalRequest(args)
+		if err != nil {
+			t.Fatalf("ApprovalRequest error: %v", err)
+		}
+		if req == nil {
+			t.Fatal("expected ApprovalRequest for ~ path, got nil")
+		}
+	})
+
+	// 测试工作区内路径不需要审批
+	t.Run("workspace_path_no_approval", func(t *testing.T) {
+		cfg := config.PermissionConfig{ExternalDir: "ask"}
+		policy := permission.New(cfg)
+		tool := NewReadTool(ws, policy)
+
+		// 在工作区内创建文件
+		internalFile := filepath.Join(wsRoot, "internal.txt")
+		if err := os.WriteFile(internalFile, []byte("internal content"), 0o644); err != nil {
+			t.Fatal(err)
+		}
+
+		args, _ := json.Marshal(map[string]any{
+			"path": "internal.txt",
+		})
+
+		req, err := tool.ApprovalRequest(args)
+		if err != nil {
+			t.Fatalf("ApprovalRequest error: %v", err)
+		}
+		if req != nil {
+			t.Fatalf("expected no ApprovalRequest for workspace path, got %v", req)
+		}
+	})
+}