Annotation of sys/net/radix.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: radix.c,v 1.21 2006/06/18 11:47:45 pascoe Exp $ */
2: /* $NetBSD: radix.c,v 1.20 2003/08/07 16:32:56 agc Exp $ */
3:
4: /*
5: * Copyright (c) 1988, 1989, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * Redistribution and use in source and binary forms, with or without
9: * modification, are permitted provided that the following conditions
10: * are met:
11: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: * 3. Neither the name of the University nor the names of its contributors
17: * may be used to endorse or promote products derived from this software
18: * without specific prior written permission.
19: *
20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30: * SUCH DAMAGE.
31: *
32: * @(#)radix.c 8.6 (Berkeley) 10/17/95
33: */
34:
35: /*
36: * Routines to build and maintain radix trees for routing lookups.
37: */
38:
39: #ifndef _NET_RADIX_H_
40: #include <sys/param.h>
41: #ifdef _KERNEL
42: #include <sys/systm.h>
43: #include <sys/malloc.h>
44: #define M_DONTWAIT M_NOWAIT
45: #include <sys/domain.h>
46: #else
47: #include <stdlib.h>
48: #endif
49: #include <sys/syslog.h>
50: #include <net/radix.h>
51: #endif
52:
53: #ifndef SMALL_KERNEL
54: #include <net/radix_mpath.h>
55: #endif
56:
57: int max_keylen;
58: struct radix_mask *rn_mkfreelist;
59: struct radix_node_head *mask_rnhead;
60: static char *addmask_key;
61: static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1};
62: static char *rn_zeros, *rn_ones;
63:
64: #define rn_masktop (mask_rnhead->rnh_treetop)
65: #undef Bcmp
66: #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l))
67:
68: static int rn_satisfies_leaf(char *, struct radix_node *, int);
69: static int rn_lexobetter(void *, void *);
70: static struct radix_mask *rn_new_radix_mask(struct radix_node *,
71: struct radix_mask *);
72:
73: /*
74: * The data structure for the keys is a radix tree with one way
75: * branching removed. The index rn_b at an internal node n represents a bit
76: * position to be tested. The tree is arranged so that all descendants
77: * of a node n have keys whose bits all agree up to position rn_b - 1.
78: * (We say the index of n is rn_b.)
79: *
80: * There is at least one descendant which has a one bit at position rn_b,
81: * and at least one with a zero there.
82: *
83: * A route is determined by a pair of key and mask. We require that the
84: * bit-wise logical and of the key and mask to be the key.
85: * We define the index of a route to associated with the mask to be
86: * the first bit number in the mask where 0 occurs (with bit number 0
87: * representing the highest order bit).
88: *
89: * We say a mask is normal if every bit is 0, past the index of the mask.
90: * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b,
91: * and m is a normal mask, then the route applies to every descendant of n.
92: * If the index(m) < rn_b, this implies the trailing last few bits of k
93: * before bit b are all 0, (and hence consequently true of every descendant
94: * of n), so the route applies to all descendants of the node as well.
95: *
96: * Similar logic shows that a non-normal mask m such that
97: * index(m) <= index(n) could potentially apply to many children of n.
98: * Thus, for each non-host route, we attach its mask to a list at an internal
99: * node as high in the tree as we can go.
100: *
101: * The present version of the code makes use of normal routes in short-
102: * circuiting an explicit mask and compare operation when testing whether
103: * a key satisfies a normal route, and also in remembering the unique leaf
104: * that governs a subtree.
