1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32/* 33 * Routines to build and maintain radix trees for routing lookups. 34 */ 35 36#include "defs.h" 37#define log(x, msg) syslog(x, msg) 38#define panic(s) {log(LOG_ERR,s); exit(1);} 39#define min(a,b) (((a)<(b))?(a):(b)) 40 41int max_keylen; 42static struct radix_mask *rn_mkfreelist; 43static struct radix_node_head *mask_rnhead; 44static char *addmask_key; 45static const uint8_t normal_chars[] = 46 { 0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff}; 47static char *rn_zeros, *rn_ones; 48 49#define rn_masktop (mask_rnhead->rnh_treetop) 50#define Bcmp(a, b, l) (l == 0 ? 0 \ 51 : memcmp((caddr_t)(a), (caddr_t)(b), (size_t)l)) 52 53static int rn_satisfies_leaf(char *, struct radix_node *, int); 54static struct radix_node *rn_addmask(void *n_arg, int search, int skip); 55static struct radix_node *rn_addroute(void *v_arg, void *n_arg, 56 struct radix_node_head *head, struct radix_node treenodes[2]); 57static struct radix_node *rn_match(void *v_arg, struct radix_node_head *head); 58 59/* 60 * The data structure for the keys is a radix tree with one way 61 * branching removed. The index rn_b at an internal node n represents a bit 62 * position to be tested. The tree is arranged so that all descendants 63 * of a node n have keys whose bits all agree up to position rn_b - 1. 64 * (We say the index of n is rn_b.) 65 * 66 * There is at least one descendant which has a one bit at position rn_b, 67 * and at least one with a zero there. 68 * 69 * A route is determined by a pair of key and mask. We require that the 70 * bit-wise logical and of the key and mask to be the key. 71 * We define the index of a route to associated with the mask to be 72 * the first bit number in the mask where 0 occurs (with bit number 0 73 * representing the highest order bit). 74 * 75 * We say a mask is normal if every bit is 0, past the index of the mask. 76 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 77 * and m is a normal mask, then the route applies to every descendant of n. 78 * If the index(m) < rn_b, this implies the trailing last few bits of k 79 * before bit b are all 0, (and hence consequently true of every descendant 80 * of n), so the route applies to all descendants of the node as well. 81 * 82 * Similar logic shows that a non-normal mask m such that 83 * index(m) <= index(n) could potentially apply to many children of n. 84 * Thus, for each non-host route, we attach its mask to a list at an internal 85 * node as high in the tree as we can go. 86 * 87 * The present version of the code makes use of normal routes in short- 88 * circuiting an explicit mask and compare operation when testing whether 89 * a key satisfies a normal route, and also in remembering the unique leaf 90 * that governs a subtree. 91 */ 92 93static struct radix_node * 94rn_search(void *v_arg, 95 struct radix_node *head) 96{ 97 struct radix_node *x; 98 caddr_t v; 99 100 for (x = head, v = v_arg; x->rn_b >= 0;) { 101 if (x->rn_bmask & v[x->rn_off]) 102 x = x->rn_r; 103 else 104 x = x->rn_l; 105 } 106 return (x); 107} 108 109static struct radix_node * 110rn_search_m(void *v_arg, 111 struct radix_node *head, 112 void *m_arg) 113{ 114 struct radix_node *x; 115 caddr_t v = v_arg, m = m_arg; 116 117 for (x = head; x->rn_b >= 0;) { 118 if ((x->rn_bmask & m[x->rn_off]) && 119 (x->rn_bmask & v[x->rn_off])) 120 x = x->rn_r; 121 else 122 x = x->rn_l; 123 } 124 return x; 125} 