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 1.20.2.3 2002/04/28 05:40:25 suz Exp $ 35 * $DragonFly: src/sys/net/radix.c,v 1.14 2006/12/22 23:44:54 swildner Exp $ 36 */ 37 38 /* 39 * Routines to build and maintain radix trees for routing lookups. 40 */ 41 #include <sys/param.h> 42 #ifdef _KERNEL 43 #include <sys/systm.h> 44 #include <sys/malloc.h> 45 #include <sys/domain.h> 46 #include <sys/globaldata.h> 47 #include <sys/thread.h> 48 #else 49 #include <stdlib.h> 50 #endif 51 #include <sys/syslog.h> 52 #include <net/radix.h> 53 54 /* 55 * The arguments to the radix functions are really counted byte arrays with 56 * the length in the first byte. struct sockaddr's fit this type structurally. 57 */ 58 #define clen(c) (*(u_char *)(c)) 59 60 static int rn_walktree_from(struct radix_node_head *h, char *a, char *m, 61 walktree_f_t *f, void *w); 62 static int rn_walktree(struct radix_node_head *, walktree_f_t *, void *); 63 64 static struct radix_node 65 *rn_insert(char *, struct radix_node_head *, boolean_t *, 66 struct radix_node [2]), 67 *rn_newpair(char *, int, struct radix_node[2]), 68 *rn_search(const char *, struct radix_node *), 69 *rn_search_m(const char *, struct radix_node *, const char *); 70 71 static struct radix_mask *rn_mkfreelist; 72 static struct radix_node_head *mask_rnheads[MAXCPU]; 73 74 static int max_keylen; 75 static char *rn_zeros, *rn_ones; 76 77 static int rn_lexobetter(char *m, char *n); 78 static struct radix_mask * 79 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *nextmask); 80 static boolean_t 81 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip); 82 83 static __inline struct radix_mask * 84 MKGet(struct radix_mask **l) 85 { 86 struct radix_mask *m; 87 88 if (*l != NULL) { 89 m = *l; 90 *l = m->rm_next; 91 } else { 92 R_Malloc(m, struct radix_mask *, sizeof *m); 93 } 94 return m; 95 } 96 97 static __inline void 98 MKFree(struct radix_mask **l, struct radix_mask *m) 99 { 100 m->rm_next = *l; 101 *l = m; 102 } 103 104 /* 105 * The data structure for the keys is a radix tree with one way 106 * branching removed. The index rn_bit at an internal node n represents a bit 107 * position to be tested. The tree is arranged so that all descendants 108 * of a node n have keys whose bits all agree up to position rn_bit - 1. 109 * (We say the index of n is rn_bit.) 110 * 111 * There is at least one descendant which has a one bit at position rn_bit, 112 * and at least one with a zero there. 113 * 114 * A route is determined by a pair of key and mask. We require that the 115 * bit-wise logical and of the key and mask to be the key. 116 * We define the index of a route to associated with the mask to be 117 * the first bit number in the mask where 0 occurs (with bit number 0 118 * representing the highest order bit). 119 * 120 * We say a mask is normal if every bit is 0, past the index of the mask. 121 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit, 122 * and m is a normal mask, then the route applies to every descendant of n. 123 * If the index(m) < rn_bit, this implies the trailing last few bits of k 124 * before bit b are all 0, (and hence consequently true of every descendant 125 * of n), so the route applies to all descendants of the node as well. 126 * 127 * Similar logic shows that a non-normal mask m such that 128 * index(m) <= index(n) could potentially apply to many children of n. 129 * Thus, for each non-host route, we attach its mask to a list at an internal 130 * node as high in the tree as we can go. 131 * 132 * The present version of the code makes use of normal routes in short- 133 * circuiting an explict mask and compare operation when testing whether 134 * a key satisfies a normal route, and also in remembering the unique leaf 135 * that governs a subtree. 