lwip/test/unit/dhcp/test_dhcp.c

#include "test_dhcp.h"

#include "lwip/netif.h"
#include "lwip/dhcp.h"
#include "netif/etharp.h"

struct netif net_test;

static const u8_t broadcast[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

static const u8_t magic_cookie[] = { 0x63, 0x82, 0x53, 0x63 };

static u8_t dhcp_offer[] = {
    0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d, // To unit
    0x00, 0x0F, 0xEE, 0x30, 0xAB, 0x22, // From Remote host
    0x08, 0x00, // Protocol: IP
    0x45, 0x10, 0x01, 0x48, 0x00, 0x00, 0x00, 0x00, 0x80, 0x11, 0x36, 0xcc, 0xc3, 0xaa, 0xbd, 0xab, 0xc3, 0xaa, 0xbd, 0xc8, // IP header
    0x00, 0x43, 0x00, 0x44, 0x01, 0x34, 0x00, 0x00, // UDP header

    0x02, // Type == Boot reply
    0x01, 0x06, // Hw Ethernet, 6 bytes addrlen
    0x00, // 0 hops
    0xAA, 0xAA, 0xAA, 0xAA, // Transaction id, will be overwritten
    0x00, 0x00, // 0 seconds elapsed
    0x00, 0x00, // Flags (unicast)
    0x00, 0x00, 0x00, 0x00, // Client ip
    0xc3, 0xaa, 0xbd, 0xc8, // Your IP
    0xc3, 0xaa, 0xbd, 0xab, // DHCP server ip
    0x00, 0x00, 0x00, 0x00, // relay agent
    0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // MAC addr + padding

    // Empty server name and boot file name
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00,

    0x63, 0x82, 0x53, 0x63, // Magic cookie
    0x35, 0x01, 0x02, // Message type: Offer
    0x36, 0x04, 0xc3, 0xaa, 0xbd, 0xab, // Server identifier (IP)
    0x33, 0x04, 0x00, 0x00, 0x00, 0x78, // Lease time 2 minutes
    0x03, 0x04, 0xc3, 0xaa, 0xbd, 0xab, // Router IP
    0x01, 0x04, 0xff, 0xff, 0xff, 0x00, // Subnet mask
    0xff, // End option
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Padding
};

static u8_t dhcp_ack[] = {
    0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d, // To unit
    0x00, 0x0f, 0xEE, 0x30, 0xAB, 0x22, // From remote host
    0x08, 0x00, // Proto IP
    0x45, 0x10, 0x01, 0x48, 0x00, 0x00, 0x00, 0x00, 0x80, 0x11, 0x36, 0xcc, 0xc3, 0xaa, 0xbd, 0xab, 0xc3, 0xaa, 0xbd, 0xc8, // IP header
    0x00, 0x43, 0x00, 0x44, 0x01, 0x34, 0x00, 0x00, // UDP header
    0x02, // Bootp reply
    0x01, 0x06, // Hw type Eth, len 6
    0x00, // 0 hops
    0xAA, 0xAA, 0xAA, 0xAA,
    0x00, 0x00, // 0 seconds elapsed
    0x00, 0x00, // Flags (unicast)
    0x00, 0x00, 0x00, 0x00, // Client IP
    0xc3, 0xaa, 0xbd, 0xc8, // Your IP
    0xc3, 0xaa, 0xbd, 0xab, // DHCP server IP
    0x00, 0x00, 0x00, 0x00, // Relay agent
    0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Macaddr + padding

    // Empty server name and boot file name
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00,

    0x63, 0x82, 0x53, 0x63, // Magic cookie
    0x35, 0x01, 0x05, // Dhcp message type ack
    0x36, 0x04, 0xc3, 0xaa, 0xbd, 0xab, // DHCP server identifier
    0x33, 0x04, 0x00, 0x00, 0x00, 0x78, // Lease time 2 minutes
    0x03, 0x04, 0xc3, 0xaa, 0xbd, 0xab, // Router IP
    0x01, 0x04, 0xff, 0xff, 0xff, 0x00, // Netmask
    0xff, // End marker