105: */
106:
107: struct radix_node *
108: rn_search(void *v_arg, struct radix_node *head)
109: {
110: struct radix_node *x;
111: caddr_t v;
112:
113: for (x = head, v = v_arg; x->rn_b >= 0;) {
114: if (x->rn_bmask & v[x->rn_off])
115: x = x->rn_r;
116: else
117: x = x->rn_l;
118: }
119: return (x);
120: }
121:
122: struct radix_node *
123: rn_search_m(void *v_arg, struct radix_node *head, void *m_arg)
124: {
125: struct radix_node *x;
126: caddr_t v = v_arg, m = m_arg;
127:
128: for (x = head; x->rn_b >= 0;) {
129: if ((x->rn_bmask & m[x->rn_off]) &&
130: (x->rn_bmask & v[x->rn_off]))
131: x = x->rn_r;
132: else
133: x = x->rn_l;
134: }
135: return x;
136: }
137:
138: int
139: rn_refines(void *m_arg, void *n_arg)
140: {
141: caddr_t m = m_arg, n = n_arg;
142: caddr_t lim, lim2 = lim = n + *(u_char *)n;
143: int longer = (*(u_char *)n++) - (int)(*(u_char *)m++);
144: int masks_are_equal = 1;
145:
146: if (longer > 0)
147: lim -= longer;
148: while (n < lim) {
149: if (*n & ~(*m))
150: return 0;
151: if (*n++ != *m++)
152: masks_are_equal = 0;
153: }
154: while (n < lim2)
155: if (*n++)
156: return 0;
157: if (masks_are_equal && (longer < 0))
158: for (lim2 = m - longer; m < lim2; )
159: if (*m++)
160: return 1;
161: return (!masks_are_equal);
162: }
163:
164: struct radix_node *
165: rn_lookup(void *v_arg, void *m_arg, struct radix_node_head *head)
166: {
167: struct radix_node *x;
168: caddr_t netmask = 0;
169:
170: if (m_arg) {
171: if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0)
172: return (0);
173: netmask = x->rn_key;
174: }
175: x = rn_match(v_arg, head);
176: if (x && netmask) {
177: while (x && x->rn_mask != netmask)
178: x = x->rn_dupedkey;
179: }
180: return x;
181: }
182:
183: static int
184: rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip)
185: {
186: char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
187: char *cplim;
188: int length = min(*(u_char *)cp, *(u_char *)cp2);
189:
190: if (cp3 == 0)
191: cp3 = rn_ones;
192: else
193: length = min(length, *(u_char *)cp3);
194: cplim = cp + length; cp3 += skip; cp2 += skip;
195: for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
196: if ((*cp ^ *cp2) & *cp3)
197: return 0;
198: return 1;
199: }
200:
201: struct radix_node *
202: rn_match(void *v_arg, struct radix_node_head *head)
203: {
204: caddr_t v = v_arg;
205: struct radix_node *t = head->rnh_treetop, *x;
206: caddr_t cp = v, cp2;
207: caddr_t cplim;
208: struct radix_node *saved_t, *top = t;
209: int off = t->rn_off, vlen = *(u_char *)cp, matched_off;
210: int test, b, rn_b;
211:
212: /*
213: * Open code rn_search(v, top) to avoid overhead of extra
214: * subroutine call.
215: */
216: for (; t->rn_b >= 0; ) {
217: if (t->rn_bmask & cp[t->rn_off])
218: t = t->rn_r;
219: else
220: t = t->rn_l;
221: }
222: /*
223: * See if we match exactly as a host destination
224: * or at least learn how many bits match, for normal mask finesse.
225: *
226: * It doesn't hurt us to limit how many bytes to check
227: * to the length of the mask, since if it matches we had a genuine
228: * match and the leaf we have is the most specific one anyway;
229: * if it didn't match with a shorter length it would fail
230: * with a long one. This wins big for class B&C netmasks which
231: * are probably the most common case...
232: */
233: if (t->rn_mask)
234: vlen = *(u_char *)t->rn_mask;
235: cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
236: for (; cp < cplim; cp++, cp2++)
237: if (*cp != *cp2)
238: goto on1;
239: /*
240: * This extra grot is in case we are explicitly asked
241: * to look up the default. Ugh!
242: */
243: if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey)
244: t = t->rn_dupedkey;
245: return t;
246: on1:
247: test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
248: for (b = 7; (test >>= 1) > 0;)
249: b--;
250: matched_off = cp - v;
251: b += matched_off << 3;
252: rn_b = -1 - b;
253: /*
254: * If there is a host route in a duped-key chain, it will be first.
