Ejemplo n.º 1
0
/**
 * Resolve and fill-in Ethernet address header for outgoing IPv6 packet.
 *
 * For IPv6 multicast, corresponding Ethernet addresses
 * are selected and the packet is transmitted on the link.
 *
 * For unicast addresses, ...
 *
 * @TODO anycast addresses
 *
 * @param netif The lwIP network interface which the IP packet will be sent on.
 * @param q The pbuf(s) containing the IP packet to be sent.
 * @param ip6addr The IP address of the packet destination.
 *
 * @return
 * - ERR_RTE No route to destination (no gateway to external networks),
 * or the return type of either etharp_query() or etharp_send_ip().
 */
err_t
ethip6_output(struct netif *netif, struct pbuf *q, ip6_addr_t *ip6addr)
{
  struct eth_addr dest;
  s8_t i;

  /* make room for Ethernet header - should not fail */
  if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
    /* bail out */
    LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
      ("etharp_output: could not allocate room for header.\n"));
    return ERR_BUF;
  }

  /* multicast destination IP address? */
  if (ip6_addr_ismulticast(ip6addr)) {
    /* Hash IP multicast address to MAC address.*/
    dest.addr[0] = 0x33;
    dest.addr[1] = 0x33;
    dest.addr[2] = ((u8_t *)(&(ip6addr->addr[3])))[0];
    dest.addr[3] = ((u8_t *)(&(ip6addr->addr[3])))[1];
    dest.addr[4] = ((u8_t *)(&(ip6addr->addr[3])))[2];
    dest.addr[5] = ((u8_t *)(&(ip6addr->addr[3])))[3];

    /* Send out. */
    return ethip6_send(netif, q, (struct eth_addr*)(netif->hwaddr), &dest);
  }

  /* We have a unicast destination IP address */
  /* TODO anycast? */
  /* Get next hop record. */
  i = nd6_get_next_hop_entry(ip6addr, netif);
  if (i < 0) {
    /* failed to get a next hop neighbor record. */
    return ERR_MEM;
  }

  /* Now that we have a destination record, send or queue the packet. */
  if (neighbor_cache[i].state == ND6_STALE) {
    /* Switch to delay state. */
    neighbor_cache[i].state = ND6_DELAY;
    neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME;
  }
  /* TODO should we send or queue if PROBE? send for now, to let unicast NS pass. */
  if ((neighbor_cache[i].state == ND6_REACHABLE) ||
      (neighbor_cache[i].state == ND6_DELAY) ||
      (neighbor_cache[i].state == ND6_PROBE)) {

    /* Send out. */
    SMEMCPY(dest.addr, neighbor_cache[i].lladdr, 6);
    return ethip6_send(netif, q, (struct eth_addr*)(netif->hwaddr), &dest);
  }

  /* We should queue packet on this interface. */
  pbuf_header(q, -(s16_t)SIZEOF_ETH_HDR);
  return nd6_queue_packet(i, q);
}
Ejemplo n.º 2
0
/** Common code to see if the current input packet matches the pcb
 * (current input packet is accessed via ip(4/6)_current_* macros)
 *
 * @param pcb pcb to check
 * @param inp network interface on which the datagram was received (only used for IPv4)
 * @param broadcast 1 if his is an IPv4 broadcast (global or subnet-only), 0 otherwise (only used for IPv4)
 * @return 1 on match, 0 otherwise
 */
static u8_t ESP_IRAM_ATTR
udp_input_local_match(struct udp_pcb *pcb, struct netif *inp, u8_t broadcast)
{
  LWIP_UNUSED_ARG(inp);       /* in IPv6 only case */
  LWIP_UNUSED_ARG(broadcast); /* in IPv6 only case */

