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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) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 74 75 static int rn_lexobetter __P((void *m_arg, void *n_arg)); 76 static struct radix_mask * 77 rn_new_radix_mask __P((struct radix_node *tt, 78 struct radix_mask *next)); 79 static int rn_satsifies_leaf __P((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_b 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_b - 1. 87 * (We say the index of n is rn_b.) 88 * 89 * There is at least one descendant which has a one bit at position rn_b, 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_b, 100 * and m is a normal mask, then the route applies to every descendant of n. 101 * If the index(m) < rn_b, 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_b >= 0;) { 125 if (x->rn_bmask & v[x->rn_off]) 126 x = x->rn_r; 127 else 128 x = x->rn_l; 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_b >= 0;) { 142 if ((x->rn_bmask & m[x->rn_off]) && 143 (x->rn_bmask & v[x->rn_off])) 144 x = x->rn_r; 145 else 146 x = x->rn_l; 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 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 188 return (0); 189 netmask = x->rn_key; 190 } 191 x = rn_match(v_arg, head); 192 if (x && netmask) { 193 while (x && x->rn_mask != netmask) 194 x = x->rn_dupedkey; 195 } 196 return x; 197 } 198 199 static int 200 rn_satsifies_leaf(trial, leaf, skip) 201 char *trial; 202 register struct radix_node *leaf; 203 int skip; 204 { 205 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 206 char *cplim; 207 int length = min(*(u_char *)cp, *(u_char *)cp2); 208 209 if (cp3 == 0) 210 cp3 = rn_ones; 211 else 212 length = min(length, *(u_char *)cp3); 213 cplim = cp + length; cp3 += skip; cp2 += skip; 214 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 215 if ((*cp ^ *cp2) & *cp3) 216 return 0; 217 return 1; 218 } 219 220 struct radix_node * 221 rn_match(v_arg, head) 222 void *v_arg; 223 struct radix_node_head *head; 224 { 225 caddr_t v = v_arg; 226 register struct radix_node *t = head->rnh_treetop, *x; 227 register caddr_t cp = v, cp2; 228 caddr_t cplim; 229 struct radix_node *saved_t, *top = t; 230 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 231 register int test, b, rn_b; 232 233 /* 234 * Open code rn_search(v, top) to avoid overhead of extra 235 * subroutine call. 236 */ 237 for (; t->rn_b >= 0; ) { 238 if (t->rn_bmask & cp[t->rn_off]) 239 t = t->rn_r; 240 else 241 t = t->rn_l; 242 } 243 /* 244 * See if we match exactly as a host destination 245 * or at least learn how many bits match, for normal mask finesse. 246 * 247 * It doesn't hurt us to limit how many bytes to check 248 * to the length of the mask, since if it matches we had a genuine 249 * match and the leaf we have is the most specific one anyway; 250 * if it didn't match with a shorter length it would fail 251 * with a long one. This wins big for class B&C netmasks which 252 * are probably the most common case... 253 */ 254 if (t->rn_mask) 255 vlen = *(u_char *)t->rn_mask; 256 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 257 for (; cp < cplim; cp++, cp2++) 258 if (*cp != *cp2) 259 goto on1; 260 /* 261 * This extra grot is in case we are explicitly asked 262 * to look up the default. Ugh! 263 * 264 * Never return the root node itself, it seems to cause a 265 * lot of confusion. 266 */ 267 if (t->rn_flags & RNF_ROOT) 268 t = t->rn_dupedkey; 269 return t; 270 on1: 271 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 272 for (b = 7; (test >>= 1) > 0;) 273 b--; 274 matched_off = cp - v; 275 b += matched_off << 3; 276 rn_b = -1 - b; 277 /* 278 * If there is a host route in a duped-key chain, it will be first. 