Add crypt_get_default_type() API call.

lib/libcryptsetup.h

@@ -424,6 +424,13 @@ int crypt_get_metadata_size(struct crypt_device *cd,
  */
 const char *crypt_get_type(struct crypt_device *cd);
 
+/**
+ * Get device default LUKS type
+ *
+ * @return string according to device type (CRYPT_LUKS1 or CRYPT_LUKS2).
+ */
+const char *crypt_get_default_type(void);
+
 /**
  *
  * Structure used as parameter for PLAIN device type.

lib/libcryptsetup.sym

@@ -81,6 +81,7 @@ CRYPTSETUP_2.0 {
 		crypt_get_sector_size;
 
 		crypt_get_type;
+		crypt_get_default_type;
 		crypt_get_active_device;
 		crypt_get_active_integrity_failures;
 		crypt_persistent_flags_set;

lib/setup.c

@@ -4810,6 +4810,11 @@ const char *crypt_get_type(struct crypt_device *cd)
 	return cd ? cd->type : NULL;
 }
 
+const char *crypt_get_default_type(void)
+{
+	return DEFAULT_LUKS_FORMAT;
+}
+
 int crypt_get_verity_info(struct crypt_device *cd,
 	struct crypt_params_verity *vp)
 {

src/cryptsetup.c

@@ -1038,7 +1038,7 @@ static int action_luksFormat(void)
 
 	type = luksType(opt_type);
 	if (!type)
-		type = DEFAULT_LUKS_FORMAT;
+		type = crypt_get_default_type();
 
 	if (!strcmp(type, CRYPT_LUKS2)) {
 		params = &params2;
@@ -2418,7 +2418,7 @@ static void help(poptContext popt_context,
 			crypt_get_dir());
 
 		log_std(_("\nDefault compiled-in metadata format is %s (for luksFormat action).\n"),
-			  DEFAULT_LUKS_FORMAT);
+			  crypt_get_default_type());
 
 		pbkdf_luks1 = crypt_get_pbkdf_default(CRYPT_LUKS1);
 		pbkdf_luks2 = crypt_get_pbkdf_default(CRYPT_LUKS2);

src/cryptsetup_reencrypt.c

@@ -148,7 +148,7 @@ static const char *luksType(const char *type)
 		return CRYPT_LUKS1;
 
 	if (!type || !strcmp(type, "luks"))
-		return DEFAULT_LUKS_FORMAT;
+		return crypt_get_default_type();
 
 	return NULL;
 }