/* main.c - Application main entry point */

/*
 * Copyright (c) 2016 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(net_test, CONFIG_NET_DHCPV4_LOG_LEVEL);

#include <zephyr/kernel.h>
#include <zephyr/linker/sections.h>

#include <zephyr/types.h>
#include <stddef.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <zephyr/device.h>
#include <zephyr/init.h>
#include <zephyr/net/net_core.h>
#include <zephyr/net/net_pkt.h>
#include <zephyr/net/net_ip.h>
#include <zephyr/net/dhcpv4.h>
#include <zephyr/net/ethernet.h>
#include <zephyr/net/net_mgmt.h>
#include <zephyr/net/dummy.h>

#include "ipv4.h"
#include "udp_internal.h"

#include <zephyr/tc_util.h>
#include <zephyr/ztest.h>

#define NET_LOG_ENABLED 1
#include "net_private.h"

/* Sample DHCP offer (420 bytes) */
static const unsigned char offer[420] = {
0x02, 0x01, 0x06, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x0a, 0xed, 0x48, 0x9e, 0x0a, 0xb8,
0x09, 0x01, 0x0a, 0xed, 0x48, 0x02, 0x00, 0x00,
0x5E, 0x00, 0x53, 0x01, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
/* Magic cookie: DHCP */
0x63, 0x82, 0x53, 0x63,
/* [53] DHCP Message Type: OFFER */
0x35, 0x01, 0x02,
/* [1] Subnet Mask: 255.255.255.0 */
0x01, 0x04, 0xff, 0xff, 0xff, 0x00,
/* [58] Renewal Time Value: (21600s) 6 hours */
0x3a, 0x04, 0x00, 0x00, 0x54, 0x60,
/* [59] Rebinding Time Value: (37800s) 1 hour 30 min */
0x3b, 0x04, 0x00, 0x00, 0x93, 0xa8,
/* [51] IP Address Lease Time: (43200s) 12 hours */
0x33, 0x04, 0x00, 0x00, 0xa8, 0xc0,
/* [54] DHCP Server Identifier: 10.184.9.1 */
0x36, 0x04, 0x0a, 0xb8, 0x09, 0x01,
/* [3] Router: 10.237.72.1 */
0x03, 0x04, 0x0a, 0xed, 0x48, 0x01,
/* [15] Domain Name: fi.intel.com */
0x0f, 0x0d, 0x66, 0x69, 0x2e, 0x69, 0x6e, 0x74, 0x65, 0x6c, 0x2e, 0x63, 0x6f, 0x6d, 0x00,
/* [6] Domain Name Server: 10.248.2.1 163.33.253.68 10.184.9.1 */
0x06, 0x0c, 0x0a, 0xf8, 0x02, 0x01, 0xa3, 0x21, 0xfd, 0x44, 0x0a, 0xb8, 0x09, 0x01,
/* [119] Domain Search Option: fi.intel.com ger.corp.intel.com corp.intel.com intel.com */
0x77, 0x3d, 0x02, 0x66, 0x69, 0x05, 0x69, 0x6e,
0x74, 0x65, 0x6c, 0x03, 0x63, 0x6f, 0x6d, 0x00,
0x03, 0x67, 0x65, 0x72, 0x04, 0x63, 0x6f, 0x72,
0x70, 0x05, 0x69, 0x6e, 0x74, 0x65, 0x6c, 0x03,
0x63, 0x6f, 0x6d, 0x00, 0x04, 0x63, 0x6f, 0x72,
0x70, 0x05, 0x69, 0x6e, 0x74, 0x65, 0x6c, 0x03,
0x63, 0x6f, 0x6d, 0x00, 0x05, 0x69, 0x6e, 0x74,
0x65, 0x6c, 0x03, 0x63, 0x6f, 0x6d, 0x00,
/* [44] NetBIOS Name Servers: 163.33.7.86, 143.182.250.105 */
0x2c, 0x08, 0xa3, 0x21, 0x07, 0x56, 0x8f, 0xb6, 0xfa, 0x69,
/* [43] Encapsulated vendor specific information */
0x2b, 0x0a,
	    /* [1]: "string" */
	    0x01, 0x07, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x00,
	    /* End marker */
	    0xff,
/* [43] Encapsulated vendor specific information */
0x2b, 0x0f,
	    /* [2]: single byte of value 1 */
	    0x02, 0x01, 0x01,
	    /* [3]: zero-length option */
	    0x03, 0x00,
	    /* [254]: invalid option (size longer than remainder of opt 43 size) */
	    0xfe, 0x10, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe,
/* [43] Too short encapsulated vendor option (only single byte) */
0x2b, 0x01,
	    /* [254]: invalid option (no length in opt 43) */
	    0xfe,
/* [70] POP3 Server: 198.51.100.16 */
0x46, 0x04, 0xc6, 0x33, 0x64, 0x10,
/* End marker */
0xff
};

