1 /* $NetBSD: radix.c,v 1.40 2008/11/25 18:28:06 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)radix.c 8.6 (Berkeley) 10/17/95 32 */ 33 34 /* 35 * Routines to build and maintain radix trees for routing lookups. 36 */ 37 38 #include <sys/cdefs.h> 39 __KERNEL_RCSID(0, "$NetBSD: radix.c,v 1.40 2008/11/25 18:28:06 pooka Exp $"); 40 41 #ifndef _NET_RADIX_H_ 42 #include <sys/param.h> 43 #ifdef _KERNEL 44 #include "opt_inet.h" 45 46 #include <sys/systm.h> 47 #include <sys/malloc.h> 48 #define M_DONTWAIT M_NOWAIT 49 #include <sys/domain.h> 50 #else 51 #include <stdlib.h> 52 #endif 53 #include <machine/stdarg.h> 54 #include <sys/syslog.h> 55 #include <net/radix.h> 56 #endif 57 58 typedef void (*rn_printer_t)(void *, const char *fmt, ...); 59 60 int max_keylen; 61 struct radix_mask *rn_mkfreelist; 62 struct radix_node_head *mask_rnhead; 63 static char *addmask_key; 64 static const char normal_chars[] = 65 {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 66 static char *rn_zeros, *rn_ones; 67 68 #define rn_masktop (mask_rnhead->rnh_treetop) 69 70 static int rn_satisfies_leaf(const char *, struct radix_node *, int); 71 static int rn_lexobetter(const void *, const void *); 72 static struct radix_mask *rn_new_radix_mask(struct radix_node *, 73 struct radix_mask *); 74 static struct radix_node *rn_walknext(struct radix_node *, rn_printer_t, 75 void *); 76 static struct radix_node *rn_walkfirst(struct radix_node *, rn_printer_t, 77 void *); 78 static void rn_nodeprint(struct radix_node *, rn_printer_t, void *, 79 const char *); 80 81 #define SUBTREE_OPEN "[ " 82 #define SUBTREE_CLOSE " ]" 83 84 #ifdef RN_DEBUG 85 static void rn_treeprint(struct radix_node_head *, rn_printer_t, void *); 86 #endif /* RN_DEBUG */ 87 88 /* 89 * The data structure for the keys is a radix tree with one way 90 * branching removed. The index rn_b at an internal node n represents a bit 91 * position to be tested. The tree is arranged so that all descendants 92 * of a node n have keys whose bits all agree up to position rn_b - 1. 93 * (We say the index of n is rn_b.) 94 * 95 * There is at least one descendant which has a one bit at position rn_b, 96 * and at least one with a zero there. 97 * 98 * A route is determined by a pair of key and mask. We require that the 99 * bit-wise logical and of the key and mask to be the key. 100 * We define the index of a route to associated with the mask to be 101 * the first bit number in the mask where 0 occurs (with bit number 0 102 * representing the highest order bit). 103 * 104 * We say a mask is normal if every bit is 0, past the index of the mask. 105 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 106 * and m is a normal mask, then the route applies to every descendant of n. 107 * If the index(m) < rn_b, this implies the trailing last few bits of k 108 * before bit b are all 0, (and hence consequently true of every descendant 109 * of n), so the route applies to all descendants of the node as well. 110 * 111 * Similar logic shows that a non-normal mask m such that 112 * index(m) <= index(n) could potentially apply to many children of n. 113 * Thus, for each non-host route, we attach its mask to a list at an internal 114 * node as high in the tree as we can go. 115 * 116 * The present version of the code makes use of normal routes in short- 117 * circuiting an explicit mask and compare operation when testing whether 118 * a key satisfies a normal route, and also in remembering the unique leaf 119 * that governs a subtree. 