1 /* 2 * Copyright (c) 1988, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)radix.c 8.5 (Berkeley) 05/19/95 8 */ 9 10 /* 11 * Routines to build and maintain radix trees for routing lookups. 12 */ 13 #ifndef _RADIX_H_ 14 #include <sys/param.h> 15 #ifdef KERNEL 16 #include <sys/systm.h> 17 #include <sys/malloc.h> 18 #define M_DONTWAIT M_NOWAIT 19 #include <sys/domain.h> 20 #else 21 #include <stdlib.h> 22 #endif 23 #include <sys/syslog.h> 24 #include <net/radix.h> 25 #endif 26 27 int max_keylen; 28 struct radix_mask *rn_mkfreelist; 29 struct radix_node_head *mask_rnhead; 30 static char *addmask_key; 31 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; 32 static char *rn_zeros, *rn_ones; 33 34 #define rn_masktop (mask_rnhead->rnh_treetop) 35 #undef Bcmp 36 #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) 37 /* 38 * The data structure for the keys is a radix tree with one way 39 * branching removed. The index rn_b at an internal node n represents a bit 40 * position to be tested. The tree is arranged so that all descendants 41 * of a node n have keys whose bits all agree up to position rn_b - 1. 42 * (We say the index of n is rn_b.) 43 * 44 * There is at least one descendant which has a one bit at position rn_b, 45 * and at least one with a zero there. 46 * 47 * A route is determined by a pair of key and mask. We require that the 48 * bit-wise logical and of the key and mask to be the key. 49 * We define the index of a route to associated with the mask to be 50 * the first bit number in the mask where 0 occurs (with bit number 0 51 * representing the highest order bit). 52 * 53 * We say a mask is normal if every bit is 0, past the index of the mask. 54 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, 55 * and m is a normal mask, then the route applies to every descendant of n. 56 * If the index(m) < rn_b, this implies the trailing last few bits of k 57 * before bit b are all 0, (and hence consequently true of every descendant 58 * of n), so the route applies to all descendants of the node as well. 59 * 60 * Similar logic shows that a non-normal mask m such that 61 * index(m) <= index(n) could potentially apply to many children of n. 62 * Thus, for each non-host route, we attach its mask to a list at an internal 63 * node as high in the tree as we can go. 64 * 65 * The present version of the code makes use of normal routes in short- 66 * circuiting an explict mask and compare operation when testing whether 67 * a key satisfies a normal route, and also in remembering the unique leaf 68 * that governs a subtree. 69 */ 70 71 struct radix_node * 72 rn_search(v_arg, head) 73 void *v_arg; 74 struct radix_node *head; 75 { 76 register struct radix_node *x; 77 register caddr_t v; 78 79 for (x = head, v = v_arg; x->rn_b >= 0;) { 80 if (x->rn_bmask & v[x->rn_off]) 81 x = x->rn_r; 82 else 83 x = x->rn_l; 84 } 85 return (x); 86 }; 87 88 struct radix_node * 89 rn_search_m(v_arg, head, m_arg) 90 struct radix_node *head; 91 void *v_arg, *m_arg; 92 { 93 register struct radix_node *x; 94 register caddr_t v = v_arg, m = m_arg; 95 96 for (x = head; x->rn_b >= 0;) { 97 if ((x->rn_bmask & m[x->rn_off]) && 98 (x->rn_bmask & v[x->rn_off])) 99 x = x->rn_r; 100 else 101 x = x->rn_l; 102 } 103 return x; 104 }; 105 106 int 107 rn_refines(m_arg, n_arg) 108 void *m_arg, *n_arg; 109 { 110 register caddr_t m = m_arg, n = n_arg; 111 register caddr_t lim, lim2 = lim = n + *(u_char *)n; 112 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); 113 int masks_are_equal = 1; 114 115 