session: add is_migrating flag

Type: fix

Add SESSION_F_IS_MIGRATING flag for session. It is set by the session
layer before poking the transport for migration. It's the transport
responsibility to unset the flag & act apropriatly if RX happens on
a migrating session.

Change-Id: Ie722917f1cf9344d8f041cad4ed8b064fb5853b6
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>

4 files changed, 40 insertions, 49 deletions

diff --git a/src/plugins/quic/quic.c b/src/plugins/quic/quic.c
index 4b2bbefb5f1..291f54608cd 100644
--- a/src/plugins/quic/quic.c
+++ b/src/plugins/quic/quic.c
@@ -60,7 +60,7 @@ quic_ctx_alloc (u32 thread_index)
 static void
 quic_ctx_free (quic_ctx_t * ctx)
 {
-  QUIC_DBG (2, "Free ctx %u", ctx->c_c_index);
+  QUIC_DBG (2, "Free ctx %u %x", ctx->c_thread_index, ctx->c_c_index);
   u32 thread_index = ctx->c_thread_index;
   if (CLIB_DEBUG)
     clib_memset (ctx, 0xfb, sizeof (*ctx));
@@ -139,23 +139,16 @@ quic_sendable_packet_count (session_t * udp_session)
 static quicly_context_t *
 quic_get_quicly_ctx_from_ctx (quic_ctx_t * ctx)
 {
-  app_worker_t *app_wrk;
-  application_t *app;
-  app_wrk = app_worker_get_if_valid (ctx->parent_app_wrk_id);
-  if (!app_wrk)
-    return 0;
-  app = application_get (app_wrk->app_index);
-  return (quicly_context_t *) app->quicly_ctx;
+  return ctx->quicly_ctx;
 }
 
 static quicly_context_t *
 quic_get_quicly_ctx_from_udp (u64 udp_session_handle)
 {
-  session_t *udp_session;
-  application_t *app;
-  udp_session = session_get_from_handle (udp_session_handle);
-  app = application_get (udp_session->opaque);
-  return (quicly_context_t *) app->quicly_ctx;
+  session_t *udp_session = session_get_from_handle (udp_session_handle);
+  quic_ctx_t *ctx =
+    quic_ctx_get (udp_session->opaque, udp_session->thread_index);
+  return ctx->quicly_ctx;
 }
 
 static inline void
@@ -294,7 +287,7 @@ quic_connection_closed (quic_ctx_t * ctx)
       quic_connection_delete (ctx);
       break;
     default:
-      QUIC_DBG (0, "BUG");
+      QUIC_DBG (0, "BUG %d", ctx->conn_state);
       break;
     }
 }
@@ -1079,6 +1072,9 @@ quic_connect_connection (session_endpoint_cfg_t * sep)
   cargs->sep_ext.ns_index = app->ns_index;
 
   quic_store_quicly_ctx (app, 1 /* is client */ );
+  /* Also store it in ctx for convenience
+   * Waiting for crypto_ctx logic */
+  ctx->quicly_ctx = (quicly_context_t *) app->quicly_ctx;
 
   if ((error = vnet_connect (cargs)))
     return error;
@@ -1185,6 +1181,9 @@ quic_start_listen (u32 quic_listen_session_index, transport_endpoint_t * tep)
 
   lctx = quic_ctx_get (lctx_index, 0);
   lctx->flags |= QUIC_F_IS_LISTENER;
+  /* Also store it in ctx for convenience
+   * Waiting for crypto_ctx logic */
+  lctx->quicly_ctx = (quicly_context_t *) app->quicly_ctx;
 
   clib_memcpy (&lctx->c_rmt_ip, &args->sep.peer.ip, sizeof (ip46_address_t));
   clib_memcpy (&lctx->c_lcl_ip, &args->sep.ip, sizeof (ip46_address_t));
@@ -1437,6 +1436,8 @@ quic_receive_connection (void *arg)
 
   /*  Trigger write on this connection if necessary */
   udp_session = session_get_from_handle (new_ctx->udp_session_handle);
+  udp_session->opaque = new_ctx_id;
+  udp_session->flags &= ~SESSION_F_IS_MIGRATING;
   if (svm_fifo_max_dequeue (udp_session->tx_fifo))
     quic_set_udp_tx_evt (udp_session);
 }
@@ -1510,7 +1511,7 @@ quic_udp_session_connected_callback (u32 quic_app_index, u32 ctx_index,
 	    is_fail, thread_index, (ctx) ? ctx_index : ~0);
 
   ctx->udp_session_handle = session_handle (udp_session);
-  udp_session->opaque = ctx->parent_app_id;
+  udp_session->opaque = ctx_index;
 
   /* Init QUIC lib connection
    * Generate required sockaddr & salen */
@@ -1558,31 +1559,19 @@ quic_udp_session_reset_callback (session_t * s)
 static void
 quic_udp_session_migrate_callback (session_t * s, session_handle_t new_sh)
 {
-  /*
-   * TODO we need better way to get the connection from the session
-   * This will become possible once we stop storing the app id in the UDP
-   * session opaque
-   */
-  u32 thread_index = vlib_get_thread_index ();
-  u64 old_session_handle = session_handle (s);
   u32 new_thread = session_thread_from_handle (new_sh);
   quic_ctx_t *ctx;
 
