1 /* $OpenBSD: radix.c,v 1.30 2012/07/10 15:53:34 blambert Exp $ */ 2 /* $NetBSD: radix.c,v 1.20 2003/08/07 16:32:56 agc Exp $ */ 3 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. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)radix.c 8.6 (Berkeley) 10/17/95 33 */ 34 35 /* 36 * Routines to build and maintain radix trees for routing lookups. 37 */ 38 39 #ifndef _NET_RADIX_H_ 40 #include <sys/param.h> 41 #ifdef _KERNEL 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #define M_DONTWAIT M_NOWAIT 45 #include <sys/domain.h> 46 #else 47 #include <stdlib.h> 48 #endif 49 #include <sys/syslog.h> 50 #include <net/radix.h> 51 #endif 52 53 #ifndef SMALL_KERNEL 54 #include <sys/socket.h> 55 #include <net/route.h> 56 #include <net/radix_mpath.h> 57 #endif 58 59 int max_keylen; 60 struct radix_mask *rn_mkfreelist; 61 struct radix_node_head *mask_rnhead; 62 static char *addmask_key; 63 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 64 static char *rn_zeros, *rn_ones; 65 66 #define rn_masktop (mask_rnhead->rnh_treetop) 67 #undef Bcmp 68 #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 69 70 static int rn_satisfies_leaf(char *, struct radix_node *, int); 71 static int rn_lexobetter(void *, void *); 72 static struct radix_mask *rn_new_radix_mask(struct radix_node *, 73 struct radix_mask *); 74 75 struct radix_node *rn_insert(void *, struct radix_node_head *, int *, 76 struct radix_node [2]); 77 struct radix_node *rn_newpair(void *, int, struct radix_node[2]); 78 struct radix_node *rn_search(void *, struct radix_node *); 79 struct radix_node *rn_search_m(void *, struct radix_node *, void *); 80 81 /* 82 * The data structure for the keys is a radix tree with one way 83 * branching removed. The index rn_b at an internal node n represents a bit 84 * position to be tested. The tree is arranged so that all descendants 85 * of a node n have keys whose bits all agree up to position rn_b - 1. 86 * (We say the index of n is rn_b.) 87 * 88 * There is at least one descendant which has a one bit at position rn_b, 89 * and at least one with a zero there. 90 * 91 * A route is determined by a pair of key and mask. We require that the 92 * bit-wise logical and of the key and mask to be the key. 93 * We define the index of a route to associated with the mask to be 94 * the first bit number in the mask where 0 occurs (with bit number 0 95 * representing the highest order bit). 96 * 97 * We say a mask is normal if every bit is 0, past the index of the mask. 98 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 99 * and m is a normal mask, then the route applies to every descendant of n. 100 * If the index(m) < rn_b, this implies the trailing last few bits of k 101 * before bit b are all 0, (and hence consequently true of every descendant 102 * of n), so the route applies to all descendants of the node as well. 103 * 104 * Similar logic shows that a non-normal mask m such that 105 * index(m) <= index(n) could potentially apply to many children of n. 106 * Thus, for each non-host route, we attach its mask to a list at an internal 107 * node as high in the tree as we can go. 108 * 109 * The present version of the code makes use of normal routes in short- 110 * circuiting an explicit mask and compare operation when testing whether 111 * a key satisfies a normal route, and also in remembering the unique leaf 112 * that governs a subtree. 