From 2fe3de16befda10563cd78aedd5df5751e3805b5 Mon Sep 17 00:00:00 2001
From: Michael Schurter <schmichael@hashicorp.com>
Date: Wed, 12 Apr 2017 12:31:00 -0700
Subject: [PATCH 1/4] Chown files when copying into chroot

Fixes #2552

Not needed when hardlinking. Only adds Linux support but other OS's may
be easy.
---
 client/allocdir/alloc_dir.go  | 12 ++++++++++--
 client/allocdir/fs_darwin.go  |  5 +++++
 client/allocdir/fs_freebsd.go |  5 +++++
 client/allocdir/fs_linux.go   |  8 ++++++++
 client/allocdir/fs_solaris.go |  5 +++++
 client/allocdir/fs_unix.go    | 10 +++++-----
 client/allocdir/fs_windows.go |  9 +++++++--
 client/allocdir/task_dir.go   |  6 ++++--
 8 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/client/allocdir/alloc_dir.go b/client/allocdir/alloc_dir.go
index bbdb6431798..8c95d0c7509 100644
--- a/client/allocdir/alloc_dir.go
+++ b/client/allocdir/alloc_dir.go
@@ -385,7 +385,9 @@ func getFileWatcher(path string) watch.FileWatcher {
 	return watch.NewPollingFileWatcher(path)
 }
 
-func fileCopy(src, dst string, perm os.FileMode) error {
+// fileCopy from src to dst setting the permissions and owner (if uid & gid are
+// both greater than 0)
+func fileCopy(src, dst string, uid, gid int, perm os.FileMode) error {
 	// Do a simple copy.
 	srcFile, err := os.Open(src)
 	if err != nil {
@@ -400,7 +402,13 @@ func fileCopy(src, dst string, perm os.FileMode) error {
 	defer dstFile.Close()
 
 	if _, err := io.Copy(dstFile, srcFile); err != nil {
-		return fmt.Errorf("Couldn't copy %v to %v: %v", src, dst, err)
+		return fmt.Errorf("Couldn't copy %q to %q: %v", src, dst, err)
+	}
+
+	if uid >= 0 && gid >= 0 {
+		if err := dstFile.Chown(uid, gid); err != nil {
+			return fmt.Errorf("Couldn't copy %q to %q: %v", src, dst, err)
+		}
 	}
 
 	return nil
diff --git a/client/allocdir/fs_darwin.go b/client/allocdir/fs_darwin.go
index fe29791c460..7cd5caf23b4 100644
--- a/client/allocdir/fs_darwin.go
+++ b/client/allocdir/fs_darwin.go
@@ -24,3 +24,8 @@ func createSecretDir(dir string) error {
 func removeSecretDir(dir string) error {
 	return os.RemoveAll(dir)
 }
+
+// getOwner isn't implemented for Darwin
+func getOwner(os.FileInfo) (int, int) {
+	return -1, -1
+}
diff --git a/client/allocdir/fs_freebsd.go b/client/allocdir/fs_freebsd.go
index fe29791c460..0d34925a7af 100644
--- a/client/allocdir/fs_freebsd.go
+++ b/client/allocdir/fs_freebsd.go
@@ -24,3 +24,8 @@ func createSecretDir(dir string) error {
 func removeSecretDir(dir string) error {
 	return os.RemoveAll(dir)
 }
+
+// getOwner isn't implemented for FreeBSD
+func getOwner(os.FileInfo) (int, int) {
+	return -1, -1
+}
diff --git a/client/allocdir/fs_linux.go b/client/allocdir/fs_linux.go
index 7a76c5dd1a0..c6b079f867a 100644
--- a/client/allocdir/fs_linux.go
+++ b/client/allocdir/fs_linux.go
@@ -88,3 +88,11 @@ func removeSecretDir(dir string) error {
 	}
 	return os.RemoveAll(dir)
 }
+
+func getOwner(fi os.FileInfo) (int, int) {
+	stat, ok := fi.Sys().(*syscall.Stat_t)
+	if !ok {
+		return -1, -1
+	}
+	return int(stat.Uid), int(stat.Gid)
+}
diff --git a/client/allocdir/fs_solaris.go b/client/allocdir/fs_solaris.go
index 088b58f5b3f..83359b1b3aa 100644
--- a/client/allocdir/fs_solaris.go
+++ b/client/allocdir/fs_solaris.go
@@ -25,3 +25,8 @@ func createSecretDir(dir string) error {
 func removeSecretDir(dir string) error {
 	return os.RemoveAll(dir)
 }
+
+// getOwner isn't implemented for Solaris
+func getOwner(os.FileInfo) (int, int) {
+	return -1, -1
+}
diff --git a/client/allocdir/fs_unix.go b/client/allocdir/fs_unix.go
index 648fce1adb6..7e3068b3bc9 100644
--- a/client/allocdir/fs_unix.go
+++ b/client/allocdir/fs_unix.go
@@ -82,7 +82,7 @@ func getGid(u *user.User) (int, error) {
 
