1 /* 2 * Copyright 2001-2003 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgment: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)radix.c 8.4 (Berkeley) 11/2/94 37 * 38 * $FreeBSD: src/sbin/routed/radix.c,v 1.6 2000/08/11 08:24:38 sheldonh Exp $ 39 */ 40 41 #pragma ident "%Z%%M% %I% %E% SMI" 42 43 /* 44 * Routines to build and maintain radix trees for routing lookups. 45 */ 46 47 #include "defs.h" 48 49 static const size_t max_keylen = sizeof (struct sockaddr_in); 50 static struct radix_mask *rn_mkfreelist; 51 static struct radix_node_head *mask_rnhead; 52 static uint8_t *rn_zeros, *rn_ones, *addmask_key; 53 54 #define rn_masktop (mask_rnhead->rnh_treetop) 55 56 static boolean_t rn_satisfies_leaf(uint8_t *, struct radix_node *, int); 57 58 static boolean_t rn_refines(void *, void *); 59 60 static struct radix_node 61 *rn_addmask(void *, uint_t, uint_t), 62 *rn_addroute(void *, void *, struct radix_node_head *, 63 struct radix_node [2]), 64 *rn_delete(void *, void *, struct radix_node_head *), 65 *rn_insert(void *, struct radix_node_head *, boolean_t *, 66 struct radix_node [2]), 67 *rn_match(void *, struct radix_node_head *), 68 *rn_newpair(void *, uint_t, struct radix_node[2]), 69 *rn_search(void *, struct radix_node *), 70 *rn_search_m(void *, struct radix_node *, void *); 71 72 static struct radix_node *rn_lookup(void *, void *, struct radix_node_head *); 73 74 #ifdef DEBUG 75 #define DBGMSG(x) msglog x 76 #else 77 #define DBGMSG(x) (void) 0 78 #endif 79 80 /* 81 * The data structure for the keys is a radix tree with one way 82 * branching removed. The index rn_b at an internal node n represents a bit 83 * position to be tested. The tree is arranged so that all descendants 84 * of a node n have keys whose bits all agree up to position rn_b - 1. 85 * (We say the index of n is rn_b.) 86 * 87 * There is at least one descendant which has a one bit at position rn_b, 88 * and at least one with a zero there. 89 * 90 * A route is determined by a pair of key and mask. We require that the 91 * bit-wise logical and of the key and mask to be the key. 92 * We define the index of a route to associated with the mask to be 93 * the first bit number in the mask where 0 occurs (with bit number 0 94 * representing the highest order bit). 95 * 96 * We say a mask is normal if every bit is 0, past the index of the mask. 97 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 98 * and m is a normal mask, then the route applies to every descendant of n. 99 * If the index(m) < rn_b, this implies the trailing last few bits of k 100 * before bit b are all 0, (and hence consequently true of every descendant 101 * of n), so the route applies to all descendants of the node as well. 102 * 103 * Similar logic shows that a non-normal mask m such that 104 * index(m) <= index(n) could potentially apply to many children of n. 105 * Thus, for each non-host route, we attach its mask to a list at an internal 106 * node as high in the tree as we can go. 107 * 108 * The present version of the code makes use of normal routes in short- 109 * circuiting an explict mask and compare operation when testing whether 110 * a key satisfies a normal route, and also in remembering the unique leaf 111 * that governs a subtree. 