  /* Dual-stack: PCBs listening to any IP type also listen to any IP address */
  if(IP_IS_ANY_TYPE_VAL(pcb->local_ip)) {
#if LWIP_IPV4 && IP_SOF_BROADCAST_RECV
    if((broadcast != 0) && !ip_get_option(pcb, SOF_BROADCAST)) {
      return 0;
    }
#endif /* LWIP_IPV4 && IP_SOF_BROADCAST_RECV */
    return 1;
  }

  /* Only need to check PCB if incoming IP version matches PCB IP version */
  if(IP_ADDR_PCB_VERSION_MATCH_EXACT(pcb, ip_current_dest_addr())) {
    LWIP_ASSERT("UDP PCB: inconsistent local/remote IP versions", IP_IS_V6_VAL(pcb->local_ip) == IP_IS_V6_VAL(pcb->remote_ip));

#if LWIP_IPV4
    /* Special case: IPv4 broadcast: all or broadcasts in my subnet
     * Note: broadcast variable can only be 1 if it is an IPv4 broadcast */
    if(broadcast != 0) {
#if IP_SOF_BROADCAST_RECV
      if(ip_get_option(pcb, SOF_BROADCAST))
#endif /* IP_SOF_BROADCAST_RECV */
      {
        if(ip4_addr_isany(ip_2_ip4(&pcb->local_ip)) ||
          ((ip4_current_dest_addr()->addr == IPADDR_BROADCAST)) ||
           ip4_addr_netcmp(ip_2_ip4(&pcb->local_ip), ip4_current_dest_addr(), netif_ip4_netmask(inp))) {
          return 1;
        }
      }
    } else
#endif /* LWIP_IPV4 */
    /* Handle IPv4 and IPv6: all, multicast or exact match */
    if(ip_addr_isany(&pcb->local_ip) ||
#if LWIP_IPV6_MLD
       (ip_current_is_v6() && ip6_addr_ismulticast(ip6_current_dest_addr())) ||
#endif /* LWIP_IPV6_MLD */
#if LWIP_IGMP
       (!ip_current_is_v6() && ip4_addr_ismulticast(ip4_current_dest_addr())) ||
#endif /* LWIP_IGMP */
       ip_addr_cmp(&pcb->local_ip, ip_current_dest_addr())) {
      return 1;
    }
  }
  
  return 0;
}
Ejemplo n.º 3
0
/**
 * Resolve and fill-in Ethernet address header for outgoing IPv6 packet.
 *
 * For IPv6 multicast, corresponding Ethernet addresses
 * are selected and the packet is transmitted on the link.
 *
 * For unicast addresses, ...
 *
 * @todo anycast addresses
 *
 * @param netif The lwIP network interface which the IP packet will be sent on.
 * @param q The pbuf(s) containing the IP packet to be sent.
 * @param ip6addr The IP address of the packet destination.
 *
 * @return
 * - ERR_RTE No route to destination (no gateway to external networks),
 * or the return type of either nd6_queue_packet() or ethernet_output().
 */
err_t
ethip6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
{
  struct eth_addr dest;
  s8_t i;

  /* multicast destination IP address? */
  if (ip6_addr_ismulticast(ip6addr)) {
    /* Hash IP multicast address to MAC address.*/
    dest.addr[0] = 0x33;
    dest.addr[1] = 0x33;
    dest.addr[2] = ((const u8_t *)(&(ip6addr->addr[3])))[0];
    dest.addr[3] = ((const u8_t *)(&(ip6addr->addr[3])))[1];
    dest.addr[4] = ((const u8_t *)(&(ip6addr->addr[3])))[2];
    dest.addr[5] = ((const u8_t *)(&(ip6addr->addr[3])))[3];

    /* Send out. */
    return ethernet_output(netif, q, (struct eth_addr*)(netif->hwaddr), &dest, ETHTYPE_IPV6);
  }

  /* We have a unicast destination IP address */
  /* @todo anycast? */
  /* Get next hop record. */
  i = nd6_get_next_hop_entry(ip6addr, netif);
  if (i < 0) {
    /* failed to get a next hop neighbor record. */
    return ERR_MEM;
  }

