http: support client connect

Type: feature

Signed-off-by: Filip Tehlar <ftehlar@cisco.com>
Change-Id: I0738c0aefb41ab6c0ff717cfccd1df75ddb481fa

2 files changed, 448 insertions, 53 deletions

diff --git a/src/plugins/http/http.c b/src/plugins/http/http.c
index 279a46a7fc6..752ca47a691 100644
--- a/src/plugins/http/http.c
+++ b/src/plugins/http/http.c
@@ -20,6 +20,15 @@
 static http_main_t http_main;
 
 #define HTTP_FIFO_THRESH (16 << 10)
+#define CONTENT_LEN_STR	 "Content-Length: "
+
+/* HTTP state machine result */
+typedef enum http_sm_result_t_
+{
+  HTTP_SM_STOP = 0,
+  HTTP_SM_CONTINUE = 1,
+  HTTP_SM_ERROR = -1,
+} http_sm_result_t;
 
 const char *http_status_code_str[] = {
 #define _(c, s, str) str,
@@ -147,14 +156,14 @@ http_ts_accept_callback (session_t *ts)
   hc_index = http_conn_alloc_w_thread (ts->thread_index);
   hc = http_conn_get_w_thread (hc_index, ts->thread_index);
   clib_memcpy_fast (hc, lhc, sizeof (*lhc));
-  hc->c_thread_index = vlib_get_thread_index ();
+  hc->c_thread_index = ts->thread_index;
   hc->h_hc_index = hc_index;
 
   hc->h_tc_session_handle = session_handle (ts);
   hc->c_flags |= TRANSPORT_CONNECTION_F_NO_LOOKUP;
 
   hc->state = HTTP_CONN_STATE_ESTABLISHED;
-  hc->req_state = HTTP_REQ_STATE_WAIT_METHOD;
+  hc->http_state = HTTP_STATE_WAIT_METHOD;
 
   ts->session_state = SESSION_STATE_READY;
   ts->opaque = hc_index;
@@ -163,7 +172,6 @@ http_ts_accept_callback (session_t *ts)
    * Alloc session and initialize
    */
   as = session_alloc (hc->c_thread_index);
-  as->session_state = SESSION_STATE_CREATED;
   hc->c_s_index = as->session_index;
 
   as->app_wrk_index = hc->h_pa_wrk_index;
@@ -212,10 +220,66 @@ http_ts_accept_callback (session_t *ts)
 }
 
 static int
-http_ts_connected_callback (u32 http_app_index, u32 hc_index, session_t *ts,
+http_ts_connected_callback (u32 http_app_index, u32 ho_hc_index, session_t *ts,
 			    session_error_t err)
 {
-  clib_warning ("not supported");
+  u32 new_hc_index;
+  session_t *as;
+  http_conn_t *hc, *ho_hc;
+  app_worker_t *app_wrk;
+  int rv;
+
+  if (err)
+    {
+      clib_warning ("ERROR: %d", err);
+      return 0;
+    }
+
+  new_hc_index = http_conn_alloc_w_thread (ts->thread_index);
+  hc = http_conn_get_w_thread (new_hc_index, ts->thread_index);
+  ho_hc = http_conn_get_w_thread (ho_hc_index, 0);
+
+  ASSERT (ho_hc->state == HTTP_CONN_STATE_CONNECTING);
+
+  clib_memcpy_fast (hc, ho_hc, sizeof (*hc));
+
+  hc->c_thread_index = ts->thread_index;
+  hc->h_tc_session_handle = session_handle (ts);
+  hc->c_c_index = new_hc_index;
+  hc->c_flags |= TRANSPORT_CONNECTION_F_NO_LOOKUP;
+  hc->state = HTTP_CONN_STATE_ESTABLISHED;
+  hc->http_state = HTTP_STATE_WAIT_APP;
+
+  ts->session_state = SESSION_STATE_READY;
+  ts->opaque = new_hc_index;
+
+  /* allocate app session and initialize */
+
+  as = session_alloc (hc->c_thread_index);
+  hc->c_s_index = as->session_index;
+  as->connection_index = hc->c_c_index;
+  as->app_wrk_index = hc->h_pa_wrk_index;
+  as->session_state = SESSION_STATE_READY;
+  as->session_type = session_type_from_proto_and_ip (
+    TRANSPORT_PROTO_HTTP, session_type_is_ip4 (ts->session_type));
+
+  app_wrk = app_worker_get (hc->h_pa_wrk_index);
+  if (!app_wrk)
+    {
+      clib_warning ("no app worker");
+      return -1;
+    }
+
+  if ((rv = app_worker_init_connected (app_wrk, as)))
+    {
+      HTTP_DBG (1, "failed to allocate fifos");
+      session_free (as);
+      return rv;
+    }
+  app_worker_connect_notify (app_wrk, as, err, hc->h_pa_app_api_ctx);
+  hc->h_pa_session_handle = session_handle (as);
+  http_conn_timer_start (hc);
+
   return 0;
 }
 
