/**
 * Same as ip6_output_if() but 'src' address is not replaced by netif address
 * when it is 'any'.
 */
err_t
ip6_output_if_src(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
             u8_t hl, u8_t tc,
             u8_t nexth, struct netif *netif)
{
  struct ip6_hdr *ip6hdr;
  ip6_addr_t dest_addr;

  LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);

  /* Should the IPv6 header be generated or is it already included in p? */
  if (dest != IP_HDRINCL) {
    /* generate IPv6 header */
    if (pbuf_header(p, IP6_HLEN)) {
      LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_output: not enough room for IPv6 header in pbuf\n"));
      IP6_STATS_INC(ip6.err);
      return ERR_BUF;
    }

    ip6hdr = (struct ip6_hdr *)p->payload;
    LWIP_ASSERT("check that first pbuf can hold struct ip6_hdr",
               (p->len >= sizeof(struct ip6_hdr)));

    IP6H_HOPLIM_SET(ip6hdr, hl);
    IP6H_NEXTH_SET(ip6hdr, nexth);

    /* dest cannot be NULL here */
    ip6_addr_copy(ip6hdr->dest, *dest);

    IP6H_VTCFL_SET(ip6hdr, 6, tc, 0);
    IP6H_PLEN_SET(ip6hdr, p->tot_len - IP6_HLEN);

    if (src == NULL) {
      src = IP6_ADDR_ANY6;
    }
    /* src cannot be NULL here */
    ip6_addr_copy(ip6hdr->src, *src);

  } else {
    /* IP header already included in p */
    ip6hdr = (struct ip6_hdr *)p->payload;
    ip6_addr_copy(dest_addr, ip6hdr->dest);
    dest = &dest_addr;
  }

  IP6_STATS_INC(ip6.xmit);

  LWIP_DEBUGF(IP6_DEBUG, ("ip6_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
  ip6_debug_print(p);

#if ENABLE_LOOPBACK
  {
    int i;
#if !LWIP_HAVE_LOOPIF
    if (ip6_addr_isloopback(dest)) {
      return netif_loop_output(netif, p);
    }
#endif /* !LWIP_HAVE_LOOPIF */
    for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
      if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
          ip6_addr_cmp(dest, netif_ip6_addr(netif, i))) {
        /* Packet to self, enqueue it for loopback */
        LWIP_DEBUGF(IP6_DEBUG, ("netif_loop_output()\n"));
        return netif_loop_output(netif, p);
      }
    }
  }
#endif /* ENABLE_LOOPBACK */
#if LWIP_IPV6_FRAG
  /* don't fragment if interface has mtu set to 0 [loopif] */
  if (netif->mtu && (p->tot_len > nd6_get_destination_mtu(dest, netif))) {
    return ip6_frag(p, netif, dest);
  }
#endif /* LWIP_IPV6_FRAG */

  LWIP_DEBUGF(IP6_DEBUG, ("netif->output_ip6()\n"));
  return netif->output_ip6(netif, p, dest);
}
Beispiel #2
0
/**
 * Sends an IPv6 packet on a network interface. This function constructs
 * the IPv6 header. If the source IPv6 address is NULL, the IPv6 "ANY" address is
 * used as source (usually during network startup). If the source IPv6 address it
 * IP6_ADDR_ANY, the most appropriate IPv6 address of the outgoing network
 * interface is filled in as source address. If the destination IPv6 address is
 * IP_HDRINCL, p is assumed to already include an IPv6 header and p->payload points
 * to it instead of the data.
 *
 * @param p the packet to send (p->payload points to the data, e.g. next
            protocol header; if dest == IP_HDRINCL, p already includes an
            IPv6 header and p->payload points to that IPv6 header)
 * @param src the source IPv6 address to send from (if src == IP6_ADDR_ANY, an
 *         IP address of the netif is selected and used as source address.
 *         if src == NULL, IP6_ADDR_ANY is used as source)
 * @param dest the destination IPv6 address to send the packet to
 * @param hl the Hop Limit value to be set in the IPv6 header
 * @param tc the Traffic Class value to be set in the IPv6 header
 * @param nexth the Next Header to be set in the IPv6 header
 * @param netif the netif on which to send this packet
 * @return ERR_OK if the packet was sent OK
 *         ERR_BUF if p doesn't have enough space for IPv6/LINK headers
 *         returns errors returned by netif->output
 */
err_t
ip6_output_if(struct pbuf *p, ip6_addr_t *src, ip6_addr_t *dest,
              u8_t hl, u8_t tc,
              u8_t nexth, struct netif *netif)
{
    struct ip6_hdr *ip6hdr;
    ip6_addr_t dest_addr;

    /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
       gets altered as the packet is passed down the stack */
    LWIP_ASSERT("p->ref == 1", p->ref == 1);

    /* Should the IPv6 header be generated or is it already included in p? */
    if (dest != IP_HDRINCL) {
        /* generate IPv6 header */
        if (pbuf_header(p, IP6_HLEN)) {
            LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_output: not enough room for IPv6 header in pbuf\n"));
            IP6_STATS_INC(ip6.err);
            return ERR_BUF;
        }

        ip6hdr = (struct ip6_hdr *)p->payload;
        LWIP_ASSERT("check that first pbuf can hold struct ip6_hdr",
                    (p->len >= sizeof(struct ip6_hdr)));

        IP6H_HOPLIM_SET(ip6hdr, hl);
        IP6H_NEXTH_SET(ip6hdr, nexth);

        /* dest cannot be NULL here */
        ip6_addr_copy(ip6hdr->dest, *dest);

        IP6H_VTCFL_SET(ip6hdr, 6, tc, 0);
        IP6H_PLEN_SET(ip6hdr, p->tot_len - IP6_HLEN);

        if (src == NULL) {
            src = IP6_ADDR_ANY;
        }
        else if (ip6_addr_isany(src)) {
            src = ip6_select_source_address(netif, dest);
            if ((src == NULL) || ip6_addr_isany(src)) {
                /* No appropriate source address was found for this packet. */
                LWIP_DEBUGF(IP6_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip6_output: No suitable source address for packet.\n"));
                IP6_STATS_INC(ip6.rterr);
                return ERR_RTE;
            }
        }
        /* src cannot be NULL here */
        ip6_addr_copy(ip6hdr->src, *src);

    } else {
        /* IP header already included in p */
        ip6hdr = (struct ip6_hdr *)p->payload;
        ip6_addr_copy(dest_addr, ip6hdr->dest);
        dest = &dest_addr;
    }

    IP6_STATS_INC(ip6.xmit);

    LWIP_DEBUGF(IP6_DEBUG, ("ip6_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
    ip6_debug_print(p);

#if ENABLE_LOOPBACK
    /* TODO implement loopback for v6
    if (ip6_addr_cmp(dest, netif_ip6_addr(0))) {
      return netif_loop_output(netif, p, dest);
    }*/
#endif /* ENABLE_LOOPBACK */
#if LWIP_IPV6_FRAG
    /* don't fragment if interface has mtu set to 0 [loopif] */
    if (netif->mtu && (p->tot_len > nd6_get_destination_mtu(dest, netif))) {
        return ip6_frag(p, netif, dest);
    }
#endif /* LWIP_IPV6_FRAG */

    LWIP_DEBUGF(IP6_DEBUG, ("netif->output_ip6()"));
    return netif->output_ip6(netif, p, dest);
}