113 */ 114 115 struct radix_node * 116 rn_search(void *v_arg, struct radix_node *head) 117 { 118 struct radix_node *x; 119 caddr_t v; 120 121 for (x = head, v = v_arg; x->rn_b >= 0;) { 122 if (x->rn_bmask & v[x->rn_off]) 123 x = x->rn_r; 124 else 125 x = x->rn_l; 126 } 127 return (x); 128 } 129 130 struct radix_node * 131 rn_search_m(void *v_arg, struct radix_node *head, void *m_arg) 132 { 133 struct radix_node *x; 134 caddr_t v = v_arg, m = m_arg; 135 136 for (x = head; x->rn_b >= 0;) { 137 if ((x->rn_bmask & m[x->rn_off]) && 138 (x->rn_bmask & v[x->rn_off])) 139 x = x->rn_r; 140 else 141 x = x->rn_l; 142 } 143 return x; 144 } 145 146 int 147 rn_refines(void *m_arg, void *n_arg) 148 { 149 caddr_t m = m_arg, n = n_arg; 150 caddr_t lim, lim2 = lim = n + *(u_char *)n; 151 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 152 int masks_are_equal = 1; 153 154 if (longer > 0) 155 lim -= longer; 156 while (n < lim) { 157 if (*n & ~(*m)) 158 return 0; 159 if (*n++ != *m++) 160 masks_are_equal = 0; 161 } 162 while (n < lim2) 163 if (*n++) 164 return 0; 165 if (masks_are_equal && (longer < 0)) 166 for (lim2 = m - longer; m < lim2; ) 167 if (*m++) 168 return 1; 169 return (!masks_are_equal); 170 } 171 172 struct radix_node * 173 rn_lookup(void *v_arg, void *m_arg, struct radix_node_head *head) 174 { 175 struct radix_node *x; 176 caddr_t netmask = 0; 177 178 if (m_arg) { 179 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 180 return (0); 181 netmask = x->rn_key; 182 } 183 x = rn_match(v_arg, head); 184 if (x && netmask) { 185 while (x && x->rn_mask != netmask) 186 x = x->rn_dupedkey; 187 } 188 return x; 189 } 190 191 static int 192 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip) 193 { 194 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 195 char *cplim; 196 int length = min(*(u_char *)cp, *(u_char *)cp2); 197 198 if (cp3 == 0) 199 cp3 = rn_ones; 200 else 201 length = min(length, *(u_char *)cp3); 202 cplim = cp + length; cp3 += skip; cp2 += skip; 203 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 204 if ((*cp ^ *cp2) & *cp3) 205 return 0; 206 return 1; 207 } 208 209 struct radix_node * 210 rn_match(void *v_arg, struct radix_node_head *head) 211 { 212 caddr_t v = v_arg; 213 struct radix_node *t = head->rnh_treetop, *x; 214 caddr_t cp = v, cp2; 215 caddr_t cplim; 216 struct radix_node *saved_t, *top = t; 217 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 218 int test, b, rn_b; 219 220 /* 221 * Open code rn_search(v, top) to avoid overhead of extra 222 * subroutine call. 223 */ 224 for (; t->rn_b >= 0; ) { 225 if (t->rn_bmask & cp[t->rn_off]) 226 t = t->rn_r; 227 else 228 t = t->rn_l; 229 } 230 /* 231 * See if we match exactly as a host destination 232 * or at least learn how many bits match, for normal mask finesse. 233 * 234 * It doesn't hurt us to limit how many bytes to check 235 * to the length of the mask, since if it matches we had a genuine 236 * match and the leaf we have is the most specific one anyway; 237 * if it didn't match with a shorter length it would fail 238 * with a long one. This wins big for class B&C netmasks which 239 * are probably the most common case... 240 */ 241 if (t->rn_mask) 242 vlen = *(u_char *)t->rn_mask; 243 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 244 for (; cp < cplim; cp++, cp2++) 245 if (*cp != *cp2) 246 goto on1; 247 /* 248 * This extra grot is in case we are explicitly asked 249 * to look up the default. Ugh! 250 */ 251 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 252 t = t->rn_dupedkey; 253 return t; 254 on1: 255 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 256 for (b = 7; (test >>= 1) > 0;) 257 b--; 258 matched_off = cp - v; 259 b += matched_off << 3; 260 rn_b = -1 - b; 261 /* 262 * If there is a host route in a duped-key chain, it will be first. 