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[dragonfly.git] / sys / net / radix.c
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1/*
2 * Copyright (c) 1988, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)radix.c 8.4 (Berkeley) 11/2/94
34 * $FreeBSD: src/sys/net/radix.c,v 1.20.2.3 2002/04/28 05:40:25 suz Exp $
35 */
36
37/*
38 * Routines to build and maintain radix trees for routing lookups.
39 */
40#ifndef _RADIX_H_
41#include <sys/param.h>
42#ifdef _KERNEL
43#include <sys/systm.h>
44#include <sys/malloc.h>
45#define M_DONTWAIT M_NOWAIT
46#include <sys/domain.h>
47#else
48#include <stdlib.h>
49#endif
50#include <sys/syslog.h>
51#include <net/radix.h>
52#endif
53
54static int rn_walktree_from __P((struct radix_node_head *h, void *a,
55 void *m, walktree_f_t *f, void *w));
56static int rn_walktree __P((struct radix_node_head *, walktree_f_t *, void *));
57static struct radix_node
58 *rn_insert __P((void *, struct radix_node_head *, int *,
59 struct radix_node [2])),
60 *rn_newpair __P((void *, int, struct radix_node[2])),
61 *rn_search __P((void *, struct radix_node *)),
62 *rn_search_m __P((void *, struct radix_node *, void *));
63
64static int max_keylen;
65static struct radix_mask *rn_mkfreelist;
66static struct radix_node_head *mask_rnhead;
67static char *addmask_key;
68static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1};
69static char *rn_zeros, *rn_ones;
70
71#define rn_masktop (mask_rnhead->rnh_treetop)
72#undef Bcmp
73#define Bcmp(a, b, l) \
74 (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l))
75
76static int rn_lexobetter __P((void *m_arg, void *n_arg));
77static struct radix_mask *
78 rn_new_radix_mask __P((struct radix_node *tt,
79 struct radix_mask *next));
80static int rn_satsifies_leaf __P((char *trial, struct radix_node *leaf,
81 int skip));
82
83/*
84 * The data structure for the keys is a radix tree with one way
85 * branching removed. The index rn_bit at an internal node n represents a bit
86 * position to be tested. The tree is arranged so that all descendants
87 * of a node n have keys whose bits all agree up to position rn_bit - 1.
88 * (We say the index of n is rn_bit.)
89 *
90 * There is at least one descendant which has a one bit at position rn_bit,
91 * and at least one with a zero there.
92 *
93 * A route is determined by a pair of key and mask. We require that the
94 * bit-wise logical and of the key and mask to be the key.
95 * We define the index of a route to associated with the mask to be
96 * the first bit number in the mask where 0 occurs (with bit number 0
97 * representing the highest order bit).
98 *
99 * We say a mask is normal if every bit is 0, past the index of the mask.
100 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit,
101 * and m is a normal mask, then the route applies to every descendant of n.
102 * If the index(m) < rn_bit, this implies the trailing last few bits of k
103 * before bit b are all 0, (and hence consequently true of every descendant
104 * of n), so the route applies to all descendants of the node as well.
105 *
106 * Similar logic shows that a non-normal mask m such that
107 * index(m) <= index(n) could potentially apply to many children of n.
108 * Thus, for each non-host route, we attach its mask to a list at an internal
109 * node as high in the tree as we can go.
110 *
111 * The present version of the code makes use of normal routes in short-
112 * circuiting an explict mask and compare operation when testing whether
113 * a key satisfies a normal route, and also in remembering the unique leaf
114 * that governs a subtree.