136 */ 137 138 static struct radix_node * 139 rn_search(const char *v, struct radix_node *head) 140 { 141 struct radix_node *x; 142 143 x = head; 144 while (x->rn_bit >= 0) { 145 if (x->rn_bmask & v[x->rn_offset]) 146 x = x->rn_right; 147 else 148 x = x->rn_left; 149 } 150 return (x); 151 } 152 153 static struct radix_node * 154 rn_search_m(const char *v, struct radix_node *head, const char *m) 155 { 156 struct radix_node *x; 157 158 for (x = head; x->rn_bit >= 0;) { 159 if ((x->rn_bmask & m[x->rn_offset]) && 160 (x->rn_bmask & v[x->rn_offset])) 161 x = x->rn_right; 162 else 163 x = x->rn_left; 164 } 165 return x; 166 } 167 168 boolean_t 169 rn_refines(char *m, char *n) 170 { 171 char *lim, *lim2; 172 int longer = clen(n++) - clen(m++); 173 boolean_t masks_are_equal = TRUE; 174 175 lim2 = lim = n + clen(n); 176 if (longer > 0) 177 lim -= longer; 178 while (n < lim) { 179 if (*n & ~(*m)) 180 return FALSE; 181 if (*n++ != *m++) 182 masks_are_equal = FALSE; 183 } 184 while (n < lim2) 185 if (*n++) 186 return FALSE; 187 if (masks_are_equal && (longer < 0)) 188 for (lim2 = m - longer; m < lim2; ) 189 if (*m++) 190 return TRUE; 191 return (!masks_are_equal); 192 } 193 194 struct radix_node * 195 rn_lookup(char *key, char *mask, struct radix_node_head *head) 196 { 197 struct radix_node *x; 198 char *netmask = NULL; 199 200 if (mask != NULL) { 201 x = rn_addmask(mask, TRUE, head->rnh_treetop->rn_offset); 202 if (x == NULL) 203 return (NULL); 204 netmask = x->rn_key; 205 } 206 x = rn_match(key, head); 207 if (x != NULL && netmask != NULL) { 208 while (x != NULL && x->rn_mask != netmask) 209 x = x->rn_dupedkey; 210 } 211 return x; 212 } 213 214 static boolean_t 215 rn_satisfies_leaf(char *trial, struct radix_node *leaf, int skip) 216 { 217 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 218 char *cplim; 219 int length = min(clen(cp), clen(cp2)); 220 221 if (cp3 == NULL) 222 cp3 = rn_ones; 223 else 224 length = min(length, clen(cp3)); 225 cplim = cp + length; 226 cp3 += skip; 227 cp2 += skip; 228 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 229 if ((*cp ^ *cp2) & *cp3) 230 return FALSE; 231 return TRUE; 232 } 233 234 struct radix_node * 235 rn_match(char *key, struct radix_node_head *head) 236 { 237 struct radix_node *t, *x; 238 char *cp = key, *cp2; 239 char *cplim; 240 struct radix_node *saved_t, *top = head->rnh_treetop; 241 int off = top->rn_offset, klen, matched_off; 242 int test, b, rn_bit; 243 244 t = rn_search(key, top); 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 != NULL) 257 klen = clen(t->rn_mask); 258 else 259 klen = clen(key); 260 cp += off; cp2 = t->rn_key + off; cplim = key + klen; 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 * Never return the root node itself, it seems to cause a 269 * lot of confusion. 270 */ 271 if (t->rn_flags & RNF_ROOT) 272 t = t->rn_dupedkey; 273 return t; 274 on1: 275 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 276 for (b = 7; (test >>= 1) > 0;) 277 b--; 278 matched_off = cp - key; 279 b += matched_off << 3; 280 rn_bit = -1 - b; 281 /* 282 * If there is a host route in a duped-key chain, it will be first. 