Merge branch 'master' of ssh://crater.dragonflybsd.org/repository/git/dragonfly
[dragonfly.git] / sys / net / radix.c
blobb84ce77e18ca6dea2462a35b179b4c6d0c5b4b40
1 /*
2 * Copyright (c) 1988, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
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.
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.
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 * $DragonFly: src/sys/net/radix.c,v 1.14 2006/12/22 23:44:54 swildner Exp $
39 * Routines to build and maintain radix trees for routing lookups.
41 #include <sys/param.h>
42 #ifdef _KERNEL
43 #include <sys/systm.h>
44 #include <sys/malloc.h>
45 #include <sys/domain.h>
46 #else
47 #include <stdlib.h>
48 #endif
49 #include <sys/syslog.h>
50 #include <net/radix.h>
53 * The arguments to the radix functions are really counted byte arrays with
54 * the length in the first byte. struct sockaddr's fit this type structurally.
56 #define clen(c) (*(u_char *)(c))
58 static int rn_walktree_from(struct radix_node_head *h, char *a, char *m,
59 walktree_f_t *f, void *w);
60 static int rn_walktree(struct radix_node_head *, walktree_f_t *, void *);
62 static struct radix_node
63 *rn_insert(char *, struct radix_node_head *, boolean_t *,
64 struct radix_node [2]),
65 *rn_newpair(char *, int, struct radix_node[2]),
66 *rn_search(const char *, struct radix_node *),
67 *rn_search_m(const char *, struct radix_node *, const char *);
69 static struct radix_mask *rn_mkfreelist;
70 static struct radix_node_head *mask_rnhead;
72 static int max_keylen;
73 static char *rn_zeros, *rn_ones;
75 static int rn_lexobetter(char *m, char *n);
76 static struct radix_mask *
77 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *nextmask);
78 static boolean_t
79 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip);
81 static __inline struct radix_mask *
82 MKGet(struct radix_mask **l)
84 struct radix_mask *m;
86 if (*l != NULL) {
87 m = *l;
88 *l = m->rm_next;
89 } else {
90 R_Malloc(m, struct radix_mask *, sizeof *m);
92 return m;
95 static __inline void
96 MKFree(struct radix_mask **l, struct radix_mask *m)
98 m->rm_next = *l;
99 *l = m;
103 * The data structure for the keys is a radix tree with one way
104 * branching removed. The index rn_bit at an internal node n represents a bit
105 * position to be tested. The tree is arranged so that all descendants
106 * of a node n have keys whose bits all agree up to position rn_bit - 1.
107 * (We say the index of n is rn_bit.)
109 * There is at least one descendant which has a one bit at position rn_bit,
110 * and at least one with a zero there.
112 * A route is determined by a pair of key and mask. We require that the
113 * bit-wise logical and of the key and mask to be the key.
114 * We define the index of a route to associated with the mask to be
115 * the first bit number in the mask where 0 occurs (with bit number 0
116 * representing the highest order bit).
118 * We say a mask is normal if every bit is 0, past the index of the mask.
119 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit,
120 * and m is a normal mask, then the route applies to every descendant of n.
121 * If the index(m) < rn_bit, this implies the trailing last few bits of k
122 * before bit b are all 0, (and hence consequently true of every descendant
123 * of n), so the route applies to all descendants of the node as well.
125 * Similar logic shows that a non-normal mask m such that
126 * index(m) <= index(n) could potentially apply to many children of n.
127 * Thus, for each non-host route, we attach its mask to a list at an internal
128 * node as high in the tree as we can go.
130 * The present version of the code makes use of normal routes in short-
131 * circuiting an explict mask and compare operation when testing whether
132 * a key satisfies a normal route, and also in remembering the unique leaf
133 * that governs a subtree.