@@ -243,7 +307,7 @@ http_ts_reset_callback (session_t *ts)
 
   hc->state = HTTP_CONN_STATE_CLOSED;
   http_buffer_free (&hc->tx_buf);
-  hc->req_state = HTTP_REQ_STATE_WAIT_METHOD;
+  hc->http_state = HTTP_STATE_WAIT_METHOD;
   session_transport_reset_notify (&hc->connection);
 
   http_disconnect_transport (hc);
@@ -269,6 +333,10 @@ static const char *http_response_template = "HTTP/1.1 200 OK\r\n"
 					    "Content-Type: %s\r\n"
 					    "Content-Length: %lu\r\n\r\n";
 
+static const char *http_request_template = "GET %s HTTP/1.1\r\n"
+					   "User-Agent: VPP HTTP client\r\n"
+					   "Accept: */*\r\n";
+
 static u32
 send_data (http_conn_t *hc, u8 *data, u32 length, u32 offset)
 {
@@ -309,7 +377,7 @@ send_error (http_conn_t *hc, http_status_code_t ec)
 }
 
 static int
-read_request (http_conn_t *hc)
+read_http_message (http_conn_t *hc)
 {
   u32 max_deq, cursize;
   session_t *ts;
@@ -337,7 +405,7 @@ static int
 v_find_index (u8 *vec, u32 offset, char *str)
 {
   int start_index = offset;
-  u32 slen = (u32) strnlen_s_inline (str, 8);
+  u32 slen = (u32) strnlen_s_inline (str, 16);
   u32 vlen = vec_len (vec);
 
   ASSERT (slen > 0);
@@ -357,8 +425,8 @@ v_find_index (u8 *vec, u32 offset, char *str)
 /**
  * waiting for request method from peer - parse request method and data
  */
-static int
-state_wait_method (http_conn_t *hc, transport_send_params_t *sp)
+static http_sm_result_t
+state_srv_wait_method (http_conn_t *hc, transport_send_params_t *sp)
 {
   http_status_code_t ec;
   app_worker_t *app_wrk;
@@ -368,11 +436,11 @@ state_wait_method (http_conn_t *hc, transport_send_params_t *sp)
   u32 len;
   u8 *buf;
 
-  rv = read_request (hc);
+  rv = read_http_message (hc);
 
   /* Nothing yet, wait for data or timer expire */
   if (rv)
-    return 0;
+    return HTTP_SM_STOP;
 
   if (vec_len (hc->rx_buf) < 8)
     {
@@ -425,16 +493,16 @@ state_wait_method (http_conn_t *hc, transport_send_params_t *sp)
       /* This should not happen as we only handle 1 request per session,
        * and fifo is allocated, but going forward we should consider
        * rescheduling */
-      return -1;
+      return HTTP_SM_ERROR;
     }
 
   vec_free (hc->rx_buf);
-  hc->req_state = HTTP_REQ_STATE_WAIT_APP;
+  hc->http_state = HTTP_STATE_WAIT_APP;
 
   app_wrk = app_worker_get_if_valid (as->app_wrk_index);
   app_worker_lock_and_send_event (app_wrk, as, SESSION_IO_EVT_RX);
 
