1 /* $NetBSD: radix.c,v 1.11 1996/03/16 23:55:36 christos 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)radix.c 8.4 (Berkeley) 11/2/94 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 #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 53 int max_keylen; 54 struct radix_mask *rn_mkfreelist; 55 struct radix_node_head *mask_rnhead; 56 static char *addmask_key; 57 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 58 static char *rn_zeros, *rn_ones; 59 60 #define rn_masktop (mask_rnhead->rnh_treetop) 61 #undef Bcmp 62 #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 63 64 65 static int rn_satsifies_leaf __P((char *, struct radix_node *, int)); 66 static int rn_lexobetter __P((void *, void *)); 67 static struct radix_mask *rn_new_radix_mask __P((struct radix_node *, 68 struct radix_mask *)); 69 /* 70 * The data structure for the keys is a radix tree with one way 71 * branching removed. The index rn_b at an internal node n represents a bit 72 * position to be tested. The tree is arranged so that all descendants 73 * of a node n have keys whose bits all agree up to position rn_b - 1. 74 * (We say the index of n is rn_b.) 75 * 76 * There is at least one descendant which has a one bit at position rn_b, 77 * and at least one with a zero there. 78 * 79 * A route is determined by a pair of key and mask. We require that the 80 * bit-wise logical and of the key and mask to be the key. 81 * We define the index of a route to associated with the mask to be 82 * the first bit number in the mask where 0 occurs (with bit number 0 83 * representing the highest order bit). 84 * 85 * We say a mask is normal if every bit is 0, past the index of the mask. 86 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 87 * and m is a normal mask, then the route applies to every descendant of n. 88 * If the index(m) < rn_b, this implies the trailing last few bits of k 89 * before bit b are all 0, (and hence consequently true of every descendant 90 * of n), so the route applies to all descendants of the node as well. 91 * 92 * Similar logic shows that a non-normal mask m such that 93 * index(m) <= index(n) could potentially apply to many children of n. 94 * Thus, for each non-host route, we attach its mask to a list at an internal 95 * node as high in the tree as we can go. 96 * 97 * The present version of the code makes use of normal routes in short- 98 * circuiting an explict mask and compare operation when testing whether 99 * a key satisfies a normal route, and also in remembering the unique leaf 100 * that governs a subtree. 101 */ 102 103 struct radix_node * 104 rn_search(v_arg, head) 105 void *v_arg; 106 struct radix_node *head; 107 { 108 register struct radix_node *x; 109 register caddr_t v; 110 111 for (x = head, v = v_arg; x->rn_b >= 0;) { 112 if (x->rn_bmask & v[x->rn_off]) 113 x = x->rn_r; 114 else 115 x = x->rn_l; 116 } 117 return (x); 118 }; 119 120 struct radix_node * 121 rn_search_m(v_arg, head, m_arg) 122 struct radix_node *head; 123 void *v_arg, *m_arg; 124 { 125 register struct radix_node *x; 126 register caddr_t v = v_arg, m = m_arg; 127 128 for (x = head; x->rn_b >= 0;) { 129 if ((x->rn_bmask & m[x->rn_off]) && 130 (x->rn_bmask & v[x->rn_off])) 131 x = x->rn_r; 132 else 133 x = x->rn_l; 134 } 135 return x; 136 }; 137 138 int 139 rn_refines(m_arg, n_arg) 140 void *m_arg, *n_arg; 141 { 142 register caddr_t m = m_arg, n = n_arg; 143 register caddr_t lim, lim2 = lim = n + *(u_char *)n; 144 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 145 int masks_are_equal = 1; 146 147 if (longer > 0) 148 lim -= longer; 149 while (n < lim) { 150 if (*n & ~(*m)) 151 return 0; 152 if (*n++ != *m++) 153 masks_are_equal = 0; 154 } 155 while (n < lim2) 156 if (*n++) 157 return 0; 158 if (masks_are_equal && (longer < 0)) 159 for (lim2 = m - longer; m < lim2; ) 160 if (*m++) 161 return 1; 162 return (!masks_are_equal); 163 } 164 165 struct radix_node * 166 rn_lookup(v_arg, m_arg, head) 167 void *v_arg, *m_arg; 168 struct radix_node_head *head; 169 { 170 register struct radix_node *x; 171 caddr_t netmask = 0; 172 173 if (m_arg) { 174 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 175 return (0); 176 netmask = x->rn_key; 177 } 178 x = rn_match(v_arg, head); 179 if (x && netmask) { 180 while (x && x->rn_mask != netmask) 181 x = x->rn_dupedkey; 182 } 183 return x; 184 } 185 186 static int 187 rn_satsifies_leaf(trial, leaf, skip) 188 char *trial; 189 register struct radix_node *leaf; 190 int skip; 191 { 192 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 193 char *cplim; 194 int length = min(*(u_char *)cp, *(u_char *)cp2); 195 196 if (cp3 == 0) 197 cp3 = rn_ones; 198 else 199 length = min(length, *(u_char *)cp3); 200 cplim = cp + length; cp3 += skip; cp2 += skip; 201 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 202 if ((*cp ^ *cp2) & *cp3) 203 return 0; 204 return 1; 205 } 206 207 struct radix_node * 208 rn_match(v_arg, head) 209 void *v_arg; 210 struct radix_node_head *head; 211 { 212 caddr_t v = v_arg; 213 register struct radix_node *t = head->rnh_treetop, *x; 214 register caddr_t cp = v, cp2; 215 caddr_t cplim; 216 struct radix_node *saved_t, *top = t; 217 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 218 register int test, b, rn_b; 219 220 /* 221 * Open code rn_search(v, top) to avoid overhead of extra 222 * subroutine call. 223 */ 224 for (; t->rn_b >= 0; ) { 225 if (t->rn_bmask & cp[t->rn_off]) 226 t = t->rn_r; 227 else 228 t = t->rn_l; 229 } 230 /* 231 * See if we match exactly as a host destination 232 * or at least learn how many bits match, for normal mask finesse. 233 * 234 * It doesn't hurt us to limit how many bytes to check 235 * to the length of the mask, since if it matches we had a genuine 236 * match and the leaf we have is the most specific one anyway; 237 * if it didn't match with a shorter length it would fail 238 * with a long one. This wins big for class B&C netmasks which 239 * are probably the most common case... 240 */ 241 if (t->rn_mask) 242 vlen = *(u_char *)t->rn_mask; 243 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 244 for (; cp < cplim; cp++, cp2++) 245 if (*cp != *cp2) 246 goto on1; 247 /* 248 * This extra grot is in case we are explicitly asked 249 * to look up the default. Ugh! 250 */ 251 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 252 t = t->rn_dupedkey; 253 return t; 254 on1: 255 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 256 for (b = 7; (test >>= 1) > 0;) 257 b--; 258 matched_off = cp - v; 259 b += matched_off << 3; 260 rn_b = -1 - b; 261 /* 262 * If there is a host route in a duped-key chain, it will be first. 263 */ 264 if ((saved_t = t)->rn_mask == 0) 265 t = t->rn_dupedkey; 266 for (; t; t = t->rn_dupedkey) 267 /* 268 * Even if we don't match exactly as a host, 269 * we may match if the leaf we wound up at is 270 * a route to a net. 271 */ 272 if (t->rn_flags & RNF_NORMAL) { 273 if (rn_b <= t->rn_b) 274 return t; 275 } else if (rn_satsifies_leaf(v, t, matched_off)) 276 return t; 277 t = saved_t; 278 /* start searching up the tree */ 279 do { 280 register struct radix_mask *m; 281 t = t->rn_p; 282 if ((m = t->rn_mklist) != NULL) { 283 /* 284 * If non-contiguous masks ever become important 285 * we can restore the masking and open coding of 286 * the search and satisfaction test and put the 287 * calculation of "off" back before the "do". 288 */ 289 do { 290 if (m->rm_flags & RNF_NORMAL) { 291 if (rn_b <= m->rm_b) 292 return (m->rm_leaf); 293 } else { 294 off = min(t->rn_off, matched_off); 295 x = rn_search_m(v, t, m->rm_mask); 296 while (x && x->rn_mask != m->rm_mask) 297 x = x->rn_dupedkey; 298 if (x && rn_satsifies_leaf(v, x, off)) 299 return x; 300 } 301 } while ((m = m->rm_mklist) != NULL); 302 } 303 } while (t != top); 304 return 0; 305 }; 306 307 #ifdef RN_DEBUG 308 int rn_nodenum; 309 struct radix_node *rn_clist; 310 int rn_saveinfo; 311 int rn_debug = 1; 312 #endif 313 314 struct radix_node * 315 rn_newpair(v, b, nodes) 316 void *v; 317 int b; 318 struct