115 */
116
117static struct radix_node *
118rn_search(v_arg, head)
119 void *v_arg;
120 struct radix_node *head;
121{
122 register struct radix_node *x;
123 register caddr_t v;
124
125 for (x = head, v = v_arg; x->rn_bit >= 0;) {
126 if (x->rn_bmask & v[x->rn_offset])
127 x = x->rn_right;
128 else
129 x = x->rn_left;
130 }
131 return (x);
132}
133
134static struct radix_node *
135rn_search_m(v_arg, head, m_arg)
136 struct radix_node *head;
137 void *v_arg, *m_arg;
138{
139 register struct radix_node *x;
140 register caddr_t v = v_arg, m = m_arg;
141
142 for (x = head; x->rn_bit >= 0;) {
143 if ((x->rn_bmask & m[x->rn_offset]) &&
144 (x->rn_bmask & v[x->rn_offset]))
145 x = x->rn_right;
146 else
147 x = x->rn_left;
148 }
149 return x;
150}
151
152int
153rn_refines(m_arg, n_arg)
154 void *m_arg, *n_arg;
155{
156 register caddr_t m = m_arg, n = n_arg;
157 register caddr_t lim, lim2 = lim = n + *(u_char *)n;
158 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++);
159 int masks_are_equal = 1;
160
161 if (longer > 0)
162 lim -= longer;
163 while (n < lim) {
164 if (*n & ~(*m))
165 return 0;
166 if (*n++ != *m++)
167 masks_are_equal = 0;
168 }
169 while (n < lim2)
170 if (*n++)
171 return 0;
172 if (masks_are_equal && (longer < 0))
173 for (lim2 = m - longer; m < lim2; )
174 if (*m++)
175 return 1;
176 return (!masks_are_equal);
177}
178
179struct radix_node *
180rn_lookup(v_arg, m_arg, head)
181 void *v_arg, *m_arg;
182 struct radix_node_head *head;
183{
184 register struct radix_node *x;
185 caddr_t netmask = 0;
186
187 if (m_arg) {
188 x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_offset);
189 if (x == 0)
190 return (0);
191 netmask = x->rn_key;
192 }
193 x = rn_match(v_arg, head);
194 if (x && netmask) {
195 while (x && x->rn_mask != netmask)
196 x = x->rn_dupedkey;
197 }
198 return x;
199}
200
201static int
202rn_satsifies_leaf(trial, leaf, skip)
203 char *trial;
204 register struct radix_node *leaf;
205 int skip;
206{
207 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
208 char *cplim;
209 int length = min(*(u_char *)cp, *(u_char *)cp2);
210
211 if (cp3 == 0)
212 cp3 = rn_ones;
213 else
214 length = min(length, *(u_char *)cp3);
215 cplim = cp + length; cp3 += skip; cp2 += skip;
216 for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
217 if ((*cp ^ *cp2) & *cp3)
218 return 0;
219 return 1;
220}
221
222struct radix_node *
223rn_match(v_arg, head)
224 void *v_arg;
225 struct radix_node_head *head;
226{
227 caddr_t v = v_arg;
228 register struct radix_node *t = head->rnh_treetop, *x;
229 register caddr_t cp = v, cp2;
230 caddr_t cplim;
231 struct radix_node *saved_t, *top = t;
232 int off = t->rn_offset, vlen = *(u_char *)cp, matched_off;
233 register int test, b, rn_bit;
234
235 /*
236 * Open code rn_search(v, top) to avoid overhead of extra
237 * subroutine call.
238 */
239 for (; t->rn_bit >= 0; ) {
240 if (t->rn_bmask & cp[t->rn_offset])
241 t = t->rn_right;
242 else
243 t = t->rn_left;
244 }
245 /*
246 * See if we match exactly as a host destination
247 * or at least learn how many bits match, for normal mask finesse.
248 *
249 * It doesn't hurt us to limit how many bytes to check
250 * to the length of the mask, since if it matches we had a genuine
251 * match and the leaf we have is the most specific one anyway;
252 * if it didn't match with a shorter length it would fail
253 * with a long one. This wins big for class B&C netmasks which
254 * are probably the most common case...
255 */
256 if (t->rn_mask)
257 vlen = *(u_char *)t->rn_mask;
258 cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
259 for (; cp < cplim; cp++, cp2++)
260 if (*cp != *cp2)
261 goto on1;
262 /*
263 * This extra grot is in case we are explicitly asked
264 * to look up the default. Ugh!
265 *
266 * Never return the root node itself, it seems to cause a
267 * lot of confusion.
268 */
269 if (t->rn_flags & RNF_ROOT)
270 t = t->rn_dupedkey;
271 return t;
272on1:
273 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
274 for (b = 7; (test >>= 1) > 0;)
275 b--;
276 matched_off = cp - v;
277 b += matched_off << 3;
278 rn_bit = -1 - b;
279 /*
280 * If there is a host route in a duped-key chain, it will be first.