263 */ 264 if ((saved_t = t)->rn_mask == 0) 265 t = t->rn_dupedkey; 266 for (; t; t = t->rn_dupedkey) 267 /* 268 * Even if we don't match exactly as a host, 269 * we may match if the leaf we wound up at is 270 * a route to a net. 271 */ 272 if (t->rn_flags & RNF_NORMAL) { 273 if (rn_b <= t->rn_b) 274 return t; 275 } else if (rn_satisfies_leaf(v, t, matched_off)) 276 return t; 277 t = saved_t; 278 /* start searching up the tree */ 279 do { 280 struct radix_mask *m; 281 t = t->rn_p; 282 m = t->rn_mklist; 283 if (m) { 284 /* 285 * If non-contiguous masks ever become important 286 * we can restore the masking and open coding of 287 * the search and satisfaction test and put the 288 * calculation of "off" back before the "do". 289 */ 290 do { 291 if (m->rm_flags & RNF_NORMAL) { 292 if (rn_b <= m->rm_b) 293 return (m->rm_leaf); 294 } else { 295 off = min(t->rn_off, matched_off); 296 x = rn_search_m(v, t, m->rm_mask); 297 while (x && x->rn_mask != m->rm_mask) 298 x = x->rn_dupedkey; 299 if (x && rn_satisfies_leaf(v, x, off)) 300 return x; 301 } 302 m = m->rm_mklist; 303 } while (m); 304 } 305 } while (t != top); 306 return 0; 307 } 308 309 #ifdef RN_DEBUG 310 int rn_nodenum; 311 struct radix_node *rn_clist; 312 int rn_saveinfo; 313 int rn_debug = 1; 314 #endif 315 316 struct radix_node * 317 rn_newpair(void *v, int b, struct radix_node nodes[2]) 318 { 319 struct radix_node *tt = nodes, *t = tt + 1; 320 t->rn_b = b; 321 t->rn_bmask = 0x80 >> (b & 7); 322 t->rn_l = tt; 323 t->rn_off = b >> 3; 324 tt->rn_b = -1; 325 tt->rn_key = (caddr_t)v; 326 tt->rn_p = t; 327 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 328 #ifdef RN_DEBUG 329 tt->rn_info = rn_nodenum++; 330 t->rn_info = rn_nodenum++; 331 tt->rn_twin = t; 332 tt->rn_ybro = rn_clist; 333 rn_clist = tt; 334 #endif 335 return t; 336 } 337 338 struct radix_node * 339 rn_insert(void *v_arg, struct radix_node_head *head, 340 int *dupentry, struct radix_node nodes[2]) 341 { 342 caddr_t v = v_arg; 343 struct radix_node *top = head->rnh_treetop; 344 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 345 struct radix_node *t = rn_search(v_arg, top); 346 caddr_t cp = v + head_off; 347 int b; 348 struct radix_node *tt; 349 /* 350 * Find first bit at which v and t->rn_key differ 351 */ 352 { 353 caddr_t cp2 = t->rn_key + head_off; 354 int cmp_res; 355 caddr_t cplim = v + vlen; 356 357 while (cp < cplim) 358 if (*cp2++ != *cp++) 359 goto on1; 360 *dupentry = 1; 361 return t; 362 on1: 363 *dupentry = 0; 364 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 365 for (b = (cp - v) << 3; cmp_res; b--) 366 cmp_res >>= 1; 367 } 368 { 369 struct radix_node *p, *x = top; 370 cp = v; 371 do { 372 p = x; 373 if (cp[x->rn_off] & x->rn_bmask) 374 x = x->rn_r; 375 else 376 x = x->rn_l; 377 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 378 #ifdef RN_DEBUG 379 if (rn_debug) 380 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 381 #endif 382 t = rn_newpair(v_arg, b, nodes); 383 tt = t->rn_l; 384 if ((cp[p->rn_off] & p->rn_bmask) == 0) 385 p->rn_l = t; 386 else 387 p->rn_r = t; 388 x->rn_p = t; 389 t->rn_p = p; /* frees x, p as temp vars below */ 390 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 391 t->rn_r = x; 392 } else { 393 t->rn_r = tt; 394 t->rn_l = x; 395 } 396 #ifdef RN_DEBUG 397 if (rn_debug) 398 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 399 #endif 400 } 401 return (tt); 402 } 403 404 struct radix_node * 405 rn_addmask(void *n_arg, int search, int skip) 406 { 407 caddr_t netmask = (caddr_t)n_arg; 408 struct radix_node *x; 409 caddr_t cp, cplim; 410 int b = 0, mlen, j; 411 int maskduplicated, m0, isnormal; 412 struct radix_node *saved_x; 413 static int last_zeroed = 0; 414 415 if ((mlen = *(u_char *)netmask) > max_keylen) 416 mlen = max_keylen; 417 if (skip == 0) 418 skip = 1; 419 if (mlen <= skip) 420 return (mask_rnhead->rnh_nodes); 421 if (skip > 1) 422 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 423 if ((m0 = mlen) > skip) 424 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 425 /* 426 * Trim trailing zeroes. 427 */ 428 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 429 cp--; 430 mlen = cp - addmask_key; 431 if (mlen <= skip) { 432 if (m0 >= last_zeroed) 433 last_zeroed = mlen; 434 return (mask_rnhead->rnh_nodes); 435 } 436 if (m0 < last_zeroed) 437 Bzero(addmask_key + m0, last_zeroed - m0); 438 *addmask_key = last_zeroed = mlen; 439 x = rn_search(addmask_key, rn_masktop); 440 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 441 x = 0; 442 if (x || search) 443 return (x); 444 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 445 if ((saved_x = x) == 0) 446 return (0); 447 Bzero(x, max_keylen + 2 * sizeof (*x)); 448 netmask = cp = (caddr_t)(x + 2); 449 Bcopy(addmask_key, cp, mlen); 450 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 451 if (maskduplicated) { 452 log(LOG_ERR, "rn_addmask: mask impossibly already in tree\n"); 453 Free(saved_x); 454 return (x); 455 } 456 /* 457 * Calculate index of mask, and check for normalcy. 458 */ 459 cplim = netmask + mlen; 460 isnormal = 1; 461 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 462 cp++; 463 if (cp != cplim) { 464 for (j = 0x80; (j & *cp) != 0; j >>= 1) 465 b++; 466 if (*cp != normal_chars[b] || cp != (cplim - 1)) 467 isnormal = 0; 468 } 469 b += (cp - netmask) << 3; 470 x->rn_b = -1 - b; 471 if (isnormal) 472 x->rn_flags |= RNF_NORMAL; 473 return (x); 474 } 475 476 static int /* XXX: arbitrary ordering for non-contiguous masks */ 477 rn_lexobetter(void *m_arg, void *n_arg) 478 { 479 u_char *mp = m_arg, *np = n_arg, *lim; 480 481 /* 482 * Longer masks might not really be lexicographically better, 483 * but longer masks always have precedence since they must be checked 484 * first. The netmasks were normalized before calling this function and 485 * don't have unneeded trailing zeros. 486 */ 487 if (*mp > *np) 488 return 1; 489 if (*mp < *np) 490 return 0; 491 /* 492 * Must return the first difference between the masks 493 * to ensure deterministic sorting. 494 */ 495 lim = mp + *mp; 496 return (memcmp(mp, np, *lim) > 0); 497 } 498 499 static struct radix_mask * 500 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *next) 501 { 502 struct radix_mask *m; 503 504 MKGet(m); 505 if (m == 0) { 506 log(LOG_ERR, "Mask for route not entered\n"); 507 return (0); 508 } 509 Bzero(m, sizeof *m); 510 m->rm_b = tt->rn_b; 511 m->rm_flags = tt->rn_flags; 512 if (tt->rn_flags & RNF_NORMAL) 513 m->rm_leaf = tt; 514 else 515 m->rm_mask = tt->rn_mask; 516 m->rm_mklist = next; 517 tt->rn_mklist = m; 518 return m; 519 } 520 521 struct radix_node * 522 rn_addroute(void *v_arg, void *n_arg, struct radix_node_head *head, 523 struct radix_node treenodes[2], u_int8_t prio) 524 { 525 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 526 struct radix_node *t, *x = NULL, *tt; 527 struct radix_node *saved_tt, *top = head->rnh_treetop; 528 short b = 0, b_leaf = 0; 529 int keyduplicated, prioinv = -1; 530 caddr_t mmask; 531 struct radix_mask *m, **mp; 532 533 /* 534 * In dealing with non-contiguous masks, there may be 535 * many different routes which have the same mask. 536 * We will find it useful to have a unique pointer to 537 * the mask to speed avoiding duplicate references at 538 * nodes and possibly save time in calculating indices. 539 */ 540 if (netmask) { 541 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 542 return (0); 543 b_leaf = x->rn_b; 544 b = -1 - x->rn_b; 545 netmask = x->rn_key; 546 } 547 /* 548 * Deal with duplicated keys: attach node to previous instance 549 */ 550 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 551 if (keyduplicated) { 552 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 553 #ifndef SMALL_KERNEL 554 /* permit multipath, if enabled for the family */ 555 if (rn_mpath_capable(head) && netmask == tt->rn_mask) { 556 int mid; 557 /* 558 * Try to insert the new node in the middle 559 * of the list of any preexisting multipaths, 560 * to reduce the number of path disruptions 561 * that occur as a result of an insertion, 562 * per RFC2992. 563 * Additionally keep the list sorted by route 564 * priority. 565 */ 566 prioinv = 0; 567 tt = rn_mpath_prio(tt, prio); 568 if (((struct rtentry *)tt)->rt_priority != 569 prio) { 570 /* 571 * rn_mpath_prio returns the previous 572 * element if no element with the 573 * requested priority exists. It could 574 * be that the previous element comes 575 * with a bigger priority. 576 */ 577 if (((struct rtentry *)tt)-> 578 rt_priority > prio) 579 prioinv = 1; 580 t = tt; 581 break; 582 } 583 584 mid = rn_mpath_count(tt) / 2; 585 do { 586 t = tt; 587 tt = rn_mpath_next(tt, 0); 588 } while (tt && --mid > 0); 589 break; 590 } 591 #endif 592 if (tt->rn_mask == netmask) 593 return (0); 594 if (netmask == 0 || 595 (tt->rn_mask && 596 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 597 rn_refines(netmask, tt->rn_mask) || 598 rn_lexobetter(netmask, tt->rn_mask)))) 599 break; 600 } 601 /* 602 * If the mask is not duplicated, we wouldn't 603 * find it among possible duplicate key entries 604 * anyway, so the above test doesn't hurt. 605 * 606 * We sort the masks for a duplicated key the same way as 607 * in a masklist -- most specific to least specific. 608 * This may require the unfortunate nuisance of relocating 609 * the head of the list. 610 * 611 * We also reverse, or doubly link the list through the 612 * parent pointer. 613 */ 614 if (tt == saved_tt && prioinv) { 615 struct radix_node *xx; 616 /* link in at head of list */ 617 (tt = treenodes)->rn_dupedkey = t; 618 tt->rn_flags = t->rn_flags; 619 tt->rn_p = xx = t->rn_p; 620 t->rn_p = tt; 621 if (xx->rn_l == t) 622 xx->rn_l = tt; 623 else 624 xx->rn_r = tt; 625 saved_tt = tt; 626 } else if (prioinv == 1) { 627 (tt = treenodes)->rn_dupedkey = t; 628 if (t->rn_p == NULL) 629 panic("rn_addroute: t->rn_p is NULL"); 630 t->rn_p->rn_dupedkey = tt; 631 tt->rn_p = t->rn_p; 632 t->rn_p = tt; 633 } else { 634 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 635 t->rn_dupedkey = tt; 636 tt->rn_p = t; 637 if (tt->rn_dupedkey) 638 tt->rn_dupedkey->rn_p = tt; 639 } 640 #ifdef RN_DEBUG 641 t=tt+1; 642 