Builtin debug cli http server

Visit http://<vpp-ip>/show/interface or similar.

Change-Id: I076b4661cf19d1b94bb01efdadb5849446be915e
Signed-off-by: Dave Barach <dave@barachs.net>
diff --git a/src/vnet/tcp/builtin_http_server.c b/src/vnet/tcp/builtin_http_server.c
new file mode 100644
index 0000000..4e61fbd
--- /dev/null
+++ b/src/vnet/tcp/builtin_http_server.c
@@ -0,0 +1,634 @@
+/*
+* Copyright (c) 2015-2017 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 <vnet/vnet.h>
+#include <vlibmemory/api.h>
+#include <vnet/session/application.h>
+#include <vnet/session/application_interface.h>
+
+/* define message IDs */
+#include <vpp/api/vpe_msg_enum.h>
+
+/* define message structures */
+#define vl_typedefs
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_typedefs
+
+/* define generated endian-swappers */
+#define vl_endianfun
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
+#define vl_printfun
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_printfun
+
+typedef enum
+{
+  EVENT_WAKEUP = 1,
+} http_process_event_t;
+
+typedef struct
+{
+  u8 *rx_buf;
+  unix_shared_memory_queue_t **vpp_queue;
+  u64 byte_index;
+
+  uword *handler_by_get_request;
+
+  u32 *free_http_cli_process_node_indices;
+
+  /* Sever's event queue */
+  unix_shared_memory_queue_t *vl_input_queue;
+
+  /* API client handle */
+  u32 my_client_index;
+
+  u32 app_index;
+
+  /* process node index for evnt scheduling */
+  u32 node_index;
+  vlib_main_t *vlib_main;
+} http_server_main_t;
+
+http_server_main_t http_server_main;
+
+static void
+free_http_process (stream_session_t * s)
+{
+  vlib_node_runtime_t *rt;
+  vlib_main_t *vm = &vlib_global_main;
+  http_server_main_t *hsm = &http_server_main;
+  vlib_node_t *n;
+  u32 node_index;
+  stream_session_t **save_s;
+
+  node_index = (u64) (s->opaque[0]);
+  ASSERT (node_index != 0);
+
+  n = vlib_get_node (vm, node_index);
+  rt = vlib_node_get_runtime (vm, n->runtime_index);
+  save_s = (stream_session_t **) vlib_node_get_runtime (vm, n->runtime_index);
+
+  /* Reset session saved node index */
+  s->opaque[0] = 0;
+  /* Reset process session pointer */
+  *save_s = 0;
+
+  /* Turn off the process node */
+  vlib_node_set_state (vm, rt->node_index, VLIB_NODE_STATE_DISABLED);
+
+  /* add node index to the freelist */
+  vec_add1 (hsm->free_http_cli_process_node_indices, node_index);
+}
+
+static const char
+  *http_response = "HTTP/1.1 200 OK\r\n"
+  "Content-Type: text/html\r\n"
+  "Expires: Mon, 11 Jan 1970 10:10:10 GMT\r\n"
+  "Connection: close\r\n"
+  "Pragma: no-cache\r\n" "Content-Length: %d\r\n\r\n%s";
+
+static const char
+  *http_error_template = "HTTP/1.1 %s\r\n"
+  "Content-Type: text/html\r\n"
+  "Expires: Mon, 11 Jan 1970 10:10:10 GMT\r\n"
+  "Connection: close\r\n" "Pragma: no-cache\r\n" "Content-Length: 0\r\n\r\n";
+
+/* Header, including incantation to suppress favicon.ico requests */
+static const char
+  *html_header_template = "<html><head><title>%v</title>"
+  "</head><link rel=\"icon\" href=\"data:,\"><body><pre>";
+
+static const char *html_footer = "</pre></body></html>\r\n";
+
+static void
+http_cli_output (uword arg, u8 * buffer, uword buffer_bytes)
+{
+  u8 **output_vecp = (u8 **) arg;
+  u8 *output_vec;
+  u32 offset;
+