radix_node nodes[2]; 319 { 320 register struct radix_node *tt = nodes, *t = tt + 1; 321 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 322 t->rn_l = tt; t->rn_off = b >> 3; 323 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 324 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 325 #ifdef RN_DEBUG 326 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 327 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 328 #endif 329 return t; 330 } 331 332 struct radix_node * 333 rn_insert(v_arg, head, dupentry, nodes) 334 void *v_arg; 335 struct radix_node_head *head; 336 int *dupentry; 337 struct radix_node nodes[2]; 338 { 339 caddr_t v = v_arg; 340 struct radix_node *top = head->rnh_treetop; 341 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 342 register struct radix_node *t = rn_search(v_arg, top); 343 register caddr_t cp = v + head_off; 344 register int b; 345 struct radix_node *tt; 346 /* 347 * Find first bit at which v and t->rn_key differ 348 */ 349 { 350 register caddr_t cp2 = t->rn_key + head_off; 351 register int cmp_res; 352 caddr_t cplim = v + vlen; 353 354 while (cp < cplim) 355 if (*cp2++ != *cp++) 356 goto on1; 357 *dupentry = 1; 358 return t; 359 on1: 360 *dupentry = 0; 361 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 362 for (b = (cp - v) << 3; cmp_res; b--) 363 cmp_res >>= 1; 364 } 365 { 366 register struct radix_node *p, *x = top; 367 cp = v; 368 do { 369 p = x; 370 if (cp[x->rn_off] & x->rn_bmask) 371 x = x->rn_r; 372 else x = x->rn_l; 373 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 374 #ifdef RN_DEBUG 375 if (rn_debug) 376 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 377 #endif 378 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 379 if ((cp[p->rn_off] & p->rn_bmask) == 0) 380 p->rn_l = t; 381 else 382 p->rn_r = t; 383 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 384 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 385 t->rn_r = x; 386 } else { 387 t->rn_r = tt; t->rn_l = x; 388 } 389 #ifdef RN_DEBUG 390 if (rn_debug) 391 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 392 #endif 393 } 394 return (tt); 395 } 396 397 struct radix_node * 398 rn_addmask(n_arg, search, skip) 399 int search, skip; 400 void *n_arg; 401 { 402 caddr_t netmask = (caddr_t)n_arg; 403 register struct radix_node *x; 404 register caddr_t cp, cplim; 405 register int b = 0, mlen, j; 406 int maskduplicated, m0, isnormal; 407 struct radix_node *saved_x; 408 static int last_zeroed = 0; 409 410 if ((mlen = *(u_char *)netmask) > max_keylen) 411 mlen = max_keylen; 412 if (skip == 0) 413 skip = 1; 414 if (mlen <= skip) 415 return (mask_rnhead->rnh_nodes); 416 if (skip > 1) 417 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 418 if ((m0 = mlen) > skip) 419 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 420 /* 421 * Trim trailing zeroes. 422 */ 423 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 424 cp--; 425 mlen = cp - addmask_key; 426 if (mlen <= skip) { 427 if (m0 >= last_zeroed) 428 last_zeroed = mlen; 429 return (mask_rnhead->rnh_nodes); 430 } 431 if (m0 < last_zeroed) 432 Bzero(addmask_key + m0, last_zeroed - m0); 433 *addmask_key = last_zeroed = mlen; 434 x = rn_search(addmask_key, rn_masktop); 435 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 436 x = 0; 437 if (x || search) 438 return (x); 439 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 440 if ((saved_x = x) == 0) 441 return (0); 442 Bzero(x, max_keylen + 2 * sizeof (*x)); 443 netmask = cp = (caddr_t)(x + 2); 444 Bcopy(addmask_key, cp, mlen); 445 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 446 if (maskduplicated) { 447 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 448 Free(saved_x); 449 return (x); 450 } 451 /* 452 * Calculate index of mask, and check for normalcy. 