tt->rn_info = rn_nodenum++; 643 t->rn_info = rn_nodenum++; 644 tt->rn_twin = t; 645 tt->rn_ybro = rn_clist; 646 rn_clist = tt; 647 #endif 648 tt->rn_key = (caddr_t) v; 649 tt->rn_b = -1; 650 tt->rn_flags = RNF_ACTIVE; 651 } 652 /* 653 * Put mask in tree. 654 */ 655 if (netmask) { 656 tt->rn_mask = netmask; 657 tt->rn_b = x->rn_b; 658 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 659 } 660 t = saved_tt->rn_p; 661 if (keyduplicated) 662 goto on2; 663 b_leaf = -1 - t->rn_b; 664 if (t->rn_r == saved_tt) 665 x = t->rn_l; 666 else 667 x = t->rn_r; 668 /* Promote general routes from below */ 669 if (x->rn_b < 0) { 670 struct radix_node *xx = NULL; 671 for (mp = &t->rn_mklist; x; xx = x, x = x->rn_dupedkey) { 672 if (xx && xx->rn_mklist && xx->rn_mask == x->rn_mask && 673 x->rn_mklist == 0) { 674 /* multipath route, bump refcount on first mklist */ 675 x->rn_mklist = xx->rn_mklist; 676 x->rn_mklist->rm_refs++; 677 } 678 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 679 *mp = m = rn_new_radix_mask(x, 0); 680 if (m) 681 mp = &m->rm_mklist; 682 } 683 } 684 } else if (x->rn_mklist) { 685 /* 686 * Skip over masks whose index is > that of new node 687 */ 688 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 689 if (m->rm_b >= b_leaf) 690 break; 691 t->rn_mklist = m; 692 *mp = 0; 693 } 694 on2: 695 /* Add new route to highest possible ancestor's list */ 696 if ((netmask == 0) || (b > t->rn_b )) 697 return tt; /* can't lift at all */ 698 b_leaf = tt->rn_b; 699 do { 700 x = t; 701 t = t->rn_p; 702 } while (b <= t->rn_b && x != top); 703 /* 704 * Search through routes associated with node to 705 * insert new route according to index. 706 * Need same criteria as when sorting dupedkeys to avoid 707 * double loop on deletion. 708 */ 709 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 710 if (m->rm_b < b_leaf) 711 continue; 712 if (m->rm_b > b_leaf) 713 break; 714 if (m->rm_flags & RNF_NORMAL) { 715 mmask = m->rm_leaf->rn_mask; 716 if (keyduplicated) { 717 if (m->rm_leaf->rn_p == tt) 718 /* new route is better */ 719 m->rm_leaf = tt; 720 #ifdef DIAGNOSTIC 721 else { 722 for (t = m->rm_leaf; t; 723 t = t->rn_dupedkey) 724 if (t == tt) 725 break; 726 if (t == NULL) { 727 log(LOG_ERR, "Non-unique " 728 "normal route on dupedkey, " 729 "mask not entered\n"); 730 return tt; 731 } 732 } 733 #endif 734 m->rm_refs++; 735 tt->rn_mklist = m; 736 return tt; 737 } else if (tt->rn_flags & RNF_NORMAL) { 738 log(LOG_ERR, "Non-unique normal route," 739 " mask not entered\n"); 740 return tt; 741 } 742 } else 743 mmask = m->rm_mask; 744 if (mmask == netmask) { 745 m->rm_refs++; 746 tt->rn_mklist = m; 747 return tt; 748 } 749 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 750 break; 751 } 752 *mp = rn_new_radix_mask(tt, *mp); 753 return tt; 754 } 755 756 struct radix_node * 757 rn_delete(void *v_arg, void *netmask_arg, struct radix_node_head *head, 758 struct radix_node *rn) 759 { 760 struct radix_node *t, *p, *x, *tt; 761 struct radix_mask *m, *saved_m, **mp; 762 struct radix_node *dupedkey, *saved_tt, *top; 763 caddr_t v, netmask; 764 int b, head_off, vlen; 765 766 v = v_arg; 767 netmask = netmask_arg; 768 x = head->rnh_treetop; 769 tt = rn_search(v, x); 770 head_off = x->rn_off; 771 vlen = *(u_char *)v; 772 saved_tt = tt; 773 top = x; 774 if (tt == 0 || 775 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 776 return (0); 777 /* 778 * Delete our route from mask lists. 