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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)radix.c 8.4 (Berkeley) 11/2/94 30 * 31 * $FreeBSD$ 32 */ 33 34 /* 35 * Routines to build and maintain radix trees for routing lookups. 36 */ 37 38 #include "defs.h" 39 40 #ifdef __NetBSD__ 41 __RCSID("$NetBSD$"); 42 #elif defined(__FreeBSD__) 43 __RCSID("$FreeBSD$"); 44 #else 45 __RCSID("$Revision: 2.23 $"); 46 #ident "$Revision: 2.23 $" 47 #endif 48 49 #define log(x, msg) syslog(x, msg) 50 #define panic(s) {log(LOG_ERR,s); exit(1);} 51 #define min(a,b) (((a)<(b))?(a):(b)) 52 53 int max_keylen; 54 struct radix_mask *rn_mkfreelist; 55 struct radix_node_head *mask_rnhead; 56 static char *addmask_key; 57 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 58 static char *rn_zeros, *rn_ones; 59 60 #define rn_masktop (mask_rnhead->rnh_treetop) 61 #undef Bcmp 62 #define Bcmp(a, b, l) (l == 0 ? 0 \ 63 : memcmp((caddr_t)(a), (caddr_t)(b), (size_t)l)) 64 65 static int rn_satisfies_leaf(char *, struct radix_node *, int); 66 67 /* 68 * The data structure for the keys is a radix tree with one way 69 * branching removed. The index rn_b at an internal node n represents a bit 70 * position to be tested. The tree is arranged so that all descendants 71 * of a node n have keys whose bits all agree up to position rn_b - 1. 72 * (We say the index of n is rn_b.) 73 * 74 * There is at least one descendant which has a one bit at position rn_b, 75 * and at least one with a zero there. 76 * 77 * A route is determined by a pair of key and mask. We require that the 78 * bit-wise logical and of the key and mask to be the key. 79 * We define the index of a route to associated with the mask to be 80 * the first bit number in the mask where 0 occurs (with bit number 0 81 * representing the highest order bit). 82 * 83 * We say a mask is normal if every bit is 0, past the index of the mask. 84 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 85 * and m is a normal mask, then the route applies to every descendant of n. 86 * If the index(m) < rn_b, this implies the trailing last few bits of k 87 * before bit b are all 0, (and hence consequently true of every descendant 88 * of n), so the route applies to all descendants of the node as well. 89 * 90 * Similar logic shows that a non-normal mask m such that 91 * index(m) <= index(n) could potentially apply to many children of n. 92 * Thus, for each non-host route, we attach its mask to a list at an internal 93 * node as high in the tree as we can go. 94 * 95 * The present version of the code makes use of normal routes in short- 96 * circuiting an explict mask and compare operation when testing whether 97 * a key satisfies a normal route, and also in remembering the unique leaf 98 * that governs a subtree. 99 */ 100 101 struct radix_node * 102 rn_search(void *v_arg, 103 struct radix_node *head) 104 { 105 struct radix_node *x; 106 caddr_t v; 107 108 for (x = head, v = v_arg; x->rn_b >= 0;) { 109 if (x->rn_bmask & v[x->rn_off]) 110 x = x->rn_r; 111 else 112 x = x->rn_l; 113 } 114 return (x); 115 } 116 117 struct radix_node * 118 rn_search_m(void *v_arg, 119 struct radix_node *head, 120 void *m_arg) 121 { 122 struct radix_node *x; 123 caddr_t v = v_arg, m = m_arg; 124 125 for (x = head; x->rn_b >= 0;) { 126 if ((x->rn_bmask & m[x->rn_off]) && 127 (x->rn_bmask & v[x->rn_off])) 128 x = x->rn_r; 129 else 130 x = x->rn_l; 131 } 132 return x; 133 } 134 135 int 136 rn_refines(void* m_arg, void *n_arg) 137 { 138 caddr_t m = m_arg, n = n_arg; 139 caddr_t lim, lim2 = lim = n + *(u_char *)n; 140 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 141 int masks_are_equal = 1; 142 143 if (longer > 0) 144 lim -= longer; 145 while (n < lim) { 146 if (*n & ~(*m)) 147 return 0; 148 if (*n++ != *m++) 149 masks_are_equal = 0; 150 } 151 while (n < lim2) 152 if (*n++) 153 return 0; 154 if (masks_are_equal && (longer < 0)) 155 for (lim2 = m - longer; m < lim2; ) 156 if (*m++) 157 return 1; 158 return (!masks_are_equal); 159 } 160 161 struct radix_node * 162 rn_lookup(void *v_arg, void *m_arg, struct radix_node_head *head) 163 { 164 struct radix_node *x; 165 caddr_t netmask = 0; 166 167 if (m_arg) { 168 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 169 return (0); 170 netmask = x->rn_key; 171 } 172 x = rn_match(v_arg, head); 173 if (x && netmask) { 174 while (x && x->rn_mask != netmask) 175 x = x->rn_dupedkey; 176 } 177 return x; 178 } 179 180 static int 181 rn_satisfies_leaf(char *trial, 182 struct radix_node *leaf, 183 int skip) 184 { 185 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 186 char *cplim; 187 int length = min(*(u_char *)cp, *(u_char *)cp2); 188 189 if (cp3 == 0) 190 cp3 = rn_ones; 191 else 192 length = min(length, *(u_char *)cp3); 193 cplim = cp + length; cp3 += skip; cp2 += skip; 194 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 195 if ((*cp ^ *cp2) & *cp3) 196 return 0; 197 return 1; 198 } 199 200 struct radix_node * 201 rn_match(void *v_arg, 202 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 * Or 255.255.255.255 243 * 244 * In this case, we have a complete match of the key. Unless 245 * the node is one of the roots, we are finished. 246 * If it is the zeros root, then take what we have, prefering 247 * any real data. 248 * If it is the ones root, then pretend the target key was followed 249 * by a byte of zeros. 250 */ 251 if (!(t->rn_flags & RNF_ROOT)) 252 return t; /* not a root */ 253 if (t->rn_dupedkey) { 254 t = t->rn_dupedkey; 255 return t; /* have some real data */ 256 } 257 if (*(cp-1) == 0) 258 return t; /* not the ones root */ 259 b = 0; /* fake a zero after 255.255.255.255 */ 260 goto on2; 261 on1: 262 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 263 for (b = 7; (test >>= 1) > 0;) 264 b--; 265 on2: 266 matched_off = cp - v; 267 b += matched_off << 3; 268 rn_b = -1 - b; 269 /* 270 * If there is a host route in a duped-key chain, it will be first. 271 */ 272 if ((saved_t = t)->rn_mask == 0) 273 t = t->rn_dupedkey; 274 for (; t; t = t->rn_dupedkey) { 275 /* 276 * Even if we don't match exactly as a host, 277 * we may match if the leaf we wound up at is 278 * a route to a net. 279 */ 280 if (t->rn_flags & RNF_NORMAL) { 281 if (rn_b <= t->rn_b) 282 return t; 283 } else if (rn_satisfies_leaf(v, t, matched_off)) { 284 return t; 285 } 286 } 287 t = saved_t; 288 /* start searching up the tree */ 289 do { 290 struct radix_mask *m; 291 t = t->rn_p; 292 if ((m = t->rn_mklist)) { 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_satisfies_leaf(v, x, off)) 309 return x; 310 } 311 } while ((m = m->rm_mklist)); 312 } 313 } while (t != top); 314 return 0; 315 } 316 317 #ifdef RN_DEBUG 318 int rn_nodenum; 319 struct radix_node *rn_clist; 320 int rn_saveinfo; 321 int rn_debug = 1; 322 #endif 323 324 struct radix_node * 325 rn_newpair(void *v, int b, struct radix_node nodes[2]) 326 { 327 struct radix_node *tt = nodes, *t = tt + 1; 328 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 329 t->rn_l = tt; t->rn_off = b >> 3; 330 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 331 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 332 #ifdef RN_DEBUG 333 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 334 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 335 #endif 336 return t; 337 } 338 339 struct radix_node * 340 rn_insert(void* v_arg, 341 struct radix_node_head *head, 342 int *dupentry, 343 struct radix_node nodes[2]) 344 { 345 caddr_t v = v_arg; 346 struct radix_node *top = head->rnh_treetop; 347 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 348 struct radix_node *t = rn_search(v_arg, top); 349 caddr_t cp = v + head_off; 350 int b; 351 struct radix_node *tt; 352 353 /* 354 * Find first bit at which v and t->rn_key differ 355 */ 356 { 357 caddr_t cp2 = t->rn_key + head_off; 358 int cmp_res; 359 caddr_t cplim = v + vlen; 360 361 while (cp < cplim) 362 if (*cp2++ != *cp++) 363 goto on1; 364 /* handle adding 255.255.255.255 */ 365 if (!