453 */ 454 cplim = netmask + mlen; isnormal = 1; 455 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 456 cp++; 457 if (cp != cplim) { 458 for (j = 0x80; (j & *cp) != 0; j >>= 1) 459 b++; 460 if (*cp != normal_chars[b] || cp != (cplim - 1)) 461 isnormal = 0; 462 } 463 b += (cp - netmask) << 3; 464 x->rn_b = -1 - b; 465 if (isnormal) 466 x->rn_flags |= RNF_NORMAL; 467 return (x); 468 } 469 470 static int /* XXX: arbitrary ordering for non-contiguous masks */ 471 rn_lexobetter(m_arg, n_arg) 472 void *m_arg, *n_arg; 473 { 474 register u_char *mp = m_arg, *np = n_arg, *lim; 475 476 if (*mp > *np) 477 return 1; /* not really, but need to check longer one first */ 478 if (*mp == *np) 479 for (lim = mp + *mp; mp < lim;) 480 if (*mp++ > *np++) 481 return 1; 482 return 0; 483 } 484 485 static struct radix_mask * 486 rn_new_radix_mask(tt, next) 487 register struct radix_node *tt; 488 register struct radix_mask *next; 489 { 490 register struct radix_mask *m; 491 492 MKGet(m); 493 if (m == 0) { 494 log(LOG_ERR, "Mask for route not entered\n"); 495 return (0); 496 } 497 Bzero(m, sizeof *m); 498 m->rm_b = tt->rn_b; 499 m->rm_flags = tt->rn_flags; 500 if (tt->rn_flags & RNF_NORMAL) 501 m->rm_leaf = tt; 502 else 503 m->rm_mask = tt->rn_mask; 504 m->rm_mklist = next; 505 tt->rn_mklist = m; 506 return m; 507 } 508 509 struct radix_node * 510 rn_addroute(v_arg, n_arg, head, treenodes) 511 void *v_arg, *n_arg; 512 struct radix_node_head *head; 513 struct radix_node treenodes[2]; 514 { 515 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 516 register struct radix_node *t, *x = NULL, *tt; 517 struct radix_node *saved_tt, *top = head->rnh_treetop; 518 short b = 0, b_leaf = 0; 519 int keyduplicated; 520 caddr_t mmask; 521 struct radix_mask *m, **mp; 522 523 /* 524 * In dealing with non-contiguous masks, there may be 525 * many different routes which have the same mask. 526 * We will find it useful to have a unique pointer to 527 * the mask to speed avoiding duplicate references at 528 * nodes and possibly save time in calculating indices. 529 */ 530 if (netmask) { 531 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 532 return (0); 533 b_leaf = x->rn_b; 534 b = -1 - x->rn_b; 535 netmask = x->rn_key; 536 } 537 /* 538 * Deal with duplicated keys: attach node to previous instance 539 */ 540 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 541 if (keyduplicated) { 542 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 543 if (tt->rn_mask == netmask) 544 return (0); 545 if (netmask == 0 || 546 (tt->rn_mask && 547 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 548 rn_refines(netmask, tt->rn_mask) || 549 rn_lexobetter(netmask, tt->rn_mask)))) 550 break; 551 } 552 /* 553 * If the mask is not duplicated, we wouldn't 554 * find it among possible duplicate key entries 555 * anyway, so the above test doesn't hurt. 556 * 557 * We sort the masks for a duplicated key the same way as 558 * in a masklist -- most specific to least specific. 559 * This may require the unfortunate nuisance of relocating 560 * the head of the list. 561 */ 562 if (tt == saved_tt) { 563 struct radix_node *xx = x; 564 /* link in at head of list */ 565 (tt = treenodes)->rn_dupedkey = t; 566 tt->rn_flags = t->rn_flags; 567 tt->rn_p = x = t->rn_p; 568 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 569 saved_tt = tt; x = xx; 570 } else { 571 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 572 t->rn_dupedkey = tt; 573 } 574 #ifdef RN_DEBUG 575 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 576 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 577 #endif 578 tt->rn_key = (caddr_t) v; 579 tt->rn_b = -1; 580 tt->rn_flags = RNF_ACTIVE; 581 } 582 /* 583 * Put mask in tree. 584 */ 585 if (netmask) { 586 tt->rn_mask = netmask; 587 tt->rn_b = x->rn_b; 588 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 589 } 590 t = saved_tt->rn_p; 591 if (keyduplicated) 592 goto on2; 593 b_leaf = -1 - t->rn_b; 594 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 595 /* Promote general routes from below */ 596 if (x->rn_b < 0) { 597 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 598 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 599 *mp = m = rn_new_radix_mask(x, 