281 */
282 if ((saved_t = t)->rn_mask == 0)
283 t = t->rn_dupedkey;
284 for (; t; t = t->rn_dupedkey)
285 /*
286 * Even if we don't match exactly as a host,
287 * we may match if the leaf we wound up at is
288 * a route to a net.
289 */
290 if (t->rn_flags & RNF_NORMAL) {
291 if (rn_bit <= t->rn_bit)
292 return t;
293 } else if (rn_satsifies_leaf(v, t, matched_off))
294 return t;
295 t = saved_t;
296 /* start searching up the tree */
297 do {
298 register struct radix_mask *m;
299 t = t->rn_parent;
300 m = t->rn_mklist;
301 /*
302 * If non-contiguous masks ever become important
303 * we can restore the masking and open coding of
304 * the search and satisfaction test and put the
305 * calculation of "off" back before the "do".
306 */
307 while (m) {
308 if (m->rm_flags & RNF_NORMAL) {
309 if (rn_bit <= m->rm_bit)
310 return (m->rm_leaf);
311 } else {
312 off = min(t->rn_offset, matched_off);
313 x = rn_search_m(v, t, m->rm_mask);
314 while (x && x->rn_mask != m->rm_mask)
315 x = x->rn_dupedkey;
316 if (x && rn_satsifies_leaf(v, x, off))
317 return x;
318 }
319 m = m->rm_mklist;
320 }
321 } while (t != top);
322 return 0;
323}
324
325#ifdef RN_DEBUG
326int rn_nodenum;
327struct radix_node *rn_clist;
328int rn_saveinfo;
329int rn_debug = 1;
330#endif
331
332static struct radix_node *
333rn_newpair(v, b, nodes)
334 void *v;
335 int b;
336 struct radix_node nodes[2];
337{
338 register struct radix_node *tt = nodes, *t = tt + 1;
339 t->rn_bit = b;
340 t->rn_bmask = 0x80 >> (b & 7);
341 t->rn_left = tt;
342 t->rn_offset = b >> 3;
343 tt->rn_bit = -1;
344 tt->rn_key = (caddr_t)v;
345 tt->rn_parent = t;
346 tt->rn_flags = t->rn_flags = RNF_ACTIVE;
347 tt->rn_mklist = t->rn_mklist = 0;
348#ifdef RN_DEBUG
349 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
350 tt->rn_twin = t;
351 tt->rn_ybro = rn_clist;
352 rn_clist = tt;
353#endif
354 return t;
355}
356
357static struct radix_node *
358rn_insert(v_arg, head, dupentry, nodes)
359 void *v_arg;
360 struct radix_node_head *head;
361 int *dupentry;
362 struct radix_node nodes[2];
363{
364 caddr_t v = v_arg;
365 struct radix_node *top = head->rnh_treetop;
366 int head_off = top->rn_offset, vlen = (int)*((u_char *)v);
367 register struct radix_node *t = rn_search(v_arg, top);
368 register caddr_t cp = v + head_off;
369 register int b;
370 struct radix_node *tt;
371 /*
372 * Find first bit at which v and t->rn_key differ
373 */
374 {
375 register caddr_t cp2 = t->rn_key + head_off;
376 register int cmp_res;
377 caddr_t cplim = v + vlen;
378
379 while (cp < cplim)
380 if (*cp2++ != *cp++)
381 goto on1;
382 *dupentry = 1;
383 return t;
384on1:
385 *dupentry = 0;
386 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
387 for (b = (cp - v) << 3; cmp_res; b--)
388 cmp_res >>= 1;
389 }
390 {
391 register struct radix_node *p, *x = top;
392 cp = v;
393 do {
394 p = x;
395 if (cp[x->rn_offset] & x->rn_bmask)
396 x = x->rn_right;
397 else
398 x = x->rn_left;
399 } while (b > (unsigned) x->rn_bit);
400 /* x->rn_bit < b && x->rn_bit >= 0 */
401#ifdef RN_DEBUG
402 if (rn_debug)
403 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
404#endif
405 t = rn_newpair(v_arg, b, nodes);
406 tt = t->rn_left;
407 if ((cp[p->rn_offset] & p->rn_bmask) == 0)
408 p->rn_left = t;
409 else
410 p->rn_right = t;
411 x->rn_parent = t;
412 t->rn_parent = p; /* frees x, p as temp vars below */
413 if ((cp[t->rn_offset] & t->rn_bmask) == 0) {
414 t->rn_right = x;
415 } else {
416 t->rn_right = tt;
417 t->rn_left = x;
418 }
419#ifdef RN_DEBUG
420 if (rn_debug)
421 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
422#endif
423 }
424 return (tt);
425}
426
427struct radix_node *
428rn_addmask(n_arg, search, skip)
429 int search, skip;
430 void *n_arg;
431{
432 caddr_t netmask = (caddr_t)n_arg;
433 register struct radix_node *x;
434 register caddr_t cp, cplim;
435 register int b = 0, mlen, j;
436 int maskduplicated, m0, isnormal;
437 struct radix_node *saved_x;
438 static int last_zeroed = 0;
439
440 if ((mlen = *(u_char *)netmask) > max_keylen)
441 mlen = max_keylen;
442 if (skip == 0)
443 skip = 1;
444 if (mlen <= skip)
445 return (mask_rnhead->rnh_nodes);
446 if (skip > 1)
447 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
448 if ((m0 = mlen) > skip)
449 Bcopy(netmask + skip, addmask_key + skip, mlen - skip);
450 /*
451 * Trim trailing zeroes.