+  output_vec = *output_vecp;
+
+  offset = vec_len (output_vec);
+  vec_validate (output_vec, offset + buffer_bytes - 1);
+  clib_memcpy (output_vec + offset, buffer, buffer_bytes);
+
+  *output_vecp = output_vec;
+}
+
+void
+send_data (stream_session_t * s, u8 * data)
+{
+  session_fifo_event_t evt;
+  u32 offset, bytes_to_send;
+  f64 delay = 10e-3;
+  http_server_main_t *hsm = &http_server_main;
+  vlib_main_t *vm = hsm->vlib_main;
+  f64 last_sent_timer = vlib_time_now (vm);
+
+  bytes_to_send = vec_len (data);
+  offset = 0;
+
+  while (bytes_to_send > 0)
+    {
+      int actual_transfer;
+
+      actual_transfer = svm_fifo_enqueue_nowait
+	(s->server_tx_fifo, bytes_to_send, data + offset);
+
+      /* Made any progress? */
+      if (actual_transfer <= 0)
+	{
+	  vlib_process_suspend (vm, delay);
+	  /* 10s deadman timer */
+	  if (vlib_time_now (vm) > last_sent_timer + 10.0)
+	    {
+	      /* $$$$ FC: reset transport session here? */
+	      break;
+	    }
+	  /* Exponential backoff, within reason */
+	  if (delay < 1.0)
+	    delay = delay * 2.0;
+	}
+      else
+	{
+	  last_sent_timer = vlib_time_now (vm);
+	  offset += actual_transfer;
+	  bytes_to_send -= actual_transfer;
+
+	  if (svm_fifo_set_event (s->server_tx_fifo))
+	    {
+	      /* Fabricate TX event, send to vpp */
+	      evt.fifo = s->server_tx_fifo;
+	      evt.event_type = FIFO_EVENT_APP_TX;
+	      evt.event_id = 0;
+
+	      unix_shared_memory_queue_add (hsm->vpp_queue[s->thread_index],
+					    (u8 *) & evt,
+					    0 /* do wait for mutex */ );
+	    }
+	  delay = 10e-3;
+	}
+    }
+}
+
+static void
+send_error (stream_session_t * s, char *str)
+{
+  u8 *data;
+
+  data = format (0, http_error_template, str);
+  send_data (s, data);
+  vec_free (data);
+}
+
+static uword
+http_cli_process (vlib_main_t * vm,
+		  vlib_node_runtime_t * rt, vlib_frame_t * f)
+{
+  http_server_main_t *hsm = &http_server_main;
+  u8 *request = 0, *reply = 0;
+  stream_session_t **save_s;
+  stream_session_t *s;
+  unformat_input_t input;
+  int i;
+  u8 *http = 0, *html = 0;
+
+  save_s = vlib_node_get_runtime_data (hsm->vlib_main, rt->node_index);
+  s = *save_s;
+
+  request = (u8 *) (void *) (s->opaque[1]);
+  s->opaque[1] = 0;
+
+  if (vec_len (request) < 7)
+    {
+      send_error (s, "400 Bad Request");
+      goto out;
+    }
+
+  for (i = 0; i < vec_len (request) - 4; i++)
+    {
+      if (request[i] == 'G' &&
+	  request[i + 1] == 'E' &&
+	  request[i + 2] == 'T' && request[i + 3] == ' ')
+	goto found;
+    }
+bad_request:
+  send_error (s, "400 Bad Request");
+  goto out;
+
+found:
+  /* Lose "GET " */
+  vec_delete (request, i + 5, 0);
+
+  /* Replace slashes with spaces, stop at the end of the path */
+  i = 0;
+  while (1)
+    {
+      if (request[i] == '/')
+	request[i] = ' ';
+      else if (request[i] == ' ')
+	{
+	  /* vlib_cli_input is vector-based, no need for a NULL */
+	  _vec_len (request) = i;
+	  break;
+	}
+      i++;
+      /* Should never happen */
+      if (i == vec_len (request))
+	goto bad_request;
+    }
+
+  /* Generate the html header */
+  html = format (0, html_header_template, request /* title */ );
+
+  /* Run the command */
+  unformat_init_vector (&input, request);
+  vlib_cli_input (vm, &input, http_cli_output, (uword) & reply);