  /* Now that we have a destination record, send or queue the packet. */
  if (neighbor_cache[i].state == ND6_STALE) {
    /* Switch to delay state. */
    neighbor_cache[i].state = ND6_DELAY;
    neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
  }
  /* @todo should we send or queue if PROBE? send for now, to let unicast NS pass. */
  if ((neighbor_cache[i].state == ND6_REACHABLE) ||
      (neighbor_cache[i].state == ND6_DELAY) ||
      (neighbor_cache[i].state == ND6_PROBE)) {

    /* Send out. */
    SMEMCPY(dest.addr, neighbor_cache[i].lladdr, 6);
    return ethernet_output(netif, q, (struct eth_addr*)(netif->hwaddr), &dest, ETHTYPE_IPV6);
  }

  /* We should queue packet on this interface. */
  return nd6_queue_packet(i, q);
}
/**
 * This function is called by the network interface device driver when
 * an IPv6 packet is received. The function does the basic checks of the
 * IP header such as packet size being at least larger than the header
 * size etc. If the packet was not destined for us, the packet is
 * forwarded (using ip6_forward).
 *
 * Finally, the packet is sent to the upper layer protocol input function.
 *
 * @param p the received IPv6 packet (p->payload points to IPv6 header)
 * @param inp the netif on which this packet was received
 * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
 *         processed, but currently always returns ERR_OK)
 */
err_t
ip6_input(struct pbuf *p, struct netif *inp)
{
  struct ip6_hdr *ip6hdr;
  struct netif *netif;
  u8_t nexth;
  u16_t hlen; /* the current header length */
  u8_t i;
#if 0 /*IP_ACCEPT_LINK_LAYER_ADDRESSING*/
  @todo
  int check_ip_src=1;
#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */

  IP6_STATS_INC(ip6.recv);

  /* identify the IP header */
  ip6hdr = (struct ip6_hdr *)p->payload;
  if (IP6H_V(ip6hdr) != 6) {
    LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IPv6 packet dropped due to bad version number %"U32_F"\n",
        IP6H_V(ip6hdr)));
    pbuf_free(p);
    IP6_STATS_INC(ip6.err);
    IP6_STATS_INC(ip6.drop);
    return ERR_OK;
  }

#ifdef LWIP_HOOK_IP6_INPUT
  if (LWIP_HOOK_IP6_INPUT(p, inp)) {
    /* the packet has been eaten */
    return ERR_OK;
  }
#endif

  /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
  if ((IP6_HLEN > p->len) || ((IP6H_PLEN(ip6hdr) + IP6_HLEN) > p->tot_len)) {
    if (IP6_HLEN > p->len) {
      LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
        ("IPv6 header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
            IP6_HLEN, p->len));
    }
    if ((IP6H_PLEN(ip6hdr) + IP6_HLEN) > p->tot_len) {
      LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
        ("IPv6 (plen %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
            IP6H_PLEN(ip6hdr) + IP6_HLEN, p->tot_len));
    }
    /* free (drop) packet pbufs */
    pbuf_free(p);
    IP6_STATS_INC(ip6.lenerr);
    IP6_STATS_INC(ip6.drop);
    return ERR_OK;
  }

  /* Trim pbuf. This should have been done at the netif layer,
   * but we'll do it anyway just to be sure that its done. */
  pbuf_realloc(p, IP6_HLEN + IP6H_PLEN(ip6hdr));

  /* copy IP addresses to aligned ip6_addr_t */
  ip_addr_copy_from_ip6(ip_data.current_iphdr_dest, ip6hdr->dest);
  ip_addr_copy_from_ip6(ip_data.current_iphdr_src, ip6hdr->src);

  /* current header pointer. */
  ip_data.current_ip6_header = ip6hdr;