 // linkOrCopy attempts to hardlink dst to src and fallsback to copying if the
 // hardlink fails.
-func linkOrCopy(src, dst string, perm os.FileMode) error {
+func linkOrCopy(src, dst string, uid, gid int, perm os.FileMode) error {
 	// Avoid link/copy if the file already exists in the chroot
 	// TODO 0.6 clean this up. This was needed because chroot creation fails
 	// when a process restarts.
@@ -90,9 +90,9 @@ func linkOrCopy(src, dst string, perm os.FileMode) error {
 		return nil
 	}
 	// Attempt to hardlink.
-	if err := os.Link(src, dst); err == nil {
-		return nil
-	}
+	//if err := os.Link(src, dst); err == nil {
+	//	return nil
+	//}
 
-	return fileCopy(src, dst, perm)
+	return fileCopy(src, dst, uid, gid, perm)
 }
diff --git a/client/allocdir/fs_windows.go b/client/allocdir/fs_windows.go
index de0fcec898c..f39f2cd72f3 100644
--- a/client/allocdir/fs_windows.go
+++ b/client/allocdir/fs_windows.go
@@ -21,8 +21,8 @@ var (
 )
 
 // linkOrCopy is always copies dst to src on Windows.
-func linkOrCopy(src, dst string, perm os.FileMode) error {
-	return fileCopy(src, dst, perm)
+func linkOrCopy(src, dst string, uid, gid int, perm os.FileMode) error {
+	return fileCopy(src, dst, uid, gid, perm)
 }
 
 // The windows version does nothing currently.
@@ -70,3 +70,8 @@ func MountSpecialDirs(taskDir string) error {
 func unmountSpecialDirs(taskDir string) error {
 	return nil
 }
+
+// getOwner doesn't work on Windows as Windows doesn't use int user IDs
+func getOwner(os.FileInfo) (int, int) {
+	return -1, -1
+}
diff --git a/client/allocdir/task_dir.go b/client/allocdir/task_dir.go
index 4f2817e625c..b4376057213 100644
--- a/client/allocdir/task_dir.go
+++ b/client/allocdir/task_dir.go
@@ -163,7 +163,8 @@ func (t *TaskDir) embedDirs(entries map[string]string) error {
 
 			// Copy the file.
 			taskEntry := filepath.Join(t.Dir, dest)
-			if err := linkOrCopy(source, taskEntry, s.Mode().Perm()); err != nil {
+			uid, gid := getOwner(s)
+			if err := linkOrCopy(source, taskEntry, uid, gid, s.Mode().Perm()); err != nil {
 				return err
 			}
 
@@ -217,7 +218,8 @@ func (t *TaskDir) embedDirs(entries map[string]string) error {
 				continue
 			}
 
-			if err := linkOrCopy(hostEntry, taskEntry, entry.Mode().Perm()); err != nil {
+			uid, gid := getOwner(entry)
+			if err := linkOrCopy(hostEntry, taskEntry, uid, gid, entry.Mode().Perm()); err != nil {
 				return err
 			}
 		}

From 1cffc7310ee300d2eefa5dbcf236cbec9a9f072d Mon Sep 17 00:00:00 2001
From: Michael Schurter <schmichael@hashicorp.com>
Date: Wed, 12 Apr 2017 13:58:50 -0700
Subject: [PATCH 2/4] Don't disable hardlinking!

---
 client/allocdir/fs_unix.go | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/client/allocdir/fs_unix.go b/client/allocdir/fs_unix.go
index 7e3068b3bc9..e3672452d83 100644
--- a/client/allocdir/fs_unix.go
+++ b/client/allocdir/fs_unix.go
@@ -90,9 +90,9 @@ func linkOrCopy(src, dst string, uid, gid int, perm os.FileMode) error {
 		return nil
 	}
 	// Attempt to hardlink.
-	//if err := os.Link(src, dst); err == nil {
-	//	return nil
-	//}
+	if err := os.Link(src, dst); err == nil {
+		return nil
+	}
 
 	return fileCopy(src, dst, uid, gid, perm)
 }

From 17471bf7c0742e982106f0e63808a6c2c54ec4ab Mon Sep 17 00:00:00 2001
From: Michael Schurter <schmichael@hashicorp.com>
Date: Mon, 17 Apr 2017 12:29:34 -0700
Subject: [PATCH 3/4] Set ownership on directories in chroot