0); 600 if (m) 601 mp = &m->rm_mklist; 602 } 603 } else if (x->rn_mklist) { 604 /* 605 * Skip over masks whose index is > that of new node 606 */ 607 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 608 if (m->rm_b >= b_leaf) 609 break; 610 t->rn_mklist = m; *mp = 0; 611 } 612 on2: 613 /* Add new route to highest possible ancestor's list */ 614 if ((netmask == 0) || (b > t->rn_b )) 615 return tt; /* can't lift at all */ 616 b_leaf = tt->rn_b; 617 do { 618 x = t; 619 t = t->rn_p; 620 } while (b <= t->rn_b && x != top); 621 /* 622 * Search through routes associated with node to 623 * insert new route according to index. 624 * Need same criteria as when sorting dupedkeys to avoid 625 * double loop on deletion. 626 */ 627 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { 628 if (m->rm_b < b_leaf) 629 continue; 630 if (m->rm_b > b_leaf) 631 break; 632 if (m->rm_flags & RNF_NORMAL) { 633 mmask = m->rm_leaf->rn_mask; 634 if (tt->rn_flags & RNF_NORMAL) { 635 log(LOG_ERR, 636 "Non-unique normal route, mask not entered"); 637 return tt; 638 } 639 } else 640 mmask = m->rm_mask; 641 if (mmask == netmask) { 642 m->rm_refs++; 643 tt->rn_mklist = m; 644 return tt; 645 } 646 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 647 break; 648 } 649 *mp = rn_new_radix_mask(tt, *mp); 650 return tt; 651 } 652 653 struct radix_node * 654 rn_delete(v_arg, netmask_arg, head) 655 void *v_arg, *netmask_arg; 656 struct radix_node_head *head; 657 { 658 register struct radix_node *t, *p, *x, *tt; 659 struct radix_mask *m, *saved_m, **mp; 660 struct radix_node *dupedkey, *saved_tt, *top; 661 caddr_t v, netmask; 662 int b, head_off, vlen; 663 664 v = v_arg; 665 netmask = netmask_arg; 666 x = head->rnh_treetop; 667 tt = rn_search(v, x); 668 head_off = x->rn_off; 669 vlen = *(u_char *)v; 670 saved_tt = tt; 671 top = x; 672 if (tt == 0 || 673 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 674 return (0); 675 /* 676 * Delete our route from mask lists. 677 */ 678 if (netmask) { 679 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 680 return (0); 681 netmask = x->rn_key; 682 while (tt->rn_mask != netmask) 683 if ((tt = tt->rn_dupedkey) == 0) 684 return (0); 685 } 686 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 687 goto on1; 688 if (tt->rn_flags & RNF_NORMAL) { 689 if (m->rm_leaf != tt || m->rm_refs > 0) { 690 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 691 return 0; /* dangling ref could cause disaster */ 692 } 693 } else { 694 if (m->rm_mask != tt->rn_mask) { 695 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 696 goto on1; 697 } 698 if (--m->rm_refs >= 0) 699 goto on1; 700 } 701 b = -1 - tt->rn_b; 702 t = saved_tt->rn_p; 703 if (b > t->rn_b) 704 goto on1; /* Wasn't lifted at all */ 705 do { 706 x = t; 707 t = t->rn_p; 708 } while (b <= t->rn_b && x != top); 709 for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) 710 if (m == saved_m) { 711 *mp = m->rm_mklist; 712 MKFree(m); 713 break; 714 } 715 if (m == 0) { 716 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 717 if (tt->rn_flags & RNF_NORMAL) 718 return (0); /* Dangling ref to us */ 719 } 720 on1: 721 /* 722 * Eliminate us from tree 723 */ 724 if (tt->rn_flags & RNF_ROOT) 725 return (0); 726 #ifdef RN_DEBUG 727 /* Get us out of the creation list */ 728 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 729 if (t) t->rn_ybro = tt->rn_ybro; 730 #endif 731 t = tt->rn_p; 732 if ((dupedkey = saved_tt->rn_dupedkey) != 0) { 733 if (tt == saved_tt) { 734 x = dupedkey; x->rn_p = t; 735 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 736 } else { 737 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 738 p = p->rn_dupedkey; 739 if (p) p->rn_dupedkey = tt->rn_dupedkey; 740 else log(LOG_ERR, "rn_delete: couldn't find us\n"); 741 } 742 t = tt + 1; 743 if (t->rn_flags & RNF_ACTIVE) { 744 #ifndef RN_DEBUG 745 *++x = *t; p = t->rn_p; 746 #else 747 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 748 #endif 749 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 