summaryrefslogtreecommitdiffstats
path: root/src/plugins/lldp/lldp_node.c
blob: dbbb5d46402b3868acff22f83e4ef26e01d892d0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
/*
 * Copyright (c) 2011-2016 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.
 */
/**
 * @file
 * @brief LLDP nodes implementation
 */
#include <lldp/lldp_node.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/ethernet/packet.h>

/* set this to 1 to turn on debug prints via clib_warning() */
#define LLDP_DEBUG (0)

static vlib_node_registration_t lldp_process_node;

#define F(sym, string) static char LLDP_ERR_##sym##_STR[] = string;
foreach_lldp_error (F);
#undef F

/*
 * packet counter strings
 * Dump these counters via the "show error" CLI command
 */
static char *lldp_error_strings[] = {
#define F(sym, string) LLDP_ERR_##sym##_STR,
  foreach_lldp_error (F)
#undef F
};

/*
 * We actually send all lldp pkts to the "error" node after scanning
 * them, so the graph node has only one next-index. The "error-drop"
 * node automatically bumps our per-node packet counters for us.
 */
typedef enum
{
  LLDP_INPUT_NEXT_NORMAL,
  LLDP_INPUT_N_NEXT,
} lldp_next_t;

/*
 * Process a frame of lldp packets
 * Expect 1 packet / frame
 */
static uword
lldp_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
	      vlib_frame_t * frame)
{
  u32 n_left_from, *from;
  lldp_input_trace_t *t0;

  from = vlib_frame_vector_args (frame);	/* array of buffer indices */
  n_left_from = frame->n_vectors;	/* number of buffer indices */

  while (n_left_from > 0)
    {
      u32 bi0;
      vlib_buffer_t *b0;
      u32 next0, error0;

      bi0 = from[0];
      b0 = vlib_get_buffer (vm, bi0);

      next0 = LLDP_INPUT_NEXT_NORMAL;

      /* scan this lldp pkt. error0 is the counter index to bump */
      error0 = lldp_input (vm, b0, bi0);
      b0->error = node->errors[error0];

      /* If this pkt is traced, snapshot the data */
      if (b0->flags & VLIB_BUFFER_IS_TRACED)
	{
	  int len;
	  t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
	  len = (b0->current_length < sizeof (t0->data)) ? b0->current_length
	    : sizeof (t0->data);
	  t0->len = len;
	  clib_memcpy_fast (t0->data, vlib_buffer_get_current (b0), len);
	}
      /* push this pkt to the next graph node, always error-drop */
      vlib_set_next_frame_buffer (vm, node, next0, bi0);

      from += 1;
      n_left_from -= 1;
    }

  return frame->n_vectors;
}

/*
 * lldp input graph node declaration
 */
VLIB_REGISTER_NODE(lldp_input_node, static) = {
  .function = lldp_node_fn,
  .name = "lldp-input",
  .vector_size = sizeof(u32),
  .type = VLIB_NODE_TYPE_INTERNAL,

  .n_errors = LLDP_N_ERROR,
  .error_strings = lldp_error_strings,

  .format_trace = lldp_input_format_trace,

  .n_next_nodes = LLDP_INPUT_N_NEXT,
  .next_nodes =
      {
              [LLDP_INPUT_NEXT_NORMAL] = "error-drop",
      },
};

/*
 * lldp process node function
 */
static uword
lldp_process (vlib_main_t * vm, vlib_node_runtime_t * rt, vlib_frame_t * f)
{
  lldp_main_t *lm = &lldp_main;
  f64 timeout = 0;
  uword event_type, *event_data = 0;

  /* So we can send events to the lldp process */
  lm->lldp_process_node_index = lldp_process_node.index;

  /* with ethernet input */
  ethernet_register_input_type (vm, ETHERNET_TYPE_802_1_LLDP /* LLDP */ ,
				lldp_input_node.index);

