Exemplo n.º 1
0
func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader, Lchown bool) error {
	// hdr.Mode is in linux format, which we can use for sycalls,
	// but for os.Foo() calls we need the mode converted to os.FileMode,
	// so use hdrInfo.Mode() (they differ for e.g. setuid bits)
	hdrInfo := hdr.FileInfo()

	switch hdr.Typeflag {
	case tar.TypeDir:
		// Create directory unless it exists as a directory already.
		// In that case we just want to merge the two
		if fi, err := os.Lstat(path); !(err == nil && fi.IsDir()) {
			if err := os.Mkdir(path, hdrInfo.Mode()); err != nil {
				return err
			}
		}

	case tar.TypeReg, tar.TypeRegA:
		// Source is regular file
		file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, hdrInfo.Mode())
		if err != nil {
			return err
		}
		if _, err := io.Copy(file, reader); err != nil {
			file.Close()
			return err
		}
		file.Close()

	case tar.TypeBlock, tar.TypeChar, tar.TypeFifo:
		mode := uint32(hdr.Mode & 07777)
		switch hdr.Typeflag {
		case tar.TypeBlock:
			mode |= syscall.S_IFBLK
		case tar.TypeChar:
			mode |= syscall.S_IFCHR
		case tar.TypeFifo:
			mode |= syscall.S_IFIFO
		}

		if err := syscall.Mknod(path, mode, int(mkdev(hdr.Devmajor, hdr.Devminor))); err != nil {
			return err
		}

	case tar.TypeLink:
		if err := os.Link(filepath.Join(extractDir, hdr.Linkname), path); err != nil {
			return err
		}

	case tar.TypeSymlink:
		if err := os.Symlink(hdr.Linkname, path); err != nil {
			return err
		}

	case tar.TypeXGlobalHeader:
		log.Debugf("PAX Global Extended Headers found and ignored")
		return nil

	default:
		return fmt.Errorf("Unhandled tar header type %d\n", hdr.Typeflag)
	}

	if err := os.Lchown(path, hdr.Uid, hdr.Gid); err != nil && Lchown {
		return err
	}

	for key, value := range hdr.Xattrs {
		if err := system.Lsetxattr(path, key, []byte(value), 0); err != nil {
			return err
		}
	}

	// There is no LChmod, so ignore mode for symlink. Also, this
	// must happen after chown, as that can modify the file mode
	if hdr.Typeflag != tar.TypeSymlink {
		if err := os.Chmod(path, hdrInfo.Mode()); err != nil {
			return err
		}
	}

	ts := []syscall.Timespec{timeToTimespec(hdr.AccessTime), timeToTimespec(hdr.ModTime)}
	// syscall.UtimesNano doesn't support a NOFOLLOW flag atm, and
	if hdr.Typeflag != tar.TypeSymlink {
		if err := system.UtimesNano(path, ts); err != nil && err != system.ErrNotSupportedPlatform {
			return err
		}
	} else {
		if err := system.LUtimesNano(path, ts); err != nil && err != system.ErrNotSupportedPlatform {
			return err
		}
	}
	return nil
}
Exemplo n.º 2
0
func (b *buildFile) runContextCommand(args string, allowRemote bool, allowDecompression bool, cmdName string) error {
	if b.context == nil {
		return fmt.Errorf("No context given. Impossible to use %s", cmdName)
	}
	tmp := strings.SplitN(args, " ", 2)
	if len(tmp) != 2 {
		return fmt.Errorf("Invalid %s format", cmdName)
	}

	orig, err := b.ReplaceEnvMatches(strings.Trim(tmp[0], " \t"))
	if err != nil {
		return err
	}

	dest, err := b.ReplaceEnvMatches(strings.Trim(tmp[1], " \t"))
	if err != nil {
		return err
	}

	cmd := b.config.Cmd
	b.config.Cmd = []string{"/bin/sh", "-c", fmt.Sprintf("#(nop) %s %s in %s", cmdName, orig, dest)}
	defer func(cmd []string) { b.config.Cmd = cmd }(cmd)
	b.config.Image = b.image

	var (
		origPath   = orig
		destPath   = dest
		remoteHash string
		isRemote   bool
		decompress = true
	)

	isRemote = utils.IsURL(orig)
	if isRemote && !allowRemote {
		return fmt.Errorf("Source can't be an URL for %s", cmdName)
	} else if utils.IsURL(orig) {
		// Initiate the download
		resp, err := utils.Download(orig)
		if err != nil {
			return err
		}