120 */ 121 122 struct radix_node * 123 rn_search( 124 const void *v_arg, 125 struct radix_node *head) 126 { 127 const u_char * const v = v_arg; 128 struct radix_node *x; 129 130 for (x = head; x->rn_b >= 0;) { 131 if (x->rn_bmask & v[x->rn_off]) 132 x = x->rn_r; 133 else 134 x = x->rn_l; 135 } 136 return x; 137 } 138 139 struct radix_node * 140 rn_search_m( 141 const void *v_arg, 142 struct radix_node *head, 143 const void *m_arg) 144 { 145 struct radix_node *x; 146 const u_char * const v = v_arg; 147 const u_char * const m = m_arg; 148 149 for (x = head; x->rn_b >= 0;) { 150 if ((x->rn_bmask & m[x->rn_off]) && 151 (x->rn_bmask & v[x->rn_off])) 152 x = x->rn_r; 153 else 154 x = x->rn_l; 155 } 156 return x; 157 } 158 159 int 160 rn_refines( 161 const void *m_arg, 162 const void *n_arg) 163 { 164 const char *m = m_arg; 165 const char *n = n_arg; 166 const char *lim = n + *(const u_char *)n; 167 const char *lim2 = lim; 168 int longer = (*(const u_char *)n++) - (int)(*(const u_char *)m++); 169 int masks_are_equal = 1; 170 171 if (longer > 0) 172 lim -= longer; 173 while (n < lim) { 174 if (*n & ~(*m)) 175 return 0; 176 if (*n++ != *m++) 177 masks_are_equal = 0; 178 } 179 while (n < lim2) 180 if (*n++) 181 return 0; 182 if (masks_are_equal && (longer < 0)) 183 for (lim2 = m - longer; m < lim2; ) 184 if (*m++) 185 return 1; 186 return !masks_are_equal; 187 } 188 189 struct radix_node * 190 rn_lookup( 191 const void *v_arg, 192 const void *m_arg, 193 struct radix_node_head *head) 194 { 195 struct radix_node *x; 196 const char *netmask = NULL; 197 198 if (m_arg) { 199 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 200 return NULL; 201 netmask = x->rn_key; 202 } 203 x = rn_match(v_arg, head); 204 if (x != NULL && netmask != NULL) { 205 while (x != NULL && x->rn_mask != netmask) 206 x = x->rn_dupedkey; 207 } 208 return x; 209 } 210 211 static int 212 rn_satisfies_leaf( 213 const char *trial, 214 struct radix_node *leaf, 215 int skip) 216 { 217 const char *cp = trial; 218 const char *cp2 = leaf->rn_key; 219 const char *cp3 = leaf->rn_mask; 220 const char *cplim; 221 int length = min(*(const u_char *)cp, *(const u_char *)cp2); 222 223 if (cp3 == 0) 224 cp3 = rn_ones; 225 else 226 length = min(length, *(const u_char *)cp3); 227 cplim = cp + length; cp3 += skip; cp2 += skip; 228 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 229 if ((*cp ^ *cp2) & *cp3) 230 return 0; 231 return 1; 232 } 233 234 struct radix_node * 235 rn_match( 236 const void *v_arg, 237 struct radix_node_head *head) 238 { 239 const char * const v = v_arg; 240 struct radix_node *t = head->rnh_treetop; 241 struct radix_node *top = t; 242 struct radix_node *x; 243 struct radix_node *saved_t; 244 const char *cp = v; 245 const char *cp2; 246 const char *cplim; 247 int off = t->rn_off; 248 int vlen = *(const u_char *)cp; 249 int matched_off; 250 int test, b, rn_b; 251 252 /* 253 * Open code rn_search(v, top) to avoid overhead of extra 254 * subroutine call. 255 */ 256 for (; t->rn_b >= 0; ) { 257 if (t->rn_bmask & cp[t->rn_off]) 258 t = t->rn_r; 259 else 260 t = t->rn_l; 261 } 262 /* 263 * See if we match exactly as a host destination 264 * or at least learn how many bits match, for normal mask finesse. 