new: new caplets module to manage system caplets

core/core.go

@@ -1,7 +1,9 @@
 package core
 
 import (
+	"archive/zip"
 	"fmt"
+	"io"
 	"os"
 	"os/exec"
 	"os/user"
@@ -102,3 +104,48 @@ func ExpandPath(path string) (string, error) {
 	}
 	return "", nil
 }
+
+// Unzip will decompress a zip archive, moving all files and folders
+// within the zip file (parameter 1) to an output directory (parameter 2).
+// Credits to https://golangcode.com/unzip-files-in-go/
+func Unzip(src string, dest string) ([]string, error) {
+	var filenames []string
+
+	r, err := zip.OpenReader(src)
+	if err != nil {
+		return filenames, err
+	}
+	defer r.Close()
+
+	for _, f := range r.File {
+		rc, err := f.Open()
+		if err != nil {
+			return filenames, err
+		}
+		defer rc.Close()
+
+		// Store filename/path for returning and using later on
+		fpath := filepath.Join(dest, f.Name)
+
+		// Check for ZipSlip. More Info: https://snyk.io/research/zip-slip-vulnerability#go
+		if !strings.HasPrefix(fpath, filepath.Clean(dest)+string(os.PathSeparator)) {
+			return filenames, fmt.Errorf("%s: illegal file path", fpath)
+		}
+
+		filenames = append(filenames, fpath)
+		if f.FileInfo().IsDir() {
+			os.MkdirAll(fpath, os.ModePerm)
+		} else if err = os.MkdirAll(filepath.Dir(fpath), os.ModePerm); err != nil {
+			return filenames, err
+		} else if outFile, err := os.OpenFile(fpath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode()); err != nil {
+			return filenames, err
+		} else {
+			defer outFile.Close()
+			if _, err = io.Copy(outFile, rc); err != nil {
+				return filenames, err
+			}
+		}
+	}
+
+	return filenames, nil
+}