#!/usr/bin/env python3

import unittest
import socket
import binascii

from framework import VppTestCase, VppTestRunner

from scapy.packet import Raw
from scapy.layers.l2 import Ether
from scapy.layers.inet6 import IPv6, UDP, TCP
from util import ppp
from template_classifier import TestClassifier


class TestClassifierIP6(TestClassifier):
    """ Classifier IP6 Test Case """

    @classmethod
    def setUpClass(cls):
        super(TestClassifierIP6, cls).setUpClass()
        cls.af = socket.AF_INET6

    @classmethod
    def tearDownClass(cls):
        super(TestClassifierIP6, cls).tearDownClass()

    def test_iacl_src_ip(self):
        """ Source IP6 iACL test

        Test scenario for basic IP ACL with source IP
            - Create IPv6 stream for pg0 -> pg1 interface.
            - Create iACL with source IP address.
            - Send and verify received packets on pg1 interface.
        """

        # Basic iACL testing with source IP
        pkts = self.create_stream(self.pg0, self.pg1, self.pg_if_packet_sizes)
        self.pg0.add_stream(pkts)

        key = 'ip6_src'
        self.create_classify_table(
            key,
            self.build_ip6_mask(src_ip='ffffffffffffffffffffffffffffffff'))
        self.create_classify_session(
            self.acl_tbl_idx.get(key),
            self.build_ip6_match(src_ip=self.pg0.remote_ip6))
        self.input_acl_set_interface(self.pg0, self.acl_tbl_idx.get(key))
        self.acl_active_table = key

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        pkts = self.pg1.get_capture(len(pkts))
        self.verify_capture(self.pg1, pkts)
        self.pg0.assert_nothing_captured(remark="packets forwarded")
        self.pg2.assert_nothing_captured(remark="packets forwarded")

    def test_iacl_dst_ip(self):
        """ Destination IP6 iACL test

        Test scenario for basic IP ACL with destination IP
            - Create IPv6 stream for pg0 -> pg1 interface.
            - Create iACL with destination IP address.
            - Send and verify received packets on pg1 interface.
        """

        # Basic iACL testing with destination IP
        pkts = self.create_stream(self.pg0, self.pg1, self.pg_if_packet_sizes)
        self.pg0.add_stream(pkts)

        key = '
/*
 * Copyright (c) 2022 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <http/http.h>
#include <vnet/session/session.h>
#include <http/http_timer.h>

static http_main_t http_main;

#define HTTP_FIFO_THRESH (16 << 10)

const char *http_status_code_str[] = {
#define _(c, s, str) str,
  foreach_http_status_code
#undef _
};

const char *http_content_type_str[] = {
#define _(s, str) str,
  foreach_http_content_type
#undef _
};

const http_buffer_type_t msg_to_buf_type[] = {
  [HTTP_MSG_DATA_INLINE] = HTTP_BUFFER_FIFO,
  [HTTP_MSG_DATA_PTR] = HTTP_BUFFER_PTR,
};

static inline http_worker_t *
http_worker_get (u32 thread_index)
{
  return &http_main.wrk[thread_index];
}

static inline u32
http_conn_alloc_w_thread (u32 thread_index)
{
  http_worker_t *wrk = http_worker_get (thread_index);
  http_conn_t *hc;

  pool_get_zero (wrk->conn_pool, hc);
  hc->c_thread_index = thread_index;
  hc->h_hc_index = hc - wrk->conn_pool;
  hc->h_pa_session_handle = SESSION_INVALID_HANDLE;
  hc->h_tc_session_handle = SESSION_INVALID_HANDLE;
  return hc->h_hc_index;
}

static inline http_conn_t *
http_conn_get_w_thread (u32 hc_index, u32 thread_index)
{
  http_worker_t *wrk = http_worker_get (thread_index);
  return pool_elt_at_index (wrk->conn_pool, hc_index);
}

