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1.1 root 1: /*
2: * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3: *
4: * @APPLE_LICENSE_HEADER_START@
5: *
6: * The contents of this file constitute Original Code as defined in and
7: * are subject to the Apple Public Source License Version 1.1 (the
8: * "License"). You may not use this file except in compliance with the
9: * License. Please obtain a copy of the License at
10: * http://www.apple.com/publicsource and read it before using this file.
11: *
12: * This Original Code and all software distributed under the License are
13: * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14: * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15: * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17: * License for the specific language governing rights and limitations
18: * under the License.
19: *
20: * @APPLE_LICENSE_HEADER_END@
21: */
22: /*
23: * Copyright (c) 1988, 1989, 1993
24: * The Regents of the University of California. All rights reserved.
25: *
26: * Redistribution and use in source and binary forms, with or without
27: * modification, are permitted provided that the following conditions
28: * are met:
29: * 1. Redistributions of source code must retain the above copyright
30: * notice, this list of conditions and the following disclaimer.
31: * 2. Redistributions in binary form must reproduce the above copyright
32: * notice, this list of conditions and the following disclaimer in the
33: * documentation and/or other materials provided with the distribution.
34: * 3. All advertising materials mentioning features or use of this software
35: * must display the following acknowledgement:
36: * This product includes software developed by the University of
37: * California, Berkeley and its contributors.
38: * 4. Neither the name of the University nor the names of its contributors
39: * may be used to endorse or promote products derived from this software
40: * without specific prior written permission.
41: *
42: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
43: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
44: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
45: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
46: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
47: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
48: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
49: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
50: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
51: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52: * SUCH DAMAGE.
53: *
54: * @(#)radix.c 8.4 (Berkeley) 11/2/94
55: */
56:
57: /*
58: * Routines to build and maintain radix trees for routing lookups.
59: */
60: #ifndef _RADIX_H_
61: #include <sys/param.h>
62: #ifdef KERNEL
63: #include <sys/systm.h>
64: #include <sys/malloc.h>
65: #define M_DONTWAIT M_NOWAIT
66: #include <sys/domain.h>
67: #else
68: #include <stdlib.h>
69: #endif
70: #include <sys/syslog.h>
71: #include <net/radix.h>
72: #endif
73:
74: static int rn_walktree_from __P((struct radix_node_head *h, void *a,
75: void *m, walktree_f_t *f, void *w));
76: static int rn_walktree __P((struct radix_node_head *, walktree_f_t *, void *));
77: static struct radix_node
78: *rn_insert __P((void *, struct radix_node_head *, int *,
79: struct radix_node [2])),
80: *rn_newpair __P((void *, int, struct radix_node[2])),
81: *rn_search __P((void *, struct radix_node *)),
82: *rn_search_m __P((void *, struct radix_node *, void *));
83:
84: static int max_keylen;
85: static struct radix_mask *rn_mkfreelist;
86: static struct radix_node_head *mask_rnhead;
87: static char *addmask_key;
88: static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1};
89: static char *rn_zeros, *rn_ones;
90:
91: #define rn_masktop (mask_rnhead->rnh_treetop)
92: #undef Bcmp
93: #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l))
94:
95: static int rn_lexobetter __P((void *m_arg, void *n_arg));
96: static struct radix_mask *
97: rn_new_radix_mask __P((struct radix_node *tt,
98: struct radix_mask *next));
99: static int rn_satsifies_leaf __P((char *trial, struct radix_node *leaf,
100: int skip));
101:
102: /*
103: * The data structure for the keys is a radix tree with one way
104: * branching removed. The index rn_b 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_b - 1.
107: * (We say the index of n is rn_b.)
108: *
109: * There is at least one descendant which has a one bit at position rn_b,
110: * and at least one with a zero there.
111: *
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).
117: *
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_b,
120: * and m is a normal mask, then the route applies to every descendant of n.
121: * If the index(m) < rn_b, 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.
124: *
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.
129: *
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.