255: */
256: if ((saved_t = t)->rn_mask == 0)
257: t = t->rn_dupedkey;
258: for (; t; t = t->rn_dupedkey)
259: /*
260: * Even if we don't match exactly as a host,
261: * we may match if the leaf we wound up at is
262: * a route to a net.
263: */
264: if (t->rn_flags & RNF_NORMAL) {
265: if (rn_b <= t->rn_b)
266: return t;
267: } else if (rn_satisfies_leaf(v, t, matched_off))
268: return t;
269: t = saved_t;
270: /* start searching up the tree */
271: do {
272: struct radix_mask *m;
273: t = t->rn_p;
274: m = t->rn_mklist;
275: if (m) {
276: /*
277: * If non-contiguous masks ever become important
278: * we can restore the masking and open coding of
279: * the search and satisfaction test and put the
280: * calculation of "off" back before the "do".
281: */
282: do {
283: if (m->rm_flags & RNF_NORMAL) {
284: if (rn_b <= m->rm_b)
285: return (m->rm_leaf);
286: } else {
287: off = min(t->rn_off, matched_off);
288: x = rn_search_m(v, t, m->rm_mask);
289: while (x && x->rn_mask != m->rm_mask)
290: x = x->rn_dupedkey;
291: if (x && rn_satisfies_leaf(v, x, off))
292: return x;
293: }
294: m = m->rm_mklist;
295: } while (m);
296: }
297: } while (t != top);
298: return 0;
299: }
300:
301: #ifdef RN_DEBUG
302: int rn_nodenum;
303: struct radix_node *rn_clist;
304: int rn_saveinfo;
305: int rn_debug = 1;
306: #endif
307:
308: struct radix_node *
309: rn_newpair(void *v, int b, struct radix_node nodes[2])
310: {
311: struct radix_node *tt = nodes, *t = tt + 1;
312: t->rn_b = b;
313: t->rn_bmask = 0x80 >> (b & 7);
314: t->rn_l = tt;
315: t->rn_off = b >> 3;
316: tt->rn_b = -1;
317: tt->rn_key = (caddr_t)v;
318: tt->rn_p = t;
319: tt->rn_flags = t->rn_flags = RNF_ACTIVE;
320: #ifdef RN_DEBUG
321: tt->rn_info = rn_nodenum++;
322: t->rn_info = rn_nodenum++;
323: tt->rn_twin = t;
324: tt->rn_ybro = rn_clist;
325: rn_clist = tt;
326: #endif
327: return t;
328: }
329:
330: struct radix_node *
331: rn_insert(void *v_arg, struct radix_node_head *head,
332: int *dupentry, struct radix_node nodes[2])
333: {
334: caddr_t v = v_arg;
335: struct radix_node *top = head->rnh_treetop;
336: int head_off = top->rn_off, vlen = (int)*((u_char *)v);
337: struct radix_node *t = rn_search(v_arg, top);
338: caddr_t cp = v + head_off;
339: int b;
340: struct radix_node *tt;
341: /*
342: * Find first bit at which v and t->rn_key differ
343: */
344: {
345: caddr_t cp2 = t->rn_key + head_off;
346: int cmp_res;
347: caddr_t cplim = v + vlen;
348:
349: while (cp < cplim)
350: if (*cp2++ != *cp++)
351: goto on1;
352: *dupentry = 1;
353: return t;
354: on1:
355: *dupentry = 0;
356: cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
357: for (b = (cp - v) << 3; cmp_res; b--)
358: cmp_res >>= 1;
359: }
360: {
361: struct radix_node *p, *x = top;
362: cp = v;
363: do {
364: p = x;
365: if (cp[x->rn_off] & x->rn_bmask)
366: x = x->rn_r;
367: else
368: x = x->rn_l;
369: } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */
370: #ifdef RN_DEBUG
371: if (rn_debug)
372: log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
373: #endif
374: t = rn_newpair(v_arg, b, nodes);
375: tt = t->rn_l;
376: if ((cp[p->rn_off] & p->rn_bmask) == 0)
377: p->rn_l = t;
378: else
379: p->rn_r = t;
380: x->rn_p = t;
381: t->rn_p = p; /* frees x, p as temp vars below */
382: if ((cp[t->rn_off] & t->rn_bmask) == 0) {
383: t->rn_r = x;
384: } else {
385: t->rn_r = tt;
386: t->rn_l = x;
387: }
388: #ifdef RN_DEBUG
389: if (rn_debug)
390: log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
391: #endif
392: }
393: return (tt);
