summaryrefslogtreecommitdiffstats
path: root/src/vnet/fib/ip4_fib.c
blob: 0eff8d0d485e7f94146464131653ef8b271ba91a (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
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
/*
 * Copyright (c) 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.
 */

#include <vnet/fib/fib_table.h>
#include <vnet/fib/fib_entry.h>
#include <vnet/fib/ip4_fib.h>

/*
 * A table of prefixes to be added to tables and the sources for them
 */
typedef struct ip4_fib_table_special_prefix_t_ {
    fib_prefix_t ift_prefix;
    fib_source_t ift_source;
    fib_entry_flag_t ift_flag;
} ip4_fib_table_special_prefix_t;

static const ip4_fib_table_special_prefix_t ip4_specials[] = {
    {
	/* 0.0.0.0/0*/
	.ift_prefix = {
	    .fp_addr = {
		.ip4.data_u32 = 0,
	    },
	    .fp_len  = 0,
	    .fp_proto = FIB_PROTOCOL_IP4,
	},
	.ift_source = FIB_SOURCE_DEFAULT_ROUTE,
	.ift_flag   = FIB_ENTRY_FLAG_DROP,
    },
    {
	/* 0.0.0.0/32*/
	.ift_prefix = {
	    .fp_addr = {
		.ip4.data_u32 = 0,
	    },
	    .fp_len  = 32,
	    .fp_proto = FIB_PROTOCOL_IP4,
	},
	.ift_source = FIB_SOURCE_DEFAULT_ROUTE,
	.ift_flag   = FIB_ENTRY_FLAG_DROP,
    },
    {
	/*
	 * 240.0.0.0/4
	 * drop class E
	 */
	.ift_prefix = {
	    .fp_addr = {
		.ip4.data_u32 = 0xf0000000,
	    },
	    .fp_len   = 4,
	    .fp_proto = FIB_PROTOCOL_IP4,
	},
	.ift_source = FIB_SOURCE_SPECIAL,
	.ift_flag   = FIB_ENTRY_FLAG_DROP,

    },
    {
	/*
	 * 224.0.0.0/4
	 * drop all mcast
	 */
	.ift_prefix = {
	    .fp_addr = {
		.ip4.data_u32 = 0xe0000000,
	    },
	    .fp_len   = 4,
	    .fp_proto = FIB_PROTOCOL_IP4,
	},
	.ift_source = FIB_SOURCE_SPECIAL,
	.ift_flag    = FIB_ENTRY_FLAG_DROP,
    },
    {
	/*
	 * 255.255.255.255/32
	 * drop, but we'll allow it to be usurped by the likes of DHCP
	 */
	.ift_prefix = {
	    .fp_addr = {
		.ip4.data_u32 = 0xffffffff,
	    },
	    .fp_len   = 32,
	    .fp_proto = FIB_PROTOCOL_IP4,
	},
	.ift_source = FIB_SOURCE_DEFAULT_ROUTE,
	.ift_flag   = FIB_ENTRY_FLAG_DROP,
    }
};

void
ip4_fib_hash_load_specials (u32 fib_index)
{
    /*
     * add the special entries into the new FIB
     */
    int ii;

    for (ii = 0; ii < ARRAY_LEN(ip4_specials); ii++)
    {
	fib_prefix_t prefix = ip4_specials[ii].ift_prefix;

	prefix.fp_addr.ip4.data_u32 =
	    clib_host_to_net_u32(prefix.fp_addr.ip4.data_u32);

	fib_table_entry_special_add(fib_index,
				    &prefix,
				    ip4_specials[ii].ift_source,
				    ip4_specials[ii].ift_flag);
    }
}

void
ip4_fib_hash_flush_specials (u32 fib_index)
{
    int ii;