(t->rn_flags & RNF_ROOT) || *(cp2-1) == 0) { 366 *dupentry = 1; 367 return t; 368 } 369 on1: 370 *dupentry = 0; 371 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 372 for (b = (cp - v) << 3; cmp_res; b--) 373 cmp_res >>= 1; 374 } 375 { 376 struct radix_node *p, *x = top; 377 cp = v; 378 do { 379 p = x; 380 if (cp[x->rn_off] & x->rn_bmask) 381 x = x->rn_r; 382 else x = x->rn_l; 383 } while ((unsigned)b > (unsigned)x->rn_b); 384 #ifdef RN_DEBUG 385 if (rn_debug) 386 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 387 #endif 388 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 389 if ((cp[p->rn_off] & p->rn_bmask) == 0) 390 p->rn_l = t; 391 else 392 p->rn_r = t; 393 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 394 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 395 t->rn_r = x; 396 } else { 397 t->rn_r = tt; t->rn_l = x; 398 } 399 #ifdef RN_DEBUG 400 if (rn_debug) 401 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 402 #endif 403 } 404 return (tt); 405 } 406 407 struct radix_node * 408 rn_addmask(void *n_arg, int search, int skip) 409 { 410 caddr_t netmask = (caddr_t)n_arg; 411 struct radix_node *x; 412 caddr_t cp, cplim; 413 int b = 0, mlen, j; 414 int maskduplicated, m0, isnormal; 415 struct radix_node *saved_x; 416 static int last_zeroed = 0; 417 418 if ((mlen = *(u_char *)netmask) > max_keylen) 419 mlen = max_keylen; 420 if (skip == 0) 421 skip = 1; 422 if (mlen <= skip) 423 return (mask_rnhead->rnh_nodes); 424 if (skip > 1) 425 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 426 if ((m0 = mlen) > skip) 427 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 428 /* 429 * Trim trailing zeroes. 430 */ 431 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 432 cp--; 433 mlen = cp - addmask_key; 434 if (mlen <= skip) { 435 if (m0 >= last_zeroed) 436 last_zeroed = mlen; 437 return (mask_rnhead->rnh_nodes); 438 } 439 if (m0 < last_zeroed) 440 Bzero(addmask_key + m0, last_zeroed - m0); 441 *addmask_key = last_zeroed = mlen; 442 x = rn_search(addmask_key, rn_masktop); 443 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 444 x = 0; 445 if (x || search) 446 return (x); 447 x = (struct radix_node *)rtmalloc(max_keylen + 2*sizeof(*x), 448 "rn_addmask"); 449 saved_x = x; 450 Bzero(x, max_keylen + 2 * sizeof (*x)); 451 netmask = cp = (caddr_t)(x + 2); 452 Bcopy(addmask_key, cp, mlen); 453 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 454 if (maskduplicated) { 455 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 456 Free(saved_x); 457 return (x); 458 } 459 /* 460 * Calculate index of mask, and check for normalcy. 461 */ 462 cplim = netmask + mlen; isnormal = 1; 463 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 464 cp++; 465 if (cp != cplim) { 466 for (j = 0x80; (j & *cp) != 0; j >>= 1) 467 b++; 468 if (*cp != normal_chars[b] || cp != (cplim - 1)) 469 isnormal = 0; 470 } 471 b += (cp - netmask) << 3; 472 x->rn_b = -1 - b; 473 if (isnormal) 474 x->rn_flags |= RNF_NORMAL; 475 return (x); 476 } 477 478 static int /* XXX: arbitrary ordering for non-contiguous masks */ 479 rn_lexobetter(void *m_arg, void *n_arg) 480 { 481 u_char *mp = m_arg, *np = n_arg, *lim; 482 483 if (*mp > *np) 484 return 1; /* not really, but need