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 * $FreeBSD: src/sys/net/radix.c,v 1.20.2.3 2002/04/28 05:40:25 suz Exp $ 35 * $DragonFly: src/sys/net/radix.c,v 1.11 2005/03/04 02:21:48 hsu Exp $ 36 */ 37 38 /* 39 * Routines to build and maintain radix trees for routing lookups. 40 */ 41 #include <sys/param.h> 42 #ifdef _KERNEL 43 #include <sys/systm.h> 44 #include <sys/malloc.h> 45 #include <sys/domain.h> 46 #else 47 #include <stdlib.h> 48 #endif 49 #include <sys/syslog.h> 50 #include <net/radix.h> 51 52 /* 53 * The arguments to the radix functions are really counted byte arrays with 54 * the length in the first byte. struct sockaddr's fit this type structurally. 55 */ 56 #define clen(c) (*(u_char *)(c)) 57 58 static int rn_walktree_from(struct radix_node_head *h, char *a, char *m, 59 walktree_f_t *f, void *w); 60 static int rn_walktree(struct radix_node_head *, walktree_f_t *, void *); 61 62 static struct radix_node 63 *rn_insert(char *, struct radix_node_head *, boolean_t *, 64 struct radix_node [2]), 65 *rn_newpair(char *, int, struct radix_node[2]), 66 *rn_search(const char *, struct radix_node *), 67 *rn_search_m(const char *, struct radix_node *, const char *); 68 69 static struct radix_mask *rn_mkfreelist; 70 static struct radix_node_head *mask_rnhead; 71 72 static int max_keylen; 73 static char *rn_zeros, *rn_ones; 74 static char *addmask_key; 75 76 static int rn_lexobetter(char *m, char *n); 77 static struct radix_mask * 78 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *nextmask); 79 static boolean_t 80 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip); 81 82 static __inline struct radix_mask * 83 MKGet(struct radix_mask **l) 84 { 85 struct radix_mask *m; 86 87 if (*l != NULL) { 88 m = *l; 89 *l = m->rm_next; 90 } else { 91 R_Malloc(m, struct radix_mask *, sizeof *m); 92 } 93 return m; 94 } 95 96 static __inline void 97 MKFree(struct radix_mask **l, struct radix_mask *m) 98 { 99 m->rm_next = *l; 100 *l = m; 101 } 102 103 /* 104 * The data structure for the keys is a radix tree with one way 105 * branching removed. The index rn_bit at an internal node n represents a bit 106 * position to be tested. The tree is arranged so that all descendants 107 * of a node n have keys whose bits all agree up to position rn_bit - 1. 108 * (We say the index of n is rn_bit.) 109 * 110 * There is at least one descendant which has a one bit at position rn_bit, 111 * and at least one with a zero there. 112 * 113 * A route is determined by a pair of key and mask. We require that the 114 * bit-wise logical and of the key and mask to be the key. 115 * We define the index of a route to associated with the mask to be 116 * the first bit number in the mask where 0 occurs (with bit number 0 117 * representing the highest order bit). 118 * 119 * We say a mask is normal if every bit is 0, past the index of the mask. 120 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit, 121 * and m is a normal mask, then the route applies to every descendant of n. 122 * If the index(m) < rn_bit, this implies the trailing last few bits of k 123 * before bit b are all 0, (and hence consequently true of every descendant 124 * of n), so the route applies to all descendants of the node as well. 125 * 126 * Similar logic shows that a non-normal mask m such that 127 * index(m) <= index(n) could potentially apply to many children of n. 128 * Thus, for each non-host route, we attach its mask to a list at an internal 129 * node as high in the tree as we can go. 130 * 131 * The present version of the code makes use of normal routes in short- 132 * circuiting an explict mask and compare operation when testing whether 133 * a key satisfies a normal route, and also in remembering the unique leaf 134 * that governs a subtree. 