[dpdk-dev] [PATCH v2] ip_frag: fix fragmenting ipv4 packet with header option
Ananyev, Konstantin
konstantin.ananyev at intel.com
Tue Apr 6 15:53:09 CEST 2021
>
> From: Pu Xu <583493798 at qq.com>
>
> When fragmenting ipv4 packet, the data offset should be calculated through
> the ihl field in ip header rather than using sizeof(struct rte_ipv4_hdr).
>
> Fixes: 4c38e5532a07 ("ip_frag: refactor IPv4 fragmentation into a proper library")
>
> Signed-off-by: Pu Xu <583493798 at qq.com>
> ---
> lib/librte_ip_frag/rte_ipv4_fragmentation.c | 34 +++++++++++++--------
> 1 file changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/lib/librte_ip_frag/rte_ipv4_fragmentation.c b/lib/librte_ip_frag/rte_ipv4_fragmentation.c
> index e9de335ae..2e7739d02 100644
> --- a/lib/librte_ip_frag/rte_ipv4_fragmentation.c
> +++ b/lib/librte_ip_frag/rte_ipv4_fragmentation.c
> @@ -23,10 +23,10 @@
> #define IPV4_HDR_FO_ALIGN (1 << RTE_IPV4_HDR_FO_SHIFT)
>
> static inline void __fill_ipv4hdr_frag(struct rte_ipv4_hdr *dst,
> - const struct rte_ipv4_hdr *src, uint16_t len, uint16_t fofs,
> - uint16_t dofs, uint32_t mf)
> + const struct rte_ipv4_hdr *src, uint16_t header_len,
> + uint16_t len, uint16_t fofs, uint16_t dofs, uint32_t mf)
> {
> - rte_memcpy(dst, src, sizeof(*dst));
> + rte_memcpy(dst, src, header_len);
> fofs = (uint16_t)(fofs + (dofs >> RTE_IPV4_HDR_FO_SHIFT));
> fofs = (uint16_t)(fofs | mf << RTE_IPV4_HDR_MF_SHIFT);
> dst->fragment_offset = rte_cpu_to_be_16(fofs);
> @@ -74,7 +74,7 @@ rte_ipv4_fragment_packet(struct rte_mbuf *pkt_in,
> struct rte_ipv4_hdr *in_hdr;
> uint32_t out_pkt_pos, in_seg_data_pos;
> uint32_t more_in_segs;
> - uint16_t fragment_offset, flag_offset, frag_size;
> + uint16_t fragment_offset, flag_offset, frag_size, header_len;
> uint16_t frag_bytes_remaining;
>
> /*
> @@ -86,14 +86,22 @@ rte_ipv4_fragment_packet(struct rte_mbuf *pkt_in,
> unlikely(mtu_size < RTE_ETHER_MIN_MTU))
> return -EINVAL;
>
> + in_hdr = rte_pktmbuf_mtod(pkt_in, struct rte_ipv4_hdr *);
> + header_len = (in_hdr->version_ihl & RTE_IPV4_HDR_IHL_MASK) *
> + RTE_IPV4_IHL_MULTIPLIER;
> +
> + /* Check IP header length */
> + if (unlikely(pkt_in->data_len < header_len) ||
> + unlikely(mtu_size < header_len))
> + return -EINVAL;
> +
> /*
> * Ensure the IP payload length of all fragments is aligned to a
> * multiple of 8 bytes as per RFC791 section 2.3.
> */
> - frag_size = RTE_ALIGN_FLOOR((mtu_size - sizeof(struct rte_ipv4_hdr)),
> + frag_size = RTE_ALIGN_FLOOR((mtu_size - header_len),
> IPV4_HDR_FO_ALIGN);
>
> - in_hdr = rte_pktmbuf_mtod(pkt_in, struct rte_ipv4_hdr *);
> flag_offset = rte_cpu_to_be_16(in_hdr->fragment_offset);
>
> /* If Don't Fragment flag is set */
> @@ -102,11 +110,11 @@ rte_ipv4_fragment_packet(struct rte_mbuf *pkt_in,
>
> /* 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 rte_ipv4_hdr))))
> + (uint16_t)(pkt_in->pkt_len - header_len)))
> return -EINVAL;
>
> in_seg = pkt_in;
> - in_seg_data_pos = sizeof(struct rte_ipv4_hdr);
> + in_seg_data_pos = header_len;
> out_pkt_pos = 0;
> fragment_offset = 0;
>
> @@ -124,8 +132,8 @@ rte_ipv4_fragment_packet(struct rte_mbuf *pkt_in,
> }
>
> /* Reserve space for the IP header that will be built later */
> - out_pkt->data_len = sizeof(struct rte_ipv4_hdr);
> - out_pkt->pkt_len = sizeof(struct rte_ipv4_hdr);
> + out_pkt->data_len = header_len;
> + out_pkt->pkt_len = header_len;
> frag_bytes_remaining = frag_size;
>
> out_seg_prev = out_pkt;
> @@ -176,14 +184,14 @@ rte_ipv4_fragment_packet(struct rte_mbuf *pkt_in,
>
> out_hdr = rte_pktmbuf_mtod(out_pkt, struct rte_ipv4_hdr *);
>
> - __fill_ipv4hdr_frag(out_hdr, in_hdr,
> + __fill_ipv4hdr_frag(out_hdr, in_hdr, header_len,
> (uint16_t)out_pkt->pkt_len,
> flag_offset, fragment_offset, more_in_segs);
>
> fragment_offset = (uint16_t)(fragment_offset +
> - out_pkt->pkt_len - sizeof(struct rte_ipv4_hdr));
> + out_pkt->pkt_len - header_len);
>
> - out_pkt->l3_len = sizeof(struct rte_ipv4_hdr);
> + out_pkt->l3_len = header_len;
>
> /* Write the fragment to the output list */
> pkts_out[out_pkt_pos] = out_pkt;
> --
Acked-by: Konstantin Ananyev <konstantin.ananyev at intel.com>
> 2.17.0
More information about the dev
mailing list