  while (1)
    {
      if (vec_len (lm->intfs_timeouts))
	{
#if LLDP_DEBUG
	  clib_warning ("DEBUG: wait for event with timeout %f", timeout);
#endif
	  (void) vlib_process_wait_for_event_or_clock (vm, timeout);
	}
      else
	{
#if LLDP_DEBUG
	  clib_warning ("DEBUG: wait for event without timeout");
#endif
	  (void) vlib_process_wait_for_event (vm);
	}
      event_type = vlib_process_get_events (vm, &event_data);
      switch (event_type)
	{
	case ~0:		/* no events => timeout */
	  /* nothing to do here */
	  break;
	case LLDP_EVENT_RESCHEDULE:
	  /* nothing to do here - reschedule is done automatically after
	   * each event or timeout */
	  break;
	default:
	  clib_warning ("BUG: event type 0x%wx", event_type);
	  break;
	}
      if (!vec_len (lm->intfs_timeouts))
	{
	  continue;
	}
      /* send packet(s) and schedule another timeout */
      const f64 now = vlib_time_now (lm->vlib_main);
      while (1)
	{
	  lldp_intf_t *n = pool_elt_at_index (lm->intfs,
					      lm->intfs_timeouts
					      [lm->intfs_timeouts_idx]);
	  if (n->last_sent < 0.01 || now > n->last_sent + lm->msg_tx_interval)
	    {
#if LLDP_DEBUG
	      clib_warning ("send packet to lldp %p, if idx %d", n,
			    n->hw_if_index);
#endif
	      lldp_send_ethernet (lm, n, 0);
	      ++lm->intfs_timeouts_idx;
	      if (lm->intfs_timeouts_idx >= vec_len (lm->intfs_timeouts))
		{
		  lm->intfs_timeouts_idx = 0;
		}
	      continue;
	    }
	  else
	    {
	      timeout = n->last_sent + lm->msg_tx_interval - now;
	      break;
	    }
	}
#if LLDP_DEBUG
      clib_warning ("DEBUG: timeout set to %f", timeout);
      u8 *s = NULL;
      u32 i;
      vec_foreach_index (i, lm->intfs_timeouts)
      {
	if (i == lm->intfs_timeouts_idx)
	  {
	    s = format (s, " [%d]", lm->intfs_timeouts[i]);
	  }
	else
	  {
	    s = format (s, " %d", lm->intfs_timeouts[i]);
	  }
      }
      clib_warning ("DEBUG: timeout schedule: %s", s);
      vec_free (s);
#endif
      if (event_data)
	{
	  vec_set_len (event_data, 0);
	}
    }

  return 0;
}

/*
 * lldp process node declaration
 */
VLIB_REGISTER_NODE(lldp_process_node, static) = {
  .function = lldp_process,
  .type = VLIB_NODE_TYPE_PROCESS,
  .name = "lldp-process",
};

void
lldp_schedule_intf (lldp_main_t * lm, lldp_intf_t * n)
{
  const int idx = n - lm->intfs;
  u32 v;
  vec_foreach_index (v, lm->intfs_timeouts)
  {
    if (lm->intfs_timeouts[v] == idx)
      {
	/* already scheduled */
	return;
      }
  }
  n->last_sent = 0;		/* ensure that a packet is sent out immediately */
  /* put the interface at the current position in the timeouts - it
   * will timeout immediately */
  vec_insert (lm->intfs_timeouts, 1, lm->intfs_timeouts_idx);
  lm->intfs_timeouts[lm->intfs_timeouts_idx] = n - lm->intfs;
  vlib_process_signal_event (lm->vlib_main, lm->lldp_process_node_index,
			     LLDP_EVENT_RESCHEDULE, 0);
#if LLDP_DEBUG
  clib_warning ("DEBUG: schedule interface %p, if idx %d", n, n->hw_if_index);
#endif
}

void
lldp_unschedule_intf (lldp_main_t * lm, lldp_intf_t * n)
{
  if (!n)
    {
      return;
    }
#if LLDP_DEBUG
  clib_warning ("DEBUG: unschedule interface %p, if idx %d", n,
		n->hw_if_index);
#endif
  const int idx = n - lm->intfs;
  u32 v;
  /* remove intf index from timeouts vector */
  vec_foreach_index (v, lm->intfs_timeouts)
  {
    if (lm->intfs_timeouts[v] == idx)
      {
	vec_delete (lm->intfs_timeouts, 1, v);
	break;
      }
  }
  /* wrap current timeout index to first element if needed */
  if (lm->intfs_timeouts_idx >= vec_len (lm->intfs_timeouts))
    {
      lm->intfs_timeouts_idx = 0;
    }
  vlib_process_signal_event (lm->vlib_main, lm->lldp_process_node_index,
			     LLDP_EVENT_RESCHEDULE, 0);
}

static clib_error_t *
lldp_sw_interface_up_down (vnet_main_t * vnm, u32 sw_if_index, u32 flags)
{
  lldp_main_t *lm = &lldp_main;
  vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
  lldp_intf_t *n = lldp_get_intf (lm, hi->hw_if_index);
  if (n)
    {
      if (!(flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP))
	{
	  /* FIXME - the packet sent here isn't send properly - need to find a
	   * way to send the packet before interface goes down */
	  lldp_send_ethernet (lm, n, 1);
	  lldp_unschedule_intf (lm, n);
	}
    }
  return 0;
}

VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION (lldp_sw_interface_up_down);

static clib_error_t *
lldp_hw_interface_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
{
  lldp_main_t *lm = &lldp_main;
  lldp_intf_t *n = lldp_get_intf (lm, hw_if_index);
  if (n)
    {
      if (flags & VNET_HW_INTERFACE_FLAG_LINK_UP)
	{
	  lldp_schedule_intf (lm, n);
	}
    }
  return 0;
}

VNET_HW_INTERFACE_LINK_UP_DOWN_FUNCTION (lldp_hw_interface_up_down);

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