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sys/net/radix.c
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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 tt->rn_mklist = t->rn_mklist = 0; 348 #ifdef RN_DEBUG 349 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 350 tt->rn_twin = t; 351 tt->rn_ybro = rn_clist; 352 rn_clist = tt; 353 #endif 354 return t; 355 } 356 357 static struct radix_node * 358 rn_insert(v_arg, head, dupentry, nodes) 359 void *v_arg; 360 struct radix_node_head *head; 361 int *dupentry; 362 struct radix_node nodes[2]; 363 { 364 caddr_t v = v_arg; 365 struct radix_node *top = head->rnh_treetop; 366 int head_off = top->rn_offset, vlen = (int)*((u_char *)v); 367 register struct radix_node *t = rn_search(v_arg, top); 368 register caddr_t cp = v + head_off; 369 register int b; 370 struct radix_node *tt; 371 /* 372 * Find first bit at which v and t->rn_key differ 373 */ 374 { 375 register caddr_t cp2 = t->rn_key + head_off; 376 register int cmp_res; 377 caddr_t cplim = v + vlen; 378 379 while (cp < cplim) 380 if (*cp2++ != *cp++) 381 goto on1; 382 *dupentry = 1; 383 return t; 384 on1: 385 *dupentry = 0; 386 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 387 for (b = (cp - v) << 3; cmp_res; b--) 388 cmp_res >>= 1; 389 } 390 { 391 register struct radix_node *p, *x = top; 392 cp = v; 393 do { 394 p = x; 395 if (cp[x->rn_offset] & x->rn_bmask) 396 x = x->rn_right; 397 else 398 x = x->rn_left; 399 } while (b > (unsigned) x->rn_bit); 400 /* x->rn_bit < b && x->rn_bit >= 0 */ 401 #ifdef RN_DEBUG 402 if (rn_debug) 403 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 404 #endif 405 t = rn_newpair(v_arg, b, nodes); 406 tt = t->rn_left; 407 if ((cp[p->rn_offset] & p->rn_bmask) == 0) 408 p->rn_left = t; 409 else 410 p->rn_right = t; 411 x->rn_parent = t; 412 t->rn_parent = p; /* frees x, p as temp vars below */ 413 if ((cp[t->rn_offset] & t->rn_bmask) == 0) { 414 t->rn_right = x; 415 } else { 416 t->rn_right = tt; 417 t->rn_left = x; 418 } 419 #ifdef RN_DEBUG 420 if (rn_debug) 421 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 422 #endif 423 } 424 return (tt); 425 } 426 427 struct radix_node * 428 rn_addmask(n_arg, search, skip) 429 int search, skip; 430 void *n_arg; 431 { 432 caddr_t netmask = (caddr_t)n_arg; 433 register struct radix_node *x; 434 register caddr_t cp, cplim; 435 register int b = 0, mlen, j; 436 int maskduplicated, m0, isnormal; 437 struct radix_node *saved_x; 438 static int last_zeroed = 0; 439 440 if ((mlen = *(u_char *)netmask) > max_keylen) 441 mlen = max_keylen; 442 if (skip == 0) 443 skip = 1; 444 if (mlen <= skip) 445 return (mask_rnhead->rnh_nodes); 446 if (skip > 1) 447 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 448 if ((m0 = mlen) > skip) 449 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 450 /* 451 * Trim trailing zeroes. 