void
http_conn_free (http_conn_t *hc)
{
  http_worker_t *wrk = http_worker_get (hc->c_thread_index);
  pool_put (wrk->conn_pool, hc);
}

static u32
http_listener_alloc (void)
{
  http_main_t *hm = &http_main;
  http_conn_t *ctx;

  pool_get_zero (hm->listener_ctx_pool, ctx);
  ctx->c_c_index = ctx - hm->listener_ctx_pool;
  return ctx->c_c_index;
}

http_conn_t *
http_listener_get (u32 ctx_index)
{
  return pool_elt_at_index (http_main.listener_ctx_pool, ctx_index);
}

void
http_disconnect_transport (http_conn_t *hc)
{
  vnet_disconnect_args_t a = {
    .handle = hc->h_tc_session_handle,
    .app_index = http_main.app_index,
  };

  hc->state = HTTP_CONN_STATE_CLOSED;

  if (vnet_disconnect_session (&a))
    clib_warning ("disconnect returned");
}

static void
http_conn_timeout_cb (void *hc_handlep)
{
  http_conn_t *hc;
  uword hs_handle;

  hs_handle = pointer_to_uword (hc_handlep);
  hc = http_conn_get_w_thread (hs_handle & 0x00FFFFFF, hs_handle >> 24);

  HTTP_DBG (1, "terminate thread %d index %d hs %llx", hs_handle >> 24,
	    hs_handle & 0x00FFFFFF, hc);
  if (!hc)
    return;

  hc->timer_handle = ~0;
  session_transport_closing_notify (&hc->connection);
  http_disconnect_transport (hc);
}

int
http_ts_accept_callback (session_t *ts)
{
  session_t *ts_listener, *as, *asl;
  app_worker_t *app_wrk;
  http_conn_t *lhc, *hc;
  u32 hc_index, thresh;
  int rv;

  ts_listener = listen_session_get_from_handle (ts->listener_handle);
  lhc = http_listener_get (ts_listener->opaque);

  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->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;

  ts->session_state = SESSION_STATE_READY;
  ts->opaque = hc_index;

  /*
   * 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;
  as->connection_index = hc->c_c_index;
  as->session_state = SESSION_STATE_ACCEPTING;

  asl = listen_session_get_from_handle (lhc->h_pa_session_handle);
  as->session_type = asl->session_type;
  as->listener_handle = lhc->h_pa_session_handle;

  /*
   * Init session fifos and notify app
   */
  if ((rv = app_worker_init_accepted (as)))
    {
      HTTP_DBG (1, "failed to allocate fifos");
      session_free (as);
      return rv;
    }

  hc->h_pa_session_handle = session_handle (as);
  hc->h_pa_wrk_index = as->app_wrk_index;
  app_wrk = app_worker_get (as->app_wrk_index);

  HTTP_DBG (1, "Accepted on listener %u new connection [%u]%x",
	    ts_listener->opaque, vlib_get_thread_index (), hc_index);

  if ((rv = app_worker_accept_notify (app_wrk, as)))
    {
      HTTP_DBG (0, "app accept returned");
      session_free (as);
      return rv;
    }

  /* Avoid enqueuing small chunks of data on transport tx notifications. If
   * the fifo is small (under 16K) we set the threshold to it's size, meaning
   * a notification will be given when the fifo empties.
   */
  thresh = clib_min (svm_fifo_size (ts->tx_fifo), HTTP_FIFO_THRESH);
  svm_fifo_set_deq_thresh (ts->tx_fifo, thresh);

  http_conn_timer_start (hc);

  return 0;
}

static int
http_ts_connected_callback (u32 http_app_index, u32 hc_index, session_t *ts,
			    session_error_t err)
{
  clib_warning ("not supported");
  return 0;
}

static void
http_ts_disconnect_callback (session_t *ts)
{
  http_conn_t *hc;

  hc = http_conn_get_w_thread (ts->opaque, ts->thread_index);