134: */
135:
136: static struct radix_node *
137: rn_search(v_arg, head)
138: void *v_arg;
139: struct radix_node *head;
140: {
141: register struct radix_node *x;
142: register caddr_t v;
143:
144: for (x = head, v = v_arg; x->rn_b >= 0;) {
145: if (x->rn_bmask & v[x->rn_off])
146: x = x->rn_r;
147: else
148: x = x->rn_l;
149: }
150: return (x);
151: }
152:
153: static struct radix_node *
154: rn_search_m(v_arg, head, m_arg)
155: struct radix_node *head;
156: void *v_arg, *m_arg;
157: {
158: register struct radix_node *x;
159: register caddr_t v = v_arg, m = m_arg;
160:
161: for (x = head; x->rn_b >= 0;) {
162: if ((x->rn_bmask & m[x->rn_off]) &&
163: (x->rn_bmask & v[x->rn_off]))
164: x = x->rn_r;
165: else
166: x = x->rn_l;
167: }
168: return x;
169: }
170:
171: int
172: rn_refines(m_arg, n_arg)
173: void *m_arg, *n_arg;
174: {
175: register caddr_t m = m_arg, n = n_arg;
176: register caddr_t lim, lim2 = lim = n + *(u_char *)n;
177: int longer = (*(u_char *)n++) - (int)(*(u_char *)m++);
178: int masks_are_equal = 1;
179:
180: if (longer > 0)
181: lim -= longer;
182: while (n < lim) {
183: if (*n & ~(*m))
184: return 0;
185: if (*n++ != *m++)
186: masks_are_equal = 0;
187: }
188: while (n < lim2)
189: if (*n++)
190: return 0;
191: if (masks_are_equal && (longer < 0))
192: for (lim2 = m - longer; m < lim2; )
193: if (*m++)
194: return 1;
195: return (!masks_are_equal);
196: }
197:
198: struct radix_node *
199: rn_lookup(v_arg, m_arg, head)
200: void *v_arg, *m_arg;
201: struct radix_node_head *head;
202: {
203: register struct radix_node *x;
204: caddr_t netmask = 0;
205:
206: if (m_arg) {
207: if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0)
208: return (0);
209: netmask = x->rn_key;
210: }
211: x = rn_match(v_arg, head);
212: if (x && netmask) {
213: while (x && x->rn_mask != netmask)
214: x = x->rn_dupedkey;
215: }
216: return x;
217: }
218:
219: static int
220: rn_satsifies_leaf(trial, leaf, skip)
221: char *trial;
222: register struct radix_node *leaf;
223: int skip;
224: {
225: register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
226: char *cplim;
227: int length = min(*(u_char *)cp, *(u_char *)cp2);
228:
229: if (cp3 == 0)
230: cp3 = rn_ones;
231: else
232: length = min(length, *(u_char *)cp3);
233: cplim = cp + length; cp3 += skip; cp2 += skip;
234: for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
235: if ((*cp ^ *cp2) & *cp3)
236: return 0;
237: return 1;
238: }
239:
240: struct radix_node *
241: rn_match(v_arg, head)
242: void *v_arg;
243: struct radix_node_head *head;
244: {
245: caddr_t v = v_arg;
246: register struct radix_node *t = head->rnh_treetop, *x;
247: register caddr_t cp = v, cp2;
248: caddr_t cplim;
249: struct radix_node *saved_t, *top = t;
250: int off = t->rn_off, vlen = *(u_char *)cp, matched_off;
251: register int test, b, rn_b;
252:
253: /*
254: * Open code rn_search(v, top) to avoid overhead of extra
255: * subroutine call.
256: */
257: for (; t->rn_b >= 0; ) {
258: if (t->rn_bmask & cp[t->rn_off])
259: t = t->rn_r;
260: else
261: t = t->rn_l;
262: }
263: /*
264: * See if we match exactly as a host destination
265: * or at least learn how many bits match, for normal mask finesse.
266: *
267: * It doesn't hurt us to limit how many bytes to check
268: * to the length of the mask, since if it matches we had a genuine
269: * match and the leaf we have is the most specific one anyway;
270: * if it didn't match with a shorter length it would fail
271: * with a long one. This wins big for class B&C netmasks which
272: * are probably the most common case...