283 */ 284 if ((saved_t = t)->rn_mask == NULL) 285 t = t->rn_dupedkey; 286 for (; t; t = t->rn_dupedkey) { 287 /* 288 * Even if we don't match exactly as a host, 289 * we may match if the leaf we wound up at is 290 * a route to a net. 291 */ 292 if (t->rn_flags & RNF_NORMAL) { 293 if (rn_bit <= t->rn_bit) 294 return t; 295 } else if (rn_satisfies_leaf(key, t, matched_off)) 296 return t; 297 } 298 t = saved_t; 299 /* start searching up the tree */ 300 do { 301 struct radix_mask *m; 302 303 t = t->rn_parent; 304 /* 305 * If non-contiguous masks ever become important 306 * we can restore the masking and open coding of 307 * the search and satisfaction test and put the 308 * calculation of "off" back before the "do". 309 */ 310 m = t->rn_mklist; 311 while (m != NULL) { 312 if (m->rm_flags & RNF_NORMAL) { 313 if (rn_bit <= m->rm_bit) 314 return (m->rm_leaf); 315 } else { 316 off = min(t->rn_offset, matched_off); 317 x = rn_search_m(key, t, m->rm_mask); 318 while (x != NULL && x->rn_mask != m->rm_mask) 319 x = x->rn_dupedkey; 320 if (x && rn_satisfies_leaf(key, x, off)) 321 return x; 322 } 323 m = m->rm_next; 324 } 325 } while (t != top); 326 return NULL; 327 } 328 329 #ifdef RN_DEBUG 330 int rn_nodenum; 331 struct radix_node *rn_clist; 332 int rn_saveinfo; 333 boolean_t rn_debug = TRUE; 334 #endif 335 336 static struct radix_node * 337 rn_newpair(char *key, int indexbit, struct radix_node nodes[2]) 338 { 339 struct radix_node *leaf = &nodes[0], *interior = &nodes[1]; 340 341 interior->rn_bit = indexbit; 342 interior->rn_bmask = 0x80 >> (indexbit & 0x7); 343 interior->rn_offset = indexbit >> 3; 344 interior->rn_left = leaf; 345 interior->rn_mklist = NULL; 346 347 leaf->rn_bit = -1; 348 leaf->rn_key = key; 349 leaf->rn_parent = interior; 350 leaf->rn_flags = interior->rn_flags = RNF_ACTIVE; 351 leaf->rn_mklist = NULL; 352 353 #ifdef RN_DEBUG 354 leaf->rn_info = rn_nodenum++; 355 interior->rn_info = rn_nodenum++; 356 leaf->rn_twin = interior; 357 leaf->rn_ybro = rn_clist; 358 rn_clist = leaf; 359 #endif 360 return interior; 361 } 362 363 static struct radix_node * 364 rn_insert(char *key, struct radix_node_head *head, boolean_t *dupentry, 365 struct radix_node nodes[2]) 366 { 367 struct radix_node *top = head->rnh_treetop; 368 int head_off = top->rn_offset, klen = clen(key); 369 struct radix_node *t = rn_search(key, top); 370 char *cp = key + head_off; 371 int b; 372 struct radix_node *tt; 373 374 /* 375 * Find first bit at which the key and t->rn_key differ 376 */ 377 { 378 char *cp2 = t->rn_key + head_off; 379 int cmp_res; 380 char *cplim = key + klen; 381 382 while (cp < cplim) 383 if (*cp2++ != *cp++) 384 goto on1; 385 *dupentry = TRUE; 386 return t; 387 on1: 388 *dupentry = FALSE; 389 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 390 for (b = (cp - key) << 3; cmp_res; b--) 391 cmp_res >>= 1; 392 } 393 { 394 struct radix_node *p, *x = top; 395 396 cp = key; 397 do { 398 p = x; 399 if (cp[x->rn_offset] & x->rn_bmask) 400 x = x->rn_right; 401 else 402 x = x->rn_left; 403 } while (b > (unsigned) x->rn_bit); 404 /* x->rn_bit < b && x->rn_bit >= 0 */ 405 #ifdef RN_DEBUG 406 if (rn_debug) 407 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 408 #endif 409 t = rn_newpair(key, b, nodes); 410 tt = t->rn_left; 411 if ((cp[p->rn_offset] & p->rn_bmask) == 0) 412 p->rn_left = t; 413 else 414 p->rn_right = t; 415 x->rn_parent = t; 416 t->rn_parent = p; /* frees x, p as temp vars below */ 417 if ((cp[t->rn_offset] & t->rn_bmask) == 0) { 418 t->rn_right = x; 419 } else { 420 t->rn_right = tt; 421 t->rn_left = x; 422 } 423 #ifdef RN_DEBUG 424 if (rn_debug) 425 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 426 #endif 427 } 428 return (tt); 429 } 430 431 struct radix_node * 432 rn_addmask(char *netmask, boolean_t search, int skip) 433 { 434 struct radix_node *x, *saved_x; 435 char *cp, *cplim; 436 int b = 0, mlen, m0, j; 437 boolean_t maskduplicated, isnormal; 438 static int last_zeroed = 0; 439 char *addmask_key; 440 struct radix_node_head *mask_rnh = mask_rnheads[mycpuid]; 441 442 if ((mlen = clen(netmask)) > max_keylen) 443 mlen = max_keylen; 444 if (skip == 0) 445 skip = 1; 446 if (mlen <= skip) 447 return (mask_rnh->rnh_nodes); 448 R_Malloc(addmask_key, char *, max_keylen); 449 if (addmask_key == NULL) 450 return NULL; 451 if (skip > 1) 452 bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 453 if ((m0 = mlen) > skip) 454 bcopy(netmask + skip, addmask_key + skip, mlen - skip); 455 /* 456 * Trim trailing zeroes. 457 */ 458 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 459 cp--; 460 mlen = cp - addmask_key; 461 if (mlen <= skip) { 462 if (m0 >= last_zeroed) 463 last_zeroed = mlen; 464 Free(addmask_key); 465 return (mask_rnh->rnh_nodes); 466 } 467 if (m0 < last_zeroed) 468 bzero(addmask_key + m0, last_zeroed - m0); 469 *addmask_key = last_zeroed = mlen; 470 x = rn_search(addmask_key, mask_rnh->rnh_treetop); 471 if (bcmp(addmask_key, x->rn_key, mlen) != 0) 472 x = NULL; 473 if (x != NULL || search) 474 goto out; 475 R_Malloc(x, struct radix_node *, max_keylen + 2 * (sizeof *x)); 476 if ((saved_x = x) == NULL) 477 goto out; 478 bzero(x, max_keylen + 2 * (sizeof *x)); 479 netmask = cp = (char *)(x + 2); 480 bcopy(addmask_key, cp, mlen); 481 x = rn_insert(cp, mask_rnh, &maskduplicated, x); 482 if (maskduplicated) { 483 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 484 Free(saved_x); 485 goto out; 486 } 487 /* 488 * Calculate index of mask, and check for normalcy. 489 */ 490 isnormal = TRUE; 491 cplim = netmask + mlen; 492 for (cp = netmask + skip; cp < cplim && clen(cp) == 0xff;) 493 cp++; 494 if (cp != cplim) { 495 static const char normal_chars[] = { 496 0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1 497 }; 498 499 for (j = 0x80; (j & *cp) != 0; j >>= 1) 500 b++; 501 if (*cp != normal_chars[b] || cp != (cplim - 1)) 502 isnormal = FALSE; 503 } 504 b += (cp - netmask) << 3; 505 x->rn_bit = -1 - b; 506 if (isnormal) 507 x->rn_flags |= RNF_NORMAL; 508 out: 509 Free(addmask_key); 510 return (x); 511 } 512 513 /* XXX: arbitrary ordering for non-contiguous masks */ 514 static boolean_t 515 rn_lexobetter(char *mp, char *np) 516 { 517 char *lim; 518 519 if ((unsigned) *mp > (unsigned) *np) 520 return TRUE;/* not really, but need to check longer one first */ 521 if (*mp == *np) 522 for (lim = mp + clen(mp); mp < lim;) 523 if (*mp++ > *np++) 524 return TRUE; 525 return FALSE; 526 } 527 528 static struct radix_mask * 529 rn_new_radix_mask(struct radix_node *tt, struct radix_mask *nextmask) 530 { 531 struct radix_mask *m; 532 533 m = MKGet(&rn_mkfreelist); 534 if (m == NULL) { 535 log(LOG_ERR, "Mask for route not entered\n"); 536 return (NULL); 537 } 538 bzero(m, sizeof *m); 539 m->rm_bit = tt->rn_bit; 540 m->rm_flags = tt->rn_flags; 541 if (tt->rn_flags & RNF_NORMAL) 542 m->rm_leaf = tt; 543 else 544 m->rm_mask = tt->rn_mask; 545 m->rm_next = nextmask; 546 tt->rn_mklist = m; 547 return m; 548 } 549 550 struct radix_node * 551 rn_addroute(char *key, char *netmask, struct radix_node_head *head, 552 struct radix_node treenodes[2]) 553 { 554 struct radix_node *t, *x = NULL, *tt; 555 struct radix_node *saved_tt, *top = head->rnh_treetop; 556 short b = 0, b_leaf = 0; 557 boolean_t keyduplicated; 558 char *mmask; 559 struct radix_mask *m, **mp; 560 561 /* 562 * In dealing with non-contiguous masks, there may be 563 * many different routes which have the same mask. 564 * We will find it useful to have a unique pointer to 565 * the mask to speed avoiding duplicate references at 566 * nodes and possibly save time in calculating indices. 567 */ 568 if (netmask != NULL) { 569 if ((x = rn_addmask(netmask, FALSE, top->rn_offset)) == NULL) 570 return (NULL); 571 b_leaf = x->rn_bit; 572 b = -1 - x->rn_bit; 573 netmask = x->rn_key; 574 } 575 /* 576 * Deal with duplicated keys: attach node to previous instance 577 */ 578 saved_tt = tt = rn_insert(key, head, &keyduplicated, treenodes); 579 if (keyduplicated) { 580 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 581 if (tt->rn_mask == netmask) 582 return (NULL); 583 if (netmask == NULL || 584 (tt->rn_mask && 585 ((b_leaf < tt->rn_bit) /* index(netmask) > node */ 586 || rn_refines(netmask, tt->rn_mask) 587 || rn_lexobetter(netmask, tt->rn_mask)))) 588 break; 589 } 590 /* 591 * If the mask is not duplicated, we wouldn't 592 * find it among possible duplicate key entries 593 * anyway, so the above test doesn't hurt. 594 * 595 * We sort the masks for a duplicated key the same way as 596 * in a masklist -- most specific to least specific. 597 * This may require the unfortunate nuisance of relocating 598 * the head of the list. 599 */ 600 if (tt == saved_tt) { 601 struct radix_node *xx = x; 602 /* link in at head of list */ 603 (tt = treenodes)->rn_dupedkey = t; 604 tt->rn_flags = t->rn_flags; 605 tt->rn_parent = x = t->rn_parent; 606 t->rn_parent = tt; /* parent */ 607 if (x->rn_left == t) 608 x->rn_left = tt; 609 else 610 x->rn_right = tt; 611 saved_tt = tt; x = xx; 612 } else { 613 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 614 t->rn_dupedkey = tt; 615 tt->rn_parent = t; /* parent */ 616 if (tt->rn_dupedkey != NULL) /* parent */ 617 tt->rn_dupedkey->rn_parent = tt; /* parent */ 618 } 619 #ifdef RN_DEBUG 620 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 621 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 622 #endif 623 tt->rn_key = key; 624 tt->rn_bit = -1; 625 tt->rn_flags = RNF_ACTIVE; 626 } 627 /* 628 * Put mask in tree. 629 */ 630 if (netmask != NULL) { 631 tt->rn_mask = netmask; 632 tt->rn_bit = x->rn_bit; 633 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 634 } 635 t = saved_tt->rn_parent; 636 if (keyduplicated) 637 goto on2; 638 b_leaf = -1 - t->rn_bit; 639 if (t->rn_right == saved_tt) 640 x = t->rn_left; 641 else 642 x = t->rn_right; 643 /* Promote general routes from below */ 644 if (x->rn_bit < 0) { 645 mp = &t->rn_mklist; 646 while (x != NULL) { 647 if (x->rn_mask != NULL && 648 x->rn_bit >= b_leaf && 649 x->rn_mklist == NULL) { 650 *mp = m = rn_new_radix_mask(x, NULL); 651 if (m != NULL) 652 mp = &m->rm_next; 653 } 654 x = x->rn_dupedkey; 655 } 656 } else if (x->rn_mklist != NULL) { 657 /* 658 * Skip over masks whose index is > that of new node 659 */ 660 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) 661 if (m->rm_bit >= b_leaf) 662 break; 663 t->rn_mklist = m; 664 *mp = NULL; 665 } 666 on2: 667 /* Add new route to highest possible ancestor's list */ 668 if ((netmask == NULL) || (b > t->rn_bit )) 669 return tt; /* can't lift at all */ 670 b_leaf = tt->rn_bit; 671 do { 672 x = t; 673 t = t->rn_parent; 674 } while (b <= t->rn_bit && x != top); 675 /* 676 * Search through routes associated with node to 677 * insert new route according to index. 678 * Need same criteria as when sorting dupedkeys to avoid 679 * double loop on deletion. 680 */ 681 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) { 682 if (m->rm_bit < b_leaf) 683 continue; 684 if (m->rm_bit > b_leaf) 685 break; 686 if (m->rm_flags & RNF_NORMAL) { 687 mmask = m->rm_leaf->rn_mask; 688 if (tt->rn_flags & RNF_NORMAL) { 689 log(LOG_ERR, 690 "Non-unique normal route, mask not entered\n"); 691 return tt; 692 } 693 } else 694 mmask = m->rm_mask; 695 if (mmask == netmask) { 696 m->rm_refs++; 697 tt->rn_mklist = m; 698 return tt; 699 } 700 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 701 break; 702 } 703 *mp = rn_new_radix_mask(tt, *mp); 704 return tt; 705 } 706 707 struct radix_node * 708 rn_delete(char *key, char *netmask, struct radix_node_head *head) 709 { 710 struct radix_node *t, *p, *x, *tt; 711 struct radix_mask *m, *saved_m, **mp; 712 struct radix_node *dupedkey, *saved_tt, *top; 713 int b, head_off, klen; 714 715 x = head->rnh_treetop; 716 tt = rn_search(key, x); 717 head_off = x->rn_offset; 718 klen = clen(key); 719 saved_tt = tt; 720 top = x; 721 if (tt == NULL || 722 bcmp(key + head_off, tt->rn_key + head_off, klen - head_off)) 723 return (NULL); 724 /* 725 * Delete our route from mask lists. 726 */ 727 if (netmask != NULL) { 728 if ((x = rn_addmask(netmask, TRUE, head_off)) == NULL) 729 return (NULL); 730 netmask = x->rn_key; 731 while (tt->rn_mask != netmask) 732 if ((tt = tt->rn_dupedkey) == NULL) 733 return (NULL); 734 } 735 if (tt->rn_mask == NULL || (saved_m = m = tt->rn_mklist) == NULL) 736 goto on1; 737 if (tt->rn_flags & RNF_NORMAL) { 738 if (m->rm_leaf != tt || m->rm_refs > 0) { 739 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 740 return (NULL); /* dangling ref could cause disaster */ 741 } 742 } else { 743 if (m->rm_mask != tt->rn_mask) { 744 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 745 goto on1; 746 } 747 if (--m->rm_refs >= 0) 748 goto on1; 749 } 750 b = -1 - tt->rn_bit; 751 t = saved_tt->rn_parent; 752 if (b > t->rn_bit) 753 goto on1; /* Wasn't lifted at all */ 754 do { 755 x = t; 756 t = t->rn_parent; 757 } while (b <= t->rn_bit && x != top); 758 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_next) 759 if (m == saved_m) { 760 *mp = m->rm_next; 761 MKFree(&rn_mkfreelist, m); 762 break; 763 } 764 if (m == NULL) { 765 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 766 if (tt->rn_flags & RNF_NORMAL) 767 return (NULL); /* Dangling ref to us */ 768 } 769 on1: 770 /* 771 * Eliminate us from tree 772 */ 773 if (tt->rn_flags & RNF_ROOT) 774 return (NULL); 775 #ifdef RN_DEBUG 776 /* Get us out of the creation list */ 777 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 778 if (t) t->rn_ybro = tt->rn_ybro; 779 #endif 780 t = tt->rn_parent; 781 dupedkey = saved_tt->rn_dupedkey; 782 if (dupedkey != NULL) { 783 /* 784 * at this point, tt is the deletion target and saved_tt 785 * is the head of the dupekey chain 786 */ 787 if (tt == saved_tt) { 788 /* remove from head of chain */ 789 x = dupedkey; x->rn_parent = t; 790 if (t->rn_left == tt) 791 t->rn_left = x; 792 else 793 t->rn_right = x; 794 } else { 795 /* find node in front of tt on the chain */ 796 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 797 p = p->rn_dupedkey; 798 if (p) { 799 p->rn_dupedkey = tt->rn_dupedkey; 800 if (tt->rn_dupedkey) /* parent */ 801 tt->rn_dupedkey->rn_parent = p; 802 /* parent */ 803 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 804 } 805 t = tt + 1; 806 if (t->rn_flags & RNF_ACTIVE) { 807 #ifndef RN_DEBUG 808 *++x = *t; 809 p = t->rn_parent; 810 #else 811 b = t->rn_info; 812 *++x = *t; 813 t->rn_info = b; 814 p = t->rn_parent; 815 #endif 816 if (p->rn_left == t) 817 p->rn_left = x; 818 else 819 p->rn_right = x; 820 x->rn_left->rn_parent = x; 821 x->rn_right->rn_parent = x; 822 } 823 goto out; 824 } 825 if (t->rn_left == tt) 826 x = t->rn_right; 827 else 828 x = t->rn_left; 829 p = t->rn_parent; 830 if (p->rn_right == t) 831 p->rn_right = x; 832 else 833 p->rn_left = x; 834 x->rn_parent = p; 835 /* 836 * Demote routes attached to us. 837 */ 838 if (t->rn_mklist != NULL) { 839 if (x->rn_bit >= 0) { 840 for (mp = &x->rn_mklist; (m = *mp);) 841 mp = &m->rm_next; 842 *mp = t->rn_mklist; 843 } else { 844 /* 845 * If there are any (key, mask) pairs in a sibling 846 * duped-key chain, some subset will appear sorted 847 * in the same order attached to our mklist. 848 */ 849 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 850 if (m == x->rn_mklist) { 851 struct radix_mask *mm = m->rm_next; 852 853 x->rn_mklist = NULL; 854 if (--(m->rm_refs) < 0) 855 MKFree(&rn_mkfreelist, m); 856 m = mm; 857 } 858 if (m) 859 log(LOG_ERR, 860 "rn_delete: Orphaned Mask %p at %p\n", 861 (void *)m, (void *)x); 862 } 863 } 864 /* 865 * We may be holding an active internal node in the tree. 866 */ 867 x = tt + 1; 868 if (t != x) { 869 #ifndef RN_DEBUG 870 *t = *x; 871 #else 872 b = t->rn_info; 873 *t = *x; 874 t->rn_info = b; 875 #endif 876 t->rn_left->rn_parent = t; 877 t->rn_right->rn_parent = t; 878 p = x->rn_parent; 879 if (p->rn_left == x) 880 p->rn_left = t; 881 else 882 p->rn_right = t; 883 } 884 out: 885 tt->rn_flags &= ~RNF_ACTIVE; 886 tt[1].rn_flags &= ~RNF_ACTIVE; 887 return (tt); 888 } 889 890 /* 891 * This is the same as rn_walktree() except for the parameters and the 892 * exit. 893 */ 894 static int 895 rn_walktree_from(struct radix_node_head *h, char *xa, char *xm, 896 walktree_f_t *f, void *w) 897 { 898 struct radix_node *base, *next; 899 struct radix_node *rn, *last = NULL /* shut up gcc */; 900 boolean_t stopping = FALSE; 901 int lastb, error; 902 903 /* 904 * rn_search_m is sort-of-open-coded here. 905 */ 906 /* kprintf("about to search\n"); */ 907 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) { 908 last = rn; 909 /* kprintf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n", 910 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */ 911 if (!(rn->rn_bmask & xm[rn->rn_offset])) { 912 break; 913 } 914 if (rn->rn_bmask & xa[rn->rn_offset]) { 915 rn = rn->rn_right; 916 } else { 917 rn = rn->rn_left; 918 } 919 } 920 /* kprintf("done searching\n"); */ 921 922 /* 923 * Two cases: either we stepped off the end of our mask, 924 * in which case last == rn, or we reached a leaf, in which 925 * case we want to start from the last node we looked at. 926 * Either way, last is the node we want to start from. 927 */ 928 rn = last; 929 lastb = rn->rn_bit; 930 931 /* kprintf("rn %p, lastb %d\n", rn, lastb);*/ 932 933 /* 934 * This gets complicated because we may delete the node 935 * while applying the function f to it, so we need to calculate 936 * the successor node in advance. 937 */ 938 while (rn->rn_bit >= 0) 939 rn = rn->rn_left; 940 941 while (!stopping) { 942 /* kprintf("node %p (%d)\n", rn, rn->rn_bit); */ 943 base = rn; 944 /* If at right child go back up, otherwise, go right */ 945 while (rn->rn_parent->rn_right == rn && 946 !(rn->rn_flags & RNF_ROOT)) { 947 rn = rn->rn_parent; 948 949 /* if went up beyond last, stop */ 950 if (rn->rn_bit < lastb) { 951 stopping = TRUE; 952 /* kprintf("up too far\n"); */ 953 } 954 } 955 956 /* Find the next *leaf* since next node might vanish, too */ 957 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 958 rn = rn->rn_left; 959 next = rn; 960 /* Process leaves */ 961 while ((rn = base) != NULL) { 962 base = rn->rn_dupedkey; 963 /* kprintf("leaf %p\n", rn); */ 964 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 965 return (error); 966 } 967 rn = next; 968 969 if (rn->rn_flags & RNF_ROOT) { 970 /* kprintf("root, stopping"); */ 971 stopping = TRUE; 972 } 973 974 } 975 return 0; 976 } 977 978 static int 979 rn_walktree(struct radix_node_head *h, walktree_f_t *f, void *w) 980 { 981 struct radix_node *base, *next; 982 struct radix_node *rn = h->rnh_treetop; 983 int error; 984 985 /* 986 * This gets complicated because we may delete the node 987 * while applying the function f to it, so we need to calculate 988 * the successor node in advance. 989 */ 990 /* First time through node, go left */ 991 while (rn->rn_bit >= 0) 992 rn = rn->rn_left; 993 for (;;) { 994 base = rn; 995 /* If at right child go back up, otherwise, go right */ 996 while (rn->rn_parent->rn_right == rn && 997 !(rn->rn_flags & RNF_ROOT)) 998 rn = rn->rn_parent; 999 /* Find the next *leaf* since next node might vanish, too */ 1000 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;) 1001 rn = rn->rn_left; 1002 next = rn; 1003 /* Process leaves */ 1004 while ((rn = base)) { 1005 base = rn->rn_dupedkey; 1006 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 1007 return (error); 1008 } 1009 rn = next; 1010 if (rn->rn_flags & RNF_ROOT) 1011 return (0); 1012 } 1013 /* NOTREACHED */ 1014 } 1015 1016 int 1017 rn_inithead(void **head, int off) 1018 { 1019 struct radix_node_head *rnh; 1020 struct radix_node *root, *left, *right; 1021 1022 if (*head != NULL) /* already initialized */ 1023 return (1); 1024 1025 R_Malloc(rnh, struct radix_node_head *, sizeof *rnh); 1026 if (rnh == NULL) 1027 return (0); 1028 bzero(rnh, sizeof *rnh); 1029 *head = rnh; 1030 1031 root = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1032 right = &rnh->rnh_nodes[2]; 1033 root->rn_parent = root; 1034 root->rn_flags = RNF_ROOT | RNF_ACTIVE; 1035 root->rn_right = right; 1036 1037 left = root->rn_left; 1038 left->rn_bit = -1 - off; 1039 left->rn_flags = RNF_ROOT | RNF_ACTIVE; 1040 1041 *right = *left; 1042 right->rn_key = rn_ones; 1043 1044 rnh->rnh_treetop = root; 1045 1046 rnh->rnh_addaddr = rn_addroute; 1047 rnh->rnh_deladdr = rn_delete; 1048 rnh->rnh_matchaddr = rn_match; 1049 rnh->rnh_lookup = rn_lookup; 1050 rnh->rnh_walktree = rn_walktree; 1051 rnh->rnh_walktree_from = rn_walktree_from; 1052 1053 return (1); 1054 } 1055 1056 void 1057 rn_init(void) 1058 { 1059 char *cp, *cplim; 1060 int cpu; 1061 #ifdef _KERNEL 1062 struct domain *dom; 1063 1064 SLIST_FOREACH(dom, &domains, dom_next) 1065 if (dom->dom_maxrtkey > max_keylen) 1066 max_keylen = dom->dom_maxrtkey; 1067 #endif 1068 if (max_keylen == 0) { 1069 log(LOG_ERR, 1070 "rn_init: radix functions require max_keylen be set\n"); 1071 return; 1072 } 1073 R_Malloc(rn_zeros, char *, 2 * max_keylen); 1074 if (rn_zeros == NULL) 1075 panic("rn_init"); 1076 bzero(rn_zeros, 2 * max_keylen); 1077 rn_ones = cp = rn_zeros + max_keylen; 1078 cplim = rn_ones + max_keylen; 1079 while (cp < cplim) 1080 *cp++ = -1; 1081 1082 for (cpu = 0; cpu < ncpus; ++cpu) { 1083 if (rn_inithead((void **)&mask_rnheads[cpu], 0) == 0) 1084 panic("rn_init 2"); 1085 } 1086 } 1087