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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: src/sys/net/radix.c,v 1.11.4.1 1999/09/05 08:17:56 peter Exp $ 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 struct radix_node * 55 rn_lookup __P((void *v_arg, void *m_arg, 56 struct radix_node_head *head)); 57 static int rn_walktree_from __P((struct radix_node_head *h, void *a, 58 void *m, walktree_f_t *f, void *w)); 59 static int rn_walktree __P((struct radix_node_head *, walktree_f_t *, void *)); 60 static struct radix_node 61 *rn_delete __P((void *, void *, struct radix_node_head *)), 62 *rn_insert __P((void *, struct radix_node_head *, int *, 63 struct radix_node [2])), 64 *rn_newpair __P((void *, int, struct radix_node[2])), 65 *rn_search __P((void *, struct radix_node *)), 66 *rn_search_m __P((void *, struct radix_node *, void *)); 67 68 static int max_keylen; 69 static struct radix_mask *rn_mkfreelist; 70 static struct radix_node_head *mask_rnhead; 71 static char *addmask_key; 72 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 73 static char *rn_zeros, *rn_ones; 74 75 #define rn_masktop (mask_rnhead->rnh_treetop) 76 #undef Bcmp 77 #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 78 79 static int rn_lexobetter __P((void *m_arg, void *n_arg)); 80 static struct radix_mask * 81 rn_new_radix_mask __P((struct radix_node *tt, 82 struct radix_mask *next)); 83 static int rn_satsifies_leaf __P((char *trial, struct radix_node *leaf, 84 int skip)); 85 86 /* 87 * The data structure for the keys is a radix tree with one way 88 * branching removed. The index rn_b at an internal node n represents a bit 89 * position to be tested. The tree is arranged so that all descendants 90 * of a node n have keys whose bits all agree up to position rn_b - 1. 91 * (We say the index of n is rn_b.) 92 * 93 * There is at least one descendant which has a one bit at position rn_b, 94 * and at least one with a zero there. 95 * 96 * A route is determined by a pair of key and mask. We require that the 97 * bit-wise logical and of the key and mask to be the key. 98 * We define the index of a route to associated with the mask to be 99 * the first bit number in the mask where 0 occurs (with bit number 0 100 * representing the highest order bit). 101 * 102 * We say a mask is normal if every bit is 0, past the index of the mask. 103 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 104 * and m is a normal mask, then the route applies to every descendant of n. 105 * If the index(m) < rn_b, this implies the trailing last few bits of k 106 * before bit b are all 0, (and hence consequently true of every descendant 107 * of n), so the route applies to all descendants of the node as well. 108 * 109 * Similar logic shows that a non-normal mask m such that 110 * index(m) <= index(n) could potentially apply to many children of n. 111 * Thus, for each non-host route, we attach its mask to a list at an internal 112 * node as high in the tree as we can go. 113 * 114 * The present version of the code makes use of normal routes in short- 115 * circuiting an explict mask and compare operation when testing whether 116 * a key satisfies a normal route, and also in remembering the unique leaf 117 * that governs a subtree. 