Clean paths when looking in Storage (#19124) * Clean paths when looking in Storage Ensure paths are clean for minio aswell as local storage. Use url.Path not RequestURI/EscapedPath in storageHandler. Signed-off-by: Andrew Thornton <art27@cantab.net> * Apply suggestions from code review Co-authored-by: Lauris BH <lauris@nix.lv>

Changes

4 changed files (+40/-51)

• modules/storage/local.go
  • @@ -6,7 +6,6 @@ package storage
    import ( "context" - "errors" "io" "net/url" "os"
  • @@ -18,8 +17,6 @@ import (
    "code.gitea.io/gitea/modules/util" ) - // ErrLocalPathNotSupported represents an error that path is not supported - var ErrLocalPathNotSupported = errors.New("local path is not supported") var _ ObjectStorage = &LocalStorage{} // LocalStorageType is the type descriptor for local storage
  • @@ -62,21 +59,18 @@ func NewLocalStorage(ctx context.Context, cfg interface{}) (ObjectStorage, error
    }, nil } + func (l *LocalStorage) buildLocalPath(p string) string { + return filepath.Join(l.dir, path.Clean("/" + strings.ReplaceAll(p, "\\", "/"))[1:]) + } + // Open a file func (l *LocalStorage) Open(path string) (Object, error) { - if !isLocalPathValid(path) { - return nil, ErrLocalPathNotSupported - } - return os.Open(filepath.Join(l.dir, path)) + return os.Open(l.buildLocalPath(path)) } // Save a file func (l *LocalStorage) Save(path string, r io.Reader, size int64) (int64, error) { - if !isLocalPathValid(path) { - return 0, ErrLocalPathNotSupported - } - - p := filepath.Join(l.dir, path) + p := l.buildLocalPath(path) if err := os.MkdirAll(filepath.Dir(p), os.ModePerm); err != nil { return 0, err }
  • @@ -116,24 +110,12 @@ func (l *LocalStorage) Save(path string, r io.Reader, size int64) (int64, error)
    // Stat returns the info of the file func (l *LocalStorage) Stat(path string) (os.FileInfo, error) { - return os.Stat(filepath.Join(l.dir, path)) - } - - func isLocalPathValid(p string) bool { - a := path.Clean(p) - if strings.HasPrefix(a, "../") || strings.HasPrefix(a, "..\\") { - return false - } - return a == p + return os.Stat(l.buildLocalPath(path)) } // Delete delete a file func (l *LocalStorage) Delete(path string) error { - if !isLocalPathValid(path) { - return ErrLocalPathNotSupported - } - p := filepath.Join(l.dir, path) - return util.Remove(p) + return util.Remove(l.buildLocalPath(path)) } // URL gets the redirect URL to a file
• modules/storage/local_test.go
  • @@ -10,36 +10,44 @@ import (
    "github.com/stretchr/testify/assert" ) - func TestLocalPathIsValid(t *testing.T) { + func TestBuildLocalPath(t *testing.T) { kases := []struct { - path string - valid bool + localDir string + path string + expected string }{ { + "a", + "0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", "a/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", - true, }, { - "../a/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", - false, + "a", + "../0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", + "a/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", }, { - "a\\0\\a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", - true, + "a", + "0\\a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", + "a/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", }, { - "b/../a/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", - false, + "b", + "a/../0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", + "b/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", }, { - "..\\a/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", - false, + "b", + "a\\..\\0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", + "b/0/a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a14", }, } for _, k := range kases { t.Run(k.path, func(t *testing.T) { - assert.EqualValues(t, k.valid, isLocalPathValid(k.path)) + l := LocalStorage{dir: k.localDir} + + assert.EqualValues(t, k.expected, l.buildLocalPath(k.path)) }) } }
• modules/storage/minio.go
  • @@ -117,7 +117,7 @@ func NewMinioStorage(ctx context.Context, cfg interface{}) (ObjectStorage, error
    } func (m *MinioStorage) buildMinioPath(p string) string { - return strings.TrimPrefix(path.Join(m.basePath, p), "/") + return strings.TrimPrefix(path.Join(m.basePath, path.Clean("/" + strings.ReplaceAll(p, "\\", "/"))[1:]), "/") } // Open open a file
• routers/web/base.go
  • @@ -11,7 +11,6 @@ import (
    "net/http" "os" "path" - "path/filepath" "strings" "code.gitea.io/gitea/modules/context"
  • @@ -28,6 +27,7 @@ import (
    ) func storageHandler(storageSetting setting.Storage, prefix string, objStore storage.ObjectStorage) func(next http.Handler) http.Handler { + prefix = strings.Trim(prefix, "/") funcInfo := routing.GetFuncInfo(storageHandler, prefix) return func(next http.Handler) http.Handler { if storageSetting.ServeDirect {
  • @@ -37,13 +37,15 @@ func storageHandler(storageSetting setting.Storage, prefix string, objStore stor
    return } - if !strings.HasPrefix(req.URL.RequestURI(), "/"+prefix) { + if !strings.HasPrefix(req.URL.Path, "/"+prefix+"/") { next.ServeHTTP(w, req) return } routing.UpdateFuncInfo(req.Context(), funcInfo) - rPath := strings.TrimPrefix(req.URL.RequestURI(), "/"+prefix) + rPath := strings.TrimPrefix(req.URL.Path, "/"+prefix+"/") + rPath = path.Clean("/" + strings.ReplaceAll(rPath, "\\", "/"))[1:] + u, err := objStore.URL(rPath, path.Base(rPath)) if err != nil { if os.IsNotExist(err) || errors.Is(err, os.ErrNotExist) {
  • @@ -55,11 +57,12 @@ func storageHandler(storageSetting setting.Storage, prefix string, objStore stor
    http.Error(w, fmt.Sprintf("Error whilst getting URL for %s %s", prefix, rPath), 500) return } + http.Redirect( w, req, u.String(), - 301, + http.StatusMovedPermanently, ) }) }
  • @@ -70,22 +73,18 @@ func storageHandler(storageSetting setting.Storage, prefix string, objStore stor
    return } - prefix := strings.Trim(prefix, "/") - - if !strings.HasPrefix(req.URL.EscapedPath(), "/"+prefix+"/") { + if !strings.HasPrefix(req.URL.Path, "/"+prefix+"/") { next.ServeHTTP(w, req) return } routing.UpdateFuncInfo(req.Context(), funcInfo) - rPath := strings.TrimPrefix(req.URL.EscapedPath(), "/"+prefix+"/") - rPath = strings.TrimPrefix(rPath, "/") + rPath := strings.TrimPrefix(req.URL.Path, "/"+prefix+"/") + rPath = path.Clean("/" + strings.ReplaceAll(rPath, "\\", "/"))[1:] if rPath == "" { http.Error(w, "file not found", 404) return } - rPath = path.Clean("/" + filepath.ToSlash(rPath)) - rPath = rPath[1:] fi, err := objStore.Stat(rPath) if err == nil && httpcache.HandleTimeCache(req, w, fi) {