Merge pull request #193 from wneessen/implement_fuzzing

Implement fuzzing

.gitignore

@@ -55,3 +55,5 @@ com_crashlytics_export_strings.xml
 crashlytics.properties
 crashlytics-build.properties
 fabric.properties
+
+testdata

b64linebreaker_test.go

@@ -5,6 +5,7 @@
 package mail
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/base64"
 	"fmt"
@@ -461,3 +462,20 @@ func (e errorWriter) Write([]byte) (int, error) {
 func (e errorWriter) Close() error {
 	return fmt.Errorf("supposed to always fail")
 }
+
+func FuzzBase64LineBreaker_Write(f *testing.F) {
+	f.Add([]byte("abc"))
+	f.Add([]byte("def"))
+	f.Add([]uint8{0o0, 0o1, 0o2, 30, 255})
+	buf := bytes.Buffer{}
+	bw := bufio.NewWriter(&buf)
+	f.Fuzz(func(t *testing.T, data []byte) {
+		b := &Base64LineBreaker{out: bw}
+		if _, err := b.Write(data); err != nil {
+			t.Errorf("failed to write to B64LineBreaker: %s", err)
+		}
+		if err := b.Close(); err != nil {
+			t.Errorf("failed to close B64LineBreaker: %s", err)
+		}
+	})
+}

msg_test.go

@@ -3219,3 +3219,31 @@ func TestNewMsgWithNoDefaultUserAgent(t *testing.T) {
 		t.Errorf("WithNoDefaultUserAgent() failed. Expected: %t, got: %t", true, false)
 	}
 }
+
+// Fuzzing tests
+func FuzzMsg_Subject(f *testing.F) {
+	f.Add("Testsubject")
+	f.Add("")
+	f.Add("This is a longer test subject.")
+	f.Add("Let's add some umlauts: üäöß")
+	f.Add("Or even emojis: ☝️💪👍")
+	f.Fuzz(func(t *testing.T, data string) {
+		m := NewMsg()
+		m.Subject(data)
+		m.Reset()
+	})
+}
+
+func FuzzMsg_From(f *testing.F) {
+	f.Add("Toni Tester <toni@tester.com>")
+	f.Add("<tester@example.com>")
+	f.Add("mail@server.com")
+	f.Fuzz(func(t *testing.T, data string) {
+		m := NewMsg()
+		if err := m.From(data); err != nil &&
+			!strings.Contains(err.Error(), "failed to parse mail address") {
+			t.Errorf("failed set set FROM address: %s", err)
+		}
+		m.Reset()
+	})
+}