118 */ 119 120 static struct radix_node * 121 rn_search(v_arg, head) 122 void *v_arg; 123 struct radix_node *head; 124 { 125 register struct radix_node *x; 126 register caddr_t v; 127 128 for (x = head, v = v_arg; x->rn_b >= 0;) { 129 if (x->rn_bmask & v[x->rn_off]) 130 x = x->rn_r; 131 else 132 x = x->rn_l; 133 } 134 return (x); 135 }; 136 137 static struct radix_node * 138 rn_search_m(v_arg, head, m_arg) 139 struct radix_node *head; 140 void *v_arg, *m_arg; 141 { 142 register struct radix_node *x; 143 register caddr_t v = v_arg, m = m_arg; 144 145 for (x = head; x->rn_b >= 0;) { 146 if ((x->rn_bmask & m[x->rn_off]) && 147 (x->rn_bmask & v[x->rn_off])) 148 x = x->rn_r; 149 else 150 x = x->rn_l; 151 } 152 return x; 153 }; 154 155 int 156 rn_refines(m_arg, n_arg) 157 void *m_arg, *n_arg; 158 { 159 register caddr_t m = m_arg, n = n_arg; 160 register caddr_t lim, lim2 = lim = n + *(u_char *)n; 161 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 162 int masks_are_equal = 1; 163 164 if (longer > 0) 165 lim -= longer; 166 while (n < lim) { 167 if (*n & ~(*m)) 168 return 0; 169 if (*n++ != *m++) 170 masks_are_equal = 0; 171 } 172 while (n < lim2) 173 if (*n++) 174 return 0; 175 if (masks_are_equal && (longer < 0)) 176 for (lim2 = m - longer; m < lim2; ) 177 if (*m++) 178 return 1; 179 return (!masks_are_equal); 180 } 181 182 struct radix_node * 183 rn_lookup(v_arg, m_arg, head) 184 void *v_arg, *m_arg; 185 struct radix_node_head *head; 186 { 187 register struct radix_node *x; 188 caddr_t netmask = 0; 189 190 if (m_arg) { 191 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 192 return (0); 193 netmask = x->rn_key; 194 } 195 x = rn_match(v_arg, head); 196 if (x && netmask) { 197 while (x && x->rn_mask != netmask) 198 x = x->rn_dupedkey; 199 } 200 return x; 201 } 202 203 static int 204 rn_satsifies_leaf(trial, leaf, skip) 205 char *trial; 206 register struct radix_node *leaf; 207 int skip; 208 { 209 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 210 char *cplim; 211 int length = min(*(u_char *)cp, *(u_char *)cp2); 212 213 if (cp3 == 0) 214 cp3 = rn_ones; 215 else 216 length = min(length, *(u_char *)cp3); 217 cplim = cp + length; cp3 += skip; cp2 += skip; 218 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 219 if ((*cp ^ *cp2) & *cp3) 220 return 0; 221 return 1; 222 } 223 224 struct radix_node * 225 rn_match(v_arg, head) 226 void *v_arg; 227 struct radix_node_head *head; 228 { 229 caddr_t v = v_arg; 230 register struct radix_node *t = head->rnh_treetop, *x; 231 register caddr_t cp = v, cp2; 232 caddr_t cplim; 233 struct radix_node *saved_t, *top = t; 234 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 235 register int test, b, rn_b; 236 237 /* 238 * Open code rn_search(v, top) to avoid overhead of extra 239 * subroutine call. 240 */ 241 for (; t->rn_b >= 0; ) { 242 if (t->rn_bmask & cp[t->rn_off]) 243 t = t->rn_r; 244 else 245 t = t->rn_l; 246 } 247 /* 248 * See if we match exactly as a host destination 249 * or at least learn how many bits match, for normal mask finesse. 250 * 251 * It doesn't hurt us to limit how many bytes to check 252 * to the length of the mask, since if it matches we had a genuine 253 * match and the leaf we have is the most specific one anyway; 254 * if it didn't match with a shorter length it would fail 255 * with a long one. This wins big for class B&C netmasks which 256 * are probably the most common case... 257 */ 258 if (t->rn_mask) 259 vlen = *(u_char *)t->rn_mask; 260 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 261 for (; cp < cplim; cp++, cp2++) 262 if (*cp != *cp2) 263 goto on1; 264 /* 265 * This extra grot is in case we are explicitly asked 266 * to look up the default. Ugh! 267 */ 268 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 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_b = -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_b <= t->rn_b) 291 return t; 292 } else if (rn_satsifies_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_p; 299 m = t->rn_mklist; 300 if (m) { 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 do { 308 if (m->rm_flags & RNF_NORMAL) { 309 if (rn_b <= m->rm_b) 310 return (m->rm_leaf); 311 } else { 312 off = min(t->rn_off, 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 } while (m); 321 } 322 } while (t != top); 323 return 0; 324 }; 325 326 #ifdef RN_DEBUG 327 int rn_nodenum; 328 struct radix_node *rn_clist; 329 int rn_saveinfo; 330 int rn_debug = 1; 331 #endif 332 333 static struct radix_node * 334 rn_newpair(v, b, nodes) 335 void *v; 336 int b; 337 struct radix_node nodes[2]; 338 { 339 register struct radix_node *tt = nodes, *t = tt + 1; 340 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 341 t->rn_l = tt; t->rn_off = b >> 3; 342 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 343 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 344 #ifdef RN_DEBUG 345 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 346 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 347 #endif 348 return t; 349 } 350 351 static struct radix_node * 352 rn_insert(v_arg, head, dupentry, nodes) 353 void *v_arg; 354 struct radix_node_head *head; 355 int *dupentry; 356 struct radix_node nodes[2]; 357 { 358 caddr_t v = v_arg; 359 struct radix_node *top = head->rnh_treetop; 360 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 361 register struct radix_node *t = rn_search(v_arg, top); 362 register caddr_t cp = v + head_off; 363 register int b; 364 struct radix_node *tt; 365 /* 366 * Find first bit at which v and t->rn_key differ 367 */ 368 { 369 register caddr_t cp2 = t->rn_key + head_off; 370 register int cmp_res; 371 caddr_t cplim = v + vlen; 372 373 while (cp < cplim) 374 if (*cp2++ != *cp++) 375 goto on1; 376 *dupentry = 1; 377 return t; 378 on1: 379 *dupentry = 0; 380 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 381 for (b = (cp - v) << 3; cmp_res; b--) 382 cmp_res >>= 1; 383 } 384 { 385 register struct radix_node *p, *x = top; 386 cp = v; 387 do { 388 p = x; 389 if (cp[x->rn_off] & x->rn_bmask) 390 x = x->rn_r; 391 else x = x->rn_l; 392 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 393 #ifdef RN_DEBUG 394 if (rn_debug) 395 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 396 #endif 397 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 398 if ((cp[p->rn_off] & p->rn_bmask) == 0) 399 p->rn_l = t; 400 else 401 p->rn_r = t; 402 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 403 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 404 t->rn_r = x; 405 } else { 406 t->rn_r = tt; t->rn_l = x; 407 } 408 #ifdef RN_DEBUG 409 if (rn_debug) 410 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 411 #endif 412 } 413 return (tt); 414 } 415 416 struct radix_node * 417 rn_addmask(n_arg, search, skip) 418 int search, skip; 419 void *n_arg; 420 { 421 caddr_t netmask = (caddr_t)n_arg; 422 register struct radix_node *x; 423 register caddr_t cp, cplim; 424 register int b = 0, mlen, j; 425 int maskduplicated, m0, isnormal; 426 struct radix_node *saved_x; 427 static int last_zeroed = 0; 428 429 if ((mlen = *(u_char *)netmask) > max_keylen) 430 mlen = max_keylen; 431 if (skip == 0) 432 skip = 1; 433 if (mlen <= skip) 434 return (mask_rnhead->rnh_nodes); 435 if (skip > 1) 436 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 437 if ((m0 = mlen) > skip) 438 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 439 /* 440 * Trim trailing zeroes. 441 */ 442 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 443 cp--; 444 mlen = cp - addmask_key; 445 if (mlen <= skip) { 446 if (m0 >= last_zeroed) 447 last_zeroed = mlen; 448 return (mask_rnhead->rnh_nodes); 449 } 450 if (m0 < last_zeroed) 451 Bzero(addmask_key + m0, last_zeroed - m0); 452 *addmask_key = last_zeroed = mlen; 453 x = rn_search(addmask_key, rn_masktop); 454 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 455 x = 0; 456 if (x || search) 457 return (x); 458 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 459 if ((saved_x = x) == 0) 460 return (0); 461 Bzero(x, max_keylen + 2 * sizeof (*x)); 462 netmask = cp = (caddr_t)(x + 2); 463 Bcopy(addmask_key, cp, mlen); 464 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 465 if (maskduplicated) { 466 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 467 Free(saved_x); 468 return (x); 469 } 470 /* 471 * Calculate index of mask, and check for normalcy. 