    /*
     * remove all the specials we added when the table was created.
     * In reverse order so the default route is last.
     */
    for (ii = ARRAY_LEN(ip4_specials) - 1; ii >= 0; ii--)
    {
	fib_prefix_t prefix = ip4_specials[ii].ift_prefix;

	prefix.fp_addr.ip4.data_u32 =
	    clib_host_to_net_u32(prefix.fp_addr.ip4.data_u32);

	fib_table_entry_special_remove(fib_index,
				       &prefix,
				       ip4_specials[ii].ift_source);
    }
}

static u32
ip4_create_fib_with_table_id (u32 table_id,
                              fib_source_t src)
{
    fib_table_t *fib_table;
    ip4_fib_t *v4_fib;

    pool_get(ip4_main.fibs, fib_table);
    clib_memset(fib_table, 0, sizeof(*fib_table));

    pool_get_aligned(ip4_fibs, v4_fib, CLIB_CACHE_LINE_BYTES);

    fib_table->ft_proto = FIB_PROTOCOL_IP4;
    fib_table->ft_index = (v4_fib - ip4_fibs);

    /*
     * It is required that the index of the fib_table_t in its pool
     * is the same as the index of the ip4_fib_t in its pool, since the
     * rest of the code usues the 'fib_index' to mean either of these
     * objects, depending on the context.
     */
    ASSERT(fib_table->ft_index == fib_table - ip4_main.fibs);

    hash_set (ip4_main.fib_index_by_table_id, table_id, fib_table->ft_index);

    fib_table->ft_table_id =
	v4_fib->hash.table_id =
	    table_id;
    fib_table->ft_flow_hash_config = IP_FLOW_HASH_DEFAULT;

    fib_table_lock(fib_table->ft_index, FIB_PROTOCOL_IP4, src);

    ip4_fib_table_init(v4_fib);

    /*
     * add the special entries into the new FIB
     */
    ip4_fib_hash_load_specials(fib_table - ip4_main.fibs);

    return (fib_table->ft_index);
}

void
ip4_fib_table_destroy (u32 fib_index)
{
    fib_table_t *fib_table = pool_elt_at_index(ip4_main.fibs, fib_index);
    ip4_fib_t *v4_fib = pool_elt_at_index(ip4_fibs, fib_table->ft_index);
    u32 *n_locks;

    /*
     * remove all the specials we added when the table was created.
     * In reverse order so the default route is last.
     */
    ip4_fib_hash_flush_specials(fib_table - ip4_main.fibs);

    /*
     * validate no more routes.
     */
#if CLIB_DEBUG > 0
    if (0 != fib_table->ft_total_route_counts)
        fib_table_assert_empty(fib_table);
#endif

    vec_foreach(n_locks, fib_table->ft_src_route_counts)
    {
	ASSERT(0 == *n_locks);
    }

    if (~0 != fib_table->ft_table_id)
    {
	hash_unset (ip4_main.fib_index_by_table_id, fib_table->ft_table_id);
    }

    vec_free (fib_table->ft_locks);
    vec_free(fib_table->ft_src_route_counts);
    ip4_fib_table_free(v4_fib);

    pool_put(ip4_fibs, v4_fib);
    pool_put(ip4_main.fibs, fib_table);
}


u32
ip4_fib_table_find_or_create_and_lock (u32 table_id,
                                       fib_source_t src)
{
    u32 index;

    index = ip4_fib_index_from_table_id(table_id);
    if (~0 == index)
	return ip4_create_fib_with_table_id(table_id, src);

    fib_table_lock(index, FIB_PROTOCOL_IP4, src);

    return (index);
}

u32
ip4_fib_table_create_and_lock (fib_source_t src)
{
    return (ip4_create_fib_with_table_id(~0, src));
}

u32
ip4_fib_table_get_index_for_sw_if_index (u32 sw_if_index)
{
    if (sw_if_index >= vec_len(ip4_main.fib_index_by_sw_if_index))
    {
	/*
	 * This is the case for interfaces that are not yet mapped to
	 * a IP table
	 */
	return (~0);
    }
    return (ip4_main.fib_index_by_sw_if_index[sw_if_index]);
}