  if (hc->state < HTTP_CONN_STATE_TRANSPORT_CLOSED)
    hc->state = HTTP_CONN_STATE_TRANSPORT_CLOSED;

  if (!svm_fifo_max_dequeue_cons (ts->rx_fifo))
    session_transport_closing_notify (&hc->connection);
}

static void
http_ts_reset_callback (session_t *ts)
{
  http_conn_t *ctx;

  ctx = http_conn_get_w_thread (ts->opaque, ts->thread_index);

  if (ctx->state < HTTP_CONN_STATE_TRANSPORT_CLOSED)
    ctx->state = HTTP_CONN_STATE_TRANSPORT_CLOSED;

  if (!svm_fifo_max_dequeue_cons (ts->rx_fifo))
    session_transport_reset_notify (&ctx->connection);
}

/**
 * http error boilerplate
 */
static const char *http_error_template = "HTTP/1.1 %s\r\n"
					 "Date: %U GMT\r\n"
					 "Content-Type: text/html\r\n"
					 "Connection: close\r\n"
					 "Pragma: no-cache\r\n"
					 "Content-Length: 0\r\n\r\n";

/**
 * http response boilerplate
 */
static const char *http_response_template = "HTTP/1.1 200 OK\r\n"
					    "Date: %U GMT\r\n"
					    "Expires: %U GMT\r\n"
					    "Server: VPP Static\r\n"
					    "Content-Type: %s\r\n"
					    "Content-Length: %d\r\n\r\n";

static u32
send_data (http_conn_t *hc, u8 *data, u32 length, u32 offset)
{
  const u32 max_burst = 64 << 10;
  session_t *ts;
  u32 to_send;
  int sent;

  ts = session_get_from_handle (hc->h_tc_session_handle);

  to_send = clib_min (length - offset, max_burst);
  sent = svm_fifo_enqueue (ts->tx_fifo, to_send, data + offset);

  if (sent <= 0)
    return offset;

  if (svm_fifo_set_event (ts->tx_fifo))
    session_send_io_evt_to_thread (ts->tx_fifo, SESSION_IO_EVT_TX);

  return (offset + sent);
}

static void
send_error (http_conn_t *hc, http_status_code_t ec)
{
  http_main_t *hm = &http_main;
  u8 *data;
  f64 now;

  if (ec >= HTTP_N_STATUS)
    ec = HTTP_STATUS_INTERNAL_ERROR;

  now = clib_timebase_now (&hm->timebase);
  data = format (0, http_error_template, http_status_code_str[ec],
		 format_clib_timebase_time, now);
  send_data (hc, data, vec_len (data), 0);
  vec_free (data);
}

static int
read_request (http_conn_t *hc)
{
  u32 max_deq, cursize;
  session_t *ts;
  int n_read;

  ts = session_get_from_handle (hc->h_tc_session_handle);

  cursize = vec_len (hc->rx_buf);
  max_deq = svm_fifo_max_dequeue (ts->rx_fifo);
  if (PREDICT_FALSE (max_deq == 0))
    return -1;

  vec_validate (hc->rx_buf, cursize + max_deq - 1);
  n_read = svm_fifo_dequeue (ts->rx_fifo, max_deq, hc->rx_buf + cursize);
  ASSERT (n_read == max_deq);

  if (svm_fifo_is_empty (ts->rx_fifo))
    svm_fifo_unset_event (ts->rx_fifo);

  _vec_len (hc->rx_buf) = cursize + n_read;
  return 0;
}

static int
v_find_index (u8 *vec, u32 offset, char *str)
{
  int start_index = offset;
  u32 slen = (u32) strnlen_s_inline (str, 8);
  u32 vlen = vec_len (vec);

