commit 2089c69efbc4ae5c64cab8a5418187b21478987a
author Tarun Gupta <tarungup@cisco.com> Mon Nov 04 16:35:59 2019 -0800
committer Florin Coras <florin.coras@gmail.com> Wed Nov 06 00:42:41 2019 +0000
tree eefd1469bf359d3e176e8ae352ec78c395dbc4aa
parent ead1e536d66d83b546528c32e2112085a97c8e13

tcp: IPv6 flow label support

Type:feature

For cases when proxy is in use IPv6 flow label received in origin pkt needs to be added
to ipv6 header of outgoing pkts from proxy to original destination and vice versa.

Signed-off-by: Tarun Gupta <tarungup@cisco.com>
Change-Id: I143f7e67237c0f865333078628a016b50ad5e630
Signed-off-by: Tarun Gupta <tarungup@cisco.com>

src/vnet/tcp/tcp.h

diff --git a/src/vnet/tcp/tcp.h b/src/vnet/tcp/tcp.h
index 7309e0a..4b0a0dd 100644
--- a/src/vnet/tcp/tcp.h
+++ b/src/vnet/tcp/tcp.h
@@ -435,6 +435,7 @@
   u32 last_fib_check;	/**< Last time we checked fib route for peer */
   u16 mss;		/**< Our max seg size that includes options */
   u32 timestamp_delta;	/**< Offset for timestamp */
+  u32 ipv6_flow_label;	/**< flow label for ipv6 header */
 } tcp_connection_t;
 
 /* *INDENT-OFF* */

src/vnet/tcp/tcp_output.c

diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c
index 71e9d7b..c7e9792 100644
--- a/src/vnet/tcp/tcp_output.c
+++ b/src/vnet/tcp/tcp_output.c
@@ -842,8 +842,10 @@
       int bogus = ~0;
       ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
 	      0x60);
-      ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
-				  &pkt_ih6->src_address, IP_PROTOCOL_TCP);
+      ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
+					 &pkt_ih6->src_address,
+					 IP_PROTOCOL_TCP,
+					 tc->ipv6_flow_label);
       th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
       ASSERT (!bogus);
     }
@@ -909,8 +911,9 @@
       ip6_header_t *ih;
       int bogus = ~0;
 
-      ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
-				 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
+      ih = vlib_buffer_push_ip6_custom (vm, b, &tc->c_lcl_ip6,
+					&tc->c_rmt_ip6, IP_PROTOCOL_TCP,
+					tc->ipv6_flow_label);
       th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
       ASSERT (!bogus);
     }
@@ -2278,8 +2281,9 @@
     ih0 = vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
 				IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
   else
-    ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
-				IP_PROTOCOL_TCP);
+    ih0 =
+      vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
+				   IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
 
 }