    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Padding
};

static const u8_t arpreply[] = {
    0x00, 0x23, 0xC1, 0xDE, 0xD0, 0x0D, // dst mac
    0x00, 0x32, 0x44, 0x20, 0x01, 0x02, // src mac
    0x08, 0x06, // proto arp
    0x00, 0x01, // hw eth
    0x08, 0x00, // proto ip
    0x06, // hw addr len 6
    0x04, // proto addr len 4
    0x00, 0x02, // arp reply
    0x00, 0x32, 0x44, 0x20, 0x01, 0x02, // sender mac
    0xc3, 0xaa, 0xbd, 0xc8, // sender ip
    0x00, 0x23, 0xC1, 0xDE, 0xD0, 0x0D, // target mac
    0x00, 0x00, 0x00, 0x00, // target ip
};

static int txpacket;
static enum tcase {
  TEST_LWIP_DHCP,
  TEST_LWIP_DHCP_NAK,
  TEST_LWIP_DHCP_RELAY,
  TEST_LWIP_DHCP_NAK_NO_ENDMARKER,
} tcase;

static int debug = 0;
static void setdebug(int a) {debug = a;}

static int tick = 0;
static void tick_lwip(void)
{
  tick++;
  if (tick % 5 == 0) {
    dhcp_fine_tmr();
  }
  if (tick % 600 == 0) {
    dhcp_coarse_tmr();
  }
}

static void send_pkt(struct netif *netif, const u8_t *data, u32_t len)
{
  struct pbuf *p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
  struct pbuf *q;

  if (debug) {
    // Dump data
    u32_t i;
    printf("RX data (len %d)", p->tot_len);
    for (i = 0; i < len; i++) {
      printf(" %02X", data[i]);
    }
    printf("\n");
  }

  fail_unless(p != NULL);
  for(q = p; q != NULL; q = q->next) {
    memcpy(q->payload, data, q->len);
    data += q->len;
  }
  netif->input(p, netif);
}

static err_t lwip_tx_func(struct netif *netif, struct pbuf *p);

static err_t testif_init(struct netif *netif)
{
  netif->name[0] = 'c';
  netif->name[1] = 'h';
  netif->output = etharp_output;
  netif->linkoutput = lwip_tx_func;
  netif->mtu = 1500;
  netif->hwaddr_len = 6;
  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP;

  netif->hwaddr[0] = 0x00;
  netif->hwaddr[1] = 0x23;
  netif->hwaddr[2] = 0xC1;
  netif->hwaddr[3] = 0xDE;
  netif->hwaddr[4] = 0xD0;
  netif->hwaddr[5] = 0x0D;

  return ERR_OK;
}

static void dhcp_setup(void)
{
  txpacket = 0;
}

static void dhcp_teardown(void)
{
}

static void check_pkt(struct pbuf *p, u32_t pos, const u8_t *mem, u32_t len)
{
  u8_t *data;

  fail_if((pos + len) > p->tot_len);
  while (pos > p->len && p->next) {
    pos -= p->len;
    p = p->next;
  }
  fail_if(p == NULL);
  fail_unless(pos + len <= p->len); // All data we seek within same pbuf

  data = p->payload;
  fail_if(memcmp(&data[pos], mem, len), "data at pos %d, len %d in packet %d did not match", pos, len, txpacket);
}

static void check_pkt_fuzzy(struct pbuf *p, u32_t startpos, const u8_t *mem, u32_t len)
{
  int found;
  u32_t i;
  u8_t *data;

  fail_if((startpos + len) > p->tot_len);
  while (startpos > p->len && p->next) {
    startpos -= p->len;
    p = p->next;
  }
  fail_if(p == NULL);
  fail_unless(startpos + len <= p->len); // All data we seek within same pbuf

  found = 0;
  data = p->payload;
  for (i = startpos; i <= (p->len - len); i++) {
    if (memcmp(&data[i], mem, len) == 0) {
      found = 1;
      break;
    }
  }
  fail_unless(found);
}

static err_t lwip_tx_func(struct netif *netif, struct pbuf *p)
{
  fail_unless(netif == &net_test);
  txpacket++;

  if (debug) {
    struct pbuf *pp = p;
    // Dump data
    printf("TX data (pkt %d, len %d, tick %d)", txpacket, p->tot_len, tick);
    do {
      int i;
      for (i = 0; i < pp->len; i++) {
        printf(" %02X", ((u8_t *) pp->payload)[i]);
      }
      if (pp->next) {
        pp = pp->next;
      }
    } while (pp->next);
    printf("\n");
  }

  switch (tcase) {
  case TEST_LWIP_DHCP:
    switch (txpacket) {
    case 1:
    case 2:
      {
        const u8_t ipproto[] = { 0x08, 0x00 };
        const u8_t bootp_start[] = { 0x01, 0x01, 0x06, 0x00}; // bootp request, eth, hwaddr len 6, 0 hops
        const u8_t ipaddrs[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

