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1.1 root 1: /*
2: * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3: *
4: * @APPLE_LICENSE_HEADER_START@
5: *
6: * Portions Copyright (c) 1999 Apple Computer, Inc. All Rights
7: * Reserved. This file contains Original Code and/or Modifications of
8: * Original Code as defined in and that are subject to the Apple Public
9: * Source License Version 1.1 (the "License"). You may not use this file
10: * except in compliance with the License. Please obtain a copy of the
11: * License at http://www.apple.com/publicsource and read it before using
12: * this file.
13: *
14: * The Original Code and all software distributed under the License are
15: * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
16: * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
17: * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
18: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
19: * License for the specific language governing rights and limitations
20: * under the License.
21: *
22: * @APPLE_LICENSE_HEADER_END@
23: */
24:
25: /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
26: /*
27: * Copyright (c) 1988, 1989, 1993
28: * The Regents of the University of California. All rights reserved.
29: *
30: * Redistribution and use in source and binary forms, with or without
31: * modification, are permitted provided that the following conditions
32: * are met:
33: * 1. Redistributions of source code must retain the above copyright
34: * notice, this list of conditions and the following disclaimer.
35: * 2. Redistributions in binary form must reproduce the above copyright
36: * notice, this list of conditions and the following disclaimer in the
37: * documentation and/or other materials provided with the distribution.
38: * 3. All advertising materials mentioning features or use of this software
39: * must display the following acknowledgement:
40: * This product includes software developed by the University of
41: * California, Berkeley and its contributors.
42: * 4. Neither the name of the University nor the names of its contributors
43: * may be used to endorse or promote products derived from this software
44: * without specific prior written permission.
45: *
46: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
47: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
50: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56: * SUCH DAMAGE.
57: *
58: * @(#)radix.c 8.5 (Berkeley) 5/19/95
59: */
60:
61: /*
62: * Routines to build and maintain radix trees for routing lookups.
63: */
64: #ifndef _RADIX_H_
65: #include <sys/param.h>
66: #ifdef KERNEL
67: #include <sys/systm.h>
68: #include <sys/malloc.h>
69: #define M_DONTWAIT M_NOWAIT
70: #include <sys/domain.h>
71: #else
72: #include <stdlib.h>
73: #endif
74: #include <sys/syslog.h>
75: #include <net/radix.h>
76: #endif
77:
78: int max_keylen;
79: struct radix_mask *rn_mkfreelist;
80: struct radix_node_head *mask_rnhead;
81: static char *addmask_key;
82: static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1};
83: static char *rn_zeros, *rn_ones;
84:
85: #define rn_masktop (mask_rnhead->rnh_treetop)
86: #undef Bcmp
87: #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l))
88: /*
89: * The data structure for the keys is a radix tree with one way
90: * branching removed. The index rn_b at an internal node n represents a bit
91: * position to be tested. The tree is arranged so that all descendants
92: * of a node n have keys whose bits all agree up to position rn_b - 1.
93: * (We say the index of n is rn_b.)
94: *
95: * There is at least one descendant which has a one bit at position rn_b,
96: * and at least one with a zero there.
97: *
98: * A route is determined by a pair of key and mask. We require that the
99: * bit-wise logical and of the key and mask to be the key.
100: * We define the index of a route to associated with the mask to be
101: * the first bit number in the mask where 0 occurs (with bit number 0
102: * representing the highest order bit).
103: *
104: * We say a mask is normal if every bit is 0, past the index of the mask.
105: * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b,
106: * and m is a normal mask, then the route applies to every descendant of n.
107: * If the index(m) < rn_b, this implies the trailing last few bits of k
108: * before bit b are all 0, (and hence consequently true of every descendant
109: * of n), so the route applies to all descendants of the node as well.
110: *
111: * Similar logic shows that a non-normal mask m such that
112: * index(m) <= index(n) could potentially apply to many children of n.
113: * Thus, for each non-host route, we attach its mask to a list at an internal
114: * node as high in the tree as we can go.
115: *
116: * The present version of the code makes use of normal routes in short-
117: * circuiting an explict mask and compare operation when testing whether
118: * a key satisfies a normal route, and also in remembering the unique leaf
119: * that governs a subtree.