750 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 751 } 752 goto out; 753 } 754 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 755 p = t->rn_p; 756 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 757 x->rn_p = p; 758 /* 759 * Demote routes attached to us. 760 */ 761 if (t->rn_mklist) { 762 if (x->rn_b >= 0) { 763 for (mp = &x->rn_mklist; (m = *mp) != NULL;) 764 mp = &m->rm_mklist; 765 *mp = t->rn_mklist; 766 } else { 767 /* If there are any key,mask pairs in a sibling 768 duped-key chain, some subset will appear sorted 769 in the same order attached to our mklist */ 770 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 771 if (m == x->rn_mklist) { 772 struct radix_mask *mm = m->rm_mklist; 773 x->rn_mklist = 0; 774 if (--(m->rm_refs) < 0) 775 MKFree(m); 776 m = mm; 777 } 778 if (m) 779 log(LOG_ERR, "%s %p at %p\n", 780 "rn_delete: Orphaned Mask", m, x); 781 } 782 } 783 /* 784 * We may be holding an active internal node in the tree. 785 */ 786 x = tt + 1; 787 if (t != x) { 788 #ifndef RN_DEBUG 789 *t = *x; 790 #else 791 b = t->rn_info; *t = *x; t->rn_info = b; 792 #endif 793 t->rn_l->rn_p = t; t->rn_r->rn_p = t; 794 p = x->rn_p; 795 if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; 796 } 797 out: 798 tt->rn_flags &= ~RNF_ACTIVE; 799 tt[1].rn_flags &= ~RNF_ACTIVE; 800 return (tt); 801 } 802 803 int 804 rn_walktree(h, f, w) 805 struct radix_node_head *h; 806 register int (*f) __P((struct radix_node *, void *)); 807 void *w; 808 { 809 int error; 810 struct radix_node *base, *next; 811 register struct radix_node *rn = h->rnh_treetop; 812 /* 813 * This gets complicated because we may delete the node 814 * while applying the function f to it, so we need to calculate 815 * the successor node in advance. 816 */ 817 /* First time through node, go left */ 818 while (rn->rn_b >= 0) 819 rn = rn->rn_l; 820 for (;;) { 821 base = rn; 822 /* If at right child go back up, otherwise, go right */ 823 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 824 rn = rn->rn_p; 825 /* Find the next *leaf* since next node might vanish, too */ 826 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 827 rn = rn->rn_l; 828 next = rn; 829 /* Process leaves */ 830 while ((rn = base) != NULL) { 831 base = rn->rn_dupedkey; 832 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 833 return (error); 834 } 835 rn = next; 836 if (rn->rn_flags & RNF_ROOT) 837 return (0); 838 } 839 /* NOTREACHED */ 840 } 841 842 int 843 rn_inithead(head, off) 844 void **head; 845 int off; 846 { 847 register struct radix_node_head *rnh; 848 register struct radix_node *t, *tt, *ttt; 849 if (*head) 850 return (1); 851 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 852 if (rnh == 0) 853 return (0); 854 Bzero(rnh, sizeof (*rnh)); 855 *head = rnh; 856 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 857 ttt = rnh->rnh_nodes + 2; 858 t->rn_r = ttt; 859 t->rn_p = t; 860 tt = t->rn_l; 861 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 862 tt->rn_b = -1 - off; 863 *ttt = *tt; 864 ttt->rn_key = rn_ones; 865 rnh->rnh_addaddr = rn_addroute; 866 rnh->rnh_deladdr = rn_delete; 867 rnh->rnh_matchaddr = rn_match; 868 rnh->rnh_lookup = rn_lookup; 869 rnh->rnh_walktree = rn_walktree; 870 rnh->rnh_treetop = t; 871 return (1); 872 } 873 874 void 875 rn_init() 876 { 877 char *cp, *cplim; 878 #ifdef _KERNEL 879 struct domain *dom; 880 881 for (dom = domains; dom; dom = dom->dom_next) 882 if (dom->dom_maxrtkey > max_keylen) 883 max_keylen = dom->dom_maxrtkey; 884 #endif 885 if (max_keylen == 0) { 886 log(LOG_ERR, 887 "rn_init: radix functions require max_keylen be set\n"); 888 return; 889 } 890 R_Malloc(rn_zeros, char *, 3 * max_keylen); 891 if (rn_zeros == NULL) 892 panic("rn_init"); 893 Bzero(rn_zeros, 3 * max_keylen); 894 rn_ones = cp = rn_zeros + max_keylen; 895 addmask_key = cplim = rn_ones + max_keylen; 896 while (cp < cplim) 897 *cp++ = -1; 898 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 899 panic("rn_init 2"); 900 } 901