radix.c revision 12579
1/* 2 * Copyright (c) 1988, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)radix.c 8.4 (Berkeley) 11/2/94 34 * $Id: radix.c,v 1.9 1995/05/30 08:08:20 rgrimes Exp $ 35 */ 36 37/* 38 * Routines to build and maintain radix trees for routing lookups. 39 */ 40#ifndef _RADIX_H_ 41#include <sys/param.h> 42#ifdef KERNEL 43#include <sys/systm.h> 44#include <sys/malloc.h> 45#define M_DONTWAIT M_NOWAIT 46#include <sys/domain.h> 47#else 48#include <stdlib.h> 49#endif 50#include <sys/syslog.h> 51#include <net/radix.h> 52#endif 53 54extern struct radix_node * 55 rn_lookup __P((void *v_arg, void *m_arg, 56 struct radix_node_head *head)); 57extern int rn_walktree_from __P((struct radix_node_head *h, void *a, 58 void *m, walktree_f_t *f, void *w)); 59 60int max_keylen; 61struct radix_mask *rn_mkfreelist; 62struct radix_node_head *mask_rnhead; 63static char *addmask_key; 64static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 65static char *rn_zeros, *rn_ones; 66 67#define rn_masktop (mask_rnhead->rnh_treetop) 68#undef Bcmp 69#define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 70 71static int rn_lexobetter __P((void *m_arg, void *n_arg)); 72static struct radix_mask * 73 rn_new_radix_mask __P((struct radix_node *tt, 74 struct radix_mask *next)); 75static int rn_satsifies_leaf __P((char *trial, struct radix_node *leaf, 76 int skip)); 77 78/* 79 * The data structure for the keys is a radix tree with one way 80 * branching removed. The index rn_b at an internal node n represents a bit 81 * position to be tested. The tree is arranged so that all descendants 82 * of a node n have keys whose bits all agree up to position rn_b - 1. 83 * (We say the index of n is rn_b.) 84 * 85 * There is at least one descendant which has a one bit at position rn_b, 86 * and at least one with a zero there. 87 * 88 * A route is determined by a pair of key and mask. We require that the 89 * bit-wise logical and of the key and mask to be the key. 90 * We define the index of a route to associated with the mask to be 91 * the first bit number in the mask where 0 occurs (with bit number 0 92 * representing the highest order bit). 93 * 94 * We say a mask is normal if every bit is 0, past the index of the mask. 95 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 96 * and m is a normal mask, then the route applies to every descendant of n. 97 * If the index(m) < rn_b, this implies the trailing last few bits of k 98 * before bit b are all 0, (and hence consequently true of every descendant 99 * of n), so the route applies to all descendants of the node as well. 100 * 101 * Similar logic shows that a non-normal mask m such that 102 * index(m) <= index(n) could potentially apply to many children of n. 103 * Thus, for each non-host route, we attach its mask to a list at an internal 104 * node as high in the tree as we can go. 105 * 106 * The present version of the code makes use of normal routes in short- 107 * circuiting an explict mask and compare operation when testing whether 108 * a key satisfies a normal route, and also in remembering the unique leaf 109 * that governs a subtree. 110 */ 111 112struct radix_node * 113rn_search(v_arg, head) 114 void *v_arg; 115 struct radix_node *head; 116{ 117 register struct radix_node *x; 118 register caddr_t v; 119 120 for (x = head, v = v_arg; x->rn_b >= 0;) { 121 if (x->rn_bmask & v[x->rn_off]) 122 x = x->rn_r; 123 else 124 x = x->rn_l; 125 } 126 return (x); 127}; 128 129struct radix_node * 130rn_search_m(v_arg, head, m_arg) 131 struct radix_node *head; 132 void *v_arg, *m_arg; 133{ 134 register struct radix_node *x; 135 register caddr_t v = v_arg, m = m_arg; 136 137 for (x = head; x->rn_b >= 0;) { 138 if ((x->rn_bmask & m[x->rn_off]) && 139 (x->rn_bmask & v[x->rn_off])) 140 x = x->rn_r; 141 else 142 x = x->rn_l; 143 } 144 return x; 145}; 146 147int 148rn_refines(m_arg, n_arg) 149 void *m_arg, *n_arg; 