-  return 0;
+  return HTTP_SM_STOP;
 
 error:
 
@@ -442,14 +510,14 @@ error:
   session_transport_closing_notify (&hc->connection);
   http_disconnect_transport (hc);
 
-  return -1;
+  return HTTP_SM_ERROR;
 }
 
 /**
  * waiting for data from app
  */
-static int
-state_wait_app (http_conn_t *hc, transport_send_params_t *sp)
+static http_sm_result_t
+state_srv_wait_app (http_conn_t *hc, transport_send_params_t *sp)
 {
   http_main_t *hm = &http_main;
   http_status_code_t ec;
@@ -509,26 +577,25 @@ state_wait_app (http_conn_t *hc, transport_send_params_t *sp)
   vec_free (header);
 
   /* Start sending the actual data */
-  hc->req_state = HTTP_REQ_STATE_SEND_MORE_DATA;
+  hc->http_state = HTTP_STATE_IO_MORE_DATA;
 
   ASSERT (sp->max_burst_size >= offset);
   sp->max_burst_size -= offset;
 
-  return 1;
+  return HTTP_SM_CONTINUE;
 
 error:
 
   send_error (hc, ec);
-  hc->req_state = HTTP_REQ_STATE_WAIT_METHOD;
+  hc->http_state = HTTP_STATE_WAIT_METHOD;
   session_transport_closing_notify (&hc->connection);
   http_disconnect_transport (hc);
 
-  /* stop state machine processing */
-  return 0;
+  return HTTP_SM_STOP;
 }
 
-static int
-state_send_more_data (http_conn_t *hc, transport_send_params_t *sp)
+static http_sm_result_t
+state_srv_send_more_data (http_conn_t *hc, transport_send_params_t *sp)
 {
   u32 max_send = 64 << 10, n_segs;
   http_buffer_t *hb = &hc->tx_buf;
@@ -569,52 +636,331 @@ state_send_more_data (http_conn_t *hc, transport_send_params_t *sp)
       if (sent && svm_fifo_set_event (ts->tx_fifo))
 	session_send_io_evt_to_thread (ts->tx_fifo, SESSION_IO_EVT_TX_FLUSH);
 
-      /* Finished transaction, back to HTTP_REQ_STATE_WAIT_METHOD */
-      hc->req_state = HTTP_REQ_STATE_WAIT_METHOD;
+      /* Finished transaction, back to HTTP_STATE_WAIT_METHOD */
+      hc->http_state = HTTP_STATE_WAIT_METHOD;
       http_buffer_free (&hc->tx_buf);
     }
 
+  return HTTP_SM_STOP;
+}
+
+static int
+parse_http_header (http_conn_t *hc, int *content_length)
+{
+  unformat_input_t input;
+  int i, len;
+  u8 *line;
+
+  if ((i = v_find_index (hc->rx_buf, hc->rx_buf_offset, "200 OK") < 0))
+    {
+      clib_warning ("bad response code");
+      return -1;
+    }
+
+  i = v_find_index (hc->rx_buf, hc->rx_buf_offset, CONTENT_LEN_STR);
+  if (i < 0)
+    {
+      clib_warning ("cannot find '%s' in the header!", CONTENT_LEN_STR);
+      return -1;
+    }
+
+  hc->rx_buf_offset = i;
+
+  i = v_find_index (hc->rx_buf, hc->rx_buf_offset, "\n");
+  if (i < 0)
+    {
+      clib_warning ("end of line missing; incomplete data");
+      return -1;
+    }
+
+  len = i - hc->rx_buf_offset;
+  line = vec_new (u8, len);
+  clib_memcpy (line, hc->rx_buf + hc->rx_buf_offset, len);
+
+  unformat_init_vector (&input, line);
+  if (!unformat (&input, CONTENT_LEN_STR "%d", content_length))
+    {
+      clib_warning ("failed to unformat content length!");
+      return -1;
+    }
+  unformat_free (&input);
+
+  /* skip rest of the header */
+  hc->rx_buf_offset += len;
+  i = v_find_index (hc->rx_buf, hc->rx_buf_offset, "<html>");
+  if (i < 0)
+    {
+      clib_warning ("<html> tag not found");
+      return -1;
+    }
+  hc->rx_buf_offset = i;
+
   return 0;
 }
 
