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 * $FreeBSD$ 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 #define M_DONTWAIT M_NOWAIT 46 #include <sys/domain.h> 47 #else 48 #include <stdlib.h> 49 #endif 50 #include <sys/syslog.h> 51 #include <net/radix.h> 52 #endif 53 54 static int rn_walktree_from __P((struct radix_node_head *h, void *a, 55 void *m, walktree_f_t *f, void *w)); 56 static int rn_walktree __P((struct radix_node_head *, walktree_f_t *, void *)); 57 static struct radix_node 58 *rn_insert __P((void *, struct radix_node_head *, int *, 59 struct radix_node [2])), 60 *rn_newpair __P((void *, int, struct radix_node[2])), 61 *rn_search __P((void *, struct radix_node *)), 62 *rn_search_m __P((void *, struct radix_node *, void *)); 63 64 static int max_keylen; 65 static struct radix_mask *rn_mkfreelist; 66 static struct radix_node_head *mask_rnhead; 67 static char *addmask_key; 68 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 69 static char *rn_zeros, *rn_ones; 70 71 #define rn_masktop (mask_rnhead->rnh_treetop) 72 #undef Bcmp 73 #define Bcmp(a, b, l) \ 74 (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 75 76 static int rn_lexobetter __P((void *m_arg, void *n_arg)); 77 static struct radix_mask * 78 rn_new_radix_mask __P((struct radix_node *tt, 79 struct radix_mask *next)); 80 static int rn_satsifies_leaf __P((char *trial, struct radix_node *leaf, 81 int skip)); 82 83 /* 84 * The data structure for the keys is a radix tree with one way 85 * branching removed. The index rn_bit at an internal node n represents a bit 86 * position to be tested. The tree is arranged so that all descendants 87 * of a node n have keys whose bits all agree up to position rn_bit - 1. 88 * (We say the index of n is rn_bit.) 89 * 90 * There is at least one descendant which has a one bit at position rn_bit, 91 * and at least one with a zero there. 92 * 93 * A route is determined by a pair of key and mask. We require that the 94 * bit-wise logical and of the key and mask to be the key. 95 * We define the index of a route to associated with the mask to be 96 * the first bit number in the mask where 0 occurs (with bit number 0 97 * representing the highest order bit). 98 * 99 * We say a mask is normal if every bit is 0, past the index of the mask. 100 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit, 101 * and m is a normal mask, then the route applies to every descendant of n. 102 * If the index(m) < rn_bit, this implies the trailing last few bits of k 103 * before bit b are all 0, (and hence consequently true of every descendant 104 * of n), so the route applies to all descendants of the node as well. 105 * 106 * Similar logic shows that a non-normal mask m such that 107 * index(m) <= index(n) could potentially apply to many children of n. 108 * Thus, for each non-host route, we attach its mask to a list at an internal 109 * node as high in the tree as we can go. 110 * 111 * The present version of the code makes use of normal routes in short- 112 * circuiting an explict mask and compare operation when testing whether 113 * a key satisfies a normal route, and also in remembering the unique leaf 114 * that governs a subtree. 