112 */ 113 114 static struct radix_node * 115 rn_search(void *v_arg, struct radix_node *head) 116 { 117 struct radix_node *x; 118 uint8_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 } 128 129 static struct radix_node * 130 rn_search_m(void *v_arg, struct radix_node *head, void *m_arg) 131 { 132 struct radix_node *x; 133 uint8_t *v = v_arg, *m = m_arg; 134 135 for (x = head; x->rn_b >= 0; ) { 136 if (x->rn_bmask & m[x->rn_off] & v[x->rn_off]) 137 x = x->rn_r; 138 else 139 x = x->rn_l; 140 } 141 return (x); 142 } 143 144 /* 145 * Returns true if there are no bits set in n_arg that are zero in 146 * m_arg and the masks aren't equal. In other words, it returns true 147 * when m_arg is a finer-granularity netmask -- it represents a subset 148 * of the destinations implied by n_arg. 149 */ 150 static boolean_t 151 rn_refines(void* m_arg, void *n_arg) 152 { 153 uint8_t *m = m_arg, *n = n_arg; 154 uint8_t *lim; 155 boolean_t masks_are_equal = _B_TRUE; 156 157 lim = n + sizeof (struct sockaddr); 158 159 while (n < lim) { 160 if (*n & ~(*m)) 161 return (_B_FALSE); 162 if (*n++ != *m++) 163 masks_are_equal = _B_FALSE; 164 } 165 return (!masks_are_equal); 166 } 167 168 static struct radix_node * 169 rn_lookup(void *v_arg, void *m_arg, struct radix_node_head *head) 170 { 171 struct radix_node *x; 172 uint8_t *netmask = NULL; 173 174 if (m_arg) { 175 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 176 NULL) { 177 DBGMSG(("rn_lookup: failed to add mask")); 178 return (NULL); 179 } 180 netmask = x->rn_key; 181 } 182 x = rn_match(v_arg, head); 183 if (x && netmask) { 184 while (x && x->rn_mask != netmask) 185 x = x->rn_dupedkey; 186 } 187 return (x); 188 } 189 190 /* 191 * Returns true if address 'trial' has no bits differing from the 192 * leaf's key when compared under the leaf's mask. In other words, 193 * returns true when 'trial' matches leaf. 194 */ 195 static boolean_t 196 rn_satisfies_leaf(uint8_t *trial, 197 struct radix_node *leaf, 198 int skip) 199 { 200 uint8_t *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 201 uint8_t *cplim; 202 size_t length; 203 204 length = sizeof (struct sockaddr); 205 206 if (cp3 == NULL) 207 cp3 = rn_ones; 208 cplim = cp + length; 209 cp3 += skip; 210 cp2 += skip; 211 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 212 if ((*cp ^ *cp2) & *cp3) 213 return (_B_FALSE); 214 return (_B_TRUE); 215 } 216 217 static struct radix_node * 218 rn_match(void *v_arg, struct radix_node_head *head) 219 { 220 uint8_t *v = v_arg; 221 struct radix_node *t = head->rnh_treetop, *x; 222 uint8_t *cp = v, *cp2; 223 uint8_t *cplim; 224 struct radix_node *saved_t, *top = t; 225 uint_t off = t->rn_off, vlen, matched_off; 226 int test, b, rn_b; 227 228 vlen = sizeof (struct sockaddr); 229 230 /* 231 * Open code rn_search(v, top) to avoid overhead of extra 232 * subroutine call. 233 */ 234 for (; t->rn_b >= 0; ) { 235 if (t->rn_bmask & cp[t->rn_off]) 236 t = t->rn_r; 237 else 238 t = t->rn_l; 239 } 240 241 cp += off; 242 cp2 = t->rn_key + off; 243 cplim = v + vlen; 244 for (; cp < cplim; cp++, cp2++) 245 if (*cp != *cp2) 246 goto found_difference_with_key; 247 /* 248 * This extra grot is in case we are explicitly asked 249 * to look up the default. Ugh! 250 * Or 255.255.255.255 251 * 252 * In this case, we have a complete match of the key. Unless 253 * the node is one of the roots, we are finished. 