136 static struct radix_node *
137 rn_search(const char *v, struct radix_node *head)
139 struct radix_node *x;
141 x = head;
142 while (x->rn_bit >= 0) {
143 if (x->rn_bmask & v[x->rn_offset])
144 x = x->rn_right;
145 else
146 x = x->rn_left;
148 return (x);
151 static struct radix_node *
152 rn_search_m(const char *v, struct radix_node *head, const char *m)
154 struct radix_node *x;
156 for (x = head; x->rn_bit >= 0;) {
157 if ((x->rn_bmask & m[x->rn_offset]) &&
158 (x->rn_bmask & v[x->rn_offset]))
159 x = x->rn_right;
160 else
161 x = x->rn_left;
163 return x;
166 boolean_t
167 rn_refines(char *m, char *n)
169 char *lim, *lim2;
170 int longer = clen(n++) - clen(m++);
171 boolean_t masks_are_equal = TRUE;
173 lim2 = lim = n + clen(n);
174 if (longer > 0)
175 lim -= longer;
176 while (n < lim) {
177 if (*n & ~(*m))
178 return FALSE;
179 if (*n++ != *m++)
180 masks_are_equal = FALSE;
182 while (n < lim2)
183 if (*n++)
184 return FALSE;
185 if (masks_are_equal && (longer < 0))
186 for (lim2 = m - longer; m < lim2; )
187 if (*m++)
188 return TRUE;
189 return (!masks_are_equal);
192 struct radix_node *
193 rn_lookup(char *key, char *mask, struct radix_node_head *head)
195 struct radix_node *x;
196 char *netmask = NULL;
198 if (mask != NULL) {
199 x = rn_addmask(mask, TRUE, head->rnh_treetop->rn_offset);
200 if (x == NULL)
201 return (NULL);
202 netmask = x->rn_key;
204 x = rn_match(key, head);
205 if (x != NULL && netmask != NULL) {
206 while (x != NULL && x->rn_mask != netmask)
207 x = x->rn_dupedkey;
209 return x;
212 static boolean_t
213 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip)
215 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
216 char *cplim;
217 int length = min(clen(cp), clen(cp2));
219 if (cp3 == NULL)
220 cp3 = rn_ones;
221 else
222 length = min(length, clen(cp3));
223 cplim = cp + length;
224 cp3 += skip;
225 cp2 += skip;
226 for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
227 if ((*cp ^ *cp2) & *cp3)
228 return FALSE;
229 return TRUE;
232 struct radix_node *
233 rn_match(char *key, struct radix_node_head *head)
235 struct radix_node *t, *x;
236 char *cp = key, *cp2;
237 char *cplim;
238 struct radix_node *saved_t, *top = head->rnh_treetop;
239 int off = top->rn_offset, klen, matched_off;
240 int test, b, rn_bit;
242 t = rn_search(key, top);
244 * See if we match exactly as a host destination
245 * or at least learn how many bits match, for normal mask finesse.
247 * It doesn't hurt us to limit how many bytes to check
248 * to the length of the mask, since if it matches we had a genuine
249 * match and the leaf we have is the most specific one anyway;
250 * if it didn't match with a shorter length it would fail
251 * with a long one. This wins big for class B&C netmasks which
252 * are probably the most common case...
254 if (t->rn_mask != NULL)
255 klen = clen(t->rn_mask);
256 else
257 klen = clen(key);
258 cp += off; cp2 = t->rn_key + off; cplim = key + klen;
259 for (; cp < cplim; cp++, cp2++)
260 if (*cp != *cp2)
261 goto on1;
263 * This extra grot is in case we are explicitly asked
264 * to look up the default. Ugh!
266 * Never return the root node itself, it seems to cause a
267 * lot of confusion.
269 if (t->rn_flags & RNF_ROOT)
270 t = t->rn_dupedkey;
271 return t;
272 on1:
273 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
274 for (b = 7; (test >>= 1) > 0;)
275 b--;
276 matched_off = cp - key;
277 b += matched_off << 3;
278 rn_bit = -1 - b;
280 * If there is a host route in a duped-key chain, it will be first.
282 if ((saved_t = t)->rn_mask == NULL)
283 t = t->rn_dupedkey;
284 for (; t; t = t->rn_dupedkey) {
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.
