fix: cross-platform path handling in mock filesystem and download

Adds RemoteBase, RemoteDir, RemoteJoin helpers to fileutils for
handling implant paths (which may use Windows backslashes) on any
host OS. Replaces all filepath.Base/Dir/Join calls on remote paths
with these cross-platform helpers across download, explorer, mock
filesystem, and e2e tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: M09Ic

client/command/explorer/file.go

@@ -6,11 +6,11 @@ import (
 	"github.com/chainreactors/IoM-go/proto/client/clientpb"
 	"github.com/chainreactors/IoM-go/proto/implant/implantpb"
 	"github.com/chainreactors/malice-network/client/core"
+	"github.com/chainreactors/malice-network/helper/utils/fileutils"
 	"github.com/chainreactors/tui"
 	tea "github.com/charmbracelet/bubbletea"
 	"github.com/spf13/cobra"
-	"path/filepath"
-	"strconv"
+"strconv"
 	"strings"
 	"time"
 )
@@ -87,7 +87,7 @@ func fileExplorerCmd(cmd *cobra.Command, con *core.Console) {
 			return
 		}
 		fileModel = fileModel.SetHeaderView(func(m *tui.TreeModel) string {
-			return fmt.Sprintf("Current Path: %s%s\n", root.Name, filepath.Join(m.Selected...))
+			return fmt.Sprintf("Current Path: %s%s\n", root.Name, fileutils.RemoteJoin(m.Selected...))
 		})
 		// Register custom action for 'enter' key
 		fileModel = fileModel.SetKeyBinding("enter", func(m *tui.TreeModel) (tea.Model, tea.Cmd) {
@@ -150,10 +150,10 @@ func fileEnterFunc(cmd *cobra.Command, m *tui.TreeModel, con *core.Console) (tea
 	if selectedNode.Info[0] == "false" {
 		return m, nil
 	}
-	path := filepath.Join(m.Selected...)
+	path := fileutils.RemoteJoin(m.Selected...)
 	task, err := con.Rpc.Ls(session.Clone(consts.CalleeExplorer).Context(), &implantpb.Request{
 		Name:  consts.ModuleLs,
-		Input: filepath.Join(m.Root.Name, path, selectedNode.Name),
+		Input: fileutils.RemoteJoin(m.Root.Name, path, selectedNode.Name),
 	})
 	session.Console(task, string(*con.App.Shell().Line()))
 	if err != nil {

client/command/file/download.go

@@ -6,9 +6,8 @@ import (
 	"github.com/chainreactors/IoM-go/proto/implant/implantpb"
 	"github.com/chainreactors/IoM-go/proto/services/clientrpc"
 	"github.com/chainreactors/malice-network/client/core"
+	"github.com/chainreactors/malice-network/helper/utils/fileutils"
 	"github.com/spf13/cobra"
-	"path"
-	"strings"
 )
 
 func DownloadCmd(cmd *cobra.Command, con *core.Console) error {
@@ -24,16 +23,9 @@ func DownloadCmd(cmd *cobra.Command, con *core.Console) error {
 	return nil
 }
 
-// remotePath extracts the basename from a remote path that may use
-// either forward slashes (Unix) or backslashes (Windows).
-func remotePath(p string) string {
-	// Normalise Windows backslashes so path.Base works on all platforms.
-	return path.Base(strings.ReplaceAll(p, `\`, "/"))
-}
-
 func Download(rpc clientrpc.MaliceRPCClient, session *client.Session, path string, is_dir bool) (*clientpb.Task, error) {
 	task, err := rpc.Download(session.Context(), &implantpb.DownloadRequest{
-		Name: remotePath(path),
+		Name: fileutils.RemoteBase(path),
 		Path: path,
 		Dir:  is_dir,
 	})

helper/utils/fileutils/path.go

@@ -1,6 +1,7 @@
 package fileutils
 
 import (
+	"path"
 	"regexp"
 	"strings"
 )
@@ -81,6 +82,29 @@ func CheckLinuxPath(path string) bool {
 	}
 	return true
 }
+// toForwardSlash normalises a remote path (which may use Windows backslashes)
+// to forward slashes so that the standard path package works on any OS.
+func toForwardSlash(p string) string {
+	return strings.ReplaceAll(p, `\`, "/")
+}
+
+// RemoteBase extracts the last element of a remote path that may use either
+// forward or backward slashes, working correctly on any host OS.
+func RemoteBase(p string) string {
+	return path.Base(toForwardSlash(p))
+}
+
+// RemoteDir returns the parent directory of a remote path.
+func RemoteDir(p string) string {
+	return path.Dir(toForwardSlash(p))
+}
+
+// RemoteJoin joins remote path elements using forward slashes,
+// suitable for building implant-side paths that work across OSes.
+func RemoteJoin(elem ...string) string {
+	return path.Join(elem...)
+}
+
 func CheckFullPath(path string) bool {
 	checkWindowsPath := CheckWindowsPath(path)
 	checkLinuxPath := CheckLinuxPath(path)

server/mock_implant_common_rpc_e2e_test.go

@@ -5,7 +5,7 @@ package main
 import (
 	"context"
 	"os"
-	"path/filepath"
+	stdpath "path"
 	"strings"
 	"testing"
 	"time"
@@ -14,6 +14,7 @@ import (
 	"github.com/chainreactors/IoM-go/proto/client/clientpb"
 	implantpb "github.com/chainreactors/IoM-go/proto/implant/implantpb"
 	"github.com/chainreactors/IoM-go/proto/services/clientrpc"
+	"github.com/chainreactors/malice-network/helper/utils/fileutils"
 	"github.com/chainreactors/malice-network/helper/utils/output"
 	"github.com/chainreactors/malice-network/server/internal/core"
 	"github.com/chainreactors/malice-network/server/testsupport"
@@ -115,17 +116,19 @@ func requireAddon(t *testing.T, addons []*implantpb.Addon, want string) {
 	t.Fatalf("addon list does not contain %q", want)
 }
 