120: */
121:
122: struct radix_node *
123: rn_search(v_arg, head)
124: void *v_arg;
125: struct radix_node *head;
126: {
127: register struct radix_node *x;
128: register caddr_t v;
129:
130: for (x = head, v = v_arg; x->rn_b >= 0;) {
131: if (x->rn_bmask & v[x->rn_off])
132: x = x->rn_r;
133: else
134: x = x->rn_l;
135: }
136: return (x);
137: };
138:
139: struct radix_node *
140: rn_search_m(v_arg, head, m_arg)
141: struct radix_node *head;
142: void *v_arg, *m_arg;
143: {
144: register struct radix_node *x;
145: register caddr_t v = v_arg, m = m_arg;
146:
147: for (x = head; x->rn_b >= 0;) {
148: if ((x->rn_bmask & m[x->rn_off]) &&
149: (x->rn_bmask & v[x->rn_off]))
150: x = x->rn_r;
151: else
152: x = x->rn_l;
153: }
154: return x;
155: };
156:
157: int
158: rn_refines(m_arg, n_arg)
159: void *m_arg, *n_arg;
160: {
161: register caddr_t m = m_arg, n = n_arg;
162: register caddr_t lim, lim2 = lim = n + *(u_char *)n;
163: int longer = (*(u_char *)n++) - (int)(*(u_char *)m++);
164: int masks_are_equal = 1;
165:
166: if (longer > 0)
167: lim -= longer;
168: while (n < lim) {
169: if (*n & ~(*m))
170: return 0;
171: if (*n++ != *m++)
172: masks_are_equal = 0;
173: }
174: while (n < lim2)
175: if (*n++)
176: return 0;
177: if (masks_are_equal && (longer < 0))
178: for (lim2 = m - longer; m < lim2; )
179: if (*m++)
180: return 1;
181: return (!masks_are_equal);
182: }
183:
184: struct radix_node *
185: rn_lookup(v_arg, m_arg, head)
186: void *v_arg, *m_arg;
187: struct radix_node_head *head;
188: {
189: register struct radix_node *x;
190: caddr_t netmask = 0;
191:
192: if (m_arg) {
193: if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0)
194: return (0);
195: netmask = x->rn_key;
196: }
197: x = rn_match(v_arg, head);
198: if (x && netmask) {
199: while (x && x->rn_mask != netmask)
200: x = x->rn_dupedkey;
201: }
202: return x;
203: }
204:
205: static int
206: rn_satsifies_leaf(trial, leaf, skip)
207: char *trial;
208: register struct radix_node *leaf;
209: int skip;
210: {
211: register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
212: char *cplim;
213: int length = min(*(u_char *)cp, *(u_char *)cp2);
214:
215: if (cp3 == 0)
216: cp3 = rn_ones;
217: else
218: length = min(length, *(u_char *)cp3);
219: cplim = cp + length; cp3 += skip; cp2 += skip;
220: for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
221: if ((*cp ^ *cp2) & *cp3)
222: return 0;
223: return 1;
224: }
225:
226: struct radix_node *
227: rn_match(v_arg, head)
228: void *v_arg;
229: struct radix_node_head *head;
230: {
231: caddr_t v = v_arg;
232: register struct radix_node *t = head->rnh_treetop, *x;
233: register caddr_t cp = v, cp2;
234: caddr_t cplim;
235: struct radix_node *saved_t, *top = t;
236: int off = t->rn_off, vlen = *(u_char *)cp, matched_off;
237: register int test, b, rn_b;
238:
239: /*
240: * Open code rn_search(v, top) to avoid overhead of extra
241: * subroutine call.
242: */
243: for (; t->rn_b >= 0; ) {
244: if (t->rn_bmask & cp[t->rn_off])
245: t = t->rn_r;
246: else
247: t = t->rn_l;
248: }
249: /*
250: * See if we match exactly as a host destination
251: * or at least learn how many bits match, for normal mask finesse.
252: *
253: * It doesn't hurt us to limit how many bytes to check
254: * to the length of the mask, since if it matches we had a genuine
255: * match and the leaf we have is the most specific one anyway;
256: * if it didn't match with a shorter length it would fail
257: * with a long one. This wins big for class B&C netmasks which
258: * are probably the most common case...
259: */
260: if (t->rn_mask)
261: vlen = *(u_char *)t->rn_mask;
262: cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
263: for (; cp < cplim; cp++, cp2++)
264: if (*cp != *cp2)
265: goto on1;
266: /*
267: * This extra grot is in case we are explicitly asked
268: * to look up the default. Ugh!
