Merge pull request #256 from hashicorp/f-umask-master-may-2020

umask final version against master (again)

Author: Mahmood Ali

client.go

@@ -39,6 +39,10 @@ type Client struct {
 	// for documentation.
 	Mode ClientMode
 
+	// Umask is used to mask file permissions when storing local files or decompressing
+	// an archive
+	Umask os.FileMode
+
 	// Detectors is the list of detectors that are tried on the source.
 	// If this is nil, then the default Detectors will be used.
 	Detectors []Detector
@@ -66,6 +70,20 @@ type Client struct {
 	Options []ClientOption
 }
 
+// umask returns the effective umask for the Client, defaulting to the process umask
+func (c *Client) umask() os.FileMode {
+	if c == nil {
+		return 0
+	}
+	return c.Umask
+}
+
+// mode returns file mode umasked by the Client umask
+func (c *Client) mode(mode os.FileMode) os.FileMode {
+	m := mode & ^c.umask()
+	return m
+}
+
 // Get downloads the configured source to the destination.
 func (c *Client) Get() error {
 	if err := c.Configure(c.Options...); err != nil {
@@ -233,7 +251,7 @@ func (c *Client) Get() error {
 		if decompressor != nil {
 			// We have a decompressor, so decompress the current destination
 			// into the final destination with the proper mode.
-			err := decompressor.Decompress(decompressDst, dst, decompressDir)
+			err := decompressor.Decompress(decompressDst, dst, decompressDir, c.umask())
 			if err != nil {
 				return err
 			}
@@ -281,7 +299,7 @@ func (c *Client) Get() error {
 		if err := os.RemoveAll(realDst); err != nil {
 			return err
 		}
-		if err := os.MkdirAll(realDst, 0755); err != nil {
+		if err := os.MkdirAll(realDst, c.mode(0755)); err != nil {
 			return err
 		}
 
@@ -291,7 +309,7 @@ func (c *Client) Get() error {
 			return err
 		}
 
-		return copyDir(c.Ctx, realDst, subDir, false)
+		return copyDir(c.Ctx, realDst, subDir, false, c.umask())
 	}
 
 	return nil

copy_dir.go

@@ -7,11 +7,16 @@ import (
 	"strings"
 )
 
+// mode returns the file mode masked by the umask
+func mode(mode, umask os.FileMode) os.FileMode {
+	return mode & ^umask
+}
+
 // copyDir copies the src directory contents into dst. Both directories
 // should already exist.
 //
 // If ignoreDot is set to true, then dot-prefixed files/folders are ignored.
-func copyDir(ctx context.Context, dst string, src string, ignoreDot bool) error {
+func copyDir(ctx context.Context, dst string, src string, ignoreDot bool, umask os.FileMode) error {
 	src, err := filepath.EvalSymlinks(src)
 	if err != nil {
 		return err
@@ -46,32 +51,16 @@ func copyDir(ctx context.Context, dst string, src string, ignoreDot bool) error
 				return nil
 			}
 
-			if err := os.MkdirAll(dstPath, 0755); err != nil {
+			if err := os.MkdirAll(dstPath, mode(0755, umask)); err != nil {
 				return err
 			}
 
 			return nil
 		}
 
 		// If we have a file, copy the contents.
-		srcF, err := os.Open(path)
-		if err != nil {
-			return err
-		}
-		defer srcF.Close()
-
-		dstF, err := os.Create(dstPath)
-		if err != nil {
-			return err
-		}
-		defer dstF.Close()
-
-		if _, err := Copy(ctx, dstF, srcF); err != nil {
-			return err
-		}
-
-		// Chmod it
-		return os.Chmod(dstPath, info.Mode())
+		_, err = copyFile(ctx, dstPath, path, info.Mode(), umask)
+		return err
 	}
 
 	return filepath.Walk(src, walkFn)

decompress.go

@@ -1,6 +1,7 @@
 package getter
 
 import (
+	"os"
 	"strings"
 )
 
@@ -14,7 +15,7 @@ type Decompressor interface {
 	// Decompress should decompress src to dst. dir specifies whether dst
 	// is a directory or single file. src is guaranteed to be a single file
 	// that exists. dst is not guaranteed to exist already.
-	Decompress(dst, src string, dir bool) error
+	Decompress(dst, src string, dir bool, umask os.FileMode) error
 }
 
 // Decompressors is the mapping of extension to the Decompressor implementation

decompress_bzip2.go

@@ -3,7 +3,6 @@ package getter
 import (
 	"compress/bzip2"
 	"fmt"
-	"io"
 	"os"
 	"path/filepath"
 )
@@ -12,14 +11,14 @@ import (
 // decompress bz2 files.
 type Bzip2Decompressor struct{}
 