-func normalizePath(path string) string {
-	path = strings.TrimSpace(path)
-	if path == "" {
+func normalizePath(p string) string {
+	p = strings.TrimSpace(p)
+	if p == "" {
 		return ""
 	}
-	path = strings.ReplaceAll(path, "/", `\`)
-	path = filepath.Clean(path)
-	if len(path) == 2 && strings.HasSuffix(path, ":") {
-		path += `\`
+	// Normalise to forward slashes for path.Clean, then back to backslashes.
+	p = strings.ReplaceAll(p, `\`, "/")
+	p = stdpath.Clean(p)
+	p = strings.ReplaceAll(p, "/", `\`)
+	if len(p) == 2 && strings.HasSuffix(p, ":") {
+		p += `\`
 	}
-	return strings.ToLower(path)
+	return strings.ToLower(p)
 }
 
 func requireFileInfo(t *testing.T, files []*implantpb.FileInfo, want string) {
@@ -1022,7 +1025,7 @@ func TestMockImplantFilesystemMutationRPCsE2E(t *testing.T) {
 func TestMockImplantFileTransferRPCsE2E(t *testing.T) {
 	f := newMockRPCFixture(t)
 
-	uploadedPath := filepath.Join(f.lib.WorkDir, "uploaded.txt")
+	uploadedPath := fileutils.RemoteJoin(f.lib.WorkDir, "uploaded.txt")
 	uploadBody := []byte("uploaded from mock implant e2e")
 
 	uploadBefore := len(f.mock.RequestsByName(consts.ModuleUpload))
@@ -1083,7 +1086,7 @@ func TestMockImplantFileTransferRPCsE2E(t *testing.T) {
 	downloadBefore := len(f.mock.RequestsByName(consts.ModuleDownload))
 	downloadTask, err := f.rpc.Download(f.session, &implantpb.DownloadRequest{
 		Path: f.lib.NotesPath,
-		Name: filepath.Base(f.lib.NotesPath),
+		Name: fileutils.RemoteBase(f.lib.NotesPath),
 	})
 	if err != nil {
 		t.Fatalf("Download failed: %v", err)

server/testsupport/mock_scenarios.go

@@ -8,6 +8,8 @@ import (
 	"encoding/hex"
 	"fmt"
 	stdpath "path"
+
+	"github.com/chainreactors/malice-network/helper/utils/fileutils"
 	"sort"
 	"strings"
 	"sync"
@@ -1117,10 +1119,10 @@ func (s *MockScenarioLibrary) ensureDir(path string) {
 		return
 	}
 	s.dirEntries[path] = map[string]*implantpb.FileInfo{}
-	parent := s.normPath(winDir(path))
+	parent := s.normPath(fileutils.RemoteDir(path))
 	if parent != "" && parent != path {
 		s.ensureDir(parent)
-		name := winBase(path)
+		name := fileutils.RemoteBase(path)
 		s.dirEntries[parent][name] = &implantpb.FileInfo{
 			Name:    name,
 			IsDir:   true,
@@ -1133,9 +1135,9 @@ func (s *MockScenarioLibrary) ensureDir(path string) {
 
 func (s *MockScenarioLibrary) setFile(path string, data []byte) {
 	path = s.normPath(path)
-	parent := s.normPath(winDir(path))
+	parent := s.normPath(fileutils.RemoteDir(path))
 	s.ensureDir(parent)
-	name := winBase(path)
+	name := fileutils.RemoteBase(path)
 	s.dirEntries[parent][name] = &implantpb.FileInfo{
 		Name:    name,
 		IsDir:   false,
@@ -1148,8 +1150,8 @@ func (s *MockScenarioLibrary) setFile(path string, data []byte) {
 
 func (s *MockScenarioLibrary) removePath(path string) {
 	path = s.normPath(path)
-	parent := s.normPath(winDir(path))
-	name := winBase(path)
+	parent := s.normPath(fileutils.RemoteDir(path))
+	name := fileutils.RemoteBase(path)
 	delete(s.fileContents, path)
 	delete(s.dirEntries, path)
 	if entries, ok := s.dirEntries[parent]; ok {
@@ -1281,17 +1283,6 @@ func (s *MockScenarioLibrary) normPath(p string) string {
 	return strings.ToLower(p)
 }
 
-// winDir returns the parent directory of a Windows-style backslash path,
-// working correctly on any OS by normalising to forward slashes first.
-func winDir(p string) string {
-	return strings.ReplaceAll(stdpath.Dir(strings.ReplaceAll(p, `\`, "/")), "/", `\`)
-}
-
-// winBase returns the last element of a Windows-style backslash path.
-func winBase(p string) string {
-	return stdpath.Base(strings.ReplaceAll(p, `\`, "/"))
-}
-
 func (s *MockScenarioLibrary) execOutputLocked(request *implantpb.ExecRequest) ([]MockExecChunk, []byte) {
 	if request == nil {
 		return nil, nil