126 127static int 128rn_refines(void* m_arg, void *n_arg) 129{ 130 caddr_t m = m_arg, n = n_arg; 131 caddr_t lim, lim2 = lim = n + *(u_char *)n; 132 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 133 int masks_are_equal = 1; 134 135 if (longer > 0) 136 lim -= longer; 137 while (n < lim) { 138 if (*n & ~(*m)) 139 return 0; 140 if (*n++ != *m++) 141 masks_are_equal = 0; 142 } 143 while (n < lim2) 144 if (*n++) 145 return 0; 146 if (masks_are_equal && (longer < 0)) 147 for (lim2 = m - longer; m < lim2; ) 148 if (*m++) 149 return 1; 150 return (!masks_are_equal); 151} 152 153static struct radix_node * 154rn_lookup(void *v_arg, void *m_arg, struct radix_node_head *head) 155{ 156 struct radix_node *x; 157 caddr_t netmask = 0; 158 159 if (m_arg) { 160 if ((x = rn_addmask(m_arg, 1, 161 head->rnh_treetop->rn_off)) == NULL) 162 return (0); 163 netmask = x->rn_key; 164 } 165 x = rn_match(v_arg, head); 166 if (x && netmask) { 167 while (x && x->rn_mask != netmask) 168 x = x->rn_dupedkey; 169 } 170 return x; 171} 172 173static int 174rn_satisfies_leaf(char *trial, 175 struct radix_node *leaf, 176 int skip) 177{ 178 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 179 char *cplim; 180 int length = min(*(u_char *)cp, *(u_char *)cp2); 181 182 if (cp3 == NULL) 183 cp3 = rn_ones; 184 else 185 length = min(length, *(u_char *)cp3); 186 cplim = cp + length; cp3 += skip; cp2 += skip; 187 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 188 if ((*cp ^ *cp2) & *cp3) 189 return 0; 190 return 1; 191} 192 193static struct radix_node * 194rn_match(void *v_arg, 195 struct radix_node_head *head) 196{ 197 caddr_t v = v_arg; 198 struct radix_node *t = head->rnh_treetop, *x; 199 caddr_t cp = v, cp2; 200 caddr_t cplim; 201 struct radix_node *saved_t, *top = t; 202 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 203 int test, b, rn_b; 204 205 /* 206 * Open code rn_search(v, top) to avoid overhead of extra 207 * subroutine call. 208 */ 209 for (; t->rn_b >= 0; ) { 210 if (t->rn_bmask & cp[t->rn_off]) 211 t = t->rn_r; 212 else 213 t = t->rn_l; 214 } 215 /* 216 * See if we match exactly as a host destination 217 * or at least learn how many bits match, for normal mask finesse. 218 * 219 * It doesn't hurt us to limit how many bytes to check 220 * to the length of the mask, since if it matches we had a genuine 221 * match and the leaf we have is the most specific one anyway; 222 * if it didn't match with a shorter length it would fail 223 * with a long one. This wins big for class B&C netmasks which 224 * are probably the most common case... 225 */ 226 if (t->rn_mask) 227 vlen = *(u_char *)t->rn_mask; 228 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 229 for (; cp < cplim; cp++, cp2++) 230 if (*cp != *cp2) 231 goto on1; 232 /* 233 * This extra grot is in case we are explicitly asked 234 * to look up the default. Ugh! 235 * Or 255.255.255.255 236 * 237 * In this case, we have a complete match of the key. Unless 238 * the node is one of the roots, we are finished. 239 * If it is the zeros root, then take what we have, preferring 240 * any real data. 241 * If it is the ones root, then pretend the target key was followed 242 * by a byte of zeros. 243 */ 244 if (!