   QUIC_DBG (1, "Session %x migrated to %lx", s->session_index, new_sh);
-  /* *INDENT-OFF* */
-  pool_foreach (ctx, quic_main.ctx_pool[thread_index],
-    ({
-      if (ctx->udp_session_handle == old_session_handle)
-        {
-          /*  Right ctx found, move associated conn */
-          QUIC_DBG (5, "Found right ctx: %x", ctx->c_c_index);
-          ctx->udp_session_handle = new_sh;
-          quic_transfer_connection (ctx->c_c_index, new_thread);
-          return;
-        }
-    }));
-  /* *INDENT-ON* */
-  QUIC_DBG (0, "BUG: Connection to migrate not found");
+  ASSERT (vlib_get_thread_index () == s->thread_index);
+  ctx = quic_ctx_get (s->opaque, s->thread_index);
+  ASSERT (ctx->udp_session_handle == session_handle (s));
+
+  ctx->udp_session_handle = new_sh;
+#if QUIC_DEBUG >= 1
+  s->opaque = 0xfeedface;
+#endif
+  quic_transfer_connection (ctx->c_c_index, new_thread);
 }
 
 int
@@ -1615,7 +1604,11 @@ quic_udp_session_accepted_callback (session_t * udp_session)
   ctx->conn_state = QUIC_CONN_STATE_OPENED;
   ctx->c_flags |= TRANSPORT_CONNECTION_F_NO_LOOKUP;
 
-  udp_session->opaque = ctx->parent_app_id;
+  /* Also store it in ctx for convenience
+   * Waiting for crypto_ctx logic */
+  ctx->quicly_ctx = lctx->quicly_ctx;
+
+  udp_session->opaque = ctx_index;
 
   /* Put this ctx in the "opening" pool */
   pool_get (quic_main.wrk_ctx[ctx->c_thread_index].opening_ctx_pool,
@@ -1847,8 +1840,7 @@ quic_reset_connection (u64 udp_session_handle,
 }
 
 static int
-quic_process_one_rx_packet (u64 udp_session_handle,
-			    quicly_context_t * quicly_ctx, svm_fifo_t * f,
+quic_process_one_rx_packet (u64 udp_session_handle, svm_fifo_t * f,
 			    u32 * fifo_offset, u32 * max_packet, u32 packet_n,
 			    quic_rx_packet_ctx_t * packet_ctx)
 {
@@ -1865,6 +1857,7 @@ quic_process_one_rx_packet (u64 udp_session_handle,
   u32 thread_index = vlib_get_thread_index ();
   u32 *opening_ctx_pool, *ctx_index_ptr;
   u32 cur_deq = svm_fifo_max_dequeue (f) - *fifo_offset;
+  quicly_context_t *quicly_ctx;
 
   if (cur_deq == 0)
     {
@@ -1968,22 +1961,19 @@ static int
 quic_udp_session_rx_callback (session_t * udp_session)
 {
   /*  Read data from UDP rx_fifo and pass it to the quicly conn. */
-  application_t *app;
   quic_ctx_t *ctx = NULL;
   svm_fifo_t *f;
   u32 max_deq;
-  u32 app_index = udp_session->opaque;
   u64 udp_session_handle = session_handle (udp_session);
   int rv = 0;
   u32 thread_index = vlib_get_thread_index ();
   quic_rx_packet_ctx_t packets_ctx[16];
   u32 i, fifo_offset, max_packets;
 
-  if (!(app = application_get_if_valid (app_index)))
+  if (udp_session->flags & SESSION_F_IS_MIGRATING)
     {
-      QUIC_DBG (1, "Got RX on detached app");
-      /*  TODO: close this session, cleanup state? */
-      return 1;
+      QUIC_DBG (3, "RX on migrating udp session");
+      return 0;
     }
 
   while (1)
@@ -1997,10 +1987,8 @@ quic_udp_session_rx_callback (session_t * udp_session)
       fifo_offset = 0;
       max_packets = 16;
       for (i = 0; i < max_packets; i++)
-	quic_process_one_rx_packet (udp_session_handle,
-				    (quicly_context_t *) app->quicly_ctx, f,
-				    &fifo_offset, &max_packets, i,
-				    &packets_ctx[i]);
+	quic_process_one_rx_packet (udp_session_handle, f, &fifo_offset,
+				    &max_packets, i, &packets_ctx[i]);
 
       for (i = 0; i < max_packets; i++)
 	{
diff --git a/src/plugins/quic/quic.h b/src/plugins/quic/quic.h
index d26ad37a01b..dacf07a14ad 100644
--- a/src/plugins/quic/quic.h
+++ b/src/plugins/quic/quic.h
@@ -122,6 +122,7 @@ typedef struct quic_ctx_
   u32 parent_app_wrk_id;
   u32 parent_app_id;
   u8 flags;
+  quicly_context_t *quicly_ctx;
 } quic_ctx_t;
 
 /* Make sure our custom fields don't overlap with the fields we use in
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index be62d929363..f1360226152 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -799,6 +799,7 @@ session_dgram_connect_notify (transport_connection_t * tc,
   new_s->rx_fifo->master_session_index = new_s->session_index;
   new_s->rx_fifo->master_thread_index = new_s->thread_index;
   new_s->session_state = SESSION_STATE_READY;
+  new_s->flags |= SESSION_F_IS_MIGRATING;
   session_lookup_add_connection (tc, session_handle (new_s));
 
   /*
diff --git a/src/vnet/session/session_types.h b/src/vnet/session/session_types.h
index bf45855e264..03f7096c4b8 100644
--- a/src/vnet/session/session_types.h
+++ b/src/vnet/session/session_types.h
@@ -148,6 +148,7 @@ typedef enum session_flags_
   SESSION_F_RX_EVT = 1,
   SESSION_F_PROXY = (1 << 1),
   SESSION_F_CUSTOM_TX = (1 << 2),
+  SESSION_F_IS_MIGRATING = (1 << 3),
 } session_flags_t;
 
 typedef struct session_