summaryrefslogtreecommitdiffstats
path: root/nest/rt-attr.c
blob: c16d08ba75cefc94693589ed48101425fe4bdbed (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
/*
 *	BIRD -- Route Attribute Cache
 *
 *	(c) 1998--2000 Martin Mares <mj@ucw.cz>
 *
 *	Can be freely distributed and used under the terms of the GNU GPL.
 */

#include <alloca.h>

#include "nest/bird.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "nest/iface.h"
#include "nest/cli.h"
#include "nest/attrs.h"
#include "lib/resource.h"
#include "lib/string.h"

static slab *rta_slab;
static pool *rta_pool;

struct protocol *attr_class_to_protocol[EAP_MAX];

/*
 *	Extended Attributes
 */

static inline eattr *
ea__find(ea_list *e, unsigned id)
{
  eattr *a;
  int l, r, m;

  while (e)
    {
      if (e->flags & EALF_BISECT)
	{
	  l = 0;
	  r = e->count + 1;
	  while (l <= r)
	    {
	      m = (l+r) / 2;
	      a = &e->attrs[m];
	      if (a->id == id)
		return a;
	      else if (a->id < id)
		l = m+1;
	      else
		r = m-1;
	    }
	}
      else
	for(m=0; m<e->count; m++)
	  if (e->attrs[m].id == id)
	    return &e->attrs[m];
      e = e->next;
    }
  return NULL;
}

eattr *
ea_find(ea_list *e, unsigned id)
{
  eattr *a = ea__find(e, id & EA_CODE_MASK);

  if (a && (a->type & EAF_TYPE_MASK) == EAF_TYPE_UNDEF &&
      !(id & EA_ALLOW_UNDEF))
    return NULL;
  return a;
}

static inline void
ea_do_sort(ea_list *e)
{
  unsigned n = e->count;
  eattr *a = e->attrs;
  eattr *b = alloca(n * sizeof(eattr));
  unsigned s, ss;

  /* We need to use a stable sorting algorithm, hence mergesort */
  do
    {
      s = ss = 0;
      while (s < n)
	{
	  eattr *p, *q, *lo, *hi;
	  p = b;
	  ss = s;
	  *p++ = a[s++];
	  while (s < n && p[-1].id <= a[s].id)
	    *p++ = a[s++];
	  if (s < n)
	    {
	      q = p;
	      *p++ = a[s++];
	      while (s < n && p[-1].id <= a[s].id)
		*p++ = a[s++];
	      lo = b;
	      hi = q;
	      s = ss;
	      while (lo < q && hi < p)
		if (lo->id <= hi->id)
		  a[s++] = *lo++;
		else
		  a[s++] = *hi++;
	      while (lo < q)
		a[s++] = *lo++;
	      while (hi < p)
		a[s++] = *hi++;
	    }
	}
    }
  while (ss);
}

static inline void
ea_do_prune(ea_list *e)
{
  eattr *s, *d, *l;
  int i = 0;

  /* Discard duplicates and undefs. Do you remember sorting was stable? */
  s = d = e->attrs;
  l = e->attrs + e->count;
  while (s < l)
    {
      if ((s->type & EAF_TYPE_MASK) != EAF_TYPE_UNDEF)
	{
	  *d++ = *s;
	  i++;
	}
      s++;
      while (s < l && s->id == s[-1].id)
	s++;
    }
  e->count = i;
}

void
ea_sort(ea_list *e)
{
  while (e)
    {
      if (!(e->flags & EALF_SORTED))
	{
	  ea_do_sort(e);
	  ea_do_prune(e);
	  e->flags |= EALF_SORTED;
	}
      if (e->count > 5)
	e->flags |= EALF_BISECT;
      e = e->next;
    }
}

unsigned
ea_scan(ea_list *e)
{
  unsigned cnt = 0;

  while (e)
    {
      cnt += e->count;
      e = e->next;
    }
  return sizeof(ea_list) + sizeof(eattr)*cnt;
}

void
ea_merge(ea_list *e, ea_list *t)
{
  eattr *d = t->attrs;