  ASSERT (slen > 0);

  if (vlen <= slen)
    return -1;

  for (; start_index < (vlen - slen); start_index++)
    {
      if (!memcmp (vec + start_index, str, slen))
	return start_index;
    }

  return -1;
}

/**
 * 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)
{
  http_status_code_t ec;
  app_worker_t *app_wrk;
  http_msg_t msg;
  session_t *as;
  int i, rv;
  u32 len;
  u8 *buf;

  rv = read_request (hc);

  /* Nothing yet, wait for data or timer expire */
  if (rv)
    return 0;

  if (vec_len (hc->rx_buf) < 8)
    {
      ec = HTTP_STATUS_BAD_REQUEST;
      goto error;
    }

  if ((i = v_find_index (hc->rx_buf, 0, "GET ")) >= 0)
    {
      hc->method = HTTP_REQ_GET;
      hc->rx_buf_offset = i + 5;

      i = v_find_index (hc->rx_buf, hc->rx_buf_offset, "HTTP");
      if (i < 0)
	{
	  ec = HTTP_STATUS_BAD_REQUEST;
	  goto error;
	}

      len = i - hc->rx_buf_offset - 1;
    }
  else if ((i = v_find_index (hc->rx_buf, 0, "POST ")) >= 0)
    {
      hc->method = HTTP_REQ_POST;
      hc->rx_buf_offset = i + 6;
      len = vec_len (hc->rx_buf) - hc->rx_buf_offset - 1;
    }
  else
    {
      HTTP_DBG (0, "Unknown http method");
      ec = HTTP_STATUS_METHOD_NOT_ALLOWED;
      goto error;
    }

  buf = &hc->rx_buf[hc->rx_buf_offset];

  msg.type = HTTP_MSG_REQUEST;
  msg.method_type = hc->method;
  msg.content_type = HTTP_CONTENT_TEXT_HTML;
  msg.data.type = HTTP_MSG_DATA_INLINE;
  msg.data.len = len;

  svm_fifo_seg_t segs[2] = { { (u8 *) &msg, sizeof (msg) }, { buf, len } };

  as = session_get_from_handle (hc->h_pa_session_handle);
  rv = svm_fifo_enqueue_segments (as->rx_fifo, segs, 2, 0 /* allow partial */);
  if (rv < 0 || rv != sizeof (msg) + len)
    {
      clib_warning ("failed app enqueue");
      /* 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;
    }

  vec_free (hc->rx_buf);
  hc->req_state = HTTP_REQ_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;

error:

  send_error (hc, ec);
  session_transport_closing_notify (&hc->connection);
  http_disconnect_transport (hc);

  return -1;
}

/**
 * waiting for data from app
 */
static int
state_wait_app (http_conn_t *hc, transport_send_params_t *sp)
{
  http_main_t *hm = &http_main;
  http_status_code_t ec;
  http_msg_t msg;
  session_t *as;
  u8 *header;
  u32 offset;
  f64 now;
  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_REPLY || msg.data.type > HTTP_MSG_DATA_PTR)
    {
      clib_warning ("unexpected msg type from app %u", msg.type);
      ec = HTTP_STATUS_INTERNAL_ERROR;
      goto error;
    }

  if (msg.code != HTTP_STATUS_OK)
    {
      ec = msg.code;
      goto error;
    }

  http_buffer_init (&hc->tx_buf, msg_to_buf_type[msg.data.type], as->tx_fifo,
		    msg.data.len);

  /*
   * Add headers. For now:
   * - current time
   * - expiration time
   * - content type
   * - data length
   */
  now = clib_timebase_now (&hm->timebase);
  header = format (0, http_response_template,
		   /* Date */
		   format_clib_timebase_time, now,
		   /* Expires */
		   format_clib_timebase_time, now + 600.0,
		   /* Content type */
		   http_content_type_str[msg.content_type],
		   /* Length */
		   msg.data.len);

  offset = send_data (hc, header, vec_len (header), 0);
  if (offset != vec_len (header))
    {
      clib_warning ("couldn't send response header!");
      ec = HTTP_STATUS_INTERNAL_ERROR;
      goto error;
    }
  vec_free (header);

