diff options
Diffstat (limited to 'network/receivepack/service/quarantine.go')
| -rw-r--r-- | network/receivepack/service/quarantine.go | 274 |
1 files changed, 0 insertions, 274 deletions
diff --git a/network/receivepack/service/quarantine.go b/network/receivepack/service/quarantine.go deleted file mode 100644 index 0bd98aeb..00000000 --- a/network/receivepack/service/quarantine.go +++ /dev/null @@ -1,274 +0,0 @@ -package service - -import ( - "bytes" - "crypto/rand" - "errors" - "fmt" - "io" - "io/fs" - "os" - "path" - "slices" -) - -// createQuarantineRoot creates one per-push quarantine directory beneath the -// permanent objects root. -// -// It returns both the quarantine directory name relative to ObjectsRoot and an -// opened root for that directory. Callers use the name for later promotion or -// removal relative to ObjectsRoot, and use the opened root for capability-based -// access within the quarantine itself. -func (service *Service) createQuarantineRoot() (string, *os.Root, error) { - name := "tmp_objdir-incoming-" + rand.Text() - - err := service.opts.ObjectsRoot.Mkdir(name, 0o700) - if err != nil { - return "", nil, err - } - - root, err := service.opts.ObjectsRoot.OpenRoot(name) - if err != nil { - _ = service.opts.ObjectsRoot.RemoveAll(name) - - return "", nil, err - } - - return name, root, nil -} - -func (service *Service) openQuarantinePackRoot(quarantineRoot *os.Root) (*os.Root, error) { - err := quarantineRoot.Mkdir("pack", 0o755) - if err != nil && !os.IsExist(err) { - return nil, err - } - - return quarantineRoot.OpenRoot("pack") -} - -func (service *Service) promoteQuarantine(quarantineName string, quarantineRoot *os.Root) error { - if quarantineName == "" || quarantineRoot == nil { - return nil - } - - return service.promoteQuarantineDir(quarantineName, quarantineRoot, ".") -} - -func (service *Service) promoteQuarantineDir(quarantineName string, quarantineRoot *os.Root, rel string) error { - entries, err := fs.ReadDir(quarantineRoot.FS(), rel) - if err != nil && !os.IsNotExist(err) { - return err - } - - slices.SortFunc(entries, func(left, right fs.DirEntry) int { - return packCopyPriority(left.Name()) - packCopyPriority(right.Name()) - }) - - for _, entry := range entries { - childRel := entry.Name() - if rel != "." { - childRel = path.Join(rel, entry.Name()) - } - - if entry.IsDir() { - err = service.opts.ObjectsRoot.Mkdir(childRel, 0o755) - if err != nil && !os.IsExist(err) { - return err - } - - err = service.applyPromotedDirectoryPermissions(childRel) - if err != nil { - return err - } - - err = service.promoteQuarantineDir(quarantineName, quarantineRoot, childRel) - if err != nil { - return err - } - - continue - } - - err = finalizeQuarantineFile( - service.opts.ObjectsRoot, - path.Join(quarantineName, childRel), - childRel, - isLooseObjectShardPath(rel), - service.opts.PromotedObjectPermissions, - ) - if err == nil { - continue - } - - return err - } - - return nil -} - -func packCopyPriority(name string) int { - if !pathHasPackPrefix(name) { - return 0 - } - - switch { - case path.Ext(name) == ".keep": - return 1 - case path.Ext(name) == ".pack": - return 2 - case path.Ext(name) == ".rev": - return 3 - case path.Ext(name) == ".idx": - return 4 - default: - return 5 - } -} - -func pathHasPackPrefix(name string) bool { - return len(name) >= 4 && name[:4] == "pack" -} - -func isLooseObjectShardPath(rel string) bool { - return len(rel) == 2 && isHex(rel[0]) && isHex(rel[1]) -} - -func isHex(ch byte) bool { - return ('0' <= ch && ch <= '9') || ('a' <= ch && ch <= 'f') || ('A' <= ch && ch <= 'F') -} - -func (service *Service) applyPromotedDirectoryPermissions(name string) error { - if service.opts.PromotedObjectPermissions == nil { - return nil - } - - return service.opts.ObjectsRoot.Chmod(name, service.opts.PromotedObjectPermissions.DirMode) -} - -func applyPromotedFilePermissions( - root *os.Root, - name string, - perms *PromotedObjectPermissions, -) error { - if perms == nil { - return nil - } - - return root.Chmod(name, perms.FileMode) -} - -func finalizeQuarantineFile( - root *os.Root, - src, dst string, - skipCollisionCheck bool, - perms *PromotedObjectPermissions, -) error { - const maxVanishedRetries = 5 - - for retries := 0; ; retries++ { - err := root.Link(src, dst) - switch { - case err == nil: - _ = root.Remove(src) - - return applyPromotedFilePermissions(root, dst, perms) - case !errors.Is(err, fs.ErrExist): - _, statErr := root.Stat(dst) - switch { - case statErr == nil: - err = fs.ErrExist - case errors.Is(statErr, fs.ErrNotExist): - renameErr := root.Rename(src, dst) - if renameErr == nil { - return applyPromotedFilePermissions(root, dst, perms) - } - - err = renameErr - default: - _ = root.Remove(src) - - return statErr - } - } - - if !errors.Is(err, fs.ErrExist) { - _ = root.Remove(src) - - return fmt.Errorf("promote quarantine %q -> %q: %w", src, dst, err) - } - - if skipCollisionCheck { - _ = root.Remove(src) - - return applyPromotedFilePermissions(root, dst, perms) - } - - equal, vanished, cmpErr := compareRootFiles(root, src, dst) - if vanished { - if retries >= maxVanishedRetries { - return fmt.Errorf("promote quarantine %q -> %q: destination repeatedly vanished", src, dst) - } - - continue - } - - if cmpErr != nil { - return cmpErr - } - - if !equal { - return fmt.Errorf("promote quarantine %q -> %q: files differ in contents", src, dst) - } - - _ = root.Remove(src) - - return applyPromotedFilePermissions(root, dst, perms) - } -} - -func compareRootFiles(root *os.Root, left, right string) (equal bool, vanished bool, err error) { - leftFile, err := root.Open(left) - if err != nil { - return false, false, err - } - - defer func() { - _ = leftFile.Close() - }() - - rightFile, err := root.Open(right) - if err != nil { - if errors.Is(err, fs.ErrNotExist) { - return false, true, nil - } - - return false, false, err - } - - defer func() { - _ = rightFile.Close() - }() - - var leftBuf, rightBuf [4096]byte - - for { - leftN, leftErr := leftFile.Read(leftBuf[:]) - rightN, rightErr := rightFile.Read(rightBuf[:]) - - if leftErr != nil && !errors.Is(leftErr, io.EOF) { - return false, false, leftErr - } - - if rightErr != nil && !errors.Is(rightErr, io.EOF) { - return false, false, rightErr - } - - if leftN != rightN || !bytes.Equal(leftBuf[:leftN], rightBuf[:rightN]) { - return false, false, nil - } - - if leftErr != nil || rightErr != nil { - return true, false, nil - } - } -} |