254 * If it is the zeros root, then take what we have, prefering 255 * any real data. 256 * If it is the ones root, then pretend the target key was followed 257 * by a byte of zeros. 258 */ 259 if (!(t->rn_flags & RNF_ROOT)) 260 return (t); /* not a root */ 261 if (t->rn_dupedkey) { 262 t = t->rn_dupedkey; 263 return (t); /* have some real data */ 264 } 265 if (*(cp-1) == 0) 266 return (t); /* not the ones root */ 267 b = 0; /* fake a zero after 255.255.255.255 */ 268 goto calculated_differing_bit; 269 found_difference_with_key: 270 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 271 for (b = 7; (test >>= 1) > 0; ) 272 b--; 273 calculated_differing_bit: 274 matched_off = cp - v; 275 b += matched_off << 3; 276 rn_b = -1 - b; 277 /* 278 * If there is a host route in a duped-key chain, it will be first. 279 */ 280 if ((saved_t = t)->rn_mask == NULL) 281 t = t->rn_dupedkey; 282 for (; t; t = t->rn_dupedkey) { 283 /* 284 * Even if we don't match exactly as a host, 285 * we may match if the leaf we wound up at is 286 * a route to a net. 287 */ 288 if (t->rn_flags & RNF_NORMAL) { 289 if (rn_b <= t->rn_b) 290 return (t); 291 } else if (rn_satisfies_leaf(v, t, matched_off)) { 292 return (t); 293 } 294 } 295 t = saved_t; 296 /* start searching up the tree */ 297 do { 298 struct radix_mask *m; 299 t = t->rn_p; 300 if ((m = t->rn_mklist) != NULL) { 301 /* 302 * If non-contiguous masks ever become important 303 * we can restore the masking and open coding of 304 * the search and satisfaction test and put the 305 * calculation of "off" back before the "do". 306 */ 307 do { 308 if (m->rm_flags & RNF_NORMAL) { 309 if (rn_b <= m->rm_b) 310 return (m->rm_leaf); 311 } else { 312 off = MIN(t->rn_off, matched_off); 313 x = rn_search_m(v, t, m->rm_mask); 314 while (x != NULL && 315 x->rn_mask != m->rm_mask) 316 x = x->rn_dupedkey; 317 if (x != NULL && 318 rn_satisfies_leaf(v, x, off)) 319 return (x); 320 } 321 } while ((m = m->rm_mklist) != NULL); 322 } 323 } while (t != top); 324 return (NULL); 325 } 326 327 #ifdef RN_DEBUG 328 int rn_nodenum; 329 struct radix_node *rn_clist; 330 int rn_saveinfo; 331 boolean_t rn_debug = 1; 332 #endif 333 334 static struct radix_node * 335 rn_newpair(void *v, uint_t b, struct radix_node nodes[2]) 336 { 337 struct radix_node *tt = nodes, *t = tt + 1; 338 339 t->rn_b = b; 340 t->rn_bmask = 0x80 >> (b & 7); 341 t->rn_l = tt; 342 t->rn_off = b >> 3; 343 tt->rn_b = -1; 344 tt->rn_key = v; 345 tt->rn_p = t; 346 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 347 #ifdef RN_DEBUG 348 tt->rn_info = rn_nodenum++; 349 t->rn_info = rn_nodenum++; 350 tt->rn_twin = t; 351 tt->rn_ybro = rn_clist; 352 rn_clist = tt; 353 #endif 354 return (t); 355 } 356 357 static struct radix_node * 358 rn_insert(void* v_arg, struct radix_node_head *head, boolean_t *dupentry, 359 struct radix_node nodes[2]) 360 { 361 uint8_t *v = v_arg; 362 struct radix_node *top = head->rnh_treetop; 363 uint_t head_off = top->rn_off, vlen; 364 struct radix_node *t = rn_search(v_arg, top); 365 uint8_t *cp = v + head_off, b; 366 struct radix_node *tt; 367 368 vlen = sizeof (struct sockaddr); 369 370 /* 371 * Find first bit at which v and t->rn_key differ 372 */ 373 { 374 uint8_t *cp2 = t->rn_key + head_off; 375 uint8_t cmp_res; 376 uint8_t *cplim = v + vlen; 377 378 while (cp < cplim) 379 if (*cp2++ != *cp++) 380 goto found_differing_byte; 381 /* handle adding 255.255.255.255 */ 382 if (!