  /* Start sending the actual data */
  hc->req_state = HTTP_REQ_STATE_SEND_MORE_DATA;

  ASSERT (sp->max_burst_size >= offset);
  sp->max_burst_size -= offset;

  return 1;

error:

  send_error (hc, ec);
  hc->req_state = HTTP_REQ_STATE_WAIT_METHOD;
  session_transport_closing_notify (&hc->connection);
  http_disconnect_transport (hc);

  /* stop state machine processing */
  return 0;
}

static int
state_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;
  svm_fifo_seg_t *seg;
  session_t *ts;
  int sent = 0;

  max_send = clib_min (max_send, sp->max_burst_size);
  ts = session_get_from_handle (hc->h_tc_session_handle);
  if ((seg = http_buffer_get_segs (hb, max_send, &n_segs)))
    sent = svm_fifo_enqueue_segments (ts->tx_fifo, seg, n_segs,
				      1 /* allow partial */);

  if (sent > 0)
    {
      /* Ask scheduler to notify app of deq event if needed */
      sp->bytes_dequeued += http_buffer_drain (hb, sent);
      sp->max_burst_size -= sent;
    }

  /* Not finished sending all data */
  if (!http_buffer_is_drained (hb))
    {
      if (sent && svm_fifo_set_event (ts->tx_fifo))
	session_send_io_evt_to_thread (ts->tx_fifo, SESSION_IO_EVT_TX);

      if (svm_fifo_max_enqueue (ts->tx_fifo) < HTTP_FIFO_THRESH)
	{
	  /* Deschedule http session and wait for deq notification if
	   * underlying ts tx fifo almost full */
	  svm_fifo_add_want_deq_ntf (ts->tx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
	  transport_connection_deschedule (&hc->connection);
	  sp->flags |= TRANSPORT_SND_F_DESCHED;
	}
    }
  else
    {
      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;
      http_buffer_free (&hc->tx_buf);
    }

  return 0;
}

typedef int (*http_sm_handler) (http_conn_t *, transport_send_params_t *sp);

static http_sm_handler req_state_funcs[HTTP_REQ_N_STATES] = {
  /* Waiting for GET, POST, etc. */
  state_wait_method,
  /* Wait for data from app */
  state_wait_app,
  /* Send more data */
  state_send_more_data,
};

static void
http_req_run_state_machine (http_conn_t *hc, transport_send_params_t *sp)
{
  int rv;

  do
    {
      rv = req_state_funcs[hc->req_state](hc, sp);
      if (rv < 0)
	return;
    }
  while (rv);

  /* Reset the session expiration timer */
  http_conn_timer_update (hc);
}

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->req_state != HTTP_REQ_STATE_WAIT_METHOD)
    {
      clib_warning ("tcp data in req state %u", hc->req_state);
      return 0;
    }

  http_req_run_state_machine (hc, 0);

  if (hc->state == HTTP_CONN_STATE_TRANSPORT_CLOSED)
    {
      if (!svm_fifo_max_dequeue_cons (ts->rx_fifo))
	session_transport_closing_notify (&hc->connection);
    }
  return 0;
}

int
http_ts_builtin_tx_callback (session_t *ts)
{
  http_conn_t *hc;

  hc = http_conn_get_w_thread (ts->opaque, ts->thread_index);
  transport_connection_reschedule (&hc->connection);

  return 0;
}

static void
http_ts_cleanup_callback (session_t *ts, session_cleanup_ntf_t ntf)
{
  http_conn_t *hc;

  if (ntf == SESSION_CLEANUP_TRANSPORT)
    return;

  hc = http_conn_get_w_thread (ts->opaque, ts->thread_index);
  if (!hc)
    {
      clib_warning ("no http connection for %u", ts->session_index);
      return;
    }

  vec_free (hc->rx_buf);

  http_buffer_free (&hc->tx_buf);
  http_conn_timer_stop (hc);

