示例#1
0
/**
 * IPv6 fragmentation.
 *
 * This function implements the fragmentation of IPv6 packets.
 *
 * @param pkt_in
 *   The input packet.
 * @param pkts_out
 *   Array storing the output fragments.
 * @param mtu_size
 *   Size in bytes of the Maximum Transfer Unit (MTU) for the outgoing IPv6
 *   datagrams. This value includes the size of the IPv6 header.
 * @param pool_direct
 *   MBUF pool used for allocating direct buffers for the output fragments.
 * @param pool_indirect
 *   MBUF pool used for allocating indirect buffers for the output fragments.
 * @return
 *   Upon successful completion - number of output fragments placed
 *   in the pkts_out array.
 *   Otherwise - (-1) * <errno>.
 */
int32_t
rte_ipv6_fragment_packet(struct rte_mbuf *pkt_in,
	struct rte_mbuf **pkts_out,
	uint16_t nb_pkts_out,
	uint16_t mtu_size,
	struct rte_mempool *pool_direct,
	struct rte_mempool *pool_indirect)
{
	struct rte_mbuf *in_seg = NULL;
	struct ipv6_hdr *in_hdr;
	uint32_t out_pkt_pos, in_seg_data_pos;
	uint32_t more_in_segs;
	uint16_t fragment_offset, frag_size;

	frag_size = (uint16_t)(mtu_size - sizeof(struct ipv6_hdr));

	/* Fragment size should be a multiple of 8. */
	IP_FRAG_ASSERT((frag_size & IPV6_HDR_FO_MASK) == 0);

	/* Check that pkts_out is big enough to hold all fragments */
	if (unlikely (frag_size * nb_pkts_out <
	    (uint16_t)(pkt_in->pkt.pkt_len - sizeof (struct ipv6_hdr))))
		return (-EINVAL);

	in_hdr = (struct ipv6_hdr *) pkt_in->pkt.data;

	in_seg = pkt_in;
	in_seg_data_pos = sizeof(struct ipv6_hdr);
	out_pkt_pos = 0;
	fragment_offset = 0;

	more_in_segs = 1;
	while (likely(more_in_segs)) {
		struct rte_mbuf *out_pkt = NULL, *out_seg_prev = NULL;
		uint32_t more_out_segs;
		struct ipv6_hdr *out_hdr;

		/* Allocate direct buffer */
		out_pkt = rte_pktmbuf_alloc(pool_direct);
		if (unlikely(out_pkt == NULL)) {
			__free_fragments(pkts_out, out_pkt_pos);
			return (-ENOMEM);
		}

		/* Reserve space for the IP header that will be built later */
		out_pkt->pkt.data_len = sizeof(struct ipv6_hdr) + sizeof(struct ipv6_extension_fragment);
		out_pkt->pkt.pkt_len  = sizeof(struct ipv6_hdr) + sizeof(struct ipv6_extension_fragment);

		out_seg_prev = out_pkt;
		more_out_segs = 1;
		while (likely(more_out_segs && more_in_segs)) {
			struct rte_mbuf *out_seg = NULL;
			uint32_t len;

			/* Allocate indirect buffer */
			out_seg = rte_pktmbuf_alloc(pool_indirect);
			if (unlikely(out_seg == NULL)) {
				rte_pktmbuf_free(out_pkt);
				__free_fragments(pkts_out, out_pkt_pos);
				return (-ENOMEM);
			}
			out_seg_prev->pkt.next = out_seg;
			out_seg_prev = out_seg;

			/* Prepare indirect buffer */
			rte_pktmbuf_attach(out_seg, in_seg);
			len = mtu_size - out_pkt->pkt.pkt_len;
			if (len > (in_seg->pkt.data_len - in_seg_data_pos)) {
				len = in_seg->pkt.data_len - in_seg_data_pos;
			}
			out_seg->pkt.data = (char *) in_seg->pkt.data + (uint16_t) in_seg_data_pos;
			out_seg->pkt.data_len = (uint16_t)len;
			out_pkt->pkt.pkt_len = (uint16_t)(len +
			    out_pkt->pkt.pkt_len);
			out_pkt->pkt.nb_segs += 1;
			in_seg_data_pos += len;

			/* Current output packet (i.e. fragment) done ? */
			if (unlikely(out_pkt->pkt.pkt_len >= mtu_size)) {
				more_out_segs = 0;
			}

			/* Current input segment done ? */
			if (unlikely(in_seg_data_pos == in_seg->pkt.data_len)) {
				in_seg = in_seg->pkt.next;
				in_seg_data_pos = 0;

				if (unlikely(in_seg == NULL)) {
					more_in_segs = 0;
				}
			}
		}

		/* Build the IP header */

		out_hdr = (struct ipv6_hdr *) out_pkt->pkt.data;