273: */
274: if (t->rn_mask)
275: vlen = *(u_char *)t->rn_mask;
276: cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
277: for (; cp < cplim; cp++, cp2++)
278: if (*cp != *cp2)
279: goto on1;
280: /*
281: * This extra grot is in case we are explicitly asked
282: * to look up the default. Ugh!
283: */
284: if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey)
285: t = t->rn_dupedkey;
286: return t;
287: on1:
288: test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
289: for (b = 7; (test >>= 1) > 0;)
290: b--;
291: matched_off = cp - v;
292: b += matched_off << 3;
293: rn_b = -1 - b;
294: /*
295: * If there is a host route in a duped-key chain, it will be first.
296: */
297: if ((saved_t = t)->rn_mask == 0)
298: t = t->rn_dupedkey;
299: for (; t; t = t->rn_dupedkey)
300: /*
301: * Even if we don't match exactly as a host,
302: * we may match if the leaf we wound up at is
303: * a route to a net.
304: */
305: if (t->rn_flags & RNF_NORMAL) {
306: if (rn_b <= t->rn_b)
307: return t;
308: } else if (rn_satsifies_leaf(v, t, matched_off))
309: return t;
310: t = saved_t;
311: /* start searching up the tree */
312: do {
313: register struct radix_mask *m;
314: t = t->rn_p;
315: m = t->rn_mklist;
316: if (m) {
317: /*
318: * If non-contiguous masks ever become important
319: * we can restore the masking and open coding of
320: * the search and satisfaction test and put the
321: * calculation of "off" back before the "do".
322: */
323: do {
324: if (m->rm_flags & RNF_NORMAL) {
325: if (rn_b <= m->rm_b)
326: return (m->rm_leaf);
327: } else {
328: off = min(t->rn_off, matched_off);
329: x = rn_search_m(v, t, m->rm_mask);
330: while (x && x->rn_mask != m->rm_mask)
331: x = x->rn_dupedkey;
332: if (x && rn_satsifies_leaf(v, x, off))
333: return x;
334: }
335: m = m->rm_mklist;
336: } while (m);
337: }
338: } while (t != top);
339: return 0;
340: }
341:
342: #ifdef RN_DEBUG
343: int rn_nodenum;
344: struct radix_node *rn_clist;
345: int rn_saveinfo;
346: int rn_debug = 1;
347: #endif
348:
349: static struct radix_node *
350: rn_newpair(v, b, nodes)
351: void *v;
352: int b;
353: struct radix_node nodes[2];
354: {
355: register struct radix_node *tt = nodes, *t = tt + 1;
356: t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7);
357: t->rn_l = tt; t->rn_off = b >> 3;
358: tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t;
359: tt->rn_flags = t->rn_flags = RNF_ACTIVE;
360: #ifdef RN_DEBUG
361: tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
362: tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
363: #endif
364: return t;
365: }
366:
367: static struct radix_node *
368: rn_insert(v_arg, head, dupentry, nodes)
369: void *v_arg;
370: struct radix_node_head *head;
371: int *dupentry;
372: struct radix_node nodes[2];
373: {
374: caddr_t v = v_arg;
375: struct radix_node *top = head->rnh_treetop;
376: int head_off = top->rn_off, vlen = (int)*((u_char *)v);
377: register struct radix_node *t = rn_search(v_arg, top);
378: register caddr_t cp = v + head_off;
379: register int b;
380: struct radix_node *tt;
381: /*
382: * Find first bit at which v and t->rn_key differ
383: */
384: {
385: register caddr_t cp2 = t->rn_key + head_off;
386: register int cmp_res;
387: caddr_t cplim = v + vlen;
388:
389: while (cp < cplim)
390: if (*cp2++ != *cp++)
391: goto on1;
392: *dupentry = 1;
393: return t;
394: on1:
395: *dupentry = 0;
396: cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
397: for (b = (cp - v) << 3; cmp_res; b--)
398: cmp_res >>= 1;
399: }
400: {
401: register struct radix_node *p, *x = top;
402: cp = v;
403: do {
404: p = x;
405: if (cp[x->rn_off] & x->rn_bmask)
406: x = x->rn_r;
407: else x = x->rn_l;
408: } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */
409: #ifdef RN_DEBUG
410: if (rn_debug)
411: log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
412: #endif
413: t = rn_newpair(v_arg, b, nodes); tt = t->rn_l;
414: if ((cp[p->rn_off] & p->rn_bmask) == 0)
415: p->rn_l = t;