150{ 151 register caddr_t m = m_arg, n = n_arg; 152 register caddr_t lim, lim2 = lim = n + *(u_char *)n; 153 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 154 int masks_are_equal = 1; 155 156 if (longer > 0) 157 lim -= longer; 158 while (n < lim) { 159 if (*n & ~(*m)) 160 return 0; 161 if (*n++ != *m++) 162 masks_are_equal = 0; 163 } 164 while (n < lim2) 165 if (*n++) 166 return 0; 167 if (masks_are_equal && (longer < 0)) 168 for (lim2 = m - longer; m < lim2; ) 169 if (*m++) 170 return 1; 171 return (!masks_are_equal); 172} 173 174struct radix_node * 175rn_lookup(v_arg, m_arg, head) 176 void *v_arg, *m_arg; 177 struct radix_node_head *head; 178{ 179 register struct radix_node *x; 180 caddr_t netmask = 0; 181 182 if (m_arg) { 183 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 184 return (0); 185 netmask = x->rn_key; 186 } 187 x = rn_match(v_arg, head); 188 if (x && netmask) { 189 while (x && x->rn_mask != netmask) 190 x = x->rn_dupedkey; 191 } 192 return x; 193} 194 195static int 196rn_satsifies_leaf(trial, leaf, skip) 197 char *trial; 198 register struct radix_node *leaf; 199 int skip; 200{ 201 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 202 char *cplim; 203 int length = min(*(u_char *)cp, *(u_char *)cp2); 204 205 if (cp3 == 0) 206 cp3 = rn_ones; 207 else 208 length = min(length, *(u_char *)cp3); 209 cplim = cp + length; cp3 += skip; cp2 += skip; 210 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 211 if ((*cp ^ *cp2) & *cp3) 212 return 0; 213 return 1; 214} 215 216struct radix_node * 217rn_match(v_arg, head) 218 void *v_arg; 219 struct radix_node_head *head; 220{ 221 caddr_t v = v_arg; 222 register struct radix_node *t = head->rnh_treetop, *x; 223 register caddr_t cp = v, cp2; 224 caddr_t cplim; 225 struct radix_node *saved_t, *top = t; 226 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 227 register int test, b, rn_b; 228 229 /* 230 * Open code rn_search(v, top) to avoid overhead of extra 231 * subroutine call. 232 */ 233 for (; t->rn_b >= 0; ) { 234 if (t->rn_bmask & cp[t->rn_off]) 235 t = t->rn_r; 236 else 237 t = t->rn_l; 238 } 239 /* 240 * See if we match exactly as a host destination 241 * or at least learn how many bits match, for normal mask finesse. 242 * 243 * It doesn't hurt us to limit how many bytes to check 244 * to the length of the mask, since if it matches we had a genuine 245 * match and the leaf we have is the most specific one anyway; 246 * if it didn't match with a shorter length it would fail 247 * with a long one. This wins big for class B&C netmasks which 248 * are probably the most common case... 249 */ 250 if (t->rn_mask) 251 vlen = *(u_char *)t->rn_mask; 252 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 253 for (; cp < cplim; cp++, cp2++) 254 if (*cp != *cp2) 255 goto on1; 256 /* 257 * This extra grot is in case we are explicitly asked 258 * to look up the default. Ugh! 259 */ 260 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 261 t = t->rn_dupedkey; 262 return t; 263on1: 264 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 265 for (b = 7; (test >>= 1) > 0;) 266 b--; 267 matched_off = cp - v; 268 b += matched_off << 3; 269 rn_b = -1 - b; 270 /* 271 * If there is a host route in a duped-key chain, it will be first. 272 */ 273 if ((saved_t = t)->rn_mask == 0) 274 t = t->rn_dupedkey; 275 for (; t; t = t->rn_dupedkey) 276 /* 277 * Even if we don't match exactly as a host, 278 * we may match if the leaf we wound up at is 279 * a route to a net. 280 */ 281 if (t->rn_flags & RNF_NORMAL) { 282 if (rn_b <= t->rn_b) 283 return t; 284 } else if (rn_satsifies_leaf(v, t, matched_off)) 285 return t; 286 t = saved_t; 287 /* start searching up the tree */ 288 do { 289 register struct radix_mask *m; 290 t = t->rn_p; 291 m = t->rn_mklist; 292 if (m) { 293 /* 294 * If non-contiguous masks ever become important 295 * we can restore the masking and open coding of 296 * the search and satisfaction test and put the 297 * calculation of "off" back before the "do". 