115 */ 116 117 static struct radix_node * 118 rn_search(v_arg, head) 119 void *v_arg; 120 struct radix_node *head; 121 { 122 register struct radix_node *x; 123 register caddr_t v; 124 125 for (x = head, v = v_arg; x->rn_bit >= 0;) { 126 if (x->rn_bmask & v[x->rn_offset]) 127 x = x->rn_right; 128 else 129 x = x->rn_left; 130 } 131 return (x); 132 } 133 134 static struct radix_node * 135 rn_search_m(v_arg, head, m_arg) 136 struct radix_node *head; 137 void *v_arg, *m_arg; 138 { 139 register struct radix_node *x; 140 register caddr_t v = v_arg, m = m_arg; 141 142 for (x = head; x->rn_bit >= 0;) { 143 if ((x->rn_bmask & m[x->rn_offset]) && 144 (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 int 153 rn_refines(m_arg, n_arg) 154 void *m_arg, *n_arg; 155 { 156 register caddr_t m = m_arg, n = n_arg; 157 register caddr_t lim, lim2 = lim = n + *(u_char *)n; 158 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 159 int masks_are_equal = 1; 160 161 if (longer > 0) 162 lim -= longer; 163 while (n < lim) { 164 if (*n & ~(*m)) 165 return 0; 166 if (*n++ != *m++) 167 masks_are_equal = 0; 168 } 169 while (n < lim2) 170 if (*n++) 171 return 0; 172 if (masks_are_equal && (longer < 0)) 173 for (lim2 = m - longer; m < lim2; ) 174 if (*m++) 175 return 1; 176 return (!masks_are_equal); 177 } 178 179 struct radix_node * 180 rn_lookup(v_arg, m_arg, head) 181 void *v_arg, *m_arg; 182 struct radix_node_head *head; 183 { 184 register struct radix_node *x; 185 caddr_t netmask = 0; 186 187 if (m_arg) { 188 x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_offset); 189 if (x == 0) 190 return (0); 191 netmask = x->rn_key; 192 } 193 x = rn_match(v_arg, head); 194 if (x && netmask) { 195 while (x && x->rn_mask != netmask) 196 x = x->rn_dupedkey; 197 } 198 return x; 199 } 200 201 static int 202 rn_satsifies_leaf(trial, leaf, skip) 203 char *trial; 204 register struct radix_node *leaf; 205 int skip; 206 { 207 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 208 char *cplim; 209 int length = min(*(u_char *)cp, *(u_char *)cp2); 210 211 if (cp3 == 0) 212 cp3 = rn_ones; 213 else 214 length = min(length, *(u_char *)cp3); 215 cplim = cp + length; cp3 += skip; cp2 += skip; 216 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 217 if ((*cp ^ *cp2) & *cp3) 218 return 0; 219 return 1; 220 } 221 222 struct radix_node * 223 rn_match(v_arg, head) 224 void *v_arg; 225 struct radix_node_head *head; 226 { 227 caddr_t v = v_arg; 228 register struct radix_node *t = head->rnh_treetop, *x; 229 register caddr_t cp = v, cp2; 230 caddr_t cplim; 231 struct radix_node *saved_t, *top = t; 232 int off = t->rn_offset, vlen = *(u_char *)cp, matched_off; 233 register int test, b, rn_bit; 234 235 /* 236 * Open code rn_search(v, top) to avoid overhead of extra 237 * subroutine call. 238 */ 239 for (; t->rn_bit >= 0; ) { 240 if (t->rn_bmask & cp[t->rn_offset]) 241 t = t->rn_right; 242 else 243 t = t->rn_left; 244 } 245 /* 246 * See if we match exactly as a host destination 247 * or at least learn how many bits match, for normal mask finesse. 248 * 249 * It doesn't hurt us to limit how many bytes to check 250 * to the length of the mask, since if it matches we had a genuine 251 * match and the leaf we have is the most specific one anyway; 252 * if it didn't match with a shorter length it would fail 253 * with a long one. This wins big for class B&C netmasks which 254 * are probably the most common case... 255 */ 256 if (t->rn_mask) 257 vlen = *(u_char *)t->rn_mask; 258 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 259 for (; cp < cplim; cp++, cp2++) 260 if (*cp != *cp2) 261 goto on1; 262 /* 263 * This extra grot is in case we are explicitly asked 264 * to look up the default. Ugh! 265 * 266 * Never return the root node itself, it seems to cause a 267 * lot of confusion. 