779 */ 780 if (netmask) { 781 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 782 return (0); 783 netmask = x->rn_key; 784 while (tt->rn_mask != netmask) 785 if ((tt = tt->rn_dupedkey) == 0) 786 return (0); 787 } 788 #ifndef SMALL_KERNEL 789 if (rn) { 790 while (tt != rn) 791 if ((tt = tt->rn_dupedkey) == 0) 792 return (0); 793 } 794 #endif 795 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 796 goto on1; 797 if (tt->rn_flags & RNF_NORMAL) { 798 if (m->rm_leaf != tt && m->rm_refs == 0) { 799 log(LOG_ERR, "rn_delete: inconsistent normal " 800 "annotation\n"); 801 return (0); 802 } 803 if (m->rm_leaf != tt) { 804 if (--m->rm_refs >= 0) 805 goto on1; 806 } 807 /* tt is currently the head of the possible multipath chain */ 808 if (m->rm_refs > 0) { 809 if (tt->rn_dupedkey == NULL || 810 tt->rn_dupedkey->rn_mklist != m) { 811 log(LOG_ERR, "rn_delete: inconsistent " 812 "dupedkey list\n"); 813 return (0); 814 } 815 m->rm_leaf = tt->rn_dupedkey; 816 --m->rm_refs; 817 goto on1; 818 } 819 /* else tt is last and only route */ 820 } else { 821 if (m->rm_mask != tt->rn_mask) { 822 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 823 goto on1; 824 } 825 if (--m->rm_refs >= 0) 826 goto on1; 827 } 828 b = -1 - tt->rn_b; 829 t = saved_tt->rn_p; 830 if (b > t->rn_b) 831 goto on1; /* Wasn't lifted at all */ 832 do { 833 x = t; 834 t = t->rn_p; 835 } while (b <= t->rn_b && x != top); 836 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 837 if (m == saved_m) { 838 *mp = m->rm_mklist; 839 MKFree(m); 840 break; 841 } 842 if (m == 0) { 843 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 844 if (tt->rn_flags & RNF_NORMAL) 845 return (0); /* Dangling ref to us */ 846 } 847 on1: 848 /* 849 * Eliminate us from tree 850 */ 851 if (tt->rn_flags & RNF_ROOT) 852 return (0); 853 #ifdef RN_DEBUG 854 /* Get us out of the creation list */ 855 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) 856 ; 857 if (t) t->rn_ybro = tt->rn_ybro; 858 #endif 859 t = tt->rn_p; 860 dupedkey = saved_tt->rn_dupedkey; 861 if (dupedkey) { 862 /* 863 * Here, tt is the deletion target, and 864 * saved_tt is the head of the dupedkey chain. 865 */ 866 if (tt == saved_tt) { 867 x = dupedkey; 868 x->rn_p = t; 869 if (t->rn_l == tt) 870 t->rn_l = x; 871 else 872 t->rn_r = x; 873 } else { 874 x = saved_tt; 875 t->rn_dupedkey = tt->rn_dupedkey; 876 if (tt->rn_dupedkey) 877 tt->rn_dupedkey->rn_p = t; 878 } 879 t = tt + 1; 880 if (t->rn_flags & RNF_ACTIVE) { 881 #ifndef RN_DEBUG 882 *++x = *t; 883 p = t->rn_p; 884 #else 885 b = t->rn_info; 886 *++x = *t; 887 t->rn_info = b; 888 p = t->rn_p; 889 #endif 890 if (p->rn_l == t) 891 p->rn_l = x; 892 else 893 p->rn_r = x; 894 x->rn_l->rn_p = x; 895 x->rn_r->rn_p = x; 896 } 897 goto out; 898 } 899 if (t->rn_l == tt) 900 x = t->rn_r; 901 else 902 x = t->rn_l; 903 p = t->rn_p; 904 if (p->rn_r == t) 905 p->rn_r = x; 906 else 907 p->rn_l = x; 908 x->rn_p = p; 909 /* 910 * Demote routes attached to us. 911 */ 912 if (t->rn_mklist) { 913 if (x->rn_b >= 0) { 914 for (mp = &x->rn_mklist; (m = *mp);) 915 mp = &m->rm_mklist; 916 *mp = t->rn_mklist; 917 } else { 918 /* If there are any key,mask pairs in a sibling 919 duped-key chain, some subset will appear sorted 920 in the same order attached to our mklist */ 921 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 922 if (m == x->rn_mklist) { 923 struct radix_mask *mm = m->rm_mklist; 924 x->rn_mklist = 0; 925 if (--(m->rm_refs) < 0) 926 MKFree(m); 927 else if (m->rm_flags & RNF_NORMAL) 928 /* 929 * don't progress because this 930 * a multipath route. Next 931 * route will use the same m. 932 */ 933 mm = m; 934 m = mm; 935 } 936 if (m) 937 log(LOG_ERR, "%s %p at %p\n", 938 "rn_delete: Orphaned Mask", m, x); 939 } 940 } 941 /* 942 * We may be holding an active internal node in the tree. 943 */ 944 x = tt + 1; 945 if (t != x) { 946 #ifndef RN_DEBUG 947 *t = *x; 948 #else 949 b = t->rn_info; 950 *t = *x; 951 t->rn_info = b; 952 #endif 953 t->rn_l->rn_p = t; 954 t->rn_r->rn_p = t; 955 p = x->rn_p; 956 if (p->rn_l == x) 957 p->rn_l = t; 958 else 959 p->rn_r = t; 960 } 961 out: 962 tt->rn_flags &= ~RNF_ACTIVE; 963 tt[1].rn_flags &= ~RNF_ACTIVE; 964 return (tt); 965 } 966 967 int 968 rn_walktree(struct radix_node_head *h, int (*f)(struct radix_node *, void *, 969 u_int), void *w) 970 { 971 int error; 972 struct radix_node *base, *next; 973 struct radix_node *rn = h->rnh_treetop; 974 /* 975 * This gets complicated because we may delete the node 976 * while applying the function f to it, so we need to calculate 977 * the successor node in advance. 978 */ 979 /* First time through node, go left */ 980 while (rn->rn_b >= 0) 981 rn = rn->rn_l; 982 for (;;) { 983 base = rn; 984 /* If at right child go back up, otherwise, go right */ 985 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 986 rn = rn->rn_p; 987 /* Find the next *leaf* since next node might vanish, too */ 988 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 989 rn = rn->rn_l; 990 next = rn; 991 /* Process leaves */ 992 while ((rn = base) != NULL) { 993 base = rn->rn_dupedkey; 994 if (!(rn->rn_flags & RNF_ROOT) && 995 (error = (*f)(rn, w, h->rnh_rtableid))) 996 return (error); 997 } 998 rn = next; 999 if (rn->rn_flags & RNF_ROOT) 1000 return (0); 1001 } 1002 /* NOTREACHED */ 1003 } 1004 1005 int 1006 rn_inithead(void **head, int off) 1007 { 1008 struct radix_node_head *rnh; 1009 1010 if (*head) 1011 return (1); 1012 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 1013 if (rnh == 0) 1014 return (0); 1015 *head = rnh; 1016 return rn_inithead0(rnh, off); 1017 } 1018 1019 int 1020 rn_inithead0(struct radix_node_head *rnh, int off) 1021 { 1022 struct radix_node *t, *tt, *ttt; 1023 1024 Bzero(rnh, sizeof (*rnh)); 1025 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1026 ttt = rnh->rnh_nodes + 2; 1027 t->rn_r = ttt; 1028 t->rn_p = t; 1029 tt = t->rn_l; 1030 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 1031 tt->rn_b = -1 - off; 1032 *ttt = *tt; 1033 ttt->rn_key = rn_ones; 1034 rnh->rnh_addaddr = rn_addroute; 1035 rnh->rnh_deladdr = rn_delete; 1036 rnh->rnh_matchaddr = rn_match; 1037 rnh->rnh_lookup = rn_lookup; 1038 rnh->rnh_walktree = rn_walktree; 1039 rnh->rnh_treetop = t; 1040 return (1); 1041 } 1042 1043 void 1044 rn_init() 1045 { 1046 char *cp, *cplim; 1047 #ifdef _KERNEL 1048 struct domain *dom; 1049 1050 for (dom = domains; dom; dom = dom->dom_next) 1051 if (dom->dom_maxrtkey > max_keylen) 1052 max_keylen = dom->dom_maxrtkey; 1053 #endif 1054 if (max_keylen == 0) { 1055 log(LOG_ERR, 1056 "rn_init: radix functions require max_keylen be set\n"); 1057 return; 1058 } 1059 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1060 if (rn_zeros == NULL) 1061 panic("rn_init"); 1062 Bzero(rn_zeros, 3 * max_keylen); 1063 rn_ones = cp = rn_zeros + max_keylen; 1064 addmask_key = cplim = rn_ones + max_keylen; 1065 while (cp < cplim) 1066 *cp++ = -1; 1067 if (rn_inithead((void *)&mask_rnhead, 0) == 0) 1068 panic("rn_init 2"); 1069 } 1070