to check longer one first */ 485 if (*mp == *np) 486 for (lim = mp + *mp; mp < lim;) 487 if (*mp++ > *np++) 488 return 1; 489 return 0; 490 } 491 492 static struct radix_mask * 493 rn_new_radix_mask(struct radix_node *tt, 494 struct radix_mask *next) 495 { 496 struct radix_mask *m; 497 498 MKGet(m); 499 if (m == 0) { 500 log(LOG_ERR, "Mask for route not entered\n"); 501 return (0); 502 } 503 Bzero(m, sizeof *m); 504 m->rm_b = tt->rn_b; 505 m->rm_flags = tt->rn_flags; 506 if (tt->rn_flags & RNF_NORMAL) 507 m->rm_leaf = tt; 508 else 509 m->rm_mask = tt->rn_mask; 510 m->rm_mklist = next; 511 tt->rn_mklist = m; 512 return m; 513 } 514 515 struct radix_node * 516 rn_addroute(void *v_arg, 517 void *n_arg, 518 struct radix_node_head *head, 519 struct radix_node treenodes[2]) 520 { 521 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 522 struct radix_node *t, *x = 0, *tt; 523 struct radix_node *saved_tt, *top = head->rnh_treetop; 524 short b = 0, b_leaf = 0; 525 int keyduplicated; 526 caddr_t mmask; 527 struct radix_mask *m, **mp; 528 529 /* 530 * In dealing with non-contiguous masks, there may be 531 * many different routes which have the same mask. 532 * We will find it useful to have a unique pointer to 533 * the mask to speed avoiding duplicate references at 534 * nodes and possibly save time in calculating indices. 535 */ 536 if (netmask) { 537 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 538 return (0); 539 b_leaf = x->rn_b; 540 b = -1 - x->rn_b; 541 netmask = x->rn_key; 542 } 543 /* 544 * Deal with duplicated keys: attach node to previous instance 545 */ 546 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 547 if (keyduplicated) { 548 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 549 if (tt->rn_mask == netmask) 550 return (0); 551 if (netmask == 0 || 552 (tt->rn_mask && 553 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 554 rn_refines(netmask, tt->rn_mask) || 555 rn_lexobetter(netmask, tt->rn_mask)))) 556 break; 557 } 558 /* 559 * If the mask is not duplicated, we wouldn't 560 * find it among possible duplicate key entries 561 * anyway, so the above test doesn't hurt. 562 * 563 * We sort the masks for a duplicated key the same way as 564 * in a masklist -- most specific to least specific. 565 * This may require the unfortunate nuisance of relocating 566 * the head of the list. 567 */ 568 if (tt == saved_tt) { 569 struct radix_node *xx = x; 570 /* link in at head of list */ 571 (tt = treenodes)->rn_dupedkey = t; 572 tt->rn_flags = t->rn_flags; 573 tt->rn_p = x = t->rn_p; 574 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 575 saved_tt = tt; x = xx; 576 } else { 577 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 578 t->rn_dupedkey = tt; 579 } 580 #ifdef RN_DEBUG 581 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 582 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 583 #endif 584 tt->rn_key = (caddr_t) v; 585 tt->rn_b = -1; 586 tt->rn_flags = RNF_ACTIVE; 587 } 588 /* 589 * Put mask in tree. 590 */ 591 if (netmask) { 592 tt->rn_mask = netmask; 593 tt->rn_b = x->rn_b; 594 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 595 } 596 t = saved_tt->rn_p; 597 if (keyduplicated) 598 goto on2; 599 b_leaf = -1 - t->rn_b; 600 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 601 /* Promote general routes from below */ 602 if (x->rn_b < 0) { 603 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 604 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 605 if ((*mp = m = rn_new_radix_mask(x, 0))) 606 mp = &m->rm_mklist; 607 } 608 } else if (x->rn_mklist) { 609 /* 610 * Skip over masks whose index is > that of new node 611 */ 612 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 613 if (m->rm_b >= b_leaf) 614 break; 615 t->rn_mklist = m; *mp = 0; 616 } 617 on2: 618 /* Add new route to highest possible ancestor's list */ 619 if ((netmask == 0) || (b > t->rn_b )) 620 return tt; /* can't lift at all */ 621 b_leaf = tt->rn_b; 622 do { 623 x = t; 624 t = t->rn_p; 625 } while (b <= t->rn_b && x != top); 626 /* 627 * Search through routes associated with node to 628 * insert new route according to index. 