-func (d *Bzip2Decompressor) Decompress(dst, src string, dir bool) error {
+func (d *Bzip2Decompressor) Decompress(dst, src string, dir bool, umask os.FileMode) error {
 	// Directory isn't supported at all
 	if dir {
 		return fmt.Errorf("bzip2-compressed files can only unarchive to a single file")
 	}
 
 	// If we're going into a directory we should make that first
-	if err := os.MkdirAll(filepath.Dir(dst), 0755); err != nil {
+	if err := os.MkdirAll(filepath.Dir(dst), mode(0755, umask)); err != nil {
 		return err
 	}
 
@@ -34,12 +33,5 @@ func (d *Bzip2Decompressor) Decompress(dst, src string, dir bool) error {
 	bzipR := bzip2.NewReader(f)
 
 	// Copy it out
-	dstF, err := os.Create(dst)
-	if err != nil {
-		return err
-	}
-	defer dstF.Close()
-
-	_, err = io.Copy(dstF, bzipR)
-	return err
+	return copyReader(dst, bzipR, 0622, umask)
 }

decompress_gzip.go

@@ -3,7 +3,6 @@ package getter
 import (
 	"compress/gzip"
 	"fmt"
-	"io"
 	"os"
 	"path/filepath"
 )
@@ -12,14 +11,14 @@ import (
 // decompress gzip files.
 type GzipDecompressor struct{}
 
-func (d *GzipDecompressor) Decompress(dst, src string, dir bool) error {
+func (d *GzipDecompressor) Decompress(dst, src string, dir bool, umask os.FileMode) error {
 	// Directory isn't supported at all
 	if dir {
 		return fmt.Errorf("gzip-compressed files can only unarchive to a single file")
 	}
 
 	// If we're going into a directory we should make that first
-	if err := os.MkdirAll(filepath.Dir(dst), 0755); err != nil {
+	if err := os.MkdirAll(filepath.Dir(dst), mode(0755, umask)); err != nil {
 		return err
 	}
 
@@ -38,12 +37,5 @@ func (d *GzipDecompressor) Decompress(dst, src string, dir bool) error {
 	defer gzipR.Close()
 
 	// Copy it out
-	dstF, err := os.Create(dst)
-	if err != nil {
-		return err
-	}
-	defer dstF.Close()
-
-	_, err = io.Copy(dstF, gzipR)
-	return err
+	return copyReader(dst, gzipR, 0622, umask)
 }

decompress_tar.go

@@ -11,7 +11,7 @@ import (
 
 // untar is a shared helper for untarring an archive. The reader should provide
 // an uncompressed view of the tar archive.
-func untar(input io.Reader, dst, src string, dir bool) error {
+func untar(input io.Reader, dst, src string, dir bool, umask os.FileMode) error {
 	tarR := tar.NewReader(input)
 	done := false
 	dirHdrs := []*tar.Header{}
@@ -51,7 +51,7 @@ func untar(input io.Reader, dst, src string, dir bool) error {
 			}
 
 			// A directory, just make the directory and continue unarchiving...
-			if err := os.MkdirAll(path, 0755); err != nil {
+			if err := os.MkdirAll(path, mode(0755, umask)); err != nil {
 				return err
 			}
 
@@ -67,7 +67,7 @@ func untar(input io.Reader, dst, src string, dir bool) error {
 
 			// Check that the directory exists, otherwise create it
 			if _, err := os.Stat(dstPath); os.IsNotExist(err) {
-				if err := os.MkdirAll(dstPath, 0755); err != nil {
+				if err := os.MkdirAll(dstPath, mode(0755, umask)); err != nil {
 					return err
 				}
 			}
@@ -82,20 +82,10 @@ func untar(input io.Reader, dst, src string, dir bool) error {
 		done = true
 
 		// Open the file for writing
-		dstF, err := os.Create(path)
+		err = copyReader(path, tarR, hdr.FileInfo().Mode(), umask)
 		if err != nil {
 			return err
 		}
-		_, err = io.Copy(dstF, tarR)
-		dstF.Close()
-		if err != nil {
-			return err
-		}
-
-		// Chmod the file
-		if err := os.Chmod(path, hdr.FileInfo().Mode()); err != nil {
-			return err
-		}
 
 		// Set the access and modification time if valid, otherwise default to current time
 		aTime := now
@@ -115,7 +105,7 @@ func untar(input io.Reader, dst, src string, dir bool) error {
 	for _, dirHdr := range dirHdrs {
 		path := filepath.Join(dst, dirHdr.Name)
 		// Chmod the directory since they might be created before we know the mode flags
-		if err := os.Chmod(path, dirHdr.FileInfo().Mode()); err != nil {
+		if err := os.Chmod(path, mode(dirHdr.FileInfo().Mode(), umask)); err != nil {
 			return err
 		}
 		// Set the mtime/atime attributes since they would have been changed during extraction
@@ -139,13 +129,13 @@ func untar(input io.Reader, dst, src string, dir bool) error {
 // unpack tar files.
 type tarDecompressor struct{}
 
