From 029f3d2c1c6b04a6cfef17242cb36b304025fe23 Mon Sep 17 00:00:00 2001 From: Matus Fabian Date: Thu, 15 Jun 2017 02:28:50 -0700 Subject: NAT64: Hairpinning (VPP-699) Change-Id: I83a6c277fa211ac2c2ca2d603650c992886af0a7 Signed-off-by: Matus Fabian --- src/vnet/ip/ip4_to_ip6.h | 55 ++++++++++++++++++++++++++++++++---------------- src/vnet/ip/ip6_to_ip4.h | 22 ++++++++++--------- 2 files changed, 49 insertions(+), 28 deletions(-) (limited to 'src/vnet') diff --git a/src/vnet/ip/ip4_to_ip6.h b/src/vnet/ip/ip4_to_ip6.h index dad35230b12..cdd370723f2 100644 --- a/src/vnet/ip/ip4_to_ip6.h +++ b/src/vnet/ip/ip4_to_ip6.h @@ -321,17 +321,9 @@ icmp_to_icmp6 (vlib_buffer_t * p, ip4_to_ip6_set_fn_t fn, void *ctx, //We have an ICMP inside an ICMP //It needs to be translated, but not for error ICMP messages icmp46_header_t *inner_icmp = (icmp46_header_t *) (inner_ip4 + 1); - csum = inner_icmp->checksum; //Only types ICMP4_echo_request and ICMP4_echo_reply are handled by icmp_to_icmp6_header - csum = ip_csum_sub_even (csum, *((u16 *) inner_icmp)); inner_icmp->type = (inner_icmp->type == ICMP4_echo_request) ? ICMP6_echo_request : ICMP6_echo_reply; - csum = ip_csum_add_even (csum, *((u16 *) inner_icmp)); - csum = - ip_csum_add_even (csum, clib_host_to_net_u16 (IP_PROTOCOL_ICMP6)); - csum = - ip_csum_add_even (csum, inner_ip4->length - sizeof (*inner_ip4)); - inner_icmp->checksum = ip_csum_fold (csum); inner_L4_checksum = &inner_icmp->checksum; inner_ip4->protocol = IP_PROTOCOL_ICMP6; } @@ -341,8 +333,6 @@ icmp_to_icmp6 (vlib_buffer_t * p, ip4_to_ip6_set_fn_t fn, void *ctx, os_panic (); } - csum = *inner_L4_checksum; //Initial checksum of the inner L4 header - inner_ip6->ip_version_traffic_class_and_flow_label = clib_host_to_net_u32 ((6 << 28) + (inner_ip4->tos << 20)); inner_ip6->payload_length = @@ -367,14 +357,42 @@ icmp_to_icmp6 (vlib_buffer_t * p, ip4_to_ip6_set_fn_t fn, void *ctx, sizeof (*inner_frag)); } - /* UDP checksum is optional */ - if (csum) + csum = *inner_L4_checksum; + if (inner_ip6->protocol == IP_PROTOCOL_ICMP6) { - csum = ip_csum_add_even (csum, inner_ip6->src_address.as_u64[0]); - csum = ip_csum_add_even (csum, inner_ip6->src_address.as_u64[1]); - csum = ip_csum_add_even (csum, inner_ip6->dst_address.as_u64[0]); - csum = ip_csum_add_even (csum, inner_ip6->dst_address.as_u64[1]); - *inner_L4_checksum = ip_csum_fold (csum); + //Recompute ICMP checksum + icmp46_header_t *inner_icmp = (icmp46_header_t *) (inner_ip4 + 1); + + inner_icmp->checksum = 0; + csum = ip_csum_with_carry (0, inner_ip6->payload_length); + csum = + ip_csum_with_carry (csum, + clib_host_to_net_u16 (inner_ip6->protocol)); + csum = ip_csum_with_carry (csum, inner_ip6->src_address.as_u64[0]); + csum = ip_csum_with_carry (csum, inner_ip6->src_address.as_u64[1]); + csum = ip_csum_with_carry (csum, inner_ip6->dst_address.as_u64[0]); + csum = ip_csum_with_carry (csum, inner_ip6->dst_address.as_u64[1]); + csum = + ip_incremental_checksum (csum, inner_icmp, + clib_net_to_host_u16 + (inner_ip6->payload_length)); + inner_icmp->checksum = ~ip_csum_fold (csum); + } + else + { + /* UDP checksum is optional */ + if (csum) + { + csum = + ip_csum_add_even (csum, inner_ip6->src_address.as_u64[0]); + csum = + ip_csum_add_even (csum, inner_ip6->src_address.as_u64[1]); + csum = + ip_csum_add_even (csum, inner_ip6->dst_address.as_u64[0]); + csum = + ip_csum_add_even (csum, inner_ip6->dst_address.as_u64[1]); + *inner_L4_checksum = ip_csum_fold (csum); + } } } else @@ -518,6 +536,7 @@ ip4_to_ip6_tcp_udp (vlib_buffer_t * p, ip4_to_ip6_set_fn_t fn, void *ctx) csum = ip_csum_sub_even (*checksum, ip4->src_address.as_u32); csum = ip_csum_sub_even (csum, ip4->dst_address.as_u32); + *checksum = ip_csum_fold (csum); // Deal with fragmented packets if (PREDICT_FALSE (ip4->flags_and_fragment_offset & @@ -558,7 +577,7 @@ ip4_to_ip6_tcp_udp (vlib_buffer_t * p, ip4_to_ip6_set_fn_t fn, void *ctx) if ((rv = fn (ip4, ip6, ctx)) != 0) return rv; - csum = ip_csum_add_even (csum, ip6->src_address.as_u64[0]); + csum = ip_csum_add_even (*checksum, ip6->src_address.as_u64[0]); csum = ip_csum_add_even (csum, ip6->src_address.as_u64[1]); csum = ip_csum_add_even (csum, ip6->dst_address.as_u64[0]); csum = ip_csum_add_even (csum, ip6->dst_address.as_u64[1]); diff --git a/src/vnet/ip/ip6_to_ip4.h b/src/vnet/ip/ip6_to_ip4.h index 92f73ba165d..7a0d534959c 100644 --- a/src/vnet/ip/ip6_to_ip4.h +++ b/src/vnet/ip/ip6_to_ip4.h @@ -314,13 +314,9 @@ icmp6_to_icmp (vlib_buffer_t * p, ip6_to_ip4_set_fn_t fn, void *ctx, else if (inner_protocol == IP_PROTOCOL_ICMP6) { icmp46_header_t *inner_icmp = (icmp46_header_t *) inner_l4; - csum = inner_icmp->checksum; - csum = ip_csum_sub_even (csum, *((u16 *) inner_icmp)); //It cannot be of a different type as ip6_icmp_to_icmp6_in_place succeeded inner_icmp->type = (inner_icmp->type == ICMP6_echo_request) ? ICMP4_echo_request : ICMP4_echo_reply; - csum = ip_csum_add_even (csum, *((u16 *) inner_icmp)); - inner_icmp->checksum = ip_csum_fold (csum); inner_protocol = IP_PROTOCOL_ICMP; //Will be copied to ip6 later inner_L4_checksum = &inner_icmp->checksum; } @@ -334,6 +330,7 @@ icmp6_to_icmp (vlib_buffer_t * p, ip6_to_ip4_set_fn_t fn, void *ctx, csum = ip_csum_sub_even (csum, inner_ip6->src_address.as_u64[1]); csum = ip_csum_sub_even (csum, inner_ip6->dst_address.as_u64[0]); csum = ip_csum_sub_even (csum, inner_ip6->dst_address.as_u64[1]); + *inner_L4_checksum = ip_csum_fold (csum); if ((rv = inner_fn (inner_ip6, inner_ip4, inner_ctx)) != 0) return rv; @@ -353,19 +350,23 @@ icmp6_to_icmp (vlib_buffer_t * p, ip6_to_ip4_set_fn_t fn, void *ctx, if (inner_ip4->protocol == IP_PROTOCOL_ICMP) { - //Remove remainings of the pseudo-header in the csum - csum = - ip_csum_sub_even (csum, clib_host_to_net_u16 (IP_PROTOCOL_ICMP6)); + //Recompute ICMP checksum + icmp46_header_t *inner_icmp = (icmp46_header_t *) inner_l4; + inner_icmp->checksum = 0; csum = - ip_csum_sub_even (csum, inner_ip4->length - sizeof (*inner_ip4)); + ip_incremental_checksum (0, inner_icmp, + clib_net_to_host_u16 (inner_ip4->length) + - sizeof (*inner_ip4)); + inner_icmp->checksum = ~ip_csum_fold (csum); } else { //Update to new pseudo-header + csum = *inner_L4_checksum; csum = ip_csum_add_even (csum, inner_ip4->src_address.as_u32); csum = ip_csum_add_even (csum, inner_ip4->dst_address.as_u32); + *inner_L4_checksum = ip_csum_fold (csum); } - *inner_L4_checksum = ip_csum_fold (csum); //Move up icmp header ip4 = (ip4_header_t *) u8_ptr_add (inner_l4, -2 * sizeof (*ip4) - 8); @@ -512,6 +513,7 @@ ip6_to_ip4_tcp_udp (vlib_buffer_t * p, ip6_to_ip4_set_fn_t fn, void *ctx, csum = ip_csum_sub_even (csum, ip6->src_address.as_u64[1]); csum = ip_csum_sub_even (csum, ip6->dst_address.as_u64[0]); csum = ip_csum_sub_even (csum, ip6->dst_address.as_u64[1]); + *checksum = ip_csum_fold (csum); no_csum: ip4 = (ip4_header_t *) u8_ptr_add (ip6, l4_offset - sizeof (*ip4)); @@ -552,7 +554,7 @@ no_csum: } else { - csum = ip_csum_add_even (csum, ip4->dst_address.as_u32); + csum = ip_csum_add_even (*checksum, ip4->dst_address.as_u32); csum = ip_csum_add_even (csum, ip4->src_address.as_u32); *checksum = ip_csum_fold (csum); } -- cgit 1.2.3-korg