  t->flags = 0;
  t->count = 0;
  t->next = NULL;
  while (e)
    {
      memcpy(d, e->attrs, sizeof(eattr)*e->count);
      t->count += e->count;
      d += e->count;
      e = e->next;
    }
}

int
ea_same(ea_list *x, ea_list *y)
{
  int c;

  if (!x || !y)
    return x == y;
  ASSERT(!x->next && !y->next);
  if (x->count != y->count)
    return 0;
  for(c=0; c<x->count; c++)
    {
      eattr *a = &x->attrs[c];
      eattr *b = &y->attrs[c];

      if (a->id != b->id ||
	  a->flags != b->flags ||
	  a->type != b->type ||
	  ((a->type & EAF_EMBEDDED) ? a->u.data != b->u.data :
	   (a->u.ptr->length != b->u.ptr->length || memcmp(a->u.ptr, b->u.ptr, a->u.ptr->length))))
	return 0;
    }
  return 1;
}

static inline ea_list *
ea_list_copy(ea_list *o)
{
  ea_list *n;
  unsigned i, len;

  if (!o)
    return NULL;
  ASSERT(!o->next);
  len = sizeof(ea_list) + sizeof(eattr) * o->count;
  n = mb_alloc(rta_pool, len);
  memcpy(n, o, len);
  n->flags |= EALF_CACHED;
  for(i=0; i<o->count; i++)
    {
      eattr *a = &n->attrs[i];
      if (!(a->type & EAF_EMBEDDED))
	{
	  unsigned size = sizeof(struct adata) + a->u.ptr->length;
	  struct adata *d = mb_alloc(rta_pool, size);
	  memcpy(d, a->u.ptr, size);
	  a->u.ptr = d;
	}
    }
  return n;
}

void
ea_format(eattr *e, byte *buf)
{
  struct protocol *p;
  int status = GA_UNKNOWN;
  unsigned int i;
  struct adata *ad = (e->type & EAF_EMBEDDED) ? NULL : e->u.ptr;
  byte *end = buf + EA_FORMAT_BUF_SIZE - 1;

  if (p = attr_class_to_protocol[EA_PROTO(e->id)])
    {
      buf += bsprintf(buf, "%s.", p->name);
      if (p->get_attr)
	status = p->get_attr(e, buf);
      buf += strlen(buf);
    }
  else if (EA_PROTO(e->id))
    buf += bsprintf(buf, "%02x.", EA_PROTO(e->id));
  if (status < GA_NAME)
    buf += bsprintf(buf, "%02x", EA_ID(e->id));
  if (status < GA_FULL)
    {
      *buf++ = ':';
      *buf++ = ' ';
      switch (e->type & EAF_TYPE_MASK)
	{
	case EAF_TYPE_INT:
	  bsprintf(buf, "%d", e->u.data);
	  break;
	case EAF_TYPE_OPAQUE:
	  for(i=0; i<ad->length; i++)
	    {
	      if (buf > end - 8)
		{
		  strcpy(buf, " ...");
		  break;
		}
	      if (i)
		*buf++ = ' ';
	      buf += bsprintf(buf, "%02x", ad->data[i]);
	    }
	  break;
	case EAF_TYPE_IP_ADDRESS:
	  bsprintf(buf, "%I", *(ip_addr *) ad->data);
	  break;
	case EAF_TYPE_ROUTER_ID:
	  bsprintf(buf, "%08x", e->u.data); /* FIXME: Better printing of router ID's */
	  break;
	case EAF_TYPE_AS_PATH:
	  as_path_format(ad, buf, end - buf);
	  break;
	case EAF_TYPE_INT_SET:
	  int_set_format(ad, buf, end - buf);
	  break;
	case EAF_TYPE_UNDEF:
	default:
	  bsprintf(buf, "<type %02x>", e->type);
	}
    }
}

void
ea_dump(ea_list *e)
{
  int i;