269: */
270: if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey)
271: t = t->rn_dupedkey;
272: return t;
273: on1:
274: test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
275: for (b = 7; (test >>= 1) > 0;)
276: b--;
277: matched_off = cp - v;
278: b += matched_off << 3;
279: rn_b = -1 - b;
280: /*
281: * If there is a host route in a duped-key chain, it will be first.
282: */
283: if ((saved_t = t)->rn_mask == 0)
284: t = t->rn_dupedkey;
285: for (; t; t = t->rn_dupedkey)
286: /*
287: * Even if we don't match exactly as a host,
288: * we may match if the leaf we wound up at is
289: * a route to a net.
290: */
291: if (t->rn_flags & RNF_NORMAL) {
292: if (rn_b <= t->rn_b)
293: return t;
294: } else if (rn_satsifies_leaf(v, t, matched_off))
295: return t;
296: t = saved_t;
297: /* start searching up the tree */
298: do {
299: register struct radix_mask *m;
300: t = t->rn_p;
301: m = t->rn_mklist;
302: if (m) {
303: /*
304: * If non-contiguous masks ever become important
305: * we can restore the masking and open coding of
306: * the search and satisfaction test and put the
307: * calculation of "off" back before the "do".
308: */
309: do {
310: if (m->rm_flags & RNF_NORMAL) {
311: if (rn_b <= m->rm_b)
312: return (m->rm_leaf);
313: } else {
314: off = min(t->rn_off, matched_off);
315: x = rn_search_m(v, t, m->rm_mask);
316: while (x && x->rn_mask != m->rm_mask)
317: x = x->rn_dupedkey;
318: if (x && rn_satsifies_leaf(v, x, off))
319: return x;
320: }
321: m = m->rm_mklist;
322: } while (m);
323: }
324: } while (t != top);
325: return 0;
326: };
327:
328: #ifdef RN_DEBUG
329: int rn_nodenum;
330: struct radix_node *rn_clist;
331: int rn_saveinfo;
332: int rn_debug = 1;
333: #endif
334:
335: struct radix_node *
336: rn_newpair(v, b, nodes)
337: void *v;
338: int b;
339: struct radix_node nodes[2];
340: {
341: register struct radix_node *tt = nodes, *t = tt + 1;
342: t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7);
343: t->rn_l = tt; t->rn_off = b >> 3;
344: tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t;
345: tt->rn_flags = t->rn_flags = RNF_ACTIVE;
346: #ifdef RN_DEBUG
347: tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
348: tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
349: #endif
350: return t;
351: }
352:
353: struct radix_node *
354: rn_insert(v_arg, head, dupentry, nodes)
355: void *v_arg;
356: struct radix_node_head *head;
357: int *dupentry;
358: struct radix_node nodes[2];
359: {
360: caddr_t v = v_arg;
361: struct radix_node *top = head->rnh_treetop;
362: int head_off = top->rn_off, vlen = (int)*((u_char *)v);
363: register struct radix_node *t = rn_search(v_arg, top);
364: register caddr_t cp = v + head_off;
365: register int b;
366: struct radix_node *tt;
367: /*
368: * Find first bit at which v and t->rn_key differ
369: */
370: {
371: register caddr_t cp2 = t->rn_key + head_off;
372: register int cmp_res;
373: caddr_t cplim = v + vlen;
374:
375: while (cp < cplim)
376: if (*cp2++ != *cp++)
377: goto on1;
378: *dupentry = 1;
379: return t;
380: on1:
381: *dupentry = 0;
382: cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
383: for (b = (cp - v) << 3; cmp_res; b--)
384: cmp_res >>= 1;
385: }
386: {
387: register struct radix_node *p, *x = top;
388: cp = v;
389: do {
390: p = x;
391: if (cp[x->rn_off] & x->rn_bmask)
392: x = x->rn_r;
393: else x = x->rn_l;
394: } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */
395: #ifdef RN_DEBUG
396: if (rn_debug)
397: log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
398: #endif
399: t = rn_newpair(v_arg, b, nodes); tt = t->rn_l;
400: if ((cp[p->rn_off] & p->rn_bmask) == 0)
401: p->rn_l = t;
402: else
403: p->rn_r = t;
404: x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */
405: if ((cp[t->rn_off] & t->rn_bmask) == 0) {
406: t->rn_r = x;
407: } else {
408: t->rn_r = tt; t->rn_l = x;
409: }
410: #ifdef RN_DEBUG
411: if (rn_debug)
412: log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
413: #endif
414: }
415: return (tt);
416: }
417:
418: struct radix_node *
419: rn_addmask(n_arg, search, skip)
420: int search, skip;
421: void *n_arg;
422: {
423: caddr_t netmask = (caddr_t)n_arg;
424: register struct radix_node *x;
425: register caddr_t cp, cplim;
426: register int b = 0, mlen, j;
427: int maskduplicated, m0, isnormal;
428: struct radix_node *saved_x;
429: static int last_zeroed = 0;
430:
431: if ((mlen = *(u_char *)netmask) > max_keylen)
432: mlen = max_keylen;
433: if (skip == 0)
434: skip = 1;
435: if (mlen <= skip)
436: return (mask_rnhead->rnh_nodes);
437: if (skip > 1)
438: Bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
439: if ((m0 = mlen) > skip)
440: Bcopy(netmask + skip, addmask_key + skip, mlen - skip);
441: /*
442: * Trim trailing zeroes.