290 if (t->rn_flags & RNF_NORMAL) {
291 if (rn_bit <= t->rn_bit)
292 return t;
293 } else if (rn_satisfies_leaf(key, t, matched_off))
294 return t;
296 t = saved_t;
297 /* start searching up the tree */
298 do {
299 struct radix_mask *m;
301 t = t->rn_parent;
303 * If non-contiguous masks ever become important
304 * we can restore the masking and open coding of
305 * the search and satisfaction test and put the
306 * calculation of "off" back before the "do".
308 m = t->rn_mklist;
309 while (m != NULL) {
310 if (m->rm_flags & RNF_NORMAL) {
311 if (rn_bit <= m->rm_bit)
312 return (m->rm_leaf);
313 } else {
314 off = min(t->rn_offset, matched_off);
315 x = rn_search_m(key, t, m->rm_mask);
316 while (x != NULL && x->rn_mask != m->rm_mask)
317 x = x->rn_dupedkey;
318 if (x && rn_satisfies_leaf(key, x, off))
319 return x;
321 m = m->rm_next;
323 } while (t != top);
324 return NULL;
327 #ifdef RN_DEBUG
328 int rn_nodenum;
329 struct radix_node *rn_clist;
330 int rn_saveinfo;
331 boolean_t rn_debug = TRUE;
332 #endif
334 static struct radix_node *
335 rn_newpair(char *key, int indexbit, struct radix_node nodes[2])
337 struct radix_node *leaf = &nodes[0], *interior = &nodes[1];
339 interior->rn_bit = indexbit;
340 interior->rn_bmask = 0x80 >> (indexbit & 0x7);
341 interior->rn_offset = indexbit >> 3;
342 interior->rn_left = leaf;
343 interior->rn_mklist = NULL;
345 leaf->rn_bit = -1;
346 leaf->rn_key = key;
347 leaf->rn_parent = interior;
348 leaf->rn_flags = interior->rn_flags = RNF_ACTIVE;
349 leaf->rn_mklist = NULL;
351 #ifdef RN_DEBUG
352 leaf->rn_info = rn_nodenum++;
353 interior->rn_info = rn_nodenum++;
354 leaf->rn_twin = interior;
355 leaf->rn_ybro = rn_clist;
356 rn_clist = leaf;
357 #endif
358 return interior;
361 static struct radix_node *
362 rn_insert(char *key, struct radix_node_head *head, boolean_t *dupentry,
363 struct radix_node nodes[2])
365 struct radix_node *top = head->rnh_treetop;
366 int head_off = top->rn_offset, klen = clen(key);
367 struct radix_node *t = rn_search(key, top);
368 char *cp = key + head_off;
369 int b;
370 struct radix_node *tt;
373 * Find first bit at which the key and t->rn_key differ
376 char *cp2 = t->rn_key + head_off;
377 int cmp_res;
378 char *cplim = key + klen;
380 while (cp < cplim)
381 if (*cp2++ != *cp++)
382 goto on1;
383 *dupentry = TRUE;
384 return t;
385 on1:
386 *dupentry = FALSE;
387 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
388 for (b = (cp - key) << 3; cmp_res; b--)
389 cmp_res >>= 1;
392 struct radix_node *p, *x = top;
394 cp = key;
395 do {
396 p = x;
397 if (cp[x->rn_offset] & x->rn_bmask)
398 x = x->rn_right;
399 else
400 x = x->rn_left;
401 } while (b > (unsigned) x->rn_bit);
402 /* x->rn_bit < b && x->rn_bit >= 0 */
403 #ifdef RN_DEBUG
404 if (rn_debug)
405 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
406 #endif
407 t = rn_newpair(key, b, nodes);
408 tt = t->rn_left;
409 if ((cp[p->rn_offset] & p->rn_bmask) == 0)
410 p->rn_left = t;
411 else
412 p->rn_right = t;
413 x->rn_parent = t;
414 t->rn_parent = p; /* frees x, p as temp vars below */
415 if ((cp[t->rn_offset] & t->rn_bmask) == 0) {
416 t->rn_right = x;
417 } else {
418 t->rn_right = tt;
419 t->rn_left = x;
421 #ifdef RN_DEBUG
422 if (rn_debug)
423 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
424 #endif
426 return (tt);
429 struct radix_node *
430 rn_addmask(char *netmask, boolean_t search, int skip)
432 struct radix_node *x, *saved_x;
433 char *cp, *cplim;
434 int b = 0, mlen, m0, j;
435 boolean_t maskduplicated, isnormal;
436 static int last_zeroed = 0;
437 char *addmask_key;
439 if ((mlen = clen(netmask)) > max_keylen)
440 mlen = max_keylen;
441 if (skip == 0)
442 skip = 1;
443 if (mlen <= skip)
444 return (mask_rnhead->rnh_nodes);
445 R_Malloc(addmask_key, char *, max_keylen);
446 if (addmask_key == NULL)
447 return NULL;
448 if (skip > 1)
449 bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
450 if ((m0 = mlen) > skip)
451 bcopy(netmask + skip, addmask_key + skip, mlen - skip);
453 * Trim trailing zeroes.