472 */ 473 cplim = netmask + mlen; isnormal = 1; 474 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 475 cp++; 476 if (cp != cplim) { 477 for (j = 0x80; (j & *cp) != 0; j >>= 1) 478 b++; 479 if (*cp != normal_chars[b] || cp != (cplim - 1)) 480 isnormal = 0; 481 } 482 b += (cp - netmask) << 3; 483 x->rn_b = -1 - b; 484 if (isnormal) 485 x->rn_flags |= RNF_NORMAL; 486 return (x); 487 } 488 489 static int /* XXX: arbitrary ordering for non-contiguous masks */ 490 rn_lexobetter(m_arg, n_arg) 491 void *m_arg, *n_arg; 492 { 493 register u_char *mp = m_arg, *np = n_arg, *lim; 494 495 if (*mp > *np) 496 return 1; /* not really, but need to check longer one first */ 497 if (*mp == *np) 498 for (lim = mp + *mp; mp < lim;) 499 if (*mp++ > *np++) 500 return 1; 501 return 0; 502 } 503 504 static struct radix_mask * 505 rn_new_radix_mask(tt, next) 506 register struct radix_node *tt; 507 register struct radix_mask *next; 508 { 509 register struct radix_mask *m; 510 511 MKGet(m); 512 if (m == 0) { 513 log(LOG_ERR, "Mask for route not entered\n"); 514 return (0); 515 } 516 Bzero(m, sizeof *m); 517 m->rm_b = tt->rn_b; 518 m->rm_flags = tt->rn_flags; 519 if (tt->rn_flags & RNF_NORMAL) 520 m->rm_leaf = tt; 521 else 522 m->rm_mask = tt->rn_mask; 523 m->rm_mklist = next; 524 tt->rn_mklist = m; 525 return m; 526 } 527 528 struct radix_node * 529 rn_addroute(v_arg, n_arg, head, treenodes) 530 void *v_arg, *n_arg; 531 struct radix_node_head *head; 532 struct radix_node treenodes[2]; 533 { 534 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 535 register struct radix_node *t, *x = 0, *tt; 536 struct radix_node *saved_tt, *top = head->rnh_treetop; 537 short b = 0, b_leaf = 0; 538 int keyduplicated; 539 caddr_t mmask; 540 struct radix_mask *m, **mp; 541 542 /* 543 * In dealing with non-contiguous masks, there may be 544 * many different routes which have the same mask. 545 * We will find it useful to have a unique pointer to 546 * the mask to speed avoiding duplicate references at 547 * nodes and possibly save time in calculating indices. 548 */ 549 if (netmask) { 550 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 551 return (0); 552 b_leaf = x->rn_b; 553 b = -1 - x->rn_b; 554 netmask = x->rn_key; 555 } 556 /* 557 * Deal with duplicated keys: attach node to previous instance 558 */ 559 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 560 if (keyduplicated) { 561 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 562 if (tt->rn_mask == netmask) 563 return (0); 564 if (netmask == 0 || 565 (tt->rn_mask && 566 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 567 rn_refines(netmask, tt->rn_mask) || 568 rn_lexobetter(netmask, tt->rn_mask)))) 569 break; 570 } 571 /* 572 * If the mask is not duplicated, we wouldn't 573 * find it among possible duplicate key entries 574 * anyway, so the above test doesn't hurt. 575 * 576 * We sort the masks for a duplicated key the same way as 577 * in a masklist -- most specific to least specific. 578 * This may require the unfortunate nuisance of relocating 579 * the head of the list. 580 */ 581 if (tt == saved_tt) { 582 struct radix_node *xx = x; 583 /* link in at head of list */ 584 (tt = treenodes)->rn_dupedkey = t; 585 tt->rn_flags = t->rn_flags; 586 tt->rn_p = x = t->rn_p; 587 t->rn_p = tt; /* parent */ 588 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 589 saved_tt = tt; x = xx; 590 } else { 591 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 592 t->rn_dupedkey = tt; 593 tt->rn_p = t; /* parent */ 594 if (tt->rn_dupedkey) /* parent */ 595 tt->rn_dupedkey->rn_p = tt; /* parent */ 596 } 597 #ifdef RN_DEBUG 598 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 599 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 600 #endif 601 tt->rn_key = (caddr_t) v; 602 tt->rn_b = -1; 603 tt->rn_flags = RNF_ACTIVE; 604 } 605 /* 606 * Put mask in tree. 607 */ 608 if (netmask) { 609 tt->rn_mask = netmask; 610 tt->rn_b = x->rn_b; 611 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 612 } 613 t = saved_tt->rn_p; 614 if (keyduplicated) 615 goto on2; 616 b_leaf = -1 - t->rn_b; 617 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 618 /* Promote general routes from below */ 619 if (x->rn_b < 0) { 620 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 621 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 622 *mp = m = rn_new_radix_mask(x, 0); 623 if (m) 624 mp = &m->rm_mklist; 625 } 626 } else if (x->rn_mklist) { 627 /* 628 * Skip over masks whose index is > that of new node 629 */ 630 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 631 if (m->rm_b >= b_leaf) 632 break; 633 t->rn_mklist = m; *mp = 0; 634 } 635 on2: 636 /* Add new route to highest possible ancestor's list */ 637 if ((netmask == 0) || (b > t->rn_b )) 638 return tt; /* can't lift at all */ 639 b_leaf = tt->rn_b; 640 do { 641 x = t; 642 t = t->rn_p; 643 } while (b <= t->rn_b && x != top); 644 /* 645 * Search through routes associated with node to 646 * insert new route according to index. 647 * Need same criteria as when sorting dupedkeys to avoid 648 * double loop on deletion. 649 */ 650 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 651 if (m->rm_b < b_leaf) 652 continue; 653 if (m->rm_b > b_leaf) 654 break; 655 if (m->rm_flags & RNF_NORMAL) { 656 mmask = m->rm_leaf->rn_mask; 657 if (tt->rn_flags & RNF_NORMAL) { 658 log(LOG_ERR, 659 "Non-unique normal route, mask not entered"); 660 return tt; 661 } 662 } else 663 mmask = m->rm_mask; 664 if (mmask == netmask) { 665 m->rm_refs++; 666 tt->rn_mklist = m; 667 return tt; 668 } 669 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 670 break; 671 } 672 *mp = rn_new_radix_mask(tt, *mp); 673 return tt; 674 } 675 676 static struct radix_node * 677 rn_delete(v_arg, netmask_arg, head) 678 void *v_arg, *netmask_arg; 679 struct radix_node_head *head; 680 { 681 register struct radix_node *t, *p, *x, *tt; 682 struct radix_mask *m, *saved_m, **mp; 683 struct radix_node *dupedkey, *saved_tt, *top; 684 caddr_t v, netmask; 685 int b, head_off, vlen; 686 687 v = v_arg; 688 netmask = netmask_arg; 689 x = head->rnh_treetop; 690 tt = rn_search(v, x); 691 head_off = x->rn_off; 692 vlen = *(u_char *)v; 693 saved_tt = tt; 694 top = x; 695 if (tt == 0 || 696 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 697 return (0); 698 /* 699 * Delete our route from mask lists. 700 */ 701 if (netmask) { 702 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 703 return (0); 704 netmask = x->rn_key; 705 while (tt->rn_mask != netmask) 706 if ((tt = tt->rn_dupedkey) == 0) 707 return (0); 708 } 709 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 710 goto on1; 711 if (tt->rn_flags & RNF_NORMAL) { 712 if (m->rm_leaf != tt || m->rm_refs > 0) { 713 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 714 return 0; /* dangling ref could cause disaster */ 715 } 716 } else { 717 if (m->rm_mask != tt->rn_mask) { 718 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 719 goto on1; 720 } 721 if (--m->rm_refs >= 0) 722 goto on1; 723 } 724 b = -1 - tt->rn_b; 725 t = saved_tt->rn_p; 726 if (b > t->rn_b) 727 goto on1; /* Wasn't lifted at all */ 728 do { 729 x = t; 730 t = t->rn_p; 731 } while (b <= t->rn_b && x != top); 732 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 733 if (m == saved_m) { 734 *mp = m->rm_mklist; 735 MKFree(m); 736 break; 737 } 738 if (m == 0) { 739 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 740 if (tt->rn_flags & RNF_NORMAL) 741 return (0); /* Dangling ref to us */ 742 } 743 on1: 744 /* 745 * Eliminate us from tree 746 */ 747 if (tt->rn_flags & RNF_ROOT) 748 return (0); 749 #ifdef RN_DEBUG 750 /* Get us out of the creation list */ 751 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 752 if (t) t->rn_ybro = tt->rn_ybro; 753 #endif 754 t = tt->rn_p; 755 dupedkey = saved_tt->rn_dupedkey; 756 if (dupedkey) { 757 /* 758 * at this point, tt is the deletion target and saved_tt 759 * is the head of the dupekey chain 760 */ 761 if (tt == saved_tt) { 762 /* remove from head of chain */ 763 x = dupedkey; x->rn_p = t; 764 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 765 } else { 766 /* find node in front of tt on the chain */ 767 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 768 p = p->rn_dupedkey; 769 if (p) { 770 p->rn_dupedkey = tt->rn_dupedkey; 771 if (tt->rn_dupedkey) /* parent */ 772 tt->rn_dupedkey->rn_p = p; /* parent */ 773 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 774 } 775 t = tt + 1; 776 if (t->rn_flags & RNF_ACTIVE) { 777 #ifndef RN_DEBUG 778 *++x = *t; p = t->rn_p; 779 #else 780 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 781 #endif 782 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 783 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 784 } 785 goto out; 786 } 787 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 788 p = t->rn_p; 789 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 790 x->rn_p = p; 791 /* 792 * Demote routes attached to us. 793 */ 794 if (t->rn_mklist) { 795 if (x->rn_b >= 0) { 796 for (mp = &x->rn_mklist; (m = *mp);) 797 mp = &m->rm_mklist; 798 *mp = t->rn_mklist; 799 } else { 800 /* If there are any key,mask pairs in a sibling 801 duped-key chain, some subset will appear sorted 802 in the same order attached to our mklist */ 803 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 804 if (m == x->rn_mklist) { 805 struct radix_mask *mm = m->rm_mklist; 806 x->rn_mklist = 0; 807 if (--(m->rm_refs) < 0) 808 MKFree(m); 809 m = mm; 810 } 811 if (m) 812 log(LOG_ERR, "%s %p at %x\n", 813 "rn_delete: Orphaned Mask", m, x); 814 } 815 } 816 /* 817 * We may be holding an active internal node in the tree. 818 */ 819 x = tt + 1; 820 if (t != x) { 821 #ifndef RN_DEBUG 822 *t = *x; 823 #else 824 b = t->rn_info; *t = *x; t->rn_info = b; 825 #endif 826 t->rn_l->rn_p = t; t->rn_r->rn_p = t; 827 p = x->rn_p; 828 if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; 829 } 830 out: 831 tt->rn_flags &= ~RNF_ACTIVE; 832 tt[1].rn_flags &= ~RNF_ACTIVE; 833 return (tt); 834 } 835 836 /* 837 * This is the same as rn_walktree() except for the parameters and the 838 * exit. 839 */ 840 static int 841 rn_walktree_from(h, a, m, f, w) 842 struct radix_node_head *h; 843 void *a, *m; 844 walktree_f_t *f; 845 void *w; 846 { 847 int error; 848 struct radix_node *base, *next; 849 u_char *xa = (u_char *)a; 850 u_char *xm = (u_char *)m; 851 register struct radix_node *rn, *last = 0 /* shut up gcc */; 852 int stopping = 0; 853 int lastb; 854 855 /* 856 * rn_search_m is sort-of-open-coded here. 857 */ 858 /* printf("about to search\n"); */ 859 for (rn = h->rnh_treetop; rn->rn_b >= 0; ) { 860 last = rn; 861 /* printf("rn_b %d, rn_bmask %x, xm[rn_off] %x\n", 862 rn->rn_b, rn->rn_bmask, xm[rn->rn_off]); */ 863 if (!(rn->rn_bmask & xm[rn->rn_off])) { 864 break; 865 } 866 if (rn->rn_bmask & xa[rn->rn_off]) { 867 rn = rn->rn_r; 868 } else { 869 rn = rn->rn_l; 870 } 871 } 872 /* printf("done searching\n"); */ 873 874 /* 875 * Two cases: either we stepped off the end of our mask, 876 * in which case last == rn, or we reached a leaf, in which 877 * case we want to start from the last node we looked at. 878 * Either way, last is the node we want to start from. 879 */ 880 rn = last; 881 lastb = rn->rn_b; 882 883 /* printf("rn %p, lastb %d\n", rn, lastb);*/ 884 885 /* 886 * This gets complicated because we may delete the node 887 * while applying the function f to it, so we need to calculate 888 * the successor node in advance. 889 */ 890 while (rn->rn_b >= 0) 891 rn = rn->rn_l; 892 893 while (!stopping) { 894 /* printf("node %p (%d)\n", rn, rn->rn_b); */ 895 base = rn; 896 /* If at right child go back up, otherwise, go right */ 897 while (rn->rn_p->rn_r == rn && !(rn->rn_flags & RNF_ROOT)) { 898 rn = rn->rn_p; 899 900 /* if went up beyond last, stop */ 901 if (rn->rn_b < lastb) { 902 stopping = 1; 903 /* printf("up too far\n"); */ 904 } 905 } 906 907 /* Find the next *leaf* since next node might vanish, too */ 908 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 909 rn = rn->rn_l; 910 next = rn; 911 /* Process leaves */ 912 while ((rn = base) != 0) { 913 base = rn->rn_dupedkey; 914 /* printf("leaf %p\n", rn); */ 915 if (!(rn->rn_flags & RNF_ROOT) 916 && (error = (*f)(rn, w))) 917 return (error); 918 } 919 rn = next; 920 921 if (rn->rn_flags & RNF_ROOT) { 922 /* printf("root, stopping"); */ 923 stopping = 1; 924 } 925 926 } 927 return 0; 928 } 929 930 static int 931 rn_walktree(h, f, w) 932 struct radix_node_head *h; 933 walktree_f_t *f; 934 void *w; 935 { 936 int error; 937 struct radix_node *base, *next; 938 register struct radix_node *rn = h->rnh_treetop; 939 /* 940 * This gets complicated because we may delete the node 941 * while applying the function f to it, so we need to calculate 942 * the successor node in advance. 943 */ 944 /* First time through node, go left */ 945 while (rn->rn_b >= 0) 946 rn = rn->rn_l; 947 for (;;) { 948 base = rn; 949 /* If at right child go back up, otherwise, go right */ 950 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 951 rn = rn->rn_p; 952 /* Find the next *leaf* since next node might vanish, too */ 953 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 954 rn = rn->rn_l; 955 next = rn; 956 /* Process leaves */ 957 while ((rn = base)) { 958 base = rn->rn_dupedkey; 959 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 960 return (error); 961 } 962 rn = next; 963 if (rn->rn_flags & RNF_ROOT) 964 return (0); 965 } 966 /* NOTREACHED */ 967 } 968 969 int 970 rn_inithead(head, off) 971 void **head; 972 int off; 973 { 974 register struct radix_node_head *rnh; 975 register struct radix_node *t, *tt, *ttt; 976 if (*head) 977 return (1); 978 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 979 if (rnh == 0) 980 return (0); 981 Bzero(rnh, sizeof (*rnh)); 982 *head = rnh; 983 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 984 ttt = rnh->rnh_nodes + 2; 985 t->rn_r = ttt; 986 t->rn_p = t; 987 tt = t->rn_l; 988 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 989 tt->rn_b = -1 - off; 990 *ttt = *tt; 991 ttt->rn_key = rn_ones; 992 rnh->rnh_addaddr = rn_addroute; 993 rnh->rnh_deladdr = rn_delete; 994 rnh->rnh_matchaddr = rn_match; 995 rnh->rnh_lookup = rn_lookup; 996 rnh->rnh_walktree = rn_walktree; 997 rnh->rnh_walktree_from = rn_walktree_from; 998 rnh->rnh_treetop = t; 999 return (1); 1000 } 1001 1002 void 1003 rn_init() 1004 { 1005 char *cp, *cplim; 1006 #ifdef KERNEL 1007 struct domain *dom; 1008 1009 for (dom = domains; dom; dom = dom->dom_next) 1010 if (dom->dom_maxrtkey > max_keylen) 1011 max_keylen = dom->dom_maxrtkey; 1012 #endif 1013 if (max_keylen == 0) { 1014 log(LOG_ERR, 1015 "rn_init: radix functions require max_keylen be set\n"); 1016 return; 1017 } 1018 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1019 if (rn_zeros == NULL) 1020 panic("rn_init"); 1021 Bzero(rn_zeros, 3 * max_keylen); 1022 rn_ones = cp = rn_zeros + max_keylen; 1023 addmask_key = cplim = rn_ones + max_keylen; 1024 while (cp < cplim) 1025 *cp++ = -1; 1026 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 1027 panic("rn_init 2"); 1028 }
Cache object: 1e026c463283430970e1df1af30b4ec2
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