tcp: move accept init to separate reusable function

Type: refactor

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: I5120eb321e9e2050eb64dca9e2dfb6256ff2b62d

1 files changed, 45 insertions, 0 deletions

diff --git a/src/vnet/tcp/tcp.c b/src/vnet/tcp/tcp.c
index dfcce771654..8a09b565ffa 100644
--- a/src/vnet/tcp/tcp.c
+++ b/src/vnet/tcp/tcp.c
@@ -707,6 +707,51 @@ tcp_connection_init_vars (tcp_connection_t * tc)
   tc->start_ts = tcp_time_now_us (tc->c_thread_index);
 }
 
+void
+tcp_init_w_buffer (tcp_connection_t * tc, vlib_buffer_t * b, u8 is_ip4)
+{
+  tcp_header_t *th = tcp_buffer_hdr (b);
+
+  tc->c_lcl_port = th->dst_port;
+  tc->c_rmt_port = th->src_port;
+  tc->c_is_ip4 = is_ip4;
+
+  if (is_ip4)
+    {
+      ip4_header_t *ip4 = vlib_buffer_get_current (b);
+      tc->c_lcl_ip4.as_u32 = ip4->dst_address.as_u32;
+      tc->c_rmt_ip4.as_u32 = ip4->src_address.as_u32;
+    }
+  else
+    {
+      ip6_header_t *ip6 = vlib_buffer_get_current (b);
+      clib_memcpy_fast (&tc->c_lcl_ip6, &ip6->dst_address,
+			sizeof (ip6_address_t));
+      clib_memcpy_fast (&tc->c_rmt_ip6, &ip6->src_address,
+			sizeof (ip6_address_t));
+    }
+
+  tc->irs = vnet_buffer (b)->tcp.seq_number;
+  tc->rcv_nxt = vnet_buffer (b)->tcp.seq_number + 1;
+  tc->rcv_las = tc->rcv_nxt;
+  tc->sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
+  tc->snd_wl1 = vnet_buffer (b)->tcp.seq_number;
+  tc->snd_wl2 = vnet_buffer (b)->tcp.ack_number;
+
+  /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
+   * segments are used to initialize PAWS. */
+  if (tcp_opts_tstamp (&tc->rcv_opts))
+    {
+      tc->tsval_recent = tc->rcv_opts.tsval;
+      tc->tsval_recent_age = tcp_time_now ();
+    }
+
+  if (tcp_opts_wscale (&tc->rcv_opts))
+    tc->snd_wscale = tc->rcv_opts.wscale;
+
+  tc->snd_wnd = clib_net_to_host_u16 (th->window) << tc->snd_wscale;
+}
+
 static int
 tcp_alloc_custom_local_endpoint (tcp_main_t * tm, ip46_address_t * lcl_addr,
 				 u16 * lcl_port, u8 is_ip4)