examples/ipsec-secgw: fix packet length

for packets smaller then 64B some NICs reports pkt_len=64B.
As ipsec-secgw (and librte_ipsec) relies on pkt_len value to determine
payload length, that causes problems for small packets.
To fix the issue, check that pkt_len matches values in IPv4/IPv6 header
and re-adjust pkt_len if necessary.

Fixes: 906257e965b7 ("examples/ipsec-secgw: support IPv6")
Fixes: d299106e8e31 ("examples/ipsec-secgw: add IPsec sample application")
Cc: stable@dpdk.org
Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Acked-by: Akhil Goyal <akhil.goyal@nxp.com>

diff --git a/examples/ipsec-secgw/ipsec-secgw.c b/examples/ipsec-secgw/ipsec-secgw.c
index 3911e6a..33c4389 100644 (file)
--- a/examples/ipsec-secgw/ipsec-secgw.c
+++ b/examples/ipsec-secgw/ipsec-secgw.c
@@ -230,34 +230,65 @@ static struct rte_eth_conf port_conf = {
 
 static struct socket_ctx socket_ctx[NB_SOCKETS];
 
+static inline void
+adjust_ipv4_pktlen(struct rte_mbuf *m, const struct rte_ipv4_hdr *iph,
+       uint32_t l2_len)
+{
+       uint32_t plen, trim;
+
+       plen = rte_be_to_cpu_16(iph->total_length) + l2_len;
+       if (plen < m->pkt_len) {
+               trim = m->pkt_len - plen;
+               rte_pktmbuf_trim(m, trim);
+       }
+}
+
+static inline void
+adjust_ipv6_pktlen(struct rte_mbuf *m, const struct rte_ipv6_hdr *iph,
+       uint32_t l2_len)
+{
+       uint32_t plen, trim;
+
+       plen = rte_be_to_cpu_16(iph->payload_len) + sizeof(*iph) + l2_len;
+       if (plen < m->pkt_len) {
+               trim = m->pkt_len - plen;
+               rte_pktmbuf_trim(m, trim);
+       }
+}
+
 static inline void
 prepare_one_packet(struct rte_mbuf *pkt, struct ipsec_traffic *t)
 {
-       uint8_t *nlp;
-       struct rte_ether_hdr *eth;
+       const struct rte_ether_hdr *eth;
+       const struct rte_ipv4_hdr *iph4;
+       const struct rte_ipv6_hdr *iph6;
 
-       eth = rte_pktmbuf_mtod(pkt, struct rte_ether_hdr *);
+       eth = rte_pktmbuf_mtod(pkt, const struct rte_ether_hdr *);
        if (eth->ether_type == rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4)) {
-               nlp = (uint8_t *)rte_pktmbuf_adj(pkt, RTE_ETHER_HDR_LEN);
-               nlp = RTE_PTR_ADD(nlp, offsetof(struct ip, ip_p));
-               if (*nlp == IPPROTO_ESP)
+
+               iph4 = (const struct rte_ipv4_hdr *)rte_pktmbuf_adj(pkt,
+                       RTE_ETHER_HDR_LEN);
+               adjust_ipv4_pktlen(pkt, iph4, 0);
+
+               if (iph4->next_proto_id == IPPROTO_ESP)
                        t->ipsec.pkts[(t->ipsec.num)++] = pkt;
                else {
-                       t->ip4.data[t->ip4.num] = nlp;
+                       t->ip4.data[t->ip4.num] = &iph4->next_proto_id;
                        t->ip4.pkts[(t->ip4.num)++] = pkt;
                }
                pkt->l2_len = 0;
-               pkt->l3_len = sizeof(struct ip);
+               pkt->l3_len = sizeof(*iph4);
        } else if (eth->ether_type == rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV6)) {
                int next_proto;
                size_t l3len, ext_len;
-               struct rte_ipv6_hdr *v6h;
                uint8_t *p;
 
                /* get protocol type */
-               v6h = (struct rte_ipv6_hdr *)rte_pktmbuf_adj(pkt,
+               iph6 = (const struct rte_ipv6_hdr *)rte_pktmbuf_adj(pkt,
                        RTE_ETHER_HDR_LEN);
-               next_proto = v6h->proto;
+               adjust_ipv6_pktlen(pkt, iph6, 0);
+
+               next_proto = iph6->proto;
 
                /* determine l3 header size up to ESP extension */
                l3len = sizeof(struct ip6_hdr);
@@ -276,9 +307,7 @@ prepare_one_packet(struct rte_mbuf *pkt, struct ipsec_traffic *t)
                if (next_proto == IPPROTO_ESP)
                        t->ipsec.pkts[(t->ipsec.num)++] = pkt;
                else {
-                       t->ip6.data[t->ip6.num] = rte_pktmbuf_mtod_offset(pkt,
-                               uint8_t *,
-                               offsetof(struct rte_ipv6_hdr, proto));
+                       t->ip6.data[t->ip6.num] = &iph6->proto;
                        t->ip6.pkts[(t->ip6.num)++] = pkt;
                }
                pkt->l2_len = 0;