vendor/github.com/hashicorp/go-getter/decompress.go

   1 package getter
   2
   3 import (
   4         "strings"
   5 )
   6
   7 // Decompressor defines the interface that must be implemented to add
   8 // support for decompressing a type.
   9 //
  10 // Important: if you're implementing a decompressor, please use the
  11 // containsDotDot helper in this file to ensure that files can't be
  12 // decompressed outside of the specified directory.
  13 type Decompressor interface {
  14         // Decompress should decompress src to dst. dir specifies whether dst
  15         // is a directory or single file. src is guaranteed to be a single file
  16         // that exists. dst is not guaranteed to exist already.
  17         Decompress(dst, src string, dir bool) error
  18 }
  19
  20 // Decompressors is the mapping of extension to the Decompressor implementation
  21 // that will decompress that extension/type.
  22 var Decompressors map[string]Decompressor
  23
  24 func init() {
  25         tbzDecompressor := new(TarBzip2Decompressor)
  26         tgzDecompressor := new(TarGzipDecompressor)
  27         txzDecompressor := new(TarXzDecompressor)
  28
  29         Decompressors = map[string]Decompressor{
  30                 "bz2":     new(Bzip2Decompressor),
  31                 "gz":      new(GzipDecompressor),
  32                 "xz":      new(XzDecompressor),
  33                 "tar.bz2": tbzDecompressor,
  34                 "tar.gz":  tgzDecompressor,
  35                 "tar.xz":  txzDecompressor,
  36                 "tbz2":    tbzDecompressor,
  37                 "tgz":     tgzDecompressor,
  38                 "txz":     txzDecompressor,
  39                 "zip":     new(ZipDecompressor),
  40         }
  41 }
  42
  43 // containsDotDot checks if the filepath value v contains a ".." entry.
  44 // This will check filepath components by splitting along / or \. This
  45 // function is copied directly from the Go net/http implementation.
  46 func containsDotDot(v string) bool {
  47         if !strings.Contains(v, "..") {
  48                 return false
  49         }
  50         for _, ent := range strings.FieldsFunc(v, isSlashRune) {
  51                 if ent == ".." {
  52                         return true
  53                 }
  54         }
  55         return false
  56 }
  57
  58 func isSlashRune(r rune) bool { return r == '/' || r == '\\' }