  if (!e)
    {
      debug("NONE");
      return;
    }
  while (e)
    {
      debug("[%c%c%c]",
	    (e->flags & EALF_SORTED) ? 'S' : 's',
	    (e->flags & EALF_BISECT) ? 'B' : 'b',
	    (e->flags & EALF_CACHED) ? 'C' : 'c');
      for(i=0; i<e->count; i++)
	{
	  eattr *a = &e->attrs[i];
	  debug(" %02x:%02x.%02x", EA_PROTO(a->id), EA_ID(a->id), a->flags);
	  if (a->type & EAF_TEMP)
	    debug("T");
	  debug("=%c", "?iO?I?P???S?????" [a->type & EAF_TYPE_MASK]);
	  if (a->type & EAF_EMBEDDED)
	    debug(":%08x", a->u.data);
	  else
	    {
	      int j, len = a->u.ptr->length;
	      debug("[%d]:", len);
	      for(j=0; j<len; j++)
		debug("%02x", a->u.ptr->data[j]);
	    }
	}
      if (e = e->next)
	debug(" | ");
    }
}

inline unsigned int
ea_hash(ea_list *e)
{
  u32 h = 0;
  int i;

  if (e)			/* Assuming chain of length 1 */
    {
      for(i=0; i<e->count; i++)
	{
	  struct eattr *a = &e->attrs[i];
	  h ^= a->id;
	  if (a->type & EAF_EMBEDDED)
	    h ^= a->u.data;
	  else
	    {
	      struct adata *d = a->u.ptr;
	      int size = d->length;
	      byte *z = d->data;
	      while (size >= 4)
		{
		  h ^= *(u32 *)z;
		  z += 4;
		  size -= 4;
		}
	      while (size--)
		h = (h >> 24) ^ (h << 8) ^ *z++;
	    }
	}
      h ^= h >> 16;
      h ^= h >> 6;
      h &= 0xffff;
    }
  return h;
}

/*
 *	rta's
 */

static unsigned int rta_cache_count;
static unsigned int rta_cache_size = 32;
static unsigned int rta_cache_limit;
static unsigned int rta_cache_mask;
static rta **rta_hash_table;

static void
rta_alloc_hash(void)
{
  rta_hash_table = mb_alloc(rta_pool, sizeof(rta *) * rta_cache_size);
  bzero(rta_hash_table, sizeof(rta *) * rta_cache_size);
  if (rta_cache_size < 32768)
    rta_cache_limit = rta_cache_size * 2;
  else
    rta_cache_limit = ~0;
  rta_cache_mask = rta_cache_size - 1;
}

static inline unsigned int
rta_hash(rta *a)
{
  return a->proto->hash_key ^ ipa_hash(a->gw) ^ ea_hash(a->eattrs);
}

static inline int
rta_same(rta *x, rta *y)
{
  return (x->proto == y->proto &&
	  x->source == y->source &&
	  x->scope == y->scope &&
	  x->cast == y->cast &&
	  x->dest == y->dest &&
	  x->flags == y->flags &&
	  ipa_equal(x->gw, y->gw) &&
	  ipa_equal(x->from, y->from) &&
	  x->iface == y->iface &&
	  ea_same(x->eattrs, y->eattrs));
}

static rta *
rta_copy(rta *o)
{
  rta *r = sl_alloc(rta_slab);

  memcpy(r, o, sizeof(rta));
  r->uc = 1;
  r->eattrs = ea_list_copy(o->eattrs);
  return r;
}

static inline void
rta_insert(rta *r)
{
  unsigned int h = r->hash_key & rta_cache_mask;
  r->next = rta_hash_table[h];
  if (r->next)
    r->next->pprev = &r->next;
  r->pprev = &rta_hash_table[h];
  rta_hash_table[h] = r;
}

static void
rta_rehash(void)
{
  unsigned int ohs = rta_cache_size;
  unsigned int h;
  rta *r, *n;
  rta **oht = rta_hash_table;

  rta_cache_size = 2*rta_cache_size;
  DBG("Rehashing rta cache from %d to %d entries.\n", ohs, rta_cache_size);
  rta_alloc_hash();
  for(h=0; h<ohs; h++)
    for(r=oht[h]; r; r=n)
      {
	n = r->next;
	rta_insert(r);
      }
  mb_free(oht);
}

rta *
rta_lookup(rta *o)
{
  rta *r;
  unsigned int h;