416: else
417: p->rn_r = t;
418: x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */
419: if ((cp[t->rn_off] & t->rn_bmask) == 0) {
420: t->rn_r = x;
421: } else {
422: t->rn_r = tt; t->rn_l = x;
423: }
424: #ifdef RN_DEBUG
425: if (rn_debug)
426: log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
427: #endif
428: }
429: return (tt);
430: }
431:
432: struct radix_node *
433: rn_addmask(n_arg, search, skip)
434: int search, skip;
435: void *n_arg;
436: {
437: caddr_t netmask = (caddr_t)n_arg;
438: register struct radix_node *x;
439: register caddr_t cp, cplim;
440: register int b = 0, mlen, j;
441: int maskduplicated, m0, isnormal;
442: struct radix_node *saved_x;
443: static int last_zeroed = 0;
444:
445: if ((mlen = *(u_char *)netmask) > max_keylen)
446: mlen = max_keylen;
447: if (skip == 0)
448: skip = 1;
449: if (mlen <= skip)
450: return (mask_rnhead->rnh_nodes);
451: if (skip > 1)
452: Bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
453: if ((m0 = mlen) > skip)
454: Bcopy(netmask + skip, addmask_key + skip, mlen - skip);
455: /*
456: * Trim trailing zeroes.
457: */
458: for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
459: cp--;
460: mlen = cp - addmask_key;
461: if (mlen <= skip) {
462: if (m0 >= last_zeroed)
463: last_zeroed = mlen;
464: return (mask_rnhead->rnh_nodes);
465: }
466: if (m0 < last_zeroed)
467: Bzero(addmask_key + m0, last_zeroed - m0);
468: *addmask_key = last_zeroed = mlen;
469: x = rn_search(addmask_key, rn_masktop);
470: if (Bcmp(addmask_key, x->rn_key, mlen) != 0)
471: x = 0;
472: if (x || search)
473: return (x);
474: R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x));
475: if ((saved_x = x) == 0)
476: return (0);
477: Bzero(x, max_keylen + 2 * sizeof (*x));
478: netmask = cp = (caddr_t)(x + 2);
479: Bcopy(addmask_key, cp, mlen);
480: x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
481: if (maskduplicated) {
482: log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
483: Free(saved_x);
484: return (x);
485: }
486: /*
487: * Calculate index of mask, and check for normalcy.
488: */
489: cplim = netmask + mlen; isnormal = 1;
490: for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;)
491: cp++;
492: if (cp != cplim) {
493: for (j = 0x80; (j & *cp) != 0; j >>= 1)
494: b++;
495: if (*cp != normal_chars[b] || cp != (cplim - 1))
496: isnormal = 0;
497: }
498: b += (cp - netmask) << 3;
499: x->rn_b = -1 - b;
500: if (isnormal)
501: x->rn_flags |= RNF_NORMAL;
502: return (x);
503: }
504:
505: static int /* XXX: arbitrary ordering for non-contiguous masks */
506: rn_lexobetter(m_arg, n_arg)
507: void *m_arg, *n_arg;
508: {
509: register u_char *mp = m_arg, *np = n_arg, *lim;
510:
511: if (*mp > *np)
512: return 1; /* not really, but need to check longer one first */
513: if (*mp == *np)
514: for (lim = mp + *mp; mp < lim;)
515: if (*mp++ > *np++)
516: return 1;
517: return 0;
518: }
519:
520: static struct radix_mask *
521: rn_new_radix_mask(tt, next)
522: register struct radix_node *tt;
523: register struct radix_mask *next;
524: {
525: register struct radix_mask *m;
526:
527: MKGet(m);
528: if (m == 0) {
529: log(LOG_ERR, "Mask for route not entered\n");
530: return (0);
531: }
532: Bzero(m, sizeof *m);
533: m->rm_b = tt->rn_b;
534: m->rm_flags = tt->rn_flags;
535: if (tt->rn_flags & RNF_NORMAL)
536: m->rm_leaf = tt;
537: else
538: m->rm_mask = tt->rn_mask;
539: m->rm_mklist = next;
540: tt->rn_mklist = m;
541: return m;
542: }
543:
544: struct radix_node *
545: rn_addroute(v_arg, n_arg, head, treenodes)
546: void *v_arg, *n_arg;
547: struct radix_node_head *head;
548: struct radix_node treenodes[2];
549: {
550: caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg;
551: register struct radix_node *t, *x = 0, *tt;
552: struct radix_node *saved_tt, *top = head->rnh_treetop;
553: short b = 0, b_leaf = 0;
554: int keyduplicated;
555: caddr_t mmask;
556: struct radix_mask *m, **mp;
557:
558: /*
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.