452 */ 453 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 454 cp--; 455 mlen = cp - addmask_key; 456 if (mlen <= skip) { 457 if (m0 >= last_zeroed) 458 last_zeroed = mlen; 459 return (mask_rnhead->rnh_nodes); 460 } 461 if (m0 < last_zeroed) 462 Bzero(addmask_key + m0, last_zeroed - m0); 463 *addmask_key = last_zeroed = mlen; 464 x = rn_search(addmask_key, rn_masktop); 465 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 466 x = 0; 467 if (x || search) 468 return (x); 469 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 470 if ((saved_x = x) == 0) 471 return (0); 472 Bzero(x, max_keylen + 2 * sizeof (*x)); 473 netmask = cp = (caddr_t)(x + 2); 474 Bcopy(addmask_key, cp, mlen); 475 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 476 if (maskduplicated) { 477 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 478 Free(saved_x); 479 return (x); 480 } 481 /* 482 * Calculate index of mask, and check for normalcy. 483 */ 484 cplim = netmask + mlen; isnormal = 1; 485 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 486 cp++; 487 if (cp != cplim) { 488 for (j = 0x80; (j & *cp) != 0; j >>= 1) 489 b++; 490 if (*cp != normal_chars[b] || cp != (cplim - 1)) 491 isnormal = 0; 492 } 493 b += (cp - netmask) << 3; 494 x->rn_bit = -1 - b; 495 if (isnormal) 496 x->rn_flags |= RNF_NORMAL; 497 return (x); 498 } 499 500 static int /* XXX: arbitrary ordering for non-contiguous masks */ 501 rn_lexobetter(m_arg, n_arg) 502 void *m_arg, *n_arg; 503 { 504 register u_char *mp = m_arg, *np = n_arg, *lim; 505 506 if (*mp > *np) 507 return 1; /* not really, but need to check longer one first */ 508 if (*mp == *np) 509 for (lim = mp + *mp; mp < lim;) 510 if (*mp++ > *np++) 511 return 1; 512 return 0; 513 } 514 515 static struct radix_mask * 516 rn_new_radix_mask(tt, next) 517 register struct radix_node *tt; 518 register struct radix_mask *next; 519 { 520 register struct radix_mask *m; 521 522 MKGet(m); 523 if (m == 0) { 524 log(LOG_ERR, "Mask for route not entered\n"); 525 return (0); 526 } 527 Bzero(m, sizeof *m); 528 m->rm_bit = tt->rn_bit; 529 m->rm_flags = tt->rn_flags; 530 if (tt->rn_flags & RNF_NORMAL) 531 m->rm_leaf = tt; 532 else 533 m->rm_mask = tt->rn_mask; 534 m->rm_mklist = next; 535 tt->rn_mklist = m; 536 return m; 537 } 538 539 struct radix_node * 540 rn_addroute(v_arg, n_arg, head, treenodes) 541 void *v_arg, *n_arg; 542 struct radix_node_head *head; 543 struct radix_node treenodes[2]; 544 { 545 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 546 register struct radix_node *t, *x = 0, *tt; 547 struct radix_node *saved_tt, *top = head->rnh_treetop; 548 short b = 0, b_leaf = 0; 549 int keyduplicated; 550 caddr_t mmask; 551 struct radix_mask *m, **mp; 552 553 /* 554 * In dealing with non-contiguous masks, there may be 555 * many different routes which have the same mask. 556 * We will find it useful to have a unique pointer to 557 * the mask to speed avoiding duplicate references at 558 * nodes and possibly save time in calculating indices. 559 */ 560 if (netmask) { 561 if ((x = rn_addmask(netmask, 0, top->rn_offset)) == 0) 562 return (0); 563 b_leaf = x->rn_bit; 564 b = -1 - x->rn_bit; 565 netmask = x->rn_key; 566 } 567 /* 568 * Deal with duplicated keys: attach node to previous instance 569 */ 570 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 571 if (keyduplicated) { 572 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 573 if (tt->rn_mask == netmask) 574 return (0); 575 if (netmask == 0 || 576 (tt->rn_mask && 577 ((b_leaf < tt->rn_bit) /* index(netmask) > node */ 578 || rn_refines(netmask, tt->rn_mask) 579 || rn_lexobetter(netmask, tt->rn_mask)))) 580 break; 581 } 582 /* 583 * If the mask is not duplicated, we wouldn't 584 * find it among possible duplicate key entries 585 * anyway, so the above test doesn't hurt. 586 * 587 * We sort the masks for a duplicated key the same way as 588 * in a masklist -- most specific to least specific. 