279 */ 280 if ((saved_t = t)->rn_mask == 0) 281 t = t->rn_dupedkey; 282 for (; t; t = t->rn_dupedkey) 283 /* 284 * Even if we don't match exactly as a host, 285 * we may match if the leaf we wound up at is 286 * a route to a net. 287 */ 288 if (t->rn_flags & RNF_NORMAL) { 289 if (rn_b <= t->rn_b) 290 return t; 291 } else if (rn_satsifies_leaf(v, t, matched_off)) 292 return t; 293 t = saved_t; 294 /* start searching up the tree */ 295 do { 296 register struct radix_mask *m; 297 t = t->rn_p; 298 m = t->rn_mklist; 299 if (m) { 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 do { 307 if (m->rm_flags & RNF_NORMAL) { 308 if (rn_b <= m->rm_b) 309 return (m->rm_leaf); 310 } else { 311 off = min(t->rn_off, 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_satsifies_leaf(v, x, off)) 316 return x; 317 } 318 m = m->rm_mklist; 319 } while (m); 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_b = b; t->rn_bmask = 0x80 >> (b & 7); 340 t->rn_l = tt; t->rn_off = b >> 3; 341 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 342 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 343 #ifdef RN_DEBUG 344 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 345 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 346 #endif 347 return t; 348 } 349 350 static struct radix_node * 351 rn_insert(v_arg, head, dupentry, nodes) 352 void *v_arg; 353 struct radix_node_head *head; 354 int *dupentry; 355 struct radix_node nodes[2]; 356 { 357 caddr_t v = v_arg; 358 struct radix_node *top = head->rnh_treetop; 359 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 360 register struct radix_node *t = rn_search(v_arg, top); 361 register caddr_t cp = v + head_off; 362 register int b; 363 struct radix_node *tt; 364 /* 365 * Find first bit at which v and t->rn_key differ 366 */ 367 { 368 register caddr_t cp2 = t->rn_key + head_off; 369 register int cmp_res; 370 caddr_t cplim = v + vlen; 371 372 while (cp < cplim) 373 if (*cp2++ != *cp++) 374 goto on1; 375 *dupentry = 1; 376 return t; 377 on1: 378 *dupentry = 0; 379 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 380 for (b = (cp - v) << 3; cmp_res; b--) 381 cmp_res >>= 1; 382 } 383 { 384 register struct radix_node *p, *x = top; 385 cp = v; 386 do { 387 p = x; 388 if (cp[x->rn_off] & x->rn_bmask) 389 x = x->rn_r; 390 else x = x->rn_l; 391 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 392 #ifdef RN_DEBUG 393 if (rn_debug) 394 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 395 #endif 396 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 397 if ((cp[p->rn_off] & p->rn_bmask) == 0) 398 p->rn_l = t; 399 else 400 p->rn_r = t; 401 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 402 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 403 t->rn_r = x; 404 } else { 405 t->rn_r = tt; t->rn_l = x; 406 } 407 #ifdef RN_DEBUG 408 if (rn_debug) 409 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 410 #endif 411 } 412 return (tt); 413 } 414 415 struct radix_node * 416 rn_addmask(n_arg, search, skip) 417 int search, skip; 418 void *n_arg; 419 { 420 caddr_t netmask = (caddr_t)n_arg; 421 register struct radix_node *x; 422 register caddr_t cp, cplim; 423 register int b = 0, mlen, j; 424 int maskduplicated, m0, isnormal; 425 struct radix_node *saved_x; 426 static int last_zeroed = 0; 427 428 if ((mlen = *(u_char *)netmask) > max_keylen) 429 mlen = max_keylen; 430 if (skip == 0) 431 skip = 1; 432 if (mlen <= skip) 433 return (mask_rnhead->rnh_nodes); 434 if (skip > 1) 435 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 436 if ((m0 = mlen) > skip) 437 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 438 /* 439 * Trim trailing zeroes. 