(t->rn_flags & RNF_ROOT)) 245 return t; /* not a root */ 246 if (t->rn_dupedkey) { 247 t = t->rn_dupedkey; 248 return t; /* have some real data */ 249 } 250 if (*(cp-1) == 0) 251 return t; /* not the ones root */ 252 b = 0; /* fake a zero after 255.255.255.255 */ 253 goto on2; 254on1: 255 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 256 for (b = 7; (test >>= 1) > 0;) 257 b--; 258on2: 259 matched_off = cp - v; 260 b += matched_off << 3; 261 rn_b = -1 - b; 262 /* 263 * If there is a host route in a duped-key chain, it will be first. 264 */ 265 if ((saved_t = t)->rn_mask == 0) 266 t = t->rn_dupedkey; 267 for (; t; t = t->rn_dupedkey) { 268 /* 269 * Even if we don't match exactly as a host, 270 * we may match if the leaf we wound up at is 271 * a route to a net. 272 */ 273 if (t->rn_flags & RNF_NORMAL) { 274 if (rn_b <= t->rn_b) 275 return t; 276 } else if (rn_satisfies_leaf(v, t, matched_off)) { 277 return t; 278 } 279 } 280 t = saved_t; 281 /* start searching up the tree */ 282 do { 283 struct radix_mask *m; 284 t = t->rn_p; 285 if ((m = t->rn_mklist)) { 286 /* 287 * If non-contiguous masks ever become important 288 * we can restore the masking and open coding of 289 * the search and satisfaction test and put the 290 * calculation of "off" back before the "do". 291 */ 292 do { 293 if (m->rm_flags & RNF_NORMAL) { 294 if (rn_b <= m->rm_b) 295 return (m->rm_leaf); 296 } else { 297 off = min(t->rn_off, matched_off); 298 x = rn_search_m(v, t, m->rm_mask); 299 while (x && x->rn_mask != m->rm_mask) 300 x = x->rn_dupedkey; 301 if (x && rn_satisfies_leaf(v, x, off)) 302 return x; 303 } 304 } while ((m = m->rm_mklist)); 305 } 306 } while (t != top); 307 return 0; 308} 309 310#ifdef RN_DEBUG 311int rn_nodenum; 312struct radix_node *rn_clist; 313int rn_saveinfo; 314int rn_debug = 1; 315#endif 316 317static struct radix_node * 318rn_newpair(void *v, int b, struct radix_node nodes[2]) 319{ 320 struct radix_node *tt = nodes, *t = tt + 1; 321 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 322 t->rn_l = tt; t->rn_off = b >> 3; 323 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 324 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 325#ifdef RN_DEBUG 326 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 327 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 328#endif 329 return t; 330} 331 332static struct radix_node * 333rn_insert(void* v_arg, 334 struct radix_node_head *head, 335 int *dupentry, 336 struct radix_node nodes[2]) 337{ 338 caddr_t v = v_arg; 339 struct radix_node *top = head->rnh_treetop; 340 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 341 struct radix_node *t = rn_search(v_arg, top); 342 caddr_t cp = v + head_off; 343 int b; 344 struct radix_node *tt; 345 346 /* 347 * Find first bit at which v and t->rn_key differ 348 */ 349 { 350 caddr_t cp2 = t->rn_key + head_off; 351 int cmp_res; 352 caddr_t cplim = v + vlen; 353 354 while (cp < cplim) 355 if (*cp2++ != *cp++) 356 goto on1; 357 /* handle adding 255.255.255.255 */ 358 if (!(t->rn_flags & RNF_ROOT) || *(cp2-1) == 0) { 359 *dupentry = 1; 360 return t; 361 } 362on1: 363 *dupentry = 0; 364 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 365 for (b = (cp - v) << 3; cmp_res; b--) 366 cmp_res >>= 1; 367 } 368 { 369 struct radix_node *p, *x = top; 370 cp = v; 371 do { 372 p = x; 373 if (cp[x->rn_off] & x->rn_bmask) 374 x = x->rn_r; 375 else x = x->rn_l; 376 } while ((unsigned)b > (unsigned)x->rn_b); 377#ifdef RN_DEBUG 378 if (rn_debug) 379 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 380#endif 381 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 382 if ((cp[p->rn_off] & p->rn_bmask) == 0) 383 p->rn_l = t; 