298 */ 299 do { 300 if (m->rm_flags & RNF_NORMAL) { 301 if (rn_b <= m->rm_b) 302 return (m->rm_leaf); 303 } else { 304 off = min(t->rn_off, matched_off); 305 x = rn_search_m(v, t, m->rm_mask); 306 while (x && x->rn_mask != m->rm_mask) 307 x = x->rn_dupedkey; 308 if (x && rn_satsifies_leaf(v, x, off)) 309 return x; 310 } 311 m = m->rm_mklist; 312 } while (m); 313 } 314 } while (t != top); 315 return 0; 316}; 317 318#ifdef RN_DEBUG 319int rn_nodenum; 320struct radix_node *rn_clist; 321int rn_saveinfo; 322int rn_debug = 1; 323#endif 324 325struct radix_node * 326rn_newpair(v, b, nodes) 327 void *v; 328 int b; 329 struct radix_node nodes[2]; 330{ 331 register struct radix_node *tt = nodes, *t = tt + 1; 332 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 333 t->rn_l = tt; t->rn_off = b >> 3; 334 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 335 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 336#ifdef RN_DEBUG 337 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 338 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 339#endif 340 return t; 341} 342 343struct radix_node * 344rn_insert(v_arg, head, dupentry, nodes) 345 void *v_arg; 346 struct radix_node_head *head; 347 int *dupentry; 348 struct radix_node nodes[2]; 349{ 350 caddr_t v = v_arg; 351 struct radix_node *top = head->rnh_treetop; 352 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 353 register struct radix_node *t = rn_search(v_arg, top); 354 register caddr_t cp = v + head_off; 355 register int b; 356 struct radix_node *tt; 357 /* 358 * Find first bit at which v and t->rn_key differ 359 */ 360 { 361 register caddr_t cp2 = t->rn_key + head_off; 362 register int cmp_res; 363 caddr_t cplim = v + vlen; 364 365 while (cp < cplim) 366 if (*cp2++ != *cp++) 367 goto on1; 368 *dupentry = 1; 369 return t; 370on1: 371 *dupentry = 0; 372 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 373 for (b = (cp - v) << 3; cmp_res; b--) 374 cmp_res >>= 1; 375 } 376 { 377 register struct radix_node *p, *x = top; 378 cp = v; 379 do { 380 p = x; 381 if (cp[x->rn_off] & x->rn_bmask) 382 x = x->rn_r; 383 else x = x->rn_l; 384 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 385#ifdef RN_DEBUG 386 if (rn_debug) 387 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 388#endif 389 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 390 if ((cp[p->rn_off] & p->rn_bmask) == 0) 391 p->rn_l = t; 392 else 393 p->rn_r = t; 394 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 395 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 396 t->rn_r = x; 397 } else { 398 t->rn_r = tt; t->rn_l = x; 399 } 400#ifdef RN_DEBUG 401 if (rn_debug) 402 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 403#endif 404 } 405 return (tt); 406} 407 408struct radix_node * 409rn_addmask(n_arg, search, skip) 410 int search, skip; 411 void *n_arg; 412{ 413 caddr_t netmask = (caddr_t)n_arg; 414 register struct radix_node *x; 415 register caddr_t cp, cplim; 416 register int b = 0, mlen, j; 417 int maskduplicated, m0, isnormal; 418 struct radix_node *saved_x; 419 static int last_zeroed = 0; 420 421 if ((mlen = *(u_char *)netmask) > max_keylen) 422 mlen = max_keylen; 423 if (skip == 0) 424 skip = 1; 425 if (mlen <= skip) 426 return (mask_rnhead->rnh_nodes); 427 if (skip > 1) 428 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 429 if ((m0 = mlen) > skip) 430 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 431 /* 432 * Trim trailing zeroes. 