/* Sample DHCPv4 ACK */
static const unsigned char ack[420] = {
0x02, 0x01, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x0a, 0xed, 0x48, 0x9e, 0x00, 0x00, 0x00, 0x00,
0x0a, 0xed, 0x48, 0x03, 0x00, 0x00, 0x5E, 0x00,
0x53, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
/* Magic cookie: DHCP */
0x63, 0x82, 0x53, 0x63,
/* [53] DHCP Message Type: ACK */
0x35, 0x01, 0x05,
/* [58] Renewal Time Value: (21600s) 6 hours */
0x3a, 0x04, 0x00, 0x00, 0x54, 0x60,
/* [59] Rebinding Time Value: (37800s) 1 hour 30 min */
0x3b, 0x04, 0x00, 0x00, 0x93, 0xa8,
/* [51] IP Address Lease Time: (43200s) 12 hours */
0x33, 0x04, 0x00, 0x00, 0xa8, 0xc0,
/* [54] DHCP Server Identifier: 10.184.9.1 */
0x36, 0x04, 0x0a, 0xb8, 0x09, 0x01,
/* [1] Subnet Mask: 255.255.255.0 */
0x01, 0x04, 0xff, 0xff, 0xff, 0x00,
/* [3] Router: 10.237.72.1 */
0x03, 0x04, 0x0a, 0xed, 0x48, 0x01,
/* [15] Domain Name: fi.intel.com */
0x0f, 0x0d, 0x66, 0x69, 0x2e, 0x69, 0x6e, 0x74, 0x65, 0x6c, 0x2e, 0x63, 0x6f, 0x6d, 0x00,
/* [6] Domain Name Server: 10.248.2.1 163.33.253.68 10.184.9.1 */
0x06, 0x0c, 0x0a, 0xf8, 0x02, 0x01, 0xa3, 0x21, 0xfd, 0x44, 0x0a, 0xb8, 0x09, 0x01,
/* [119] Domain Search Option: fi.intel.com ger.corp.intel.com corp.intel.com intel.com */
0x77, 0x3d, 0x02, 0x66, 0x69, 0x05, 0x69, 0x6e,
0x74, 0x65, 0x6c, 0x03, 0x63, 0x6f, 0x6d, 0x00,
0x03, 0x67, 0x65, 0x72, 0x04, 0x63, 0x6f, 0x72,
0x70, 0x05, 0x69, 0x6e, 0x74, 0x65, 0x6c, 0x03,
0x63, 0x6f, 0x6d, 0x00, 0x04, 0x63, 0x6f, 0x72,
0x70, 0x05, 0x69, 0x6e, 0x74, 0x65, 0x6c, 0x03,
0x63, 0x6f, 0x6d, 0x00, 0x05, 0x69, 0x6e, 0x74,
0x65, 0x6c, 0x03, 0x63, 0x6f, 0x6d, 0x00,
/* [44] NetBIOS Name Servers: 163.33.7.86, 143.182.250.105 */
0x2c, 0x08, 0xa3, 0x21, 0x07, 0x56, 0x8f, 0xb6, 0xfa, 0x69,
/* [43] Encapsulated vendor specific information */
0x2b, 0x0a,
	    /* [1]: "string" */
	    0x01, 0x07, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x00,
	    /* End marker */
	    0xff,
/* [43] Encapsulated vendor specific information */
0x2b, 0x0f,
	    /* [2]: single byte of value 1 */
	    0x02, 0x01, 0x01,
	    /* [3]: zero-length option */
	    0x03, 0x00,
	    /* [254]: invalid option (size longer than remainder of opt 43 size) */
	    0xfe, 0x10, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe,
/* [43] Too short encapsulated vendor option (only single byte) */
0x2b, 0x01,
	    /* [254]: invalid option (no length in opt 43) */
	    0xfe,
/* [70] POP3 Server: 198.51.100.16 */
0x46, 0x04, 0xc6, 0x33, 0x64, 0x10,
/* End marker */
0xff
};