        check_pkt(p, 0, broadcast, 6); // eth level dest: broadcast
        check_pkt(p, 6, netif->hwaddr, 6); // eth level src: unit mac

        check_pkt(p, 12, ipproto, sizeof(ipproto)); // eth level proto: ip

        check_pkt(p, 42, bootp_start, sizeof(bootp_start));

        check_pkt(p, 53, ipaddrs, sizeof(ipaddrs));

        check_pkt(p, 70, netif->hwaddr, 6); // mac addr inside bootp

        check_pkt(p, 278, magic_cookie, sizeof(magic_cookie));

        // Check dchp message type, can be at different positions
        if (txpacket == 1) {
          u8_t dhcp_discover_opt[] = { 0x35, 0x01, 0x01 };
          check_pkt_fuzzy(p, 282, dhcp_discover_opt, sizeof(dhcp_discover_opt));
        } else if (txpacket == 2) {
          u8_t dhcp_request_opt[] = { 0x35, 0x01, 0x03 };
          u8_t requested_ipaddr[] = { 0x32, 0x04, 0xc3, 0xaa, 0xbd, 0xc8 }; // Ask for offered IP

          check_pkt_fuzzy(p, 282, dhcp_request_opt, sizeof(dhcp_request_opt));
          check_pkt_fuzzy(p, 282, requested_ipaddr, sizeof(requested_ipaddr));
        }
        break;
      }
    case 3:
    case 4:
    case 5:
      {
        const u8_t arpproto[] = { 0x08, 0x06 };

        check_pkt(p, 0, broadcast, 6); // eth level dest: broadcast
        check_pkt(p, 6, netif->hwaddr, 6); // eth level src: unit mac

        check_pkt(p, 12, arpproto, sizeof(arpproto)); // eth level proto: ip
        break;
      }
    }
    break;

  case TEST_LWIP_DHCP_NAK:
    {
      const u8_t ipproto[] = { 0x08, 0x00 };
      const u8_t bootp_start[] = { 0x01, 0x01, 0x06, 0x00}; // bootp request, eth, hwaddr len 6, 0 hops
      const u8_t ipaddrs[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
      const u8_t dhcp_nak_opt[] = { 0x35, 0x01, 0x04 };
      const u8_t requested_ipaddr[] = { 0x32, 0x04, 0xc3, 0xaa, 0xbd, 0xc8 }; // offered IP

      fail_unless(txpacket == 4);
      check_pkt(p, 0, broadcast, 6); // eth level dest: broadcast
      check_pkt(p, 6, netif->hwaddr, 6); // eth level src: unit mac

      check_pkt(p, 12, ipproto, sizeof(ipproto)); // eth level proto: ip

      check_pkt(p, 42, bootp_start, sizeof(bootp_start));

      check_pkt(p, 53, ipaddrs, sizeof(ipaddrs));

      check_pkt(p, 70, netif->hwaddr, 6); // mac addr inside bootp

      check_pkt(p, 278, magic_cookie, sizeof(magic_cookie));

      check_pkt_fuzzy(p, 282, dhcp_nak_opt, sizeof(dhcp_nak_opt)); // NAK the ack

      check_pkt_fuzzy(p, 282, requested_ipaddr, sizeof(requested_ipaddr));
      break;
    }

  case TEST_LWIP_DHCP_RELAY:
    switch (txpacket) {
    case 1:
    case 2:
      {
        const u8_t ipproto[] = { 0x08, 0x00 };
        const u8_t bootp_start[] = { 0x01, 0x01, 0x06, 0x00}; // bootp request, eth, hwaddr len 6, 0 hops
        const u8_t ipaddrs[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

        check_pkt(p, 0, broadcast, 6); // eth level dest: broadcast
        check_pkt(p, 6, netif->hwaddr, 6); // eth level src: unit mac

        check_pkt(p, 12, ipproto, sizeof(ipproto)); // eth level proto: ip

        check_pkt(p, 42, bootp_start, sizeof(bootp_start));

        check_pkt(p, 53, ipaddrs, sizeof(ipaddrs));

        check_pkt(p, 70, netif->hwaddr, 6); // mac addr inside bootp

        check_pkt(p, 278, magic_cookie, sizeof(magic_cookie));