455 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
456 cp--;
457 mlen = cp - addmask_key;
458 if (mlen <= skip) {
459 if (m0 >= last_zeroed)
460 last_zeroed = mlen;
461 Free(addmask_key);
462 return (mask_rnhead->rnh_nodes);
464 if (m0 < last_zeroed)
465 bzero(addmask_key + m0, last_zeroed - m0);
466 *addmask_key = last_zeroed = mlen;
467 x = rn_search(addmask_key, mask_rnhead->rnh_treetop);
468 if (bcmp(addmask_key, x->rn_key, mlen) != 0)
469 x = NULL;
470 if (x != NULL || search)
471 goto out;
472 R_Malloc(x, struct radix_node *, max_keylen + 2 * (sizeof *x));
473 if ((saved_x = x) == NULL)
474 goto out;
475 bzero(x, max_keylen + 2 * (sizeof *x));
476 netmask = cp = (char *)(x + 2);
477 bcopy(addmask_key, cp, mlen);
478 x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
479 if (maskduplicated) {
480 log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
481 Free(saved_x);
482 goto out;
485 * Calculate index of mask, and check for normalcy.
487 isnormal = TRUE;
488 cplim = netmask + mlen;
489 for (cp = netmask + skip; cp < cplim && clen(cp) == 0xff;)
490 cp++;
491 if (cp != cplim) {
492 static const char normal_chars[] = {
493 0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1
496 for (j = 0x80; (j & *cp) != 0; j >>= 1)
497 b++;
498 if (*cp != normal_chars[b] || cp != (cplim - 1))
499 isnormal = FALSE;
501 b += (cp - netmask) << 3;
502 x->rn_bit = -1 - b;
503 if (isnormal)
504 x->rn_flags |= RNF_NORMAL;
505 out:
506 Free(addmask_key);
507 return (x);
510 /* XXX: arbitrary ordering for non-contiguous masks */
511 static boolean_t
512 rn_lexobetter(char *mp, char *np)
514 char *lim;
516 if ((unsigned) *mp > (unsigned) *np)
517 return TRUE;/* not really, but need to check longer one first */
518 if (*mp == *np)
519 for (lim = mp + clen(mp); mp < lim;)
520 if (*mp++ > *np++)
521 return TRUE;
522 return FALSE;
525 static struct radix_mask *
526 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *nextmask)
528 struct radix_mask *m;
530 m = MKGet(&rn_mkfreelist);
531 if (m == NULL) {
532 log(LOG_ERR, "Mask for route not entered\n");
533 return (NULL);
535 bzero(m, sizeof *m);
536 m->rm_bit = tt->rn_bit;
537 m->rm_flags = tt->rn_flags;
538 if (tt->rn_flags & RNF_NORMAL)
539 m->rm_leaf = tt;
540 else
541 m->rm_mask = tt->rn_mask;
542 m->rm_next = nextmask;
543 tt->rn_mklist = m;
544 return m;
547 struct radix_node *
548 rn_addroute(char *key, char *netmask, struct radix_node_head *head,
549 struct radix_node treenodes[2])
551 struct radix_node *t, *x = NULL, *tt;
552 struct radix_node *saved_tt, *top = head->rnh_treetop;
553 short b = 0, b_leaf = 0;
554 boolean_t keyduplicated;
555 char *mmask;
556 struct radix_mask *m, **mp;
559 * In dealing with non-contiguous masks, there may be
560 * many different routes which have the same mask.