440 */ 441 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 442 cp--; 443 mlen = cp - addmask_key; 444 if (mlen <= skip) { 445 if (m0 >= last_zeroed) 446 last_zeroed = mlen; 447 return (mask_rnhead->rnh_nodes); 448 } 449 if (m0 < last_zeroed) 450 Bzero(addmask_key + m0, last_zeroed - m0); 451 *addmask_key = last_zeroed = mlen; 452 x = rn_search(addmask_key, rn_masktop); 453 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 454 x = 0; 455 if (x || search) 456 return (x); 457 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 458 if ((saved_x = x) == 0) 459 return (0); 460 Bzero(x, max_keylen + 2 * sizeof (*x)); 461 netmask = cp = (caddr_t)(x + 2); 462 Bcopy(addmask_key, cp, mlen); 463 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 464 if (maskduplicated) { 465 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 466 Free(saved_x); 467 return (x); 468 } 469 /* 470 * Calculate index of mask, and check for normalcy. 471 */ 472 cplim = netmask + mlen; isnormal = 1; 473 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 474 cp++; 475 if (cp != cplim) { 476 for (j = 0x80; (j & *cp) != 0; j >>= 1) 477 b++; 478 if (*cp != normal_chars[b] || cp != (cplim - 1)) 479 isnormal = 0; 480 } 481 b += (cp - netmask) << 3; 482 x->rn_b = -1 - b; 483 if (isnormal) 484 x->rn_flags |= RNF_NORMAL; 485 return (x); 486 } 487 488 static int /* XXX: arbitrary ordering for non-contiguous masks */ 489 rn_lexobetter(m_arg, n_arg) 490 void *m_arg, *n_arg; 491 { 492 register u_char *mp = m_arg, *np = n_arg, *lim; 493 494 if (*mp > *np) 495 return 1; /* not really, but need to check longer one first */ 496 if (*mp == *np) 497 for (lim = mp + *mp; mp < lim;) 498 if (*mp++ > *np++) 499 return 1; 500 return 0; 501 } 502 503 static struct radix_mask * 504 rn_new_radix_mask(tt, next) 505 register struct radix_node *tt; 506 register struct radix_mask *next; 507 { 508 register struct radix_mask *m; 509 510 MKGet(m); 511 if (m == 0) { 512 log(LOG_ERR, "Mask for route not entered\n"); 513 return (0); 514 } 515 Bzero(m, sizeof *m); 516 m->rm_b = tt->rn_b; 517 m->rm_flags = tt->rn_flags; 518 if (tt->rn_flags & RNF_NORMAL) 519 m->rm_leaf = tt; 520 else 521 m->rm_mask = tt->rn_mask; 522 m->rm_mklist = next; 523 tt->rn_mklist = m; 524 return m; 525 } 526 527 struct radix_node * 528 rn_addroute(v_arg, n_arg, head, treenodes) 529 void *v_arg, *n_arg; 530 struct radix_node_head *head; 531 struct radix_node treenodes[2]; 532 { 533 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 534 register struct radix_node *t, *x = 0, *tt; 535 struct radix_node *saved_tt, *top = head->rnh_treetop; 536 short b = 0, b_leaf = 0; 537 int keyduplicated; 538 caddr_t mmask; 539 struct radix_mask *m, **mp; 540 541 /* 542 * In dealing with non-contiguous masks, there may be 543 * many different routes which have the same mask. 544 * We will find it useful to have a unique pointer to 545 * the mask to speed avoiding duplicate references at 546 * nodes and possibly save time in calculating indices. 547 */ 548 if (netmask) { 549 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 550 return (0); 551 b_leaf = x->rn_b; 552 b = -1 - x->rn_b; 553 netmask = x->rn_key; 554 } 555 /* 556 * Deal with duplicated keys: attach node to previous instance 557 */ 558 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 559 if (keyduplicated) { 560 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 561 if (tt->rn_mask == netmask) 562 return (0); 563 if (netmask == 0 || 564 (tt->rn_mask && 565 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 566 rn_refines(netmask, tt->rn_mask) || 567 rn_lexobetter(netmask, tt->rn_mask)))) 568 break; 569 } 570 /* 571 * If the mask is not duplicated, we wouldn't 572 * find it among possible duplicate key entries 573 * anyway, so the above test doesn't hurt. 574 * 575 * We sort the masks for a duplicated key the same way as 576 * in a masklist -- most specific to least specific. 577 * This may require the unfortunate nuisance of relocating 578 * the head of the list. 579 */ 580 if (tt == saved_tt) { 581 struct radix_node *xx = x; 582 /* link in at head of list */ 583 (tt = treenodes)->rn_dupedkey = t; 584 tt->rn_flags = t->rn_flags; 585 tt->rn_p = x = t->rn_p; 586 t->rn_p = tt; /* parent */ 587 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 588 saved_tt = tt; x = xx; 589 } else { 590 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 591 t->rn_dupedkey = tt; 592 tt->rn_p = t; /* parent */ 593 if (tt->rn_dupedkey) /* parent */ 594 tt->rn_dupedkey->rn_p = tt; /* parent */ 595 } 596 #ifdef RN_DEBUG 597 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 598 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 599 #endif 600 tt->rn_key = (caddr_t) v; 601 tt->rn_b = -1; 602 tt->rn_flags = RNF_ACTIVE; 603 } 604 /* 605 * Put mask in tree. 606 */ 607 if (netmask) { 608 tt->rn_mask = netmask; 609 tt->rn_b = x->rn_b; 610 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 611 } 612 t = saved_tt->rn_p; 613 if (keyduplicated) 614 goto on2; 615 b_leaf = -1 - t->rn_b; 616 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 617 /* Promote general routes from below */ 618 if (x->rn_b < 0) { 619 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 620 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 621 *mp = m = rn_new_radix_mask(x, 0); 622 if (m) 623 mp = &m->rm_mklist; 624 } 625 } else if (x->rn_mklist) { 626 /* 627 * Skip over masks whose index is > that of new node 628 */ 629 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 630 if (m->rm_b >= b_leaf) 631 break; 632 t->rn_mklist = m; *mp = 0; 633 } 634 on2: 635 /* Add new route to highest possible ancestor's list */ 636 if ((netmask == 0) || (b > t->rn_b )) 637 return tt; /* can't lift at all */ 638 b_leaf = tt->rn_b; 639 do { 640 x = t; 641 t = t->rn_p; 642 } while (b <= t->rn_b && x != top); 643 /* 644 * Search through routes associated with node to 645 * insert new route according to index. 646 * Need same criteria as when sorting dupedkeys to avoid 647 * double loop on deletion. 648 */ 649 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 650 if (m->rm_b < b_leaf) 651 continue; 652 if (m->rm_b > b_leaf) 653 break; 654 if (m->rm_flags & RNF_NORMAL) { 655 mmask = m->rm_leaf->rn_mask; 656 if (tt->rn_flags & RNF_NORMAL) { 657 log(LOG_ERR, 658 "Non-unique normal route, mask not entered"); 659 return tt; 660 } 661 } else 662 mmask = m->rm_mask; 663 if (mmask == netmask) { 664 m->rm_refs++; 665 tt->rn_mklist = m; 666 return tt; 667 } 668 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 669 break; 670 } 671 *mp = rn_new_radix_mask(tt, *mp); 672 return tt; 673 } 674 675 struct radix_node * 676 rn_delete(v_arg, netmask_arg, head) 677 void *v_arg, *netmask_arg; 678 struct radix_node_head *head; 679 { 680 register struct radix_node *t, *p, *x, *tt; 681 struct radix_mask *m, *saved_m, **mp; 682 struct radix_node *dupedkey, *saved_tt, *top; 683 caddr_t v, netmask; 684 int b, head_off, vlen; 685 686 v = v_arg; 687 netmask = netmask_arg; 688 x = head->rnh_treetop; 689 tt = rn_search(v, x); 690 head_off = x->rn_off; 691 vlen = *(u_char *)v; 692 saved_tt = tt; 693 top = x; 694 if (tt == 0 || 695 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 696 return (0); 697 /* 698 * Delete our route from mask lists. 699 */ 700 if (netmask) { 701 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 702 return (0); 703 netmask = x->rn_key; 704 while (tt->rn_mask != netmask) 705 if ((tt = tt->rn_dupedkey) == 0) 706 return (0); 707 } 708 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 709 goto on1; 710 if (tt->rn_flags & RNF_NORMAL) { 711 if (m->rm_leaf != tt || m->rm_refs > 0) { 712 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 713 return 0; /* dangling ref could cause disaster */ 714 } 715 } else { 716 if (m->rm_mask != tt->rn_mask) { 717 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 718 goto on1; 719 } 720 if (--m->rm_refs >= 0) 721 goto on1; 722 } 723 b = -1 - tt->rn_b; 724 t = saved_tt->rn_p; 725 if (b > t->rn_b) 726 goto on1; /* Wasn't lifted at all */ 727 do { 728 x = t; 729 t = t->rn_p; 730 } while (b <= t->rn_b && x != top); 731 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 732 if (m == saved_m) { 733 *mp = m->rm_mklist; 734 MKFree(m); 735 break; 736 } 737 if (m == 0) { 738 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 739 if (tt->rn_flags & RNF_NORMAL) 740 return (0); /* Dangling ref to us */ 741 } 742 on1: 743 /* 744 * Eliminate us from tree 745 */ 746 if (tt->rn_flags & RNF_ROOT) 747 return (0); 748 #ifdef RN_DEBUG 749 /* Get us out of the creation list */ 750 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 751 if (t) t->rn_ybro = tt->rn_ybro; 752 #endif 753 t = tt->rn_p; 754 dupedkey = saved_tt->rn_dupedkey; 755 if (dupedkey) { 756 /* 757 * at this point, tt is the deletion target and saved_tt 758 * is the head of the dupekey chain 759 */ 760 if (tt == saved_tt) { 761 /* remove from head of chain */ 762 x = dupedkey; x->rn_p = t; 763 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 764 } else { 765 /* find node in front of tt on the chain */ 766 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 767 p = p->rn_dupedkey; 768 if (p) { 769 p->rn_dupedkey = tt->rn_dupedkey; 770 if (tt->rn_dupedkey) /* parent */ 771 tt->rn_dupedkey->rn_p = p; /* parent */ 772 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 773 } 774 t = tt + 1; 775 if (t->rn_flags & RNF_ACTIVE) { 776 #ifndef RN_DEBUG 777 *++x = *t; p = t->rn_p; 778 #else 779 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 780 #endif 781 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 782 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 783 } 784 goto out; 785 } 786 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 787 p = t->rn_p; 788 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 789 x->rn_p = p; 790 /* 791 * Demote routes attached to us. 792 */ 793 if (t->rn_mklist) { 794 if (x->rn_b >= 0) { 795 for (mp = &x->rn_mklist; (m = *mp);) 796 mp = &m->rm_mklist; 797 *mp = t->rn_mklist; 798 } else { 799 /* If there are any key,mask pairs in a sibling 800 duped-key chain, some subset will appear sorted 801 in the same order attached to our mklist */ 802 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 803 if (m == x->rn_mklist) { 804 struct radix_mask *mm = m->rm_mklist; 805 x->rn_mklist = 0; 806 if (--(m->rm_refs) < 0) 807 MKFree(m); 808 m = mm; 809 } 810 if (m) 811 log(LOG_ERR, 812 "rn_delete: Orphaned Mask %p at %p\n", 813 (void *)m, (void *)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: db3f6fef41e6b6f8bd6fdd9eb3135efc
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