384 else 385 p->rn_r = t; 386 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 387 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 388 t->rn_r = x; 389 } else { 390 t->rn_r = tt; t->rn_l = x; 391 } 392#ifdef RN_DEBUG 393 if (rn_debug) 394 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 395#endif 396 } 397 return (tt); 398} 399 400static struct radix_node * 401rn_addmask(void *n_arg, int search, int skip) 402{ 403 caddr_t netmask = (caddr_t)n_arg; 404 struct radix_node *x; 405 caddr_t cp, cplim; 406 int b = 0, mlen, j; 407 int maskduplicated, m0, isnormal; 408 struct radix_node *saved_x; 409 static int last_zeroed = 0; 410 411 if ((mlen = *(u_char *)netmask) > max_keylen) 412 mlen = max_keylen; 413 if (skip == 0) 414 skip = 1; 415 if (mlen <= skip) 416 return (mask_rnhead->rnh_nodes); 417 if (skip > 1) 418 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 419 if ((m0 = mlen) > skip) 420 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 421 /* 422 * Trim trailing zeroes. 423 */ 424 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 425 cp--; 426 mlen = cp - addmask_key; 427 if (mlen <= skip) { 428 if (m0 >= last_zeroed) 429 last_zeroed = mlen; 430 return (mask_rnhead->rnh_nodes); 431 } 432 if (m0 < last_zeroed) 433 Bzero(addmask_key + m0, last_zeroed - m0); 434 *addmask_key = last_zeroed = mlen; 435 x = rn_search(addmask_key, rn_masktop); 436 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 437 x = NULL; 438 if (x || search) 439 return (x); 440 x = (struct radix_node *)rtmalloc(max_keylen + 2*sizeof(*x), 441 "rn_addmask"); 442 saved_x = x; 443 Bzero(x, max_keylen + 2 * sizeof (*x)); 444 netmask = cp = (caddr_t)(x + 2); 445 Bcopy(addmask_key, cp, mlen); 446 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 447 if (maskduplicated) { 448 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 449 Free(saved_x); 450 return (x); 451 } 452 /* 453 * Calculate index of mask, and check for normalcy. 454 */ 455 cplim = netmask + mlen; isnormal = 1; 456 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 457 cp++; 458 if (cp != cplim) { 459 for (j = 0x80; (j & *cp) != 0; j >>= 1) 460 b++; 461 if (*cp != normal_chars[b] || cp != (cplim - 1)) 462 isnormal = 0; 463 } 464 b += (cp - netmask) << 3; 465 x->rn_b = -1 - b; 466 if (isnormal) 467 x->rn_flags |= RNF_NORMAL; 468 return (x); 469} 470 471static int /* XXX: arbitrary ordering for non-contiguous masks */ 472rn_lexobetter(void *m_arg, void *n_arg) 473{ 474 u_char *mp = m_arg, *np = n_arg, *lim; 475 476 if (*mp > *np) 477 return 1; /* not really, but need to check longer one first */ 478 if (*mp == *np) 479 for (lim = mp + *mp; mp < lim;) 480 if (*mp++ > *np++) 481 return 1; 482 return 0; 483} 484 485static struct radix_mask * 486rn_new_radix_mask(struct radix_node *tt, 487 struct radix_mask *next) 488{ 489 struct radix_mask *m; 490 491 MKGet(m); 492 if (m == NULL) { 493 log(LOG_ERR, "Mask for route not entered\n"); 494 return (0); 495 } 496 Bzero(m, sizeof *m); 497 m->rm_b = tt->rn_b; 498 m->rm_flags = tt->rn_flags; 499 if (tt->rn_flags & RNF_NORMAL) 500 m->rm_leaf = tt; 501 else 502 m->rm_mask = tt->rn_mask; 503 m->rm_mklist = next; 504 tt->rn_mklist = m; 505 return m; 506} 507 508static struct radix_node * 509rn_addroute(void *v_arg, 510 void *n_arg, 511 struct radix_node_head *head, 512 struct radix_node treenodes[2]) 513{ 514 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 515 struct radix_node *t, *x = NULL, *tt; 516 struct radix_node *saved_tt, *top = head->rnh_treetop; 517 short b = 0, b_leaf = 0; 518 int keyduplicated; 519 caddr_t mmask; 520 struct radix_mask *m, **mp; 521 522 /* 523 * In dealing with non-contiguous masks, there may be 524 * many different routes which have the same mask. 525 * We will find it useful to have a unique pointer to 526 * the mask to speed avoiding duplicate references at 527 * nodes and possibly save time in calculating indices. 