443: */
444: for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
445: cp--;
446: mlen = cp - addmask_key;
447: if (mlen <= skip) {
448: if (m0 >= last_zeroed)
449: last_zeroed = mlen;
450: return (mask_rnhead->rnh_nodes);
451: }
452: if (m0 < last_zeroed)
453: Bzero(addmask_key + m0, last_zeroed - m0);
454: *addmask_key = last_zeroed = mlen;
455: x = rn_search(addmask_key, rn_masktop);
456: if (Bcmp(addmask_key, x->rn_key, mlen) != 0)
457: x = 0;
458: if (x || search)
459: return (x);
460: R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x));
461: if ((saved_x = x) == 0)
462: return (0);
463: Bzero(x, max_keylen + 2 * sizeof (*x));
464: netmask = cp = (caddr_t)(x + 2);
465: Bcopy(addmask_key, cp, mlen);
466: x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
467: if (maskduplicated) {
468: log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
469: Free(saved_x);
470: return (x);
471: }
472: /*
473: * Calculate index of mask, and check for normalcy.
474: */
475: cplim = netmask + mlen; isnormal = 1;
476: for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;)
477: cp++;
478: if (cp != cplim) {
479: for (j = 0x80; (j & *cp) != 0; j >>= 1)
480: b++;
481: if (*cp != normal_chars[b] || cp != (cplim - 1))
482: isnormal = 0;
483: }
484: b += (cp - netmask) << 3;
485: x->rn_b = -1 - b;
486: if (isnormal)
487: x->rn_flags |= RNF_NORMAL;
488: return (x);
489: }
490:
491: static int /* XXX: arbitrary ordering for non-contiguous masks */
492: rn_lexobetter(m_arg, n_arg)
493: void *m_arg, *n_arg;
494: {
495: register u_char *mp = m_arg, *np = n_arg, *lim;
496:
497: if (*mp > *np)
498: return 1; /* not really, but need to check longer one first */
499: if (*mp == *np)
500: for (lim = mp + *mp; mp < lim;)
501: if (*mp++ > *np++)
502: return 1;
503: return 0;
504: }
505:
506: static struct radix_mask *
507: rn_new_radix_mask(tt, next)
508: register struct radix_node *tt;
509: register struct radix_mask *next;
510: {
511: register struct radix_mask *m;
512:
513: MKGet(m);
514: if (m == 0) {
515: log(LOG_ERR, "Mask for route not entered\n");
516: return (0);
517: }
518: Bzero(m, sizeof *m);
519: m->rm_b = tt->rn_b;
520: m->rm_flags = tt->rn_flags;
521: if (tt->rn_flags & RNF_NORMAL)
522: m->rm_leaf = tt;
523: else
524: m->rm_mask = tt->rn_mask;
525: m->rm_mklist = next;
526: tt->rn_mklist = m;
527: return m;
528: }
529:
530: struct radix_node *
531: rn_addroute(v_arg, n_arg, head, treenodes)
532: void *v_arg, *n_arg;
533: struct radix_node_head *head;
534: struct radix_node treenodes[2];
535: {
536: caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg;
537: register struct radix_node *t, *x = 0, *tt;
538: struct radix_node *saved_tt, *top = head->rnh_treetop;
539: short b = 0, b_leaf = 0;
540: int keyduplicated;
541: caddr_t mmask;
542: struct radix_mask *m, **mp;
543:
544: /*
545: * In dealing with non-contiguous masks, there may be
546: * many different routes which have the same mask.