        // Check dchp message type, can be at different positions
        if (txpacket == 1) {
          u8_t dhcp_discover_opt[] = { 0x35, 0x01, 0x01 };
          check_pkt_fuzzy(p, 282, dhcp_discover_opt, sizeof(dhcp_discover_opt));
        } else if (txpacket == 2) {
          u8_t dhcp_request_opt[] = { 0x35, 0x01, 0x03 };
          u8_t requested_ipaddr[] = { 0x32, 0x04, 0x4f, 0x8a, 0x33, 0x05 }; // Ask for offered IP

          check_pkt_fuzzy(p, 282, dhcp_request_opt, sizeof(dhcp_request_opt));
          check_pkt_fuzzy(p, 282, requested_ipaddr, sizeof(requested_ipaddr));
        }
        break;
      }
    case 3:
    case 4:
    case 5:
      {
        const u8_t arpproto[] = { 0x08, 0x06 };

        check_pkt(p, 0, broadcast, 6); // eth level dest: broadcast
        check_pkt(p, 6, netif->hwaddr, 6); // eth level src: unit mac

        check_pkt(p, 12, arpproto, sizeof(arpproto)); // eth level proto: ip
        break;
      }
    case 6:
    case 7:
      {
        const u8_t fake_arp[6] = { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xab };
        const u8_t ipproto[] = { 0x08, 0x00 };
        const u8_t bootp_start[] = { 0x01, 0x01, 0x06, 0x00}; // bootp request, eth, hwaddr len 6, 0 hops
        const u8_t ipaddrs[] = { 0x00, 0x4f, 0x8a, 0x33, 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
        const u8_t dhcp_request_opt[] = { 0x35, 0x01, 0x03 };

        check_pkt(p, 0, fake_arp, 6); // eth level dest: broadcast
        check_pkt(p, 6, netif->hwaddr, 6); // eth level src: unit mac

        check_pkt(p, 12, ipproto, sizeof(ipproto)); // eth level proto: ip

        check_pkt(p, 42, bootp_start, sizeof(bootp_start));

        check_pkt(p, 53, ipaddrs, sizeof(ipaddrs));

        check_pkt(p, 70, netif->hwaddr, 6); // mac addr inside bootp

        check_pkt(p, 278, magic_cookie, sizeof(magic_cookie));

        // Check dchp message type, can be at different positions
        check_pkt_fuzzy(p, 282, dhcp_request_opt, sizeof(dhcp_request_opt));
        break;
      }
    }
    break;

  default:
    break;
  }

  return ERR_OK;
}

/*
 * Test basic happy flow DHCP session.
 * Validate that xid is checked.
 */
START_TEST(test_dhcp)
{
  struct ip_addr addr;
  struct ip_addr netmask;
  struct ip_addr gw;
  int i;
  u32_t xid;
  LWIP_UNUSED_ARG(_i);

  tcase = TEST_LWIP_DHCP;
  setdebug(0);

  IP4_ADDR(&addr, 0, 0, 0, 0);
  IP4_ADDR(&netmask, 0, 0, 0, 0);
  IP4_ADDR(&gw, 0, 0, 0, 0);

  netif_add(&net_test, &addr, &netmask, &gw, &net_test, testif_init, ethernet_input);

  dhcp_start(&net_test);

  fail_unless(txpacket == 1); // DHCP discover sent
  xid = net_test.dhcp->xid; // Write bad xid, not using htonl!
  memcpy(&dhcp_offer[46], &xid, 4);
  send_pkt(&net_test, dhcp_offer, sizeof(dhcp_offer));

  // Interface down
  fail_if(netif_is_up(&net_test));

  // IP addresses should be zero
  fail_if(memcmp(&addr, &net_test.ip_addr, sizeof(struct ip_addr)));
  fail_if(memcmp(&netmask, &net_test.netmask, sizeof(struct ip_addr)));
  fail_if(memcmp(&gw, &net_test.gw, sizeof(struct ip_addr)));

  fail_unless(txpacket == 1, "TX %d packets, expected 1", txpacket); // Nothing more sent
  xid = htonl(net_test.dhcp->xid);
  memcpy(&dhcp_offer[46], &xid, 4); // insert correct transaction id
  send_pkt(&net_test, dhcp_offer, sizeof(dhcp_offer));