268 */ 269 if (t->rn_flags & RNF_ROOT) 270 t = t->rn_dupedkey; 271 return t; 272 on1: 273 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 274 for (b = 7; (test >>= 1) > 0;) 275 b--; 276 matched_off = cp - v; 277 b += matched_off << 3; 278 rn_bit = -1 - b; 279 /* 280 * If there is a host route in a duped-key chain, it will be first. 281 */ 282 if ((saved_t = t)->rn_mask == 0) 283 t = t->rn_dupedkey; 284 for (; t; t = t->rn_dupedkey) 285 /* 286 * Even if we don't match exactly as a host, 287 * we may match if the leaf we wound up at is 288 * a route to a net. 289 */ 290 if (t->rn_flags & RNF_NORMAL) { 291 if (rn_bit <= t->rn_bit) 292 return t; 293 } else if (rn_satsifies_leaf(v, t, matched_off)) 294 return t; 295 t = saved_t; 296 /* start searching up the tree */ 297 do { 298 register struct radix_mask *m; 299 t = t->rn_parent; 300 m = t->rn_mklist; 301 /* 302 * If non-contiguous masks ever become important 303 * we can restore the masking and open coding of 304 * the search and satisfaction test and put the 305 * calculation of "off" back before the "do". 306 */ 307 while (m) { 308 if (m->rm_flags & RNF_NORMAL) { 309 if (rn_bit <= m->rm_bit) 310 return (m->rm_leaf); 311 } else { 312 off = min(t->rn_offset, matched_off); 313 x = rn_search_m(v, t, m->rm_mask); 314 while (x && x->rn_mask != m->rm_mask) 315 x = x->rn_dupedkey; 316 if (x && rn_satsifies_leaf(v, x, off)) 317 return x; 318 } 319 m = m->rm_mklist; 320 } 321 } while (t != top); 322 return 0; 323 } 324 325 #ifdef RN_DEBUG 326 int rn_nodenum; 327 struct radix_node *rn_clist; 328 int rn_saveinfo; 329 int rn_debug = 1; 330 #endif 331 332 static struct radix_node * 333 rn_newpair(v, b, nodes) 334 void *v; 335 int b; 336 struct radix_node nodes[2]; 337 { 338 register struct radix_node *tt = nodes, *t = tt + 1; 339 t->rn_bit = b; 340 t->rn_bmask = 0x80 >> (b & 7); 341 t->rn_left = tt; 342 t->rn_offset = b >> 3; 343 tt->rn_bit = -1; 344 tt->rn_key = (caddr_t)v; 345 tt->rn_parent = t; 346 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 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 if (tt == saved_tt) { 592 struct radix_node *xx = x; 593 /* link in at head of list */ 594 (tt = treenodes)->rn_dupedkey = t; 595 tt->rn_flags = t->rn_flags; 596 tt->rn_parent = x = t->rn_parent; 597 t->rn_parent = tt; /* parent */ 598 if (x->rn_left == t) 599 x->rn_left = tt; 600 else 601 x->rn_right = tt; 602 saved_tt = tt; x = xx; 603 } else { 604 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 605 t->rn_dupedkey = tt; 606 tt->rn_parent = t; /* parent */ 607 if (tt->rn_dupedkey) /* parent */ 608 tt->rn_dupedkey->rn_parent = tt; /* parent */ 609 } 610 #ifdef RN_DEBUG 611 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 612 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 613 #endif 614 tt->rn_key = (caddr_t) v; 615 tt->rn_bit = -1; 616 tt->rn_flags = RNF_ACTIVE; 617 } 618 /* 619 * Put mask in tree. 620 */ 621 if (netmask) { 622 tt->rn_mask = netmask; 623 tt->rn_bit = x->rn_bit; 624 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 625 } 626 t = saved_tt->rn_parent; 627 if (keyduplicated) 628 goto on2; 629 b_leaf = -1 - t->rn_bit; 630 if (t->rn_right == saved_tt) 631 x = t->rn_left; 632 else 633 x = t->rn_right; 634 /* Promote general routes from below */ 635 if (x->rn_bit < 0) { 636 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 637 if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) { 638 *mp = m = rn_new_radix_mask(x, 0); 639 if (m) 640 mp = &m->rm_mklist; 641 } 642 } else if (x->rn_mklist) { 643 /* 644 * Skip over masks whose index is > that of new node 645 */ 646 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 647 if (m->rm_bit >= b_leaf) 648 break; 649 t->rn_mklist = m; *mp = 0; 650 } 651 on2: 652 /* Add new route to highest possible ancestor's list */ 653 if ((netmask == 0) || (b > t->rn_bit )) 654 return tt; /* can't lift at all */ 655 b_leaf = tt->rn_bit; 656 do { 657 x = t; 658 t = t->rn_parent; 659 } while (b <= t->rn_bit && x != top); 660 /* 661 * Search through routes associated with node to 662 * insert new route according to index. 