From 591175db7a83984e27ac339771ba421df7607bdb Mon Sep 17 00:00:00 2001
From: Nico Schottelius <nico@nico-notebook.schottelius.org>
Date: Wed, 6 Mar 2019 15:15:46 +0100
Subject: [PATCH] Re-re-re-try to do checkumming based on a meta field

---
 doc/plan.org            |  9 ++++++---
 p4src/checksums.p4      | 24 ++++++++++++------------
 p4src/static-mapping.p4 | 10 ++++++++++
 3 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/doc/plan.org b/doc/plan.org
index 8af1377..dfcb249 100644
--- a/doc/plan.org
+++ b/doc/plan.org
@@ -51,6 +51,7 @@
 |            | * Summary on Slack                                                         |       |
 |            | * 1130 meeting now                                                         |       |
 |            |                                                                            |       |
+|            |                                                                            |       |
 | 2019-03-01 | Feature list / priority list / roadmap clear                               | x     |
 |            | Joining P4 Slack                                                           |       |
 |            |                                                                            |       |
@@ -86,7 +87,7 @@
 |            | - Multiple branches:                                                       |       |
 |            | * Work on checksumming / p4                                                |       |
 |            | * Work on metadata passing / p4                                            |       |
-|            | * Work on static mapping (w/ incorrect checksum)                           |       |
+|            | * Work on static mapping (w/ incorrect checksum) 1:1                       |       |
 |            |                                                                            |       |
 |            |                                                                            |       |
 | 2019-03-08 | NAT46 1:1 table ICMP, ICMPv6 working                                       |       |
@@ -198,6 +199,10 @@ p4@ubuntu:~/master-thesis$
 **** TODO Translate ipv6 --> ipv4 with a (freely programmable) prefix
 ***** TODO Insert prefix into switch
 ***** TODO Implement the calculation
+***** TODO Sketch the flow for session handling for icmp6 w/o packet loss
+      - switch receives icmp6 packet for known prefix
+      - controller needs to create session entry (?)
+
 **** TODO Translate icmp <-> icmp6
 **** TODO Create table entry for mapping v4->v6 [net]
 **** TODO Create table entry for mapping v6->v4 [net]
@@ -539,8 +544,6 @@ performance, security and adaptivity of the solutions.
 - Milestone 1: Stateless NAT64/NAT46 translations in P4
 - Milestone 2: Stateful (dynamic) NAT64/NAT46 translations
 - Milestone 3: Hardware adaption
-
-
 ** Original ideas
 Proposal 1: Automating NAT64 with P4
 
diff --git a/p4src/checksums.p4 b/p4src/checksums.p4
index 231c65c..973031b 100644
--- a/p4src/checksums.p4
+++ b/p4src/checksums.p4
@@ -21,18 +21,18 @@ control MyVerifyChecksum(inout headers hdr, inout metadata meta) {
 
 control MyComputeChecksum(inout headers  hdr, inout metadata meta) {
     apply {
-        // GRRRRR update_checksum_with_payload(meta.do_cksum,
-		// GRRRRR  	{
-        // GRRRRR         hdr.ipv6.src_addr,         /* 128 */
-		// GRRRRR  		hdr.ipv6.dst_addr,         /* 128 */
-        // GRRRRR         16w0,                      /* 16 try implicit cast */
-        // GRRRRR         hdr.ipv6.payload_length,   /* 16 */
-        // GRRRRR         24w0,                      /* 24 0's */
-        // GRRRRR         PROTO_ICMP6                /* 8 */
-        // GRRRRR     },
-        // GRRRRR     hdr.icmp6.checksum,
-        // GRRRRR     HashAlgorithm.csum16
-        // GRRRRR );
+        update_checksum_with_payload(meta.do_cksum == 1,
+		 	{
+                hdr.ipv6.src_addr,         /* 128 */
+		 		hdr.ipv6.dst_addr,         /* 128 */
+                16w0,                      /* 16 try implicit cast */
+                hdr.ipv6.payload_length,   /* 16 */
+                24w0,                      /* 24 0's */
+                PROTO_ICMP6                /* 8 */
+            },
+            hdr.icmp6.checksum,
+            HashAlgorithm.csum16
+        );
     }
 }
 
diff --git a/p4src/static-mapping.p4 b/p4src/static-mapping.p4
index a3c8dd5..f496aa4 100644
--- a/p4src/static-mapping.p4
+++ b/p4src/static-mapping.p4
@@ -66,6 +66,16 @@ control MyIngress(inout headers hdr,
         //meta.cast_length = (bit<32>) hdr.ipv6.payload_length;
     }
 
+    /* this needs SESSIONS!!
+    - icmp6: (src addr, dst addr, ID??, )
+    - tcp: (src port, dst port, dst_addr, src addr)
+    - udp: (src port, dst port, dst_addr, src addr)
+    */
+    action nat64_static(ipv4_addr_t nataddr, ipv6_addr_t nat64_prefix) {
+        hdr.ipv4.dst_addr = hdr.ipv6.dst_addr - nat64_prefix;
+        hdr.ipv4.dst_addr = hdr.ipv6.dst_addr - nat64_prefix;
+    }
+
     /********************** Reply to NDP for US ***********************************/
     table ndp_answer {
         key = {