  fail_unless(txpacket == 2, "TX %d packets, expected 2", txpacket); // DHCP request sent
  xid = net_test.dhcp->xid; // Write bad xid, not using htonl!
  memcpy(&dhcp_ack[46], &xid, 4);
  send_pkt(&net_test, dhcp_ack, sizeof(dhcp_ack));

  fail_unless(txpacket == 2, "TX %d packets, still expected 2", txpacket); // No more sent
  xid = htonl(net_test.dhcp->xid); // xid updated
  memcpy(&dhcp_ack[46], &xid, 4); // insert transaction id
  send_pkt(&net_test, dhcp_ack, sizeof(dhcp_ack));

  for (i = 0; i < 20; i++) {
    tick_lwip();
  }
  fail_unless(txpacket == 4, "TX %d packets, expected 4", txpacket); // ARP requests sent

  // Interface up
  fail_unless(netif_is_up(&net_test));

  // Now it should have taken the IP
  IP4_ADDR(&addr, 195, 170, 189, 200);
  IP4_ADDR(&netmask, 255, 255, 255, 0);
  IP4_ADDR(&gw, 195, 170, 189, 171);
  fail_if(memcmp(&addr, &net_test.ip_addr, sizeof(struct ip_addr)));
  fail_if(memcmp(&netmask, &net_test.netmask, sizeof(struct ip_addr)));
  fail_if(memcmp(&gw, &net_test.gw, sizeof(struct ip_addr)));

  netif_remove(&net_test);
}
END_TEST

/*
 * Test that IP address is not taken and NAK is sent if someone
 * replies to ARP requests for the offered address.
 */
START_TEST(test_dhcp_nak)
{
  struct ip_addr addr;
  struct ip_addr netmask;
  struct ip_addr gw;
  u32_t xid;
  LWIP_UNUSED_ARG(_i);

  tcase = TEST_LWIP_DHCP;
  setdebug(0);

  IP4_ADDR(&addr, 0, 0, 0, 0);
  IP4_ADDR(&netmask, 0, 0, 0, 0);
  IP4_ADDR(&gw, 0, 0, 0, 0);

  netif_add(&net_test, &addr, &netmask, &gw, &net_test, testif_init, ethernet_input);

  dhcp_start(&net_test);

  fail_unless(txpacket == 1); // DHCP discover sent
  xid = net_test.dhcp->xid; // Write bad xid, not using htonl!
  memcpy(&dhcp_offer[46], &xid, 4);
  send_pkt(&net_test, dhcp_offer, sizeof(dhcp_offer));

  // Interface down
  fail_if(netif_is_up(&net_test));

  // IP addresses should be zero
  fail_if(memcmp(&addr, &net_test.ip_addr, sizeof(struct ip_addr)));
  fail_if(memcmp(&netmask, &net_test.netmask, sizeof(struct ip_addr)));
  fail_if(memcmp(&gw, &net_test.gw, sizeof(struct ip_addr)));

  fail_unless(txpacket == 1); // Nothing more sent
  xid = htonl(net_test.dhcp->xid);
  memcpy(&dhcp_offer[46], &xid, 4); // insert correct transaction id
  send_pkt(&net_test, dhcp_offer, sizeof(dhcp_offer));

  fail_unless(txpacket == 2); // DHCP request sent
  xid = net_test.dhcp->xid; // Write bad xid, not using htonl!
  memcpy(&dhcp_ack[46], &xid, 4);
  send_pkt(&net_test, dhcp_ack, sizeof(dhcp_ack));

  fail_unless(txpacket == 2); // No more sent
  xid = htonl(net_test.dhcp->xid); // xid updated
  memcpy(&dhcp_ack[46], &xid, 4); // insert transaction id
  send_pkt(&net_test, dhcp_ack, sizeof(dhcp_ack));

  fail_unless(txpacket == 3); // ARP request sent

  tcase = TEST_LWIP_DHCP_NAK; // Switch testcase

  // Send arp reply, mark offered IP as taken
  send_pkt(&net_test, arpreply, sizeof(arpreply));