+  unformat_free (&input);
+  request = 0;
+
+  /* Generate the html page */
+  html = format (html, "%v", reply);
+  html = format (html, html_footer);
+  /* And the http reply */
+  http = format (0, http_response, vec_len (html), html);
+
+  /* Send it */
+  send_data (s, http);
+
+out:
+  /* Cleanup */
+  vec_free (request);
+  vec_free (reply);
+  vec_free (html);
+  vec_free (http);
+
+  free_http_process (s);
+  return (0);
+}
+
+static void
+alloc_http_process (stream_session_t * s)
+{
+  char *name;
+  vlib_node_t *n;
+  http_server_main_t *hsm = &http_server_main;
+  vlib_main_t *vm = hsm->vlib_main;
+  uword l = vec_len (hsm->free_http_cli_process_node_indices);
+  stream_session_t **save_s;
+
+  if (vec_len (hsm->free_http_cli_process_node_indices) > 0)
+    {
+      n = vlib_get_node (vm, hsm->free_http_cli_process_node_indices[l - 1]);
+
+      vlib_node_set_state (vm, n->index, VLIB_NODE_STATE_POLLING);
+
+      _vec_len (hsm->free_http_cli_process_node_indices) = l - 1;
+    }
+  else
+    {
+      static vlib_node_registration_t r = {
+	.function = http_cli_process,
+	.type = VLIB_NODE_TYPE_PROCESS,
+	.process_log2_n_stack_bytes = 16,
+	.runtime_data_bytes = sizeof (void *),
+      };
+
+      name = (char *) format (0, "http-cli-%d", l);
+
+      r.name = name;
+      vlib_register_node (vm, &r);
+      vec_free (name);
+
+      n = vlib_get_node (vm, r.index);
+    }
+
+  /* Save the node index in the stream_session_t. It won't be zero. */
+  s->opaque[0] = (u64) n->index;
+
+  /* Save the stream_session_t (pointer) in the node runtime */
+  save_s = vlib_node_get_runtime_data (vm, n->index);
+  *save_s = s;
+
+  vlib_start_process (vm, n->runtime_index);
+}
+
+static int
+builtin_session_accept_callback (stream_session_t * s)
+{
+  http_server_main_t *bsm = &http_server_main;
+
+  bsm->vpp_queue[s->thread_index] =
+    session_manager_get_vpp_event_queue (s->thread_index);
+  s->session_state = SESSION_STATE_READY;
+  bsm->byte_index = 0;
+  return 0;
+}
+
+static void
+builtin_session_disconnect_callback (stream_session_t * s)
+{
+  http_server_main_t *bsm = &http_server_main;
+  vnet_disconnect_args_t _a, *a = &_a;
+
+  a->handle = stream_session_handle (s);
+  a->app_index = bsm->app_index;
+  vnet_disconnect_session (a);
+}
+
+static void
+builtin_session_reset_callback (stream_session_t * s)
+{
+  clib_warning ("called.. ");
+
+  stream_session_cleanup (s);
+}
+
+
+static int
+builtin_session_connected_callback (u32 app_index, u32 api_context,
+				    stream_session_t * s, u8 is_fail)
+{
+  clib_warning ("called...");
+  return -1;
+}
+
+static int
+builtin_add_segment_callback (u32 client_index,
+			      const u8 * seg_name, u32 seg_size)
+{
+  clib_warning ("called...");
+  return -1;
+}
+
+static int
+builtin_redirect_connect_callback (u32 client_index, void *mp)
+{
+  clib_warning ("called...");
+  return -1;
+}
+
+static int
+http_server_rx_callback (stream_session_t * s)
+{
+  u32 max_dequeue;
+  int actual_transfer;
+  http_server_main_t *hsm = &http_server_main;
+  svm_fifo_t *rx_fifo;
+
+  rx_fifo = s->server_rx_fifo;
+
+  max_dequeue = svm_fifo_max_dequeue (rx_fifo);
+
+  svm_fifo_unset_event (rx_fifo);
+
+  if (PREDICT_FALSE (max_dequeue == 0))