561 * We will find it useful to have a unique pointer to
562 * the mask to speed avoiding duplicate references at
563 * nodes and possibly save time in calculating indices.
565 if (netmask != NULL) {
566 if ((x = rn_addmask(netmask, FALSE, top->rn_offset)) == NULL)
567 return (NULL);
568 b_leaf = x->rn_bit;
569 b = -1 - x->rn_bit;
570 netmask = x->rn_key;
573 * Deal with duplicated keys: attach node to previous instance
575 saved_tt = tt = rn_insert(key, head, &keyduplicated, treenodes);
576 if (keyduplicated) {
577 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
578 if (tt->rn_mask == netmask)
579 return (NULL);
580 if (netmask == NULL ||
581 (tt->rn_mask &&
582 ((b_leaf < tt->rn_bit) /* index(netmask) > node */
583 || rn_refines(netmask, tt->rn_mask)
584 || rn_lexobetter(netmask, tt->rn_mask))))
585 break;
588 * If the mask is not duplicated, we wouldn't
589 * find it among possible duplicate key entries
590 * anyway, so the above test doesn't hurt.
592 * We sort the masks for a duplicated key the same way as
593 * in a masklist -- most specific to least specific.
594 * This may require the unfortunate nuisance of relocating
595 * the head of the list.
597 if (tt == saved_tt) {
598 struct radix_node *xx = x;
599 /* link in at head of list */
600 (tt = treenodes)->rn_dupedkey = t;
601 tt->rn_flags = t->rn_flags;
602 tt->rn_parent = x = t->rn_parent;
603 t->rn_parent = tt; /* parent */
604 if (x->rn_left == t)
605 x->rn_left = tt;
606 else
607 x->rn_right = tt;
608 saved_tt = tt; x = xx;
609 } else {
610 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
611 t->rn_dupedkey = tt;
612 tt->rn_parent = t; /* parent */
613 if (tt->rn_dupedkey != NULL) /* parent */
614 tt->rn_dupedkey->rn_parent = tt; /* parent */
616 #ifdef RN_DEBUG
617 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
618 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
619 #endif
620 tt->rn_key = key;
621 tt->rn_bit = -1;
622 tt->rn_flags = RNF_ACTIVE;
625 * Put mask in tree.
627 if (netmask != NULL) {
628 tt->rn_mask = netmask;
629 tt->rn_bit = x->rn_bit;
630 tt->rn_flags |= x->rn_flags & RNF_NORMAL;
632 t = saved_tt->rn_parent;
633 if (keyduplicated)
634 goto on2;
635 b_leaf = -1 - t->rn_bit;
636 if (t->rn_right == saved_tt)
637 x = t->rn_left;
638 else
639 x = t->rn_right;
640 /* Promote general routes from below */
641 if (x->rn_bit < 0) {
642 mp = &t->rn_mklist;
643 while (x != NULL) {
644 if (x->rn_mask != NULL &&
645 x->rn_bit >= b_leaf &&
646 x->rn_mklist == NULL) {
647 *mp = m = rn_new_radix_mask(x, NULL);
648 if (m != NULL)
649 mp = &m->rm_next;
651 x = x->rn_dupedkey;
653 } else if (x->rn_mklist != NULL) {
655 * Skip over masks whose index is > that of new node
657 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next)
658 if (m->rm_bit >= b_leaf)
659 break;
660 t->rn_mklist = m;
661 *mp = NULL;
663 on2:
664 /* Add new route to highest possible ancestor's list */
665 if ((netmask == NULL) || (b > t->rn_bit ))
666 return tt; /* can't lift at all */
667 b_leaf = tt->rn_bit;
668 do {
669 x = t;
670 t = t->rn_parent;
671 } while (b <= t->rn_bit && x != top);
673 * Search through routes associated with node to
674 * insert new route according to index.