433 */ 434 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 435 cp--; 436 mlen = cp - addmask_key; 437 if (mlen <= skip) { 438 if (m0 >= last_zeroed) 439 last_zeroed = mlen; 440 return (mask_rnhead->rnh_nodes); 441 } 442 if (m0 < last_zeroed) 443 Bzero(addmask_key + m0, last_zeroed - m0); 444 *addmask_key = last_zeroed = mlen; 445 x = rn_search(addmask_key, rn_masktop); 446 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 447 x = 0; 448 if (x || search) 449 return (x); 450 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 451 if ((saved_x = x) == 0) 452 return (0); 453 Bzero(x, max_keylen + 2 * sizeof (*x)); 454 netmask = cp = (caddr_t)(x + 2); 455 Bcopy(addmask_key, cp, mlen); 456 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 457 if (maskduplicated) { 458 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 459 Free(saved_x); 460 return (x); 461 } 462 /* 463 * Calculate index of mask, and check for normalcy. 464 */ 465 cplim = netmask + mlen; isnormal = 1; 466 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 467 cp++; 468 if (cp != cplim) { 469 for (j = 0x80; (j & *cp) != 0; j >>= 1) 470 b++; 471 if (*cp != normal_chars[b] || cp != (cplim - 1)) 472 isnormal = 0; 473 } 474 b += (cp - netmask) << 3; 475 x->rn_b = -1 - b; 476 if (isnormal) 477 x->rn_flags |= RNF_NORMAL; 478 return (x); 479} 480 481static int /* XXX: arbitrary ordering for non-contiguous masks */ 482rn_lexobetter(m_arg, n_arg) 483 void *m_arg, *n_arg; 484{ 485 register u_char *mp = m_arg, *np = n_arg, *lim; 486 487 if (*mp > *np) 488 return 1; /* not really, but need to check longer one first */ 489 if (*mp == *np) 490 for (lim = mp + *mp; mp < lim;) 491 if (*mp++ > *np++) 492 return 1; 493 return 0; 494} 495 496static struct radix_mask * 497rn_new_radix_mask(tt, next) 498 register struct radix_node *tt; 499 register struct radix_mask *next; 500{ 501 register struct radix_mask *m; 502 503 MKGet(m); 504 if (m == 0) { 505 log(LOG_ERR, "Mask for route not entered\n"); 506 return (0); 507 } 508 Bzero(m, sizeof *m); 509 m->rm_b = tt->rn_b; 510 m->rm_flags = tt->rn_flags; 511 if (tt->rn_flags & RNF_NORMAL) 512 m->rm_leaf = tt; 513 else 514 m->rm_mask = tt->rn_mask; 515 m->rm_mklist = next; 516 tt->rn_mklist = m; 517 return m; 518} 519 520struct radix_node * 521rn_addroute(v_arg, n_arg, head, treenodes) 522 void *v_arg, *n_arg; 523 struct radix_node_head *head; 524 struct radix_node treenodes[2]; 525{ 526 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 527 register struct radix_node *t, *x = 0, *tt; 528 struct radix_node *saved_tt, *top = head->rnh_treetop; 529 short b = 0, b_leaf = 0; 530 int keyduplicated; 531 caddr_t mmask; 532 struct radix_mask *m, **mp; 533 534 /* 535 * In dealing with non-contiguous masks, there may be 536 * many different routes which have the same mask. 537 * We will find it useful to have a unique pointer to 538 * the mask to speed avoiding duplicate references at 539 * nodes and possibly save time in calculating indices. 540 */ 541 if (netmask) { 542 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 543 return (0); 544 b_leaf = x->rn_b; 545 b = -1 - x->rn_b; 546 netmask = x->rn_key; 547 } 548 /* 549 * Deal with duplicated keys: attach node to previous instance 550 */ 551 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 552 if (keyduplicated) { 553 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 554 if (tt->rn_mask == netmask) 555 return (0); 556 if (netmask == 0 || 557 (tt->rn_mask && 558 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 559 rn_refines(netmask, tt->rn_mask) || 560 rn_lexobetter(netmask, tt->rn_mask)))) 561 break; 562 } 563 /* 564 * If the mask is not duplicated, we wouldn't 565 * find it among possible duplicate key entries 566 * anyway, so the above test doesn't hurt. 567 * 568 * We sort the masks for a duplicated key the same way as 569 * in a masklist -- most specific to least specific. 