fix: Fix Windows support (aquasecurity#481)

* fix: Fix Windows support

Signed-off-by: Liam Galvin <liam.galvin@aquasec.com>

* Update writable.go

* Update writable_windows.go

pkg/scanners/terraform/parser/resolvers/cache.go

@@ -7,8 +7,6 @@ import (
 	"io/fs"
 	"os"
 	"path/filepath"
-
-	"golang.org/x/sys/unix"
 )
 
 type cacheResolver struct{}
@@ -43,17 +41,13 @@ func cacheDir() string {
 		if err := os.MkdirAll(attempt, 0o755); err != nil {
 			continue
 		}
-		if writable(attempt) {
+		if isWritable(attempt) {
 			return attempt
 		}
 	}
 	return ""
 }
 
-func writable(path string) bool {
-	return unix.Access(path, unix.W_OK) == nil
-}
-
 func (r *cacheResolver) Resolve(_ context.Context, _ fs.FS, opt Options) (filesystem fs.FS, prefix string, downloadPath string, applies bool, err error) {
 	if !opt.AllowCache {
 		opt.Debug("Cache is disabled.")

pkg/scanners/terraform/parser/resolvers/writable.go

@@ -0,0 +1,36 @@
+//go:build !windows
+// +build !windows
+
+package resolvers
+
+import (
+	"os"
+	"syscall"
+)
+
+func isWritable(path string) bool {
+	info, err := os.Stat(path)
+	if err != nil {
+		return false
+	}
+
+	if !info.IsDir() {
+		return false
+	}
+
+	// Check if the user bit is enabled in file permission
+	if info.Mode().Perm()&(1<<(uint(7))) == 0 {
+		return false
+	}
+
+	var stat syscall.Stat_t
+	if err = syscall.Stat(path, &stat); err != nil {
+		return false
+	}
+
+	if uint32(os.Geteuid()) != stat.Uid {
+		return false
+	}
+
+	return true
+}

pkg/scanners/terraform/parser/resolvers/writable_windows.go

@@ -0,0 +1,24 @@
+package resolvers
+
+import (
+	"os"
+)
+
+func isWritable(path string) bool {
+
+	info, err := os.Stat(path)
+	if err != nil {
+		return false
+	}
+
+	if !info.IsDir() {
+		return false
+	}
+
+	// Check if the user bit is enabled in file permission
+	if info.Mode().Perm()&(1<<(uint(7))) == 0 {
+		return false
+	}
+
+	return true
+}