528 */ 529 if (netmask) { 530 if ((x = rn_addmask(netmask, 0, top->rn_off)) == NULL) 531 return (0); 532 b_leaf = x->rn_b; 533 b = -1 - x->rn_b; 534 netmask = x->rn_key; 535 } 536 /* 537 * Deal with duplicated keys: attach node to previous instance 538 */ 539 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 540 if (keyduplicated) { 541 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 542 if (tt->rn_mask == netmask) 543 return (0); 544 if (netmask == 0 || 545 (tt->rn_mask && 546 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 547 rn_refines(netmask, tt->rn_mask) || 548 rn_lexobetter(netmask, tt->rn_mask)))) 549 break; 550 } 551 /* 552 * If the mask is not duplicated, we wouldn't 553 * find it among possible duplicate key entries 554 * anyway, so the above test doesn't hurt. 555 * 556 * We sort the masks for a duplicated key the same way as 557 * in a masklist -- most specific to least specific. 558 * This may require the unfortunate nuisance of relocating 559 * the head of the list. 560 */ 561 if (tt == saved_tt) { 562 struct radix_node *xx = x; 563 /* link in at head of list */ 564 (tt = treenodes)->rn_dupedkey = t; 565 tt->rn_flags = t->rn_flags; 566 tt->rn_p = x = t->rn_p; 567 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 568 saved_tt = tt; x = xx; 569 } else { 570 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 571 t->rn_dupedkey = tt; 572 } 573#ifdef RN_DEBUG 574 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 575 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 576#endif 577 tt->rn_key = (caddr_t) v; 578 tt->rn_b = -1; 579 tt->rn_flags = RNF_ACTIVE; 580 } 581 /* 582 * Put mask in tree. 583 */ 584 if (netmask) { 585 tt->rn_mask = netmask; 586 tt->rn_b = x->rn_b; 587 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 588 } 589 t = saved_tt->rn_p; 590 if (keyduplicated) 591 goto on2; 592 b_leaf = -1 - t->rn_b; 593 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 594 /* Promote general routes from below */ 595 if (x->rn_b < 0) { 596 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 597 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 598 if ((*mp = m = rn_new_radix_mask(x, 0))) 599 mp = &m->rm_mklist; 600 } 601 } else if (x->rn_mklist) { 602 /* 603 * Skip over masks whose index is > that of new node 604 */ 605 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 606 if (m->rm_b >= b_leaf) 607 break; 608 t->rn_mklist = m; *mp = NULL; 609 } 610on2: 611 /* Add new route to highest possible ancestor's list */ 612 if ((netmask == 0) || (b > t->rn_b )) 613 return tt; /* can't lift at all */ 614 b_leaf = tt->rn_b; 615 do { 616 x = t; 617 t = t->rn_p; 618 } while (b <= t->rn_b && x != top); 619 /* 620 * Search through routes associated with node to 621 * insert new route according to index. 622 * Need same criteria as when sorting dupedkeys to avoid 623 * double loop on deletion. 