  session_transport_delete_notify (&hc->connection);
  http_conn_free (hc);
}

int
http_add_segment_callback (u32 client_index, u64 segment_handle)
{
  /* No-op for builtin */
  return 0;
}

int
http_del_segment_callback (u32 client_index, u64 segment_handle)
{
  return 0;
}

static session_cb_vft_t http_app_cb_vft = {
  .session_accept_callback = http_ts_accept_callback,
  .session_disconnect_callback = http_ts_disconnect_callback,
  .session_connected_callback = http_ts_connected_callback,
  .session_reset_callback = http_ts_reset_callback,
  .session_cleanup_callback = http_ts_cleanup_callback,
  .add_segment_callback = http_add_segment_callback,
  .del_segment_callback = http_del_segment_callback,
  .builtin_app_rx_callback = http_ts_rx_callback,
  .builtin_app_tx_callback = http_ts_builtin_tx_callback,
};

static clib_error_t *
http_transport_enable (vlib_main_t *vm, u8 is_en)
{
  u32 add_segment_size = 256 << 20, first_seg_size = 32 << 20;
  vnet_app_detach_args_t _da, *da = &_da;
  vnet_app_attach_args_t _a, *a = &_a;
  u64 options[APP_OPTIONS_N_OPTIONS];
  http_main_t *hm = &http_main;
  u32 fifo_size = 128 << 12;

  if (!is_en)
    {
      da->app_index = hm->app_index;
      da->api_client_index = APP_INVALID_INDEX;
      vnet_application_detach (da);
      return 0;
    }

  vec_validate (hm->wrk, vlib_num_workers ());

  first_seg_size = hm->first_seg_size ? hm->first_seg_size : first_seg_size;
  fifo_size = hm->fifo_size ? hm->fifo_size : fifo_size;

  clib_memset (a, 0, sizeof (*a));
  clib_memset (options, 0, sizeof (options));

  a->session_cb_vft = &http_app_cb_vft;
  a->api_client_index = APP_INVALID_INDEX;
  a->options = options;
  a->name = format (0, "http");
  a->options[APP_OPTIONS_SEGMENT_SIZE] = first_seg_size;
  a->options[APP_OPTIONS_ADD_SEGMENT_SIZE] = add_segment_size;
  a->options[APP_OPTIONS_RX_FIFO_SIZE] = fifo_size;
  a->options[APP_OPTIONS_TX_FIFO_SIZE] = fifo_size;
  a->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_IS_BUILTIN;
  a->options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_GLOBAL_SCOPE;
  a->options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_IS_TRANSPORT_APP;

  if (vnet_application_attach (a))
    return clib_error_return (0, "failed to attach http app");

  hm->app_index = a->app_index;
  vec_free (a->name);

  clib_timebase_init (&hm->timebase, 0 /* GMT */, CLIB_TIMEBASE_DAYLIGHT_NONE,
		      &vm->clib_time /* share the system clock */);

  http_timers_init (vm, http_conn_timeout_cb);

  return 0;
}

static int
http_transport_connect (transport_endpoint_cfg_t *tep)
{
  return -1;
}

static u32
http_start_listen (u32 app_listener_index, transport_endpoint_cfg_t *tep)
{
  vnet_listen_args_t _args = {}, *args = &_args;
  session_t *tc_listener, *app_listener;
  http_main_t *hm = &http_main;
  session_endpoint_cfg_t *sep;
  app_worker_t *app_wrk;
  transport_proto_t tp;
  app_listener_t *al;
  application_t *app;
  http_conn_t *lhc;
  u32 lhc_index;

  sep = (session_endpoint_cfg_t *) tep;

  app_wrk = app_worker_get (sep->app_wrk_index);
  app = application_get (app_wrk->app_index);

  args->app_index = hm->app_index;
  args->sep_ext = *sep;
  args->sep_ext.ns_index = app->ns_index;
  tp = sep->ext_cfg ? TRANSPORT_PROTO_TLS : TRANSPORT_PROTO_TCP;
  args->sep_ext.transport_proto = tp;

  if (vnet_listen (args))
    return SESSION_INVALID_INDEX;

  lhc_index = http_listener_alloc ();
  lhc = http_listener_get (lhc_index);

