pcapif.c

NXPl788上lwip的无操作系统移植,基于Embest开发板

  printf("Using adapter: \"%s\"\n", pa->description);
  pcap_freealldevs(alldevs);

#if PCAPIF_HANDLE_LINKSTATE
  pa->link_state = pcapifh_linkstate_init(pa->name);
  pa->last_link_event = PCAPIF_LINKEVENT_UNKNOWN;
#endif /* PCAPIF_HANDLE_LINKSTATE */

  return pa;
}

#if PCAPIF_HANDLE_LINKSTATE
void
pcapif_check_linkstate(void *netif)
{
  struct pcapif_private *pa = (struct pcapif_private*)((struct netif *)netif)->state;
  enum pcapifh_link_event le;

  le = pcapifh_linkstate_get(pa->link_state);

  if (pa->last_link_event != le) {
    pa->last_link_event = le;
    switch (le) {
      case PCAPIF_LINKEVENT_UP: {
        PCAPIF_NOTIFY_LINKSTATE(netif, netif_set_link_up);
        break;
      }
      case PCAPIF_LINKEVENT_DOWN: {
        PCAPIF_NOTIFY_LINKSTATE(netif, netif_set_link_down);
        break;
      }
    }
  }
  sys_timeout(PCAPIF_LINKCHECK_INTERVAL_MS, pcapif_check_linkstate, netif);
}
#endif /* PCAPIF_HANDLE_LINKSTATE */


/**
 * Close the adapter (no more packets can be sent or received)
 *
 * @param netif netif to shutdown
 */
void
pcapif_shutdown(struct netif *netif)
{
  struct pcapif_private *pa = (struct pcapif_private*)netif->state;
  if (pa) {
#if PCAPIF_RX_USE_THREAD
    pa->rx_run = 0;
#endif /* PCAPIF_RX_USE_THREAD */
    if (pa->adapter) {
      pcap_breakloop(pa->adapter);
      pcap_close(pa->adapter);
    }
#if PCAPIF_RX_USE_THREAD
    /* wait for rxthread to end */
    while(pa->rx_running);
#endif /* PCAPIF_RX_USE_THREAD */
#if PCAPIF_HANDLE_LINKSTATE
    pcapifh_linkstate_close(pa->link_state);
#endif /* PCAPIF_HANDLE_LINKSTATE */
    free(pa);
  }
}

#if PCAPIF_RX_USE_THREAD
/** RX running in its own thread */
static void
pcapif_input_thread(void *arg)
{
  struct netif *netif = (struct netif *)arg;
  struct pcapif_private *pa = (struct pcapif_private*)netif->state;
  int ret;
  do
  {
    ret = pcap_loop(pa->adapter, -1, pcapif_input, (u_char*)pa);
    if (ret < 0)
    {
      sys_msleep(1);
    }
  } while (pa->rx_run);
  pa->rx_running = 0;
}
#endif /* PCAPIF_RX_USE_THREAD */

/** Low-level initialization: find the correct adapter and initialize it.
 */
static void
pcapif_low_level_init(struct netif *netif)
{
  u8_t my_mac_addr[ETHARP_HWADDR_LEN] = LWIP_MAC_ADDR_BASE;
  int adapter_num = PACKET_LIB_ADAPTER_NR;
  struct pcapif_private *pa;

#ifdef PACKET_LIB_GET_ADAPTER_NETADDRESS
  ip_addr_t netaddr;
#define GUID_LEN 128
  char guid[GUID_LEN + 1];
  memset(&guid, 0, sizeof(guid));
  PACKET_LIB_GET_ADAPTER_NETADDRESS(&netaddr);
  if (get_adapter_index_from_addr((struct in_addr *)&netaddr, guid, GUID_LEN) < 0) {
     printf("ERROR initializing network adapter, failed to get GUID for network address %s\n", ip_ntoa(&netaddr));
     LWIP_ASSERT("ERROR initializing network adapter, failed to get GUID for network address!", 0);
     return;
  }
  adapter_num = get_adapter_index(guid);
  if (adapter_num < 0) {
     printf("ERROR finding network adapter with GUID \"%s\"!\n", guid);
     LWIP_ASSERT("ERROR finding network adapter with expected GUID!", 0);
     return;
  }

#else /* PACKET_LIB_GET_ADAPTER_NETADDRESS */
#ifdef PACKET_LIB_ADAPTER_GUID
  /* get adapter index for guid string */
  adapter_num = get_adapter_index(PACKET_LIB_ADAPTER_GUID);
  if (adapter_num < 0) {
    printf("ERROR finding network adapter with GUID \"%s\"!\n", PACKET_LIB_ADAPTER_GUID);
    LWIP_ASSERT("ERROR initializing network adapter!\n", 0);
    return;
  }
#endif /* PACKET_LIB_ADAPTER_GUID */
#endif /* PACKET_LIB_GET_ADAPTER_NETADDRESS */

