http: add http protocol plugin

Basic HTTP/1.1 server side implementation.

Type: feature

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: I06bddaf7f11e28db802b4cd7ef8160c78cb019b6

5 files changed, 1396 insertions, 0 deletions

diff --git a/src/plugins/http/CMakeLists.txt b/src/plugins/http/CMakeLists.txt
new file mode 100644
index 00000000000..9f5ce778739
--- /dev/null
+++ b/src/plugins/http/CMakeLists.txt
@@ -0,0 +1,18 @@
+# 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.
+
+add_vpp_plugin(http
+  SOURCES
+  http.c
+  http_timer.c
+)
diff --git a/src/plugins/http/http.c b/src/plugins/http/http.c
new file mode 100644
index 00000000000..5cdbaa7df3e
--- /dev/null
+++ b/src/plugins/http/http.c
@@ -0,0 +1,1002 @@
+/*
+ * 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;
+
+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 _
+};
+
+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_buffer_init (http_buffer_t *hb, svm_fifo_t *f, u32 data_len)
+{
+  hb->len = data_len;
+  hb->offset = 0;
+  hb->cur_seg = 0;
+  hb->src = f;
+  hb->segs = 0;
+}
+
+static void
+http_buffer_free (http_buffer_t *hb)
+{
+  hb->src = 0;
+  vec_free (hb->segs);
+}
+
+svm_fifo_seg_t *
+http_buffer_get_segs (http_buffer_t *hb, u32 max_len, u32 *n_segs)
+{
+  u32 _n_segs = 5;
+  int len;
+
+  max_len = clib_max (hb->len - hb->offset, max_len);
+
+  vec_validate (hb->segs, _n_segs);
+
+  len = svm_fifo_segments (hb->src, 0, hb->segs, &_n_segs, max_len);
+  if (len < 0)
+    return 0;
+
+  *n_segs = _n_segs;
+
+  HTTP_DBG (1, "available to send %u n_segs %u", len, *n_segs);
+
+  return hb->segs;
+}
+
+void
+http_buffer_drain (http_buffer_t *hb, u32 len)
+{
+  hb->offset += len;
+  svm_fifo_dequeue_drop (hb->src, len);
+  HTTP_DBG (1, "drained %u len %u offset %u", len, hb->len, hb->offset);
+}
+
+static inline u8
+http_buffer_is_drained (http_buffer_t *hb)
+{
+  ASSERT (hb->offset <= hb->len);
+  return (hb->offset == hb->len);
+}
+
+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;
+  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;
+    }
+
+  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, char *str)
+{
+  int start_index;
+  u32 slen = (u32) strnlen_s_inline (str, 8);
+  u32 vlen = vec_len (vec);
+
+  ASSERT (slen > 0);
+
+  if (vlen <= slen)
+    return -1;
+
+  for (start_index = 0; start_index < (vlen - slen); start_index++)
+    {
+      if (!memcmp (vec, 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_main_t *hm = &http_main;
+  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)
+    {
+      send_error (hc, HTTP_STATUS_BAD_REQUEST);
+      http_disconnect_transport (hc);
+      return -1;
+    }
+
+  if ((i = v_find_index (hc->rx_buf, "GET ")) >= 0)
+    {
+      hc->method = HTTP_REQ_GET;
+      hc->rx_buf_offset = i + 5;
+    }
+  else if ((i = v_find_index (hc->rx_buf, "POST ")) >= 0)
+    {
+      hc->method = HTTP_REQ_POST;
+      hc->rx_buf_offset = i + 6;
+    }
+  else
+    {
+      if (hm->debug_level > 1)
+	clib_warning ("Unknown http method");
+
+      send_error (hc, HTTP_STATUS_METHOD_NOT_ALLOWED);
+      http_disconnect_transport (hc);
+      return -1;
+    }
+
+  buf = &hc->rx_buf[hc->rx_buf_offset];