(t->rn_flags & RNF_ROOT) || *(cp2-1) == 0) { 383 *dupentry = _B_TRUE; 384 return (t); 385 } 386 found_differing_byte: 387 *dupentry = _B_FALSE; 388 cmp_res = cp[-1] ^ cp2[-1]; 389 for (b = (cp - v) << 3; cmp_res != 0; b--) 390 cmp_res >>= 1; 391 } 392 { 393 struct radix_node *p, *x = top; 394 cp = v; 395 do { 396 p = x; 397 if (cp[x->rn_off] & x->rn_bmask) 398 x = x->rn_r; 399 else 400 x = x->rn_l; 401 } while (b > (unsigned)x->rn_b); 402 #ifdef RN_DEBUG 403 if (rn_debug) { 404 msglog("rn_insert: Going In:"); 405 traverse(p); 406 } 407 #endif 408 t = rn_newpair(v_arg, b, nodes); 409 tt = t->rn_l; 410 if (!(cp[p->rn_off] & p->rn_bmask)) 411 p->rn_l = t; 412 else 413 p->rn_r = t; 414 x->rn_p = t; /* frees x, p as temp vars below */ 415 t->rn_p = p; 416 if (!(cp[t->rn_off] & t->rn_bmask)) { 417 t->rn_r = x; 418 } else { 419 t->rn_r = tt; 420 t->rn_l = x; 421 } 422 #ifdef RN_DEBUG 423 if (rn_debug) { 424 msglog("rn_insert: Coming Out:"); 425 traverse(p); 426 } 427 #endif 428 } 429 return (tt); 430 } 431 432 static struct radix_node * 433 rn_addmask(void *n_arg, uint_t search, uint_t skip) 434 { 435 uint8_t *netmask = n_arg; 436 struct radix_node *x; 437 uint8_t *cp, *cplim; 438 int b = 0, mlen, j, m0; 439 boolean_t maskduplicated; 440 struct radix_node *saved_x; 441 static int last_zeroed = 0; 442 443 mlen = sizeof (struct sockaddr); 444 if (skip == 0) 445 skip = 1; 446 if (mlen <= skip) 447 return (mask_rnhead->rnh_nodes); 448 if (skip > 1) 449 (void) memmove(addmask_key + 1, rn_ones + 1, skip - 1); 450 if ((m0 = mlen) > skip) 451 (void) memmove(addmask_key + skip, netmask + skip, mlen - skip); 452 /* 453 * Trim trailing zeroes. 454 */ 455 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0; ) 456 cp--; 457 mlen = cp - addmask_key; 458 if (mlen <= skip) { 459 if (m0 >= last_zeroed) 460 last_zeroed = mlen; 461 return (mask_rnhead->rnh_nodes); 462 } 463 if (m0 < last_zeroed) 464 (void) memset(addmask_key + m0, 0, last_zeroed - m0); 465 *addmask_key = last_zeroed = mlen; 466 x = rn_search(addmask_key, rn_masktop); 467 if (memcmp(addmask_key, x->rn_key, mlen) != 0) 468 x = NULL; 469 if (x != NULL || search != 0) 470 return (x); 471 x = rtmalloc(max_keylen + 2*sizeof (*x), "rn_addmask"); 472 saved_x = x; 473 (void) memset(x, 0, max_keylen + 2 * sizeof (*x)); 474 netmask = cp = (uint8_t *)(x + 2); 475 (void) memmove(cp, addmask_key, mlen); 476 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 477 if (maskduplicated) { 478 #ifdef DEBUG 479 logbad(1, "rn_addmask: mask impossibly already in tree"); 480 #else 481 msglog("rn_addmask: mask impossibly already in tree"); 482 #endif 483 free(saved_x); 484 return (x); 485 } 486 /* 487 * Calculate index of mask, and check for normalcy. 