  /* In netif, used in case we need to send ICMPv6 packets back. */
  ip_data.current_netif = inp;
  ip_data.current_input_netif = inp;

  /* match packet against an interface, i.e. is this packet for us? */
  if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
    /* Always joined to multicast if-local and link-local all-nodes group. */
    if (ip6_addr_isallnodes_iflocal(ip6_current_dest_addr()) ||
        ip6_addr_isallnodes_linklocal(ip6_current_dest_addr())) {
      netif = inp;
    }
#if LWIP_IPV6_MLD
    else if (mld6_lookfor_group(inp, ip6_current_dest_addr())) {
      netif = inp;
    }
#else /* LWIP_IPV6_MLD */
    else if (ip6_addr_issolicitednode(ip6_current_dest_addr())) {
      /* Filter solicited node packets when MLD is not enabled
       * (for Neighbor discovery). */
      netif = NULL;
      for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
        if (ip6_addr_isvalid(netif_ip6_addr_state(inp, i)) &&
            ip6_addr_cmp_solicitednode(ip6_current_dest_addr(), netif_ip6_addr(inp, i))) {
          netif = inp;
          LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: solicited node packet accepted on interface %c%c\n",
              netif->name[0], netif->name[1]));
          break;
        }
      }
    }
#endif /* LWIP_IPV6_MLD */
    else {
      netif = NULL;
    }
  } else {
    /* start trying with inp. if that's not acceptable, start walking the
       list of configured netifs.
       'first' is used as a boolean to mark whether we started walking the list */
    int first = 1;
    netif = inp;
    do {
      /* interface is up? */
      if (netif_is_up(netif)) {
        /* unicast to this interface address? address configured? */
        for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
          if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
              ip6_addr_cmp(ip6_current_dest_addr(), netif_ip6_addr(netif, i))) {
            /* exit outer loop */
            goto netif_found;
          }
        }
      }
      if (ip6_addr_islinklocal(ip6_current_dest_addr())) {
        /* Do not match link-local addresses to other netifs. */
        netif = NULL;
        break;
      }
      if (first) {
        first = 0;
        netif = netif_list;
      } else {
        netif = netif->next;
      }
      if (netif == inp) {
        netif = netif->next;
      }
    } while (netif != NULL);
netif_found:
    LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet accepted on interface %c%c\n",
        netif ? netif->name[0] : 'X', netif? netif->name[1] : 'X'));
  }

  /* "::" packet source address? (used in duplicate address detection) */
  if (ip6_addr_isany(ip6_current_src_addr()) &&
      (!ip6_addr_issolicitednode(ip6_current_dest_addr()))) {
    /* packet source is not valid */
    /* free (drop) packet pbufs */
    LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with src ANY_ADDRESS dropped\n"));
    pbuf_free(p);
    IP6_STATS_INC(ip6.drop);
    goto ip6_input_cleanup;
  }

  /* packet not for us? */
  if (netif == NULL) {
    /* packet not for us, route or discard */
    LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_TRACE, ("ip6_input: packet not for us.\n"));
#if LWIP_IPV6_FORWARD
    /* non-multicast packet? */
    if (!ip6_addr_ismulticast(ip6_current_dest_addr())) {
      /* try to forward IP packet on (other) interfaces */
      ip6_forward(p, ip6hdr, inp);
    }
#endif /* LWIP_IPV6_FORWARD */
    pbuf_free(p);
    goto ip6_input_cleanup;
  }

  /* current netif pointer. */
  ip_data.current_netif = netif;

  /* Save next header type. */
  nexth = IP6H_NEXTH(ip6hdr);

  /* Init header length. */
  hlen = ip_data.current_ip_header_tot_len = IP6_HLEN;

  /* Move to payload. */
  pbuf_header(p, -IP6_HLEN);