static const struct in_addr server_addr = { { { 192, 0, 2, 1 } } };
static const struct in_addr client_addr = { { { 255, 255, 255, 255 } } };

#define SERVER_PORT		67
#define CLIENT_PORT		68
#define MSG_TYPE		53
#define DISCOVER		1
#define REQUEST			3
#define OPTION_DOMAIN		15
#define OPTION_POP3		70
#define OPTION_VENDOR_STRING	1
#define OPTION_VENDOR_BYTE	2
#define OPTION_VENDOR_EMPTY	3
#define OPTION_INVALID		254

struct dhcp_msg {
	uint32_t xid;
	uint8_t type;
};

static struct k_sem test_lock;

#define WAIT_TIME K_SECONDS(CONFIG_NET_DHCPV4_INITIAL_DELAY_MAX + 1)

struct net_dhcpv4_context {
	uint8_t mac_addr[sizeof(struct net_eth_addr)];
	struct net_linkaddr ll_addr;
};

static int net_dhcpv4_dev_init(const struct device *dev)
{
	struct net_dhcpv4_context *net_dhcpv4_context = dev->data;

	net_dhcpv4_context = net_dhcpv4_context;

	return 0;
}

static uint8_t *net_dhcpv4_get_mac(const struct device *dev)
{
	struct net_dhcpv4_context *context = dev->data;

	if (context->mac_addr[2] == 0x00) {
		/* 00-00-5E-00-53-xx Documentation RFC 7042 */
		context->mac_addr[0] = 0x00;
		context->mac_addr[1] = 0x00;
		context->mac_addr[2] = 0x5E;
		context->mac_addr[3] = 0x00;
		context->mac_addr[4] = 0x53;
		context->mac_addr[5] = 0x01;
	}

	return context->mac_addr;
}

static void net_dhcpv4_iface_init(struct net_if *iface)
{
	uint8_t *mac = net_dhcpv4_get_mac(net_if_get_device(iface));

	net_if_set_link_addr(iface, mac, 6, NET_LINK_ETHERNET);
}

struct net_pkt *prepare_dhcp_offer(struct net_if *iface, uint32_t xid)
{
	struct net_pkt *pkt;

	pkt = net_pkt_alloc_with_buffer(iface, sizeof(offer), AF_INET,
					IPPROTO_UDP, K_FOREVER);
	if (!pkt) {
		return NULL;
	}

	net_pkt_set_ipv4_ttl(pkt, 0xFF);

	if (net_ipv4_create(pkt, &server_addr, &client_addr) ||
	    net_udp_create(pkt, htons(SERVER_PORT), htons(CLIENT_PORT))) {
		goto fail;
	}

	if (net_pkt_write(pkt, offer, 4)) {
		goto fail;
	}

	/* Update xid from the client request */
	if (net_pkt_write_be32(pkt, xid)) {
		goto fail;
	}

	if (net_pkt_write(pkt, offer + 8, sizeof(offer) - 8)) {
		goto fail;
	}

	net_pkt_cursor_init(pkt);

	net_ipv4_finalize(pkt, IPPROTO_UDP);

	return pkt;

fail:
	net_pkt_unref(pkt);
	return NULL;
}

struct net_pkt *prepare_dhcp_ack(struct net_if *iface, uint32_t xid)
{
	struct net_pkt *pkt;

	pkt = net_pkt_alloc_with_buffer(iface, sizeof(offer), AF_INET,
					IPPROTO_UDP, K_FOREVER);
	if (!pkt) {
		return NULL;
	}