452 */
453 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
454 cp--;
455 mlen = cp - addmask_key;
456 if (mlen <= skip) {
457 if (m0 >= last_zeroed)
458 last_zeroed = mlen;
459 return (mask_rnhead->rnh_nodes);
460 }
461 if (m0 < last_zeroed)
462 Bzero(addmask_key + m0, last_zeroed - m0);
463 *addmask_key = last_zeroed = mlen;
464 x = rn_search(addmask_key, rn_masktop);
465 if (Bcmp(addmask_key, x->rn_key, mlen) != 0)
466 x = 0;
467 if (x || search)
468 return (x);
469 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x));
470 if ((saved_x = x) == 0)
471 return (0);
472 Bzero(x, max_keylen + 2 * sizeof (*x));
473 netmask = cp = (caddr_t)(x + 2);
474 Bcopy(addmask_key, cp, mlen);
475 x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
476 if (maskduplicated) {
477 log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
478 Free(saved_x);
479 return (x);
480 }
481 /*
482 * Calculate index of mask, and check for normalcy.
483 */
484 cplim = netmask + mlen; isnormal = 1;
485 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;)
486 cp++;
487 if (cp != cplim) {
488 for (j = 0x80; (j & *cp) != 0; j >>= 1)
489 b++;
490 if (*cp != normal_chars[b] || cp != (cplim - 1))
491 isnormal = 0;
492 }
493 b += (cp - netmask) << 3;
494 x->rn_bit = -1 - b;
495 if (isnormal)
496 x->rn_flags |= RNF_NORMAL;
497 return (x);
498}
499
500static int /* XXX: arbitrary ordering for non-contiguous masks */
501rn_lexobetter(m_arg, n_arg)
502 void *m_arg, *n_arg;
503{
504 register u_char *mp = m_arg, *np = n_arg, *lim;
505
506 if (*mp > *np)
507 return 1; /* not really, but need to check longer one first */
508 if (*mp == *np)
509 for (lim = mp + *mp; mp < lim;)
510 if (*mp++ > *np++)
511 return 1;
512 return 0;
513}
514
515static struct radix_mask *
516rn_new_radix_mask(tt, next)
517 register struct radix_node *tt;
518 register struct radix_mask *next;
519{
520 register struct radix_mask *m;
521
522 MKGet(m);
523 if (m == 0) {
524 log(LOG_ERR, "Mask for route not entered\n");
525 return (0);
526 }
527 Bzero(m, sizeof *m);
528 m->rm_bit = tt->rn_bit;
529 m->rm_flags = tt->rn_flags;
530 if (tt->rn_flags & RNF_NORMAL)
531 m->rm_leaf = tt;
532 else
533 m->rm_mask = tt->rn_mask;
534 m->rm_mklist = next;
535 tt->rn_mklist = m;
536 return m;
537}
538
539struct radix_node *
540rn_addroute(v_arg, n_arg, head, treenodes)
541 void *v_arg, *n_arg;
542 struct radix_node_head *head;
543 struct radix_node treenodes[2];
544{
545 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg;
546 register struct radix_node *t, *x = 0, *tt;
547 struct radix_node *saved_tt, *top = head->rnh_treetop;
548 short b = 0, b_leaf = 0;
549 int keyduplicated;
550 caddr_t mmask;
551 struct radix_mask *m, **mp;
552
553 /*
554 * In dealing with non-contiguous masks, there may be
555 * many different routes which have the same mask.
