first commit

internal/pathutils/clean.go

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+/*
+© Copyright IBM Corporation 2023
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package pathutils contains code to provide sanitised file paths
+package pathutils
+
+import (
+	"path"
+	"path/filepath"
+)
+
+// CleanPath returns the result of joining a series of sanitised file paths (preventing directory traversal for each path)
+// If the first path is relative, a relative path is returned
+func CleanPath(paths ...string) string {
+	if len(paths) == 0 {
+		return ""
+	}
+	var combined string
+	if !path.IsAbs(paths[0]) {
+		combined = "./"
+	}
+	for _, part := range paths {
+		combined = filepath.Join(combined, filepath.FromSlash(path.Clean("/"+part)))
+	}
+	return combined
+}

internal/pathutils/clean_test.go

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+/*
+© Copyright IBM Corporation 2023
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package pathutils
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestClean(t *testing.T) {
+
+	tests := []struct {
+		uncleaned string
+		filepath      string
+		cleaned   string
+	}{
+		{"/a/rooted/path", "some.file", "/a/rooted/path/some.file"},
+		{"../../../a/relative/path", "abc.txt", "a/relative/path/abc.txt"},
+		{"a/path" + ".p12", "some.file", "a/path.p12/some.file"},
+		{"/", "bin", "/bin"},
+		{"abc/def", "../../a/relative/path", "abc/def/a/relative/path"},
+	}
+
+	for _, test := range tests {
+		cleaned := CleanPath(test.uncleaned, test.filepath)
+
+		if !strings.EqualFold(cleaned, test.cleaned) {
+			t.Fatalf("file path sanitisation failed. Expected %s but got %s\n", test.cleaned, cleaned)
+		}
+	}
+}