265 * 266 * It doesn't hurt us to limit how many bytes to check 267 * to the length of the mask, since if it matches we had a genuine 268 * match and the leaf we have is the most specific one anyway; 269 * if it didn't match with a shorter length it would fail 270 * with a long one. This wins big for class B&C netmasks which 271 * are probably the most common case... 272 */ 273 if (t->rn_mask) 274 vlen = *(const u_char *)t->rn_mask; 275 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 276 for (; cp < cplim; cp++, cp2++) 277 if (*cp != *cp2) 278 goto on1; 279 /* 280 * This extra grot is in case we are explicitly asked 281 * to look up the default. Ugh! 282 */ 283 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 284 t = t->rn_dupedkey; 285 return t; 286 on1: 287 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 288 for (b = 7; (test >>= 1) > 0;) 289 b--; 290 matched_off = cp - v; 291 b += matched_off << 3; 292 rn_b = -1 - b; 293 /* 294 * If there is a host route in a duped-key chain, it will be first. 295 */ 296 if ((saved_t = t)->rn_mask == 0) 297 t = t->rn_dupedkey; 298 for (; t; t = t->rn_dupedkey) 299 /* 300 * Even if we don't match exactly as a host, 301 * we may match if the leaf we wound up at is 302 * a route to a net. 303 */ 304 if (t->rn_flags & RNF_NORMAL) { 305 if (rn_b <= t->rn_b) 306 return t; 307 } else if (rn_satisfies_leaf(v, t, matched_off)) 308 return t; 309 t = saved_t; 310 /* start searching up the tree */ 311 do { 312 struct radix_mask *m; 313 t = t->rn_p; 314 m = t->rn_mklist; 315 if (m) { 316 /* 317 * If non-contiguous masks ever become important 318 * we can restore the masking and open coding of 319 * the search and satisfaction test and put the 320 * calculation of "off" back before the "do". 321 */ 322 do { 323 if (m->rm_flags & RNF_NORMAL) { 324 if (rn_b <= m->rm_b) 325 return m->rm_leaf; 326 } else { 327 off = min(t->rn_off, matched_off); 328 x = rn_search_m(v, t, m->rm_mask); 329 while (x && x->rn_mask != m->rm_mask) 330 x = x->rn_dupedkey; 331 if (x && rn_satisfies_leaf(v, x, off)) 332 return x; 333 } 334 m = m->rm_mklist; 335 } while (m); 336 } 337 } while (t != top); 338 return NULL; 339 } 340 341 static void 342 rn_nodeprint(struct radix_node *rn, rn_printer_t printer, void *arg, 343 const char *delim) 344 { 345 (*printer)(arg, "%s(%s%p: p<%p> l<%p> r<%p>)", 346 delim, ((void *)rn == arg) ? "*" : "", rn, rn->rn_p, 347 rn->rn_l, rn->rn_r); 348 } 349 350 #ifdef RN_DEBUG 351 int rn_debug = 1; 352 353 static void 354 rn_dbg_print(void *arg, const char *fmt, ...) 355 { 356 va_list ap; 357 358 va_start(ap, fmt); 359 vlog(LOG_DEBUG, fmt, ap); 360 va_end(ap); 361 } 362 363 static void 364 rn_treeprint(struct radix_node_head *h, rn_printer_t printer, void *arg) 365 { 366 struct radix_node *dup, *rn; 367 const char *delim; 368 369 if (printer == NULL) 370 return; 371 372 rn = rn_walkfirst(h->rnh_treetop, printer, arg); 373 for (;;) { 374 /* Process leaves */ 375 delim = ""; 376 for (dup = rn; dup != NULL; dup = dup->rn_dupedkey) { 377 if ((dup->rn_flags & RNF_ROOT) != 0) 378 continue; 379 rn_nodeprint(dup, printer, arg, delim); 380 delim = ", "; 381 } 382 rn = rn_walknext(rn, printer, arg); 383 if (rn->rn_flags & RNF_ROOT) 384 return; 385 } 386 /* NOTREACHED */ 387 } 388 389 #define traverse(__head, __rn) rn_treeprint((__head), rn_dbg_print, (__rn)) 390 #endif /* RN_DEBUG */ 391 392 struct radix_node * 393 rn_newpair( 394 const void *v, 395 int b, 396 struct radix_node nodes[2]) 397 { 398 struct radix_node *tt = nodes; 399 struct radix_node *t = tt + 1; 400 