629 * Need same criteria as when sorting dupedkeys to avoid 630 * double loop on deletion. 631 */ 632 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 633 if (m->rm_b < b_leaf) 634 continue; 635 if (m->rm_b > b_leaf) 636 break; 637 if (m->rm_flags & RNF_NORMAL) { 638 mmask = m->rm_leaf->rn_mask; 639 if (tt->rn_flags & RNF_NORMAL) { 640 log(LOG_ERR, 641 "Non-unique normal route, mask not entered"); 642 return tt; 643 } 644 } else 645 mmask = m->rm_mask; 646 if (mmask == netmask) { 647 m->rm_refs++; 648 tt->rn_mklist = m; 649 return tt; 650 } 651 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 652 break; 653 } 654 *mp = rn_new_radix_mask(tt, *mp); 655 return tt; 656 } 657 658 struct radix_node * 659 rn_delete(void *v_arg, 660 void *netmask_arg, 661 struct radix_node_head *head) 662 { 663 struct radix_node *t, *p, *x, *tt; 664 struct radix_mask *m, *saved_m, **mp; 665 struct radix_node *dupedkey, *saved_tt, *top; 666 caddr_t v, netmask; 667 int b, head_off, vlen; 668 669 v = v_arg; 670 netmask = netmask_arg; 671 x = head->rnh_treetop; 672 tt = rn_search(v, x); 673 head_off = x->rn_off; 674 vlen = *(u_char *)v; 675 saved_tt = tt; 676 top = x; 677 if (tt == 0 || 678 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 679 return (0); 680 /* 681 * Delete our route from mask lists. 682 */ 683 if (netmask) { 684 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 685 return (0); 686 netmask = x->rn_key; 687 while (tt->rn_mask != netmask) 688 if ((tt = tt->rn_dupedkey) == 0) 689 return (0); 690 } 691 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 692 goto on1; 693 if (tt->rn_flags & RNF_NORMAL) { 694 if (m->rm_leaf != tt || m->rm_refs > 0) { 695 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 696 return 0; /* dangling ref could cause disaster */ 697 } 698 } else { 699 if (m->rm_mask != tt->rn_mask) { 700 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 701 goto on1; 702 } 703 if (--m->rm_refs >= 0) 704 goto on1; 705 } 706 b = -1 - tt->rn_b; 707 t = saved_tt->rn_p; 708 if (b > t->rn_b) 709 goto on1; /* Wasn't lifted at all */ 710 do { 711 x = t; 712 t = t->rn_p; 713 } while (b <= t->rn_b && x != top); 714 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 715 if (m == saved_m) { 716 *mp = m->rm_mklist; 717 MKFree(m); 718 break; 719 } 720 if (m == 0) { 721 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 722 if (tt->rn_flags & RNF_NORMAL) 723 return (0); /* Dangling ref to us */ 724 } 725 on1: 726 /* 727 * Eliminate us from tree 728 */ 729 if (tt->rn_flags & RNF_ROOT) 730 return (0); 731 #ifdef RN_DEBUG 732 /* Get us out of the creation list */ 733 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 734 if (t) t->rn_ybro = tt->rn_ybro; 735 #endif 736 t = tt->rn_p; 737 if ((dupedkey = saved_tt->rn_dupedkey)) { 738 if (tt == saved_tt) { 739 x = dupedkey; x->rn_p = t; 740 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 741 } else { 742 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 743 p = p->rn_dupedkey; 744 if (p) p->rn_dupedkey = tt->rn_dupedkey; 745 else log(LOG_ERR, "rn_delete: couldn't find us\n"); 746 } 747 t = tt + 1; 748 if (t->rn_flags & RNF_ACTIVE) { 749 #ifndef RN_DEBUG 750 *++x = *t; p = t->rn_p; 751 #else 752 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 753 #endif 754 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 