+  len = vec_len (hc->rx_buf) - hc->rx_buf_offset;
+
+  msg.type = HTTP_MSG_REQUEST;
+  msg.data.content_type = HTTP_CONTENT_TEXT_HTML;
+  msg.data.len = len;
+  msg.data.offset = 0;
+
+  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;
+}
+
+/**
+ * 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)
+    {
+      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, 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.data.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;
+
+  return 1;
+
+error:
+
+  send_error (hc, ec);
+  hc->req_state = HTTP_REQ_STATE_WAIT_METHOD;
+  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;
+
+  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)
+    {
+      http_buffer_drain (hb, sent);
+
+      /* Ask scheduler to notify app of deq event if needed */
+      sp->max_burst_size = sent;
+    }
+  else
+    {
+      sp->max_burst_size = 0;
+    }
+
+  /* Not finished sending all data */
+  if (!http_buffer_is_drained (hb))
+    {
+      if (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) < 16 << 10)
+	{
+	  /* 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 (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)
+{
+  clib_warning ("called");
+  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_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;
+  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;
+    }
+
+  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);
+    }
+  return 0;
+}
+
+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,
+  .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:
+ */
diff --git a/src/plugins/http/http.h b/src/plugins/http/http.h
new file mode 100644
index 00000000000..209fc3236df
--- /dev/null
+++ b/src/plugins/http/http.h
@@ -0,0 +1,194 @@
+/*
+ * 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.
+ */
+
+#ifndef SRC_PLUGINS_HTTP_HTTP_H_
+#define SRC_PLUGINS_HTTP_HTTP_H_
+
+#include <vnet/plugin/plugin.h>
+#include <vpp/app/version.h>
+
+#include <vppinfra/time_range.h>
+
+#include <vnet/session/application_interface.h>
+#include <vnet/session/application.h>
+
+#define HTTP_DEBUG 0
+
+#if HTTP_DEBUG
+#define HTTP_DBG(_lvl, _fmt, _args...)                                        \
+  if (_lvl <= HTTP_DEBUG)                                                     \
+  clib_warning (_fmt, ##_args)
+#else
+#define HTTP_DBG(_lvl, _fmt, _args...)
+#endif
+
+typedef struct http_conn_id_
+{
+  union
+  {
+    session_handle_t app_session_handle;
+    u32 parent_app_api_ctx;
+  };
+  session_handle_t tc_session_handle;
+  u32 parent_app_wrk_index;
+} http_conn_id_t;
+
+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_
+{
+  HTTP_CONN_STATE_LISTEN,
+  HTTP_CONN_STATE_CONNECTING,
+  HTTP_CONN_STATE_ESTABLISHED,
+  HTTP_CONN_STATE_TRANSPORT_CLOSED,
+  HTTP_CONN_STATE_APP_CLOSED,
+  HTTP_CONN_STATE_CLOSED
+} http_conn_state_t;
+
+typedef enum http_req_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;
+
+typedef enum http_req_method_
+{
+  HTTP_REQ_GET = 0,
+  HTTP_REQ_POST,
+} http_req_method_t;
+
+typedef enum http_msg_type_
+{
+  HTTP_MSG_REQUEST,
+  HTTP_MSG_REPLY
+} http_msg_type_t;
+
+#define foreach_http_content_type                                             \