394: }
395:
396: struct radix_node *
397: rn_addmask(void *n_arg, int search, int skip)
398: {
399: caddr_t netmask = (caddr_t)n_arg;
400: struct radix_node *x;
401: caddr_t cp, cplim;
402: int b = 0, mlen, j;
403: int maskduplicated, m0, isnormal;
404: struct radix_node *saved_x;
405: static int last_zeroed = 0;
406:
407: if ((mlen = *(u_char *)netmask) > max_keylen)
408: mlen = max_keylen;
409: if (skip == 0)
410: skip = 1;
411: if (mlen <= skip)
412: return (mask_rnhead->rnh_nodes);
413: if (skip > 1)
414: Bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
415: if ((m0 = mlen) > skip)
416: Bcopy(netmask + skip, addmask_key + skip, mlen - skip);
417: /*
418: * Trim trailing zeroes.
419: */
420: for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
421: cp--;
422: mlen = cp - addmask_key;
423: if (mlen <= skip) {
424: if (m0 >= last_zeroed)
425: last_zeroed = mlen;
426: return (mask_rnhead->rnh_nodes);
427: }
428: if (m0 < last_zeroed)
429: Bzero(addmask_key + m0, last_zeroed - m0);
430: *addmask_key = last_zeroed = mlen;
431: x = rn_search(addmask_key, rn_masktop);
432: if (Bcmp(addmask_key, x->rn_key, mlen) != 0)
433: x = 0;
434: if (x || search)
435: return (x);
436: R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x));
437: if ((saved_x = x) == 0)
438: return (0);
439: Bzero(x, max_keylen + 2 * sizeof (*x));
440: netmask = cp = (caddr_t)(x + 2);
441: Bcopy(addmask_key, cp, mlen);
442: x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
443: if (maskduplicated) {
444: log(LOG_ERR, "rn_addmask: mask impossibly already in tree\n");
445: Free(saved_x);
446: return (x);
447: }
448: /*
449: * Calculate index of mask, and check for normalcy.
450: */
451: cplim = netmask + mlen;
452: isnormal = 1;
453: for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;)
454: cp++;
455: if (cp != cplim) {
456: for (j = 0x80; (j & *cp) != 0; j >>= 1)
457: b++;
458: if (*cp != normal_chars[b] || cp != (cplim - 1))
459: isnormal = 0;
460: }
461: b += (cp - netmask) << 3;
462: x->rn_b = -1 - b;
463: if (isnormal)
464: x->rn_flags |= RNF_NORMAL;
465: return (x);
466: }
467:
468: static int /* XXX: arbitrary ordering for non-contiguous masks */
469: rn_lexobetter(void *m_arg, void *n_arg)
470: {
471: u_char *mp = m_arg, *np = n_arg, *lim;
472:
473: if (*mp > *np)
474: return 1; /* not really, but need to check longer one first */
475: if (*mp == *np)
476: for (lim = mp + *mp; mp < lim;)
477: if (*mp++ > *np++)
478: return 1;
479: return 0;
480: }
481:
482: static struct radix_mask *
483: rn_new_radix_mask(struct radix_node *tt, struct radix_mask *next)
484: {
485: struct radix_mask *m;
486:
487: MKGet(m);
488: if (m == 0) {
489: log(LOG_ERR, "Mask for route not entered\n");
490: return (0);
491: }
492: Bzero(m, sizeof *m);
493: m->rm_b = tt->rn_b;
494: m->rm_flags = tt->rn_flags;
495: if (tt->rn_flags & RNF_NORMAL)
496: m->rm_leaf = tt;
497: else
498: m->rm_mask = tt->rn_mask;
499: m->rm_mklist = next;
500: tt->rn_mklist = m;
501: return m;
502: }
503:
504: struct radix_node *
505: rn_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
506: struct radix_node treenodes[2])
507: {
508: caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg;
509: struct radix_node *t, *x = NULL, *tt;
510: struct radix_node *saved_tt, *top = head->rnh_treetop;
511: short b = 0, b_leaf = 0;
512: int keyduplicated;
513: caddr_t mmask;
514: struct radix_mask *m, **mp;
515:
516: /*
517: * In dealing with non-contiguous masks, there may be
518: * many different routes which have the same mask.
