// SPDX-License-Identifier: GPL-2.0-or-later

/* PASST - Plug A Simple Socket Transport
 *  for qemu/UNIX domain socket mode
 *
 * PASTA - Pack A Subtle Tap Abstraction
 *  for network namespace/tap device mode
 *
 * PESTO - Programmable Extensible Socket Translation Orchestrator
 *  front-end for passt(1) and pasta(1) forwarding configuration
 *
 * fwd_rule.c - Helpers for working with forwarding rule specifications
 *
 * Copyright Red Hat
 * Author: David Gibson <david@gibson.dropbear.id.au>
 */

#include <stdio.h>

#include "fwd_rule.h"

/**
 * fwd_rule_addr() - Return match address for a rule
 * @rule:	Forwarding rule
 *
 * Return: matching address for rule, NULL if it matches all addresses
 */
const union inany_addr *fwd_rule_addr(const struct fwd_rule *rule)
{
	if (rule->flags & FWD_DUAL_STACK_ANY)
		return NULL;

	return &rule->addr;
}

/**
 * fwd_rule_ntop() - Format forwarding rule as a string
 * @rule:	Rule to format
 * @dst:	Buffer to store output (should have FWD_RULE_STRLEN bytes)
 * @size:	Size of @dst
 */
const char *fwd_rule_ntop(const struct fwd_rule *rule, char *dst, size_t size)
{
	const char *percent = *rule->ifname ? "%" : "";
	const char *weak = "", *scan = "";
	char addr[INANY_ADDRSTRLEN];
	int len;

	inany_ntop(fwd_rule_addr(rule), addr, sizeof(addr));
	if (rule->flags & FWD_WEAK)
		weak = " (best effort)";
	if (rule->flags & FWD_SCAN)
		scan = " (auto-scan)";

	if (rule->first == rule->last) {
		len = snprintf(dst, size,
			       "%s [%s]%s%s:%hu  =>  %hu %s%s",
			       ipproto_name(rule->proto), addr, percent,
			       rule->ifname, rule->first, rule->to, weak, scan);
	} else {
		in_port_t tolast = rule->last - rule->first + rule->to;
		len = snprintf(dst, size,
			       "%s [%s]%s%s:%hu-%hu  =>  %hu-%hu %s%s",
			       ipproto_name(rule->proto), addr, percent,
			       rule->ifname, rule->first, rule->last,
			       rule->to, tolast, weak, scan);
	}

	if (len < 0 || (size_t)len >= size)
		return NULL;

	return dst;
}