From 27d822e88e61fa74f30a9239fc5bb24daaae7f59 Mon Sep 17 00:00:00 2001 From: Akhil Goyal Date: Mon, 15 Jan 2018 18:12:12 +0530 Subject: [PATCH] examples/ipsec-secgw: update incremental checksum When TTL is decremented or ecn is updated in IP header before forwarding the packet, checksum needs to be updated. In this patch an incremental checksum is added for ipv4 case. Signed-off-by: Akhil Goyal Acked-by: Radu Nicolau --- examples/ipsec-secgw/ipip.h | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/examples/ipsec-secgw/ipip.h b/examples/ipsec-secgw/ipip.h index fb6a6fa459..13b8455c3e 100644 --- a/examples/ipsec-secgw/ipip.h +++ b/examples/ipsec-secgw/ipip.h @@ -27,6 +27,10 @@ ipip_outbound(struct rte_mbuf *m, uint32_t offset, uint32_t is_ipv6, if (inip4->ip_v == IPVERSION) { /* XXX This should be done by the forwarding engine instead */ inip4->ip_ttl -= 1; + if (inip4->ip_sum >= rte_cpu_to_be_16(0xffff - 0x100)) + inip4->ip_sum += rte_cpu_to_be_16(0x100) + 1; + else + inip4->ip_sum += rte_cpu_to_be_16(0x100); ds_ecn = inip4->ip_tos; } else { inip6 = (struct ip6_hdr *)inip4; @@ -95,8 +99,17 @@ ip6ip_outbound(struct rte_mbuf *m, uint32_t offset, static inline void ip4_ecn_setup(struct ip *ip4) { - if (ip4->ip_tos & IPTOS_ECN_MASK) + if (ip4->ip_tos & IPTOS_ECN_MASK) { + unsigned long sum; + uint8_t old; + + old = ip4->ip_tos; ip4->ip_tos |= IPTOS_ECN_CE; + sum = old + (~(*(uint8_t *)&ip4->ip_tos) & 0xff); + sum += rte_be_to_cpu_16(ip4->ip_sum); + sum = (sum & 0xffff) + (sum >> 16); + ip4->ip_sum = rte_cpu_to_be_16(sum + (sum >> 16)); + } } static inline void @@ -140,6 +153,10 @@ ipip_inbound(struct rte_mbuf *m, uint32_t offset) ip4_ecn_setup(inip4); /* XXX This should be done by the forwarding engine instead */ inip4->ip_ttl -= 1; + if (inip4->ip_sum >= rte_cpu_to_be_16(0xffff - 0x100)) + inip4->ip_sum += rte_cpu_to_be_16(0x100) + 1; + else + inip4->ip_sum += rte_cpu_to_be_16(0x100); m->packet_type &= ~RTE_PTYPE_L4_MASK; if (inip4->ip_p == IPPROTO_UDP) m->packet_type |= RTE_PTYPE_L4_UDP; -- 2.20.1