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 8.5 (Berkeley) 5/19/95 34 * $FreeBSD$ 35 */ 36 37 /* 38 * Routines to build and maintain radix trees for routing lookups. 39 */ 40 #ifndef _RADIX_H_ 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 #endif 52 53 static int rn_walktree_from(struct radix_node_head *h, void *a, void *m, 54 walktree_f_t *f, void *w); 55 static int rn_walktree(struct radix_node_head *, walktree_f_t *, void *); 56 static struct radix_node 57 *rn_insert(void *, struct radix_node_head *, int *, 58 struct radix_node [2]), 59 *rn_newpair(void *, int, struct radix_node[2]), 60 *rn_search(void *, struct radix_node *), 61 *rn_search_m(void *, struct radix_node *, void *); 62 63 static int max_keylen; 64 static struct radix_mask *rn_mkfreelist; 65 static struct radix_node_head *mask_rnhead; 66 static char *addmask_key; 67 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 68 static char *rn_zeros, *rn_ones; 69 70 #define rn_masktop (mask_rnhead->rnh_treetop) 71 #undef Bcmp 72 #define Bcmp(a, b, l) \ 73 ((l) == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)(l))) 74 75 static int rn_lexobetter(void *m_arg, void *n_arg); 76 static struct radix_mask * 77 rn_new_radix_mask(struct radix_node *tt, 78 struct radix_mask *next); 79 static int rn_satisfies_leaf(char *trial, struct radix_node *leaf, 80 int skip); 81 82 /* 83 * The data structure for the keys is a radix tree with one way 84 * branching removed. The index rn_bit at an internal node n represents a bit 85 * position to be tested. The tree is arranged so that all descendants 86 * of a node n have keys whose bits all agree up to position rn_bit - 1. 87 * (We say the index of n is rn_bit.) 88 * 89 * There is at least one descendant which has a one bit at position rn_bit, 90 * and at least one with a zero there. 91 * 92 * A route is determined by a pair of key and mask. We require that the 93 * bit-wise logical and of the key and mask to be the key. 94 * We define the index of a route to associated with the mask to be 95 * the first bit number in the mask where 0 occurs (with bit number 0 96 * representing the highest order bit). 97 * 98 * We say a mask is normal if every bit is 0, past the index of the mask. 99 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit, 100 * and m is a normal mask, then the route applies to every descendant of n. 101 * If the index(m) < rn_bit, this implies the trailing last few bits of k 102 * before bit b are all 0, (and hence consequently true of every descendant 103 * of n), so the route applies to all descendants of the node as well. 104 * 105 * Similar logic shows that a non-normal mask m such that 106 * index(m) <= index(n) could potentially apply to many children of n. 107 * Thus, for each non-host route, we attach its mask to a list at an internal 108 * node as high in the tree as we can go. 109 * 110 * The present version of the code makes use of normal routes in short- 111 * circuiting an explict mask and compare operation when testing whether 112 * a key satisfies a normal route, and also in remembering the unique leaf 113 * that governs a subtree. 