-typedef int (*http_sm_handler) (http_conn_t *, transport_send_params_t *sp);
+static int
+state_cln_wait_method (http_conn_t *hc, transport_send_params_t *sp)
+{
+  session_t *as;
+  http_msg_t msg;
+  app_worker_t *app_wrk;
+  int rv, content_length;
+
+  rv = read_http_message (hc);
+  if (rv)
+    return HTTP_SM_STOP;
+
+  msg.type = HTTP_MSG_REPLY;
+  msg.content_type = HTTP_CONTENT_TEXT_HTML;
+  msg.code = HTTP_STATUS_OK;
+  msg.data.type = HTTP_MSG_DATA_INLINE;
+  msg.data.len = 0;
+
+  rv = parse_http_header (hc, &content_length);
+  if (rv)
+    {
+      clib_warning ("failed to parse http reply");
+      session_transport_closing_notify (&hc->connection);
+      http_disconnect_transport (hc);
+      return -1;
+    }
+
+  msg.data.len = content_length;
+  u32 dlen = vec_len (hc->rx_buf) - hc->rx_buf_offset;
+  as = session_get_from_handle (hc->h_pa_session_handle);
+  svm_fifo_seg_t segs[2] = { { (u8 *) &msg, sizeof (msg) },
+			     { &hc->rx_buf[hc->rx_buf_offset], dlen } };
+
+  rv = svm_fifo_enqueue_segments (as->rx_fifo, segs, 2, 0 /* allow partial */);
+  if (rv < 0)
+    {
+      clib_warning ("error enqueue");
+      return HTTP_SM_ERROR;
+    }
+  hc->rx_buf_offset += dlen;
+  hc->http_state = HTTP_STATE_IO_MORE_DATA;
+  hc->to_recv = content_length - dlen;
+
+  if (hc->rx_buf_offset == vec_len (hc->rx_buf))
+    {
+      vec_reset_length (hc->rx_buf);
+      hc->rx_buf_offset = 0;
+    }
+
+  if (hc->to_recv == 0)
+    {
+      hc->rx_buf_offset = 0;
+      vec_reset_length (hc->rx_buf);
+      hc->http_state = HTTP_STATE_WAIT_APP;
+    }
+
+  app_wrk = app_worker_get_if_valid (as->app_wrk_index);
+  app_worker_lock_and_send_event (app_wrk, as, SESSION_IO_EVT_RX);
+  return HTTP_SM_STOP;
+}
+
+static int
+cln_drain_rx_buf (http_conn_t *hc, session_t *ts, session_t *as)
+{
+  app_worker_t *app_wrk;
+  u32 max_enq, n_enq, dlen = vec_len (hc->rx_buf) - hc->rx_buf_offset;
+  int rv;
+
+  max_enq = svm_fifo_max_enqueue (as->rx_fifo);
+  n_enq = clib_min (max_enq, dlen);
+  rv = svm_fifo_enqueue (as->rx_fifo, n_enq, &hc->rx_buf[hc->rx_buf_offset]);
+  if (rv < 0)
+    {
+      clib_warning ("enqueue failed");
+      return -1;
+    }
+
+  hc->rx_buf_offset += rv;
+
+  if (hc->rx_buf_offset >= vec_len (hc->rx_buf))
+    {
+      vec_reset_length (hc->rx_buf);
+      hc->rx_buf_offset = 0;
+    }
+
+  app_wrk = app_worker_get_if_valid (as->app_wrk_index);
+  ASSERT (app_wrk);
+
+  app_worker_lock_and_send_event (app_wrk, as, SESSION_IO_EVT_RX);
+  return 1;
+}
+
+static http_sm_result_t
+state_cln_recv_more_data (http_conn_t *hc, transport_send_params_t *sp)
+{
+  session_t *as;
+  u32 max_deq;
+  session_t *ts;
+  int n_read, rv;
+
+  as = session_get_from_handle (hc->h_pa_session_handle);
+  ts = session_get_from_handle (hc->h_tc_session_handle);
+
+  u32 dlen = vec_len (hc->rx_buf) - hc->rx_buf_offset;
+  if (dlen)
+    {
+      rv = cln_drain_rx_buf (hc, ts, as);
+      if (rv < 0)
+	{
+	  clib_warning ("drain rx error!");
+	  return HTTP_SM_ERROR;
+	}
+      goto maybe_reschedule;
+    }
+
+  if (hc->to_recv == 0)
+    {
+      ASSERT (vec_len (hc->rx_buf) == 0);
+      ASSERT (hc->rx_buf_offset == 0);
+      hc->http_state = HTTP_STATE_WAIT_APP;
+      return HTTP_SM_STOP;
+    }
+
+  max_deq = svm_fifo_max_dequeue (ts->rx_fifo);
+  if (max_deq == 0)
+    return HTTP_SM_STOP;
+
+  ASSERT (vec_len (hc->rx_buf) == 0);
+  ASSERT (hc->rx_buf_offset == 0);
+
+  vec_validate (hc->rx_buf, max_deq - 1);
+  n_read = svm_fifo_dequeue (ts->rx_fifo, max_deq, hc->rx_buf);
+  ASSERT (n_read == max_deq);
+
+  if (svm_fifo_is_empty (ts->rx_fifo))
+    svm_fifo_unset_event (ts->rx_fifo);
+
+  hc->to_recv -= n_read;
+  vec_set_len (hc->rx_buf, max_deq);
+
+maybe_reschedule:
+  if (hc->rx_buf_offset < vec_len (hc->rx_buf) ||
+      svm_fifo_max_dequeue_cons (ts->rx_fifo))
+    {
+      if (svm_fifo_set_event (ts->rx_fifo))
+	session_send_io_evt_to_thread (ts->rx_fifo, SESSION_IO_EVT_BUILTIN_RX);
+    }
+  return HTTP_SM_CONTINUE;
+}
+
+static http_sm_result_t
+state_cln_wait_app (http_conn_t *hc, transport_send_params_t *sp)
+{
+  session_t *as;
+  http_msg_t msg;
+  http_status_code_t ec;
+  u8 *buf = 0, *request;
+  u32 offset;
+  int rv;
+
+  as = session_get_from_handle (hc->h_pa_session_handle);
+  rv = svm_fifo_dequeue (as->tx_fifo, sizeof (msg), (u8 *) &msg);
+  ASSERT (rv == sizeof (msg));
+  if (msg.type != HTTP_MSG_REQUEST || msg.data.type > HTTP_MSG_DATA_PTR)
+    {
+      clib_warning ("unexpected msg type from app %u", msg.type);
+      ec = HTTP_STATUS_INTERNAL_ERROR;
+      goto error;
+    }
+
+  vec_validate (buf, msg.data.len - 1);
+  rv = svm_fifo_dequeue (as->tx_fifo, msg.data.len, buf);
+  ASSERT (rv == msg.data.len);
 