519: * We will find it useful to have a unique pointer to
520: * the mask to speed avoiding duplicate references at
521: * nodes and possibly save time in calculating indices.
522: */
523: if (netmask) {
524: if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0)
525: return (0);
526: b_leaf = x->rn_b;
527: b = -1 - x->rn_b;
528: netmask = x->rn_key;
529: }
530: /*
531: * Deal with duplicated keys: attach node to previous instance
532: */
533: saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes);
534: if (keyduplicated) {
535: for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
536: #ifndef SMALL_KERNEL
537: /* permit multipath, if enabled for the family */
538: if (rn_mpath_capable(head) && netmask == tt->rn_mask) {
539: /*
540: * Try to insert the new node in the middle
541: * of the list of any preexisting multipaths,
542: * to reduce the number of path disruptions
543: * that occur as a result of an insertion,
544: * per RFC2992.
545: */
546: int mid = rn_mpath_count(tt) / 2;
547: do {
548: t = tt;
549: tt = tt->rn_dupedkey;
550: } while (tt && t->rn_mask == tt->rn_mask
551: && --mid > 0);
552: break;
553: }
554: #endif
555: if (tt->rn_mask == netmask)
556: return (0);
557: if (netmask == 0 ||
558: (tt->rn_mask &&
559: ((b_leaf < tt->rn_b) || /* index(netmask) > node */
560: rn_refines(netmask, tt->rn_mask) ||
561: rn_lexobetter(netmask, tt->rn_mask))))
562: break;
563: }
564: /*
565: * If the mask is not duplicated, we wouldn't
566: * find it among possible duplicate key entries
567: * anyway, so the above test doesn't hurt.
568: *
569: * We sort the masks for a duplicated key the same way as
570: * in a masklist -- most specific to least specific.
571: * This may require the unfortunate nuisance of relocating
572: * the head of the list.
573: *
574: * We also reverse, or doubly link the list through the
575: * parent pointer.
576: */
577: if (tt == saved_tt) {
578: struct radix_node *xx = x;
579: /* link in at head of list */
580: (tt = treenodes)->rn_dupedkey = t;
581: tt->rn_flags = t->rn_flags;
582: tt->rn_p = x = t->rn_p;
583: t->rn_p = tt;
584: if (x->rn_l == t)
585: x->rn_l = tt;
586: else
587: x->rn_r = tt;
588: saved_tt = tt;
589: x = xx;
590: } else {
591: (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
592: t->rn_dupedkey = tt;
593: tt->rn_p = t;
594: if (tt->rn_dupedkey)
595: tt->rn_dupedkey->rn_p = tt;
596: }
597: #ifdef RN_DEBUG
598: t=tt+1;
599: tt->rn_info = rn_nodenum++;
600: t->rn_info = rn_nodenum++;
601: tt->rn_twin = t;
602: tt->rn_ybro = rn_clist;
603: rn_clist = tt;
604: #endif
605: tt->rn_key = (caddr_t) v;
606: tt->rn_b = -1;
607: tt->rn_flags = RNF_ACTIVE;
608: }
609: /*
610: * Put mask in tree.
