package main import ( "bytes" "fmt" "os" "path/filepath" "sort" "strings" "sync" "syscall" "github.com/hanwen/go-fuse/fuse" "github.com/hanwen/go-fuse/fuse/nodefs" "github.com/rfjakob/gocryptfs/internal/exitcodes" "github.com/rfjakob/gocryptfs/internal/fusefrontend" "github.com/rfjakob/gocryptfs/internal/tlog" ) type fsckObj struct { fs *fusefrontend.FS // List of corrupt files corruptList []string // Protects corruptList corruptListLock sync.Mutex // stop a running watchMitigatedCorruptions thread watchDone chan struct{} // Inode numbers of hard-linked files (Nlink > 1) that we have already checked seenInodes map[uint64]struct{} } func (ck *fsckObj) markCorrupt(path string) { ck.corruptListLock.Lock() ck.corruptList = append(ck.corruptList, path) ck.corruptListLock.Unlock() } // Watch for mitigated corruptions that occour during OpenDir() func (ck *fsckObj) watchMitigatedCorruptionsOpenDir(path string) { for { select { case item := <-ck.fs.MitigatedCorruptions: fmt.Printf("fsck: corrupt entry in dir %q: %q\n", path, item) ck.markCorrupt(filepath.Join(path, item)) case <-ck.watchDone: return } } } // Recursively check dir for corruption func (ck *fsckObj) dir(path string) { tlog.Debug.Printf("ck.dir %q\n", path) ck.xattrs(path) // Run OpenDir and catch transparently mitigated corruptions go ck.watchMitigatedCorruptionsOpenDir(path) entries, status := ck.fs.OpenDir(path, nil) ck.watchDone <- struct{}{} // Also catch non-mitigated corruptions if !status.Ok() { ck.markCorrupt(path) fmt.Printf("fsck: error opening dir %q: %v\n", path, status) return } // Sort alphabetically sort.Sort(sortableDirEntries(entries)) for _, entry := range entries { if entry.Name == "." || entry.Name == ".." { continue } nextPath := filepath.Join(path, entry.Name) filetype := entry.Mode & syscall.S_IFMT //fmt.Printf(" %q %x\n", entry.Name, entry.Mode) switch filetype { case syscall.S_IFDIR: ck.dir(nextPath) case syscall.S_IFREG: ck.file(nextPath) case syscall.S_IFLNK: ck.symlink(nextPath) case syscall.S_IFIFO, syscall.S_IFSOCK, syscall.S_IFBLK, syscall.S_IFCHR: // nothing to check default: fmt.Printf("fsck: unhandled file type %x\n", filetype) } } } func (ck *fsckObj) symlink(path string) { _, status := ck.fs.Readlink(path, nil) if !status.Ok() { ck.markCorrupt(path) fmt.Printf("fsck: error reading symlink %q: %v\n", path, status) } } // Watch for mitigated corruptions that occour during Read() func (ck *fsckObj) watchMitigatedCorruptionsRead(path string) { for { select { case item := <-ck.fs.MitigatedCorruptions: fmt.Printf("fsck: corrupt file %q (inode %s)\n", path, item) ck.markCorrupt(path) case <-ck.watchDone: return } } } // Check file for corruption func (ck *fsckObj) file(path string) { tlog.Debug.Printf("ck.file %q\n", path) attr, status := ck.fs.GetAttr(path, nil) if !status.Ok() { ck.markCorrupt(path) fmt.Printf("fsck: error stating file %q: %v\n", path, status) return } if attr.Nlink > 1 { // Due to hard links, we may have already checked this file. if _, ok := ck.seenInodes[attr.Ino]; ok { tlog.Debug.Printf("ck.file : skipping %q (inode number %d already seen)\n", path, attr.Ino) return } ck.seenInodes[attr.Ino] = struct{}{} } ck.xattrs(path) f, status := ck.fs.Open(path, syscall.O_RDONLY, nil) if !status.Ok() { ck.markCorrupt(path) fmt.Printf("fsck: error opening file %q: %v\n", path, status) return } defer f.Release() allZero := make([]byte, fuse.MAX_KERNEL_WRITE) buf := make([]byte, fuse.MAX_KERNEL_WRITE) var off int64 // Read() through the whole file and catch transparently mitigated corruptions go ck.watchMitigatedCorruptionsRead(path) defer func() { ck.watchDone <- struct{}{} }() for { tlog.Debug.Printf("ck.file: read %d bytes from offset %d\n", len(buf), off) result, status := f.Read(buf, off) if !status.Ok() { ck.markCorrupt(path) fmt.Printf("fsck: error reading file %q (inum %d): %v\n", path, inum(f), status) return } // EOF if result.Size() == 0 { return } off += int64(result.Size()) // If we seem to be in the middle of a file hole, try to skip to the next // data section. if bytes.Equal(buf, allZero) { tlog.Debug.Printf("ck.file: trying to skip file hole\n") f2 := f.(*fusefrontend.File) nextOff, err := f2.SeekData(off) if err == nil { off = nextOff } } } } // Watch for mitigated corruptions that occour during ListXAttr() func (ck *fsckObj) watchMitigatedCorruptionsListXAttr(path string) { for { select { case item := <-ck.fs.MitigatedCorruptions: fmt.Printf("fsck: corrupt xattr name on file %q: %q\n", path, item) ck.markCorrupt(path + " xattr:" + item) case <-ck.watchDone: return } } } // Check xattrs on file/dir at path func (ck *fsckObj) xattrs(path string) { // Run ListXAttr() and catch transparently mitigated corruptions go ck.watchMitigatedCorruptionsListXAttr(path) attrs, status := ck.fs.ListXAttr(path, nil) ck.watchDone <- struct{}{} // Also catch non-mitigated corruptions if !status.Ok() { fmt.Printf("fsck: error listing xattrs on %q: %v\n", path, status) ck.markCorrupt(path) return } for _, a := range attrs { _, status := ck.fs.GetXAttr(path, a, nil) if !status.Ok() { fmt.Printf("fsck: error reading xattr %q from %q: %v\n", a, path, status) ck.markCorrupt(path) } } } func fsck(args *argContainer) { if args.reverse { tlog.Fatal.Printf("Running -fsck with -reverse is not supported") os.Exit(exitcodes.Usage) } args.allow_other = false pfs, wipeKeys := initFuseFrontend(args) fs := pfs.(*fusefrontend.FS) fs.MitigatedCorruptions = make(chan string) ck := fsckObj{ fs: fs, watchDone: make(chan struct{}), seenInodes: make(map[uint64]struct{}), } ck.dir("") wipeKeys() if len(ck.corruptList) == 0 { tlog.Info.Printf("fsck summary: no problems found\n") return } fmt.Printf("fsck summary: %d corrupt files\n", len(ck.corruptList)) os.Exit(exitcodes.FsckErrors) } type sortableDirEntries []fuse.DirEntry func (s sortableDirEntries) Len() int { return len(s) } func (s sortableDirEntries) Swap(i, j int) { s[i], s[j] = s[j], s[i] } func (s sortableDirEntries) Less(i, j int) bool { return strings.Compare(s[i].Name, s[j].Name) < 0 } func inum(f nodefs.File) uint64 { var a fuse.Attr f.GetAttr(&a) return a.Ino }