+    return 0;
+
+  vec_validate (hsm->rx_buf, max_dequeue - 1);
+  _vec_len (hsm->rx_buf) = max_dequeue;
+
+  actual_transfer = svm_fifo_dequeue_nowait (rx_fifo, max_dequeue,
+					     hsm->rx_buf);
+  ASSERT (actual_transfer > 0);
+
+  _vec_len (hsm->rx_buf) = actual_transfer;
+
+  /* send the command to a new/recycled vlib process */
+  s->opaque[1] = (u64) vec_dup (hsm->rx_buf);
+
+  alloc_http_process (s);
+  return 0;
+}
+
+static session_cb_vft_t builtin_session_cb_vft = {
+  .session_accept_callback = builtin_session_accept_callback,
+  .session_disconnect_callback = builtin_session_disconnect_callback,
+  .session_connected_callback = builtin_session_connected_callback,
+  .add_segment_callback = builtin_add_segment_callback,
+  .redirect_connect_callback = builtin_redirect_connect_callback,
+  .builtin_server_rx_callback = http_server_rx_callback,
+  .session_reset_callback = builtin_session_reset_callback
+};
+
+/* Abuse VPP's input queue */
+static int
+create_api_loopback (vlib_main_t * vm)
+{
+  http_server_main_t *hsm = &http_server_main;
+  vl_api_memclnt_create_t _m, *mp = &_m;
+  extern void vl_api_memclnt_create_t_handler (vl_api_memclnt_create_t *);
+  api_main_t *am = &api_main;
+  vl_shmem_hdr_t *shmem_hdr;
+  uword *event_data = 0, event_type;
+  int resolved = 0;
+
+  /*
+   * Create a "loopback" API client connection
+   * Don't do things like this unless you know what you're doing...
+   */
+
+  shmem_hdr = am->shmem_hdr;
+  hsm->vl_input_queue = shmem_hdr->vl_input_queue;
+  memset (mp, 0, sizeof (*mp));
+  mp->_vl_msg_id = VL_API_MEMCLNT_CREATE;
+  mp->context = 0xFEEDFACE;
+  mp->input_queue = (u64) hsm->vl_input_queue;
+  strncpy ((char *) mp->name, "tcp_http_server", sizeof (mp->name) - 1);
+
+  vl_api_memclnt_create_t_handler (mp);
+
+  /* Wait for reply */
+  hsm->node_index = vlib_get_current_process (vm)->node_runtime.node_index;
+  vlib_process_wait_for_event_or_clock (vm, 1.0);
+  event_type = vlib_process_get_events (vm, &event_data);
+  switch (event_type)
+    {
+    case 1:
+      resolved = 1;
+      break;
+    case ~0:
+      /* timed out */
+      break;
+    default:
+      clib_warning ("unknown event_type %d", event_type);
+    }
+  if (!resolved)
+    return -1;
+
+  return 0;
+}
+
+static int
+server_attach ()
+{
+  http_server_main_t *hsm = &http_server_main;
+  u8 segment_name[128];
+  u64 options[SESSION_OPTIONS_N_OPTIONS];
+  vnet_app_attach_args_t _a, *a = &_a;
+
+  memset (a, 0, sizeof (*a));
+  memset (options, 0, sizeof (options));
+
+  a->api_client_index = hsm->my_client_index;
+  a->session_cb_vft = &builtin_session_cb_vft;
+  a->options = options;
+  a->options[SESSION_OPTIONS_SEGMENT_SIZE] = 128 << 20;
+  a->options[SESSION_OPTIONS_RX_FIFO_SIZE] = 8 << 10;
+  a->options[SESSION_OPTIONS_TX_FIFO_SIZE] = 32 << 10;
+  a->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP;
+  a->segment_name = segment_name;
+  a->segment_name_length = ARRAY_LEN (segment_name);
+
+  if (vnet_application_attach (a))
+    {
+      clib_warning ("failed to attach server");
+      return -1;
+    }
+  hsm->app_index = a->app_index;
+  return 0;
+}
+
+static int
+server_listen ()
+{
+  http_server_main_t *hsm = &http_server_main;
+  vnet_bind_args_t _a, *a = &_a;