  fail_unless(txpacket == 4); // DHCP nak sent

  netif_remove(&net_test);
}
END_TEST

/*
 * Test case based on captured data where
 * replies are sent from a different IP than the
 * one the client unicasted to.
 */
START_TEST(test_dhcp_relayed)
{
  u8_t relay_offer[] = {
  0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d,
  0x00, 0x22, 0x93, 0x5a, 0xf7, 0x60,
  0x08, 0x00, 0x45, 0x00,
  0x01, 0x38, 0xfd, 0x53, 0x00, 0x00, 0x40, 0x11,
  0x78, 0x46, 0x4f, 0x8a, 0x32, 0x02, 0x4f, 0x8a,
  0x33, 0x05, 0x00, 0x43, 0x00, 0x44, 0x01, 0x24,
  0x00, 0x00, 0x02, 0x01, 0x06, 0x00, 0x51, 0x35,
  0xb6, 0xa0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x4f, 0x8a, 0x33, 0x05, 0x00, 0x00,
  0x00, 0x00, 0x0a, 0xb5, 0x04, 0x01, 0x00, 0x23,
  0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x63, 0x82,
  0x53, 0x63, 0x01, 0x04, 0xff, 0xff, 0xfe, 0x00,
  0x03, 0x04, 0x4f, 0x8a, 0x32, 0x01, 0x06, 0x08,
  0x4f, 0x8a, 0x00, 0xb4, 0x55, 0x08, 0x1f, 0xd1,
  0x1c, 0x04, 0x4f, 0x8a, 0x33, 0xff, 0x33, 0x04,
  0x00, 0x00, 0x54, 0x49, 0x35, 0x01, 0x02, 0x36,
  0x04, 0x0a, 0xb5, 0x04, 0x01, 0xff
  };

  u8_t relay_ack1[] = {
  0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x22,
  0x93, 0x5a, 0xf7, 0x60, 0x08, 0x00, 0x45, 0x00,
  0x01, 0x38, 0xfd, 0x55, 0x00, 0x00, 0x40, 0x11,
  0x78, 0x44, 0x4f, 0x8a, 0x32, 0x02, 0x4f, 0x8a,
  0x33, 0x05, 0x00, 0x43, 0x00, 0x44, 0x01, 0x24,
  0x00, 0x00, 0x02, 0x01, 0x06, 0x00, 0x51, 0x35,
  0xb6, 0xa1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x4f, 0x8a, 0x33, 0x05, 0x00, 0x00,
  0x00, 0x00, 0x0a, 0xb5, 0x04, 0x01, 0x00, 0x23,
  0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x63, 0x82,
  0x53, 0x63, 0x01, 0x04, 0xff, 0xff, 0xfe, 0x00,
  0x03, 0x04, 0x4f, 0x8a, 0x32, 0x01, 0x06, 0x08,
  0x4f, 0x8a, 0x00, 0xb4, 0x55, 0x08, 0x1f, 0xd1,
  0x1c, 0x04, 0x4f, 0x8a, 0x33, 0xff, 0x33, 0x04,
  0x00, 0x00, 0x54, 0x49, 0x35, 0x01, 0x05, 0x36,
  0x04, 0x0a, 0xb5, 0x04, 0x01, 0xff
  };

  u8_t relay_ack2[] = {
  0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d,
  0x00, 0x22, 0x93, 0x5a, 0xf7, 0x60,
  0x08, 0x00, 0x45, 0x00,
  0x01, 0x38, 0xfa, 0x18, 0x00, 0x00, 0x40, 0x11,
  0x7b, 0x81, 0x4f, 0x8a, 0x32, 0x02, 0x4f, 0x8a,
  0x33, 0x05, 0x00, 0x43, 0x00, 0x44, 0x01, 0x24,
  0x00, 0x00, 0x02, 0x01, 0x06, 0x00, 0x49, 0x8b,
  0x6e, 0xab, 0x00, 0x00, 0x00, 0x00, 0x4f, 0x8a,
  0x33, 0x05, 0x4f, 0x8a, 0x33, 0x05, 0x00, 0x00,
  0x00, 0x00, 0x0a, 0xb5, 0x04, 0x01, 0x00, 0x23,
  0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x63, 0x82,
  0x53, 0x63, 0x01, 0x04, 0xff, 0xff, 0xfe, 0x00,
  0x03, 0x04, 0x4f, 0x8a, 0x32, 0x01, 0x06, 0x08,
  0x4f, 0x8a, 0x00, 0xb4, 0x55, 0x08, 0x1f, 0xd1,
  0x1c, 0x04, 0x4f, 0x8a, 0x33, 0xff, 0x33, 0x04,
  0x00, 0x00, 0x54, 0x60, 0x35, 0x01, 0x05, 0x36,
  0x04, 0x0a, 0xb5, 0x04, 0x01, 0xff };

  const u8_t arp_resp[] = {
  0x00, 0x23, 0xc1, 0xde, 0xd0, 0x0d, // DEST
  0x00, 0x22, 0x93, 0x5a, 0xf7, 0x60, // SRC
  0x08, 0x06, // Type: ARP
  0x00, 0x01, // HW: Ethernet
  0x08, 0x00, // PROTO: IP
  0x06, // HW size
  0x04, // PROTO size
  0x00, 0x02, // OPCODE: Reply