556 * We will find it useful to have a unique pointer to
557 * the mask to speed avoiding duplicate references at
558 * nodes and possibly save time in calculating indices.
559 */
560 if (netmask) {
561 if ((x = rn_addmask(netmask, 0, top->rn_offset)) == 0)
562 return (0);
563 b_leaf = x->rn_bit;
564 b = -1 - x->rn_bit;
565 netmask = x->rn_key;
566 }
567 /*
568 * Deal with duplicated keys: attach node to previous instance
569 */
570 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes);
571 if (keyduplicated) {
572 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
573 if (tt->rn_mask == netmask)
574 return (0);
575 if (netmask == 0 ||
576 (tt->rn_mask &&
577 ((b_leaf < tt->rn_bit) /* index(netmask) > node */
578 || rn_refines(netmask, tt->rn_mask)
579 || rn_lexobetter(netmask, tt->rn_mask))))
580 break;
581 }
582 /*
583 * If the mask is not duplicated, we wouldn't
584 * find it among possible duplicate key entries
585 * anyway, so the above test doesn't hurt.
586 *
587 * We sort the masks for a duplicated key the same way as
588 * in a masklist -- most specific to least specific.
589 * This may require the unfortunate nuisance of relocating
590 * the head of the list.
591 */
592 if (tt == saved_tt) {
593 struct radix_node *xx = x;
594 /* link in at head of list */
595 (tt = treenodes)->rn_dupedkey = t;
596 tt->rn_flags = t->rn_flags;
597 tt->rn_parent = x = t->rn_parent;
598 t->rn_parent = tt; /* parent */
599 if (x->rn_left == t)
600 x->rn_left = tt;
601 else
602 x->rn_right = tt;
603 saved_tt = tt; x = xx;
604 } else {
605 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
606 t->rn_dupedkey = tt;
607 tt->rn_parent = t; /* parent */
608 if (tt->rn_dupedkey) /* parent */
609 tt->rn_dupedkey->rn_parent = tt; /* parent */
610 }
611#ifdef RN_DEBUG
612 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
613 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
614#endif
615 tt->rn_key = (caddr_t) v;
616 tt->rn_bit = -1;
617 tt->rn_flags = RNF_ACTIVE;
618 }
619 /*
620 * Put mask in tree.
621 */
622 if (netmask) {
623 tt->rn_mask = netmask;
624 tt->rn_bit = x->rn_bit;
625 tt->rn_flags |= x->rn_flags & RNF_NORMAL;
626 }
627 t = saved_tt->rn_parent;
628 if (keyduplicated)
629 goto on2;
630 b_leaf = -1 - t->rn_bit;
631 if (t->rn_right == saved_tt)
632 x = t->rn_left;
633 else
634 x = t->rn_right;
635 /* Promote general routes from below */
636 if (x->rn_bit < 0) {
637 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
638 if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) {
639 *mp = m = rn_new_radix_mask(x, 0);
640 if (m)
641 mp = &m->rm_mklist;
642 }
643 } else if (x->rn_mklist) {
644 /*
645 * Skip over masks whose index is > that of new node
646 */
647 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
648 if (m->rm_bit >= b_leaf)
649 break;
650 t->rn_mklist = m; *mp = 0;
651 }
652on2:
653 /* Add new route to highest possible ancestor's list */
654 if ((netmask == 0) || (b > t->rn_bit ))
655 return tt; /* can't lift at all */
656 b_leaf = tt->rn_bit;
657 do {
658 x = t;
659 t = t->rn_parent;
660 } while (b <= t->rn_bit && x != top);
661 /*
662 * Search through routes associated with node to
663 * insert new route according to index.
664 * Need same criteria as when sorting dupedkeys to avoid
665 * double loop on deletion.