135 */ 136 137 static struct radix_node * 138 rn_search(const char *v, struct radix_node *head) 139 { 140 struct radix_node *x; 141 142 x = head; 143 while (x->rn_bit >= 0) { 144 if (x->rn_bmask & v[x->rn_offset]) 145 x = x->rn_right; 146 else 147 x = x->rn_left; 148 } 149 return (x); 150 } 151 152 static struct radix_node * 153 rn_search_m(const char *v, struct radix_node *head, const char *m) 154 { 155 struct radix_node *x; 156 157 for (x = head; x->rn_bit >= 0;) { 158 if ((x->rn_bmask & m[x->rn_offset]) && 159 (x->rn_bmask & v[x->rn_offset])) 160 x = x->rn_right; 161 else 162 x = x->rn_left; 163 } 164 return x; 165 } 166 167 boolean_t 168 rn_refines(char *m, char *n) 169 { 170 char *lim, *lim2; 171 int longer = clen(n++) - clen(m++); 172 boolean_t masks_are_equal = TRUE; 173 174 lim2 = lim = n + clen(n); 175 if (longer > 0) 176 lim -= longer; 177 while (n < lim) { 178 if (*n & ~(*m)) 179 return FALSE; 180 if (*n++ != *m++) 181 masks_are_equal = FALSE; 182 } 183 while (n < lim2) 184 if (*n++) 185 return FALSE; 186 if (masks_are_equal && (longer < 0)) 187 for (lim2 = m - longer; m < lim2; ) 188 if (*m++) 189 return TRUE; 190 return (!masks_are_equal); 191 } 192 193 struct radix_node * 194 rn_lookup(char *key, char *mask, struct radix_node_head *head) 195 { 196 struct radix_node *x; 197 char *netmask = NULL; 198 199 if (mask != NULL) { 200 x = rn_addmask(mask, TRUE, head->rnh_treetop->rn_offset); 201 if (x == NULL) 202 return (NULL); 203 netmask = x->rn_key; 204 } 205 x = rn_match(key, head); 206 if (x != NULL && netmask != NULL) { 207 while (x != NULL && x->rn_mask != netmask) 208 x = x->rn_dupedkey; 209 } 210 return x; 211 } 212 213 static boolean_t 214 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip) 215 { 216 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 217 char *cplim; 218 int length = min(clen(cp), clen(cp2)); 219 220 if (cp3 == NULL) 221 cp3 = rn_ones; 222 else 223 length = min(length, clen(cp3)); 224 cplim = cp + length; 225 cp3 += skip; 226 cp2 += skip; 227 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 228 if ((*cp ^ *cp2) & *cp3) 229 return FALSE; 230 return TRUE; 231 } 232 233 struct radix_node * 234 rn_match(char *key, struct radix_node_head *head) 235 { 236 struct radix_node *t, *x; 237 char *cp = key, *cp2; 238 char *cplim; 239 struct radix_node *saved_t, *top = head->rnh_treetop; 240 int off = top->rn_offset, klen, matched_off; 241 int test, b, rn_bit; 242 243 t = rn_search(key, top); 244 /* 245 * See if we match exactly as a host destination 246 * or at least learn how many bits match, for normal mask finesse. 247 * 248 * It doesn't hurt us to limit how many bytes to check 249 * to the length of the mask, since if it matches we had a genuine 250 * match and the leaf we have is the most specific one anyway; 251 * if it didn't match with a shorter length it would fail 252 * with a long one. This wins big for class B&C netmasks which 253 * are probably the most common case... 254 */ 255 if (t->rn_mask != NULL) 256 klen = clen(t->rn_mask); 257 else 258 klen = clen(key); 259 cp += off; cp2 = t->rn_key + off; cplim = key + klen; 260 for (; cp < cplim; cp++, cp2++) 261 if (*cp != *cp2) 262 goto on1; 263 /* 264 * This extra grot is in case we are explicitly asked 265 * to look up the default. Ugh! 266 * 267 * Never return the root node itself, it seems to cause a 268 * lot of confusion. 