  /* Do whatever else is needed to initialize interface. */
  pa = pcapif_init_adapter(adapter_num, netif);
  if (pa == NULL) {
    printf("ERROR initializing network adapter %d!\n", PACKET_LIB_ADAPTER_NR);
    LWIP_ASSERT("ERROR initializing network adapter!", 0);
    return;
  }
  netif->state = pa;

  /* change the MAC address to a unique value
     so that multiple ethernetifs are supported */
  /* @todo: this does NOT support multiple processes using this adapter! */
  my_mac_addr[ETHARP_HWADDR_LEN - 1] += netif->num;
  /* Copy MAC addr */
  memcpy(&netif->hwaddr, my_mac_addr, ETHARP_HWADDR_LEN);

  /* get the initial link state of the selected interface */
#if PCAPIF_HANDLE_LINKSTATE
  pa->last_link_event = pcapifh_linkstate_get(pa->link_state);
  if (pa->last_link_event == PCAPIF_LINKEVENT_DOWN) {
    netif_set_link_down(netif);
  } else {
    netif_set_link_up(netif);
  }
  sys_timeout(PCAPIF_LINKCHECK_INTERVAL_MS, pcapif_check_linkstate, netif);
#endif /* PCAPIF_HANDLE_LINKSTATE */

#if PCAPIF_RX_USE_THREAD
  pa->rx_run = 1;
  pa->rx_running = 1;
  sys_thread_new("pktif_rxthread", pcapif_input_thread, netif, 0, 0);
#endif

  LWIP_DEBUGF(NETIF_DEBUG, ("pktif: eth_addr %02X%02X%02X%02X%02X%02X\n",netif->hwaddr[0],netif->hwaddr[1],netif->hwaddr[2],netif->hwaddr[3],netif->hwaddr[4],netif->hwaddr[5]));
}

/** low_level_output():
 * Transmit a packet. The packet is contained in the pbuf that is passed to
 * the function. This pbuf might be chained.
 */
static err_t
pcapif_low_level_output(struct netif *netif, struct pbuf *p)
{
  struct pbuf *q;
  unsigned char buffer[1520];
  unsigned char *buf = buffer;
  unsigned char *ptr;
  struct eth_hdr *ethhdr;
  u16_t tot_len = p->tot_len - ETH_PAD_SIZE;
  struct pcapif_private *pa = (struct pcapif_private*)netif->state;

#if defined(LWIP_DEBUG) && LWIP_NETIF_TX_SINGLE_PBUF
  LWIP_ASSERT("p->next == NULL && p->len == p->tot_len", p->next == NULL && p->len == p->tot_len);
#endif

  /* initiate transfer */
  if (p->len == p->tot_len) {
    /* no pbuf chain, don't have to copy -> faster */
    buf = &((unsigned char*)p->payload)[ETH_PAD_SIZE];
  } else {
    /* pbuf chain, copy into contiguous buffer */
    if (p->tot_len >= sizeof(buffer)) {
      LINK_STATS_INC(link.lenerr);
      LINK_STATS_INC(link.drop);
      snmp_inc_ifoutdiscards(netif);
      return ERR_BUF;
    }
    ptr = buffer;
    for(q = p; q != NULL; q = q->next) {
      /* Send the data from the pbuf to the interface, one pbuf at a
         time. The size of the data in each pbuf is kept in the ->len
         variable. */
      /* send data from(q->payload, q->len); */
      LWIP_DEBUGF(NETIF_DEBUG, ("netif: send ptr %p q->payload %p q->len %i q->next %p\n", ptr, q->payload, (int)q->len, (void*)q->next));
      if (q == p) {
        memcpy(ptr, &((char*)q->payload)[ETH_PAD_SIZE], q->len - ETH_PAD_SIZE);
        ptr += q->len - ETH_PAD_SIZE;
      } else {
        memcpy(ptr, q->payload, q->len);
        ptr += q->len;
      }
    }
  }

  /* signal that packet should be sent */
  if (pcap_sendpacket(pa->adapter, buf, tot_len) < 0) {
    LINK_STATS_INC(link.memerr);
    LINK_STATS_INC(link.drop);
    snmp_inc_ifoutdiscards(netif);
    return ERR_BUF;
  }

  LINK_STATS_INC(link.xmit);
  snmp_add_ifoutoctets(netif, tot_len);
  ethhdr = (struct eth_hdr *)p->payload;
  if ((ethhdr->dest.addr[0] & 1) != 0) {
    /* broadcast or multicast packet*/
    snmp_inc_ifoutnucastpkts(netif);
  } else {
    /* unicast packet */
    snmp_inc_ifoutucastpkts(netif);
  }
  return ERR_OK;
}

/** low_level_input(): Allocate a pbuf and transfer the bytes of the incoming
 * packet from the interface into the pbuf.
 */
static struct pbuf *
pcapif_low_level_input(struct netif *netif, const void *packet, int packet_len)
{
  struct pbuf *p, *q;
  int start;
  int length = packet_len;
  struct eth_addr *dest = (struct eth_addr*)packet;
  struct eth_addr *src = dest + 1;
  int unicast;