  /* Process known option extension headers, if present. */
  while (nexth != IP6_NEXTH_NONE)
  {
    switch (nexth) {
    case IP6_NEXTH_HOPBYHOP:
      LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Hop-by-Hop options header\n"));
      /* Get next header type. */
      nexth = *((u8_t *)p->payload);

      /* Get the header length. */
      hlen = 8 * (1 + *((u8_t *)p->payload + 1));
      ip_data.current_ip_header_tot_len += hlen;

      /* Skip over this header. */
      if (hlen > p->len) {
        LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
          ("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
              hlen, p->len));
        /* free (drop) packet pbufs */
        pbuf_free(p);
        IP6_STATS_INC(ip6.lenerr);
        IP6_STATS_INC(ip6.drop);
        goto ip6_input_cleanup;
      }

      pbuf_header(p, -(s16_t)hlen);
      break;
    case IP6_NEXTH_DESTOPTS:
      LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Destination options header\n"));
      /* Get next header type. */
      nexth = *((u8_t *)p->payload);

      /* Get the header length. */
      hlen = 8 * (1 + *((u8_t *)p->payload + 1));
      ip_data.current_ip_header_tot_len += hlen;

      /* Skip over this header. */
      if (hlen > p->len) {
        LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
          ("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
              hlen, p->len));
        /* free (drop) packet pbufs */
        pbuf_free(p);
        IP6_STATS_INC(ip6.lenerr);
        IP6_STATS_INC(ip6.drop);
        goto ip6_input_cleanup;
      }

      pbuf_header(p, -(s16_t)hlen);
      break;
    case IP6_NEXTH_ROUTING:
      LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Routing header\n"));
      /* Get next header type. */
      nexth = *((u8_t *)p->payload);

      /* Get the header length. */
      hlen = 8 * (1 + *((u8_t *)p->payload + 1));
      ip_data.current_ip_header_tot_len += hlen;

      /* Skip over this header. */
      if (hlen > p->len) {
        LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
          ("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
              hlen, p->len));
        /* free (drop) packet pbufs */
        pbuf_free(p);
        IP6_STATS_INC(ip6.lenerr);
        IP6_STATS_INC(ip6.drop);
        goto ip6_input_cleanup;
      }

      pbuf_header(p, -(s16_t)hlen);
      break;

    case IP6_NEXTH_FRAGMENT:
    {
      struct ip6_frag_hdr * frag_hdr;
      LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Fragment header\n"));

      frag_hdr = (struct ip6_frag_hdr *)p->payload;

      /* Get next header type. */
      nexth = frag_hdr->_nexth;

      /* Fragment Header length. */
      hlen = 8;
      ip_data.current_ip_header_tot_len += hlen;

      /* Make sure this header fits in current pbuf. */
      if (hlen > p->len) {
        LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
          ("IPv6 options header (hlen %"U16_F") does not fit in first pbuf (len %"U16_F"), IPv6 packet dropped.\n",
              hlen, p->len));
        /* free (drop) packet pbufs */
        pbuf_free(p);
        IP6_FRAG_STATS_INC(ip6_frag.lenerr);
        IP6_FRAG_STATS_INC(ip6_frag.drop);
        goto ip6_input_cleanup;
      }

      /* Offset == 0 and more_fragments == 0? */
      if ((frag_hdr->_fragment_offset &
           PP_HTONS(IP6_FRAG_OFFSET_MASK | IP6_FRAG_MORE_FLAG)) == 0) {
        /* This is a 1-fragment packet, usually a packet that we have
         * already reassembled. Skip this header anc continue. */
        pbuf_header(p, -(s16_t)hlen);
      } else {
#if LWIP_IPV6_REASS

        /* reassemble the packet */
        p = ip6_reass(p);
        /* packet not fully reassembled yet? */
        if (p == NULL) {
          goto ip6_input_cleanup;
        }