		__fill_ipv6hdr_frag(out_hdr, in_hdr,
		    (uint16_t) out_pkt->pkt.pkt_len - sizeof(struct ipv6_hdr),
		    fragment_offset, more_in_segs);

		fragment_offset = (uint16_t)(fragment_offset +
		    out_pkt->pkt.pkt_len - sizeof(struct ipv6_hdr)
			- sizeof(struct ipv6_extension_fragment));

		/* Write the fragment to the output list */
		pkts_out[out_pkt_pos] = out_pkt;
		out_pkt_pos ++;
	}

	return (out_pkt_pos);
}
示例#2
0
int32_t rte_ipv6_fragment_packet_flat(struct rte_mbuf *pkt_in,
                                      struct rte_mbuf **pkts_out,
                                      uint16_t nb_pkts_out, uint16_t mtu_size,
                                      struct rte_mempool *pool_direct,
                                      struct rte_mbuf* (*alloc_func)(struct rte_mempool *))
{
  struct rte_mbuf *in_seg = NULL;
  struct ipv6_hdr *in_hdr;
  uint32_t out_pkt_pos, in_seg_data_pos;
  uint32_t more_in_segs;
  uint16_t fragment_offset, frag_size;
#if 0
  if (mtu_size >= MTU_SIZE){
    return -ENOTSUP;
  }
#endif  
  frag_size = (uint16_t)(mtu_size - sizeof(struct ipv6_hdr));

  /* Fragment size should be a multiple of 8. */
  IP_FRAG_ASSERT((frag_size & IPV6_HDR_FO_MASK) == 0);

  /* Check that pkts_out is big enough to hold all fragments */
  if (unlikely (frag_size * nb_pkts_out <
                (uint16_t)(pkt_in->pkt_len - sizeof (struct ipv6_hdr))))
    return (-EINVAL);

  in_hdr = rte_pktmbuf_mtod(pkt_in, struct ipv6_hdr *);

  in_seg = pkt_in;
  in_seg_data_pos = sizeof(struct ipv6_hdr);
  out_pkt_pos = 0;
  fragment_offset = 0;

  more_in_segs = 1;
  while (likely(more_in_segs)) {
    struct rte_mbuf *out_pkt = NULL;
    uint32_t more_out_segs;
    struct ipv6_hdr *out_hdr;

    /* Allocate direct buffer */
    out_pkt = (*alloc_func)(pool_direct);
    if (unlikely(out_pkt == NULL)) {
      __free_fragments(pkts_out, out_pkt_pos);
      return (-ENOMEM);
    }

    /* Reserve space for the IP header that will be built later */
    out_pkt->data_len = sizeof(struct ipv6_hdr) + sizeof(struct ipv6_extension_fragment);
    out_pkt->pkt_len  = sizeof(struct ipv6_hdr) + sizeof(struct ipv6_extension_fragment);

    more_out_segs = 1;
    while (likely(more_out_segs && more_in_segs)) {
      uint32_t len;
      unsigned char *out_segptr, *in_segptr;
      
      len = mtu_size - out_pkt->pkt_len;
      if (len > (in_seg->data_len - in_seg_data_pos)) {
        len = in_seg->data_len - in_seg_data_pos;
      }

       out_segptr = rte_pktmbuf_mtod(out_pkt, unsigned char *);
      in_segptr = rte_pktmbuf_mtod(in_seg, unsigned char *);
      in_segptr += in_seg_data_pos;
      out_segptr += out_pkt->data_len;
      
      memcpy(out_segptr, in_segptr, len);
            
      out_pkt->data_len = (uint16_t)(len + out_pkt->data_len);
      out_pkt->pkt_len = (uint16_t)(len +
                                    out_pkt->pkt_len);
      
      in_seg_data_pos += len;

      /* Current output packet (i.e. fragment) done ? */
      if (unlikely(out_pkt->pkt_len >= mtu_size)) {
        more_out_segs = 0;
      }

      /* Current input segment done ? */
      if (unlikely(in_seg_data_pos == in_seg->data_len)) {
        in_seg = in_seg->next;
        in_seg_data_pos = 0;

        if (unlikely(in_seg == NULL)) {
          more_in_segs = 0;
        }
      }
    }

    /* Build the IP header */

    out_hdr = rte_pktmbuf_mtod(out_pkt, struct ipv6_hdr *);

    __fill_ipv6hdr_frag(out_hdr, in_hdr,
                        (uint16_t) out_pkt->pkt_len - sizeof(struct ipv6_hdr),
                        fragment_offset, more_in_segs);

    fragment_offset = (uint16_t)(fragment_offset +
                                 out_pkt->pkt_len - sizeof(struct ipv6_hdr)
                                 - sizeof(struct ipv6_extension_fragment));
    
    /* Write the fragment to the output list */
    pkts_out[out_pkt_pos] = out_pkt;
    out_pkt_pos ++;
  }
  
  return (out_pkt_pos);

  return 0;
}