-static http_sm_handler req_state_funcs[HTTP_REQ_N_STATES] = {
+  request = format (0, http_request_template, buf);
+  offset = send_data (hc, request, vec_len (request), 0);
+  if (offset != vec_len (request))
+    {
+      clib_warning ("sending request failed!");
+      ec = HTTP_STATUS_INTERNAL_ERROR;
+      goto error;
+    }
+
+  hc->http_state = HTTP_STATE_WAIT_METHOD;
+
+  vec_free (buf);
+  vec_free (request);
+
+  return HTTP_SM_CONTINUE;
+
+error:
+  send_error (hc, ec);
+  session_transport_closing_notify (&hc->connection);
+  http_disconnect_transport (hc);
+  return HTTP_SM_STOP;
+}
+
+typedef http_sm_result_t (*http_sm_handler) (http_conn_t *,
+					     transport_send_params_t *sp);
+
+static http_sm_handler srv_state_funcs[HTTP_N_STATES] = {
   /* Waiting for GET, POST, etc. */
-  state_wait_method,
+  state_srv_wait_method,
   /* Wait for data from app */
-  state_wait_app,
+  state_srv_wait_app,
   /* Send more data */
-  state_send_more_data,
+  state_srv_send_more_data,
+};
+
+static http_sm_handler cln_state_funcs[HTTP_N_STATES] = {
+  /* wait for reply */
+  state_cln_wait_method,
+  /* wait for data from app */
+  state_cln_wait_app,
+  /* receive more data */
+  state_cln_recv_more_data,
 };
 