570 * This may require the unfortunate nuisance of relocating 571 * the head of the list. 572 */ 573 if (tt == saved_tt) { 574 struct radix_node *xx = x; 575 /* link in at head of list */ 576 (tt = treenodes)->rn_dupedkey = t; 577 tt->rn_flags = t->rn_flags; 578 tt->rn_p = x = t->rn_p; 579 t->rn_p = tt; /* parent */ 580 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 581 saved_tt = tt; x = xx; 582 } else { 583 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 584 t->rn_dupedkey = tt; 585 tt->rn_p = t; /* parent */ 586 if (tt->rn_dupedkey) /* parent */ 587 tt->rn_dupedkey->rn_p = tt; /* parent */ 588 } 589#ifdef RN_DEBUG 590 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 591 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 592#endif 593 tt->rn_key = (caddr_t) v; 594 tt->rn_b = -1; 595 tt->rn_flags = RNF_ACTIVE; 596 } 597 /* 598 * Put mask in tree. 599 */ 600 if (netmask) { 601 tt->rn_mask = netmask; 602 tt->rn_b = x->rn_b; 603 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 604 } 605 t = saved_tt->rn_p; 606 if (keyduplicated) 607 goto on2; 608 b_leaf = -1 - t->rn_b; 609 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 610 /* Promote general routes from below */ 611 if (x->rn_b < 0) { 612 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 613 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 614 *mp = m = rn_new_radix_mask(x, 0); 615 if (m) 616 mp = &m->rm_mklist; 617 } 618 } else if (x->rn_mklist) { 619 /* 620 * Skip over masks whose index is > that of new node 621 */ 622 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 623 if (m->rm_b >= b_leaf) 624 break; 625 t->rn_mklist = m; *mp = 0; 626 } 627on2: 628 /* Add new route to highest possible ancestor's list */ 629 if ((netmask == 0) || (b > t->rn_b )) 630 return tt; /* can't lift at all */ 631 b_leaf = tt->rn_b; 632 do { 633 x = t; 634 t = t->rn_p; 635 } while (b <= t->rn_b && x != top); 636 /* 637 * Search through routes associated with node to 638 * insert new route according to index. 639 * Need same criteria as when sorting dupedkeys to avoid 640 * double loop on deletion. 641 */ 642 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 643 if (m->rm_b < b_leaf) 644 continue; 645 if (m->rm_b > b_leaf) 646 break; 647 if (m->rm_flags & RNF_NORMAL) { 648 mmask = m->rm_leaf->rn_mask; 649 if (tt->rn_flags & RNF_NORMAL) { 650 log(LOG_ERR, 651 "Non-unique normal route, mask not entered"); 652 return tt; 653 } 654 } else 655 mmask = m->rm_mask; 656 if (mmask == netmask) { 657 m->rm_refs++; 658 tt->rn_mklist = m; 659 return tt; 660 } 661 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 662 break; 663 } 664 *mp = rn_new_radix_mask(tt, *mp); 665 return tt; 666} 667 668struct radix_node * 669rn_delete(v_arg, netmask_arg, head) 670 void *v_arg, *netmask_arg; 671 struct radix_node_head *head; 672{ 673 register struct radix_node *t, *p, *x, *tt; 674 struct radix_mask *m, *saved_m, **mp; 675 struct radix_node *dupedkey, *saved_tt, *top; 676 caddr_t v, netmask; 677 int b, head_off, vlen; 678 679 v = v_arg; 680 netmask = netmask_arg; 681 x = head->rnh_treetop; 682 tt = rn_search(v, x); 683 head_off = x->rn_off; 684 vlen = *(u_char *)v; 685 saved_tt = tt; 686 top = x; 687 if (tt == 0 || 688 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 689 return (0); 690 /* 691 * Delete our route from mask lists. 692 */ 693 if (netmask) { 694 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 695 return (0); 696 netmask = x->rn_key; 697 while (tt->rn_mask != netmask) 698 if ((tt = tt->rn_dupedkey) == 0) 699 return (0); 700 } 701 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 702 goto on1; 703 if (tt->rn_flags & RNF_NORMAL) { 704 if (m->rm_leaf != tt || m->rm_refs > 0) { 705 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 706 return 0; /* dangling ref could cause disaster */ 707 } 708 } else { 709 if (m->rm_mask != tt->rn_mask) { 710 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 711 goto on1; 712 } 713 if (--m->rm_refs >= 0) 714 goto on1; 715 } 716 b = -1 - tt->rn_b; 717 t = saved_tt->rn_p; 718 if (b > t->rn_b) 719 goto on1; /* Wasn't lifted at all */ 720 do { 721 x = t; 722 t = t->rn_p; 723 } while (b <= t->rn_b && x != top); 724 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 