/**
 * Walk show context
 */
typedef struct ip4_fib_show_walk_ctx_t_
{
    fib_node_index_t *ifsw_indicies;
} ip4_fib_show_walk_ctx_t;

static fib_table_walk_rc_t
ip4_fib_show_walk_cb (fib_node_index_t fib_entry_index,
                      void *arg)
{
    ip4_fib_show_walk_ctx_t *ctx = arg;

    vec_add1(ctx->ifsw_indicies, fib_entry_index);

    return (FIB_TABLE_WALK_CONTINUE);
}

static void
ip4_fib_table_show_all (ip4_fib_t *fib,
			vlib_main_t * vm)
{
    ip4_fib_show_walk_ctx_t ctx = {
        .ifsw_indicies = NULL,
    };
    fib_node_index_t *fib_entry_index;

    ip4_fib_table_walk(fib, ip4_fib_show_walk_cb, &ctx);
    vec_sort_with_function(ctx.ifsw_indicies,
                           fib_entry_cmp_for_sort);

    vec_foreach(fib_entry_index, ctx.ifsw_indicies)
    {
	vlib_cli_output(vm, "%U",
                        format_fib_entry,
                        *fib_entry_index,
                        FIB_ENTRY_FORMAT_BRIEF);
    }

    vec_free(ctx.ifsw_indicies);
}

static void
ip4_fib_table_show_one (ip4_fib_t *fib,
			vlib_main_t * vm,
			ip4_address_t *address,
			u32 mask_len,
                        int detail)
{
    vlib_cli_output(vm, "%U",
                    format_fib_entry,
                    ip4_fib_table_lookup(fib, address, mask_len),
                    (detail ?
                     FIB_ENTRY_FORMAT_DETAIL2 :
                     FIB_ENTRY_FORMAT_DETAIL));
}

u8 *
format_ip4_fib_table_memory (u8 * s, va_list * args)
{
    s = format(s, "%=30s %=6d\n",
               "IPv4 unicast",
               pool_elts(ip4_main.fibs));
    return (s);
}

static clib_error_t *
ip4_show_fib (vlib_main_t * vm,
	      unformat_input_t * input,
	      vlib_cli_command_t * cmd)
{
    ip4_main_t * im4 = &ip4_main;
    u64 total_mtrie_memory, total_hash_memory;
    int verbose, matching, mtrie, memory;
    ip4_address_t matching_address;
    u32 fib_index, matching_mask = 32;
    int i, table_id = -1, user_fib_index = ~0;
    int detail = 0;

    verbose = 1;
    matching = mtrie = memory = 0;
    total_hash_memory = total_mtrie_memory = 0;

    while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
	if (unformat (input, "brief") || unformat (input, "summary")
	    || unformat (input, "sum"))
	    verbose = 0;

	else if (unformat (input, "detail") || unformat (input, "det"))
	    detail = 1;

	else if (unformat (input, "mtrie"))
	    mtrie = 1;

        else if (unformat (input, "mem") ||
                 unformat (input, "memory"))
	    memory = 1;

	else if (unformat (input, "%U/%d",
			   unformat_ip4_address, &matching_address, &matching_mask))
	    matching = 1;

	else if (unformat (input, "%U", unformat_ip4_address, &matching_address))
	    matching = 1;

	else if (unformat (input, "table %d", &table_id))
	    ;
	else if (unformat (input, "index %d", &user_fib_index))
	    ;
	else
	    break;
    }

    pool_foreach_index (fib_index, im4->fibs)
     {
	fib_table_t *fib_table = pool_elt_at_index(im4->fibs, fib_index);
	ip4_fib_t *fib = pool_elt_at_index(ip4_fibs, fib_table->ft_index);
        fib_source_t source;
        u8 *s = NULL;

	if (table_id >= 0 && table_id != (int)fib->hash.table_id)
	    continue;
	if (user_fib_index != ~0 && user_fib_index != fib_index)
	    continue;

        if (memory)
        {
            uword mtrie_size, hash_size;


            mtrie_size = ip4_mtrie_memory_usage(&fib->mtrie);
            hash_size = 0;