	net_pkt_set_ipv4_ttl(pkt, 0xFF);

	if (net_ipv4_create(pkt, &server_addr, &client_addr) ||
	    net_udp_create(pkt, htons(SERVER_PORT), htons(CLIENT_PORT))) {
		goto fail;
	}

	if (net_pkt_write(pkt, ack, 4)) {
		goto fail;
	}

	/* Update xid from the client request */
	if (net_pkt_write_be32(pkt, xid)) {
		goto fail;
	}

	if (net_pkt_write(pkt, ack + 8, sizeof(ack) - 8)) {
		goto fail;
	}

	net_pkt_cursor_init(pkt);

	net_ipv4_finalize(pkt, IPPROTO_UDP);

	return pkt;

fail:
	net_pkt_unref(pkt);
	return NULL;
}

static int parse_dhcp_message(struct net_pkt *pkt, struct dhcp_msg *msg)
{
	/* Skip IPv4 and UDP headers */
	if (net_pkt_skip(pkt, NET_IPV4UDPH_LEN)) {
		return 0;
	}

	/* Skip DHCPv4 headers (size of op, htype, hlen, hops) */
	if (net_pkt_skip(pkt, 4)) {
		return 0;
	}

	if (net_pkt_read_be32(pkt, &msg->xid)) {
		return 0;
	}

	/* Skip DHCPv4 Options (size of op, htype, ... cookie) */
	if (net_pkt_skip(pkt, 36 + 64 + 128 + 4)) {
		return 0;
	}

	while (1) {
		uint8_t length = 0U;
		uint8_t type;

		if (net_pkt_read_u8(pkt, &type)) {
			return 0;
		}

		if (type == MSG_TYPE) {
			if (net_pkt_skip(pkt, 1)) {
				return 0;
			}

			if (net_pkt_read_u8(pkt, &msg->type)) {
				return 0;
			}

			return 1;
		}

		if (net_pkt_read_u8(pkt, &length)) {
			return 0;
		}

		if (length && net_pkt_skip(pkt, length)) {
			return 0;
		}
	}

	return 0;
}

static int tester_send(const struct device *dev, struct net_pkt *pkt)
{
	struct net_pkt *rpkt;
	struct dhcp_msg msg;

	(void)memset(&msg, 0, sizeof(msg));

	if (!pkt->frags) {
		TC_PRINT("No data to send!\n");

		return -ENODATA;
	}

	parse_dhcp_message(pkt, &msg);

	if (msg.type == DISCOVER) {
		/* Reply with DHCPv4 offer message */
		rpkt = prepare_dhcp_offer(net_pkt_iface(pkt), msg.xid);
		if (!rpkt) {
			return -EINVAL;
		}
	} else if (msg.type == REQUEST) {
		/* Reply with DHCPv4 ACK message */
		rpkt = prepare_dhcp_ack(net_pkt_iface(pkt), msg.xid);
		if (!rpkt) {
			return -EINVAL;
		}
	} else {
		/* Invalid message type received */
		return -EINVAL;
	}

	if (net_recv_data(net_pkt_iface(rpkt), rpkt)) {
		net_pkt_unref(rpkt);

		return -EINVAL;
	}

	return 0;
}

struct net_dhcpv4_context net_dhcpv4_context_data;

static struct dummy_api net_dhcpv4_if_api = {
	.iface_api.init = net_dhcpv4_iface_init,
	.send = tester_send,
};

NET_DEVICE_INIT(net_dhcpv4_test, "net_dhcpv4_test",
		net_dhcpv4_dev_init, NULL,
		&net_dhcpv4_context_data, NULL,
		CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
		&net_dhcpv4_if_api, DUMMY_L2,
		NET_L2_GET_CTX_TYPE(DUMMY_L2), 127);