Also support getOwner on all Unixes as they all have `Stat_t.{U,G}id`
---
 client/allocdir/alloc_dir.go  | 34 +++++++++++++++++++++++++++-------
 client/allocdir/fs_darwin.go  |  5 -----
 client/allocdir/fs_freebsd.go |  5 -----
 client/allocdir/fs_linux.go   |  8 --------
 client/allocdir/fs_solaris.go |  5 -----
 client/allocdir/fs_unix.go    |  9 +++++++++
 client/allocdir/fs_windows.go |  2 +-
 7 files changed, 37 insertions(+), 31 deletions(-)

diff --git a/client/allocdir/alloc_dir.go b/client/allocdir/alloc_dir.go
index 8c95d0c7509..dd665926112 100644
--- a/client/allocdir/alloc_dir.go
+++ b/client/allocdir/alloc_dir.go
@@ -17,6 +17,12 @@ import (
 	"github.com/hpcloud/tail/watch"
 )
 
+const (
+	// idUnsupported is what the uid/gid will be set to on platforms (eg
+	// Windows) that don't support integer ownership identifiers.
+	idUnsupported = -1
+)
+
 var (
 	// The name of the directory that is shared across tasks in a task group.
 	SharedAllocName = "alloc"
@@ -405,7 +411,7 @@ func fileCopy(src, dst string, uid, gid int, perm os.FileMode) error {
 		return fmt.Errorf("Couldn't copy %q to %q: %v", src, dst, err)
 	}
 
-	if uid >= 0 && gid >= 0 {
+	if uid != idUnsupported && gid != idUnsupported {
 		if err := dstFile.Chown(uid, gid); err != nil {
 			return fmt.Errorf("Couldn't copy %q to %q: %v", src, dst, err)
 		}
@@ -456,6 +462,12 @@ func createDir(basePath, relPath string) error {
 		if err := os.MkdirAll(destDir, fi.Perm); err != nil {
 			return err
 		}
+
+		if fi.Uid != idUnsupported && fi.Gid != idUnsupported {
+			if err := os.Chown(destDir, fi.Uid, fi.Gid); err != nil {
+				return err
+			}
+		}
 	}
 	return nil
 }
@@ -464,6 +476,10 @@ func createDir(basePath, relPath string) error {
 type fileInfo struct {
 	Name string
 	Perm os.FileMode
+
+	// Uid and Gid are unsupported on Windows
+	Uid int
+	Gid int
 }
 
 // splitPath stats each subdirectory of a path. The first element of the array
@@ -471,17 +487,19 @@ type fileInfo struct {
 // path.
 func splitPath(path string) ([]fileInfo, error) {
 	var mode os.FileMode
-	i, err := os.Stat(path)
+	fi, err := os.Stat(path)
 
 	// If the path is not present in the host then we respond with the most
 	// flexible permission.
+	uid, gid := idUnsupported, idUnsupported
 	if err != nil {
 		mode = os.ModePerm
 	} else {
-		mode = i.Mode()
+		uid, gid = getOwner(fi)
+		mode = fi.Mode()
 	}
 	var dirs []fileInfo
-	dirs = append(dirs, fileInfo{Name: path, Perm: mode})
+	dirs = append(dirs, fileInfo{Name: path, Perm: mode, Uid: uid, Gid: gid})
 	currentDir := path
 	for {
 		dir := filepath.Dir(filepath.Clean(currentDir))
@@ -491,13 +509,15 @@ func splitPath(path string) ([]fileInfo, error) {
 