564: */
565: if (netmask) {
566: if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0)
567: return (0);
568: b_leaf = x->rn_b;
569: b = -1 - x->rn_b;
570: netmask = x->rn_key;
571: }
572: /*
573: * Deal with duplicated keys: attach node to previous instance
574: */
575: saved_tt = tt = rn_insert(v, 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 (0);
580: if (netmask == 0 ||
581: (tt->rn_mask &&
582: ((b_leaf < tt->rn_b) || /* index(netmask) > node */
583: rn_refines(netmask, tt->rn_mask) ||
584: rn_lexobetter(netmask, tt->rn_mask))))
585: break;
586: }
587: /*
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.
591: *
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.
596: */
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_p = x = t->rn_p;
603: t->rn_p = tt; /* parent */
604: if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt;
605: saved_tt = tt; x = xx;
606: } else {
607: (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
608: t->rn_dupedkey = tt;
609: tt->rn_p = t; /* parent */
610: if (tt->rn_dupedkey) /* parent */
611: tt->rn_dupedkey->rn_p = tt; /* parent */
612: }
613: #ifdef RN_DEBUG
614: t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
615: tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
616: #endif
617: tt->rn_key = (caddr_t) v;
618: tt->rn_b = -1;
619: tt->rn_flags = RNF_ACTIVE;
620: }
621: /*
622: * Put mask in tree.
623: */
624: if (netmask) {
625: tt->rn_mask = netmask;
626: tt->rn_b = x->rn_b;
627: tt->rn_flags |= x->rn_flags & RNF_NORMAL;
628: }
629: t = saved_tt->rn_p;
630: if (keyduplicated)
631: goto on2;
632: b_leaf = -1 - t->rn_b;
633: if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r;
634: /* Promote general routes from below */
635: if (x->rn_b < 0) {
636: for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
637: if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) {
638: *mp = m = rn_new_radix_mask(x, 0);
639: if (m)
640: mp = &m->rm_mklist;
641: }
642: } else if (x->rn_mklist) {
643: /*
644: * Skip over masks whose index is > that of new node
645: */
646: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
647: if (m->rm_b >= b_leaf)
648: break;
649: t->rn_mklist = m; *mp = 0;
650: }
651: on2:
652: /* Add new route to highest possible ancestor's list */
653: if ((netmask == 0) || (b > t->rn_b ))
654: return tt; /* can't lift at all */
655: b_leaf = tt->rn_b;
656: do {
657: x = t;
658: t = t->rn_p;
659: } while (b <= t->rn_b && x != top);
660: /*
661: * Search through routes associated with node to
662: * insert new route according to index.
663: * Need same criteria as when sorting dupedkeys to avoid
664: * double loop on deletion.