  /* MAC filter: only let my MAC or non-unicast through (pcap receives loopback traffic, too) */
  unicast = ((dest->addr[0] & 0x01) == 0);
  if (((memcmp(dest, &netif->hwaddr, ETHARP_HWADDR_LEN)) && unicast) ||
      /* and don't let feedback packets through (limitation in winpcap?) */
      (!memcmp(src, netif->hwaddr, ETHARP_HWADDR_LEN))) {
    /* don't update counters here! */
    return NULL;
  }

  /* We allocate a pbuf chain of pbufs from the pool. */
  p = pbuf_alloc(PBUF_RAW, (u16_t)length + ETH_PAD_SIZE, PBUF_POOL);
  LWIP_DEBUGF(NETIF_DEBUG, ("netif: recv length %i p->tot_len %i\n", length, (int)p->tot_len));

  if (p != NULL) {
    /* We iterate over the pbuf chain until we have read the entire
       packet into the pbuf. */
    start=0;
    for (q = p; q != NULL; q = q->next) {
      u16_t copy_len = q->len;
      /* Read enough bytes to fill this pbuf in the chain. The
         available data in the pbuf is given by the q->len
         variable. */
      /* read data into(q->payload, q->len); */
      LWIP_DEBUGF(NETIF_DEBUG, ("netif: recv start %i length %i q->payload %p q->len %i q->next %p\n", start, length, q->payload, (int)q->len, (void*)q->next));
      if (q == p) {
#if ETH_PAD_SIZE
        LWIP_ASSERT("q->len >= ETH_PAD_SIZE", q->len >= ETH_PAD_SIZE);
        copy_len -= ETH_PAD_SIZE;
#endif /* ETH_PAD_SIZE*/
        memcpy(&((char*)q->payload)[ETH_PAD_SIZE], &((char*)packet)[start], copy_len);
      } else {
        memcpy(q->payload, &((char*)packet)[start], copy_len);
      }
      start += copy_len;
      length -= copy_len;
      if (length <= 0) {
        break;
      }
    }
    LINK_STATS_INC(link.recv);
    snmp_add_ifinoctets(netif, p->tot_len);
    if (unicast) {
      snmp_inc_ifinucastpkts(netif);
    } else {
      snmp_inc_ifinnucastpkts(netif);
    }
  } else {
    /* drop packet(); */
    LINK_STATS_INC(link.memerr);
    LINK_STATS_INC(link.drop);
  }

  return p;
}

/** pcapif_input: This function is called when a packet is ready to be read
 * from the interface. It uses the function low_level_input() that should
 * handle the actual reception of bytes from the network interface.
 */
static void
pcapif_input(u_char *user, const struct pcap_pkthdr *pkt_header, const u_char *packet)
{
  struct pcapif_private *pa = (struct pcapif_private*)user;
  int packet_len = pkt_header->caplen;
  struct netif *netif = (struct netif *)pa->input_fn_arg;
  struct pbuf *p;

  /* move received packet into a new pbuf */
  p = pcapif_low_level_input(netif, packet, packet_len);
  /* no packet could be read, silently ignore this */
  if (p != NULL) {
    /* pass all packets to ethernet_input, which decides what packets it supports */
    if (netif->input(p, netif) != ERR_OK) {
      LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
      pbuf_free(p);
    }
  }
}

/**
 * pcapif_init(): initialization function, pass to netif_add().
 */
err_t
pcapif_init(struct netif *netif)
{
  static int ethernetif_index;

  int local_index;
  SYS_ARCH_DECL_PROTECT(lev);
  SYS_ARCH_PROTECT(lev);
  local_index = ethernetif_index++;
  SYS_ARCH_UNPROTECT(lev);

  netif->name[0] = IFNAME0;
  netif->name[1] = (char)(IFNAME1 + local_index);
  netif->linkoutput = pcapif_low_level_output;
#if LWIP_ARP
  netif->output = etharp_output;
#else /* LWIP_ARP */
  netif->output = NULL; /* not used for PPPoE */
#endif /* LWIP_ARP */
#if LWIP_NETIF_HOSTNAME
  /* Initialize interface hostname */
  netif_set_hostname(netif, "lwip");
#endif /* LWIP_NETIF_HOSTNAME */

  netif->mtu = 1500;
  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_IGMP;
  netif->hwaddr_len = ETHARP_HWADDR_LEN;

  NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, 100000000);

  /* sets link up or down based on current status */
  pcapif_low_level_init(netif);

  return ERR_OK;
}

#if !PCAPIF_RX_USE_THREAD
void
pcapif_poll(struct netif *netif)
{
  struct pcapif_private *pa = (struct pcapif_private*)netif->state;

  int ret;
  do
  {
    ret = pcap_dispatch(pa->adapter, -1, pcapif_input, (u_char*)pa);
  } while(ret > 0);

}
#endif /* !PCAPIF_RX_USE_THREAD */

#endif /* LWIP_ETHERNET */