547: * We will find it useful to have a unique pointer to
548: * the mask to speed avoiding duplicate references at
549: * nodes and possibly save time in calculating indices.
550: */
551: if (netmask) {
552: if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0)
553: return (0);
554: b_leaf = x->rn_b;
555: b = -1 - x->rn_b;
556: netmask = x->rn_key;
557: }
558: /*
559: * Deal with duplicated keys: attach node to previous instance
560: */
561: saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes);
562: if (keyduplicated) {
563: for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
564: if (tt->rn_mask == netmask)
565: return (0);
566: if (netmask == 0 ||
567: (tt->rn_mask &&
568: ((b_leaf < tt->rn_b) || /* index(netmask) > node */
569: rn_refines(netmask, tt->rn_mask) ||
570: rn_lexobetter(netmask, tt->rn_mask))))
571: break;
572: }
573: /*
574: * If the mask is not duplicated, we wouldn't
575: * find it among possible duplicate key entries
576: * anyway, so the above test doesn't hurt.
577: *
578: * We sort the masks for a duplicated key the same way as
579: * in a masklist -- most specific to least specific.
580: * This may require the unfortunate nuisance of relocating
581: * the head of the list.
582: *
583: * We also reverse, or doubly link the list through the
584: * parent pointer.
585: */
586: if (tt == saved_tt) {
587: struct radix_node *xx = x;
588: /* link in at head of list */
589: (tt = treenodes)->rn_dupedkey = t;
590: tt->rn_flags = t->rn_flags;
591: tt->rn_p = x = t->rn_p;
592: t->rn_p = tt;
593: if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt;
594: saved_tt = tt; x = xx;
595: } else {
596: (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
597: t->rn_dupedkey = tt;
598: tt->rn_p = t;
599: if (tt->rn_dupedkey)
600: tt->rn_dupedkey->rn_p = tt;
601: }
602: #ifdef RN_DEBUG
603: t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
604: tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
605: #endif
606: tt->rn_key = (caddr_t) v;
607: tt->rn_b = -1;
608: tt->rn_flags = RNF_ACTIVE;
609: }
610: /*
611: * Put mask in tree.
612: */
613: if (netmask) {
614: tt->rn_mask = netmask;
615: tt->rn_b = x->rn_b;
616: tt->rn_flags |= x->rn_flags & RNF_NORMAL;
617: }
618: t = saved_tt->rn_p;
619: if (keyduplicated)
620: goto on2;
621: b_leaf = -1 - t->rn_b;
622: if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r;
623: /* Promote general routes from below */
624: if (x->rn_b < 0) {
625: for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
626: if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) {
627: *mp = m = rn_new_radix_mask(x, 0);
628: if (m)
629: mp = &m->rm_mklist;
630: }
631: } else if (x->rn_mklist) {
632: /*
633: * Skip over masks whose index is > that of new node
634: */
635: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
636: if (m->rm_b >= b_leaf)
637: break;
638: t->rn_mklist = m; *mp = 0;
639: }
640: on2:
641: /* Add new route to highest possible ancestor's list */
642: if ((netmask == 0) || (b > t->rn_b ))
643: return tt; /* can't lift at all */
644: b_leaf = tt->rn_b;
645: do {
646: x = t;
647: t = t->rn_p;
648: } while (b <= t->rn_b && x != top);
649: /*
650: * Search through routes associated with node to
651: * insert new route according to index.
652: * Need same criteria as when sorting dupedkeys to avoid
653: * double loop on deletion.