665: */
666: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
667: if (m->rm_b < b_leaf)
668: continue;
669: if (m->rm_b > b_leaf)
670: break;
671: if (m->rm_flags & RNF_NORMAL) {
672: mmask = m->rm_leaf->rn_mask;
673: if (tt->rn_flags & RNF_NORMAL) {
674: log(LOG_ERR,
675: "Non-unique normal route, mask not entered");
676: return tt;
677: }
678: } else
679: mmask = m->rm_mask;
680: if (mmask == netmask) {
681: m->rm_refs++;
682: tt->rn_mklist = m;
683: return tt;
684: }
685: if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask))
686: break;
687: }
688: *mp = rn_new_radix_mask(tt, *mp);
689: return tt;
690: }
691:
692: struct radix_node *
693: rn_delete(v_arg, netmask_arg, head)
694: void *v_arg, *netmask_arg;
695: struct radix_node_head *head;
696: {
697: register struct radix_node *t, *p, *x, *tt;
698: struct radix_mask *m, *saved_m, **mp;
699: struct radix_node *dupedkey, *saved_tt, *top;
700: caddr_t v, netmask;
701: int b, head_off, vlen;
702:
703: v = v_arg;
704: netmask = netmask_arg;
705: x = head->rnh_treetop;
706: tt = rn_search(v, x);
707: head_off = x->rn_off;
708: vlen = *(u_char *)v;
709: saved_tt = tt;
710: top = x;
711: if (tt == 0 ||
712: Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
713: return (0);
714: /*
715: * Delete our route from mask lists.
716: */
717: if (netmask) {
718: if ((x = rn_addmask(netmask, 1, head_off)) == 0)
719: return (0);
720: netmask = x->rn_key;
721: while (tt->rn_mask != netmask)
722: if ((tt = tt->rn_dupedkey) == 0)
723: return (0);
724: }
725: if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0)
726: goto on1;
727: if (tt->rn_flags & RNF_NORMAL) {
728: if (m->rm_leaf != tt || m->rm_refs > 0) {
729: log(LOG_ERR, "rn_delete: inconsistent annotation\n");
730: return 0; /* dangling ref could cause disaster */
731: }
732: } else {
733: if (m->rm_mask != tt->rn_mask) {
734: log(LOG_ERR, "rn_delete: inconsistent annotation\n");
735: goto on1;
736: }
737: if (--m->rm_refs >= 0)
738: goto on1;
739: }
740: b = -1 - tt->rn_b;
741: t = saved_tt->rn_p;
742: if (b > t->rn_b)
743: goto on1; /* Wasn't lifted at all */
744: do {
745: x = t;
746: t = t->rn_p;
747: } while (b <= t->rn_b && x != top);
748: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
749: if (m == saved_m) {
750: *mp = m->rm_mklist;
751: MKFree(m);
752: break;
753: }
754: if (m == 0) {
755: log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
756: if (tt->rn_flags & RNF_NORMAL)
757: return (0); /* Dangling ref to us */
758: }
759: on1:
760: /*
761: * Eliminate us from tree
762: */
763: if (tt->rn_flags & RNF_ROOT)
764: return (0);
765: #ifdef RN_DEBUG
766: /* Get us out of the creation list */
767: for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
768: if (t) t->rn_ybro = tt->rn_ybro;
769: #endif
770: t = tt->rn_p;
771: dupedkey = saved_tt->rn_dupedkey;
772: if (dupedkey) {
773: /*
774: * at this point, tt is the deletion target and saved_tt
775: * is the head of the dupekey chain
776: */
777: if (tt == saved_tt) {
778: /* remove from head of chain */
779: x = dupedkey; x->rn_p = t;
780: if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x;
781: } else {
782: /* find node in front of tt on the chain */
783: for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
784: p = p->rn_dupedkey;
785: if (p) {
786: p->rn_dupedkey = tt->rn_dupedkey;
787: if (tt->rn_dupedkey) /* parent */
788: tt->rn_dupedkey->rn_p = p; /* parent */
789: } else log(LOG_ERR, "rn_delete: couldn't find us\n");
790: }
791: t = tt + 1;
792: if (t->rn_flags & RNF_ACTIVE) {
793: #ifndef RN_DEBUG
794: *++x = *t; p = t->rn_p;
795: #else
796: b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p;
797: #endif
798: if (p->rn_l == t) p->rn_l = x; else p->rn_r = x;
799: x->rn_l->rn_p = x; x->rn_r->rn_p = x;
800: }
801: goto out;
802: }
803: if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l;
804: p = t->rn_p;
805: if (p->rn_r == t) p->rn_r = x; else p->rn_l = x;
806: x->rn_p = p;
807: /*
808: * Demote routes attached to us.