611: */
612: if (netmask) {
613: tt->rn_mask = netmask;
614: tt->rn_b = x->rn_b;
615: tt->rn_flags |= x->rn_flags & RNF_NORMAL;
616: }
617: t = saved_tt->rn_p;
618: if (keyduplicated)
619: goto on2;
620: b_leaf = -1 - t->rn_b;
621: if (t->rn_r == saved_tt)
622: x = t->rn_l;
623: else
624: x = t->rn_r;
625: /* Promote general routes from below */
626: if (x->rn_b < 0) {
627: for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
628: if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) {
629: *mp = m = rn_new_radix_mask(x, 0);
630: if (m)
631: mp = &m->rm_mklist;
632: }
633: } else if (x->rn_mklist) {
634: /*
635: * Skip over masks whose index is > that of new node
636: */
637: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
638: if (m->rm_b >= b_leaf)
639: break;
640: t->rn_mklist = m;
641: *mp = 0;
642: }
643: on2:
644: /* Add new route to highest possible ancestor's list */
645: if ((netmask == 0) || (b > t->rn_b ))
646: return tt; /* can't lift at all */
647: b_leaf = tt->rn_b;
648: do {
649: x = t;
650: t = t->rn_p;
651: } while (b <= t->rn_b && x != top);
652: /*
653: * Search through routes associated with node to
654: * insert new route according to index.
655: * Need same criteria as when sorting dupedkeys to avoid
656: * double loop on deletion.
657: */
658: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
659: if (m->rm_b < b_leaf)
660: continue;
661: if (m->rm_b > b_leaf)
662: break;
663: if (m->rm_flags & RNF_NORMAL) {
664: mmask = m->rm_leaf->rn_mask;
665: if (tt->rn_flags & RNF_NORMAL) {
666: log(LOG_ERR, "Non-unique normal route,"
667: " mask not entered\n");
668: return tt;
669: }
670: } else
671: mmask = m->rm_mask;
672: if (mmask == netmask) {
673: m->rm_refs++;
674: tt->rn_mklist = m;
675: return tt;
676: }
677: if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask))
678: break;
679: }
680: *mp = rn_new_radix_mask(tt, *mp);
681: return tt;
682: }
683:
684: struct radix_node *
685: rn_delete(void *v_arg, void *netmask_arg, struct radix_node_head *head,
686: struct radix_node *rn)
687: {
688: struct radix_node *t, *p, *x, *tt;
689: struct radix_mask *m, *saved_m, **mp;
690: struct radix_node *dupedkey, *saved_tt, *top;
691: caddr_t v, netmask;
692: int b, head_off, vlen;
693: #ifndef SMALL_KERNEL
694: int mpath_enable = 0;
695: #endif
696:
697: v = v_arg;
698: netmask = netmask_arg;
699: x = head->rnh_treetop;
700: #ifndef SMALL_KERNEL
701: if (rn) {
702: tt = rn;
703: /*
704: * Is this route(rn) a rn->dupedkey chain?
705: */
706: if (rn_mpath_next(tt->rn_p))
707: mpath_enable = 1;
708: else
709: tt = rn_search(v, x);
710: } else
711: tt = rn_search(v, x);
712: #else
713: tt = rn_search(v, x);
714: #endif
715: head_off = x->rn_off;
716: vlen = *(u_char *)v;
717: saved_tt = tt;
718: top = x;
719: if (tt == 0 ||
720: Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
721: return (0);
722: /*
723: * Delete our route from mask lists.