+  memset (a, 0, sizeof (*a));
+  a->app_index = hsm->app_index;
+  a->uri = "tcp://0.0.0.0/80";
+  return vnet_bind_uri (a);
+}
+
+static int
+server_create (vlib_main_t * vm)
+{
+  http_server_main_t *hsm = &http_server_main;
+  u32 num_threads;
+  vlib_thread_main_t *vtm = vlib_get_thread_main ();
+
+  if (hsm->my_client_index == (u32) ~ 0)
+    {
+      if (create_api_loopback (vm))
+	return -1;
+    }
+
+  num_threads = 1 /* main thread */  + vtm->n_threads;
+  vec_validate (http_server_main.vpp_queue, num_threads - 1);
+
+  if (server_attach ())
+    {
+      clib_warning ("failed to attach server");
+      return -1;
+    }
+  if (server_listen ())
+    {
+      clib_warning ("failed to start listening");
+      return -1;
+    }
+  return 0;
+}
+
+/* Get our api client index */
+static void
+vl_api_memclnt_create_reply_t_handler (vl_api_memclnt_create_reply_t * mp)
+{
+  vlib_main_t *vm = vlib_get_main ();
+  http_server_main_t *hsm = &http_server_main;
+  hsm->my_client_index = mp->index;
+  vlib_process_signal_event (vm, hsm->node_index, 1 /* evt */ ,
+			     0 /* data */ );
+}
+
+#define foreach_tcp_http_server_api_msg      		\
+_(MEMCLNT_CREATE_REPLY, memclnt_create_reply)   		\
+
+static clib_error_t *
+tcp_http_server_api_hookup (vlib_main_t * vm)
+{
+  vl_msg_api_msg_config_t _c, *c = &_c;
+
+  /* Hook up client-side static APIs to our handlers */
+#define _(N,n) do {                                             \
+    c->id = VL_API_##N;                                         \
+    c->name = #n;                                               \
+    c->handler = vl_api_##n##_t_handler;                        \
+    c->cleanup = vl_noop_handler;                               \
+    c->endian = vl_api_##n##_t_endian;                          \
+    c->print = vl_api_##n##_t_print;                            \
+    c->size = sizeof(vl_api_##n##_t);                           \
+    c->traced = 1; /* trace, so these msgs print */             \
+    c->replay = 0; /* don't replay client create/delete msgs */ \
+    c->message_bounce = 0; /* don't bounce this message */	\
+    vl_msg_api_config(c);} while (0);
+
+  foreach_tcp_http_server_api_msg;
+#undef _
+
+  return 0;
+}
+
+static clib_error_t *
+server_create_command_fn (vlib_main_t * vm,
+			  unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  int rv;
+
+  tcp_http_server_api_hookup (vm);
+  vnet_session_enable_disable (vm, 1 /* turn on TCP, etc. */ );
+  rv = server_create (vm);
+  switch (rv)
+    {
+    case 0:
+      break;
+    default:
+      return clib_error_return (0, "server_create returned %d", rv);
+    }
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (server_create_command, static) =
+{
+  .path = "test http server",
+  .short_help = "test http server",
+  .function = server_create_command_fn,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+builtin_http_server_main_init (vlib_main_t * vm)
+{
+  http_server_main_t *hsm = &http_server_main;
+  hsm->my_client_index = ~0;
+  hsm->vlib_main = vm;
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (builtin_http_server_main_init);
+
+/*
+* fd.io coding-style-patch-verification: ON
+*
+* Local Variables:
+* eval: (c-set-style "gnu")
+* End:
+*/