  0x12, 0x34, 0x56, 0x78, 0x9a, 0xab, // Target MAC
  0x4f, 0x8a, 0x32, 0x01, // Target IP

  0x00, 0x23, 0xc1, 0x00, 0x06, 0x50, // src mac
  0x4f, 0x8a, 0x33, 0x05, // src ip

  // Padding follows..
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00 };

  struct ip_addr addr;
  struct ip_addr netmask;
  struct ip_addr gw;
  int i;
  u32_t xid;
  LWIP_UNUSED_ARG(_i);

  tcase = TEST_LWIP_DHCP_RELAY;
  setdebug(0);

  IP4_ADDR(&addr, 0, 0, 0, 0);
  IP4_ADDR(&netmask, 0, 0, 0, 0);
  IP4_ADDR(&gw, 0, 0, 0, 0);

  netif_add(&net_test, &addr, &netmask, &gw, &net_test, testif_init, ethernet_input);

  dhcp_start(&net_test);

  fail_unless(txpacket == 1); // DHCP discover sent

  // Interface down
  fail_if(netif_is_up(&net_test));

  // IP addresses should be zero
  fail_if(memcmp(&addr, &net_test.ip_addr, sizeof(struct ip_addr)));
  fail_if(memcmp(&netmask, &net_test.netmask, sizeof(struct ip_addr)));
  fail_if(memcmp(&gw, &net_test.gw, sizeof(struct ip_addr)));

  fail_unless(txpacket == 1); // Nothing more sent
  xid = htonl(net_test.dhcp->xid);
  memcpy(&relay_offer[46], &xid, 4); // insert correct transaction id
  send_pkt(&net_test, relay_offer, sizeof(relay_offer));

  // request sent?
  fail_unless(txpacket == 2, "txpkt = %d, should be 2", txpacket);
  xid = htonl(net_test.dhcp->xid); // xid updated
  memcpy(&relay_ack1[46], &xid, 4); // insert transaction id
  send_pkt(&net_test, relay_ack1, sizeof(relay_ack1));

  for (i = 0; i < 25; i++) {
    tick_lwip();
  }
  fail_unless(txpacket == 4, "txpkt should be 4, is %d", txpacket); // ARP requests sent

  // Interface up
  fail_unless(netif_is_up(&net_test));

  // Now it should have taken the IP
  IP4_ADDR(&addr, 79, 138, 51, 5);
  IP4_ADDR(&netmask, 255, 255, 254, 0);
  IP4_ADDR(&gw, 79, 138, 50, 1);
  fail_if(memcmp(&addr, &net_test.ip_addr, sizeof(struct ip_addr)));
  fail_if(memcmp(&netmask, &net_test.netmask, sizeof(struct ip_addr)));
  fail_if(memcmp(&gw, &net_test.gw, sizeof(struct ip_addr)));

  fail_unless(txpacket == 4, "txpacket = %d", txpacket);

  for (i = 0; i < 108000 - 25; i++) {
    tick_lwip();
  }

  fail_unless(netif_is_up(&net_test));
  fail_unless(txpacket == 5, "txpacket = %d", txpacket);

  // We need to send arp response here..

  send_pkt(&net_test, arp_resp, sizeof(arp_resp));

  fail_unless(txpacket == 6, "txpacket = %d", txpacket);
  fail_unless(netif_is_up(&net_test));

  xid = htonl(net_test.dhcp->xid); // xid updated
  memcpy(&relay_ack2[46], &xid, 4); // insert transaction id
  send_pkt(&net_test, relay_ack2, sizeof(relay_ack2));

  for (i = 0; i < 100000; i++) {
    tick_lwip();
  }

  fail_unless(txpacket == 6, "txpacket = %d", txpacket);

  netif_remove(&net_test);