 		// We try to find the permission of the file in the host. If the path is not
 		// present in the host then we respond with the most flexible permission.
-		i, err = os.Stat(dir)
+		uid, gid := idUnsupported, idUnsupported
+		fi, err := os.Stat(dir)
 		if err != nil {
 			mode = os.ModePerm
 		} else {
-			mode = i.Mode()
+			uid, gid = getOwner(fi)
+			mode = fi.Mode()
 		}
-		dirs = append(dirs, fileInfo{Name: dir, Perm: mode})
+		dirs = append(dirs, fileInfo{Name: dir, Perm: mode, Uid: uid, Gid: gid})
 		currentDir = dir
 	}
 	return dirs, nil
diff --git a/client/allocdir/fs_darwin.go b/client/allocdir/fs_darwin.go
index 7cd5caf23b4..fe29791c460 100644
--- a/client/allocdir/fs_darwin.go
+++ b/client/allocdir/fs_darwin.go
@@ -24,8 +24,3 @@ func createSecretDir(dir string) error {
 func removeSecretDir(dir string) error {
 	return os.RemoveAll(dir)
 }
-
-// getOwner isn't implemented for Darwin
-func getOwner(os.FileInfo) (int, int) {
-	return -1, -1
-}
diff --git a/client/allocdir/fs_freebsd.go b/client/allocdir/fs_freebsd.go
index 0d34925a7af..fe29791c460 100644
--- a/client/allocdir/fs_freebsd.go
+++ b/client/allocdir/fs_freebsd.go
@@ -24,8 +24,3 @@ func createSecretDir(dir string) error {
 func removeSecretDir(dir string) error {
 	return os.RemoveAll(dir)
 }
-
-// getOwner isn't implemented for FreeBSD
-func getOwner(os.FileInfo) (int, int) {
-	return -1, -1
-}
diff --git a/client/allocdir/fs_linux.go b/client/allocdir/fs_linux.go
index c6b079f867a..7a76c5dd1a0 100644
--- a/client/allocdir/fs_linux.go
+++ b/client/allocdir/fs_linux.go
@@ -88,11 +88,3 @@ func removeSecretDir(dir string) error {
 	}
 	return os.RemoveAll(dir)
 }
-
-func getOwner(fi os.FileInfo) (int, int) {
-	stat, ok := fi.Sys().(*syscall.Stat_t)
-	if !ok {
-		return -1, -1
-	}
-	return int(stat.Uid), int(stat.Gid)
-}
diff --git a/client/allocdir/fs_solaris.go b/client/allocdir/fs_solaris.go
index 83359b1b3aa..088b58f5b3f 100644
--- a/client/allocdir/fs_solaris.go
+++ b/client/allocdir/fs_solaris.go
@@ -25,8 +25,3 @@ func createSecretDir(dir string) error {
 func removeSecretDir(dir string) error {
 	return os.RemoveAll(dir)
 }
-
-// getOwner isn't implemented for Solaris
-func getOwner(os.FileInfo) (int, int) {
-	return -1, -1
-}
diff --git a/client/allocdir/fs_unix.go b/client/allocdir/fs_unix.go
index e3672452d83..77447a32f7f 100644
--- a/client/allocdir/fs_unix.go
+++ b/client/allocdir/fs_unix.go
@@ -8,6 +8,7 @@ import (
 	"os/user"
 	"path/filepath"
 	"strconv"
+	"syscall"
 
 	"golang.org/x/sys/unix"
 )
@@ -96,3 +97,11 @@ func linkOrCopy(src, dst string, uid, gid int, perm os.FileMode) error {
 
 	return fileCopy(src, dst, uid, gid, perm)
 }
+
+func getOwner(fi os.FileInfo) (int, int) {
+	stat, ok := fi.Sys().(*syscall.Stat_t)
+	if !ok {
+		return -1, -1
+	}
+	return int(stat.Uid), int(stat.Gid)
+}
diff --git a/client/allocdir/fs_windows.go b/client/allocdir/fs_windows.go
index f39f2cd72f3..3667c1953bb 100644
--- a/client/allocdir/fs_windows.go
+++ b/client/allocdir/fs_windows.go
@@ -73,5 +73,5 @@ func unmountSpecialDirs(taskDir string) error {
 
 // getOwner doesn't work on Windows as Windows doesn't use int user IDs
 func getOwner(os.FileInfo) (int, int) {
-	return -1, -1
+	return idUnsupported, idUnsupported
 }

From 75c3863533e2f550203d139d8d752a8dbeb96080 Mon Sep 17 00:00:00 2001
From: Michael Schurter <schmichael@hashicorp.com>
Date: Wed, 19 Apr 2017 12:37:15 -0700
Subject: [PATCH 4/4] Add #2552 / #2553 to changelog

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index de933e8a8fa..cba97c6ee28 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ BUG FIXES:
  * client/artifact: Honor netrc [GH-2524]
  * client/artifact: Handle tars where file in directory is listed before
    directory [GH-2524]
+ * driver/exec: Properly set file/dir ownership in chroots [GH-2552]
  * server: Reject non-TLS clients when TLS enabled [GH-2525]
  * server: Fix a panic in plan evaluation with partial failures and all_at_once
    set [GH-2544]