  /* Grab transport connection listener and link to http listener */
  lhc->h_tc_session_handle = args->handle;
  al = app_listener_get_w_handle (lhc->h_tc_session_handle);
  tc_listener = app_listener_get_session (al);
  tc_listener->opaque = lhc_index;

  /* Grab application listener and link to http listener */
  app_listener = listen_session_get (app_listener_index);
  lhc->h_pa_wrk_index = sep->app_wrk_index;
  lhc->h_pa_session_handle = listen_session_get_handle (app_listener);
  lhc->c_flags |= TRANSPORT_CONNECTION_F_NO_LOOKUP;

  return lhc_index;
}

static void
http_transport_close (u32 hc_index, u32 thread_index)
{
  session_t *as;
  http_conn_t *hc;

  HTTP_DBG (1, "App disconnecting %x", hc_index);

  hc = http_conn_get_w_thread (hc_index, thread_index);
  as = session_get_from_handle (hc->h_pa_session_handle);

  /* Nothing more to send, confirm close */
  if (!svm_fifo_max_dequeue_cons (as->tx_fifo))
    {
      session_transport_closed_notify (&hc->connection);
      http_disconnect_transport (hc);
    }
  else
    {
      /* Wait for all data to be written to ts */
      hc->state = HTTP_CONN_STATE_APP_CLOSED;
    }
}

static transport_connection_t *
http_transport_get_connection (u32 hc_index, u32 thread_index)
{
  http_conn_t *hc = http_conn_get_w_thread (hc_index, thread_index);
  return &hc->connection;
}

static transport_connection_t *
http_transport_get_listener (u32 listener_index)
{
  http_conn_t *lhc = http_listener_get (listener_index);
  return &lhc->connection;
}

static int
http_app_tx_callback (void *session, transport_send_params_t *sp)
{
  session_t *as = (session_t *) session;
  u32 max_burst_sz, sent;
  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)
    {
      clib_warning ("app data in req state %u", hc->req_state);
      return 0;
    }

  max_burst_sz = sp->max_burst_size * TRANSPORT_PACER_MIN_MSS;
  sp->max_burst_size = max_burst_sz;

  http_req_run_state_machine (hc, sp);

  if (hc->state == HTTP_CONN_STATE_CLOSED)
    {
      if (!svm_fifo_max_dequeue_cons (as->rx_fifo))
	http_disconnect_transport (hc);
    }

  sent = max_burst_sz - sp->max_burst_size;

  return sent > 0 ? clib_max (sent / TRANSPORT_PACER_MIN_MSS, 1) : 0;
}

static void
http_transport_get_endpoint (u32 hc_index, u32 thread_index,
			     transport_endpoint_t *tep, u8 is_lcl)
{
  http_conn_t *hc = http_conn_get_w_thread (hc_index, thread_index);
  session_t *ts;

  ts = session_get_from_handle (hc->h_tc_session_handle);
  session_get_endpoint (ts, tep, is_lcl);
}

static u8 *
format_http_connection (u8 *s, va_list *args)
{
  http_conn_t *hc = va_arg (*args, http_conn_t *);
  session_t *ts;

  ts = session_get_from_handle (hc->h_tc_session_handle);
  s = format (s, "[%d:%d][H] app_wrk %u ts %d:%d", hc->c_thread_index,
	      hc->c_s_index, hc->h_pa_wrk_index, ts->thread_index,
	      ts->session_index);

  return s;
}

static u8 *
format_http_listener (u8 *s, va_list *args)
{
  http_conn_t *lhc = va_arg (*args, http_conn_t *);
  app_listener_t *al;
  session_t *lts;