675 * Need same criteria as when sorting dupedkeys to avoid
676 * double loop on deletion.
678 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) {
679 if (m->rm_bit < b_leaf)
680 continue;
681 if (m->rm_bit > b_leaf)
682 break;
683 if (m->rm_flags & RNF_NORMAL) {
684 mmask = m->rm_leaf->rn_mask;
685 if (tt->rn_flags & RNF_NORMAL) {
686 log(LOG_ERR,
687 "Non-unique normal route, mask not entered\n");
688 return tt;
690 } else
691 mmask = m->rm_mask;
692 if (mmask == netmask) {
693 m->rm_refs++;
694 tt->rn_mklist = m;
695 return tt;
697 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask))
698 break;
700 *mp = rn_new_radix_mask(tt, *mp);
701 return tt;
704 struct radix_node *
705 rn_delete(char *key, char *netmask, struct radix_node_head *head)
707 struct radix_node *t, *p, *x, *tt;
708 struct radix_mask *m, *saved_m, **mp;
709 struct radix_node *dupedkey, *saved_tt, *top;
710 int b, head_off, klen;
712 x = head->rnh_treetop;
713 tt = rn_search(key, x);
714 head_off = x->rn_offset;
715 klen = clen(key);
716 saved_tt = tt;
717 top = x;
718 if (tt == NULL ||
719 bcmp(key + head_off, tt->rn_key + head_off, klen - head_off))
720 return (NULL);
722 * Delete our route from mask lists.
724 if (netmask != NULL) {
725 if ((x = rn_addmask(netmask, TRUE, head_off)) == NULL)
726 return (NULL);
727 netmask = x->rn_key;
728 while (tt->rn_mask != netmask)
729 if ((tt = tt->rn_dupedkey) == NULL)
730 return (NULL);
732 if (tt->rn_mask == NULL || (saved_m = m = tt->rn_mklist) == NULL)
733 goto on1;
734 if (tt->rn_flags & RNF_NORMAL) {
735 if (m->rm_leaf != tt || m->rm_refs > 0) {
736 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
737 return (NULL); /* dangling ref could cause disaster */
739 } else {
740 if (m->rm_mask != tt->rn_mask) {
741 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
742 goto on1;
744 if (--m->rm_refs >= 0)
745 goto on1;
747 b = -1 - tt->rn_bit;
748 t = saved_tt->rn_parent;
749 if (b > t->rn_bit)
750 goto on1; /* Wasn't lifted at all */
751 do {
752 x = t;
753 t = t->rn_parent;
754 } while (b <= t->rn_bit && x != top);
755 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next)
756 if (m == saved_m) {
757 *mp = m->rm_next;
758 MKFree(&rn_mkfreelist, m);
759 break;
761 if (m == NULL) {
762 log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
763 if (tt->rn_flags & RNF_NORMAL)
764 return (NULL); /* Dangling ref to us */
766 on1:
768 * Eliminate us from tree
770 if (tt->rn_flags & RNF_ROOT)
771 return (NULL);
772 #ifdef RN_DEBUG
773 /* Get us out of the creation list */
774 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
775 if (t) t->rn_ybro = tt->rn_ybro;
776 #endif
777 t = tt->rn_parent;
778 dupedkey = saved_tt->rn_dupedkey;
779 if (dupedkey != NULL) {
781 * at this point, tt is the deletion target and saved_tt
782 * is the head of the dupekey chain
784 if (tt == saved_tt) {
785 /* remove from head of chain */
786 x = dupedkey; x->rn_parent = t;
787 if (t->rn_left == tt)
788 t->rn_left = x;
789 else
790 t->rn_right = x;
791 } else {
792 /* find node in front of tt on the chain */
793 for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
794 p = p->rn_dupedkey;
795 if (p) {
796 p->rn_dupedkey = tt->rn_dupedkey;
797 if (tt->rn_dupedkey) /* parent */
798 tt->rn_dupedkey->rn_parent = p;
799 /* parent */
800 } else log(LOG_ERR, "rn_delete: couldn't find us\n");
802 t = tt + 1;
803 if (t->rn_flags & RNF_ACTIVE) {
804 #ifndef RN_DEBUG
805 *++x = *t;
806 p = t->rn_parent;
807 #else
808 b = t->rn_info;
809 *++x = *t;
810 t->rn_info = b;
811 p = t->rn_parent;
812 #endif
813 if (p->rn_left == t)
814 p->rn_left = x;
815 else
816 p->rn_right = x;
817 x->rn_left->rn_parent = x;
818 x->rn_right->rn_parent = x;
820 goto out;
822 if (t->rn_left == tt)
823 x = t->rn_right;
824 else
825 x = t->rn_left;
826 p = t->rn_parent;
827 if (p->rn_right == t)
828 p->rn_right = x;
829 else
830 p->rn_left = x;
831 x->rn_parent = p;
833 * Demote routes attached to us.
835 if (t->rn_mklist != NULL) {
836 if (x->rn_bit >= 0) {
837 for (mp = &x->rn_mklist; (m = *mp);)
838 mp = &m->rm_next;
839 *mp = t->rn_mklist;
840 } else {
842 * If there are any (key, mask) pairs in a sibling
843 * duped-key chain, some subset will appear sorted
844 * in the same order attached to our mklist.
846 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
847 if (m == x->rn_mklist) {
848 struct radix_mask *mm = m->rm_next;
850 x->rn_mklist = NULL;
851 if (--(m->rm_refs) < 0)
852 MKFree(&rn_mkfreelist, m);
853 m = mm;
855 if (m)
856 log(LOG_ERR,
857 "rn_delete: Orphaned Mask %p at %p\n",
858 (void *)m, (void *)x);
862 * We may be holding an active internal node in the tree.
864 x = tt + 1;
865 if (t != x) {
866 #ifndef RN_DEBUG
867 *t = *x;
868 #else
869 b = t->rn_info;
870 *t = *x;
871 t->rn_info = b;
872 #endif
873 t->rn_left->rn_parent = t;
874 t->rn_right->rn_parent = t;
875 p = x->rn_parent;
876 if (p->rn_left == x)
877 p->rn_left = t;
878 else
879 p->rn_right = t;
881 out:
882 tt->rn_flags &= ~RNF_ACTIVE;
883 tt[1].rn_flags &= ~RNF_ACTIVE;
884 return (tt);
888 * This is the same as rn_walktree() except for the parameters and the
889 * exit.
891 static int
892 rn_walktree_from(struct radix_node_head *h, char *xa, char *xm,
893 walktree_f_t *f, void *w)
895 struct radix_node *base, *next;
896 struct radix_node *rn, *last = NULL /* shut up gcc */;
897 boolean_t stopping = FALSE;
898 int lastb, error;
901 * rn_search_m is sort-of-open-coded here.
903 /* kprintf("about to search\n"); */
904 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) {
905 last = rn;
906 /* kprintf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n",
907 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */
908 if (!(rn->rn_bmask & xm[rn->rn_offset])) {
909 break;
911 if (rn->rn_bmask & xa[rn->rn_offset]) {
912 rn = rn->rn_right;
913 } else {
914 rn = rn->rn_left;
917 /* kprintf("done searching\n"); */
920 * Two cases: either we stepped off the end of our mask,
921 * in which case last == rn, or we reached a leaf, in which
922 * case we want to start from the last node we looked at.
923 * Either way, last is the node we want to start from.
925 rn = last;
926 lastb = rn->rn_bit;
928 /* kprintf("rn %p, lastb %d\n", rn, lastb);*/
931 * This gets complicated because we may delete the node
932 * while applying the function f to it, so we need to calculate
933 * the successor node in advance.