114 */ 115 116 static struct radix_node * 117 rn_search(v_arg, head) 118 void *v_arg; 119 struct radix_node *head; 120 { 121 register struct radix_node *x; 122 register caddr_t v; 123 124 for (x = head, v = v_arg; x->rn_bit >= 0;) { 125 if (x->rn_bmask & v[x->rn_offset]) 126 x = x->rn_right; 127 else 128 x = x->rn_left; 129 } 130 return (x); 131 } 132 133 static struct radix_node * 134 rn_search_m(v_arg, head, m_arg) 135 struct radix_node *head; 136 void *v_arg, *m_arg; 137 { 138 register struct radix_node *x; 139 register caddr_t v = v_arg, m = m_arg; 140 141 for (x = head; x->rn_bit >= 0;) { 142 if ((x->rn_bmask & m[x->rn_offset]) && 143 (x->rn_bmask & v[x->rn_offset])) 144 x = x->rn_right; 145 else 146 x = x->rn_left; 147 } 148 return x; 149 } 150 151 int 152 rn_refines(m_arg, n_arg) 153 void *m_arg, *n_arg; 154 { 155 register caddr_t m = m_arg, n = n_arg; 156 register caddr_t lim, lim2 = lim = n + *(u_char *)n; 157 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 158 int masks_are_equal = 1; 159 160 if (longer > 0) 161 lim -= longer; 162 while (n < lim) { 163 if (*n & ~(*m)) 164 return 0; 165 if (*n++ != *m++) 166 masks_are_equal = 0; 167 } 168 while (n < lim2) 169 if (*n++) 170 return 0; 171 if (masks_are_equal && (longer < 0)) 172 for (lim2 = m - longer; m < lim2; ) 173 if (*m++) 174 return 1; 175 return (!masks_are_equal); 176 } 177 178 struct radix_node * 179 rn_lookup(v_arg, m_arg, head) 180 void *v_arg, *m_arg; 181 struct radix_node_head *head; 182 { 183 register struct radix_node *x; 184 caddr_t netmask = 0; 185 186 if (m_arg) { 187 x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_offset); 188 if (x == 0) 189 return (0); 190 netmask = x->rn_key; 191 } 192 x = rn_match(v_arg, head); 193 if (x && netmask) { 194 while (x && x->rn_mask != netmask) 195 x = x->rn_dupedkey; 196 } 197 return x; 198 } 199 200 static int 201 rn_satisfies_leaf(trial, leaf, skip) 202 char *trial; 203 register struct radix_node *leaf; 204 int skip; 205 { 206 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 207 char *cplim; 208 int length = min(*(u_char *)cp, *(u_char *)cp2); 209 210 if (cp3 == 0) 211 cp3 = rn_ones; 212 else 213 length = min(length, *(u_char *)cp3); 214 cplim = cp + length; cp3 += skip; cp2 += skip; 215 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 216 if ((*cp ^ *cp2) & *cp3) 217 return 0; 218 return 1; 219 } 220 221 struct radix_node * 222 rn_match(v_arg, head) 223 void *v_arg; 224 struct radix_node_head *head; 225 { 226 caddr_t v = v_arg; 227 register struct radix_node *t = head->rnh_treetop, *x; 228 register caddr_t cp = v, cp2; 229 caddr_t cplim; 230 struct radix_node *saved_t, *top = t; 231 int off = t->rn_offset, vlen = *(u_char *)cp, matched_off; 232 register int test, b, rn_bit; 233 234 /* 235 * Open code rn_search(v, top) to avoid overhead of extra 236 * subroutine call. 237 */ 238 for (; t->rn_bit >= 0; ) { 239 if (t->rn_bmask & cp[t->rn_offset]) 240 t = t->rn_right; 241 else 242 t = t->rn_left; 243 } 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) 256 vlen = *(u_char *)t->rn_mask; 257 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 258 for (; cp < cplim; cp++, cp2++) 259 if (*cp != *cp2) 260 goto on1; 261 /* 262 * This extra grot is in case we are explicitly asked 263 * to look up the default. Ugh! 264 * 265 * Never return the root node itself, it seems to cause a 266 * lot of confusion. 267 */ 268 if (t->rn_flags & RNF_ROOT) 269 t = t->rn_dupedkey; 270 return t; 271 on1: 272 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 273 for (b = 7; (test >>= 1) > 0;) 274 b--; 275 matched_off = cp - v; 276 b += matched_off << 3; 277 rn_bit = -1 - b; 278 /* 279 * If there is a host route in a duped-key chain, it will be first. 