269 */ 270 if (t->rn_flags & RNF_ROOT) 271 t = t->rn_dupedkey; 272 return t; 273 on1: 274 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 275 for (b = 7; (test >>= 1) > 0;) 276 b--; 277 matched_off = cp - key; 278 b += matched_off << 3; 279 rn_bit = -1 - b; 280 /* 281 * If there is a host route in a duped-key chain, it will be first. 282 */ 283 if ((saved_t = t)->rn_mask == NULL) 284 t = t->rn_dupedkey; 285 for (; t; t = t->rn_dupedkey) { 286 /* 287 * Even if we don't match exactly as a host, 288 * we may match if the leaf we wound up at is 289 * a route to a net. 290 */ 291 if (t->rn_flags & RNF_NORMAL) { 292 if (rn_bit <= t->rn_bit) 293 return t; 294 } else if (rn_satisfies_leaf(key, t, matched_off)) 295 return t; 296 } 297 t = saved_t; 298 /* start searching up the tree */ 299 do { 300 struct radix_mask *m; 301 302 t = t->rn_parent; 303 /* 304 * If non-contiguous masks ever become important 305 * we can restore the masking and open coding of 306 * the search and satisfaction test and put the 307 * calculation of "off" back before the "do". 308 */ 309 m = t->rn_mklist; 310 while (m != NULL) { 311 if (m->rm_flags & RNF_NORMAL) { 312 if (rn_bit <= m->rm_bit) 313 return (m->rm_leaf); 314 } else { 315 off = min(t->rn_offset, matched_off); 316 x = rn_search_m(key, t, m->rm_mask); 317 while (x != NULL && x->rn_mask != m->rm_mask) 318 x = x->rn_dupedkey; 319 if (x && rn_satisfies_leaf(key, x, off)) 320 return x; 321 } 322 m = m->rm_next; 323 } 324 } while (t != top); 325 return NULL; 326 } 327 328 #ifdef RN_DEBUG 329 int rn_nodenum; 330 struct radix_node *rn_clist; 331 int rn_saveinfo; 332 boolean_t rn_debug = TRUE; 333 #endif 334 335 static struct radix_node * 336 rn_newpair(char *key, int indexbit, struct radix_node nodes[2]) 337 { 338 struct radix_node *leaf = &nodes[0], *interior = &nodes[1]; 339 340 interior->rn_bit = indexbit; 341 interior->rn_bmask = 0x80 >> (indexbit & 0x7); 342 interior->rn_offset = indexbit >> 3; 343 interior->rn_left = leaf; 344 interior->rn_mklist = NULL; 345 346 leaf->rn_bit = -1; 347 leaf->rn_key = key; 348 leaf->rn_parent = interior; 349 leaf->rn_flags = interior->rn_flags = RNF_ACTIVE; 350 leaf->rn_mklist = NULL; 351 352 #ifdef RN_DEBUG 353 leaf->rn_info = rn_nodenum++; 354 interior->rn_info = rn_nodenum++; 355 leaf->rn_twin = interior; 356 leaf->rn_ybro = rn_clist; 357 rn_clist = leaf; 358 #endif 359 return interior; 360 } 361 362 static struct radix_node * 363 rn_insert(char *key, struct radix_node_head *head, boolean_t *dupentry, 364 struct radix_node nodes[2]) 365 { 366 struct radix_node *top = head->rnh_treetop; 367 int head_off = top->rn_offset, klen = clen(key); 368 struct radix_node *t = rn_search(key, top); 369 char *cp = key + head_off; 370 int b; 371 struct radix_node *tt; 372 373 /* 374 * Find first bit at which the key and t->rn_key differ 375 */ 376 { 377 char *cp2 = t->rn_key + head_off; 378 int cmp_res; 379 char *cplim = key + klen; 380 381 while (cp < cplim) 382 if (*cp2++ != *cp++) 383 goto on1; 384 *dupentry = TRUE; 385 return t; 386 on1: 387 *dupentry = FALSE; 388 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 389 for (b = (cp - key) << 3; cmp_res; b--) 390 cmp_res >>= 1; 391 } 392 { 393 struct radix_node *p, *x = top; 394 395 cp = key; 396 do { 397 p = x; 398 if (cp[x->rn_offset] & x->rn_bmask) 399 x = x->rn_right; 400 else 401 x = x->rn_left; 402 } while (b > (unsigned) x->rn_bit); 403 /* x->rn_bit < b && x->rn_bit >= 0 */ 404 #ifdef RN_DEBUG 405 if (rn_debug) 406 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 