From 162ef20072d4283cd1afc2106f051fa95f5001db Mon Sep 17 00:00:00 2001
From: Nico Schottelius <nico@nico-notebook.schottelius.org>
Date: Sat, 23 Mar 2019 14:39:56 +0100
Subject: [PATCH] Checksum the newly parsed fields

---
 doc/plan.org            |  1 +
 p4src/checksums.p4      | 28 +++++++++++++++++++++++++++-
 p4src/headers.p4        |  4 +++-
 p4src/static-mapping.p4 |  1 +
 4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/doc/plan.org b/doc/plan.org
index 9da3f65..0623ccf 100644
--- a/doc/plan.org
+++ b/doc/plan.org
@@ -121,6 +121,7 @@
 |            |                                                                            |       |
 | 2019-03-23 | Parsing down to link layer option                                          |       |
 |            | Parsing on wrong field detected by unset fields in wireshark               |       |
+|            | Correcting parser->leads to incorrect checksum                             |       |
 |            |                                                                            |       |
 |            |                                                                            |       |
 | 2019-03-28 | Meet Laurent #4                                                            |       |
diff --git a/p4src/checksums.p4 b/p4src/checksums.p4
index 183380d..9e05953 100644
--- a/p4src/checksums.p4
+++ b/p4src/checksums.p4
@@ -21,7 +21,7 @@ control MyVerifyChecksum(inout headers hdr, inout metadata meta) {
 
 control MyComputeChecksum(inout headers  hdr, inout metadata meta) {
     apply {
-        update_checksum_with_payload(meta.do_cksum == 1,
+        update_checksum_with_payload(meta.task == TASK_CHECKSUM_ICMP6,
 		 	{
                 hdr.ipv6.src_addr,         /* 128 */
 		 		hdr.ipv6.dst_addr,         /* 128 */
@@ -34,6 +34,32 @@ control MyComputeChecksum(inout headers  hdr, inout metadata meta) {
             hdr.icmp6.checksum,
             HashAlgorithm.csum16
         );
+
+        /* checksumming for icmp6_na_ns_option */
+        update_checksum_with_payload(meta.task == TASK_CHECKSUM_ICMP6_NA,
+		 	{
+                hdr.ipv6.src_addr,         /* 128 */
+		 		hdr.ipv6.dst_addr,         /* 128 */
+                meta.cast_length,          /* 32 */
+                24w0,                      /* 24 0's */
+                PROTO_ICMP6,               /* 8 */
+                hdr.icmp6.type,            /* 8 */
+                hdr.icmp6.code,            /* 8 */
+
+                hdr.icmp6_na_ns.router,
+                hdr.icmp6_na_ns.solicitated,
+                hdr.icmp6_na_ns.override,
+                hdr.icmp6_na_ns.reserved,
+                hdr.icmp6_na_ns.target_addr,
+
+                hdr.icmp6_option_link_layer_addr.type,
+                hdr.icmp6_option_link_layer_addr.ll_length,
+                hdr.icmp6_option_link_layer_addr.mac_addr
+            },
+            hdr.icmp6.checksum,
+            HashAlgorithm.csum16
+        );
+
     }
 }
 
diff --git a/p4src/headers.p4 b/p4src/headers.p4
index 3c06323..a60ceb0 100644
--- a/p4src/headers.p4
+++ b/p4src/headers.p4
@@ -43,6 +43,9 @@ const task_t TASK_ICMP6_NS       = 1;
 const task_t TASK_ICMP6_GENERAL  = 2;
 const task_t TASK_DEBUG          = 3;
 const task_t TASK_ICMP6_REPLY    = 4;
+const task_t TASK_CHECKSUM_ICMP6    = 5; /* data plane */
+const task_t TASK_CHECKSUM_ICMP6_NA = 6; /* data plane */
+
 
 /* 48+48+16 = 112 */
 header ethernet_t {
@@ -165,7 +168,6 @@ struct metadata {
     task_t task;
     bit<16> tcp_length;
     bit<32> cast_length;
-    bit<1> do_cksum;
 }
 
 #endif
\ No newline at end of file
diff --git a/p4src/static-mapping.p4 b/p4src/static-mapping.p4
index 1205745..993353f 100644
--- a/p4src/static-mapping.p4
+++ b/p4src/static-mapping.p4
@@ -67,6 +67,7 @@ control MyIngress(inout headers hdr,
         hdr.icmp6_option_link_layer_addr.ll_length = 1; /* 1* 64 bit */
         hdr.icmp6_option_link_layer_addr.mac_addr = mac_addr;
 
+
         /* version1: rebuilding packet */
         /*
         truncate((bit<32>)(112 + 320 + 32)/8);