	    for (i = 0; i < ARRAY_LEN (fib->hash.fib_entry_by_dst_address); i++)
	    {
		uword * hash = fib->hash.fib_entry_by_dst_address[i];
                if (NULL != hash)
                {
                    hash_size += hash_bytes(hash);
                }
            }

            if (verbose)
                vlib_cli_output (vm, "%U mtrie:%d hash:%d",
                                 format_fib_table_name, fib_index,
                                 FIB_PROTOCOL_IP4,
                                 mtrie_size,
                                 hash_size);
            total_mtrie_memory += mtrie_size;
            total_hash_memory += hash_size;
            continue;
        }

	s = format(s, "%U, fib_index:%d, flow hash:[%U] epoch:%d flags:%U locks:[",
                   format_fib_table_name, fib_index,
                   FIB_PROTOCOL_IP4,
                   fib_index,
                   format_ip_flow_hash_config,
                   fib_table->ft_flow_hash_config,
                   fib_table->ft_epoch,
                   format_fib_table_flags, fib_table->ft_flags);
        vec_foreach_index(source, fib_table->ft_locks)
        {
            if (0 != fib_table->ft_locks[source])
            {
                s = format(s, "%U:%d, ",
                           format_fib_source, source,
                           fib_table->ft_locks[source]);
            }
        }
        s = format (s, "]");
        vlib_cli_output (vm, "%v", s);
        vec_free(s);

	/* Show summary? */
	if (mtrie)
        {
	    vlib_cli_output (vm, "%U", format_ip4_mtrie, &fib->mtrie, verbose);
            continue;
        }
	if (! verbose)
	{
	    vlib_cli_output (vm, "%=20s%=16s", "Prefix length", "Count");
	    for (i = 0; i < ARRAY_LEN (fib->hash.fib_entry_by_dst_address); i++)
	    {
		uword * hash = fib->hash.fib_entry_by_dst_address[i];
		uword n_elts = hash_elts (hash);
		if (n_elts > 0)
		    vlib_cli_output (vm, "%20d%16d", i, n_elts);
	    }
	    continue;
	}

	if (!matching)
	{
	    ip4_fib_table_show_all(fib, vm);
	}
	else
	{
	    ip4_fib_table_show_one(fib, vm, &matching_address,
                                   matching_mask, detail);
	}
    }

    if (memory)
    {
        vlib_cli_output (vm, "totals: mtrie:%ld hash:%ld all:%ld",
                         total_mtrie_memory,
                         total_hash_memory,
                         total_mtrie_memory + total_hash_memory);
    }
    return 0;
}