724: */
725: if (netmask) {
726: if ((x = rn_addmask(netmask, 1, head_off)) == 0)
727: return (0);
728: netmask = x->rn_key;
729: while (tt->rn_mask != netmask)
730: if ((tt = tt->rn_dupedkey) == 0)
731: return (0);
732: }
733: if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0)
734: goto on1;
735: if (tt->rn_flags & RNF_NORMAL) {
736: if (m->rm_leaf != tt || m->rm_refs > 0) {
737: log(LOG_ERR, "rn_delete: inconsistent annotation\n");
738: return 0; /* dangling ref could cause disaster */
739: }
740: } else {
741: if (m->rm_mask != tt->rn_mask) {
742: log(LOG_ERR, "rn_delete: inconsistent annotation\n");
743: goto on1;
744: }
745: if (--m->rm_refs >= 0)
746: goto on1;
747: }
748: b = -1 - tt->rn_b;
749: t = saved_tt->rn_p;
750: if (b > t->rn_b)
751: goto on1; /* Wasn't lifted at all */
752: do {
753: x = t;
754: t = t->rn_p;
755: } while (b <= t->rn_b && x != top);
756: for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
757: if (m == saved_m) {
758: *mp = m->rm_mklist;
759: MKFree(m);
760: break;
761: }
762: if (m == 0) {
763: log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
764: if (tt->rn_flags & RNF_NORMAL)
765: return (0); /* Dangling ref to us */
766: }
767: on1:
768: /*
769: * Eliminate us from tree
770: */
771: if (tt->rn_flags & RNF_ROOT)
772: return (0);
773: #ifdef RN_DEBUG
774: /* Get us out of the creation list */
775: for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro)
776: ;
777: if (t) t->rn_ybro = tt->rn_ybro;
778: #endif
779: t = tt->rn_p;
780: dupedkey = saved_tt->rn_dupedkey;
781: if (dupedkey) {
782: /*
783: * Here, tt is the deletion target, and
784: * saved_tt is the head of the dupedkey chain.
785: */
786: if (tt == saved_tt) {
787: x = dupedkey;
788: x->rn_p = t;
789: if (t->rn_l == tt)
790: t->rn_l = x;
791: else
792: t->rn_r = x;
793: } else {
794: /* find node in front of tt on the chain */
795: for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
796: p = p->rn_dupedkey;
797: if (p) {
798: p->rn_dupedkey = tt->rn_dupedkey;
799: if (tt->rn_dupedkey)
800: tt->rn_dupedkey->rn_p = p;
801: } else log(LOG_ERR, "rn_delete: couldn't find us\n");
802: }
803: t = tt + 1;
804: if (t->rn_flags & RNF_ACTIVE) {
805: #ifndef RN_DEBUG
806: *++x = *t;
807: p = t->rn_p;
808: #else
809: b = t->rn_info;
810: *++x = *t;
811: t->rn_info = b;
812: p = t->rn_p;
813: #endif
814: if (p->rn_l == t)
815: p->rn_l = x;
816: else
817: p->rn_r = x;
818: x->rn_l->rn_p = x;
819: x->rn_r->rn_p = x;
820: }
821: goto out;
822: }
823: #ifndef SMALL_KERNEL
824: if (mpath_enable) {
825: /*
826: * my parent dupedkey is NULL
827: * end of mpath route.
828: */
829: t->rn_dupedkey = NULL;
830: goto out;
831: }
832: #endif
833: if (t->rn_l == tt)
834: x = t->rn_r;
835: else
836: x = t->rn_l;
837: p = t->rn_p;
838: if (p->rn_r == t)
839: p->rn_r = x;
840: else
841: p->rn_l = x;
842: x->rn_p = p;
843: /*
844: * Demote routes attached to us.
845: */
846: if (t->rn_mklist) {
847: if (x->rn_b >= 0) {
848: for (mp = &x->rn_mklist; (m = *mp);)
849: mp = &m->rm_mklist;
850: *mp = t->rn_mklist;
851: } else {
852: /* If there are any key,mask pairs in a sibling
853: duped-key chain, some subset will appear sorted
854: in the same order attached to our mklist */
855: for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
856: if (m == x->rn_mklist) {
857: struct radix_mask *mm = m->rm_mklist;
858: x->rn_mklist = 0;
859: if (--(m->rm_refs) < 0)
860: MKFree(m);
861: m = mm;
862: }
863: if (m)
864: log(LOG_ERR, "%s %p at %p\n",
865: "rn_delete: Orphaned Mask", m, x);
866: }
867: }
868: /*
869: * We may be holding an active internal node in the tree.