589 * This may require the unfortunate nuisance of relocating 590 * the head of the list. 591 */ 592 if (tt == saved_tt) { 593 struct radix_node *xx = x; 594 /* link in at head of list */ 595 (tt = treenodes)->rn_dupedkey = t; 596 tt->rn_flags = t->rn_flags; 597 tt->rn_parent = x = t->rn_parent; 598 t->rn_parent = tt; /* parent */ 599 if (x->rn_left == t) 600 x->rn_left = tt; 601 else 602 x->rn_right = tt; 603 saved_tt = tt; x = xx; 604 } else { 605 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 606 t->rn_dupedkey = tt; 607 tt->rn_parent = t; /* parent */ 608 if (tt->rn_dupedkey) /* parent */ 609 tt->rn_dupedkey->rn_parent = tt; /* parent */ 610 } 611 #ifdef RN_DEBUG 612 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 613 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 614 #endif 615 tt->rn_key = (caddr_t) v; 616 tt->rn_bit = -1; 617 tt->rn_flags = RNF_ACTIVE; 618 } 619 /* 620 * Put mask in tree. 621 */ 622 if (netmask) { 623 tt->rn_mask = netmask; 624 tt->rn_bit = x->rn_bit; 625 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 626 } 627 t = saved_tt->rn_parent; 628 if (keyduplicated) 629 goto on2; 630 b_leaf = -1 - t->rn_bit; 631 if (t->rn_right == saved_tt) 632 x = t->rn_left; 633 else 634 x = t->rn_right; 635 /* Promote general routes from below */ 636 if (x->rn_bit < 0) { 637 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 638 if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) { 639 *mp = m = rn_new_radix_mask(x, 0); 640 if (m) 641 mp = &m->rm_mklist; 642 } 643 } else if (x->rn_mklist) { 644 /* 645 * Skip over masks whose index is > that of new node 646 */ 647 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 648 if (m->rm_bit >= b_leaf) 649 break; 650 t->rn_mklist = m; *mp = 0; 651 } 652 on2: 653 /* Add new route to highest possible ancestor's list */ 654 if ((netmask == 0) || (b > t->rn_bit )) 655 return tt; /* can't lift at all */ 656 b_leaf = tt->rn_bit; 657 do { 658 x = t; 659 t = t->rn_parent; 660 } while (b <= t->rn_bit && x != top); 661 /* 662 * Search through routes associated with node to 663 * insert new route according to index. 664 * Need same criteria as when sorting dupedkeys to avoid 665 * double loop on deletion. 666 */ 667 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 668 if (m->rm_bit < b_leaf) 669 continue; 670 if (m->rm_bit > b_leaf) 671 break; 672 if (m->rm_flags & RNF_NORMAL) { 673 mmask = m->rm_leaf->rn_mask; 674 if (tt->rn_flags & RNF_NORMAL) { 675 log(LOG_ERR, 676 "Non-unique normal route, mask not entered\n"); 677 return tt; 678 } 679 } else 680 mmask = m->rm_mask; 681 if (mmask == netmask) { 682 m->rm_refs++; 683 tt->rn_mklist = m; 684 return tt; 685 } 686 if (rn_refines(netmask, mmask) 687 || rn_lexobetter(netmask, mmask)) 688 break; 689 } 690 *mp = rn_new_radix_mask(tt, *mp); 691 return tt; 692 } 693 694 struct radix_node * 695 rn_delete(v_arg, netmask_arg, head) 696 void *v_arg, *netmask_arg; 697 struct radix_node_head *head; 698 { 699 register struct radix_node *t, *p, *x, *tt; 700 struct radix_mask *m, *saved_m, **mp; 701 struct radix_node *dupedkey, *saved_tt, *top; 702 caddr_t v, netmask; 703 int b, head_off, vlen; 704 705 v = v_arg; 706 netmask = netmask_arg; 707 x = head->rnh_treetop; 708 tt = rn_search(v, x); 709 head_off = x->rn_offset; 710 vlen = *(u_char *)v; 711 saved_tt = tt; 712 top = x; 713 if (tt == 0 || 714 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 715 return (0); 716 /* 717 * Delete our route from mask lists. 718 */ 719 if (netmask) { 720 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 721 return (0); 722 netmask = x->rn_key; 723 while (tt->rn_mask != netmask) 724 if ((tt = tt->rn_dupedkey) == 0) 725 return (0); 726 } 727 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 728 goto on1; 729 if (tt->rn_flags & RNF_NORMAL) { 730 if (m->rm_leaf != tt || m->rm_refs > 0) { 731 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 732 return 0; /* dangling ref could cause disaster */ 733 } 734 } else { 735 if (m->rm_mask != tt->rn_mask) { 736 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 737 goto on1; 738 } 739 if (--m->rm_refs >= 0) 740 goto on1; 741 } 742 b = -1 - tt->rn_bit; 743 t = saved_tt->rn_parent; 744 if (b > t->rn_bit) 745 goto on1; /* Wasn't lifted at all */ 746 do { 747 x = t; 748 t = t->rn_parent; 749 } while (b <= t->rn_bit && x != top); 750 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 751 if (m == saved_m) { 752 *mp = m->rm_mklist; 753 MKFree(m); 754 break; 755 } 756 if (m == 0) { 757 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 758 if (tt->rn_flags & RNF_NORMAL) 759 return (0); /* Dangling ref to us */ 760 } 761 on1: 762 /* 763 * Eliminate us from tree 764 */ 765 if (tt->rn_flags & RNF_ROOT) 766 return (0); 767 #ifdef RN_DEBUG 768 /* Get us out of the creation list */ 769 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 770 if (t) t->rn_ybro = tt->rn_ybro; 771 #endif 772 t = tt->rn_parent; 773 dupedkey = saved_tt->rn_dupedkey; 774 if (dupedkey) { 775 /* 776 * at this point, tt is the deletion target and saved_tt 777 * is the head of the dupekey chain 778 */ 779 if (tt == saved_tt) { 780 /* remove from head of chain */ 781 x = dupedkey; x->rn_parent = t; 782 if (t->rn_left == tt) 783 t->rn_left = x; 784 else 785 t->rn_right = x; 786 } else { 787 /* find node in front of tt on the chain */ 788 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 789 p = p->rn_dupedkey; 790 if (p) { 791 p->rn_dupedkey = tt->rn_dupedkey; 792 if (tt->rn_dupedkey) /* parent */ 793 tt->rn_dupedkey->rn_parent = p; 794 /* parent */ 795 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 796 } 797 t = tt + 1; 798 if (t->rn_flags & RNF_ACTIVE) { 799 #ifndef RN_DEBUG 800 *++x = *t; 801 p = t->rn_parent; 802 #else 803 b = t->rn_info; 804 *++x = *t; 805 t->rn_info = b; 806 p = t->rn_parent; 807 #endif 808 if (p->rn_left == t) 809 p->rn_left = x; 810 else 811 p->rn_right = x; 812 x->rn_left->rn_parent = x; 813 x->rn_right->rn_parent = x; 814 } 815 goto out; 816 } 817 if (t->rn_left == tt) 818 x = t->rn_right; 819 else 820 x = t->rn_left; 821 p = t->rn_parent; 822 if (p->rn_right == t) 823 p->rn_right = x; 824 else 825 p->rn_left = x; 826 x->rn_parent = p; 827 /* 828 * Demote routes attached to us. 829 */ 830 if (t->rn_mklist) { 831 if (x->rn_bit >= 0) { 832 for (mp = &x->rn_mklist; (m = *mp);) 833 mp = &m->rm_mklist; 834 *mp = t->rn_mklist; 835 } else { 836 /* If there are any key,mask pairs in a sibling 837 duped-key chain, some subset will appear sorted 838 in the same order attached to our mklist */ 839 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 840 if (m == x->rn_mklist) { 841 struct radix_mask *mm = m->rm_mklist; 842 x->rn_mklist = 0; 843 if (--(m->rm_refs) < 0) 844 MKFree(m); 845 m = mm; 846 } 847 if (m) 848 log(LOG_ERR, 849 "rn_delete: Orphaned Mask %p at %p\n", 850 (void *)m, (void *)x); 851 } 852 } 853 /* 854 * We may be holding an active internal node in the tree. 855 */ 856 x = tt + 1; 857 if (t != x) { 858 #ifndef RN_DEBUG 859 *t = *x; 860 #else 861 b = t->rn_info; 862 *t = *x; 863 t->rn_info = b; 864 #endif 865 t->rn_left->rn_parent = t; 866 t->rn_right->rn_parent = t; 867 p = x->rn_parent; 868 if (p->rn_left == x) 869 p->rn_left = t; 870 else 871 p->rn_right = t; 872 } 873 out: 874 tt->rn_flags &= ~RNF_ACTIVE; 875 tt[1].rn_flags &= ~RNF_ACTIVE; 876 return (tt); 877 } 878 879 /* 880 * This is the same as rn_walktree() except for the parameters and the 881 * exit. 882 */ 883 static int 884 rn_walktree_from(h, a, m, f, w) 885 struct radix_node_head *h; 886 void *a, *m; 887 walktree_f_t *f; 888 void *w; 889 { 890 int error; 891 struct radix_node *base, *next; 892 u_char *xa = (u_char *)a; 893 u_char *xm = (u_char *)m; 894 register struct radix_node *rn, *last = 0 /* shut up gcc */; 895 int stopping = 0; 896 int lastb; 897 898 /* 899 * rn_search_m is sort-of-open-coded here. 900 */ 901 /* printf("about to search\n"); */ 902 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) { 903 last = rn; 904 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n", 905 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */ 906 if (!(rn->rn_bmask & xm[rn->rn_offset])) { 907 break; 908 } 909 if (rn->rn_bmask & xa[rn->rn_offset]) { 910 rn = rn->rn_right; 911 } else { 912 rn = rn->rn_left; 913 } 914 } 915 /* printf("done searching\n"); */ 916 917 /* 918 * Two cases: either we stepped off the end of our mask, 919 * in which case last == rn, or we reached a leaf, in which 920 * case we want to start from the last node we looked at. 921 * Either way, last is the node we want to start from. 922 */ 923 rn = last; 924 lastb = rn->rn_bit; 925 926 /* printf("rn %p, lastb %d\n", rn, lastb);*/ 927 928 /* 929 * This gets complicated because we may delete the node 930 * while applying the function f to it, so we need to calculate 931 * the successor node in advance. 932 */ 933 while (rn->rn_bit >= 0) 934 rn = rn->rn_left; 935 936 while (!stopping) { 937 /* printf("node %p (%d)\n", rn, rn->rn_bit); */ 938 base = rn; 939 /* If at right child go back up, otherwise, go right */ 940 while (rn->rn_parent->rn_right == rn 941 && !(rn->rn_flags & RNF_ROOT)) { 942 rn = rn->rn_parent; 943 944 /* if went up beyond last, stop */ 945 if (rn->rn_bit < lastb) { 946 stopping = 1; 947 /* printf("up too far\n"); */ 948 } 949 } 950 951 /* Find the next *leaf* since next node might vanish, too */ 952 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 953 rn = rn->rn_left; 954 next = rn; 955 /* Process leaves */ 956 while ((rn = base) != 0) { 957 base = rn->rn_dupedkey; 958 /* printf("leaf %p\n", rn); */ 959 if (!(rn->rn_flags & RNF_ROOT) 960 && (error = (*f)(rn, w))) 961 return (error); 962 } 963 rn = next; 964 965 if (rn->rn_flags & RNF_ROOT) { 966 /* printf("root, stopping"); */ 967 stopping = 1; 968 } 969 970 } 971 return 0; 972 } 973 974 static int 975 rn_walktree(h, f, w) 976 struct radix_node_head *h; 977 walktree_f_t *f; 978 void *w; 979 { 980 int error; 981 struct radix_node *base, *next; 982 register struct radix_node *rn = h->rnh_treetop; 983 /* 984 * This gets complicated because we may delete the node 985 * while applying the function f to it, so we need to calculate 986 * the successor node in advance. 987 */ 988 /* First time through node, go left */ 989 while (rn->rn_bit >= 0) 990 rn = rn->rn_left; 991 for (;;) { 992 base = rn; 993 /* If at right child go back up, otherwise, go right */ 994 while (rn->rn_parent->rn_right == rn 995 && (rn->rn_flags & RNF_ROOT) == 0) 996 rn = rn->rn_parent; 997 /* Find the next *leaf* since next node might vanish, too */ 998 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 999 rn = rn->rn_left; 1000 next = rn; 1001 /* Process leaves */ 1002 while ((rn = base)) { 1003 base = rn->rn_dupedkey; 1004 if (!(rn->rn_flags & RNF_ROOT) 1005 && (error = (*f)(rn, w))) 1006 return (error); 1007 } 1008 rn = next; 1009 if (rn->rn_flags & RNF_ROOT) 1010 return (0); 1011 } 1012 /* NOTREACHED */ 1013 } 1014 1015 int 1016 rn_inithead(head, off) 1017 void **head; 1018 int off; 1019 { 1020 register struct radix_node_head *rnh; 1021 register struct radix_node *t, *tt, *ttt; 1022 if (*head) 1023 return (1); 1024 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 1025 if (rnh == 0) 1026 return (0); 1027 Bzero(rnh, sizeof (*rnh)); 1028 *head = rnh; 1029 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1030 ttt = rnh->rnh_nodes + 2; 1031 t->rn_right = ttt; 1032 t->rn_parent = t; 1033 tt = t->rn_left; 1034 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 1035 tt->rn_bit = -1 - off; 1036 *ttt = *tt; 1037 ttt->rn_key = rn_ones; 1038 rnh->rnh_addaddr = rn_addroute; 1039 rnh->rnh_deladdr = rn_delete; 1040 rnh->rnh_matchaddr = rn_match; 1041 rnh->rnh_lookup = rn_lookup; 1042 rnh->rnh_walktree = rn_walktree; 1043 rnh->rnh_walktree_from = rn_walktree_from; 1044 rnh->rnh_treetop = t; 1045 return (1); 1046 } 1047 1048 void 1049 rn_init() 1050 { 1051 char *cp, *cplim; 1052 #ifdef _KERNEL 1053 struct domain *dom; 1054 1055 for (dom = domains; dom; dom = dom->dom_next) 1056 if (dom->dom_maxrtkey > max_keylen) 1057 max_keylen = dom->dom_maxrtkey; 1058 #endif 1059 if (max_keylen == 0) { 1060 log(LOG_ERR, 1061 "rn_init: radix functions require max_keylen be set\n"); 1062 return; 1063 } 1064 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1065 if (rn_zeros == NULL) 1066 panic("rn_init"); 1067 Bzero(rn_zeros, 3 * max_keylen); 1068 rn_ones = cp = rn_zeros + max_keylen; 1069 addmask_key = cplim = rn_ones + max_keylen; 1070 while (cp < cplim) 1071 *cp++ = -1; 1072 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 1073 panic("rn_init 2"); 1074 }
Cache object: 5fbb426fa571f7e95c7d3c758b39b580
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