663 * Need same criteria as when sorting dupedkeys to avoid 664 * double loop on deletion. 665 */ 666 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 667 if (m->rm_bit < b_leaf) 668 continue; 669 if (m->rm_bit > b_leaf) 670 break; 671 if (m->rm_flags & RNF_NORMAL) { 672 mmask = m->rm_leaf->rn_mask; 673 if (tt->rn_flags & RNF_NORMAL) { 674 log(LOG_ERR, 675 "Non-unique normal route, mask not entered"); 676 return tt; 677 } 678 } else 679 mmask = m->rm_mask; 680 if (mmask == netmask) { 681 m->rm_refs++; 682 tt->rn_mklist = m; 683 return tt; 684 } 685 if (rn_refines(netmask, mmask) 686 || rn_lexobetter(netmask, mmask)) 687 break; 688 } 689 *mp = rn_new_radix_mask(tt, *mp); 690 return tt; 691 } 692 693 struct radix_node * 694 rn_delete(v_arg, netmask_arg, head) 695 void *v_arg, *netmask_arg; 696 struct radix_node_head *head; 697 { 698 register struct radix_node *t, *p, *x, *tt; 699 struct radix_mask *m, *saved_m, **mp; 700 struct radix_node *dupedkey, *saved_tt, *top; 701 caddr_t v, netmask; 702 int b, head_off, vlen; 703 704 v = v_arg; 705 netmask = netmask_arg; 706 x = head->rnh_treetop; 707 tt = rn_search(v, x); 708 head_off = x->rn_offset; 709 vlen = *(u_char *)v; 710 saved_tt = tt; 711 top = x; 712 if (tt == 0 || 713 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 714 return (0); 715 /* 716 * Delete our route from mask lists. 717 */ 718 if (netmask) { 719 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 720 return (0); 721 netmask = x->rn_key; 722 while (tt->rn_mask != netmask) 723 if ((tt = tt->rn_dupedkey) == 0) 724 return (0); 725 } 726 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 727 goto on1; 728 if (tt->rn_flags & RNF_NORMAL) { 729 if (m->rm_leaf != tt || m->rm_refs > 0) { 730 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 731 return 0; /* dangling ref could cause disaster */ 732 } 733 } else { 734 if (m->rm_mask != tt->rn_mask) { 735 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 736 goto on1; 737 } 738 if (--m->rm_refs >= 0) 739 goto on1; 740 } 741 b = -1 - tt->rn_bit; 742 t = saved_tt->rn_parent; 743 if (b > t->rn_bit) 744 goto on1; /* Wasn't lifted at all */ 745 do { 746 x = t; 747 t = t->rn_parent; 748 } while (b <= t->rn_bit && x != top); 749 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 750 if (m == saved_m) { 751 *mp = m->rm_mklist; 752 MKFree(m); 753 break; 754 } 755 if (m == 0) { 756 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 757 if (tt->rn_flags & RNF_NORMAL) 758 return (0); /* Dangling ref to us */ 759 } 760 on1: 761 /* 762 * Eliminate us from tree 763 */ 764 if (tt->rn_flags & RNF_ROOT) 765 return (0); 766 #ifdef RN_DEBUG 767 /* Get us out of the creation list */ 768 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 769 if (t) t->rn_ybro = tt->rn_ybro; 770 #endif 771 t = tt->rn_parent; 772 dupedkey = saved_tt->rn_dupedkey; 773 if (dupedkey) { 774 /* 775 * at this point, tt is the deletion target and saved_tt 776 * is the head of the dupekey chain 777 */ 778 if (tt == saved_tt) { 779 /* remove from head of chain */ 780 x = dupedkey; x->rn_parent = t; 781 if (t->rn_left == tt) 782 t->rn_left = x; 783 else 784 t->rn_right = x; 785 } else { 786 /* find node in front of tt on the chain */ 787 