407 #endif 408 t = rn_newpair(key, b, nodes); 409 tt = t->rn_left; 410 if ((cp[p->rn_offset] & p->rn_bmask) == 0) 411 p->rn_left = t; 412 else 413 p->rn_right = t; 414 x->rn_parent = t; 415 t->rn_parent = p; /* frees x, p as temp vars below */ 416 if ((cp[t->rn_offset] & t->rn_bmask) == 0) { 417 t->rn_right = x; 418 } else { 419 t->rn_right = tt; 420 t->rn_left = x; 421 } 422 #ifdef RN_DEBUG 423 if (rn_debug) 424 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 425 #endif 426 } 427 return (tt); 428 } 429 430 struct radix_node * 431 rn_addmask(char *netmask, boolean_t search, int skip) 432 { 433 struct radix_node *x, *saved_x; 434 char *cp, *cplim; 435 int b = 0, mlen, m0, j; 436 boolean_t maskduplicated, isnormal; 437 static int last_zeroed = 0; 438 439 if ((mlen = clen(netmask)) > max_keylen) 440 mlen = max_keylen; 441 if (skip == 0) 442 skip = 1; 443 if (mlen <= skip) 444 return (mask_rnhead->rnh_nodes); 445 if (skip > 1) 446 bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 447 if ((m0 = mlen) > skip) 448 bcopy(netmask + skip, addmask_key + skip, mlen - skip); 449 /* 450 * Trim trailing zeroes. 451 */ 452 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 453 cp--; 454 mlen = cp - addmask_key; 455 if (mlen <= skip) { 456 if (m0 >= last_zeroed) 457 last_zeroed = mlen; 458 return (mask_rnhead->rnh_nodes); 459 } 460 if (m0 < last_zeroed) 461 bzero(addmask_key + m0, last_zeroed - m0); 462 *addmask_key = last_zeroed = mlen; 463 x = rn_search(addmask_key, mask_rnhead->rnh_treetop); 464 if (bcmp(addmask_key, x->rn_key, mlen) != 0) 465 x = NULL; 466 if (x != NULL || search) 467 return (x); 468 R_Malloc(x, struct radix_node *, max_keylen + 2 * (sizeof *x)); 469 if ((saved_x = x) == NULL) 470 return (NULL); 471 bzero(x, max_keylen + 2 * (sizeof *x)); 472 netmask = cp = (char *)(x + 2); 473 bcopy(addmask_key, cp, mlen); 474 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 475 if (maskduplicated) { 476 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 477 Free(saved_x); 478 return (x); 479 } 480 /* 481 * Calculate index of mask, and check for normalcy. 482 */ 483 isnormal = TRUE; 484 cplim = netmask + mlen; 485 for (cp = netmask + skip; cp < cplim && clen(cp) == 0xff;) 486 cp++; 487 if (cp != cplim) { 488 static const char normal_chars[] = { 489 0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1 490 }; 491 492 for (j = 0x80; (j & *cp) != 0; j >>= 1) 493 b++; 494 if (*cp != normal_chars[b] || cp != (cplim - 1)) 495 isnormal = FALSE; 496 } 497 b += (cp - netmask) << 3; 498 x->rn_bit = -1 - b; 499 if (isnormal) 500 x->rn_flags |= RNF_NORMAL; 501 return (x); 502 } 503 504 static boolean_t /* XXX: arbitrary ordering for non-contiguous masks */ 505 rn_lexobetter(char *mp, char *np) 506 { 507 char *lim; 508 509 if ((unsigned) *mp > (unsigned) *np) 510 return TRUE;/* not really, but need to check longer one first */ 511 if (*mp == *np) 512 for (lim = mp + clen(mp); mp < lim;) 513 if (*mp++ > *np++) 514 return TRUE; 515 return FALSE; 516 } 517 518 static struct radix_mask * 519 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *nextmask) 520 { 521 struct radix_mask *m; 522 523 m = MKGet(&rn_mkfreelist); 524 if (m == NULL) { 525 log(LOG_ERR, "Mask for route not entered\n"); 526 return (NULL); 527 } 528 bzero(m, sizeof *m); 529 m->rm_bit = tt->rn_bit; 530 m->rm_flags = tt->rn_flags; 531 if (tt->rn_flags & RNF_NORMAL) 532 m->rm_leaf = tt; 533 else 534 m->rm_mask = tt->rn_mask; 535 m->rm_next = nextmask; 536 tt->rn_mklist = m; 537 return m; 538 } 539 540 struct radix_node * 541 rn_addroute(char *key, char *netmask, struct radix_node_head *head, 542 struct radix_node treenodes[2]) 543 { 544 struct radix_node *t, *x = NULL, *tt; 545 struct radix_node *saved_tt, *top = head->rnh_treetop; 546 short b = 0, b_leaf = 0; 547 boolean_t keyduplicated; 548 char *mmask; 549 struct radix_mask *m, **mp; 550 551 /* 552 * In dealing with non-contiguous masks, there may be 553 * many different routes which have the same mask. 554 * We will find it useful to have a unique pointer to 555 * the mask to speed avoiding duplicate references at 556 * nodes and possibly save time in calculating indices. 557 */ 558 if (netmask != NULL) { 559 if ((x = rn_addmask(netmask, FALSE, top->rn_offset)) == NULL) 560 return (NULL); 561 b_leaf = x->rn_bit; 562 b = -1 - x->rn_bit; 563 netmask = x->rn_key; 564 } 565 /* 566 * Deal with duplicated keys: attach node to previous instance 567 */ 568 saved_tt = tt = rn_insert(key, head, &keyduplicated, treenodes); 569 if (keyduplicated) { 570 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 571 if (tt->rn_mask == netmask) 572 return (NULL); 573 if (netmask == NULL || 574 (tt->rn_mask && 575 ((b_leaf < tt->rn_bit) /* index(netmask) > node */ 576 || rn_refines(netmask, tt->rn_mask) 577 || rn_lexobetter(netmask, tt->rn_mask)))) 578 break; 579 } 580 /* 581 * If the mask is not duplicated, we wouldn't 582 * find it among possible duplicate key entries 583 * anyway, so the above test doesn't hurt. 584 * 585 * We sort the masks for a duplicated key the same way as 586 * in a masklist -- most specific to least specific. 587 * This may require the unfortunate nuisance of relocating 588 * the head of the list. 589 */ 590 if (tt == saved_tt) { 591 struct radix_node *xx = x; 592 /* link in at head of list */ 593 (tt = treenodes)->rn_dupedkey = t; 594 tt->rn_flags = t->rn_flags; 595 tt->rn_parent = x = t->rn_parent; 596 t->rn_parent = tt; /* parent */ 597 if (x->rn_left == t) 598 x->rn_left = tt; 599 else 600 x->rn_right = tt; 601 saved_tt = tt; x = xx; 602 } else { 603 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 604 t->rn_dupedkey = tt; 605 tt->rn_parent = t; /* parent */ 606 if (tt->rn_dupedkey != NULL) /* parent */ 607 tt->rn_dupedkey->rn_parent = tt; /* parent */ 608 } 609 #ifdef RN_DEBUG 610 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 611 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 612 #endif 613 tt->rn_key = key; 614 tt->rn_bit = -1; 615 tt->rn_flags = RNF_ACTIVE; 616 } 617 /* 618 * Put mask in tree. 619 */ 620 if (netmask != NULL) { 621 tt->rn_mask = netmask; 622 tt->rn_bit = x->rn_bit; 623 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 624 } 625 t = saved_tt->rn_parent; 626 if (keyduplicated) 627 goto on2; 628 b_leaf = -1 - t->rn_bit; 629 if (t->rn_right == saved_tt) 630 x = t->rn_left; 631 else 632 x = t->rn_right; 633 /* Promote general routes from below */ 634 if (x->rn_bit < 0) { 635 mp = &t->rn_mklist; 636 while (x != NULL) { 637 if (x->rn_mask != NULL && 638 x->rn_bit >= b_leaf && 639 x->rn_mklist == NULL) { 640 *mp = m = rn_new_radix_mask(x, NULL); 641 if (m != NULL) 642 mp = &m->rm_next; 643 } 644 x = x->rn_dupedkey; 645 } 646 } else if (x->rn_mklist != NULL) { 647 /* 648 * Skip over masks whose index is > that of new node 649 */ 650 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) 651 if (m->rm_bit >= b_leaf) 652 break; 653 t->rn_mklist = m; 654 *mp = NULL; 655 } 656 on2: 657 /* Add new route to highest possible ancestor's list */ 658 if ((netmask == NULL) || (b > t->rn_bit )) 659 return tt; /* can't lift at all */ 660 b_leaf = tt->rn_bit; 661 do { 662 x = t; 663 t = t->rn_parent; 664 } while (b <= t->rn_bit && x != top); 665 /* 666 * Search through routes associated with node to 667 * insert new route according to index. 668 * Need same criteria as when sorting dupedkeys to avoid 669 * double loop on deletion. 670 */ 671 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) { 672 if (m->rm_bit < b_leaf) 673 continue; 674 if (m->rm_bit > b_leaf) 675 break; 676 if (m->rm_flags & RNF_NORMAL) { 677 mmask = m->rm_leaf->rn_mask; 678 if (tt->rn_flags & RNF_NORMAL) { 679 log(LOG_ERR, 680 "Non-unique normal route, mask not entered\n"); 681 return tt; 682 } 683 } else 684 mmask = m->rm_mask; 685 if (mmask == netmask) { 686 m->rm_refs++; 687 tt->rn_mklist = m; 688 return tt; 689 } 690 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 691 break; 692 } 693 *mp = rn_new_radix_mask(tt, *mp); 694 return tt; 695 } 696 697 struct radix_node * 698 rn_delete(char *key, char *netmask, struct radix_node_head *head) 699 { 700 struct radix_node *t, *p, *x, *tt; 701 struct radix_mask *m, *saved_m, **mp; 702 struct radix_node *dupedkey, *saved_tt, *top; 703 int b, head_off, klen; 704 705 x = head->rnh_treetop; 706 tt = rn_search(key, x); 707 head_off = x->rn_offset; 708 klen = clen(key); 709 saved_tt = tt; 710 top = x; 711 if (tt == NULL || 712 bcmp(key + head_off, tt->rn_key + head_off, klen - head_off)) 713 return (NULL); 714 /* 715 * Delete our route from mask lists. 716 */ 717 if (netmask != NULL) { 718 if ((x = rn_addmask(netmask, TRUE, head_off)) == NULL) 719 return (NULL); 720 netmask = x->rn_key; 721 while (tt->rn_mask != netmask) 722 if ((tt = tt->rn_dupedkey) == NULL) 723 return (NULL); 724 } 725 if (tt->rn_mask == NULL || (saved_m = m = tt->rn_mklist) == NULL) 726 goto on1; 727 if (tt->rn_flags & RNF_NORMAL) { 728 if (m->rm_leaf != tt || m->rm_refs > 0) { 729 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 730 return (NULL); /* dangling ref could cause disaster */ 731 } 732 } else { 733 if (m->rm_mask != tt->rn_mask) { 734 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 735 goto on1; 736 } 737 if (--m->rm_refs >= 0) 738 goto on1; 739 } 740 b = -1 - tt->rn_bit; 741 t = saved_tt->rn_parent; 742 if (b > t->rn_bit) 743 goto on1; /* Wasn't lifted at all */ 744 do { 745 x = t; 746 t = t->rn_parent; 747 } while (b <= t->rn_bit && x != top); 748 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) 749 if (m == saved_m) { 750 *mp = m->rm_next; 751 MKFree(&rn_mkfreelist, m); 752 break; 753 } 754 if (m == NULL) { 755 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 756 if (tt->rn_flags & RNF_NORMAL) 757 return (NULL); /* Dangling ref to us */ 758 } 759 on1: 760 /* 761 * Eliminate us from tree 762 */ 763 if (tt->rn_flags & RNF_ROOT) 764 return (NULL); 765 #ifdef RN_DEBUG 766 /* Get us out of the creation list */ 767 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 768 if (t) t->rn_ybro = tt->rn_ybro; 769 #endif 770 t = tt->rn_parent; 771 dupedkey = saved_tt->rn_dupedkey; 772 if (dupedkey != NULL) { 773 /* 774 * at this point, tt is the deletion target and saved_tt 775 * is the head of the dupekey chain 776 */ 777 if (tt == saved_tt) { 778 /* remove from head of chain */ 779 x = dupedkey; x->rn_parent = t; 780 if (t->rn_left == tt) 781 t->rn_left = x; 782 else 783 t->rn_right = x; 784 } else { 785 /* find node in front of tt on the chain */ 786 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 787 p = p->rn_dupedkey; 788 if (p) { 789 p->rn_dupedkey = tt->rn_dupedkey; 790 if (tt->rn_dupedkey) /* parent */ 791 tt->rn_dupedkey->rn_parent = p; 792 /* parent */ 793 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 794 } 795 t = tt + 1; 796 if (t->rn_flags & RNF_ACTIVE) { 797 #ifndef RN_DEBUG 798 *++x = *t; 799 p = t->rn_parent; 800 #else 801 b = t->rn_info; 802 *++x = *t; 803 t->rn_info = b; 804 p = t->rn_parent; 805 #endif 806 if (p->rn_left == t) 807 p->rn_left = x; 808 else 809 p->rn_right = x; 810 x->rn_left->rn_parent = x; 811 x->rn_right->rn_parent = x; 812 } 813 goto out; 814 } 815 if (t->rn_left == tt) 816 x = t->rn_right; 817 else 818 x = t->rn_left; 819 p = t->rn_parent; 820 if (p->rn_right == t) 821 p->rn_right = x; 822 else 823 p->rn_left = x; 824 x->rn_parent = p; 825 /* 826 * Demote routes attached to us. 827 */ 828 if (t->rn_mklist != NULL) { 829 if (x->rn_bit >= 0) { 830 for (mp = &x->rn_mklist; (m = *mp);) 831 mp = &m->rm_next; 832 *mp = t->rn_mklist; 833 } else { 834 /* 835 * If there are any (key, mask) pairs in a sibling 836 * duped-key chain, some subset will appear sorted 837 * in the same order attached to our mklist. 838 */ 839 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 840 if (m == x->rn_mklist) { 841 struct radix_mask *mm = m->rm_next; 842 843 x->rn_mklist = NULL; 844 if (--(m->rm_refs) < 0) 845 MKFree(&rn_mkfreelist, m); 846 m = mm; 847 } 848 if (m) 849 log(LOG_ERR, 850 "rn_delete: Orphaned Mask %p at %p\n", 851 (void *)m, (void *)x); 852 } 853 } 854 /* 855 * We may be holding an active internal node in the tree. 856 */ 857 x = tt + 1; 858 if (t != x) { 859 #ifndef RN_DEBUG 860 *t = *x; 861 #else 862 b = t->rn_info; 863 *t = *x; 864 t->rn_info = b; 865 #endif 866 t->rn_left->rn_parent = t; 867 t->rn_right->rn_parent = t; 868 p = x->rn_parent; 869 if (p->rn_left == x) 870 p->rn_left = t; 871 else 872 p->rn_right = t; 873 } 874 out: 875 tt->rn_flags &= ~RNF_ACTIVE; 876 tt[1].rn_flags &= ~RNF_ACTIVE; 877 return (tt); 878 } 879 880 /* 881 * This is the same as rn_walktree() except for the parameters and the 882 * exit. 883 */ 884 static int 885 rn_walktree_from(struct radix_node_head *h, char *xa, char *xm, 886 walktree_f_t *f, void *w) 887 { 888 struct radix_node *base, *next; 889 struct radix_node *rn, *last = NULL /* shut up gcc */; 890 boolean_t stopping = FALSE; 891 int lastb, error; 892 893 /* 894 * rn_search_m is sort-of-open-coded here. 895 */ 896 /* printf("about to search\n"); */ 897 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) { 898 last = rn; 899 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n", 900 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */ 901 if (!(rn->rn_bmask & xm[rn->rn_offset])) { 902 break; 903 } 904 if (rn->rn_bmask & xa[rn->rn_offset]) { 905 rn = rn->rn_right; 906 } else { 907 rn = rn->rn_left; 908 } 909 } 910 /* printf("done searching\n"); */ 911 912 /* 913 * Two cases: either we stepped off the end of our mask, 914 * in which case last == rn, or we reached a leaf, in which 915 * case we want to start from the last node we looked at. 916 * Either way, last is the node we want to start from. 917 */ 918 rn = last; 919 lastb = rn->rn_bit; 920 921 /* printf("rn %p, lastb %d\n", rn, lastb);*/ 922 923 /* 924 * This gets complicated because we may delete the node 925 * while applying the function f to it, so we need to calculate 926 * the successor node in advance. 927 */ 928 while (rn->rn_bit >= 0) 929 rn = rn->rn_left; 930 931 while (!stopping) { 932 /* printf("node %p (%d)\n", rn, rn->rn_bit); */ 933 base = rn; 934 /* If at right child go back up, otherwise, go right */ 935 while (rn->rn_parent->rn_right == rn && 936 !(rn->rn_flags & RNF_ROOT)) { 937 rn = rn->rn_parent; 938 939 /* if went up beyond last, stop */ 940 if (rn->rn_bit < lastb) { 941 stopping = TRUE; 942 /* printf("up too far\n"); */ 943 } 944 } 945 946 /* Find the next *leaf* since next node might vanish, too */ 947 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 948 rn = rn->rn_left; 949 next = rn; 950 /* Process leaves */ 951 while ((rn = base) != NULL) { 952 base = rn->rn_dupedkey; 953 /* printf("leaf %p\n", rn); */ 954 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 955 return (error); 956 } 957 rn = next; 958 959 if (rn->rn_flags & RNF_ROOT) { 960 /* printf("root, stopping"); */ 961 stopping = TRUE; 962 } 963 964 } 965 return 0; 966 } 967 968 static int 969 rn_walktree(struct radix_node_head *h, walktree_f_t *f, void *w) 970 { 971 struct radix_node *base, *next; 972 struct radix_node *rn = h->rnh_treetop; 973 int error; 974 975 /* 976 * This gets complicated because we may delete the node 977 * while applying the function f to it, so we need to calculate 978 * the successor node in advance. 979 */ 980 /* First time through node, go left */ 981 while (rn->rn_bit >= 0) 982 rn = rn->rn_left; 983 for (;;) { 984 base = rn; 985 /* If at right child go back up, otherwise, go right */ 986 while (rn->rn_parent->rn_right == rn && 987 !(rn->rn_flags & RNF_ROOT)) 988 rn = rn->rn_parent; 989 /* Find the next *leaf* since next node might vanish, too */ 990 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 991 rn = rn->rn_left; 992 next = rn; 993 /* Process leaves */ 994 while ((rn = base)) { 995 base = rn->rn_dupedkey; 996 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 997 return (error); 998 } 999 rn = next; 1000 if (rn->rn_flags & RNF_ROOT) 1001 return (0); 1002 } 1003 /* NOTREACHED */ 1004 } 1005 1006 int 1007 rn_inithead(void **head, int off) 1008 { 1009 struct radix_node_head *rnh; 1010 struct radix_node *root, *left, *right; 1011 1012 if (*head != NULL) /* already initialized */ 1013 return (1); 1014 1015 R_Malloc(rnh, struct radix_node_head *, sizeof *rnh); 1016 if (rnh == NULL) 1017 return (0); 1018 bzero(rnh, sizeof *rnh); 1019 *head = rnh; 1020 1021 root = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1022 right = &rnh->rnh_nodes[2]; 1023 root->rn_parent = root; 1024 root->rn_flags = RNF_ROOT | RNF_ACTIVE; 1025 root->rn_right = right; 1026 1027 left = root->rn_left; 1028 left->rn_bit = -1 - off; 1029 left->rn_flags = RNF_ROOT | RNF_ACTIVE; 1030 1031 *right = *left; 1032 right->rn_key = rn_ones; 1033 1034 rnh->rnh_treetop = root; 1035 1036 rnh->rnh_addaddr = rn_addroute; 1037 rnh->rnh_deladdr = rn_delete; 1038 rnh->rnh_matchaddr = rn_match; 1039 rnh->rnh_lookup = rn_lookup; 1040 rnh->rnh_walktree = rn_walktree; 1041 rnh->rnh_walktree_from = rn_walktree_from; 1042 1043 return (1); 1044 } 1045 1046 void 1047 rn_init() 1048 { 1049 char *cp, *cplim; 1050 #ifdef _KERNEL 1051 struct domain *dom; 1052 1053 SLIST_FOREACH(dom, &domains, dom_next) 1054 if (dom->dom_maxrtkey > max_keylen) 1055 max_keylen = dom->dom_maxrtkey; 1056 #endif 1057 if (max_keylen == 0) { 1058 log(LOG_ERR, 1059 "rn_init: radix functions require max_keylen be set\n"); 1060 return; 1061 } 1062 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1063 if (rn_zeros == NULL) 1064 panic("rn_init"); 1065 bzero(rn_zeros, 3 * max_keylen); 1066 rn_ones = cp = rn_zeros + max_keylen; 1067 addmask_key = cplim = rn_ones + max_keylen; 1068 while (cp < cplim) 1069 *cp++ = -1; 1070 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 1071 panic("rn_init 2"); 1072 } 1073