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 401 t->rn_l = tt; t->rn_off = b >> 3; 402 tt->rn_b = -1; tt->rn_key = v; tt->rn_p = t; 403 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 404 return t; 405 } 406 407 struct radix_node * 408 rn_insert( 409 const void *v_arg, 410 struct radix_node_head *head, 411 int *dupentry, 412 struct radix_node nodes[2]) 413 { 414 struct radix_node *top = head->rnh_treetop; 415 struct radix_node *t = rn_search(v_arg, top); 416 struct radix_node *tt; 417 const char *v = v_arg; 418 int head_off = top->rn_off; 419 int vlen = *((const u_char *)v); 420 const char *cp = v + head_off; 421 int b; 422 /* 423 * Find first bit at which v and t->rn_key differ 424 */ 425 { 426 const char *cp2 = t->rn_key + head_off; 427 const char *cplim = v + vlen; 428 int cmp_res; 429 430 while (cp < cplim) 431 if (*cp2++ != *cp++) 432 goto on1; 433 *dupentry = 1; 434 return t; 435 on1: 436 *dupentry = 0; 437 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 438 for (b = (cp - v) << 3; cmp_res; b--) 439 cmp_res >>= 1; 440 } 441 { 442 struct radix_node *p, *x = top; 443 cp = v; 444 do { 445 p = x; 446 if (cp[x->rn_off] & x->rn_bmask) 447 x = x->rn_r; 448 else x = x->rn_l; 449 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 450 #ifdef RN_DEBUG 451 if (rn_debug) 452 log(LOG_DEBUG, "%s: Going In:\n", __func__), traverse(head, p); 453 #endif 454 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 455 if ((cp[p->rn_off] & p->rn_bmask) == 0) 456 p->rn_l = t; 457 else 458 p->rn_r = t; 459 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 460 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 461 t->rn_r = x; 462 } else { 463 t->rn_r = tt; t->rn_l = x; 464 } 465 #ifdef RN_DEBUG 466 if (rn_debug) { 467 log(LOG_DEBUG, "%s: Coming Out:\n", __func__), 468 traverse(head, p); 469 } 470 #endif /* RN_DEBUG */ 471 } 472 return tt; 473 } 474 475 struct radix_node * 476 rn_addmask( 477 const void *n_arg, 478 int search, 479 int skip) 480 { 481 const char *netmask = n_arg; 482 const char *cp; 483 const char *cplim; 484 struct radix_node *x; 485 struct radix_node *saved_x; 486 int b = 0, mlen, j; 487 int maskduplicated, m0, isnormal; 488 static int last_zeroed = 0; 489 490 if ((mlen = *(const u_char *)netmask) > max_keylen) 491 mlen = max_keylen; 492 if (skip == 0) 493 skip = 1; 494 if (mlen <= skip) 495 return mask_rnhead->rnh_nodes; 496 if (skip > 1) 497 memmove(addmask_key + 1, rn_ones + 1, skip - 1); 498 if ((m0 = mlen) > skip) 499 memmove(addmask_key + skip, netmask + skip, mlen - skip); 500 /* 501 * Trim trailing zeroes. 502 */ 503 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 504 cp--; 505 mlen = cp - addmask_key; 506 if (mlen <= skip) { 507 if (m0 >= last_zeroed) 508 last_zeroed = mlen; 509 return mask_rnhead->rnh_nodes; 510 } 511 if (m0 < last_zeroed) 512 memset(addmask_key + m0, 0, last_zeroed - m0); 513 *addmask_key = last_zeroed = mlen; 514 x = rn_search(addmask_key, rn_masktop); 515 if (memcmp(addmask_key, x->rn_key, mlen) != 0) 516 x = 0; 517 if (x || search) 518 return x; 519 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 520 if ((saved_x = x) == NULL) 521 return NULL; 522 memset(x, 0, max_keylen + 2 * sizeof (*x)); 523 cp = netmask = (void *)(x + 2); 524 memmove(x + 2, addmask_key, mlen); 525 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 526 if (maskduplicated) { 527 log(LOG_ERR, "rn_addmask: mask impossibly already in tree\n"); 528 Free(saved_x); 529 return x; 530 } 531 /* 532 * Calculate index of mask, and check for normalcy. 