static struct net_mgmt_event_callback rx_cb;
static struct net_mgmt_event_callback dns_cb;
static struct net_mgmt_event_callback dhcp_cb;
#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS
static struct net_dhcpv4_option_callback opt_domain_cb;
static struct net_dhcpv4_option_callback opt_pop3_cb;
static struct net_dhcpv4_option_callback opt_invalid_cb;
static uint8_t buffer[15];
#endif
#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS_VENDOR_SPECIFIC
static struct net_dhcpv4_option_callback opt_vs_string_cb;
static struct net_dhcpv4_option_callback opt_vs_byte_cb;
static struct net_dhcpv4_option_callback opt_vs_empty_cb;
static struct net_dhcpv4_option_callback opt_vs_invalid_cb;
#endif
static int event_count;

static void receiver_cb(struct net_mgmt_event_callback *cb,
			uint32_t nm_event, struct net_if *iface)
{
	if (nm_event != NET_EVENT_IPV4_ADDR_ADD &&
	    nm_event != NET_EVENT_DNS_SERVER_ADD &&
	    nm_event != NET_EVENT_DNS_SERVER_DEL &&
	    nm_event != NET_EVENT_IPV4_DHCP_START &&
	    nm_event != NET_EVENT_IPV4_DHCP_BOUND) {
		/* Spurious callback. */
		return;
	}

	event_count++;

	k_sem_give(&test_lock);
}

#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS

static void option_domain_cb(struct net_dhcpv4_option_callback *cb,
			     size_t length,
			     enum net_dhcpv4_msg_type msg_type,
			     struct net_if *iface)
{
	char expectation[] = "fi.intel.com";

	zassert_equal(cb->option, OPTION_DOMAIN, "Unexpected option value");
	zassert_equal(length, sizeof(expectation), "Incorrect data length");
	zassert_mem_equal(buffer, expectation, sizeof(expectation),
			  "Incorrect buffer contents");

	event_count++;

	k_sem_give(&test_lock);
}

static void option_pop3_cb(struct net_dhcpv4_option_callback *cb,
			   size_t length,
			   enum net_dhcpv4_msg_type msg_type,
			   struct net_if *iface)
{
	uint8_t expectation[4];

	expectation[0] = 198;
	expectation[1] = 51;
	expectation[2] = 100;
	expectation[3] = 16;

	zassert_equal(cb->option, OPTION_POP3, "Unexpected option value");
	zassert_equal(length, sizeof(expectation), "Incorrect data length");
	zassert_mem_equal(buffer, expectation, sizeof(expectation),
			  "Incorrect buffer contents");

	event_count++;

	k_sem_give(&test_lock);
}

static void option_invalid_cb(struct net_dhcpv4_option_callback *cb,
			      size_t length,
			      enum net_dhcpv4_msg_type msg_type,
			      struct net_if *iface)
{
	/* This function should never be called. If it is, the parser took a wrong turn. */
	zassert_true(false, "Unexpected callback - incorrect parsing of vendor sepcific options");
}

#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS_VENDOR_SPECIFIC

static void vendor_specific_string_cb(struct net_dhcpv4_option_callback *cb,
				      size_t length,
				      enum net_dhcpv4_msg_type msg_type,
				      struct net_if *iface)
{
	char expectation[] = "string";

	zassert_equal(cb->option, OPTION_VENDOR_STRING,
		      "Unexpected vendor specific option value");
	zassert_equal(length, sizeof(expectation), "Incorrect data length");
	zassert_mem_equal(buffer, expectation, sizeof(expectation), "Incorrect buffer contents");

	event_count++;

	k_sem_give(&test_lock);
}

static void vendor_specific_byte_cb(struct net_dhcpv4_option_callback *cb,
				    size_t length,
				    enum net_dhcpv4_msg_type msg_type,
				    struct net_if *iface)
{
	zassert_equal(cb->option, OPTION_VENDOR_BYTE,
		      "Unexpected vendor specific option value");
	zassert_equal(length, 1, "Incorrect data length");
	zassert_equal(buffer[0], 1, "Incorrect buffer contents");

	event_count++;

	k_sem_give(&test_lock);
}

static void vendor_specific_empty_cb(struct net_dhcpv4_option_callback *cb,
				     size_t length,
				     enum net_dhcpv4_msg_type msg_type,
				     struct net_if *iface)
{
	zassert_equal(cb->option, OPTION_VENDOR_EMPTY,
		      "Unexpected vendor specific option value");
	zassert_equal(length, 0, "Incorrect data length");