280 */ 281 if ((saved_t = t)->rn_mask == 0) 282 t = t->rn_dupedkey; 283 for (; t; t = t->rn_dupedkey) 284 /* 285 * Even if we don't match exactly as a host, 286 * we may match if the leaf we wound up at is 287 * a route to a net. 288 */ 289 if (t->rn_flags & RNF_NORMAL) { 290 if (rn_bit <= t->rn_bit) 291 return t; 292 } else if (rn_satisfies_leaf(v, t, matched_off)) 293 return t; 294 t = saved_t; 295 /* start searching up the tree */ 296 do { 297 register struct radix_mask *m; 298 t = t->rn_parent; 299 m = t->rn_mklist; 300 /* 301 * If non-contiguous masks ever become important 302 * we can restore the masking and open coding of 303 * the search and satisfaction test and put the 304 * calculation of "off" back before the "do". 305 */ 306 while (m) { 307 if (m->rm_flags & RNF_NORMAL) { 308 if (rn_bit <= m->rm_bit) 309 return (m->rm_leaf); 310 } else { 311 off = min(t->rn_offset, matched_off); 312 x = rn_search_m(v, t, m->rm_mask); 313 while (x && x->rn_mask != m->rm_mask) 314 x = x->rn_dupedkey; 315 if (x && rn_satisfies_leaf(v, x, off)) 316 return x; 317 } 318 m = m->rm_mklist; 319 } 320 } while (t != top); 321 return 0; 322 } 323 324 #ifdef RN_DEBUG 325 int rn_nodenum; 326 struct radix_node *rn_clist; 327 int rn_saveinfo; 328 int rn_debug = 1; 329 #endif 330 331 static struct radix_node * 332 rn_newpair(v, b, nodes) 333 void *v; 334 int b; 335 struct radix_node nodes[2]; 336 { 337 register struct radix_node *tt = nodes, *t = tt + 1; 338 t->rn_bit = b; 339 t->rn_bmask = 0x80 >> (b & 7); 340 t->rn_left = tt; 341 t->rn_offset = b >> 3; 342 tt->rn_bit = -1; 343 tt->rn_key = (caddr_t)v; 344 tt->rn_parent = t; 345 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 346 tt->rn_mklist = t->rn_mklist = 0; 347 #ifdef RN_DEBUG 348 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 349 tt->rn_twin = t; 350 tt->rn_ybro = rn_clist; 351 rn_clist = tt; 352 #endif 353 return t; 354 } 355 356 static struct radix_node * 357 rn_insert(v_arg, head, dupentry, nodes) 358 void *v_arg; 359 struct radix_node_head *head; 360 int *dupentry; 361 struct radix_node nodes[2]; 362 { 363 caddr_t v = v_arg; 364 struct radix_node *top = head->rnh_treetop; 365 int head_off = top->rn_offset, vlen = (int)*((u_char *)v); 366 register struct radix_node *t = rn_search(v_arg, top); 367 register caddr_t cp = v + head_off; 368 register int b; 369 struct radix_node *tt; 370 /* 371 * Find first bit at which v and t->rn_key differ 372 */ 373 { 374 register caddr_t cp2 = t->rn_key + head_off; 375 register int cmp_res; 376 caddr_t cplim = v + vlen; 377 378 while (cp < cplim) 379 if (*cp2++ != *cp++) 380 goto on1; 381 *dupentry = 1; 382 return t; 383 on1: 384 *dupentry = 0; 385 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 386 for (b = (cp - v) << 3; cmp_res; b--) 387 cmp_res >>= 1; 388 } 389 { 390 register struct radix_node *p, *x = top; 391 cp = v; 392 do { 393 p = x; 394 if (cp[x->rn_offset] & x->rn_bmask) 395 x = x->rn_right; 396 else 397 x = x->rn_left; 398 } while (b > (unsigned) x->rn_bit); 399 /* x->rn_bit < b && x->rn_bit >= 0 */ 400 #ifdef RN_DEBUG 401 if (rn_debug) 402 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 403 #endif 404 t = rn_newpair(v_arg, b, nodes); 405 tt = t->rn_left; 406 if ((cp[p->rn_offset] & p->rn_bmask) == 0) 407 p->rn_left = t; 408 else 409 p->rn_right = t; 410 x->rn_parent = t; 411 t->rn_parent = p; /* frees x, p as temp vars below */ 412 if ((cp[t->rn_offset] & t->rn_bmask) == 0) { 413 t->rn_right = x; 414 } else { 415 t->rn_right = tt; 416 t->rn_left = x; 417 } 418 #ifdef RN_DEBUG 419 if (rn_debug) 420 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 421 #endif 422 } 423 return (tt); 424 } 425 426 struct radix_node * 427 rn_addmask(n_arg, search, skip) 428 int search, skip; 429 void *n_arg; 430 { 431 caddr_t netmask = (caddr_t)n_arg; 432 register struct radix_node *x; 433 register caddr_t cp, cplim; 434 register int b = 0, mlen, j; 435 int maskduplicated, m0, isnormal; 436 struct radix_node *saved_x; 437 static int last_zeroed = 0; 438 439 if ((mlen = *(u_char *)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, rn_masktop); 464 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 465 x = 0; 466 if (x || search) 467 return (x); 468 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 469 if ((saved_x = x) == 0) 470 return (0); 471 Bzero(x, max_keylen + 2 * sizeof (*x)); 472 netmask = cp = (caddr_t)(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 cplim = netmask + mlen; isnormal = 1; 484 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 485 cp++; 486 if (cp != cplim) { 487 for (j = 0x80; (j & *cp) != 0; j >>= 1) 488 b++; 489 if (*cp != normal_chars[b] || cp != (cplim - 1)) 490 isnormal = 0; 491 } 492 b += (cp - netmask) << 3; 493 x->rn_bit = -1 - b; 494 if (isnormal) 495 x->rn_flags |= RNF_NORMAL; 496 return (x); 497 } 498 499 static int /* XXX: arbitrary ordering for non-contiguous masks */ 500 rn_lexobetter(m_arg, n_arg) 501 void *m_arg, *n_arg; 502 { 503 register u_char *mp = m_arg, *np = n_arg, *lim; 504 505 if (*mp > *np) 506 return 1; /* not really, but need to check longer one first */ 507 if (*mp == *np) 508 for (lim = mp + *mp; mp < lim;) 509 if (*mp++ > *np++) 510 return 1; 511 return 0; 512 } 513 514 static struct radix_mask * 515 rn_new_radix_mask(tt, next) 516 register struct radix_node *tt; 517 register struct radix_mask *next; 518 { 519 register struct radix_mask *m; 520 521 MKGet(m); 522 if (m == 0) { 523 log(LOG_ERR, "Mask for route not entered\n"); 524 return (0); 525 } 526 Bzero(m, sizeof *m); 527 m->rm_bit = tt->rn_bit; 528 m->rm_flags = tt->rn_flags; 529 if (tt->rn_flags & RNF_NORMAL) 530 m->rm_leaf = tt; 531 else 532 m->rm_mask = tt->rn_mask; 533 m->rm_mklist = next; 534 tt->rn_mklist = m; 535 return m; 536 } 537 538 struct radix_node * 539 rn_addroute(v_arg, n_arg, head, treenodes) 540 void *v_arg, *n_arg; 541 struct radix_node_head *head; 542 struct radix_node treenodes[2]; 543 { 544 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 545 register struct radix_node *t, *x = 0, *tt; 546 struct radix_node *saved_tt, *top = head->rnh_treetop; 547 short b = 0, b_leaf = 0; 548 int keyduplicated; 549 caddr_t mmask; 550 struct radix_mask *m, **mp; 551 552 /* 553 * In dealing with non-contiguous masks, there may be 554 * many different routes which have the same mask. 555 * We will find it useful to have a unique pointer to 556 * the mask to speed avoiding duplicate references at 557 * nodes and possibly save time in calculating indices. 