533 */ 534 cplim = netmask + mlen; isnormal = 1; 535 for (cp = netmask + skip; (cp < cplim) && *(const u_char *)cp == 0xff;) 536 cp++; 537 if (cp != cplim) { 538 for (j = 0x80; (j & *cp) != 0; j >>= 1) 539 b++; 540 if (*cp != normal_chars[b] || cp != (cplim - 1)) 541 isnormal = 0; 542 } 543 b += (cp - netmask) << 3; 544 x->rn_b = -1 - b; 545 if (isnormal) 546 x->rn_flags |= RNF_NORMAL; 547 return x; 548 } 549 550 static int /* XXX: arbitrary ordering for non-contiguous masks */ 551 rn_lexobetter( 552 const void *m_arg, 553 const void *n_arg) 554 { 555 const u_char *mp = m_arg; 556 const u_char *np = n_arg; 557 const u_char *lim; 558 559 if (*mp > *np) 560 return 1; /* not really, but need to check longer one first */ 561 if (*mp == *np) 562 for (lim = mp + *mp; mp < lim;) 563 if (*mp++ > *np++) 564 return 1; 565 return 0; 566 } 567 568 static struct radix_mask * 569 rn_new_radix_mask( 570 struct radix_node *tt, 571 struct radix_mask *next) 572 { 573 struct radix_mask *m; 574 575 MKGet(m); 576 if (m == NULL) { 577 log(LOG_ERR, "Mask for route not entered\n"); 578 return NULL; 579 } 580 memset(m, 0, sizeof(*m)); 581 m->rm_b = tt->rn_b; 582 m->rm_flags = tt->rn_flags; 583 if (tt->rn_flags & RNF_NORMAL) 584 m->rm_leaf = tt; 585 else 586 m->rm_mask = tt->rn_mask; 587 m->rm_mklist = next; 588 tt->rn_mklist = m; 589 return m; 590 } 591 592 struct radix_node * 593 rn_addroute( 594 const void *v_arg, 595 const void *n_arg, 596 struct radix_node_head *head, 597 struct radix_node treenodes[2]) 598 { 599 const char *v = v_arg, *netmask = n_arg; 600 struct radix_node *t, *x = NULL, *tt; 601 struct radix_node *saved_tt, *top = head->rnh_treetop; 602 short b = 0, b_leaf = 0; 603 int keyduplicated; 604 const char *mmask; 605 struct radix_mask *m, **mp; 606 607 /* 608 * In dealing with non-contiguous masks, there may be 609 * many different routes which have the same mask. 610 * We will find it useful to have a unique pointer to 611 * the mask to speed avoiding duplicate references at 612 * nodes and possibly save time in calculating indices. 613 */ 614 if (netmask != NULL) { 615 if ((x = rn_addmask(netmask, 0, top->rn_off)) == NULL) 616 return NULL; 617 b_leaf = x->rn_b; 618 b = -1 - x->rn_b; 619 netmask = x->rn_key; 620 } 621 /* 622 * Deal with duplicated keys: attach node to previous instance 623 */ 624 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 625 if (keyduplicated) { 626 for (t = tt; tt != NULL; t = tt, tt = tt->rn_dupedkey) { 627 if (tt->rn_mask == netmask) 628 return NULL; 629 if (netmask == NULL || 630 (tt->rn_mask != NULL && 631 (b_leaf < tt->rn_b || /* index(netmask) > node */ 632 rn_refines(netmask, tt->rn_mask) || 633 rn_lexobetter(netmask, tt->rn_mask)))) 634 break; 635 } 636 /* 637 * If the mask is not duplicated, we wouldn't 638 * find it among possible duplicate key entries 639 * anyway, so the above test doesn't hurt. 640 * 641 * We sort the masks for a duplicated key the same way as 642 * in a masklist -- most specific to least specific. 643 * This may require the unfortunate nuisance of relocating 644 * the head of the list. 645 * 646 * We also reverse, or doubly link the list through the 647 * parent pointer. 