666 */
667 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
668 if (m->rm_bit < b_leaf)
669 continue;
670 if (m->rm_bit > b_leaf)
671 break;
672 if (m->rm_flags & RNF_NORMAL) {
673 mmask = m->rm_leaf->rn_mask;
674 if (tt->rn_flags & RNF_NORMAL) {
675 log(LOG_ERR,
676 "Non-unique normal route, mask not entered\n");
677 return tt;
678 }
679 } else
680 mmask = m->rm_mask;
681 if (mmask == netmask) {
682 m->rm_refs++;
683 tt->rn_mklist = m;
684 return tt;
685 }
686 if (rn_refines(netmask, mmask)
687 || rn_lexobetter(netmask, mmask))
688 break;
689 }
690 *mp = rn_new_radix_mask(tt, *mp);
691 return tt;
692}
693
694struct radix_node *
695rn_delete(v_arg, netmask_arg, head)
696 void *v_arg, *netmask_arg;
697 struct radix_node_head *head;
698{
699 register struct radix_node *t, *p, *x, *tt;
700 struct radix_mask *m, *saved_m, **mp;
701 struct radix_node *dupedkey, *saved_tt, *top;
702 caddr_t v, netmask;
703 int b, head_off, vlen;
704
705 v = v_arg;
706 netmask = netmask_arg;
707 x = head->rnh_treetop;
708 tt = rn_search(v, x);
709 head_off = x->rn_offset;
710 vlen = *(u_char *)v;
711 saved_tt = tt;
712 top = x;
713 if (tt == 0 ||
714 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
715 return (0);
716 /*
717 * Delete our route from mask lists.
718 */
719 if (netmask) {
720 if ((x = rn_addmask(netmask, 1, head_off)) == 0)
721 return (0);
722 netmask = x->rn_key;
723 while (tt->rn_mask != netmask)
724 if ((tt = tt->rn_dupedkey) == 0)
725 return (0);
726 }
727 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0)
728 goto on1;
729 if (tt->rn_flags & RNF_NORMAL) {
730 if (m->rm_leaf != tt || m->rm_refs > 0) {
731 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
732 return 0; /* dangling ref could cause disaster */
733 }
734 } else {
735 if (m->rm_mask != tt->rn_mask) {
736 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
737 goto on1;
738 }
739 if (--m->rm_refs >= 0)
740 goto on1;
741 }
742 b = -1 - tt->rn_bit;
743 t = saved_tt->rn_parent;
744 if (b > t->rn_bit)
745 goto on1; /* Wasn't lifted at all */
746 do {
747 x = t;
748 t = t->rn_parent;
749 } while (b <= t->rn_bit && x != top);
750 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
751 if (m == saved_m) {
752 *mp = m->rm_mklist;
753 MKFree(m);
754 break;
755 }
756 if (m == 0) {
757 log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
758 if (tt->rn_flags & RNF_NORMAL)
759 return (0); /* Dangling ref to us */
760 }
761on1:
762 /*
763 * Eliminate us from tree
764 */
765 if (tt->rn_flags & RNF_ROOT)
766 return (0);
767#ifdef RN_DEBUG
768 /* Get us out of the creation list */
769 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
770 if (t) t->rn_ybro = tt->rn_ybro;
771#endif
772 t = tt->rn_parent;
773 dupedkey = saved_tt->rn_dupedkey;
774 if (dupedkey) {
775 /*
776 * at this point, tt is the deletion target and saved_tt
777 * is the head of the dupekey chain
778 */
779 if (tt == saved_tt) {
780 /* remove from head of chain */
781 x = dupedkey; x->rn_parent = t;
782 if (t->rn_left == tt)
783 t->rn_left = x;
784 else
785 t->rn_right = x;
786 } else {
787 /* find node in front of tt on the chain */
788 for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
789 p = p->rn_dupedkey;
790 if (p) {
791 p->rn_dupedkey = tt->rn_dupedkey;
792 if (tt->rn_dupedkey) /* parent */
793 tt->rn_dupedkey->rn_parent = p;
794 /* parent */
795 } else log(LOG_ERR, "rn_delete: couldn't find us\n");
796 }
797 t = tt + 1;
798 if (t->rn_flags & RNF_ACTIVE) {
799#ifndef RN_DEBUG
800 *++x = *t;
801 p = t->rn_parent;
802#else
803 b = t->rn_info;
804 *++x = *t;
805 t->rn_info = b;
806 p = t->rn_parent;
807#endif
808 if (p->rn_left == t)
809 p->rn_left = x;
810 else
811 p->rn_right = x;
812 x->rn_left->rn_parent = x;
813 x->rn_right->rn_parent = x;
814 }
815 goto out;
816 }
817 if (t->rn_left == tt)
818 x = t->rn_right;
819 else
820 x = t->rn_left;
821 p = t->rn_parent;
822 if (p->rn_right == t)
823 p->rn_right = x;
824 else
825 p->rn_left = x;
826 x->rn_parent = p;
827 /*
828 * Demote routes attached to us.
