/*
 * netsniff-ng - the packet sniffing beast
 * Copyright 2009, 2010 Daniel Borkmann.
 * Copyright 2014 Tobias Klauser
 * Subject to the GPL, version 2.
 */

#include <stdio.h>
#include <stdint.h>
#include <netinet/in.h>
#include <linux/if_ether.h>

#include "proto.h"
#include "dissector_eth.h"
#include "lookup.h"
#include "pkt_buff.h"

static inline bool is_multicast_ether_addr(const uint8_t *mac)
{
	return mac[0] & 0x01;
}

static inline bool is_broadcast_ether_addr(const uint8_t *mac)
{
	return (mac[0] & mac[1] & mac[2] & mac[3] & mac[4] & mac[5]) == 0xff;
}

static inline bool is_local_ether_addr(const u8 *mac)
{
	return 0x02 & mac[0];
}

static const char *ether_lookup_addr(const uint8_t *mac)
{
	if (is_multicast_ether_addr(mac)) {
		if (is_broadcast_ether_addr(mac))
			return "Broadcast";
		else
			return "Multicast";
	} else if (is_local_ether_addr(mac)) {
		return "Locally Administered";
	}

	/* found no matching address, so look up the vendor from OUI */
	return lookup_vendor_str((mac[0] << 16) | (mac[1] << 8) | mac[2]);
}

static void ethernet(struct pkt_buff *pkt)
{
	const char *type;
	uint8_t *src_mac, *dst_mac;
	struct ethhdr *eth = (struct ethhdr *) pkt_pull(pkt, sizeof(*eth));

	if (eth == NULL)
		return;

	src_mac = eth->h_source;
	dst_mac = eth->h_dest;

	tprintf(" [ Eth ");
	tprintf("MAC (%.2x:%.2x:%.2x:%.2x:%.2x:%.2x => ",
		src_mac[0], src_mac[1], src_mac[2],
		src_mac[3], src_mac[4], src_mac[5]);
	tprintf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x), ",
		dst_mac[0], dst_mac[1], dst_mac[2],
		dst_mac[3], dst_mac[4], dst_mac[5]);
	tprintf("Proto (0x%.4x", ntohs(eth->h_proto));

	type = lookup_ether_type(ntohs(eth->h_proto));
	if (type)
		tprintf(", %s%s%s", colorize_start(bold), type, colorize_end());

	tprintf(") ]\n");
	tprintf(" [ Vendor ");
	tprintf("(%s => %s)", ether_lookup_addr(src_mac), ether_lookup_addr(dst_mac));
	tprintf(" ]\n");

	pkt_set_dissector(pkt, &eth_lay2, ntohs(eth->h_proto));
}

static void ethernet_less(struct pkt_buff *pkt)
{
	uint8_t *src_mac, *dst_mac;
	struct ethhdr *eth = (struct ethhdr *) pkt_pull(pkt, sizeof(*eth));

	if (eth == NULL)
		return;

	src_mac = eth->h_source;
	dst_mac = eth->h_dest;
	tprintf(" %s => %s ", ether_lookup_addr(src_mac),
		ether_lookup_addr(dst_mac));
	tprintf("%s%s%s", colorize_start(bold),
		lookup_ether_type(ntohs(eth->h_proto)), colorize_end());

	pkt_set_dissector(pkt, &eth_lay2, ntohs(eth->h_proto));
}

struct protocol ethernet_ops = {
	.key = 0,
	.print_full = ethernet,
	.print_less = ethernet_less,
};