        /* Returned p point to IPv6 header.
         * Update all our variables and pointers and continue. */
        ip6hdr = (struct ip6_hdr *)p->payload;
        nexth = IP6H_NEXTH(ip6hdr);
        hlen = ip_data.current_ip_header_tot_len = IP6_HLEN;
        pbuf_header(p, -IP6_HLEN);

#else /* LWIP_IPV6_REASS */
        /* free (drop) packet pbufs */
        LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: packet with Fragment header dropped (with LWIP_IPV6_REASS==0)\n"));
        pbuf_free(p);
        IP6_STATS_INC(ip6.opterr);
        IP6_STATS_INC(ip6.drop);
        goto ip6_input_cleanup;
#endif /* LWIP_IPV6_REASS */
      }
      break;
    }
    default:
      goto options_done;
      break;
    }
  }
options_done:

  /* p points to IPv6 header again. */
  pbuf_header_force(p, ip_data.current_ip_header_tot_len);

  /* send to upper layers */
  LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: \n"));
  ip6_debug_print(p);
  LWIP_DEBUGF(IP6_DEBUG, ("ip6_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));

#if LWIP_RAW
  /* raw input did not eat the packet? */
  if (raw_input(p, inp) == 0)
#endif /* LWIP_RAW */
  {
    switch (nexth) {
    case IP6_NEXTH_NONE:
      pbuf_free(p);
      break;
#if LWIP_UDP
    case IP6_NEXTH_UDP:
#if LWIP_UDPLITE
    case IP6_NEXTH_UDPLITE:
#endif /* LWIP_UDPLITE */
      /* Point to payload. */
      pbuf_header(p, -(s16_t)ip_data.current_ip_header_tot_len);
      udp_input(p, inp);
      break;
#endif /* LWIP_UDP */
#if LWIP_TCP
    case IP6_NEXTH_TCP:
      /* Point to payload. */
      pbuf_header(p, -(s16_t)ip_data.current_ip_header_tot_len);
      tcp_input(p, inp);
      break;
#endif /* LWIP_TCP */
#if LWIP_ICMP6
    case IP6_NEXTH_ICMP6:
      /* Point to payload. */
      pbuf_header(p, -(s16_t)ip_data.current_ip_header_tot_len);
      icmp6_input(p, inp);
      break;
#endif /* LWIP_ICMP */
    default:
#if LWIP_ICMP6
      /* send ICMP parameter problem unless it was a multicast or ICMPv6 */
      if ((!ip6_addr_ismulticast(ip6_current_dest_addr())) &&
          (IP6H_NEXTH(ip6hdr) != IP6_NEXTH_ICMP6)) {
        icmp6_param_problem(p, ICMP6_PP_HEADER, ip_data.current_ip_header_tot_len - hlen);
      }
#endif /* LWIP_ICMP */
      LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_input: Unsupported transport protocol %"U16_F"\n", IP6H_NEXTH(ip6hdr)));
      pbuf_free(p);
      IP6_STATS_INC(ip6.proterr);
      IP6_STATS_INC(ip6.drop);
      break;
    }
  }

ip6_input_cleanup:
  ip_data.current_netif = NULL;
  ip_data.current_input_netif = NULL;
  ip_data.current_ip6_header = NULL;
  ip_data.current_ip_header_tot_len = 0;
  ip6_addr_set_zero(ip6_current_src_addr());
  ip6_addr_set_zero(ip6_current_dest_addr());

  return ERR_OK;
}
Ejemplo n.º 5
0
/**
 * Process an input ICMPv6 message. Called by ip6_input.
 *
 * Will generate a reply for echo requests. Other messages are forwarded
 * to nd6_input, or mld6_input.
 *
 * @param p the mld packet, p->payload pointing to the icmpv6 header
 * @param inp the netif on which this packet was received
 */
void
icmp6_input(struct pbuf *p, struct interface *inp)
{
  struct icmp6_hdr *icmp6hdr;
  struct pbuf * r;
  ip6_addr_t * reply_src;

  ICMP6_STATS_INC(icmp6.recv);

