/* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */

#include "auth-common.h"
#include "passdb.h"
#include "passdb-template.h"
#include "password-scheme.h"

struct static_passdb_module {
	struct passdb_module module;
	struct passdb_template *tmpl;
	const char *static_password_tmpl;
};

static enum passdb_result
static_save_fields(struct auth_request *request, const char **password_r,
		   const char **scheme_r)
{
	struct static_passdb_module *module =
		(struct static_passdb_module *)request->passdb->passdb;
	const char *error;

	*password_r = NULL;
	*scheme_r = NULL;

	e_debug(authdb_event(request), "lookup");
	if (passdb_template_export(module->tmpl, request, &error) < 0) {
		e_error(authdb_event(request),
			"Failed to expand template: %s", error);
		return PASSDB_RESULT_INTERNAL_FAILURE;
	}

	if (module->static_password_tmpl != NULL) {
		if (t_auth_request_var_expand(module->static_password_tmpl,
				request, NULL, password_r, &error) <= 0) {
			e_error(authdb_event(request),
				"Failed to expand password=%s: %s",
				module->static_password_tmpl, error);
			return PASSDB_RESULT_INTERNAL_FAILURE;
		}
	} else if (auth_fields_exists(request->fields.extra_fields, "nopassword")) {
		*password_r = "";
	} else {
		return auth_request_password_missing(request);
	}

	*scheme_r = password_get_scheme(password_r);

	if (*scheme_r == NULL)
		*scheme_r = STATIC_PASS_SCHEME;

	auth_request_set_field(request, "password",
			       *password_r, *scheme_r);

	return PASSDB_RESULT_OK;
}

static void
static_verify_plain(struct auth_request *request, const char *password,
		    verify_plain_callback_t *callback)
{
	enum passdb_result result;
	const char *static_password;
	const char *static_scheme;

	result = static_save_fields(request, &static_password, &static_scheme);
	if (result != PASSDB_RESULT_OK) {
		callback(result, request);
		return;
	}

	result = auth_request_password_verify(request, password, static_password,
					      static_scheme, AUTH_SUBSYS_DB);
	callback(result, request);
}

static void
static_lookup_credentials(struct auth_request *request,
			  lookup_credentials_callback_t *callback)
{
	enum passdb_result result;
	const char *static_password;
	const char *static_scheme;

	result = static_save_fields(request, &static_password, &static_scheme);
	passdb_handle_credentials(result, static_password,
				  static_scheme, callback, request);
}

static struct passdb_module *
static_preinit(pool_t pool, const char *args)
{
	struct static_passdb_module *module;
	const char *value;

	module = p_new(pool, struct static_passdb_module, 1);
	module->tmpl = passdb_template_build(pool, args);

	if (passdb_template_remove(module->tmpl, "password", &value))
		module->static_password_tmpl = value;
	return &module->module;
}

struct passdb_module_interface passdb_static = {
	"static",

	static_preinit,
	NULL,
	NULL,

	static_verify_plain,
	static_lookup_credentials,
	NULL
};