558 */ 559 if (netmask) { 560 if ((x = rn_addmask(netmask, 0, top->rn_offset)) == 0) 561 return (0); 562 b_leaf = x->rn_bit; 563 b = -1 - x->rn_bit; 564 netmask = x->rn_key; 565 } 566 /* 567 * Deal with duplicated keys: attach node to previous instance 568 */ 569 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 570 if (keyduplicated) { 571 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 572 if (tt->rn_mask == netmask) 573 return (0); 574 if (netmask == 0 || 575 (tt->rn_mask && 576 ((b_leaf < tt->rn_bit) /* index(netmask) > node */ 577 || rn_refines(netmask, tt->rn_mask) 578 || rn_lexobetter(netmask, tt->rn_mask)))) 579 break; 580 } 581 /* 582 * If the mask is not duplicated, we wouldn't 583 * find it among possible duplicate key entries 584 * anyway, so the above test doesn't hurt. 585 * 586 * We sort the masks for a duplicated key the same way as 587 * in a masklist -- most specific to least specific. 588 * This may require the unfortunate nuisance of relocating 589 * the head of the list. 590 * 591 * We also reverse, or doubly link the list through the 592 * parent pointer. 593 */ 594 if (tt == saved_tt) { 595 struct radix_node *xx = x; 596 /* link in at head of list */ 597 (tt = treenodes)->rn_dupedkey = t; 598 tt->rn_flags = t->rn_flags; 599 tt->rn_parent = x = t->rn_parent; 600 t->rn_parent = tt; /* parent */ 601 if (x->rn_left == t) 602 x->rn_left = tt; 603 else 604 x->rn_right = tt; 605 saved_tt = tt; x = xx; 606 } else { 607 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 608 t->rn_dupedkey = tt; 609 tt->rn_parent = t; /* parent */ 610 if (tt->rn_dupedkey) /* parent */ 611 tt->rn_dupedkey->rn_parent = tt; /* parent */ 612 } 613 #ifdef RN_DEBUG 614 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 615 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 616 #endif 617 tt->rn_key = (caddr_t) v; 618 tt->rn_bit = -1; 619 tt->rn_flags = RNF_ACTIVE; 620 } 621 /* 622 * Put mask in tree. 623 */ 624 if (netmask) { 625 tt->rn_mask = netmask; 626 tt->rn_bit = x->rn_bit; 627 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 628 } 629 t = saved_tt->rn_parent; 630 if (keyduplicated) 631 goto on2; 632 b_leaf = -1 - t->rn_bit; 633 if (t->rn_right == saved_tt) 634 x = t->rn_left; 635 else 636 x = t->rn_right; 637 /* Promote general routes from below */ 638 if (x->rn_bit < 0) { 639 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 640 if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) { 641 *mp = m = rn_new_radix_mask(x, 0); 642 if (m) 643 mp = &m->rm_mklist; 644 } 645 } else if (x->rn_mklist) { 646 /* 647 * Skip over masks whose index is > that of new node 648 */ 649 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 650 if (m->rm_bit >= b_leaf) 651 break; 652 t->rn_mklist = m; *mp = 0; 653 } 654 on2: 655 /* Add new route to highest possible ancestor's list */ 656 if ((netmask == 0) || (b > t->rn_bit )) 657 return tt; /* can't lift at all */ 658 b_leaf = tt->rn_bit; 659 do { 660 x = t; 661 t = t->rn_parent; 662 } while (b <= t->rn_bit && x != top); 663 /* 664 * Search through routes associated with node to 665 * insert new route according to index. 666 * Need same criteria as when sorting dupedkeys to avoid 667 * double loop on deletion. 