  /* Check that ICMPv6 header fits in payload */
  if (p->len < sizeof(struct icmp6_hdr)) {
    /* drop short packets */
    pbuf_free(p);
    ICMP6_STATS_INC(icmp6.lenerr);
    ICMP6_STATS_INC(icmp6.drop);
    return;
  }

  icmp6hdr = (struct icmp6_hdr *)p->payload;

#if LWIP_ICMP6_CHECKSUM_CHECK
  if (ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->tot_len, ip6_current_src_addr(),
                        ip6_current_dest_addr()) != 0) {
    /* Checksum failed */
    pbuf_free(p);
    ICMP6_STATS_INC(icmp6.chkerr);
    ICMP6_STATS_INC(icmp6.drop);
    return;
  }
#endif /* LWIP_ICMP6_CHECKSUM_CHECK */

  switch (icmp6hdr->type) {
  case ICMP6_TYPE_NA: /* Neighbor advertisement */
  case ICMP6_TYPE_NS: /* Neighbor solicitation */
  case ICMP6_TYPE_RA: /* Router advertisement */
  case ICMP6_TYPE_RD: /* Redirect */
  case ICMP6_TYPE_PTB: /* Packet too big */
    nd6_input(p, inp);
    return;
    break;
  case ICMP6_TYPE_RS:
#if LWIP_IPV6_FORWARD
    /* TODO implement router functionality */
#endif
    break;
#if LWIP_IPV6_MLD
  case ICMP6_TYPE_MLQ:
  case ICMP6_TYPE_MLR:
  case ICMP6_TYPE_MLD:
    mld6_input(p, inp);
    return;
    break;
#endif
  case ICMP6_TYPE_EREQ:
#if !LWIP_MULTICAST_PING
    /* multicast destination address? */
    if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
      /* drop */
      pbuf_free(p);
      ICMP6_STATS_INC(icmp6.drop);
      return;
    }
#endif /* LWIP_MULTICAST_PING */

    /* Allocate reply. */
    r = pbuf_alloc(PBUF_IP, p->tot_len, PBUF_RAM);
    if (r == NULL) {
      /* drop */
      pbuf_free(p);
      ICMP6_STATS_INC(icmp6.memerr);
      return;
    }

    /* Copy echo request. */
    if (pbuf_copy(r, p) != ERR_OK) {
      /* drop */
      pbuf_free(p);
      pbuf_free(r);
      ICMP6_STATS_INC(icmp6.err);
      return;
    }

    /* Determine reply source IPv6 address. */
#if LWIP_MULTICAST_PING
    if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
      reply_src = ip6_select_source_address(inp, ip6_current_src_addr());
      if (reply_src == NULL) {
        /* drop */
        pbuf_free(p);
        pbuf_free(r);
        ICMP6_STATS_INC(icmp6.rterr);
        return;
      }
    }
    else
#endif /* LWIP_MULTICAST_PING */
    {
      reply_src = ip6_current_dest_addr();
    }

    /* Set fields in reply. */
    ((struct icmp6_echo_hdr *)(r->payload))->type = ICMP6_TYPE_EREP;
    ((struct icmp6_echo_hdr *)(r->payload))->chksum = 0;
    ((struct icmp6_echo_hdr *)(r->payload))->chksum = ip6_chksum_pseudo(r,
        IP6_NEXTH_ICMP6, r->tot_len, reply_src, ip6_current_src_addr());

    /* Send reply. */
    ICMP6_STATS_INC(icmp6.xmit);
    ip6_output_if(r, reply_src, ip6_current_src_addr(),
        LWIP_ICMP6_HL, 0, IP6_NEXTH_ICMP6, inp);
    pbuf_free(r);

    break;
  default:
    ICMP6_STATS_INC(icmp6.proterr);
    ICMP6_STATS_INC(icmp6.drop);
    break;
  }

  pbuf_free(p);
}