488 */ 489 cplim = netmask + mlen; 490 x->rn_flags |= RNF_NORMAL; 491 for (cp = netmask + skip; (cp < cplim) && *cp == 0xff; ) 492 cp++; 493 if (cp != cplim) { 494 for (j = 0x80; (j & *cp) != 0; j >>= 1) 495 b++; 496 if (*cp != (0xFF & ~(0xFF >> b)) || cp != (cplim - 1)) 497 x->rn_flags &= ~RNF_NORMAL; 498 } 499 b += (cp - netmask) << 3; 500 x->rn_b = -1 - b; 501 return (x); 502 } 503 504 static boolean_t /* Note: arbitrary ordering for non-contiguous masks */ 505 rn_lexobetter(void *m_arg, void *n_arg) 506 { 507 uint8_t *mp = m_arg, *np = n_arg, *lim; 508 509 lim = mp + sizeof (struct sockaddr); 510 while (mp < lim) 511 if (*mp++ > *np++) 512 return (_B_TRUE); 513 return (_B_FALSE); 514 } 515 516 static struct radix_mask * 517 rn_new_radix_mask(struct radix_node *tt, 518 struct radix_mask *next) 519 { 520 struct radix_mask *m; 521 522 MKGet(m); 523 if (m == NULL) { 524 #ifdef DEBUG 525 logbad(1, "Mask for route not entered"); 526 #else 527 msglog("Mask for route not entered"); 528 #endif 529 return (NULL); 530 } 531 (void) memset(m, 0, sizeof (*m)); 532 m->rm_b = tt->rn_b; 533 m->rm_flags = tt->rn_flags; 534 if (tt->rn_flags & RNF_NORMAL) 535 m->rm_leaf = tt; 536 else 537 m->rm_mask = tt->rn_mask; 538 m->rm_mklist = next; 539 tt->rn_mklist = m; 540 return (m); 541 } 542 543 static struct radix_node * 544 rn_addroute(void *v_arg, void *n_arg, struct radix_node_head *head, 545 struct radix_node treenodes[2]) 546 { 547 uint8_t *v = v_arg, *netmask = n_arg; 548 struct radix_node *t, *x = 0, *tt; 549 struct radix_node *saved_tt, *top = head->rnh_treetop; 550 short b = 0, b_leaf = 0; 551 boolean_t keyduplicated; 552 uint8_t *mmask; 553 struct radix_mask *m, **mp; 554 555 /* 556 * In dealing with non-contiguous masks, there may be 557 * many different routes which have the same mask. 558 * We will find it useful to have a unique pointer to 559 * the mask to speed avoiding duplicate references at 560 * nodes and possibly save time in calculating indices. 561 */ 562 if (netmask) { 563 if ((x = rn_addmask(netmask, 0, top->rn_off)) == NULL) { 564 DBGMSG(("rn_addroute: addmask failed")); 565 return (NULL); 566 } 567 b_leaf = x->rn_b; 568 b = -1 - x->rn_b; 569 netmask = x->rn_key; 570 } 571 /* 572 * Deal with duplicated keys: attach node to previous instance 573 */ 574 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 575 if (keyduplicated) { 576 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 577 if (tt->rn_mask == netmask) { 578 DBGMSG(("rn_addroute: duplicated route and " 579 "mask")); 580 return (NULL); 581 } 582 if (netmask == NULL || 583 (tt->rn_mask && 584 ((b_leaf < tt->rn_b) || 585 rn_refines(netmask, tt->rn_mask) || 586 rn_lexobetter(netmask, tt->rn_mask)))) 587 break; 588 } 589 /* 590 * If the mask is not duplicated, we wouldn't 591 * find it among possible duplicate key entries 592 * anyway, so the above test doesn't hurt. 593 * 594 * We sort the masks for a duplicated key the same way as 595 * in a masklist -- most specific to least specific. 