/*?
 * This command displays the IPv4 FIB Tables (VRF Tables) and the route
 * entries for each table.
 *
 * @note This command will run for a long time when the FIB tables are
 * comprised of millions of entries. For those scenarios, consider displaying
 * a single table or summary mode.
 *
 * @cliexpar
 * Example of how to display all the IPv4 FIB tables:
 * @cliexstart{show ip fib}
 * ipv4-VRF:0, fib_index 0, flow hash: src dst sport dport proto
 * 0.0.0.0/0
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:0 buckets:1 uRPF:0 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 0.0.0.0/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:1 buckets:1 uRPF:1 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 6.0.1.2/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:30 buckets:1 uRPF:29 to:[0:0]]
 *     [0] [@3]: arp-ipv4: via 6.0.0.1 af_packet0
 * 7.0.0.1/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:31 buckets:4 uRPF:30 to:[0:0]]
 *     [0] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
 *     [1] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
 *     [2] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
 *     [3] [@3]: arp-ipv4: via 6.0.0.1 af_packet0
 * 224.0.0.0/8
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:3 buckets:1 uRPF:3 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 240.0.0.0/8
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:2 buckets:1 uRPF:2 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 255.255.255.255/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:4 buckets:1 uRPF:4 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
 * 0.0.0.0/0
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:12 buckets:1 uRPF:11 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 0.0.0.0/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:13 buckets:1 uRPF:12 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 172.16.1.0/24
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:17 buckets:1 uRPF:16 to:[0:0]]
 *     [0] [@4]: ipv4-glean: af_packet0
 * 172.16.1.1/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:18 buckets:1 uRPF:17 to:[1:84]]
 *     [0] [@2]: dpo-receive: 172.16.1.1 on af_packet0
 * 172.16.1.2/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:21 buckets:1 uRPF:20 to:[0:0]]
 *     [0] [@5]: ipv4 via 172.16.1.2 af_packet0: IP4: 02:fe:9e:70:7a:2b -> 26:a5:f6:9c:3a:36
 * 172.16.2.0/24
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:19 buckets:1 uRPF:18 to:[0:0]]
 *     [0] [@4]: ipv4-glean: af_packet1
 * 172.16.2.1/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:20 buckets:1 uRPF:19 to:[0:0]]
 *     [0] [@2]: dpo-receive: 172.16.2.1 on af_packet1
 * 224.0.0.0/8
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:15 buckets:1 uRPF:14 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 240.0.0.0/8
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:14 buckets:1 uRPF:13 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 255.255.255.255/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:16 buckets:1 uRPF:15 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * @cliexend
 * Example of how to display a single IPv4 FIB table:
 * @cliexstart{show ip fib table 7}
 * ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
 * 0.0.0.0/0
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:12 buckets:1 uRPF:11 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 0.0.0.0/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:13 buckets:1 uRPF:12 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 172.16.1.0/24
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:17 buckets:1 uRPF:16 to:[0:0]]
 *     [0] [@4]: ipv4-glean: af_packet0
 * 172.16.1.1/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:18 buckets:1 uRPF:17 to:[1:84]]
 *     [0] [@2]: dpo-receive: 172.16.1.1 on af_packet0
 * 172.16.1.2/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:21 buckets:1 uRPF:20 to:[0:0]]
 *     [0] [@5]: ipv4 via 172.16.1.2 af_packet0: IP4: 02:fe:9e:70:7a:2b -> 26:a5:f6:9c:3a:36
 * 172.16.2.0/24
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:19 buckets:1 uRPF:18 to:[0:0]]
 *     [0] [@4]: ipv4-glean: af_packet1
 * 172.16.2.1/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:20 buckets:1 uRPF:19 to:[0:0]]
 *     [0] [@2]: dpo-receive: 172.16.2.1 on af_packet1
 * 224.0.0.0/8
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:15 buckets:1 uRPF:14 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 240.0.0.0/8
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:14 buckets:1 uRPF:13 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * 255.255.255.255/32
 *   unicast-ip4-chain
 *   [@0]: dpo-load-balance: [index:16 buckets:1 uRPF:15 to:[0:0]]
 *     [0] [@0]: dpo-drop ip6
 * @cliexend
 * Example of how to display a summary of all IPv4 FIB tables:
 * @cliexstart{show ip fib summary}
 * ipv4-VRF:0, fib_index 0, flow hash: src dst sport dport proto
 *     Prefix length         Count
 *                    0               1
 *                    8               2
 *                   32               4
 * ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
 *     Prefix length         Count
 *                    0               1
 *                    8               2
 *                   24               2
 *                   32               4
 * @cliexend
 ?*/
VLIB_CLI_COMMAND (ip4_show_fib_command, static) = {
    .path = "show ip fib",
    .short_help = "show ip fib [summary] [table <table-id>] [index <fib-id>] [<ip4-addr>[/<mask>]] [mtrie] [detail]",
    .function = ip4_show_fib,
};

static clib_error_t *
ip_config (vlib_main_t * vm, unformat_input_t * input)
{
    char *default_name = 0;

    while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
	if (unformat (input, "default-table-name %s", &default_name))
	    ;
	else
	    return clib_error_return (0, "unknown input '%U'",
				      format_unformat_error, input);
    }

    fib_table_default_names[FIB_PROTOCOL_IP4] = default_name;

    return 0;
}

VLIB_EARLY_CONFIG_FUNCTION (ip_config, "ip");