668 */ 669 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 670 if (m->rm_bit < b_leaf) 671 continue; 672 if (m->rm_bit > b_leaf) 673 break; 674 if (m->rm_flags & RNF_NORMAL) { 675 mmask = m->rm_leaf->rn_mask; 676 if (tt->rn_flags & RNF_NORMAL) { 677 log(LOG_ERR, 678 "Non-unique normal route, mask not entered\n"); 679 return tt; 680 } 681 } else 682 mmask = m->rm_mask; 683 if (mmask == netmask) { 684 m->rm_refs++; 685 tt->rn_mklist = m; 686 return tt; 687 } 688 if (rn_refines(netmask, mmask) 689 || rn_lexobetter(netmask, mmask)) 690 break; 691 } 692 *mp = rn_new_radix_mask(tt, *mp); 693 return tt; 694 } 695 696 struct radix_node * 697 rn_delete(v_arg, netmask_arg, head) 698 void *v_arg, *netmask_arg; 699 struct radix_node_head *head; 700 { 701 register struct radix_node *t, *p, *x, *tt; 702 struct radix_mask *m, *saved_m, **mp; 703 struct radix_node *dupedkey, *saved_tt, *top; 704 caddr_t v, netmask; 705 int b, head_off, vlen; 706 707 v = v_arg; 708 netmask = netmask_arg; 709 x = head->rnh_treetop; 710 tt = rn_search(v, x); 711 head_off = x->rn_offset; 712 vlen = *(u_char *)v; 713 saved_tt = tt; 714 top = x; 715 if (tt == 0 || 716 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 717 return (0); 718 /* 719 * Delete our route from mask lists. 720 */ 721 if (netmask) { 722 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 723 return (0); 724 netmask = x->rn_key; 725 while (tt->rn_mask != netmask) 726 if ((tt = tt->rn_dupedkey) == 0) 727 return (0); 728 } 729 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 730 goto on1; 731 if (tt->rn_flags & RNF_NORMAL) { 732 if (m->rm_leaf != tt || m->rm_refs > 0) { 733 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 734 return 0; /* dangling ref could cause disaster */ 735 } 736 } else { 737 if (m->rm_mask != tt->rn_mask) { 738 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 739 goto on1; 740 } 741 if (--m->rm_refs >= 0) 742 goto on1; 743 } 744 b = -1 - tt->rn_bit; 745 t = saved_tt->rn_parent; 746 if (b > t->rn_bit) 747 goto on1; /* Wasn't lifted at all */ 748 do { 749 x = t; 750 t = t->rn_parent; 751 } while (b <= t->rn_bit && x != top); 752 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 753 if (m == saved_m) { 754 *mp = m->rm_mklist; 755 MKFree(m); 756 break; 757 } 758 if (m == 0) { 759 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 760 if (tt->rn_flags & RNF_NORMAL) 761 return (0); /* Dangling ref to us */ 762 } 763 on1: 764 /* 765 * Eliminate us from tree 766 */ 767 if (tt->rn_flags & RNF_ROOT) 768 return (0); 769 #ifdef RN_DEBUG 770 /* Get us out of the creation list */ 771 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 772 if (t) t->rn_ybro = tt->rn_ybro; 773 #endif 774 t = tt->rn_parent; 775 dupedkey = saved_tt->rn_dupedkey; 776 if (dupedkey) { 777 /* 778 * Here, tt is the deletion target and 779 * saved_tt is the head of the dupekey chain. 780 */ 781 if (tt == saved_tt) { 782 /* remove from head of chain */ 783 x = dupedkey; x->rn_parent = t; 784 if (t->rn_left == tt) 785 t->rn_left = x; 786 else 787 t->rn_right = x; 788 } else { 789 /* find node in front of tt on the chain */ 790 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 791 p = p->rn_dupedkey; 792 if (p) { 793 p->rn_dupedkey = tt->rn_dupedkey; 794 if (tt->rn_dupedkey) /* parent */ 795 tt->rn_dupedkey->rn_parent = p; 796 /* parent */ 797 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 798 } 799 t = tt + 1; 800 if (t->rn_flags & RNF_ACTIVE) { 801 #ifndef RN_DEBUG 802 *++x = *t; 803 p = t->rn_parent; 804 #else 805 b = t->rn_info; 806 *++x = *t; 807 t->rn_info = b; 808 p = t->rn_parent; 809 #endif 810 if (p->rn_left == t) 811 p->rn_left = x; 812 else 813 p->rn_right = x; 814 x->rn_left->rn_parent = x; 815 x->rn_right->rn_parent = x; 816 } 817 goto out; 818 } 819 if (t->rn_left == tt) 820 x = t->rn_right; 821 else 822 x = t->rn_left; 823 p = t->rn_parent; 824 if (p->rn_right == t) 825 p->rn_right = x; 826 else 827 p->rn_left = x; 828 x->rn_parent = p; 829 /* 830 * Demote routes attached to us. 831 */ 832 if (t->rn_mklist) { 833 if (x->rn_bit >= 0) { 834 for (mp = &x->rn_mklist; (m = *mp);) 835 mp = &m->rm_mklist; 836 *mp = t->rn_mklist; 837 } else { 838 /* If there are any key,mask pairs in a sibling 839 duped-key chain, some subset will appear sorted 840 in the same order attached to our mklist */ 841 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 842 if (m == x->rn_mklist) { 843 struct radix_mask *mm = m->rm_mklist; 844 x->rn_mklist = 0; 845 if (--(m->rm_refs) < 0) 846 MKFree(m); 847 m = mm; 848 } 849 if (m) 850 log(LOG_ERR, 851 "rn_delete: Orphaned Mask %p at %p\n", 852 (void *)m, (void *)x); 853 } 854 } 855 /* 856 * We may be holding an active internal node in the tree. 857 */ 858 x = tt + 1; 859 if (t != x) { 860 #ifndef RN_DEBUG 861 *t = *x; 862 #else 863 b = t->rn_info; 864 *t = *x; 865 t->rn_info = b; 866 #endif 867 t->rn_left->rn_parent = t; 868 t->rn_right->rn_parent = t; 869 p = x->rn_parent; 870 if (p->rn_left == x) 871 p->rn_left = t; 872 else 873 p->rn_right = t; 874 } 875 out: 876 tt->rn_flags &= ~RNF_ACTIVE; 877 tt[1].rn_flags &= ~RNF_ACTIVE; 878 return (tt); 879 } 880 881 /* 882 * This is the same as rn_walktree() except for the parameters and the 883 * exit. 884 */ 885 static int 886 rn_walktree_from(h, a, m, f, w) 887 struct radix_node_head *h; 888 void *a, *m; 889 walktree_f_t *f; 890 void *w; 891 { 892 int error; 893 struct radix_node *base, *next; 894 u_char *xa = (u_char *)a; 895 u_char *xm = (u_char *)m; 896 register struct radix_node *rn, *last = 0 /* shut up gcc */; 897 int stopping = 0; 898 int lastb; 899 900 /* 901 * rn_search_m is sort-of-open-coded here. 902 */ 903 /* printf("about to search\n"); */ 904 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) { 905 last = rn; 906 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n", 907 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */ 908 if (!(rn->rn_bmask & xm[rn->rn_offset])) { 909 break; 910 } 911 if (rn->rn_bmask & xa[rn->rn_offset]) { 912 rn = rn->rn_right; 913 } else { 914 rn = rn->rn_left; 915 } 916 } 917 /* printf("done searching\n"); */ 918 919 /* 920 * Two cases: either we stepped off the end of our mask, 921 * in which case last == rn, or we reached a leaf, in which 922 * case we want to start from the last node we looked at. 923 * Either way, last is the node we want to start from. 924 */ 925 rn = last; 926 lastb = rn->rn_bit; 927 928 /* printf("rn %p, lastb %d\n", rn, lastb);*/ 929 930 /* 931 * This gets complicated because we may delete the node 932 * while applying the function f to it, so we need to calculate 933 * the successor node in advance. 934 */ 935 while (rn->rn_bit >= 0) 936 rn = rn->rn_left; 937 938 while (!stopping) { 939 /* printf("node %p (%d)\n", rn, rn->rn_bit); */ 940 base = rn; 941 /* If at right child go back up, otherwise, go right */ 942 while (rn->rn_parent->rn_right == rn 943 && !(rn->rn_flags & RNF_ROOT)) { 944 rn = rn->rn_parent; 945 946 /* if went up beyond last, stop */ 947 if (rn->rn_bit < lastb) { 948 stopping = 1; 949 /* printf("up too far\n"); */ 950 } 951 } 952 953 /* Find the next *leaf* since next node might vanish, too */ 954 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 955 rn = rn->rn_left; 956 next = rn; 957 /* Process leaves */ 958 while ((rn = base) != 0) { 959 base = rn->rn_dupedkey; 960 /* printf("leaf %p\n", rn); */ 961 if (!(rn->rn_flags & RNF_ROOT) 962 && (error = (*f)(rn, w))) 963 return (error); 964 } 965 rn = next; 966 967 if (rn->rn_flags & RNF_ROOT) { 968 /* printf("root, stopping"); */ 969 stopping = 1; 970 } 971 972 } 973 return 0; 974 } 975 976 static int 977 rn_walktree(h, f, w) 978 struct radix_node_head *h; 979 walktree_f_t *f; 980 void *w; 981 { 982 int error; 983 struct radix_node *base, *next; 984 register struct radix_node *rn = h->rnh_treetop; 985 /* 986 * This gets complicated because we may delete the node 987 * while applying the function f to it, so we need to calculate 988 * the successor node in advance. 989 */ 990 /* First time through node, go left */ 991 while (rn->rn_bit >= 0) 992 rn = rn->rn_left; 993 for (;;) { 994 base = rn; 995 /* If at right child go back up, otherwise, go right */ 996 while (rn->rn_parent->rn_right == rn 997 && (rn->rn_flags & RNF_ROOT) == 0) 998 rn = rn->rn_parent; 999 /* Find the next *leaf* since next node might vanish, too */ 1000 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 1001 rn = rn->rn_left; 1002 next = rn; 1003 /* Process leaves */ 1004 while ((rn = base)) { 1005 base = rn->rn_dupedkey; 1006 if (!(rn->rn_flags & RNF_ROOT) 1007 && (error = (*f)(rn, w))) 1008 return (error); 1009 } 1010 rn = next; 1011 if (rn->rn_flags & RNF_ROOT) 1012 return (0); 1013 } 1014 /* NOTREACHED */ 1015 } 1016 1017 int 1018 rn_inithead(head, off) 1019 void **head; 1020 int off; 1021 { 1022 register struct radix_node_head *rnh; 1023 register struct radix_node *t, *tt, *ttt; 1024 if (*head) 1025 return (1); 1026 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 1027 if (rnh == 0) 1028 return (0); 1029 Bzero(rnh, sizeof (*rnh)); 1030 RADIX_NODE_HEAD_LOCK_INIT(rnh); 1031 *head = rnh; 1032 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1033 ttt = rnh->rnh_nodes + 2; 1034 t->rn_right = ttt; 1035 t->rn_parent = t; 1036 tt = t->rn_left; 1037 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 1038 tt->rn_bit = -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_walktree = rn_walktree; 1046 rnh->rnh_walktree_from = rn_walktree_from; 1047 rnh->rnh_treetop = t; 1048 return (1); 1049 } 1050 1051 void 1052 rn_init() 1053 { 1054 char *cp, *cplim; 1055 #ifdef _KERNEL 1056 struct domain *dom; 1057 1058 for (dom = domains; dom; dom = dom->dom_next) 1059 if (dom->dom_maxrtkey > max_keylen) 1060 max_keylen = dom->dom_maxrtkey; 1061 #endif 1062 if (max_keylen == 0) { 1063 log(LOG_ERR, 1064 "rn_init: radix functions require max_keylen be set\n"); 1065 return; 1066 } 1067 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1068 if (rn_zeros == NULL) 1069 panic("rn_init"); 1070 Bzero(rn_zeros, 3 * max_keylen); 1071 rn_ones = cp = rn_zeros + max_keylen; 1072 addmask_key = cplim = rn_ones + max_keylen; 1073 while (cp < cplim) 1074 *cp++ = -1; 1075 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 1076 panic("rn_init 2"); 1077 } 1078