	event_count++;

	k_sem_give(&test_lock);
}

#endif /* CONFIG_NET_DHCPV4_OPTION_CALLBACKS_VENDOR_SPECIFIC */

#endif /* CONFIG_NET_DHCPV4_OPTION_CALLBACKS */

ZTEST(dhcpv4_tests, test_dhcp)
{
	struct net_if *iface;

	k_sem_init(&test_lock, 0, UINT_MAX);

	net_mgmt_init_event_callback(&rx_cb, receiver_cb,
				     NET_EVENT_IPV4_ADDR_ADD);

	net_mgmt_add_event_callback(&rx_cb);

	net_mgmt_init_event_callback(&dns_cb, receiver_cb,
				     NET_EVENT_DNS_SERVER_ADD |
				     NET_EVENT_DNS_SERVER_DEL);

	net_mgmt_add_event_callback(&dns_cb);

	net_mgmt_init_event_callback(&dhcp_cb, receiver_cb,
				     NET_EVENT_IPV4_DHCP_START |
				     NET_EVENT_IPV4_DHCP_BOUND);

	net_mgmt_add_event_callback(&dhcp_cb);

#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS
	net_dhcpv4_init_option_callback(&opt_domain_cb, option_domain_cb,
					OPTION_DOMAIN, buffer,
					sizeof(buffer));

	net_dhcpv4_add_option_callback(&opt_domain_cb);

	net_dhcpv4_init_option_callback(&opt_pop3_cb, option_pop3_cb,
					OPTION_POP3, buffer,
					sizeof(buffer));

	net_dhcpv4_add_option_callback(&opt_pop3_cb);

	net_dhcpv4_init_option_callback(&opt_invalid_cb, option_invalid_cb,
					OPTION_INVALID, buffer,
					sizeof(buffer));

	net_dhcpv4_add_option_callback(&opt_invalid_cb);
#endif /* CONFIG_NET_DHCPV4_OPTION_CALLBACKS */

#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS_VENDOR_SPECIFIC
	net_dhcpv4_init_option_vendor_callback(&opt_vs_string_cb, vendor_specific_string_cb,
					       OPTION_VENDOR_STRING, buffer,
					       sizeof(buffer));

	net_dhcpv4_add_option_vendor_callback(&opt_vs_string_cb);

	net_dhcpv4_init_option_vendor_callback(&opt_vs_byte_cb, vendor_specific_byte_cb,
					       OPTION_VENDOR_BYTE, buffer,
					       sizeof(buffer));

	net_dhcpv4_add_option_vendor_callback(&opt_vs_byte_cb);

	net_dhcpv4_init_option_vendor_callback(&opt_vs_empty_cb, vendor_specific_empty_cb,
					       OPTION_VENDOR_EMPTY, buffer,
					       sizeof(buffer));

	net_dhcpv4_add_option_vendor_callback(&opt_vs_empty_cb);

	net_dhcpv4_init_option_vendor_callback(&opt_vs_invalid_cb, option_invalid_cb,
					       OPTION_INVALID, buffer,
					       sizeof(buffer));

	net_dhcpv4_add_option_vendor_callback(&opt_vs_invalid_cb);


#endif /* CONFIG_NET_DHCPV4_OPTION_CALLBACKS_VENDOR_SPECIFIC */

	iface = net_if_get_first_by_type(&NET_L2_GET_NAME(DUMMY));
	if (!iface) {
		zassert_true(false, "Interface not available");
	}

	net_dhcpv4_start(iface);

#ifdef CONFIG_NET_DHCPV4_OPTION_CALLBACKS_VENDOR_SPECIFIC
	while (event_count < 16) {
#elif defined(CONFIG_NET_DHCPV4_OPTION_CALLBACKS)
	while (event_count < 10) {
#else
	while (event_count < 5) {
#endif
		if (k_sem_take(&test_lock, WAIT_TIME)) {
			zassert_true(false, "Timeout while waiting");
		}
	}
}

/**test case main entry */
ZTEST_SUITE(dhcpv4_tests, NULL, NULL, NULL, NULL, NULL);