From e6ccc740d8a5becc9d900b3fb459fbda0bd1c915 Mon Sep 17 00:00:00 2001
From: Pogobanane <aenderboy@gmx.de>
Date: Sun, 10 Jul 2022 15:29:55 +0200
Subject: [PATCH] darwin: impl SecureSymlinkChown

---
 pkgs/sops-install-secrets/darwin.go | 52 ++++++++++++++++++-----------
 1 file changed, 33 insertions(+), 19 deletions(-)

diff --git a/pkgs/sops-install-secrets/darwin.go b/pkgs/sops-install-secrets/darwin.go
index af1ff35..6e1c2de 100644
--- a/pkgs/sops-install-secrets/darwin.go
+++ b/pkgs/sops-install-secrets/darwin.go
@@ -3,29 +3,43 @@
 
 package main
 
-func SecureSymlinkChown(symlinkToCheck, expectedTarget string, owner, group int) error {
-	//fd, err := unix.Open(symlinkToCheck, unix.O_CLOEXEC|unix.O_PATH|unix.O_NOFOLLOW, 0)
-	//if err != nil {
-	//	return fmt.Errorf("Failed to open %s: %w", symlinkToCheck, err)
-	//}
-	//defer unix.Close(fd)
+import (
+	"fmt"
+	"os"
 
-	//buf := make([]byte, len(expectedTarget)+1) // oversize by one to detect trunc
-	//n, err := unix.Readlinkat(fd, "", buf)
-	//if err != nil {
-	//	return fmt.Errorf("couldn't readlinkat %s", symlinkToCheck)
-	//}
-	//if n > len(expectedTarget) || string(buf[:n]) != expectedTarget {
-	//	return fmt.Errorf("symlink %s does not point to %s", symlinkToCheck, expectedTarget)
-	//}
-	//err = unix.Fchownat(fd, "", owner, group, unix.AT_EMPTY_PATH)
-	//if err != nil {
-	//	return fmt.Errorf("cannot change owner of '%s' to %d/%d: %w", symlinkToCheck, owner, group, err)
-	//}
+	"golang.org/x/sys/unix"
+)
+
+func SecureSymlinkChown(symlinkToCheck string, expectedTarget string, owner, group int) error {
+	// not sure what O_PATH is needed for anyways
+	fd, err := unix.Open(symlinkToCheck, unix.O_CLOEXEC|unix.O_SYMLINK|unix.O_NOFOLLOW, 0)
+	if err != nil {
+		return fmt.Errorf("Failed to open %s: %w", symlinkToCheck, err)
+	}
+	defer unix.Close(fd)
+
+	buf := make([]byte, len(expectedTarget)+1) // oversize by one to detect trunc
+	n, err := unix.Readlinkat(fd, "", buf)
+	if err != nil {
+		return fmt.Errorf("couldn't readlinkat %s", symlinkToCheck)
+	}
+	if n > len(expectedTarget) || string(buf[:n]) != expectedTarget {
+		return fmt.Errorf("symlink %s does not point to %s", symlinkToCheck, expectedTarget)
+	}
+	err = unix.Fchownat(fd, "", owner, group, unix.AT_SYMLINK_NOFOLLOW)
+	if err != nil {
+		return fmt.Errorf("cannot change owner of '%s' to %d/%d: %w", symlinkToCheck, owner, group, err)
+	}
 	return nil
 }
 
-func MountSecretFs(mountpoint string, keysGid int) error {
+// NUMSECTORS=128000       # a sector is 512 bytes
+// mydev=`hdiutil attach -nomount ram://$NUMSECTORS`
+// newfs_hfs $mydev
+// mkdir /tmp/mymount
+// mount -t hfs $mydev /tmp/mymount
+
+func MountSecretFs(mountpoint string, keysGid int, userMode bool) error {
 	//if err := os.MkdirAll(mountpoint, 0751); err != nil {
 	//	return fmt.Errorf("Cannot create directory '%s': %w", mountpoint, err)
 	//}