624 */ 625 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 626 if (m->rm_b < b_leaf) 627 continue; 628 if (m->rm_b > b_leaf) 629 break; 630 if (m->rm_flags & RNF_NORMAL) { 631 mmask = m->rm_leaf->rn_mask; 632 if (tt->rn_flags & RNF_NORMAL) { 633 log(LOG_ERR, 634 "Non-unique normal route, mask not entered"); 635 return tt; 636 } 637 } else 638 mmask = m->rm_mask; 639 if (mmask == netmask) { 640 m->rm_refs++; 641 tt->rn_mklist = m; 642 return tt; 643 } 644 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 645 break; 646 } 647 *mp = rn_new_radix_mask(tt, *mp); 648 return tt; 649} 650 651static struct radix_node * 652rn_delete(void *v_arg, 653 void *netmask_arg, 654 struct radix_node_head *head) 655{ 656 struct radix_node *t, *p, *x, *tt; 657 struct radix_mask *m, *saved_m, **mp; 658 struct radix_node *dupedkey, *saved_tt, *top; 659 caddr_t v, netmask; 660 int b, head_off, vlen; 661 662 v = v_arg; 663 netmask = netmask_arg; 664 x = head->rnh_treetop; 665 tt = rn_search(v, x); 666 head_off = x->rn_off; 667 vlen = *(u_char *)v; 668 saved_tt = tt; 669 top = x; 670 if (tt == NULL || 671 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 672 return (0); 673 /* 674 * Delete our route from mask lists. 675 */ 676 if (netmask) { 677 if ((x = rn_addmask(netmask, 1, head_off)) == NULL) 678 return (0); 679 netmask = x->rn_key; 680 while (tt->rn_mask != netmask) 681 if ((tt = tt->rn_dupedkey) == NULL) 682 return (0); 683 } 684 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == NULL) 685 goto on1; 686 if (tt->rn_flags & RNF_NORMAL) { 687 if (m->rm_leaf != tt || m->rm_refs > 0) { 688 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 689 return 0; /* dangling ref could cause disaster */ 690 } 691 } else { 692 if (m->rm_mask != tt->rn_mask) { 693 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 694 goto on1; 695 } 696 if (--m->rm_refs >= 0) 697 goto on1; 698 } 699 b = -1 - tt->rn_b; 700 t = saved_tt->rn_p; 701 if (b > t->rn_b) 702 goto on1; /* Wasn't lifted at all */ 703 do { 704 x = t; 705 t = t->rn_p; 706 } while (b <= t->rn_b && x != top); 707 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 708 if (m == saved_m) { 709 *mp = m->rm_mklist; 710 MKFree(m); 711 break; 712 } 713 if (m == NULL) { 714 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 715 if (tt->rn_flags & RNF_NORMAL) 716 return (0); /* Dangling ref to us */ 717 } 718on1: 719 /* 720 * Eliminate us from tree 721 */ 722 if (tt->rn_flags & RNF_ROOT) 723 return (0); 724#ifdef RN_DEBUG 725 /* Get us out of the creation list */ 726 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 727 if (t) t->rn_ybro = tt->rn_ybro; 728#endif 729 t = tt->rn_p; 730 if ((dupedkey = saved_tt->rn_dupedkey)) { 731 if (tt == saved_tt) { 732 x = dupedkey; x->rn_p = t; 733 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 734 } else { 735 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 736 p = p->rn_dupedkey; 737 if (p) p->rn_dupedkey = tt->rn_dupedkey; 738 else log(LOG_ERR, "rn_delete: couldn't find us\n"); 739 } 740 t = tt + 1; 741 if (t->rn_flags & RNF_ACTIVE) { 742#ifndef RN_DEBUG 743 *++x = *t; p = t->rn_p; 744#else 745 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 746#endif 747 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 748 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 749 } 750 goto out; 751 } 752 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 753 p = t->rn_p; 754 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 755 x->rn_p = p; 756 /* 757 * Demote routes