725 if (m == saved_m) { 726 *mp = m->rm_mklist; 727 MKFree(m); 728 break; 729 } 730 if (m == 0) { 731 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 732 if (tt->rn_flags & RNF_NORMAL) 733 return (0); /* Dangling ref to us */ 734 } 735on1: 736 /* 737 * Eliminate us from tree 738 */ 739 if (tt->rn_flags & RNF_ROOT) 740 return (0); 741#ifdef RN_DEBUG 742 /* Get us out of the creation list */ 743 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 744 if (t) t->rn_ybro = tt->rn_ybro; 745#endif 746 t = tt->rn_p; 747 dupedkey = saved_tt->rn_dupedkey; 748 if (dupedkey) { 749 /* 750 * at this point, tt is the deletion target and saved_tt 751 * is the head of the dupekey chain 752 */ 753 if (tt == saved_tt) { 754 /* remove from head of chain */ 755 x = dupedkey; x->rn_p = t; 756 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 757 } else { 758 /* find node in front of tt on the chain */ 759 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 760 p = p->rn_dupedkey; 761 if (p) { 762 p->rn_dupedkey = tt->rn_dupedkey; 763 if (tt->rn_dupedkey) /* parent */ 764 tt->rn_dupedkey->rn_p = p; /* parent */ 765 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 766 } 767 t = tt + 1; 768 if (t->rn_flags & RNF_ACTIVE) { 769#ifndef RN_DEBUG 770 *++x = *t; p = t->rn_p; 771#else 772 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 773#endif 774 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 775 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 776 } 777 goto out; 778 } 779 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 780 p = t->rn_p; 781 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 782 x->rn_p = p; 783 /* 784 * Demote routes attached to us. 785 */ 786 if (t->rn_mklist) { 787 if (x->rn_b >= 0) { 788 for (mp = &x->rn_mklist; (m = *mp);) 789 mp = &m->rm_mklist; 790 *mp = t->rn_mklist; 791 } else { 792 /* If there are any key,mask pairs in a sibling 793 duped-key chain, some subset will appear sorted 794 in the same order attached to our mklist */ 795 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 796 if (m == x->rn_mklist) { 797 struct radix_mask *mm = m->rm_mklist; 798 x->rn_mklist = 0; 799 if (--(m->rm_refs) < 0) 800 MKFree(m); 801 m = mm; 802 } 803 if (m) 804 log(LOG_ERR, "%s %p at %x\n", 805 "rn_delete: Orphaned Mask", m, x); 806 } 807 } 808 /* 809 * We may be holding an active internal node in the tree. 810 */ 811 x = tt + 1; 812 if (t != x) { 813#ifndef RN_DEBUG 814 *t = *x; 815#else 816 b = t->rn_info; *t = *x; t->rn_info = b; 817#endif 818 t->rn_l->rn_p = t; t->rn_r->rn_p = t; 819 p = x->rn_p; 820 if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; 821 } 822out: 823 tt->rn_flags &= ~RNF_ACTIVE; 824 tt[1].rn_flags &= ~RNF_ACTIVE; 825 return (tt); 826} 827 828/* 829 * This is the same as rn_walktree() except for the parameters and the 830 * exit. 831 */ 832int 833rn_walktree_from(h, a, m, f, w) 834 struct radix_node_head *h; 835 void *a, *m; 836 walktree_f_t *f; 837 void *w; 838{ 839 int error; 840 struct radix_node *base, *next; 841 u_char *xa = (u_char *)a; 842 u_char *xm = (u_char *)m; 843 register struct radix_node *rn, *last = 0 /* shut up gcc */; 844 int stopping = 0; 845 int lastb; 846 847 /* 848 * rn_search_m is sort-of-open-coded here. 849 */ 850 /* printf("about to search\n"); */ 851 for (rn = h->rnh_treetop; rn->rn_b >= 0; ) { 852 last = rn; 853 /* printf("rn_b %d, rn_bmask %x, xm[rn_off] %x\n", 854 rn->rn_b, rn->rn_bmask, xm[rn->rn_off]); */ 855 if (!(rn->rn_bmask & xm[rn->rn_off])) { 856 break; 857 } 858 if (rn->rn_bmask & xa[rn->rn_off]) { 859 rn = rn->rn_r; 860 } else { 861 rn = rn->rn_l; 862 } 863 } 864 /* printf("done searching\n"); */ 865 866 /* 867 * Two cases: either we stepped off the end of our mask, 868 * in which case last == rn, or we reached a leaf, in which 869 * case we want to start from the last node we looked at. 870 * Either way, last is the node we want to start from. 871 */ 872 rn = last; 873 lastb = rn->rn_b; 874 875 /* printf("rn %p, lastb %d\n", rn, lastb);*/ 876 877 /* 878 * This gets complicated because we may delete the node 879 * while applying the function f to it, so we need to calculate 880 * the successor node in advance. 