829 */
830 if (t->rn_mklist) {
831 if (x->rn_bit >= 0) {
832 for (mp = &x->rn_mklist; (m = *mp);)
833 mp = &m->rm_mklist;
834 *mp = t->rn_mklist;
835 } else {
836 /* If there are any key,mask pairs in a sibling
837 duped-key chain, some subset will appear sorted
838 in the same order attached to our mklist */
839 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
840 if (m == x->rn_mklist) {
841 struct radix_mask *mm = m->rm_mklist;
842 x->rn_mklist = 0;
843 if (--(m->rm_refs) < 0)
844 MKFree(m);
845 m = mm;
846 }
847 if (m)
848 log(LOG_ERR,
849 "rn_delete: Orphaned Mask %p at %p\n",
850 (void *)m, (void *)x);
851 }
852 }
853 /*
854 * We may be holding an active internal node in the tree.
855 */
856 x = tt + 1;
857 if (t != x) {
858#ifndef RN_DEBUG
859 *t = *x;
860#else
861 b = t->rn_info;
862 *t = *x;
863 t->rn_info = b;
864#endif
865 t->rn_left->rn_parent = t;
866 t->rn_right->rn_parent = t;
867 p = x->rn_parent;
868 if (p->rn_left == x)
869 p->rn_left = t;
870 else
871 p->rn_right = t;
872 }
873out:
874 tt->rn_flags &= ~RNF_ACTIVE;
875 tt[1].rn_flags &= ~RNF_ACTIVE;
876 return (tt);
877}
878
879/*
880 * This is the same as rn_walktree() except for the parameters and the
881 * exit.
882 */
883static int
884rn_walktree_from(h, a, m, f, w)
885 struct radix_node_head *h;
886 void *a, *m;
887 walktree_f_t *f;
888 void *w;
889{
890 int error;
891 struct radix_node *base, *next;
892 u_char *xa = (u_char *)a;
893 u_char *xm = (u_char *)m;
894 register struct radix_node *rn, *last = 0 /* shut up gcc */;
895 int stopping = 0;
896 int lastb;
897
898 /*
899 * rn_search_m is sort-of-open-coded here.
900 */
901 /* printf("about to search\n"); */
902 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) {
903 last = rn;
904 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n",
905 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */
906 if (!(rn->rn_bmask & xm[rn->rn_offset])) {
907 break;
908 }
909 if (rn->rn_bmask & xa[rn->rn_offset]) {
910 rn = rn->rn_right;
911 } else {
912 rn = rn->rn_left;
913 }
914 }
915 /* printf("done searching\n"); */
916
917 /*
918 * Two cases: either we stepped off the end of our mask,
919 * in which case last == rn, or we reached a leaf, in which
920 * case we want to start from the last node we looked at.
921 * Either way, last is the node we want to start from.
922 */
923 rn = last;
924 lastb = rn->rn_bit;
925
926 /* printf("rn %p, lastb %d\n", rn, lastb);*/
927
928 /*
929 * This gets complicated because we may delete the node
930 * while applying the function f to it, so we need to calculate
931 * the successor node in advance.