attached to us. 758 */ 759 if (t->rn_mklist) { 760 if (x->rn_b >= 0) { 761 for (mp = &x->rn_mklist; (m = *mp);) 762 mp = &m->rm_mklist; 763 *mp = t->rn_mklist; 764 } else { 765 /* If there are any key,mask pairs in a sibling 766 duped-key chain, some subset will appear sorted 767 in the same order attached to our mklist */ 768 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 769 if (m == x->rn_mklist) { 770 struct radix_mask *mm = m->rm_mklist; 771 x->rn_mklist = 0; 772 if (--(m->rm_refs) < 0) 773 MKFree(m); 774 m = mm; 775 } 776 if (m) 777 syslog(LOG_ERR, "%s 0x%lx at 0x%lx\n", 778 "rn_delete: Orphaned Mask", 779 (unsigned long)m, 780 (unsigned long)x); 781 } 782 } 783 /* 784 * We may be holding an active internal node in the tree. 785 */ 786 x = tt + 1; 787 if (t != x) { 788#ifndef RN_DEBUG 789 *t = *x; 790#else 791 b = t->rn_info; *t = *x; t->rn_info = b; 792#endif 793 t->rn_l->rn_p = t; t->rn_r->rn_p = t; 794 p = x->rn_p; 795 if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; 796 } 797out: 798 tt->rn_flags &= ~RNF_ACTIVE; 799 tt[1].rn_flags &= ~RNF_ACTIVE; 800 return (tt); 801} 802 803int 804rn_walktree(struct radix_node_head *h, 805 int (*f)(struct radix_node *, struct walkarg *), 806 struct walkarg *w) 807{ 808 int error; 809 struct radix_node *base, *next; 810 struct radix_node *rn = h->rnh_treetop; 811 /* 812 * This gets complicated because we may delete the node 813 * while applying the function f to it, so we need to calculate 814 * the successor node in advance. 815 */ 816 /* First time through node, go left */ 817 while (rn->rn_b >= 0) 818 rn = rn->rn_l; 819 for (;;) { 820 base = rn; 821 /* If at right child go back up, otherwise, go right */ 822 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 823 rn = rn->rn_p; 824 /* Find the next *leaf* since next node might vanish, too */ 825 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 826 rn = rn->rn_l; 827 next = rn; 828 /* Process leaves */ 829 while ((rn = base)) { 830 base = rn->rn_dupedkey; 831 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 832 return (error); 833 } 834 rn = next; 835 if (rn->rn_flags & RNF_ROOT) 836 return (0); 837 } 838 /* NOTREACHED */ 839} 840 841int 842rn_inithead(struct radix_node_head **head, int off) 843{ 844 struct radix_node_head *rnh; 845 struct radix_node *t, *tt, *ttt; 846 if (*head) 847 return (1); 848 rnh = (struct radix_node_head *)rtmalloc(sizeof(*rnh), "rn_inithead"); 849 Bzero(rnh, sizeof (*rnh)); 850 *head = rnh; 851 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 852 ttt = rnh->rnh_nodes + 2; 853 t->rn_r = ttt; 854 t->rn_p = t; 855 tt = t->rn_l; 856 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 857 tt->rn_b = -1 - off; 858 *ttt = *tt; 859 ttt->rn_key = rn_ones; 860 rnh->rnh_addaddr = rn_addroute; 861 rnh->rnh_deladdr = rn_delete; 862 rnh->rnh_matchaddr = rn_match; 863 rnh->rnh_lookup = rn_lookup; 864 rnh->rnh_walktree = rn_walktree; 865 rnh->rnh_treetop = t; 866 return (1); 867} 868 869void 870rn_init(void) 871{ 872 char *cp, *cplim; 873 if (max_keylen == 0) { 874 printf("rn_init: radix functions require max_keylen be set\n"); 875 return; 876 } 877 rn_zeros = (char *)rtmalloc(3 * max_keylen, "rn_init"); 878 Bzero(rn_zeros, 3 * max_keylen); 879 rn_ones = cp = rn_zeros + max_keylen; 880 addmask_key = cplim = rn_ones + max_keylen; 881 while (cp < cplim) 882 *cp++ = -1; 883 if (rn_inithead(&mask_rnhead, 0) == 0) 884 panic("rn_init 2"); 885} 886 887