648 */ 649 if (tt == saved_tt) { 650 struct radix_node *xx = x; 651 /* link in at head of list */ 652 (tt = treenodes)->rn_dupedkey = t; 653 tt->rn_flags = t->rn_flags; 654 tt->rn_p = x = t->rn_p; 655 t->rn_p = tt; 656 if (x->rn_l == t) 657 x->rn_l = tt; 658 else 659 x->rn_r = tt; 660 saved_tt = tt; 661 x = xx; 662 } else { 663 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 664 t->rn_dupedkey = tt; 665 tt->rn_p = t; 666 if (tt->rn_dupedkey) 667 tt->rn_dupedkey->rn_p = tt; 668 } 669 tt->rn_key = v; 670 tt->rn_b = -1; 671 tt->rn_flags = RNF_ACTIVE; 672 } 673 /* 674 * Put mask in tree. 675 */ 676 if (netmask != NULL) { 677 tt->rn_mask = netmask; 678 tt->rn_b = x->rn_b; 679 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 680 } 681 t = saved_tt->rn_p; 682 if (keyduplicated) 683 goto on2; 684 b_leaf = -1 - t->rn_b; 685 if (t->rn_r == saved_tt) 686 x = t->rn_l; 687 else 688 x = t->rn_r; 689 /* Promote general routes from below */ 690 if (x->rn_b < 0) { 691 for (mp = &t->rn_mklist; x != NULL; x = x->rn_dupedkey) { 692 if (x->rn_mask != NULL && x->rn_b >= b_leaf && 693 x->rn_mklist == NULL) { 694 *mp = m = rn_new_radix_mask(x, NULL); 695 if (m != NULL) 696 mp = &m->rm_mklist; 697 } 698 } 699 } else if (x->rn_mklist != NULL) { 700 /* 701 * Skip over masks whose index is > that of new node 702 */ 703 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 704 if (m->rm_b >= b_leaf) 705 break; 706 t->rn_mklist = m; 707 *mp = NULL; 708 } 709 on2: 710 /* Add new route to highest possible ancestor's list */ 711 if (netmask == NULL || b > t->rn_b) 712 return tt; /* can't lift at all */ 713 b_leaf = tt->rn_b; 714 do { 715 x = t; 716 t = t->rn_p; 717 } while (b <= t->rn_b && x != top); 718 /* 719 * Search through routes associated with node to 720 * insert new route according to index. 721 * Need same criteria as when sorting dupedkeys to avoid 722 * double loop on deletion. 723 */ 724 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { 725 if (m->rm_b < b_leaf) 726 continue; 727 if (m->rm_b > b_leaf) 728 break; 729 if (m->rm_flags & RNF_NORMAL) { 730 mmask = m->rm_leaf->rn_mask; 731 if (tt->rn_flags & RNF_NORMAL) { 732 log(LOG_ERR, "Non-unique normal route," 733 " mask not entered\n"); 734 return tt; 735 } 736 } else 737 mmask = m->rm_mask; 738 if (mmask == netmask) { 739 m->rm_refs++; 740 tt->rn_mklist = m; 741 return tt; 742 } 743 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 744 break; 745 } 746 *mp = rn_new_radix_mask(tt, *mp); 747 return tt; 748 } 749 750 struct radix_node * 751 rn_delete1( 752 const void *v_arg, 753 const void *netmask_arg, 754 struct radix_node_head *head, 755 struct radix_node *rn) 756 { 757 struct radix_node *t, *p, *x, *tt; 758 struct radix_mask *m, *saved_m, **mp; 759 struct radix_node *dupedkey, *saved_tt, *top; 760 const char *v, *netmask; 761 int b, head_off, vlen; 762 763 v = v_arg; 764 netmask = netmask_arg; 765 x = head->rnh_treetop; 766 tt = rn_search(v, x); 767 head_off = x->rn_off; 768 vlen = *(const u_char *)v; 769 saved_tt = tt; 770 top = x; 771 if (tt == NULL || 772 memcmp(v + head_off, tt->rn_key + head_off, vlen - head_off) != 0) 773 return NULL; 774 /* 775 * Delete our route from mask lists. 776 */ 777 if (netmask != NULL) { 778 if ((x = rn_addmask(netmask, 1, head_off)) == NULL) 779 return NULL; 780 netmask = x->rn_key; 781 while (tt->rn_mask != netmask) 782 if ((tt = tt->rn_dupedkey) == NULL) 783 return NULL; 784 } 785 if (tt->rn_mask == NULL || (saved_m = m = tt->rn_mklist) == NULL) 786 goto on1; 787 if (tt->rn_flags & RNF_NORMAL) { 788 if (m->rm_leaf != tt || m->rm_refs > 0) { 789 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 790 return NULL; /* dangling ref could cause disaster */ 791 } 792 } else { 793 if (m->rm_mask != tt->rn_mask) { 794 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 795 goto on1; 796 } 797 if (--m->rm_refs >= 0) 798 goto on1; 799 } 800 b = -1 - tt->rn_b; 801 t = saved_tt->rn_p; 802 if (b > t->rn_b) 803 goto on1; /* Wasn't lifted at all */ 804 do { 805 x = t; 806 t = t->rn_p; 807 } while (b <= t->rn_b && x != top); 808 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { 809 if (m == saved_m) { 810 *mp = m->rm_mklist; 811 MKFree(m); 812 break; 813 } 814 } 815 if (m == NULL) { 816 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 817 if (tt->rn_flags & RNF_NORMAL) 818 return NULL; /* Dangling ref to us */ 819 } 820 on1: 821 /* 822 * Eliminate us from tree 823 */ 824 if (tt->rn_flags & RNF_ROOT) 825 return NULL; 826 #ifdef RN_DEBUG 827 if (rn_debug) 828 log(LOG_DEBUG, "%s: Going In:\n", __func__), traverse(head, tt); 829 #endif 830 t = tt->rn_p; 831 dupedkey = saved_tt->rn_dupedkey; 832 if (dupedkey != NULL) { 833 /* 834 * Here, tt is the deletion target, and 835 * saved_tt is the head of the dupedkey chain. 836 */ 837 if (tt == saved_tt) { 838 x = dupedkey; 839 x->rn_p = t; 840 if (t->rn_l == tt) 841 t->rn_l = x; 842 else 843 t->rn_r = x; 844 } else { 845 /* find node in front of tt on the chain */ 846 for (x = p = saved_tt; 847 p != NULL && p->rn_dupedkey != tt;) 848 p = p->rn_dupedkey; 849 if (p != NULL) { 850 p->rn_dupedkey = tt->rn_dupedkey; 851 if (tt->rn_dupedkey != NULL) 852 tt->rn_dupedkey->rn_p = p; 853 } else 854 log(LOG_ERR, "rn_delete: couldn't find us\n"); 855 } 856 t = tt + 1; 857 if (t->rn_flags & RNF_ACTIVE) { 858 *++x = *t; 859 p = t->rn_p; 860 if (p->rn_l == t) 861 p->rn_l = x; 862 else 863 p->rn_r = x; 864 x->rn_l->rn_p = x; 865 x->rn_r->rn_p = x; 866 } 867 goto out; 868 } 869 if (t->rn_l == tt) 870 x = t->rn_r; 871 else 872 x = t->rn_l; 873 p = t->rn_p; 874 if (p->rn_r == t) 875 p->rn_r = x; 876 else 877 p->rn_l = x; 878 x->rn_p = p; 879 /* 880 * Demote routes attached to us. 881 */ 882 if (t->rn_mklist == NULL) 883 ; 884 else if (x->rn_b >= 0) { 885 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 886 ; 887 *mp = t->rn_mklist; 888 } else { 889 /* If there are any key,mask pairs in a sibling 890 duped-key chain, some subset will appear sorted 891 in the same order attached to our mklist */ 892 for (m = t->rn_mklist; 893 m != NULL && x != NULL; 894 x = x->rn_dupedkey) { 895 if (m == x->rn_mklist) { 896 struct radix_mask *mm = m->rm_mklist; 897 x->rn_mklist = NULL; 898 if (--(m->rm_refs) < 0) 899 MKFree(m); 900 m = mm; 901 } 902 } 903 if (m != NULL) { 904 log(LOG_ERR, "rn_delete: Orphaned Mask %p at %p\n", 905 m, x); 906 } 907 } 908 /* 909 * We may be holding an active internal node in the tree. 910 */ 911 x = tt + 1; 912 if (t != x) { 913 *t = *x; 914 t->rn_l->rn_p = t; 915 t->rn_r->rn_p = t; 916 p = x->rn_p; 917 if (p->rn_l == x) 918 p->rn_l = t; 919 else 920 p->rn_r = t; 921 } 922 out: 923 #ifdef RN_DEBUG 924 if (rn_debug) { 925 log(LOG_DEBUG, "%s: Coming Out:\n", __func__), 926 traverse(head, tt); 927 } 928 #endif /* RN_DEBUG */ 929 tt->rn_flags &= ~RNF_ACTIVE; 930 tt[1].rn_flags &= ~RNF_ACTIVE; 931 return tt; 932 } 933 934 struct radix_node * 935 rn_delete( 936 const void *v_arg, 937 const void *netmask_arg, 938 struct radix_node_head *head) 939 { 940 return rn_delete1(v_arg, netmask_arg, head, NULL); 