 static void
 http_req_run_state_machine (http_conn_t *hc, transport_send_params_t *sp)
 {
-  int rv;
-
+  http_sm_result_t res;
+  http_sm_handler *state_fn =
+    hc->is_client ? cln_state_funcs : srv_state_funcs;
   do
     {
-      rv = req_state_funcs[hc->req_state](hc, sp);
-      if (rv < 0)
+      res = state_fn[hc->http_state](hc, sp);
+      if (res == HTTP_SM_ERROR)
 	return;
     }
-  while (rv);
+  while (res == HTTP_SM_CONTINUE);
 
   /* Reset the session expiration timer */
   http_conn_timer_update (hc);
 }
 
 static int
-http_ts_rx_callback (session_t *ts)
+http_ts_server_rx_callback (session_t *ts, http_conn_t *hc)
 {
-  http_conn_t *hc;
+  if (hc->http_state != HTTP_STATE_WAIT_METHOD)
+    {
+      clib_warning ("tcp data in req state %u", hc->http_state);
+      return 0;
+    }
 
-  hc = http_conn_get_w_thread (ts->opaque, ts->thread_index);
+  http_req_run_state_machine (hc, 0);
 
-  if (hc->req_state != HTTP_REQ_STATE_WAIT_METHOD)
+  if (hc->state == HTTP_CONN_STATE_TRANSPORT_CLOSED)
     {
-      clib_warning ("tcp data in req state %u", hc->req_state);
+      if (!svm_fifo_max_dequeue_cons (ts->rx_fifo))
+	session_transport_closing_notify (&hc->connection);
+    }
+  return 0;
+}
+
+static int
+http_ts_client_rx_callback (session_t *ts, http_conn_t *hc)
+{
+  if (hc->http_state != HTTP_STATE_WAIT_METHOD &&
+      hc->http_state != HTTP_STATE_IO_MORE_DATA)
+    {
+      clib_warning ("http in unexpected state %d (ts %d)", hc->http_state,
+		    ts->session_index);
       return 0;
     }
 
@@ -628,6 +974,17 @@ http_ts_rx_callback (session_t *ts)
   return 0;
 }
 
+static int
+http_ts_rx_callback (session_t *ts)
+{
+  http_conn_t *hc;
+
+  hc = http_conn_get_w_thread (ts->opaque, ts->thread_index);
+  if (hc->is_client)
+    return http_ts_client_rx_callback (ts, hc);
+  return http_ts_server_rx_callback (ts, hc);
+}
+
 int
 http_ts_builtin_tx_callback (session_t *ts)
 {
@@ -738,7 +1095,34 @@ http_transport_enable (vlib_main_t *vm, u8 is_en)
 static int
 http_transport_connect (transport_endpoint_cfg_t *tep)
 {
-  return -1;
+  vnet_connect_args_t _cargs, *cargs = &_cargs;
+  http_main_t *hm = &http_main;
+  session_endpoint_cfg_t *sep = (session_endpoint_cfg_t *) tep;
+  application_t *app;
+  http_conn_t *hc;
+  int error;
+  u32 hc_index;
+  app_worker_t *app_wrk = app_worker_get (sep->app_wrk_index);
+
+  clib_memset (cargs, 0, sizeof (*cargs));
+  clib_memcpy (&cargs->sep_ext, sep, sizeof (session_endpoint_cfg_t));
+  cargs->sep.transport_proto = TRANSPORT_PROTO_TCP;
+  cargs->app_index = hm->app_index;
+  app = application_get (app_wrk->app_index);
+  cargs->sep_ext.ns_index = app->ns_index;
+
+  hc_index = http_conn_alloc_w_thread (0 /* ts->thread_index */);
+  hc = http_conn_get_w_thread (hc_index, 0);
+  hc->h_pa_wrk_index = sep->app_wrk_index;
+  hc->h_pa_app_api_ctx = sep->opaque;
+  hc->is_client = 1;
+  hc->state = HTTP_CONN_STATE_CONNECTING;
+  cargs->api_context = hc_index;
+
+  if ((error = vnet_connect (cargs)))
+    return error;
+
+  return 0;
 }
 