654: */
655: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
656: if (m->rm_b < b_leaf)
657: continue;
658: if (m->rm_b > b_leaf)
659: break;
660: if (m->rm_flags & RNF_NORMAL) {
661: mmask = m->rm_leaf->rn_mask;
662: if (tt->rn_flags & RNF_NORMAL) {
663: log(LOG_ERR,
664: "Non-unique normal route, mask not entered");
665: return tt;
666: }
667: } else
668: mmask = m->rm_mask;
669: if (mmask == netmask) {
670: m->rm_refs++;
671: tt->rn_mklist = m;
672: return tt;
673: }
674: if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask))
675: break;
676: }
677: *mp = rn_new_radix_mask(tt, *mp);
678: return tt;
679: }
680:
681: struct radix_node *
682: rn_delete(v_arg, netmask_arg, head)
683: void *v_arg, *netmask_arg;
684: struct radix_node_head *head;
685: {
686: register struct radix_node *t, *p, *x, *tt;
687: struct radix_mask *m, *saved_m, **mp;
688: struct radix_node *dupedkey, *saved_tt, *top;
689: caddr_t v, netmask;
690: int b, head_off, vlen;
691:
692: v = v_arg;
693: netmask = netmask_arg;
694: x = head->rnh_treetop;
695: tt = rn_search(v, x);
696: head_off = x->rn_off;
697: vlen = *(u_char *)v;
698: saved_tt = tt;
699: top = x;
700: if (tt == 0 ||
701: Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
702: return (0);
703: /*
704: * Delete our route from mask lists.
705: */
706: if (netmask) {
707: if ((x = rn_addmask(netmask, 1, head_off)) == 0)
708: return (0);
709: netmask = x->rn_key;
710: while (tt->rn_mask != netmask)
711: if ((tt = tt->rn_dupedkey) == 0)
712: return (0);
713: }
714: if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0)
715: goto on1;
716: if (tt->rn_flags & RNF_NORMAL) {
717: if (m->rm_leaf != tt || m->rm_refs > 0) {
718: log(LOG_ERR, "rn_delete: inconsistent annotation\n");
719: return 0; /* dangling ref could cause disaster */
720: }
721: } else {
722: if (m->rm_mask != tt->rn_mask) {
723: log(LOG_ERR, "rn_delete: inconsistent annotation\n");
724: goto on1;
725: }
726: if (--m->rm_refs >= 0)
727: goto on1;
728: }
729: b = -1 - tt->rn_b;
730: t = saved_tt->rn_p;
731: if (b > t->rn_b)
732: goto on1; /* Wasn't lifted at all */
733: do {
734: x = t;
735: t = t->rn_p;
736: } while (b <= t->rn_b && x != top);
737: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
738: if (m == saved_m) {
739: *mp = m->rm_mklist;
740: MKFree(m);
741: break;
742: }
743: if (m == 0) {
744: log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
745: if (tt->rn_flags & RNF_NORMAL)
746: return (0); /* Dangling ref to us */
747: }
748: on1:
749: /*
750: * Eliminate us from tree
751: */
752: if (tt->rn_flags & RNF_ROOT)
753: return (0);
754: #ifdef RN_DEBUG
755: /* Get us out of the creation list */
756: for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
757: if (t) t->rn_ybro = tt->rn_ybro;
758: #endif
759: t = tt->rn_p;
760: dupedkey = saved_tt->rn_dupedkey;
761: if (dupedkey) {
762: /*
763: * Here, tt is the deletion target, and
764: * saved_tt is the head of the dupedkey chain.
765: */
766: if (tt == saved_tt) {
767: x = dupedkey; x->rn_p = t;
768: if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x;
769: } else {
770: /* find node in front of tt on the chain */
771: for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
772: p = p->rn_dupedkey;
773: if (p) {
774: p->rn_dupedkey = tt->rn_dupedkey;
775: if (tt->rn_dupedkey)
776: tt->rn_dupedkey->rn_p = p;
777: } else log(LOG_ERR, "rn_delete: couldn't find us\n");
778: }
779: t = tt + 1;
780: if (t->rn_flags & RNF_ACTIVE) {
781: #ifndef RN_DEBUG
782: *++x = *t; p = t->rn_p;
783: #else
784: b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p;
785: #endif
786: if (p->rn_l == t) p->rn_l = x; else p->rn_r = x;
787: x->rn_l->rn_p = x; x->rn_r->rn_p = x;
788: }
789: goto out;
790: }
791: if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l;
792: p = t->rn_p;
793: if (p->rn_r == t) p->rn_r = x; else p->rn_l = x;
794: x->rn_p = p;
795: /*
796: * Demote routes attached to us.