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 788 p = p->rn_dupedkey; 789 if (p) { 790 p->rn_dupedkey = tt->rn_dupedkey; 791 if (tt->rn_dupedkey) /* parent */ 792 tt->rn_dupedkey->rn_parent = p; 793 /* parent */ 794 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 795 } 796 t = tt + 1; 797 if (t->rn_flags & RNF_ACTIVE) { 798 #ifndef RN_DEBUG 799 *++x = *t; 800 p = t->rn_parent; 801 #else 802 b = t->rn_info; 803 *++x = *t; 804 t->rn_info = b; 805 p = t->rn_parent; 806 #endif 807 if (p->rn_left == t) 808 p->rn_left = x; 809 else 810 p->rn_right = x; 811 x->rn_left->rn_parent = x; 812 x->rn_right->rn_parent = x; 813 } 814 goto out; 815 } 816 if (t->rn_left == tt) 817 x = t->rn_right; 818 else 819 x = t->rn_left; 820 p = t->rn_parent; 821 if (p->rn_right == t) 822 p->rn_right = x; 823 else 824 p->rn_left = x; 825 x->rn_parent = p; 826 /* 827 * Demote routes attached to us. 828 */ 829 if (t->rn_mklist) { 830 if (x->rn_bit >= 0) { 831 for (mp = &x->rn_mklist; (m = *mp);) 832 mp = &m->rm_mklist; 833 *mp = t->rn_mklist; 834 } else { 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 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 839 if (m == x->rn_mklist) { 840 struct radix_mask *mm = m->rm_mklist; 841 x->rn_mklist = 0; 842 if (--(m->rm_refs) < 0) 843 MKFree(m); 844 m = mm; 845 } 846 if (m) 847 log(LOG_ERR, 848 "rn_delete: Orphaned Mask %p at %p\n", 849 (void *)m, (void *)x); 850 } 851 } 852 /* 853 * We may be holding an active internal node in the tree. 854 */ 855 x = tt + 1; 856 if (t != x) { 857 #ifndef RN_DEBUG 858 *t = *x; 859 #else 860 b = t->rn_info; 861 *t = *x; 862 t->rn_info = b; 863 #endif 864 t->rn_left->rn_parent = t; 865 t->rn_right->rn_parent = t; 866 p = x->rn_parent; 867 if (p->rn_left == x) 868 p->rn_left = t; 869 else 870 p->rn_right = t; 871 } 872 out: 873 tt->rn_flags &= ~RNF_ACTIVE; 874 tt[1].rn_flags &= ~RNF_ACTIVE; 875 return (tt); 876 } 877 878 /* 879 * This is the same as rn_walktree() except for the parameters and the 880 * exit. 881 */ 882 static int 883 rn_walktree_from(h, a, m, f, w) 884 struct radix_node_head *h; 885 void *a, *m; 886 walktree_f_t *f; 887 void *w; 888 { 889 int error; 890 struct radix_node *base, *next; 891 u_char *xa = (u_char *)a; 892 u_char *xm = (u_char *)m; 893 register struct radix_node *rn, *last = 0 /* shut up gcc */; 894 int stopping = 0; 895 int lastb; 896 897 /* 898 * rn_search_m is sort-of-open-coded here. 899 */ 900 /* printf("about to search\n"); */ 901 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) { 902 last = rn; 903 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n", 904 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */ 905 if (!(rn->rn_bmask & xm[rn->rn_offset])) { 906 break; 907 } 908 if (rn->rn_bmask & xa[rn->rn_offset]) { 909 rn = rn->rn_right; 910 } else { 911 rn = rn->rn_left; 912 } 913 } 914 /* printf("done searching\n"); */ 915 916 /* 917 * Two cases: either we stepped off the end of our mask, 918 * in which case last == rn, or we reached a leaf, in which 919 * case we want to start from the last node we looked at. 920 * Either way, last is the node we want to start from. 921 */ 922 rn = last; 923 lastb = rn->rn_bit; 924 925 /* printf("rn %p, lastb %d\n", rn, lastb);*/ 926 927 /* 928 * This gets complicated because we may delete the node 929 * while applying the function f to it, so we need to calculate 930 * the successor node in advance. 931 */ 932 while (rn->rn_bit >= 0) 933 rn = rn->rn_left; 934 935 while (!stopping) { 936 /* printf("node %p (%d)\n", rn, rn->rn_bit); */ 937 base = rn; 938 /* If at right child go back up, otherwise, go right */ 939 while (rn->rn_parent->rn_right == rn 940 && !