}
END_TEST

START_TEST(test_dhcp_nak_no_endmarker)
{
  struct ip_addr addr;
  struct ip_addr netmask;
  struct ip_addr gw;

  u8_t dhcp_nack_no_endmarker[] = {
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x54, 0x75,
    0xd0, 0x26, 0xd0, 0x0d, 0x08, 0x00, 0x45, 0x00,
    0x01, 0x15, 0x38, 0x86, 0x00, 0x00, 0xff, 0x11,
    0xc0, 0xa8, 0xc0, 0xa8, 0x01, 0x01, 0xff, 0xff,
    0xff, 0xff, 0x00, 0x43, 0x00, 0x44, 0x01, 0x01,
    0x00, 0x00, 0x02, 0x01, 0x06, 0x00, 0x7a, 0xcb,
    0xba, 0xf2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x23,
    0xc1, 0xde, 0xd0, 0x0d, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x63, 0x82,
    0x53, 0x63, 0x35, 0x01, 0x06, 0x36, 0x04, 0xc0,
    0xa8, 0x01, 0x01, 0x31, 0xef, 0xad, 0x72, 0x31,
    0x43, 0x4e, 0x44, 0x30, 0x32, 0x35, 0x30, 0x43,
    0x52, 0x47, 0x44, 0x38, 0x35, 0x36, 0x3c, 0x08,
    0x4d, 0x53, 0x46, 0x54, 0x20, 0x35, 0x2e, 0x30,
    0x37, 0x0d, 0x01, 0x0f, 0x03, 0x06, 0x2c, 0x2e,
    0x2f, 0x1f, 0x21, 0x79, 0xf9, 0x2b, 0xfc, 0xff,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe2, 0x71,
    0xf3, 0x5b, 0xe2, 0x71, 0x2e, 0x01, 0x08, 0x03,
    0x04, 0xc0, 0xa8, 0x01, 0x01, 0xff, 0xeb, 0x1e,
    0x44, 0xec, 0xeb, 0x1e, 0x30, 0x37, 0x0c, 0x01,
    0x0f, 0x03, 0x06, 0x2c, 0x2e, 0x2f, 0x1f, 0x21,
    0x79, 0xf9, 0x2b, 0xff, 0x25, 0xc0, 0x09, 0xd6,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
  };

  tcase = TEST_LWIP_DHCP_NAK_NO_ENDMARKER;
  setdebug(0);

  IP4_ADDR(&addr, 0, 0, 0, 0);
  IP4_ADDR(&netmask, 0, 0, 0, 0);
  IP4_ADDR(&gw, 0, 0, 0, 0);

  netif_add(&net_test, &addr, &netmask, &gw, &net_test, testif_init, ethernet_input);

  dhcp_start(&net_test);

  fail_unless(txpacket == 1); // DHCP discover sent
  u32_t xid = net_test.dhcp->xid; // Write bad xid, not using htonl!
  memcpy(&dhcp_offer[46], &xid, 4);
  send_pkt(&net_test, dhcp_offer, sizeof(dhcp_offer));

  // Interface down
  fail_if(netif_is_up(&net_test));

  // IP addresses should be zero
  fail_if(memcmp(&addr, &net_test.ip_addr, sizeof(struct ip_addr)));
  fail_if(memcmp(&netmask, &net_test.netmask, sizeof(struct ip_addr)));
  fail_if(memcmp(&gw, &net_test.gw, sizeof(struct ip_addr)));

  fail_unless(txpacket == 1); // Nothing more sent
  xid = htonl(net_test.dhcp->xid);
  memcpy(&dhcp_offer[46], &xid, 4); // insert correct transaction id
  send_pkt(&net_test, dhcp_offer, sizeof(dhcp_offer));
  
  fail_unless(net_test.dhcp->state == DHCP_REQUESTING);

  fail_unless(txpacket == 2); // No more sent
  xid = htonl(net_test.dhcp->xid); // xid updated
  memcpy(&dhcp_nack_no_endmarker[46], &xid, 4); // insert transaction id
  send_pkt(&net_test, dhcp_nack_no_endmarker, sizeof(dhcp_nack_no_endmarker));

  // NAK should put us in another state for a while, no other way detecting it
  fail_unless(net_test.dhcp->state != DHCP_REQUESTING);

  netif_remove(&net_test);
}
END_TEST


/** Create the suite including all tests for this module */
Suite *
dhcp_suite(void)
{
  TFun tests[] = {
    test_dhcp,
    test_dhcp_nak,
    test_dhcp_relayed,
    test_dhcp_nak_no_endmarker
  };
  return create_suite("DHCP", tests, sizeof(tests)/sizeof(TFun), dhcp_setup, dhcp_teardown);
}