-func (d *tarDecompressor) Decompress(dst, src string, dir bool) error {
+func (d *tarDecompressor) Decompress(dst, src string, dir bool, umask os.FileMode) error {
 	// If we're going into a directory we should make that first
 	mkdir := dst
 	if !dir {
 		mkdir = filepath.Dir(dst)
 	}
-	if err := os.MkdirAll(mkdir, 0755); err != nil {
+	if err := os.MkdirAll(mkdir, mode(0755, umask)); err != nil {
 		return err
 	}
 
@@ -156,5 +146,5 @@ func (d *tarDecompressor) Decompress(dst, src string, dir bool) error {
 	}
 	defer f.Close()
 
-	return untar(f, dst, src, dir)
+	return untar(f, dst, src, dir, umask)
 }

decompress_tar_test.go

@@ -1,7 +1,10 @@
 package getter
 
 import (
+	"io/ioutil"
+	"os"
 	"path/filepath"
+	"runtime"
 	"testing"
 	"time"
 )
@@ -41,3 +44,64 @@ func TestTar(t *testing.T) {
 
 	TestDecompressor(t, new(tarDecompressor), cases)
 }
+
+// testDecompressPermissions decompresses a directory and checks the permissions of the expanded files
+func testDecompressorPermissions(t *testing.T, d Decompressor, input string, expected map[string]int, umask os.FileMode) {
+	td, err := ioutil.TempDir("", "getter")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Destination is always joining result so that we have a new path
+	dst := filepath.Join(td, "subdir", "result")
+
+	err = d.Decompress(dst, input, true, umask)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	defer os.RemoveAll(dst)
+
+	for name, mode := range expected {
+		fi, err := os.Stat(filepath.Join(dst, name))
+		if err != nil {
+			t.Fatalf("err: %s", err)
+		}
+
+		real := fi.Mode()
+		if real != os.FileMode(mode) {
+			t.Fatalf("err: %s expected mode %o got %o", name, mode, real)
+		}
+	}
+}
+
+func TestDecompressTarPermissions(t *testing.T) {
+	d := new(tarDecompressor)
+	input := "./test-fixtures/decompress-tar/permissions.tar"
+
+	var expected map[string]int
+	var masked int
+
+	if runtime.GOOS == "windows" {
+		expected = map[string]int{
+			"directory/public":  0666,
+			"directory/private": 0666,
+			"directory/exec":    0666,
+			"directory/setuid":  0666,
+		}
+		masked = 0666
+	} else {
+		expected = map[string]int{
+			"directory/public":  0666,
+			"directory/private": 0600,
+			"directory/exec":    0755,
+			"directory/setuid":  040000755,
+		}
+		masked = 0755
+	}
+
+	testDecompressorPermissions(t, d, input, expected, os.FileMode(0))
+
+	expected["directory/setuid"] = masked
+	testDecompressorPermissions(t, d, input, expected, os.FileMode(060000000))
+}

decompress_tbz2.go

@@ -10,13 +10,13 @@ import (
 // decompress tar.bz2 files.
 type TarBzip2Decompressor struct{}
 
-func (d *TarBzip2Decompressor) Decompress(dst, src string, dir bool) error {
+func (d *TarBzip2Decompressor) Decompress(dst, src string, dir bool, umask os.FileMode) error {
 	// If we're going into a directory we should make that first
 	mkdir := dst
 	if !dir {
 		mkdir = filepath.Dir(dst)
 	}
-	if err := os.MkdirAll(mkdir, 0755); err != nil {
+	if err := os.MkdirAll(mkdir, mode(0755, umask)); err != nil {
 		return err
 	}
 
@@ -29,5 +29,5 @@ func (d *TarBzip2Decompressor) Decompress(dst, src string, dir bool) error {
 
 	// Bzip2 compression is second
 	bzipR := bzip2.NewReader(f)
-	return untar(bzipR, dst, src, dir)
+	return untar(bzipR, dst, src, dir, umask)
 }

decompress_testing.go

@@ -47,7 +47,7 @@ func TestDecompressor(t testing.T, d Decompressor, cases []TestDecompressCase) {
 			defer os.RemoveAll(td)
 
 			// Decompress
-			err := d.Decompress(dst, tc.Input, tc.Dir)
+			err := d.Decompress(dst, tc.Input, tc.Dir, 0022)
 			if (err != nil) != tc.Err {
 				t.Fatalf("err %s: %s", tc.Input, err)
 			}