 static u32
@@ -819,6 +1203,13 @@ http_transport_close (u32 hc_index, u32 thread_index)
   HTTP_DBG (1, "App disconnecting %x", hc_index);
 
   hc = http_conn_get_w_thread (hc_index, thread_index);
+  if (hc->state == HTTP_CONN_STATE_CONNECTING)
+    {
+      hc->state = HTTP_CONN_STATE_APP_CLOSED;
+      http_disconnect_transport (hc);
+      return;
+    }
+
   as = session_get_from_handle (hc->h_pa_session_handle);
 
   /* Nothing more to send, confirm close */
@@ -856,10 +1247,10 @@ http_app_tx_callback (void *session, transport_send_params_t *sp)
   http_conn_t *hc;
 
   hc = http_conn_get_w_thread (as->connection_index, as->thread_index);
-  if (hc->req_state < HTTP_REQ_STATE_WAIT_APP)
+  if (hc->http_state < HTTP_STATE_WAIT_APP)
     {
       if (hc->state != HTTP_CONN_STATE_CLOSED)
-	clib_warning ("app data req state %u session state %u", hc->req_state,
+	clib_warning ("app data req state %u session state %u", hc->http_state,
 		      hc->state);
       svm_fifo_dequeue_drop_all (as->tx_fifo);
       return 0;
diff --git a/src/plugins/http/http.h b/src/plugins/http/http.h
index d18b057de19..04272aee6d6 100644
--- a/src/plugins/http/http.h
+++ b/src/plugins/http/http.h
@@ -49,7 +49,7 @@ typedef struct http_conn_id_
 STATIC_ASSERT (sizeof (http_conn_id_t) <= TRANSPORT_CONN_ID_LEN,
 	       "ctx id must be less than TRANSPORT_CONN_ID_LEN");
 
-typedef enum http_state_
+typedef enum http_conn_state_
 {
   HTTP_CONN_STATE_LISTEN,
   HTTP_CONN_STATE_CONNECTING,
@@ -59,13 +59,13 @@ typedef enum http_state_
   HTTP_CONN_STATE_CLOSED
 } http_conn_state_t;
 
-typedef enum http_req_state_
+typedef enum http_state_
 {
-  HTTP_REQ_STATE_WAIT_METHOD,
-  HTTP_REQ_STATE_WAIT_APP,
-  HTTP_REQ_STATE_SEND_MORE_DATA,
-  HTTP_REQ_N_STATES,
-} http_req_state_t;
+  HTTP_STATE_WAIT_METHOD,
+  HTTP_STATE_WAIT_APP,
+  HTTP_STATE_IO_MORE_DATA,
+  HTTP_N_STATES,
+} http_state_t;
 
 typedef enum http_req_method_
 {
@@ -143,6 +143,7 @@ typedef struct http_tc_
 #define h_tc_session_handle c_http_conn_id.tc_session_handle
 #define h_pa_wrk_index	    c_http_conn_id.parent_app_wrk_index
 #define h_pa_session_handle c_http_conn_id.app_session_handle
+#define h_pa_app_api_ctx    c_http_conn_id.parent_app_api_ctx
 #define h_hc_index	    connection.c_index
 
   http_conn_state_t state;
@@ -151,11 +152,14 @@ typedef struct http_tc_
   /*
    * Current request
    */
-  http_req_state_t req_state;
+  http_state_t http_state;
   http_req_method_t method;
   u8 *rx_buf;
   u32 rx_buf_offset;
   http_buffer_t tx_buf;
+  u8 is_client;
+  u32 to_recv;
+  u32 bytes_dequeued;
 } http_conn_t;
 
 typedef struct http_worker_