  al = app_listener_get_w_handle (lhc->h_tc_session_handle);
  lts = app_listener_get_session (al);
  s = format (s, "[%d:%d][H] app_wrk %u ts %d:%d", lhc->c_thread_index,
	      lhc->c_s_index, lhc->h_pa_wrk_index, lts->thread_index,
	      lts->session_index);

  return s;
}

static u8 *
format_http_conn_state (u8 *s, va_list *args)
{
  http_conn_t *hc = va_arg (*args, http_conn_t *);

  switch (hc->state)
    {
    case HTTP_CONN_STATE_LISTEN:
      s = format (s, "LISTEN");
      break;
    case HTTP_CONN_STATE_CONNECTING:
      s = format (s, "CONNECTING");
      break;
    case HTTP_CONN_STATE_ESTABLISHED:
      s = format (s, "ESTABLISHED");
      break;
    case HTTP_CONN_STATE_TRANSPORT_CLOSED:
      s = format (s, "TRANSPORT_CLOSED");
      break;
    case HTTP_CONN_STATE_APP_CLOSED:
      s = format (s, "APP_CLOSED");
      break;
    case HTTP_CONN_STATE_CLOSED:
      s = format (s, "CLOSED");
      break;
    }

  return s;
}

static u8 *
format_http_transport_connection (u8 *s, va_list *args)
{
  u32 tc_index = va_arg (*args, u32);
  u32 thread_index = va_arg (*args, u32);
  u32 verbose = va_arg (*args, u32);
  http_conn_t *hc;

  hc = http_conn_get_w_thread (tc_index, thread_index);

  s = format (s, "%-" SESSION_CLI_ID_LEN "U", format_http_connection, hc);
  if (verbose)
    {
      s =
	format (s, "%-" SESSION_CLI_STATE_LEN "U", format_http_conn_state, hc);
      if (verbose > 1)
	s = format (s, "\n");
    }

  return s;
}

static u8 *
format_http_transport_listener (u8 *s, va_list *args)
{
  u32 tc_index = va_arg (*args, u32);
  u32 __clib_unused thread_index = va_arg (*args, u32);
  u32 __clib_unused verbose = va_arg (*args, u32);
  http_conn_t *lhc = http_listener_get (tc_index);

  s = format (s, "%-" SESSION_CLI_ID_LEN "U", format_http_listener, lhc);
  if (verbose)
    s =
      format (s, "%-" SESSION_CLI_STATE_LEN "U", format_http_conn_state, lhc);
  return s;
}

static const transport_proto_vft_t http_proto = {
  .enable = http_transport_enable,
  .connect = http_transport_connect,
  .start_listen = http_start_listen,
  .close = http_transport_close,
  .custom_tx = http_app_tx_callback,
  .get_connection = http_transport_get_connection,
  .get_listener = http_transport_get_listener,
  .get_transport_endpoint = http_transport_get_endpoint,
  .format_connection = format_http_transport_connection,
  .format_listener = format_http_transport_listener,
  .transport_options = {
    .name = "http",
    .short_name = "H",
    .tx_type = TRANSPORT_TX_INTERNAL,
    .service_type = TRANSPORT_SERVICE_APP,
  },
};

static clib_error_t *
http_transport_init (vlib_main_t *vm)
{
  transport_register_protocol (TRANSPORT_PROTO_HTTP, &http_proto,
			       FIB_PROTOCOL_IP4, ~0);
  transport_register_protocol (TRANSPORT_PROTO_HTTP, &http_proto,
			       FIB_PROTOCOL_IP6, ~0);
  return 0;
}

VLIB_INIT_FUNCTION (http_transport_init);

VLIB_PLUGIN_REGISTER () = {
  .version = VPP_BUILD_VER,
  .description = "Hypertext Transfer Protocol (HTTP)",
  .default_disabled = 0,
};

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */