radix.c revision 1.38
1/* $NetBSD: radix.c,v 1.38 2007/07/12 04:28:59 dyoung Exp $ */ 2 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 * @(#)radix.c 8.6 (Berkeley) 10/17/95 32 */ 33 34/* 35 * Routines to build and maintain radix trees for routing lookups. 36 */ 37 38#include <sys/cdefs.h> 39__KERNEL_RCSID(0, "$NetBSD: radix.c,v 1.38 2007/07/12 04:28:59 dyoung Exp $"); 40 41#ifndef _NET_RADIX_H_ 42#include <sys/param.h> 43#ifdef _KERNEL 44#include "opt_inet.h" 45 46#include <sys/systm.h> 47#include <sys/malloc.h> 48#define M_DONTWAIT M_NOWAIT 49#include <sys/domain.h> 50#include <netinet/ip_encap.h> 51#else 52#include <stdlib.h> 53#endif 54#include <machine/stdarg.h> 55#include <sys/syslog.h> 56#include <net/radix.h> 57#endif 58 59typedef void (*rn_printer_t)(void *, const char *fmt, ...); 60 61int max_keylen; 62struct radix_mask *rn_mkfreelist; 63struct radix_node_head *mask_rnhead; 64static char *addmask_key; 65static const char normal_chars[] = 66 {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 67static char *rn_zeros, *rn_ones; 68 69#define rn_masktop (mask_rnhead->rnh_treetop) 70 71static int rn_satisfies_leaf(const char *, struct radix_node *, int); 72static int rn_lexobetter(const void *, const void *); 73static struct radix_mask *rn_new_radix_mask(struct radix_node *, 74 struct radix_mask *); 75static struct radix_node *rn_walknext(struct radix_node *, rn_printer_t, 76 void *); 77static struct radix_node *rn_walkfirst(struct radix_node *, rn_printer_t, 78 void *); 79static void rn_nodeprint(struct radix_node *, rn_printer_t, void *, 80 const char *); 81 82#define SUBTREE_OPEN "[ " 83#define SUBTREE_CLOSE " ]" 84 85#ifdef RN_DEBUG 86static void rn_treeprint(struct radix_node_head *, rn_printer_t, void *); 87#endif /* RN_DEBUG */ 88 89/* 90 * The data structure for the keys is a radix tree with one way 91 * branching removed. The index rn_b at an internal node n represents a bit 92 * position to be tested. The tree is arranged so that all descendants 93 * of a node n have keys whose bits all agree up to position rn_b - 1. 94 * (We say the index of n is rn_b.) 95 * 96 * There is at least one descendant which has a one bit at position rn_b, 97 * and at least one with a zero there. 98 * 99 * A route is determined by a pair of key and mask. We require that the 100 * bit-wise logical and of the key and mask to be the key. 101 * We define the index of a route to associated with the mask to be 102 * the first bit number in the mask where 0 occurs (with bit number 0 103 * representing the highest order bit). 104 * 105 * We say a mask is normal if every bit is 0, past the index of the mask. 106 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 107 * and m is a normal mask, then the route applies to every descendant of n. 108 * If the index(m) < rn_b, this implies the trailing last few bits of k 109 * before bit b are all 0, (and hence consequently true of every descendant 110 * of n), so the route applies to all descendants of the node as well. 111 * 112 * Similar logic shows that a non-normal mask m such that 113 * index(m) <= index(n) could potentially apply to many children of n. 114 * Thus, for each non-host route, we attach its mask to a list at an internal 115 * node as high in the tree as we can go. 116 * 117 * The present version of the code makes use of normal routes in short- 118 * circuiting an explicit mask and compare operation when testing whether 119 * a key satisfies a normal route, and also in remembering the unique leaf 120 * that governs a subtree. 121 */ 122 123struct radix_node * 124rn_search( 125 const void *v_arg, 126 struct radix_node *head) 127{ 128 const u_char * const v = v_arg; 129 struct radix_node *x; 130 131 for (x = head; x->rn_b >= 0;) { 132 if (x->rn_bmask & v[x->rn_off]) 133 x = x->rn_r; 134 else 135 x = x->rn_l; 136 } 137 return x; 138} 139 140struct radix_node * 141rn_search_m( 142 const void *v_arg, 143 struct radix_node *head, 144 const void *m_arg) 145{ 146 struct radix_node *x; 147 const u_char * const v = v_arg; 148 const u_char * const m = m_arg; 149 150 for (x = head; x->rn_b >= 0;) { 151 if ((x->rn_bmask & m[x->rn_off]) && 152 (x->rn_bmask & v[x->rn_off])) 153 x = x->rn_r; 154 else 155 x = x->rn_l; 156 } 157 return x; 158} 159 160int 161rn_refines( 162 const void *m_arg, 163 const void *n_arg) 164{ 165 const char *m = m_arg; 166 const char *n = n_arg; 167 const char *lim = n + *(const u_char *)n; 168 const char *lim2 = lim; 169 int longer = (*(const u_char *)n++) - (int)(*(const u_char *)m++); 170 int masks_are_equal = 1; 171 172 if (longer > 0) 173 lim -= longer; 174 while (n < lim) { 175 if (*n & ~(*m)) 176 return 0; 177 if (*n++ != *m++) 178 masks_are_equal = 0; 179 } 180 while (n < lim2) 181 if (*n++) 182 return 0; 183 if (masks_are_equal && (longer < 0)) 184 for (lim2 = m - longer; m < lim2; ) 185 if (*m++) 186 return 1; 187 return !masks_are_equal; 188} 189 190struct radix_node * 191rn_lookup( 192 const void *v_arg, 193 const void *m_arg, 194 struct radix_node_head *head) 195{ 196 struct radix_node *x; 197 const char *netmask = NULL; 198 199 if (m_arg) { 200 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 201 return NULL; 202 netmask = x->rn_key; 203 } 204 x = rn_match(v_arg, head); 205 if (x != NULL && netmask != NULL) { 206 while (x != NULL && x->rn_mask != netmask) 207 x = x->rn_dupedkey; 208 } 209 return x; 210} 211 212static int 213rn_satisfies_leaf( 214 const char *trial, 215 struct radix_node *leaf, 216 int skip) 217{ 218 const char *cp = trial; 219 const char *cp2 = leaf->rn_key; 220 const char *cp3 = leaf->rn_mask; 221 const char *cplim; 222 int length = min(*(const u_char *)cp, *(const u_char *)cp2); 223 224 if (cp3 == 0) 225 cp3 = rn_ones; 226 else 227 length = min(length, *(const u_char *)cp3); 228 cplim = cp + length; cp3 += skip; cp2 += skip; 229 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 230 if ((*cp ^ *cp2) & *cp3) 231 return 0; 232 return 1; 233} 234 235struct radix_node * 236rn_match( 237 const void *v_arg, 238 struct radix_node_head *head) 239{ 240 const char * const v = v_arg; 241 struct radix_node *t = head->rnh_treetop; 242 struct radix_node *top = t; 243 struct radix_node *x; 244 struct radix_node *saved_t; 245 const char *cp = v; 246 const char *cp2; 247 const char *cplim; 248 int off = t->rn_off; 249 int vlen = *(const u_char *)cp; 250 int matched_off; 251 int test, b, rn_b; 252 253 /* 254 * Open code rn_search(v, top) to avoid overhead of extra 255 * subroutine call. 256 */ 257 for (; t->rn_b >= 0; ) { 258 if (t->rn_bmask & cp[t->rn_off]) 259 t = t->rn_r; 260 else 261 t = t->rn_l; 262 } 263 /* 264 * See if we match exactly as a host destination 265 * or at least learn how many bits match, for normal mask finesse. 266 * 267 * It doesn't hurt us to limit how many bytes to check 268 * to the length of the mask, since if it matches we had a genuine 269 * match and the leaf we have is the most specific one anyway; 270 * if it didn't match with a shorter length it would fail 271 * with a long one. This wins big for class B&C netmasks which 272 * are probably the most common case... 273 */ 274 if (t->rn_mask) 275 vlen = *(const u_char *)t->rn_mask; 276 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 277 for (; cp < cplim; cp++, cp2++) 278 if (*cp != *cp2) 279 goto on1; 280 /* 281 * This extra grot is in case we are explicitly asked 282 * to look up the default. Ugh! 283 */ 284 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 285 t = t->rn_dupedkey; 286 return t; 287on1: 288 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 289 for (b = 7; (test >>= 1) > 0;) 290 b--; 291 matched_off = cp - v; 292 b += matched_off << 3; 293 rn_b = -1 - b; 294 /* 295 * If there is a host route in a duped-key chain, it will be first. 296 */ 297 if ((saved_t = t)->rn_mask == 0) 298 t = t->rn_dupedkey; 299 for (; t; t = t->rn_dupedkey) 300 /* 301 * Even if we don't match exactly as a host, 302 * we may match if the leaf we wound up at is 303 * a route to a net. 304 */ 305 if (t->rn_flags & RNF_NORMAL) { 306 if (rn_b <= t->rn_b) 307 return t; 308 } else if (rn_satisfies_leaf(v, t, matched_off)) 309 return t; 310 t = saved_t; 311 /* start searching up the tree */ 312 do { 313 struct radix_mask *m; 314 t = t->rn_p; 315 m = t->rn_mklist; 316 if (m) { 317 /* 318 * If non-contiguous masks ever become important 319 * we can restore the masking and open coding of 320 * the search and satisfaction test and put the 321 * calculation of "off" back before the "do". 322 */ 323 do { 324 if (m->rm_flags & RNF_NORMAL) { 325 if (rn_b <= m->rm_b) 326 return m->rm_leaf; 327 } else { 328 off = min(t->rn_off, matched_off); 329 x = rn_search_m(v, t, m->rm_mask); 330 while (x && x->rn_mask != m->rm_mask) 331 x = x->rn_dupedkey; 332 if (x && rn_satisfies_leaf(v, x, off)) 333 return x; 334 } 335 m = m->rm_mklist; 336 } while (m); 337 } 338 } while (t != top); 339 return NULL; 340} 341 342static void 343rn_nodeprint(struct radix_node *rn, rn_printer_t printer, void *arg, 344 const char *delim) 345{ 346 (*printer)(arg, "%s(%s%p: p<%p> l<%p> r<%p>)", 347 delim, ((void *)rn == arg) ? "*" : "", rn, rn->rn_p, 348 rn->rn_l, rn->rn_r); 349} 350 351#ifdef RN_DEBUG 352int rn_debug = 1; 353 354static void 355rn_dbg_print(void *arg, const char *fmt, ...) 356{ 357 va_list ap; 358 359 va_start(ap, fmt); 360 vlog(LOG_DEBUG, fmt, ap); 361 va_end(ap); 362} 363 364static void 365rn_treeprint(struct radix_node_head *h, rn_printer_t printer, void *arg) 366{ 367 struct radix_node *dup, *rn; 368 const char *delim; 369 370 if (printer == NULL) 371 return; 372 373 rn = rn_walkfirst(h->rnh_treetop, printer, arg); 374 for (;;) { 375 /* Process leaves */ 376 delim = ""; 377 for (dup = rn; dup != NULL; dup = dup->rn_dupedkey) { 378 if ((dup->rn_flags & RNF_ROOT) != 0) 379 continue; 380 rn_nodeprint(dup, printer, arg, delim); 381 delim = ", "; 382 } 383 rn = rn_walknext(rn, printer, arg); 384 if (rn->rn_flags & RNF_ROOT) 385 return; 386 } 387 /* NOTREACHED */ 388} 389 390#define traverse(__head, __rn) rn_treeprint((__head), rn_dbg_print, (__rn)) 391#endif /* RN_DEBUG */ 392 393struct radix_node * 394rn_newpair( 395 const void *v, 396 int b, 397 struct radix_node nodes[2]) 398{ 399 struct radix_node *tt = nodes; 400 struct radix_node *t = tt + 1; 401 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 402 t->rn_l = tt; t->rn_off = b >> 3; 403 tt->rn_b = -1; tt->rn_key = v; tt->rn_p = t; 404 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 405 return t; 406} 407 408struct radix_node * 409rn_insert( 410 const void *v_arg, 411 struct radix_node_head *head, 412 int *dupentry, 413 struct radix_node nodes[2]) 414{ 415 struct radix_node *top = head->rnh_treetop; 416 struct radix_node *t = rn_search(v_arg, top); 417 struct radix_node *tt; 418 const char *v = v_arg; 419 int head_off = top->rn_off; 420 int vlen = *((const u_char *)v); 421 const char *cp = v + head_off; 422 int b; 423 /* 424 * Find first bit at which v and t->rn_key differ 425 */ 426 { 427 const char *cp2 = t->rn_key + head_off; 428 const char *cplim = v + vlen; 429 int cmp_res; 430 431 while (cp < cplim) 432 if (*cp2++ != *cp++) 433 goto on1; 434 *dupentry = 1; 435 return t; 436on1: 437 *dupentry = 0; 438 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 439 for (b = (cp - v) << 3; cmp_res; b--) 440 cmp_res >>= 1; 441 } 442 { 443 struct radix_node *p, *x = top; 444 cp = v; 445 do { 446 p = x; 447 if (cp[x->rn_off] & x->rn_bmask) 448 x = x->rn_r; 449 else x = x->rn_l; 450 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 451#ifdef RN_DEBUG 452 if (rn_debug) 453 log(LOG_DEBUG, "%s: Going In:\n", __func__), traverse(head, p); 454#endif 455 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 456 if ((cp[p->rn_off] & p->rn_bmask) == 0) 457 p->rn_l = t; 458 else 459 p->rn_r = t; 460 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 461 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 462 t->rn_r = x; 463 } else { 464 t->rn_r = tt; t->rn_l = x; 465 } 466#ifdef RN_DEBUG 467 if (rn_debug) { 468 log(LOG_DEBUG, "%s: Coming Out:\n", __func__), 469 traverse(head, p); 470 } 471#endif /* RN_DEBUG */ 472 } 473 return tt; 474} 475 476struct radix_node * 477rn_addmask( 478 const void *n_arg, 479 int search, 480 int skip) 481{ 482 const char *netmask = n_arg; 483 const char *cp; 484 const char *cplim; 485 struct radix_node *x; 486 struct radix_node *saved_x; 487 int b = 0, mlen, j; 488 int maskduplicated, m0, isnormal; 489 static int last_zeroed = 0; 490 491 if ((mlen = *(const u_char *)netmask) > max_keylen) 492 mlen = max_keylen; 493 if (skip == 0) 494 skip = 1; 495 if (mlen <= skip) 496 return mask_rnhead->rnh_nodes; 497 if (skip > 1) 498 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 499 if ((m0 = mlen) > skip) 500 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 501 /* 502 * Trim trailing zeroes. 503 */ 504 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 505 cp--; 506 mlen = cp - addmask_key; 507 if (mlen <= skip) { 508 if (m0 >= last_zeroed) 509 last_zeroed = mlen; 510 return mask_rnhead->rnh_nodes; 511 } 512 if (m0 < last_zeroed) 513 Bzero(addmask_key + m0, last_zeroed - m0); 514 *addmask_key = last_zeroed = mlen; 515 x = rn_search(addmask_key, rn_masktop); 516 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 517 x = 0; 518 if (x || search) 519 return x; 520 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 521 if ((saved_x = x) == NULL) 522 return NULL; 523 Bzero(x, max_keylen + 2 * sizeof (*x)); 524 cp = netmask = (void *)(x + 2); 525 Bcopy(addmask_key, (void *)(x + 2), mlen); 526 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 527 if (maskduplicated) { 528 log(LOG_ERR, "rn_addmask: mask impossibly already in tree\n"); 529 Free(saved_x); 530 return x; 531 } 532 /* 533 * Calculate index of mask, and check for normalcy. 534 */ 535 cplim = netmask + mlen; isnormal = 1; 536 for (cp = netmask + skip; (cp < cplim) && *(const u_char *)cp == 0xff;) 537 cp++; 538 if (cp != cplim) { 539 for (j = 0x80; (j & *cp) != 0; j >>= 1) 540 b++; 541 if (*cp != normal_chars[b] || cp != (cplim - 1)) 542 isnormal = 0; 543 } 544 b += (cp - netmask) << 3; 545 x->rn_b = -1 - b; 546 if (isnormal) 547 x->rn_flags |= RNF_NORMAL; 548 return x; 549} 550 551static int /* XXX: arbitrary ordering for non-contiguous masks */ 552rn_lexobetter( 553 const void *m_arg, 554 const void *n_arg) 555{ 556 const u_char *mp = m_arg; 557 const u_char *np = n_arg; 558 const u_char *lim; 559 560 if (*mp > *np) 561 return 1; /* not really, but need to check longer one first */ 562 if (*mp == *np) 563 for (lim = mp + *mp; mp < lim;) 564 if (*mp++ > *np++) 565 return 1; 566 return 0; 567} 568 569static struct radix_mask * 570rn_new_radix_mask( 571 struct radix_node *tt, 572 struct radix_mask *next) 573{ 574 struct radix_mask *m; 575 576 MKGet(m); 577 if (m == NULL) { 578 log(LOG_ERR, "Mask for route not entered\n"); 579 return NULL; 580 } 581 Bzero(m, sizeof *m); 582 m->rm_b = tt->rn_b; 583 m->rm_flags = tt->rn_flags; 584 if (tt->rn_flags & RNF_NORMAL) 585 m->rm_leaf = tt; 586 else 587 m->rm_mask = tt->rn_mask; 588 m->rm_mklist = next; 589 tt->rn_mklist = m; 590 return m; 591} 592 593struct radix_node * 594rn_addroute( 595 const void *v_arg, 596 const void *n_arg, 597 struct radix_node_head *head, 598 struct radix_node treenodes[2]) 599{ 600 const char *v = v_arg, *netmask = n_arg; 601 struct radix_node *t, *x = NULL, *tt; 602 struct radix_node *saved_tt, *top = head->rnh_treetop; 603 short b = 0, b_leaf = 0; 604 int keyduplicated; 605 const char *mmask; 606 struct radix_mask *m, **mp; 607 608 /* 609 * In dealing with non-contiguous masks, there may be 610 * many different routes which have the same mask. 611 * We will find it useful to have a unique pointer to 612 * the mask to speed avoiding duplicate references at 613 * nodes and possibly save time in calculating indices. 614 */ 615 if (netmask != NULL) { 616 if ((x = rn_addmask(netmask, 0, top->rn_off)) == NULL) 617 return NULL; 618 b_leaf = x->rn_b; 619 b = -1 - x->rn_b; 620 netmask = x->rn_key; 621 } 622 /* 623 * Deal with duplicated keys: attach node to previous instance 624 */ 625 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 626 if (keyduplicated) { 627 for (t = tt; tt != NULL; t = tt, tt = tt->rn_dupedkey) { 628 if (tt->rn_mask == netmask) 629 return NULL; 630 if (netmask == NULL || 631 (tt->rn_mask != NULL && 632 (b_leaf < tt->rn_b || /* index(netmask) > node */ 633 rn_refines(netmask, tt->rn_mask) || 634 rn_lexobetter(netmask, tt->rn_mask)))) 635 break; 636 } 637 /* 638 * If the mask is not duplicated, we wouldn't 639 * find it among possible duplicate key entries 640 * anyway, so the above test doesn't hurt. 641 * 642 * We sort the masks for a duplicated key the same way as 643 * in a masklist -- most specific to least specific. 644 * This may require the unfortunate nuisance of relocating 645 * the head of the list. 646 * 647 * We also reverse, or doubly link the list through the 648 * parent pointer. 649 */ 650 if (tt == saved_tt) { 651 struct radix_node *xx = x; 652 /* link in at head of list */ 653 (tt = treenodes)->rn_dupedkey = t; 654 tt->rn_flags = t->rn_flags; 655 tt->rn_p = x = t->rn_p; 656 t->rn_p = tt; 657 if (x->rn_l == t) 658 x->rn_l = tt; 659 else 660 x->rn_r = tt; 661 saved_tt = tt; 662 x = xx; 663 } else { 664 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 665 t->rn_dupedkey = tt; 666 tt->rn_p = t; 667 if (tt->rn_dupedkey) 668 tt->rn_dupedkey->rn_p = tt; 669 } 670 tt->rn_key = v; 671 tt->rn_b = -1; 672 tt->rn_flags = RNF_ACTIVE; 673 } 674 /* 675 * Put mask in tree. 676 */ 677 if (netmask != NULL) { 678 tt->rn_mask = netmask; 679 tt->rn_b = x->rn_b; 680 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 681 } 682 t = saved_tt->rn_p; 683 if (keyduplicated) 684 goto on2; 685 b_leaf = -1 - t->rn_b; 686 if (t->rn_r == saved_tt) 687 x = t->rn_l; 688 else 689 x = t->rn_r; 690 /* Promote general routes from below */ 691 if (x->rn_b < 0) { 692 for (mp = &t->rn_mklist; x != NULL; x = x->rn_dupedkey) { 693 if (x->rn_mask != NULL && x->rn_b >= b_leaf && 694 x->rn_mklist == NULL) { 695 *mp = m = rn_new_radix_mask(x, NULL); 696 if (m != NULL) 697 mp = &m->rm_mklist; 698 } 699 } 700 } else if (x->rn_mklist != NULL) { 701 /* 702 * Skip over masks whose index is > that of new node 703 */ 704 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 705 if (m->rm_b >= b_leaf) 706 break; 707 t->rn_mklist = m; 708 *mp = NULL; 709 } 710on2: 711 /* Add new route to highest possible ancestor's list */ 712 if (netmask == NULL || b > t->rn_b) 713 return tt; /* can't lift at all */ 714 b_leaf = tt->rn_b; 715 do { 716 x = t; 717 t = t->rn_p; 718 } while (b <= t->rn_b && x != top); 719 /* 720 * Search through routes associated with node to 721 * insert new route according to index. 722 * Need same criteria as when sorting dupedkeys to avoid 723 * double loop on deletion. 724 */ 725 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { 726 if (m->rm_b < b_leaf) 727 continue; 728 if (m->rm_b > b_leaf) 729 break; 730 if (m->rm_flags & RNF_NORMAL) { 731 mmask = m->rm_leaf->rn_mask; 732 if (tt->rn_flags & RNF_NORMAL) { 733 log(LOG_ERR, "Non-unique normal route," 734 " mask not entered\n"); 735 return tt; 736 } 737 } else 738 mmask = m->rm_mask; 739 if (mmask == netmask) { 740 m->rm_refs++; 741 tt->rn_mklist = m; 742 return tt; 743 } 744 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 745 break; 746 } 747 *mp = rn_new_radix_mask(tt, *mp); 748 return tt; 749} 750 751struct radix_node * 752rn_delete1( 753 const void *v_arg, 754 const void *netmask_arg, 755 struct radix_node_head *head, 756 struct radix_node *rn) 757{ 758 struct radix_node *t, *p, *x, *tt; 759 struct radix_mask *m, *saved_m, **mp; 760 struct radix_node *dupedkey, *saved_tt, *top; 761 const char *v, *netmask; 762 int b, head_off, vlen; 763 764 v = v_arg; 765 netmask = netmask_arg; 766 x = head->rnh_treetop; 767 tt = rn_search(v, x); 768 head_off = x->rn_off; 769 vlen = *(const u_char *)v; 770 saved_tt = tt; 771 top = x; 772 if (tt == NULL || 773 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 774 return NULL; 775 /* 776 * Delete our route from mask lists. 777 */ 778 if (netmask != NULL) { 779 if ((x = rn_addmask(netmask, 1, head_off)) == NULL) 780 return NULL; 781 netmask = x->rn_key; 782 while (tt->rn_mask != netmask) 783 if ((tt = tt->rn_dupedkey) == NULL) 784 return NULL; 785 } 786 if (tt->rn_mask == NULL || (saved_m = m = tt->rn_mklist) == NULL) 787 goto on1; 788 if (tt->rn_flags & RNF_NORMAL) { 789 if (m->rm_leaf != tt || m->rm_refs > 0) { 790 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 791 return NULL; /* dangling ref could cause disaster */ 792 } 793 } else { 794 if (m->rm_mask != tt->rn_mask) { 795 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 796 goto on1; 797 } 798 if (--m->rm_refs >= 0) 799 goto on1; 800 } 801 b = -1 - tt->rn_b; 802 t = saved_tt->rn_p; 803 if (b > t->rn_b) 804 goto on1; /* Wasn't lifted at all */ 805 do { 806 x = t; 807 t = t->rn_p; 808 } while (b <= t->rn_b && x != top); 809 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { 810 if (m == saved_m) { 811 *mp = m->rm_mklist; 812 MKFree(m); 813 break; 814 } 815 } 816 if (m == NULL) { 817 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 818 if (tt->rn_flags & RNF_NORMAL) 819 return NULL; /* Dangling ref to us */ 820 } 821on1: 822 /* 823 * Eliminate us from tree 824 */ 825 if (tt->rn_flags & RNF_ROOT) 826 return NULL; 827#ifdef RN_DEBUG 828 if (rn_debug) 829 log(LOG_DEBUG, "%s: Going In:\n", __func__), traverse(head, tt); 830#endif 831 t = tt->rn_p; 832 dupedkey = saved_tt->rn_dupedkey; 833 if (dupedkey != NULL) { 834 /* 835 * Here, tt is the deletion target, and 836 * saved_tt is the head of the dupedkey chain. 837 */ 838 if (tt == saved_tt) { 839 x = dupedkey; 840 x->rn_p = t; 841 if (t->rn_l == tt) 842 t->rn_l = x; 843 else 844 t->rn_r = x; 845 } else { 846 /* find node in front of tt on the chain */ 847 for (x = p = saved_tt; 848 p != NULL && p->rn_dupedkey != tt;) 849 p = p->rn_dupedkey; 850 if (p != NULL) { 851 p->rn_dupedkey = tt->rn_dupedkey; 852 if (tt->rn_dupedkey != NULL) 853 tt->rn_dupedkey->rn_p = p; 854 } else 855 log(LOG_ERR, "rn_delete: couldn't find us\n"); 856 } 857 t = tt + 1; 858 if (t->rn_flags & RNF_ACTIVE) { 859 *++x = *t; 860 p = t->rn_p; 861 if (p->rn_l == t) 862 p->rn_l = x; 863 else 864 p->rn_r = x; 865 x->rn_l->rn_p = x; 866 x->rn_r->rn_p = x; 867 } 868 goto out; 869 } 870 if (t->rn_l == tt) 871 x = t->rn_r; 872 else 873 x = t->rn_l; 874 p = t->rn_p; 875 if (p->rn_r == t) 876 p->rn_r = x; 877 else 878 p->rn_l = x; 879 x->rn_p = p; 880 /* 881 * Demote routes attached to us. 882 */ 883 if (t->rn_mklist == NULL) 884 ; 885 else if (x->rn_b >= 0) { 886 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 887 ; 888 *mp = t->rn_mklist; 889 } else { 890 /* If there are any key,mask pairs in a sibling 891 duped-key chain, some subset will appear sorted 892 in the same order attached to our mklist */ 893 for (m = t->rn_mklist; 894 m != NULL && x != NULL; 895 x = x->rn_dupedkey) { 896 if (m == x->rn_mklist) { 897 struct radix_mask *mm = m->rm_mklist; 898 x->rn_mklist = NULL; 899 if (--(m->rm_refs) < 0) 900 MKFree(m); 901 m = mm; 902 } 903 } 904 if (m != NULL) { 905 log(LOG_ERR, "rn_delete: Orphaned Mask %p at %p\n", 906 m, x); 907 } 908 } 909 /* 910 * We may be holding an active internal node in the tree. 911 */ 912 x = tt + 1; 913 if (t != x) { 914 *t = *x; 915 t->rn_l->rn_p = t; 916 t->rn_r->rn_p = t; 917 p = x->rn_p; 918 if (p->rn_l == x) 919 p->rn_l = t; 920 else 921 p->rn_r = t; 922 } 923out: 924#ifdef RN_DEBUG 925 if (rn_debug) { 926 log(LOG_DEBUG, "%s: Coming Out:\n", __func__), 927 traverse(head, tt); 928 } 929#endif /* RN_DEBUG */ 930 tt->rn_flags &= ~RNF_ACTIVE; 931 tt[1].rn_flags &= ~RNF_ACTIVE; 932 return tt; 933} 934 935struct radix_node * 936rn_delete( 937 const void *v_arg, 938 const void *netmask_arg, 939 struct radix_node_head *head) 940{ 941 return rn_delete1(v_arg, netmask_arg, head, NULL); 942} 943 944static struct radix_node * 945rn_walknext(struct radix_node *rn, rn_printer_t printer, void *arg) 946{ 947 /* If at right child go back up, otherwise, go right */ 948 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) { 949 if (printer != NULL) 950 (*printer)(arg, SUBTREE_CLOSE); 951 rn = rn->rn_p; 952 } 953 if (printer) 954 rn_nodeprint(rn->rn_p, printer, arg, ""); 955 /* Find the next *leaf* since next node might vanish, too */ 956 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) { 957 if (printer != NULL) 958 (*printer)(arg, SUBTREE_OPEN); 959 rn = rn->rn_l; 960 } 961 return rn; 962} 963 964static struct radix_node * 965rn_walkfirst(struct radix_node *rn, rn_printer_t printer, void *arg) 966{ 967 /* First time through node, go left */ 968 while (rn->rn_b >= 0) { 969 if (printer != NULL) 970 (*printer)(arg, SUBTREE_OPEN); 971 rn = rn->rn_l; 972 } 973 return rn; 974} 975 976int 977rn_walktree( 978 struct radix_node_head *h, 979 int (*f)(struct radix_node *, void *), 980 void *w) 981{ 982 int error; 983 struct radix_node *base, *next, *rn; 984 /* 985 * This gets complicated because we may delete the node 986 * while applying the function f to it, so we need to calculate 987 * the successor node in advance. 988 */ 989 rn = rn_walkfirst(h->rnh_treetop, NULL, NULL); 990 for (;;) { 991 base = rn; 992 next = rn_walknext(rn, NULL, NULL); 993 /* Process leaves */ 994 while ((rn = base) != NULL) { 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 1006int 1007rn_inithead(head, off) 1008 void **head; 1009 int off; 1010{ 1011 struct radix_node_head *rnh; 1012 1013 if (*head != NULL) 1014 return 1; 1015 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 1016 if (rnh == NULL) 1017 return 0; 1018 *head = rnh; 1019 return rn_inithead0(rnh, off); 1020} 1021 1022int 1023rn_inithead0(rnh, off) 1024 struct radix_node_head *rnh; 1025 int off; 1026{ 1027 struct radix_node *t; 1028 struct radix_node *tt; 1029 struct radix_node *ttt; 1030 1031 Bzero(rnh, sizeof (*rnh)); 1032 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1033 ttt = rnh->rnh_nodes + 2; 1034 t->rn_r = ttt; 1035 t->rn_p = t; 1036 tt = t->rn_l; 1037 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 1038 tt->rn_b = -1 - off; 1039 *ttt = *tt; 1040 ttt->rn_key = rn_ones; 1041 rnh->rnh_addaddr = rn_addroute; 1042 rnh->rnh_deladdr = rn_delete; 1043 rnh->rnh_matchaddr = rn_match; 1044 rnh->rnh_lookup = rn_lookup; 1045 rnh->rnh_treetop = t; 1046 return 1; 1047} 1048 1049void 1050rn_init() 1051{ 1052 char *cp, *cplim; 1053#ifdef _KERNEL 1054 static int initialized; 1055 __link_set_decl(domains, struct domain); 1056 struct domain *const *dpp; 1057 1058 if (initialized) 1059 return; 1060 initialized = 1; 1061 1062 __link_set_foreach(dpp, domains) { 1063 if ((*dpp)->dom_maxrtkey > max_keylen) 1064 max_keylen = (*dpp)->dom_maxrtkey; 1065 } 1066#ifdef INET 1067 encap_setkeylen(); 1068#endif 1069#endif 1070 if (max_keylen == 0) { 1071 log(LOG_ERR, 1072 "rn_init: radix functions require max_keylen be set\n"); 1073 return; 1074 } 1075 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1076 if (rn_zeros == NULL) 1077 panic("rn_init"); 1078 Bzero(rn_zeros, 3 * max_keylen); 1079 rn_ones = cp = rn_zeros + max_keylen; 1080 addmask_key = cplim = rn_ones + max_keylen; 1081 while (cp < cplim) 1082 *cp++ = -1; 1083 if (rn_inithead((void *)&mask_rnhead, 0) == 0) 1084 panic("rn_init 2"); 1085} 1086