		// Create a tmp dir
		tmpDirName, err := ioutil.TempDir(b.contextPath, "docker-remote")
		if err != nil {
			return err
		}

		// Create a tmp file within our tmp dir
		tmpFileName := path.Join(tmpDirName, "tmp")
		tmpFile, err := os.OpenFile(tmpFileName, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
		if err != nil {
			return err
		}
		defer os.RemoveAll(tmpDirName)

		// Download and dump result to tmp file
		if _, err := io.Copy(tmpFile, resp.Body); err != nil {
			tmpFile.Close()
			return err
		}
		tmpFile.Close()

		// Remove the mtime of the newly created tmp file
		if err := system.UtimesNano(tmpFileName, make([]syscall.Timespec, 2)); err != nil {
			return err
		}

		origPath = path.Join(filepath.Base(tmpDirName), filepath.Base(tmpFileName))

		// Process the checksum
		r, err := archive.Tar(tmpFileName, archive.Uncompressed)
		if err != nil {
			return err
		}
		tarSum := &tarsum.TarSum{Reader: r, DisableCompression: true}
		if _, err := io.Copy(ioutil.Discard, tarSum); err != nil {
			return err
		}
		remoteHash = tarSum.Sum(nil)
		r.Close()

		// If the destination is a directory, figure out the filename.
		if strings.HasSuffix(dest, "/") {
			u, err := url.Parse(orig)
			if err != nil {
				return err
			}
			path := u.Path
			if strings.HasSuffix(path, "/") {
				path = path[:len(path)-1]
			}
			parts := strings.Split(path, "/")
			filename := parts[len(parts)-1]
			if filename == "" {
				return fmt.Errorf("cannot determine filename from url: %s", u)
			}
			destPath = dest + filename
		}
	}

	if err := b.checkPathForAddition(origPath); err != nil {
		return err
	}

	// Hash path and check the cache
	if b.utilizeCache {
		var (
			hash string
			sums = b.context.GetSums()
		)

		if remoteHash != "" {
			hash = remoteHash
		} else if fi, err := os.Stat(path.Join(b.contextPath, origPath)); err != nil {
			return err
		} else if fi.IsDir() {
			var subfiles []string
			for file, sum := range sums {
				absFile := path.Join(b.contextPath, file)
				absOrigPath := path.Join(b.contextPath, origPath)
				if strings.HasPrefix(absFile, absOrigPath) {
					subfiles = append(subfiles, sum)
				}
			}
			sort.Strings(subfiles)
			hasher := sha256.New()
			hasher.Write([]byte(strings.Join(subfiles, ",")))
			hash = "dir:" + hex.EncodeToString(hasher.Sum(nil))
		} else {
			if origPath[0] == '/' && len(origPath) > 1 {
				origPath = origPath[1:]
			}
			origPath = strings.TrimPrefix(origPath, "./")
			if h, ok := sums[origPath]; ok {
				hash = "file:" + h
			}
		}
		b.config.Cmd = []string{"/bin/sh", "-c", fmt.Sprintf("#(nop) %s %s in %s", cmdName, hash, dest)}
		hit, err := b.probeCache()
		if err != nil {
			return err
		}
		// If we do not have a hash, never use the cache
		if hit && hash != "" {
			return nil
		}
	}

	// Create the container
	container, _, err := b.daemon.Create(b.config, "")
	if err != nil {
		return err
	}
	b.tmpContainers[container.ID] = struct{}{}

	if err := container.Mount(); err != nil {
		return err
	}
	defer container.Unmount()

	if !allowDecompression || isRemote {
		decompress = false
	}
	if err := b.addContext(container, origPath, destPath, decompress); err != nil {
		return err
	}

	if err := b.commit(container.ID, cmd, fmt.Sprintf("%s %s in %s", cmdName, orig, dest)); err != nil {
		return err
	}
	return nil
}