+  _ (TEXT_HTML, "text/html")                                                  \
+  _ (TEXT_CSS, "text/css")                                                    \
+  _ (TEXT_JS, "text/javascript")                                              \
+  _ (TEXT_JSON, "application/json")
+
+typedef enum http_content_type_
+{
+#define _(s, str) HTTP_CONTENT_##s,
+  foreach_http_content_type
+#undef _
+} http_content_type_t;
+
+#define foreach_http_status_code                                              \
+  _ (200, OK, "200 OK")                                                       \
+  _ (400, BAD_REQUEST, "400 Bad Request")                                     \
+  _ (405, METHOD_NOT_ALLOWED, "405 Method Not Allowed")                       \
+  _ (500, INTERNAL_ERROR, "500 Internal Server Error")
+
+typedef enum http_status_code_
+{
+#define _(c, s, str) HTTP_STATUS_##s,
+  foreach_http_status_code
+#undef _
+    HTTP_N_STATUS
+} http_status_code_t;
+
+typedef struct http_msg_data_
+{
+  http_content_type_t content_type;
+  u32 len;
+  u32 offset;
+  u8 data[0];
+} http_msg_data_t;
+
+typedef struct http_msg_
+{
+  http_msg_type_t type;
+  union
+  {
+    http_req_method_t method_type;
+    http_status_code_t code;
+  };
+  http_msg_data_t data;
+} http_msg_t;
+
+typedef struct http_buffer_
+{
+  svm_fifo_t *src;
+  svm_fifo_seg_t *segs;
+  u32 len;
+  u32 cur_seg;
+  u32 offset;
+} http_buffer_t;
+
+typedef struct http_tc_
+{
+  union
+  {
+    transport_connection_t connection;
+    http_conn_id_t c_http_conn_id;
+  };
+#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_hc_index	    connection.c_index
+
+  http_conn_state_t state;
+  u32 timer_handle;
+
+  /*
+   * Current request
+   */
+  http_req_state_t req_state;
+  http_req_method_t method;
+  u8 *rx_buf;
+  u32 rx_buf_offset;
+  http_buffer_t tx_buf;
+} http_conn_t;
+
+typedef struct http_worker_
+{
+  http_conn_t *conn_pool;
+} http_worker_t;
+
+typedef struct http_main_
+{
+  http_worker_t *wrk;
+  http_conn_t *listener_ctx_pool;
+  u32 app_index;
+
+  clib_timebase_t timebase;
+
+  /*
+   * Runtime config
+   */
+  u8 debug_level;
+
+  /*
+   * Config
+   */
+  u64 first_seg_size;
+  u32 fifo_size;
+} http_main_t;
+
+#endif /* SRC_PLUGINS_HTTP_HTTP_H_ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/http/http_timer.c b/src/plugins/http/http_timer.c
new file mode 100644
index 00000000000..42fe69076fe
--- /dev/null
+++ b/src/plugins/http/http_timer.c
@@ -0,0 +1,91 @@
+/*
+ * 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_timer.h>
+#include <vnet/session/session.h>
+
+http_tw_ctx_t http_tw_ctx;
+
+static void
+http_timer_process_expired_cb (u32 *expired_timers)
+{
+  http_tw_ctx_t *twc = &http_tw_ctx;
+  u32 hs_handle;
+  int i;
+
+  for (i = 0; i < vec_len (expired_timers); i++)
+    {
+      /* Get session handle. The first bit is the timer id */
+      hs_handle = expired_timers[i] & 0x7FFFFFFF;
+      session_send_rpc_evt_to_thread (hs_handle >> 24, twc->cb_fn,
+				      uword_to_pointer (hs_handle, void *));
+    }
+}
+
+static uword
+http_timer_process (vlib_main_t *vm, vlib_node_runtime_t *rt, vlib_frame_t *f)
+{
+  http_tw_ctx_t *twc = &http_tw_ctx;