935 while (rn->rn_bit >= 0)
936 rn = rn->rn_left;
938 while (!stopping) {
939 /* kprintf("node %p (%d)\n", rn, rn->rn_bit); */
940 base = rn;
941 /* If at right child go back up, otherwise, go right */
942 while (rn->rn_parent->rn_right == rn &&
943 !(rn->rn_flags & RNF_ROOT)) {
944 rn = rn->rn_parent;
946 /* if went up beyond last, stop */
947 if (rn->rn_bit < lastb) {
948 stopping = TRUE;
949 /* kprintf("up too far\n"); */
953 /* Find the next *leaf* since next node might vanish, too */
954 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
955 rn = rn->rn_left;
956 next = rn;
957 /* Process leaves */
958 while ((rn = base) != NULL) {
959 base = rn->rn_dupedkey;
960 /* kprintf("leaf %p\n", rn); */
961 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w)))
962 return (error);
964 rn = next;
966 if (rn->rn_flags & RNF_ROOT) {
967 /* kprintf("root, stopping"); */
968 stopping = TRUE;
972 return 0;
975 static int
976 rn_walktree(struct radix_node_head *h, walktree_f_t *f, void *w)
978 struct radix_node *base, *next;
979 struct radix_node *rn = h->rnh_treetop;
980 int error;
983 * This gets complicated because we may delete the node
984 * while applying the function f to it, so we need to calculate
985 * the successor node in advance.
987 /* First time through node, go left */
988 while (rn->rn_bit >= 0)
989 rn = rn->rn_left;
990 for (;;) {
991 base = rn;
992 /* If at right child go back up, otherwise, go right */
993 while (rn->rn_parent->rn_right == rn &&
994 !(rn->rn_flags & RNF_ROOT))
995 rn = rn->rn_parent;
996 /* Find the next *leaf* since next node might vanish, too */
997 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
998 rn = rn->rn_left;
999 next = rn;
1000 /* Process leaves */
1001 while ((rn = base)) {
1002 base = rn->rn_dupedkey;
1003 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w)))
1004 return (error);
1006 rn = next;
1007 if (rn->rn_flags & RNF_ROOT)
1008 return (0);
1010 /* NOTREACHED */
1014 rn_inithead(void **head, int off)
1016 struct radix_node_head *rnh;
1017 struct radix_node *root, *left, *right;
1019 if (*head != NULL) /* already initialized */
1020 return (1);
1022 R_Malloc(rnh, struct radix_node_head *, sizeof *rnh);
1023 if (rnh == NULL)
1024 return (0);
1025 bzero(rnh, sizeof *rnh);
1026 *head = rnh;
1028 root = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
1029 right = &rnh->rnh_nodes[2];
1030 root->rn_parent = root;
1031 root->rn_flags = RNF_ROOT | RNF_ACTIVE;
1032 root->rn_right = right;
1034 left = root->rn_left;
1035 left->rn_bit = -1 - off;
1036 left->rn_flags = RNF_ROOT | RNF_ACTIVE;
1038 *right = *left;
1039 right->rn_key = rn_ones;
1041 rnh->rnh_treetop = root;
1043 rnh->rnh_addaddr = rn_addroute;
1044 rnh->rnh_deladdr = rn_delete;
1045 rnh->rnh_matchaddr = rn_match;
1046 rnh->rnh_lookup = rn_lookup;
1047 rnh->rnh_walktree = rn_walktree;
1048 rnh->rnh_walktree_from = rn_walktree_from;
1050 return (1);
1053 void
1054 rn_init(void)
1056 char *cp, *cplim;
1057 #ifdef _KERNEL
1058 struct domain *dom;
1060 SLIST_FOREACH(dom, &domains, dom_next)
1061 if (dom->dom_maxrtkey > max_keylen)
1062 max_keylen = dom->dom_maxrtkey;
1063 #endif
1064 if (max_keylen == 0) {
1065 log(LOG_ERR,
1066 "rn_init: radix functions require max_keylen be set\n");
1067 return;
1069 R_Malloc(rn_zeros, char *, 2 * max_keylen);
1070 if (rn_zeros == NULL)
1071 panic("rn_init");
1072 bzero(rn_zeros, 2 * max_keylen);
1073 rn_ones = cp = rn_zeros + max_keylen;
1074 cplim = rn_ones + max_keylen;
1075 while (cp < cplim)
1076 *cp++ = -1;
1077 if (rn_inithead((void **)&mask_rnhead, 0) == 0)
1078 panic("rn_init 2");