932 */
933 while (rn->rn_bit >= 0)
934 rn = rn->rn_left;
935
936 while (!stopping) {
937 /* printf("node %p (%d)\n", rn, rn->rn_bit); */
938 base = rn;
939 /* If at right child go back up, otherwise, go right */
940 while (rn->rn_parent->rn_right == rn
941 && !(rn->rn_flags & RNF_ROOT)) {
942 rn = rn->rn_parent;
943
944 /* if went up beyond last, stop */
945 if (rn->rn_bit < lastb) {
946 stopping = 1;
947 /* printf("up too far\n"); */
948 }
949 }
950
951 /* Find the next *leaf* since next node might vanish, too */
952 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
953 rn = rn->rn_left;
954 next = rn;
955 /* Process leaves */
956 while ((rn = base) != 0) {
957 base = rn->rn_dupedkey;
958 /* printf("leaf %p\n", rn); */
959 if (!(rn->rn_flags & RNF_ROOT)
960 && (error = (*f)(rn, w)))
961 return (error);
962 }
963 rn = next;
964
965 if (rn->rn_flags & RNF_ROOT) {
966 /* printf("root, stopping"); */
967 stopping = 1;
968 }
969
970 }
971 return 0;
972}
973
974static int
975rn_walktree(h, f, w)
976 struct radix_node_head *h;
977 walktree_f_t *f;
978 void *w;
979{
980 int error;
981 struct radix_node *base, *next;
982 register struct radix_node *rn = h->rnh_treetop;
983 /*
984 * This gets complicated because we may delete the node
985 * while applying the function f to it, so we need to calculate
986 * the successor node in advance.
987 */
988 /* First time through node, go left */
989 while (rn->rn_bit >= 0)
990 rn = rn->rn_left;
991 for (;;) {
992 base = rn;
993 /* If at right child go back up, otherwise, go right */
994 while (rn->rn_parent->rn_right == rn
995 && (rn->rn_flags & RNF_ROOT) == 0)
996 rn = rn->rn_parent;
997 /* Find the next *leaf* since next node might vanish, too */
998 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
999 rn = rn->rn_left;
1000 next = rn;
1001 /* Process leaves */
1002 while ((rn = base)) {
1003 base = rn->rn_dupedkey;
1004 if (!(rn->rn_flags & RNF_ROOT)
1005 && (error = (*f)(rn, w)))
1006 return (error);
1007 }
1008 rn = next;
1009 if (rn->rn_flags & RNF_ROOT)
1010 return (0);
1011 }
1012 /* NOTREACHED */
1013}
1014
1015int
1016rn_inithead(head, off)
1017 void **head;
1018 int off;
1019{
1020 register struct radix_node_head *rnh;
1021 register struct radix_node *t, *tt, *ttt;
1022 if (*head)
1023 return (1);
1024 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh));
1025 if (rnh == 0)
1026 return (0);
1027 Bzero(rnh, sizeof (*rnh));
1028 *head = rnh;
1029 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
1030 ttt = rnh->rnh_nodes + 2;
1031 t->rn_right = ttt;
1032 t->rn_parent = t;
1033 tt = t->rn_left;
1034 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
1035 tt->rn_bit = -1 - off;
1036 *ttt = *tt;
1037 ttt->rn_key = rn_ones;
1038 rnh->rnh_addaddr = rn_addroute;
1039 rnh->rnh_deladdr = rn_delete;
1040 rnh->rnh_matchaddr = rn_match;
1041 rnh->rnh_lookup = rn_lookup;
1042 rnh->rnh_walktree = rn_walktree;
1043 rnh->rnh_walktree_from = rn_walktree_from;
1044 rnh->rnh_treetop = t;
1045 return (1);
1046}
1047
1048void
1049rn_init()
1050{
1051 char *cp, *cplim;
1052#ifdef _KERNEL
1053 struct domain *dom;
1054
1055 for (dom = domains; dom; dom = dom->dom_next)
1056 if (dom->dom_maxrtkey > max_keylen)
1057 max_keylen = dom->dom_maxrtkey;
1058#endif
1059 if (max_keylen == 0) {
1060 log(LOG_ERR,
1061 "rn_init: radix functions require max_keylen be set\n");
1062 return;
1063 }
1064 R_Malloc(rn_zeros, char *, 3 * max_keylen);
1065 if (rn_zeros == NULL)
1066 panic("rn_init");
1067 Bzero(rn_zeros, 3 * max_keylen);
1068 rn_ones = cp = rn_zeros + max_keylen;
1069 addmask_key = cplim = rn_ones + max_keylen;
1070 while (cp < cplim)
1071 *cp++ = -1;
1072 if (rn_inithead((void **)&mask_rnhead, 0) == 0)
1073 panic("rn_init 2");
1074}