755 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 756 } 757 goto out; 758 } 759 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 760 p = t->rn_p; 761 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 762 x->rn_p = p; 763 /* 764 * Demote routes attached to us. 765 */ 766 if (t->rn_mklist) { 767 if (x->rn_b >= 0) { 768 for (mp = &x->rn_mklist; (m = *mp);) 769 mp = &m->rm_mklist; 770 *mp = t->rn_mklist; 771 } else { 772 /* If there are any key,mask pairs in a sibling 773 duped-key chain, some subset will appear sorted 774 in the same order attached to our mklist */ 775 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 776 if (m == x->rn_mklist) { 777 struct radix_mask *mm = m->rm_mklist; 778 x->rn_mklist = 0; 779 if (--(m->rm_refs) < 0) 780 MKFree(m); 781 m = mm; 782 } 783 if (m) 784 syslog(LOG_ERR, "%s 0x%lx at 0x%lx\n", 785 "rn_delete: Orphaned Mask", 786 (unsigned long)m, 787 (unsigned long)x); 788 } 789 } 790 /* 791 * We may be holding an active internal node in the tree. 792 */ 793 x = tt + 1; 794 if (t != x) { 795 #ifndef RN_DEBUG 796 *t = *x; 797 #else 798 b = t->rn_info; *t = *x; t->rn_info = b; 799 #endif 800 t->rn_l->rn_p = t; t->rn_r->rn_p = t; 801 p = x->rn_p; 802 if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; 803 } 804 out: 805 tt->rn_flags &= ~RNF_ACTIVE; 806 tt[1].rn_flags &= ~RNF_ACTIVE; 807 return (tt); 808 } 809 810 int 811 rn_walktree(struct radix_node_head *h, 812 int (*f)(struct radix_node *, struct walkarg *), 813 struct walkarg *w) 814 { 815 int error; 816 struct radix_node *base, *next; 817 struct radix_node *rn = h->rnh_treetop; 818 /* 819 * This gets complicated because we may delete the node 820 * while applying the function f to it, so we need to calculate 821 * the successor node in advance. 822 */ 823 /* First time through node, go left */ 824 while (rn->rn_b >= 0) 825 rn = rn->rn_l; 826 for (;;) { 827 base = rn; 828 /* If at right child go back up, otherwise, go right */ 829 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 830 rn = rn->rn_p; 831 /* Find the next *leaf* since next node might vanish, too */ 832 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 833 rn = rn->rn_l; 834 next = rn; 835 /* Process leaves */ 836 while ((rn = base)) { 837 base = rn->rn_dupedkey; 838 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 839 return (error); 840 } 841 rn = next; 842 if (rn->rn_flags & RNF_ROOT) 843 return (0); 844 } 845 /* NOTREACHED */ 846 } 847 848 int 849 rn_inithead(void **head, int off) 850 { 851 struct radix_node_head *rnh; 852 struct radix_node *t, *tt, *ttt; 853 if (*head) 854 return (1); 855 rnh = (struct radix_node_head *)rtmalloc(sizeof(*rnh), "rn_inithead"); 856 Bzero(rnh, sizeof (*rnh)); 857 *head = rnh; 858 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 859 ttt = rnh->rnh_nodes + 2; 860 t->rn_r = ttt; 861 t->rn_p = t; 862 tt = t->rn_l; 863 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 864 tt->rn_b = -1 - off; 865 *ttt = *tt; 866 ttt->rn_key = rn_ones; 867 rnh->rnh_addaddr = rn_addroute; 868 rnh->rnh_deladdr = rn_delete; 869 rnh->rnh_matchaddr = rn_match; 870 rnh->rnh_lookup = rn_lookup; 871 rnh->rnh_walktree = rn_walktree; 872 rnh->rnh_treetop = t; 873 return (1); 874 } 875 876 void 877 rn_init(void) 878 { 879 char *cp, *cplim; 880 if (max_keylen == 0) { 881 printf("rn_init: radix functions require max_keylen be set\n"); 882 return; 883 } 884 rn_zeros = (char *)rtmalloc(3 * max_keylen, "rn_init"); 885 Bzero(rn_zeros, 3 * max_keylen); 886 rn_ones = cp = rn_zeros + max_keylen; 887 addmask_key = cplim = rn_ones + max_keylen; 888 while (cp < cplim) 889 *cp++ = -1; 890 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 891 panic("rn_init 2"); 892 } 893 894