+  f64 now, timeout = 1.0;
+  uword *event_data = 0;
+  uword __clib_unused event_type;
+
+  while (1)
+    {
+      vlib_process_wait_for_event_or_clock (vm, timeout);
+      now = vlib_time_now (vm);
+      event_type = vlib_process_get_events (vm, (uword **) &event_data);
+
+      /* expire timers */
+      clib_spinlock_lock (&twc->tw_lock);
+      tw_timer_expire_timers_2t_1w_2048sl (&twc->tw, now);
+      clib_spinlock_unlock (&twc->tw_lock);
+
+      vec_reset_length (event_data);
+    }
+  return 0;
+}
+
+VLIB_REGISTER_NODE (http_timer_process_node) = {
+  .function = http_timer_process,
+  .type = VLIB_NODE_TYPE_PROCESS,
+  .name = "http-timer-process",
+  .state = VLIB_NODE_STATE_DISABLED,
+};
+
+void
+http_timers_init (vlib_main_t *vm, http_conn_timeout_fn *cb_fn)
+{
+  http_tw_ctx_t *twc = &http_tw_ctx;
+  vlib_node_t *n;
+
+  tw_timer_wheel_init_2t_1w_2048sl (&twc->tw, http_timer_process_expired_cb,
+				    1.0 /* timer interval */, ~0);
+  clib_spinlock_init (&twc->tw_lock);
+  twc->cb_fn = cb_fn;
+
+  vlib_node_set_state (vm, http_timer_process_node.index,
+		       VLIB_NODE_STATE_POLLING);
+  n = vlib_get_node (vm, http_timer_process_node.index);
+  vlib_start_process (vm, n->runtime_index);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/http/http_timer.h b/src/plugins/http/http_timer.h
new file mode 100644
index 00000000000..eec5a4595fe
--- /dev/null
+++ b/src/plugins/http/http_timer.h
@@ -0,0 +1,91 @@
+/*
+ * 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.
+ */
+
+#ifndef SRC_PLUGINS_HTTP_HTTP_TIMER_H_
+#define SRC_PLUGINS_HTTP_HTTP_TIMER_H_
+
+#include <http/http.h>
+#include <vppinfra/tw_timer_2t_1w_2048sl.h>
+
+#define HTTP_CONN_TIMEOUT 60
+
+typedef void (http_conn_timeout_fn) (void *);
+
+typedef struct http_tw_ctx_
+{
+  tw_timer_wheel_2t_1w_2048sl_t tw;
+  clib_spinlock_t tw_lock;
+  http_conn_timeout_fn *cb_fn;
+} http_tw_ctx_t;
+
+extern http_tw_ctx_t http_tw_ctx;
+
+void http_timers_init (vlib_main_t *vm, http_conn_timeout_fn *cb_fn);
+
+static inline void
+http_conn_timer_start (http_conn_t *hc)
+{
+  http_tw_ctx_t *twc = &http_tw_ctx;
+  u32 hs_handle;
+  u64 timeout;
+
+  timeout = HTTP_CONN_TIMEOUT;
+  hs_handle = hc->c_thread_index << 24 | hc->c_c_index;
+
+  clib_spinlock_lock (&twc->tw_lock);
+  hc->timer_handle =
+    tw_timer_start_2t_1w_2048sl (&twc->tw, hs_handle, 0, timeout);
+  clib_spinlock_unlock (&twc->tw_lock);
+}
+
+static inline void
+http_conn_timer_stop (http_conn_t *hc)
+{
+  http_tw_ctx_t *twc = &http_tw_ctx;
+
+  if (hc->timer_handle == ~0)
+    return;
+
+  clib_spinlock_lock (&twc->tw_lock);
+  tw_timer_stop_2t_1w_2048sl (&twc->tw, hc->timer_handle);
+  hc->timer_handle = ~0;
+  clib_spinlock_unlock (&twc->tw_lock);
+}
+
+static inline void
+http_conn_timer_update (http_conn_t *hc)
+{
+  http_tw_ctx_t *twc = &http_tw_ctx;
+  u64 timeout;
+
+  if (hc->timer_handle == ~0)
+    return;
+
+  timeout = HTTP_CONN_TIMEOUT;
+
+  clib_spinlock_lock (&twc->tw_lock);
+  tw_timer_update_2t_1w_2048sl (&twc->tw, hc->timer_handle, timeout);
+  clib_spinlock_unlock (&twc->tw_lock);
+}
+
+#endif /* SRC_PLUGINS_HTTP_HTTP_TIMER_H_ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */