lib/librte_gso/gso_tcp4.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2017 Intel Corporation
   3  */
   4
   5 #include "gso_common.h"
   6 #include "gso_tcp4.h"
   7
   8 static void
   9 update_ipv4_tcp_headers(struct rte_mbuf *pkt, uint8_t ipid_delta,
  10                 struct rte_mbuf **segs, uint16_t nb_segs)
  11 {
  12         struct ipv4_hdr *ipv4_hdr;
  13         struct tcp_hdr *tcp_hdr;
  14         uint32_t sent_seq;
  15         uint16_t id, tail_idx, i;
  16         uint16_t l3_offset = pkt->l2_len;
  17         uint16_t l4_offset = l3_offset + pkt->l3_len;
  18
  19         ipv4_hdr = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char*) +
  20                         l3_offset);
  21         tcp_hdr = (struct tcp_hdr *)((char *)ipv4_hdr + pkt->l3_len);
  22         id = rte_be_to_cpu_16(ipv4_hdr->packet_id);
  23         sent_seq = rte_be_to_cpu_32(tcp_hdr->sent_seq);
  24         tail_idx = nb_segs - 1;
  25
  26         for (i = 0; i < nb_segs; i++) {
  27                 update_ipv4_header(segs[i], l3_offset, id);
  28                 update_tcp_header(segs[i], l4_offset, sent_seq, i < tail_idx);
  29                 id += ipid_delta;
  30                 sent_seq += (segs[i]->pkt_len - segs[i]->data_len);
  31         }
  32 }
  33
  34 int
  35 gso_tcp4_segment(struct rte_mbuf *pkt,
  36                 uint16_t gso_size,
  37                 uint8_t ipid_delta,
  38                 struct rte_mempool *direct_pool,
  39                 struct rte_mempool *indirect_pool,
  40                 struct rte_mbuf **pkts_out,
  41                 uint16_t nb_pkts_out)
  42 {
  43         struct ipv4_hdr *ipv4_hdr;
  44         uint16_t pyld_unit_size, hdr_offset;
  45         uint16_t frag_off;
  46         int ret;
  47
  48         /* Don't process the fragmented packet */
  49         ipv4_hdr = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
  50                         pkt->l2_len);
  51         frag_off = rte_be_to_cpu_16(ipv4_hdr->fragment_offset);
  52         if (unlikely(IS_FRAGMENTED(frag_off))) {
  53                 pkts_out[0] = pkt;
  54                 return 1;
  55         }
  56
  57         /* Don't process the packet without data */
  58         hdr_offset = pkt->l2_len + pkt->l3_len + pkt->l4_len;
  59         if (unlikely(hdr_offset >= pkt->pkt_len)) {
  60                 pkts_out[0] = pkt;
  61                 return 1;
  62         }
  63
  64         pyld_unit_size = gso_size - hdr_offset;
  65
  66         /* Segment the payload */
  67         ret = gso_do_segment(pkt, hdr_offset, pyld_unit_size, direct_pool,
  68                         indirect_pool, pkts_out, nb_pkts_out);
  69         if (ret > 1)
  70                 update_ipv4_tcp_headers(pkt, ipid_delta, pkts_out, ret);
  71
  72         return ret;
  73 }