870: */
871: x = tt + 1;
872: if (t != x) {
873: #ifndef RN_DEBUG
874: *t = *x;
875: #else
876: b = t->rn_info;
877: *t = *x;
878: t->rn_info = b;
879: #endif
880: t->rn_l->rn_p = t;
881: t->rn_r->rn_p = t;
882: p = x->rn_p;
883: if (p->rn_l == x)
884: p->rn_l = t;
885: else
886: p->rn_r = t;
887: }
888: out:
889: tt->rn_flags &= ~RNF_ACTIVE;
890: tt[1].rn_flags &= ~RNF_ACTIVE;
891: return (tt);
892: }
893:
894: int
895: rn_walktree(struct radix_node_head *h, int (*f)(struct radix_node *, void *),
896: void *w)
897: {
898: int error;
899: struct radix_node *base, *next;
900: struct radix_node *rn = h->rnh_treetop;
901: /*
902: * This gets complicated because we may delete the node
903: * while applying the function f to it, so we need to calculate
904: * the successor node in advance.
905: */
906: /* First time through node, go left */
907: while (rn->rn_b >= 0)
908: rn = rn->rn_l;
909: for (;;) {
910: base = rn;
911: /* If at right child go back up, otherwise, go right */
912: while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0)
913: rn = rn->rn_p;
914: /* Find the next *leaf* since next node might vanish, too */
915: for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;)
916: rn = rn->rn_l;
917: next = rn;
918: /* Process leaves */
919: while ((rn = base) != NULL) {
920: base = rn->rn_dupedkey;
921: if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w)))
922: return (error);
923: }
924: rn = next;
925: if (rn->rn_flags & RNF_ROOT)
926: return (0);
927: }
928: /* NOTREACHED */
929: }
930:
931: int
932: rn_inithead(void **head, int off)
933: {
934: struct radix_node_head *rnh;
935:
936: if (*head)
937: return (1);
938: R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh));
939: if (rnh == 0)
940: return (0);
941: *head = rnh;
942: return rn_inithead0(rnh, off);
943: }
944:
945: int
946: rn_inithead0(struct radix_node_head *rnh, int off)
947: {
948: struct radix_node *t, *tt, *ttt;
949:
950: Bzero(rnh, sizeof (*rnh));
951: t = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
952: ttt = rnh->rnh_nodes + 2;
953: t->rn_r = ttt;
954: t->rn_p = t;
955: tt = t->rn_l;
956: tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
957: tt->rn_b = -1 - off;
958: *ttt = *tt;
959: ttt->rn_key = rn_ones;
960: rnh->rnh_addaddr = rn_addroute;
961: rnh->rnh_deladdr = rn_delete;
962: rnh->rnh_matchaddr = rn_match;
963: rnh->rnh_lookup = rn_lookup;
964: rnh->rnh_walktree = rn_walktree;
965: rnh->rnh_treetop = t;
966: return (1);
967: }
968:
969: void
970: rn_init()
971: {
972: char *cp, *cplim;
973: #ifdef _KERNEL
974: struct domain *dom;
975:
976: for (dom = domains; dom; dom = dom->dom_next)
977: if (dom->dom_maxrtkey > max_keylen)
978: max_keylen = dom->dom_maxrtkey;
979: #endif
980: if (max_keylen == 0) {
981: log(LOG_ERR,
982: "rn_init: radix functions require max_keylen be set\n");
983: return;
984: }
985: R_Malloc(rn_zeros, char *, 3 * max_keylen);
986: if (rn_zeros == NULL)
987: panic("rn_init");
988: Bzero(rn_zeros, 3 * max_keylen);
989: rn_ones = cp = rn_zeros + max_keylen;
990: addmask_key = cplim = rn_ones + max_keylen;
991: while (cp < cplim)
992: *cp++ = -1;
993: if (rn_inithead((void *)&mask_rnhead, 0) == 0)
994: panic("rn_init 2");
995: }
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