(rn->rn_flags & RNF_ROOT)) { 941 rn = rn->rn_parent; 942 943 /* if went up beyond last, stop */ 944 if (rn->rn_bit < lastb) { 945 stopping = 1; 946 /* printf("up too far\n"); */ 947 } 948 } 949 950 /* Find the next *leaf* since next node might vanish, too */ 951 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 952 rn = rn->rn_left; 953 next = rn; 954 /* Process leaves */ 955 while ((rn = base) != 0) { 956 base = rn->rn_dupedkey; 957 /* printf("leaf %p\n", rn); */ 958 if (!(rn->rn_flags & RNF_ROOT) 959 && (error = (*f)(rn, w))) 960 return (error); 961 } 962 rn = next; 963 964 if (rn->rn_flags & RNF_ROOT) { 965 /* printf("root, stopping"); */ 966 stopping = 1; 967 } 968 969 } 970 return 0; 971 } 972 973 static int 974 rn_walktree(h, f, w) 975 struct radix_node_head *h; 976 walktree_f_t *f; 977 void *w; 978 { 979 int error; 980 struct radix_node *base, *next; 981 register struct radix_node *rn = h->rnh_treetop; 982 /* 983 * This gets complicated because we may delete the node 984 * while applying the function f to it, so we need to calculate 985 * the successor node in advance. 986 */ 987 /* First time through node, go left */ 988 while (rn->rn_bit >= 0) 989 rn = rn->rn_left; 990 for (;;) { 991 base = rn; 992 /* If at right child go back up, otherwise, go right */ 993 while (rn->rn_parent->rn_right == rn 994 && (rn->rn_flags & RNF_ROOT) == 0) 995 rn = rn->rn_parent; 996 /* Find the next *leaf* since next node might vanish, too */ 997 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 998 rn = rn->rn_left; 999 next = rn; 1000 /* Process leaves */ 1001 while ((rn = base)) { 1002 base = rn->rn_dupedkey; 1003 if (!(rn->rn_flags & RNF_ROOT) 1004 && (error = (*f)(rn, w))) 1005 return (error); 1006 } 1007 rn = next; 1008 if (rn->rn_flags & RNF_ROOT) 1009 return (0); 1010 } 1011 /* NOTREACHED */ 1012 } 1013 1014 int 1015 rn_inithead(head, off) 1016 void **head; 1017 int off; 1018 { 1019 register struct radix_node_head *rnh; 1020 register struct radix_node *t, *tt, *ttt; 1021 if (*head) 1022 return (1); 1023 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 1024 if (rnh == 0) 1025 return (0); 1026 Bzero(rnh, sizeof (*rnh)); 1027 *head = rnh; 1028 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1029 ttt = rnh->rnh_nodes + 2; 1030 t->rn_right = ttt; 1031 t->rn_parent = t; 1032 tt = t->rn_left; 1033 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 1034 tt->rn_bit = -1 - off; 1035 *ttt = *tt; 1036 ttt->rn_key = rn_ones; 1037 rnh->rnh_addaddr = rn_addroute; 1038 rnh->rnh_deladdr = rn_delete; 1039 rnh->rnh_matchaddr = rn_match; 1040 rnh->rnh_lookup = rn_lookup; 1041 rnh->rnh_walktree = rn_walktree; 1042 rnh->rnh_walktree_from = rn_walktree_from; 1043 rnh->rnh_treetop = t; 1044 return (1); 1045 } 1046 1047 void 1048 rn_init() 1049 { 1050 char *cp, *cplim; 1051 #ifdef _KERNEL 1052 struct domain *dom; 1053 1054 for (dom = domains; dom; dom = dom->dom_next) 1055 if (dom->dom_maxrtkey > max_keylen) 1056 max_keylen = dom->dom_maxrtkey; 1057 #endif 1058 if (max_keylen == 0) { 1059 log(LOG_ERR, 1060 "rn_init: radix functions require max_keylen be set\n"); 1061 return; 1062 } 1063 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1064 if (rn_zeros == NULL) 1065 panic("rn_init"); 1066 Bzero(rn_zeros, 3 * max_keylen); 1067 rn_ones = cp = rn_zeros + max_keylen; 1068 addmask_key = cplim = rn_ones + max_keylen; 1069 while (cp < cplim) 1070 *cp++ = -1; 1071 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 1072 panic("rn_init 2"); 1073 } 1074