797: */
798: if (t->rn_mklist) {
799: if (x->rn_b >= 0) {
800: for (mp = &x->rn_mklist; (m = *mp);)
801: mp = &m->rm_mklist;
802: *mp = t->rn_mklist;
803: } else {
804: /* If there are any key,mask pairs in a sibling
805: duped-key chain, some subset will appear sorted
806: in the same order attached to our mklist */
807: for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
808: if (m == x->rn_mklist) {
809: struct radix_mask *mm = m->rm_mklist;
810: x->rn_mklist = 0;
811: if (--(m->rm_refs) < 0)
812: MKFree(m);
813: m = mm;
814: }
815: if (m)
816: log(LOG_ERR, "%s %x at %x\n",
817: "rn_delete: Orphaned Mask", m, x);
818: }
819: }
820: /*
821: * We may be holding an active internal node in the tree.
822: */
823: x = tt + 1;
824: if (t != x) {
825: #ifndef RN_DEBUG
826: *t = *x;
827: #else
828: b = t->rn_info; *t = *x; t->rn_info = b;
829: #endif
830: t->rn_l->rn_p = t; t->rn_r->rn_p = t;
831: p = x->rn_p;
832: if (p->rn_l == x) p->rn_l = t; else p->rn_r = t;
833: }
834: out:
835: tt->rn_flags &= ~RNF_ACTIVE;
836: tt[1].rn_flags &= ~RNF_ACTIVE;
837: return (tt);
838: }
839:
840: int
841: rn_walktree(h, f, w)
842: struct radix_node_head *h;
843: register int (*f)();
844: void *w;
845: {
846: int error;
847: struct radix_node *base, *next;
848: register struct radix_node *rn = h->rnh_treetop;
849: /*
850: * This gets complicated because we may delete the node
851: * while applying the function f to it, so we need to calculate
852: * the successor node in advance.
853: */
854: /* First time through node, go left */
855: while (rn->rn_b >= 0)
856: rn = rn->rn_l;
857: for (;;) {
858: base = rn;
859: /* If at right child go back up, otherwise, go right */
860: while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0)
861: rn = rn->rn_p;
862: /* Find the next *leaf* since next node might vanish, too */
863: for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;)
864: rn = rn->rn_l;
865: next = rn;
866: /* Process leaves */
867: while ((rn = base)) {
868: base = rn->rn_dupedkey;
869: if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w)))
870: return (error);
871: }
872: rn = next;
873: if (rn->rn_flags & RNF_ROOT)
874: return (0);
875: }
876: /* NOTREACHED */
877: }
878:
879: int
880: rn_inithead(head, off)
881: void **head;
882: int off;
883: {
884: register struct radix_node_head *rnh;
885: register struct radix_node *t, *tt, *ttt;
886: if (*head)
887: return (1);
888: R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh));
889: if (rnh == 0)
890: return (0);
891: Bzero(rnh, sizeof (*rnh));
892: *head = rnh;
893: t = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
894: ttt = rnh->rnh_nodes + 2;
895: t->rn_r = ttt;
896: t->rn_p = t;
897: tt = t->rn_l;
898: tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
899: tt->rn_b = -1 - off;
900: *ttt = *tt;
901: ttt->rn_key = rn_ones;
902: rnh->rnh_addaddr = rn_addroute;
903: rnh->rnh_deladdr = rn_delete;
904: rnh->rnh_matchaddr = rn_match;
905: rnh->rnh_lookup = rn_lookup;
906: rnh->rnh_walktree = rn_walktree;
907: rnh->rnh_treetop = t;
908: return (1);
909: }
910:
911: void
912: rn_init()
913: {
914: char *cp, *cplim;
915: #ifdef _KERNEL
916: struct domain *dom;
917:
918: for (dom = domains; dom; dom = dom->dom_next)
919: if (dom->dom_maxrtkey > max_keylen)
920: max_keylen = dom->dom_maxrtkey;
921: #endif
922: if (max_keylen == 0) {
923: log(LOG_ERR,
924: "rn_init: radix functions require max_keylen be set\n");
925: return;
926: }
927: R_Malloc(rn_zeros, char *, 3 * max_keylen);
928: if (rn_zeros == NULL)
929: panic("rn_init");
930: Bzero(rn_zeros, 3 * max_keylen);
931: rn_ones = cp = rn_zeros + max_keylen;
932: addmask_key = cplim = rn_ones + max_keylen;
933: while (cp < cplim)
934: *cp++ = -1;
935: if (rn_inithead((void **)&mask_rnhead, 0) == 0)
936: panic("rn_init 2");
937: }
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