809: */
810: if (t->rn_mklist) {
811: if (x->rn_b >= 0) {
812: for (mp = &x->rn_mklist; (m = *mp);)
813: mp = &m->rm_mklist;
814: *mp = t->rn_mklist;
815: } else {
816: /* If there are any key,mask pairs in a sibling
817: duped-key chain, some subset will appear sorted
818: in the same order attached to our mklist */
819: for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
820: if (m == x->rn_mklist) {
821: struct radix_mask *mm = m->rm_mklist;
822: x->rn_mklist = 0;
823: if (--(m->rm_refs) < 0)
824: MKFree(m);
825: m = mm;
826: }
827: if (m)
828: log(LOG_ERR,
829: "rn_delete: Orphaned Mask %p at %p\n",
830: (void *)m, (void *)x);
831: }
832: }
833: /*
834: * We may be holding an active internal node in the tree.
835: */
836: x = tt + 1;
837: if (t != x) {
838: #ifndef RN_DEBUG
839: *t = *x;
840: #else
841: b = t->rn_info; *t = *x; t->rn_info = b;
842: #endif
843: t->rn_l->rn_p = t; t->rn_r->rn_p = t;
844: p = x->rn_p;
845: if (p->rn_l == x) p->rn_l = t; else p->rn_r = t;
846: }
847: out:
848: tt->rn_flags &= ~RNF_ACTIVE;
849: tt[1].rn_flags &= ~RNF_ACTIVE;
850: return (tt);
851: }
852:
853: /*
854: * This is the same as rn_walktree() except for the parameters and the
855: * exit.
856: */
857: static int
858: rn_walktree_from(h, a, m, f, w)
859: struct radix_node_head *h;
860: void *a, *m;
861: walktree_f_t *f;
862: void *w;
863: {
864: int error;
865: struct radix_node *base, *next;
866: u_char *xa = (u_char *)a;
867: u_char *xm = (u_char *)m;
868: register struct radix_node *rn, *last = 0 /* shut up gcc */;
869: int stopping = 0;
870: int lastb;
871:
872: /*
873: * rn_search_m is sort-of-open-coded here.
874: */
875: /* printf("about to search\n"); */
876: for (rn = h->rnh_treetop; rn->rn_b >= 0; ) {
877: last = rn;
878: /* printf("rn_b %d, rn_bmask %x, xm[rn_off] %x\n",
879: rn->rn_b, rn->rn_bmask, xm[rn->rn_off]); */
880: if (!(rn->rn_bmask & xm[rn->rn_off])) {
881: break;
882: }
883: if (rn->rn_bmask & xa[rn->rn_off]) {
884: rn = rn->rn_r;
885: } else {
886: rn = rn->rn_l;
887: }
888: }
889: /* printf("done searching\n"); */
890:
891: /*
892: * Two cases: either we stepped off the end of our mask,
893: * in which case last == rn, or we reached a leaf, in which
894: * case we want to start from the last node we looked at.
895: * Either way, last is the node we want to start from.
896: */
897: rn = last;
898: lastb = rn->rn_b;
899:
900: /* printf("rn %p, lastb %d\n", rn, lastb);*/
901:
902: /*
903: * This gets complicated because we may delete the node
904: * while applying the function f to it, so we need to calculate
905: * the successor node in advance.
