helper/salt: track if salt was generated

helper/salt/salt.go

@@ -21,8 +21,9 @@ const (
 // using the global salt. Primarily, this allows paths in the storage
 // backend to be obfuscated if they may contain sensitive information.
 type Salt struct {
-	config *Config
-	salt   string
+	config    *Config
+	salt      string
+	generated bool
 }
 
 type HashFunc func([]byte) []byte
@@ -70,6 +71,7 @@ func NewSalt(view logical.Storage, config *Config) (*Salt, error) {
 	// Generate a new salt if necessary
 	if s.salt == "" {
 		s.salt = uuid.GenerateUUID()
+		s.generated = true
 		raw = &logical.StorageEntry{
 			Key:   config.Location,
 			Value: []byte(s.salt),
@@ -87,6 +89,12 @@ func (s *Salt) SaltID(id string) string {
 	return SaltID(s.salt, id, s.config.HashFunc)
 }
 
+// DidGenerate returns if the underlying salt value was generated
+// on initialization or if an existing salt value was loaded
+func (s *Salt) DidGenerate() bool {
+	return s.generated
+}
+
 // SaltID is used to apply a salt and hash functio to an ID to make sure
 // it is not reversable
 func SaltID(salt, id string, hash HashFunc) string {

helper/salt/salt_test.go

@@ -18,6 +18,10 @@ func TestSalt(t *testing.T) {
 		t.Fatalf("err: %v", err)
 	}
 
+	if !salt.DidGenerate() {
+		t.Fatalf("expected generation")
+	}
+
 	// Verify the salt exists
 	out, err := inm.Get(DefaultLocation)
 	if err != nil {
@@ -33,6 +37,10 @@ func TestSalt(t *testing.T) {
 		t.Fatalf("err: %v", err)
 	}
 
+	if salt2.DidGenerate() {
+		t.Fatalf("unexpected generation")
+	}
+
 	// Check for a match
 	if salt.salt != salt2.salt {
 		t.Fatalf("salt mismatch: %s %s", salt.salt, salt2.salt)