941 } 942 943 static struct radix_node * 944 rn_walknext(struct radix_node *rn, rn_printer_t printer, void *arg) 945 { 946 /* If at right child go back up, otherwise, go right */ 947 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) { 948 if (printer != NULL) 949 (*printer)(arg, SUBTREE_CLOSE); 950 rn = rn->rn_p; 951 } 952 if (printer) 953 rn_nodeprint(rn->rn_p, printer, arg, ""); 954 /* Find the next *leaf* since next node might vanish, too */ 955 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) { 956 if (printer != NULL) 957 (*printer)(arg, SUBTREE_OPEN); 958 rn = rn->rn_l; 959 } 960 return rn; 961 } 962 963 static struct radix_node * 964 rn_walkfirst(struct radix_node *rn, rn_printer_t printer, void *arg) 965 { 966 /* First time through node, go left */ 967 while (rn->rn_b >= 0) { 968 if (printer != NULL) 969 (*printer)(arg, SUBTREE_OPEN); 970 rn = rn->rn_l; 971 } 972 return rn; 973 } 974 975 int 976 rn_walktree( 977 struct radix_node_head *h, 978 int (*f)(struct radix_node *, void *), 979 void *w) 980 { 981 int error; 982 struct radix_node *base, *next, *rn; 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 rn = rn_walkfirst(h->rnh_treetop, NULL, NULL); 989 for (;;) { 990 base = rn; 991 next = rn_walknext(rn, NULL, NULL); 992 /* Process leaves */ 993 while ((rn = base) != NULL) { 994 base = rn->rn_dupedkey; 995 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 996 return error; 997 } 998 rn = next; 999 if (rn->rn_flags & RNF_ROOT) 1000 return 0; 1001 } 1002 /* NOTREACHED */ 1003 } 1004 1005 int 1006 rn_inithead(head, off) 1007 void **head; 1008 int off; 1009 { 1010 struct radix_node_head *rnh; 1011 1012 if (*head != NULL) 1013 return 1; 1014 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 1015 if (rnh == NULL) 1016 return 0; 1017 *head = rnh; 1018 return rn_inithead0(rnh, off); 1019 } 1020 1021 int 1022 rn_inithead0(rnh, off) 1023 struct radix_node_head *rnh; 1024 int off; 1025 { 1026 struct radix_node *t; 1027 struct radix_node *tt; 1028 struct radix_node *ttt; 1029 1030 memset(rnh, 0, sizeof(*rnh)); 1031 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 1032 ttt = rnh->rnh_nodes + 2; 1033 t->rn_r = ttt; 1034 t->rn_p = t; 1035 tt = t->rn_l; 1036 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 1037 tt->rn_b = -1 - off; 1038 *ttt = *tt; 1039 ttt->rn_key = rn_ones; 1040 rnh->rnh_addaddr = rn_addroute; 1041 rnh->rnh_deladdr = rn_delete; 1042 rnh->rnh_matchaddr = rn_match; 1043 rnh->rnh_lookup = rn_lookup; 1044 rnh->rnh_treetop = t; 1045 return 1; 1046 } 1047 1048 void 1049 rn_init() 1050 { 1051 char *cp, *cplim; 1052 #ifdef _KERNEL 1053 static int initialized; 1054 __link_set_decl(domains, struct domain); 1055 struct domain *const *dpp; 1056 1057 if (initialized) 1058 return; 1059 initialized = 1; 1060 1061 __link_set_foreach(dpp, domains) { 1062 if ((*dpp)->dom_maxrtkey > max_keylen) 1063 max_keylen = (*dpp)->dom_maxrtkey; 1064 } 1065 #endif 1066 if (max_keylen == 0) { 1067 log(LOG_ERR, 1068 "rn_init: radix functions require max_keylen be set\n"); 1069 return; 1070 } 1071 R_Malloc(rn_zeros, char *, 3 * max_keylen); 1072 if (rn_zeros == NULL) 1073 panic("rn_init"); 1074 memset(rn_zeros, 0, 3 * max_keylen); 1075 rn_ones = cp = rn_zeros + max_keylen; 1076 addmask_key = cplim = rn_ones + max_keylen; 1077 while (cp < cplim) 1078 *cp++ = -1; 1079 if (rn_inithead((void *)&mask_rnhead, 0) == 0) 1080 panic("rn_init 2"); 1081 } 1082