906: */
907: while (rn->rn_b >= 0)
908: rn = rn->rn_l;
909:
910: while (!stopping) {
911: /* printf("node %p (%d)\n", rn, rn->rn_b); */
912: base = rn;
913: /* If at right child go back up, otherwise, go right */
914: while (rn->rn_p->rn_r == rn && !(rn->rn_flags & RNF_ROOT)) {
915: rn = rn->rn_p;
916:
917: /* if went up beyond last, stop */
918: if (rn->rn_b < lastb) {
919: stopping = 1;
920: /* printf("up too far\n"); */
921: }
922: }
923:
924: /* Find the next *leaf* since next node might vanish, too */
925: for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;)
926: rn = rn->rn_l;
927: next = rn;
928: /* Process leaves */
929: while ((rn = base) != 0) {
930: base = rn->rn_dupedkey;
931: /* printf("leaf %p\n", rn); */
932: if (!(rn->rn_flags & RNF_ROOT)
933: && (error = (*f)(rn, w)))
934: return (error);
935: }
936: rn = next;
937:
938: if (rn->rn_flags & RNF_ROOT) {
939: /* printf("root, stopping"); */
940: stopping = 1;
941: }
942:
943: }
944: return 0;
945: }
946:
947: static int
948: rn_walktree(h, f, w)
949: struct radix_node_head *h;
950: walktree_f_t *f;
951: void *w;
952: {
953: int error;
954: struct radix_node *base, *next;
955: register struct radix_node *rn = h->rnh_treetop;
956: /*
957: * This gets complicated because we may delete the node
958: * while applying the function f to it, so we need to calculate
959: * the successor node in advance.
960: */
961: /* First time through node, go left */
962: while (rn->rn_b >= 0)
963: rn = rn->rn_l;
964: for (;;) {
965: base = rn;
966: /* If at right child go back up, otherwise, go right */
967: while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0)
968: rn = rn->rn_p;
969: /* Find the next *leaf* since next node might vanish, too */
970: for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;)
971: rn = rn->rn_l;
972: next = rn;
973: /* Process leaves */
974: while ((rn = base)) {
975: base = rn->rn_dupedkey;
976: if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w)))
977: return (error);
978: }
979: rn = next;
980: if (rn->rn_flags & RNF_ROOT)
981: return (0);
982: }
983: /* NOTREACHED */
984: }
985:
986: int
987: rn_inithead(head, off)
988: void **head;
989: int off;
990: {
991: register struct radix_node_head *rnh;
992: register struct radix_node *t, *tt, *ttt;
993: if (*head)
994: return (1);
995: R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh));
996: if (rnh == 0)
997: return (0);
998: Bzero(rnh, sizeof (*rnh));
999: *head = rnh;
1000: t = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
1001: ttt = rnh->rnh_nodes + 2;
1002: t->rn_r = ttt;
1003: t->rn_p = t;
1004: tt = t->rn_l;
1005: tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
1006: tt->rn_b = -1 - off;
1007: *ttt = *tt;
1008: ttt->rn_key = rn_ones;
1009: rnh->rnh_addaddr = rn_addroute;
1010: rnh->rnh_deladdr = rn_delete;
1011: rnh->rnh_matchaddr = rn_match;
1012: rnh->rnh_lookup = rn_lookup;
1013: rnh->rnh_walktree = rn_walktree;
1014: rnh->rnh_walktree_from = rn_walktree_from;
1015: rnh->rnh_treetop = t;
1016: return (1);
1017: }
1018:
1019: void
1020: rn_init()
1021: {
1022: char *cp, *cplim;
1023: #ifdef KERNEL
1024: struct domain *dom;
1025:
1026: for (dom = domains; dom; dom = dom->dom_next)
1027: if (dom->dom_maxrtkey > max_keylen)
1028: max_keylen = dom->dom_maxrtkey;
1029: #endif
1030: if (max_keylen == 0) {
1031: log(LOG_ERR,
1032: "rn_init: radix functions require max_keylen be set\n");
1033: return;
1034: }
1035: R_Malloc(rn_zeros, char *, 3 * max_keylen);
1036: if (rn_zeros == NULL)
1037: panic("rn_init");
1038: Bzero(rn_zeros, 3 * max_keylen);
1039: rn_ones = cp = rn_zeros + max_keylen;
1040: addmask_key = cplim = rn_ones + max_keylen;
1041: while (cp < cplim)
1042: *cp++ = -1;
1043: if (rn_inithead((void **)&mask_rnhead, 0) == 0)
1044: panic("rn_init 2");
1045: }
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