596 * This may require the unfortunate nuisance of relocating 597 * the head of the list. 598 */ 599 if (tt == saved_tt) { 600 struct radix_node *xx = x; 601 /* link in at head of list */ 602 (tt = treenodes)->rn_dupedkey = t; 603 tt->rn_flags = t->rn_flags; 604 tt->rn_p = x = t->rn_p; 605 if (x->rn_l == t) 606 x->rn_l = tt; 607 else 608 x->rn_r = tt; 609 saved_tt = tt; 610 x = xx; 611 } else { 612 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 613 t->rn_dupedkey = tt; 614 } 615 #ifdef RN_DEBUG 616 t = tt + 1; 617 tt->rn_info = rn_nodenum++; 618 t->rn_info = rn_nodenum++; 619 tt->rn_twin = t; 620 tt->rn_ybro = rn_clist; 621 rn_clist = tt; 622 #endif 623 tt->rn_key = v; 624 tt->rn_b = -1; 625 tt->rn_flags = RNF_ACTIVE; 626 } 627 /* 628 * Put mask in tree. 629 */ 630 if (netmask) { 631 tt->rn_mask = netmask; 632 tt->rn_b = x->rn_b; 633 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 634 } 635 t = saved_tt->rn_p; 636 if (keyduplicated) 637 goto key_already_in_tree; 638 b_leaf = -1 - t->rn_b; 639 if (t->rn_r == saved_tt) 640 x = t->rn_l; 641 else 642 x = t->rn_r; 643 /* Promote general routes from below */ 644 if (x->rn_b < 0) { 645 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 646 if (x->rn_mask != NULL && (x->rn_b >= b_leaf) && 647 x->rn_mklist == NULL) { 648 if ((*mp = m = rn_new_radix_mask(x, 0)) != NULL) 649 mp = &m->rm_mklist; 650 } 651 } else if (x->rn_mklist) { 652 /* 653 * Skip over masks whose index is > that of new node 654 */ 655 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 656 if (m->rm_b >= b_leaf) 657 break; 658 t->rn_mklist = m; 659 *mp = 0; 660 } 661 key_already_in_tree: 662 /* Add new route to highest possible ancestor's list */ 663 if ((netmask == NULL) || (b > t->rn_b)) { 664 return (tt); /* can't lift at all */ 665 } 666 b_leaf = tt->rn_b; 667 do { 668 x = t; 669 t = t->rn_p; 670 } while (b <= t->rn_b && x != top); 671 /* 672 * Search through routes associated with node to 673 * insert new route according to index. 674 * Need same criteria as when sorting dupedkeys to avoid 675 * double loop on deletion. 676 */ 677 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { 678 if (m->rm_b < b_leaf) 679 continue; 680 if (m->rm_b > b_leaf) 681 break; 682 if (m->rm_flags & RNF_NORMAL) { 683 mmask = m->rm_leaf->rn_mask; 684 if (tt->rn_flags & RNF_NORMAL) { 685 #ifdef DEBUG 686 logbad(1, "Non-unique normal route, mask " 687 "not entered"); 688 #else 689 msglog("Non-unique normal route, mask " 690 "not entered"); 691 #endif 692 return (tt); 693 } 694 } else 695 mmask = m->rm_mask; 696 if (mmask == netmask) { 697 m->rm_refs++; 698 tt->rn_mklist = m; 699 return (tt); 700 } 701 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 702 break; 703 } 704 *mp = rn_new_radix_mask(tt, *mp); 705 return (tt); 706 } 707 708 static struct radix_node * 709 rn_delete(void *v_arg, void *netmask_arg, struct radix_node_head *head) 710 { 711 struct radix_node *t, *p, *x, *tt; 712 struct radix_mask *m, *saved_m, **mp; 713 struct radix_node *dupedkey, *saved_tt, *top; 714 uint8_t *v, *netmask; 715 int b; 716 uint_t head_off, vlen; 717 718 v = v_arg; 719 netmask = netmask_arg; 720 x = head->rnh_treetop; 721 tt = rn_search(v, x); 722 head_off = x->rn_off; 723 vlen = sizeof (struct sockaddr); 724 saved_tt = tt; 725 top = x; 726 if (tt == NULL || 727 memcmp(v + head_off, tt->rn_key + head_off, vlen - head_off) != 0) { 728 DBGMSG(("rn_delete: unable to locate route to delete")); 729 return (NULL); 730 } 731 /* 732 * Delete our route from mask lists. 