  ASSERT(!(o->aflags & RTAF_CACHED));
  if (o->eattrs)
    {
      if (o->eattrs->next)	/* Multiple ea_list's, need to merge them */
	{
	  ea_list *ml = alloca(ea_scan(o->eattrs));
	  ea_merge(o->eattrs, ml);
	  o->eattrs = ml;
	}
      ea_sort(o->eattrs);
    }

  h = rta_hash(o);
  for(r=rta_hash_table[h & rta_cache_mask]; r; r=r->next)
    if (r->hash_key == h && rta_same(r, o))
      return rta_clone(r);

  r = rta_copy(o);
  r->hash_key = h;
  r->aflags = RTAF_CACHED;
  rta_insert(r);

  if (++rta_cache_count > rta_cache_limit)
    rta_rehash();

  return r;
}

void
rta__free(rta *a)
{
  ASSERT(rta_cache_count && (a->aflags & RTAF_CACHED));
  rta_cache_count--;
}

void
rta_dump(rta *a)
{
  static char *rts[] = { "RTS_DUMMY", "RTS_STATIC", "RTS_INHERIT", "RTS_DEVICE",
			 "RTS_STAT_DEV", "RTS_REDIR", "RTS_RIP", "RTS_RIP_EXT",
			 "RTS_OSPF", "RTS_OSPF_EXT", "RTS_OSPF_IA",
			 "RTS_OSPF_BOUNDARY", "RTS_BGP" };
  static char *rtc[] = { "", " BC", " MC", " AC" };
  static char *rtd[] = { "", " DEV", " HOLE", " UNREACH", " PROHIBIT" };

  debug("p=%s uc=%d %s %s%s%s h=%04x",
	a->proto->name, a->uc, rts[a->source], ip_scope_text(a->scope), rtc[a->cast],
	rtd[a->dest], a->hash_key);
  if (!(a->aflags & RTAF_CACHED))
    debug(" !CACHED");
  debug(" <-%I", a->from);
  if (a->dest == RTD_ROUTER)
    debug(" ->%I", a->gw);
  if (a->dest == RTD_DEVICE || a->dest == RTD_ROUTER)
    debug(" [%s]", a->iface ? a->iface->name : "???" );
  if (a->eattrs)
    {
      debug(" EA: ");
      ea_dump(a->eattrs);
    }
}

void
rta_dump_all(void)
{
  rta *a;
  unsigned int h;

  debug("Route attribute cache (%d entries, rehash at %d):\n", rta_cache_count, rta_cache_limit);
  for(h=0; h<rta_cache_size; h++)
    for(a=rta_hash_table[h]; a; a=a->next)
      {
	debug("%p ", a);
	rta_dump(a);
	debug("\n");
      }
  debug("\n");
}

void
rta_show(struct cli *c, rta *a)
{
  static char *src_names[] = { "dummy", "static", "inherit", "device", "static-device", "redirect",
			       "RIP", "RIP-ext", "OSPF", "OSPF-ext", "OSPF-IA", "OSPF-boundary",
			       "BGP" };
  static char *cast_names[] = { "unicast", "broadcast", "multicast", "anycast" };
  ea_list *eal;
  int i;
  byte buf[EA_FORMAT_BUF_SIZE];

  cli_printf(c, -1008, "\tType: %s %s %s", src_names[a->source], cast_names[a->cast], ip_scope_text(a->scope));
  for(eal=a->eattrs; eal; eal=eal->next)
    for(i=0; i<eal->count; i++)
      {
	ea_format(&eal->attrs[i], buf);
	cli_printf(c, -1012, "\t%s", buf);
      }
}

void
rta_init(void)
{
  rta_pool = rp_new(&root_pool, "Attributes");
  rta_slab = sl_new(rta_pool, sizeof(rta));
  rta_alloc_hash();
}