881 */ 882 while (rn->rn_b >= 0) 883 rn = rn->rn_l; 884 885 while (!stopping) { 886 /* printf("node %p (%d)\n", rn, rn->rn_b); */ 887 base = rn; 888 /* If at right child go back up, otherwise, go right */ 889 while (rn->rn_p->rn_r == rn && !(rn->rn_flags & RNF_ROOT)) { 890 rn = rn->rn_p; 891 892 /* if went up beyond last, stop */ 893 if (rn->rn_b < lastb) { 894 stopping = 1; 895 /* printf("up too far\n"); */ 896 } 897 } 898 899 /* Find the next *leaf* since next node might vanish, too */ 900 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 901 rn = rn->rn_l; 902 next = rn; 903 /* Process leaves */ 904 while ((rn = base) != 0) { 905 base = rn->rn_dupedkey; 906 /* printf("leaf %p\n", rn); */ 907 if (!(rn->rn_flags & RNF_ROOT) 908 && (error = (*f)(rn, w))) 909 return (error); 910 } 911 rn = next; 912 913 if (rn->rn_flags & RNF_ROOT) { 914 /* printf("root, stopping"); */ 915 stopping = 1; 916 } 917 918 } 919 return 0; 920} 921 922int 923rn_walktree(h, f, w) 924 struct radix_node_head *h; 925 walktree_f_t *f; 926 void *w; 927{ 928 int error; 929 struct radix_node *base, *next; 930 register struct radix_node *rn = h->rnh_treetop; 931 /* 932 * This gets complicated because we may delete the node 933 * while applying the function f to it, so we need to calculate 934 * the successor node in advance. 935 */ 936 /* First time through node, go left */ 937 while (rn->rn_b >= 0) 938 rn = rn->rn_l; 939 for (;;) { 940 base = rn; 941 /* If at right child go back up, otherwise, go right */ 942 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 943 rn = rn->rn_p; 944 /* Find the next *leaf* since next node might vanish, too */ 945 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 946 rn = rn->rn_l; 947 next = rn; 948 /* Process leaves */ 949 while ((rn = base)) { 950 base = rn->rn_dupedkey; 951 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 952 return (error); 953 } 954 rn = next; 955 if (rn->rn_flags & RNF_ROOT) 956 return (0); 957 } 958 /* NOTREACHED */ 959} 960 961int 962rn_inithead(head, off) 963 void **head; 964 int off; 965{ 966 register struct radix_node_head *rnh; 967 register struct radix_node *t, *tt, *ttt; 968 if (*head) 969 return (1); 970 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 971 if (rnh == 0) 972 return (0); 973 Bzero(rnh, sizeof (*rnh)); 974 *head = rnh; 975 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 976 ttt = rnh->rnh_nodes + 2; 977 t->rn_r = ttt; 978 t->rn_p = t; 979 tt = t->rn_l; 980 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 981 tt->rn_b = -1 - off; 982 *ttt = *tt; 983 ttt->rn_key = rn_ones; 984 rnh->rnh_addaddr = rn_addroute; 985 rnh->rnh_deladdr = rn_delete; 986 rnh->rnh_matchaddr = rn_match; 987 rnh->rnh_lookup = rn_lookup; 988 rnh->rnh_walktree = rn_walktree; 989 rnh->rnh_walktree_from = rn_walktree_from; 990 rnh->rnh_treetop = t; 991 return (1); 992} 993 994void 995rn_init() 996{ 997 char *cp, *cplim; 998#ifdef KERNEL 999 struct domain *dom; 1000 1001 for (dom = domains; dom; dom = dom->dom_next) 1002 if (dom->dom_maxrtkey > max_keylen) 1003 max_keylen = dom->dom_maxrtkey; 1004#endif 1005 if (max_keylen == 0) { 1006 log(LOG_ERR, 1007 "rn_init: radix functions require max_keylen be set\n"); 1008 return; 1009 } 1010 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1011 if (rn_zeros == NULL) 1012 panic("rn_init"); 1013 Bzero(rn_zeros, 3 * max_keylen); 1014 rn_ones = cp = rn_zeros + max_keylen; 1015 addmask_key = cplim = rn_ones + max_keylen; 1016 while (cp < cplim) 1017 *cp++ = -1; 1018 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 1019 panic("rn_init 2"); 1020} 1021