733 */ 734 if (netmask) { 735 if ((x = rn_addmask(netmask, 1, head_off)) == NULL) { 736 DBGMSG(("rn_delete: cannot add mask")); 737 return (NULL); 738 } 739 netmask = x->rn_key; 740 while (tt->rn_mask != netmask) 741 if ((tt = tt->rn_dupedkey) == NULL) { 742 DBGMSG(("rn_delete: cannot locate mask")); 743 return (NULL); 744 } 745 } 746 if (tt->rn_mask == NULL || (saved_m = m = tt->rn_mklist) == NULL) 747 goto annotation_removed; 748 if (tt->rn_flags & RNF_NORMAL) { 749 if (m->rm_leaf != tt || m->rm_refs > 0) { 750 #ifdef DEBUG 751 logbad(1, "rn_delete: inconsistent annotation"); 752 #else 753 msglog("rn_delete: inconsistent annotation"); 754 #endif 755 return (NULL); /* dangling ref could cause disaster */ 756 } 757 } else { 758 if (m->rm_mask != tt->rn_mask) { 759 #ifdef DEBUG 760 logbad(1, "rn_delete: inconsistent annotation"); 761 #else 762 msglog("rn_delete: inconsistent annotation"); 763 #endif 764 goto annotation_removed; 765 } 766 if (--m->rm_refs >= 0) 767 goto annotation_removed; 768 } 769 b = -1 - tt->rn_b; 770 t = saved_tt->rn_p; 771 if (b > t->rn_b) 772 goto annotation_removed; /* Wasn't lifted at all */ 773 do { 774 x = t; 775 t = t->rn_p; 776 } while (b <= t->rn_b && x != top); 777 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 778 if (m == saved_m) { 779 *mp = m->rm_mklist; 780 MKFree(m); 781 break; 782 } 783 if (m == NULL) { 784 #ifdef DEBUG 785 logbad(1, "rn_delete: couldn't find our annotation"); 786 #else 787 msglog("rn_delete: couldn't find our annotation"); 788 #endif 789 if (tt->rn_flags & RNF_NORMAL) 790 return (NULL); /* Dangling ref to us */ 791 } 792 annotation_removed: 793 /* 794 * Eliminate us from tree 795 */ 796 if (tt->rn_flags & RNF_ROOT) { 797 DBGMSG(("rn_delete: cannot delete root")); 798 return (NULL); 799 } 800 #ifdef RN_DEBUG 801 /* Get us out of the creation list */ 802 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 803 if (t != NULL) 804 t->rn_ybro = tt->rn_ybro; 805 #endif 806 t = tt->rn_p; 807 if ((dupedkey = saved_tt->rn_dupedkey) != NULL) { 808 if (tt == saved_tt) { 809 x = dupedkey; 810 x->rn_p = t; 811 if (t->rn_l == tt) 812 t->rn_l = x; 813 else 814 t->rn_r = x; 815 } else { 816 for (x = p = saved_tt; p && p->rn_dupedkey != tt; ) 817 p = p->rn_dupedkey; 818 if (p != NULL) { 819 p->rn_dupedkey = tt->rn_dupedkey; 820 } else { 821 #ifdef DEBUG 822 logbad(1, "rn_delete: couldn't find us"); 823 #else 824 msglog("rn_delete: couldn't find us"); 825 #endif 826 } 827 } 828 t = tt + 1; 829 if (t->rn_flags & RNF_ACTIVE) { 830 #ifndef RN_DEBUG 831 *++x = *t; 832 p = t->rn_p; 833 #else 834 b = t->rn_info; 835 *++x = *t; 836 t->rn_info = b; 837 p = t->rn_p; 838 #endif 839 if (p->rn_l == t) 840 p->rn_l = x; 841 else 842 p->rn_r = x; 843 x->rn_l->rn_p = x; 844 x->rn_r->rn_p = x; 845 } 846 goto out; 847 } 848 if (t->rn_l == tt) 849 x = t->rn_r; 850 else 851 x = t->rn_l; 852 p = t->rn_p; 853 if (p->rn_r == t) 854 p->rn_r = x; 855 else 856 p->rn_l = x; 857 x->rn_p = p; 858 /* 859 * Demote routes attached to us. 860 */ 861 if (t->rn_mklist) { 862 if (x->rn_b >= 0) { 863 for (mp = &x->rn_mklist; (m = *mp) != NULL; ) 864 mp = &m->rm_mklist; 865 *mp = t->rn_mklist; 866 } else { 867 /* 868 * If there are any key,mask pairs in a sibling 869 * duped-key chain, some subset will appear sorted 870 * in the same order attached to our mklist 871 */ 872 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 873 if (m == x->rn_mklist) { 874 struct radix_mask *mm = m->rm_mklist; 875 x->rn_mklist = 0; 876 if (--(m->rm_refs) < 0) 877 MKFree(m); 878 m = mm; 879 } 880 if (m != NULL) { 881 #ifdef DEBUG 882 logbad(1, "rn_delete: Orphaned Mask %p at %p\n", 883 m, x); 884 #else 885 msglog("rn_delete: Orphaned Mask %p at %p\n", m, 886 x); 887 #endif 888 } 889 } 890 } 891 /* 892 * We may be holding an active internal node in the tree. 893 */ 894 x = tt + 1; 895 if (t != x) { 896 #ifndef RN_DEBUG 897 *t = *x; 898 #else 899 b = t->rn_info; 900 *t = *x; 901 t->rn_info = b; 902 #endif 903 t->rn_l->rn_p = t; 904 t->rn_r->rn_p = t; 905 p = x->rn_p; 906 if (p->rn_l == x) 907 p->rn_l = t; 908 else 909 p->rn_r = t; 910 } 911 out: 912 tt->rn_flags &= ~RNF_ACTIVE; 913 tt[1].rn_flags &= ~RNF_ACTIVE; 914 return (tt); 915 } 916 917 int 918 rn_walktree(struct radix_node_head *h, 919 int (*f)(struct radix_node *, void *), 920 void *w) 921 { 922 int error; 923 struct radix_node *base, *next; 924 struct radix_node *rn = h->rnh_treetop; 925 /* 926 * This gets complicated because we may delete the node 927 * while applying the function f to it, so we need to calculate 928 * the successor node in advance. 929 */ 930 /* First time through node, go left */ 931 while (rn->rn_b >= 0) 932 rn = rn->rn_l; 933 do { 934 base = rn; 935 /* If at right child go back up, otherwise, go right */ 936 while (rn->rn_p->rn_r == rn && !(rn->rn_flags & RNF_ROOT)) 937 rn = rn->rn_p; 938 /* Find the next *leaf* since next node might vanish, too */ 939 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0; ) 940 rn = rn->rn_l; 941 next = rn; 942 /* Process leaves */ 943 while ((rn = base) != NULL) { 944 base = rn->rn_dupedkey; 945 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 946 return (error); 947 } 948 rn = next; 949 } while (!(rn->rn_flags & RNF_ROOT)); 950 return (0); 951 } 952 953 int 954 rn_inithead(void **head, uint_t off) 955 { 956 struct radix_node_head *rnh; 957 struct radix_node *t, *tt, *ttt; 958 if (*head) 959 return (1); 960 rnh = rtmalloc(sizeof (*rnh), "rn_inithead"); 961 (void) memset(rnh, 0, sizeof (*rnh)); 962 *head = rnh; 963 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 964 ttt = rnh->rnh_nodes + 2; 965 t->rn_r = ttt; 966 t->rn_p = t; 967 tt = t->rn_l; 968 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 969 tt->rn_b = -1 - off; 970 *ttt = *tt; 971 ttt->rn_key = rn_ones; 972 rnh->rnh_addaddr = rn_addroute; 973 rnh->rnh_deladdr = rn_delete; 974 rnh->rnh_matchaddr = rn_match; 975 rnh->rnh_lookup = rn_lookup; 976 rnh->rnh_walktree = rn_walktree; 977 rnh->rnh_treetop = t; 978 return (1); 979 } 980 981 void 982 rn_init(void) 983 { 984 uint8_t *cp, *cplim; 985 986 if (max_keylen == 0) { 987 logbad(1, "radix functions require max_keylen be set"); 988 return; 989 } 990 rn_zeros = rtmalloc(3 * max_keylen, "rn_init"); 991 (void) memset(rn_zeros, 0, 3 * max_keylen); 992 rn_ones = cp = rn_zeros + max_keylen; 993 addmask_key = cplim = rn_ones + max_keylen; 994 while (cp < cplim) 995 *cp++ = 0xFF; 996 if (rn_inithead((void **)&mask_rnhead, 0) == 0) { 997 logbad(0, "rn_init: could not initialize radix tree"); 998 } 999 } 1000