if (longer > 0) 116 lim -= longer; 117 while (n < lim) { 118 if (*n & ~(*m)) 119 return 0; 120 if (*n++ != *m++) 121 masks_are_equal = 0; 122 } 123 while (n < lim2) 124 if (*n++) 125 return 0; 126 if (masks_are_equal && (longer < 0)) 127 for (lim2 = m - longer; m < lim2; ) 128 if (*m++) 129 return 1; 130 return (!masks_are_equal); 131 } 132 133 struct radix_node * 134 rn_lookup(v_arg, m_arg, head) 135 void *v_arg, *m_arg; 136 struct radix_node_head *head; 137 { 138 register struct radix_node *x; 139 caddr_t netmask = 0; 140 141 if (m_arg) { 142 if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) 143 return (0); 144 netmask = x->rn_key; 145 } 146 x = rn_match(v_arg, head); 147 if (x && netmask) { 148 while (x && x->rn_mask != netmask) 149 x = x->rn_dupedkey; 150 } 151 return x; 152 } 153 154 static int 155 rn_satsifies_leaf(trial, leaf, skip) 156 char *trial; 157 register struct radix_node *leaf; 158 int skip; 159 { 160 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; 161 char *cplim; 162 int length = min(*(u_char *)cp, *(u_char *)cp2); 163 164 if (cp3 == 0) 165 cp3 = rn_ones; 166 else 167 length = min(length, *(u_char *)cp3); 168 cplim = cp + length; cp3 += skip; cp2 += skip; 169 for (cp += skip; cp < cplim; cp++, cp2++, cp3++) 170 if ((*cp ^ *cp2) & *cp3) 171 return 0; 172 return 1; 173 } 174 175 struct radix_node * 176 rn_match(v_arg, head) 177 void *v_arg; 178 struct radix_node_head *head; 179 { 180 caddr_t v = v_arg; 181 register struct radix_node *t = head->rnh_treetop, *x; 182 register caddr_t cp = v, cp2; 183 caddr_t cplim; 184 struct radix_node *saved_t, *top = t; 185 int off = t->rn_off, vlen = *(u_char *)cp, matched_off; 186 register int test, b, rn_b; 187 188 /* 189 * Open code rn_search(v, top) to avoid overhead of extra 190 * subroutine call. 191 */ 192 for (; t->rn_b >= 0; ) { 193 if (t->rn_bmask & cp[t->rn_off]) 194 t = t->rn_r; 195 else 196 t = t->rn_l; 197 } 198 /* 199 * See if we match exactly as a host destination 200 * or at least learn how many bits match, for normal mask finesse. 201 * 202 * It doesn't hurt us to limit how many bytes to check 203 * to the length of the mask, since if it matches we had a genuine 204 * match and the leaf we have is the most specific one anyway; 205 * if it didn't match with a shorter length it would fail 206 * with a long one. This wins big for class B&C netmasks which 207 * are probably the most common case... 208 */ 209 if (t->rn_mask) 210 vlen = *(u_char *)t->rn_mask; 211 cp += off; cp2 = t->rn_key + off; cplim = v + vlen; 212 for (; cp < cplim; cp++, cp2++) 213 if (*cp != *cp2) 214 goto on1; 215 /* 216 * This extra grot is in case we are explicitly asked 217 * to look up the default. Ugh! 218 */ 219 if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) 220 t = t->rn_dupedkey; 221 return t; 222 on1: 223 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ 224 for (b = 7; (test >>= 1) > 0;) 225 b--; 226 matched_off = cp - v; 227 b += matched_off << 3; 228 rn_b = -1 - b; 229 /* 230 * If there is a host route in a duped-key chain, it will be first. 231 */ 232 if ((saved_t = t)->rn_mask == 0) 233 t = t->rn_dupedkey; 234 for (; t; t = t->rn_dupedkey) 235 /* 236 * Even if we don't match exactly as a host, 237 * we may match if the leaf we wound up at is 238 * a route to a net. 239 */ 240 if (t->rn_flags & RNF_NORMAL) { 241 if (rn_b <= t->rn_b) 242 return t; 243 } else if (rn_satsifies_leaf(v, t, matched_off)) 244 return t; 245 t = saved_t; 246 /* start searching up the tree */ 247 do { 248 register struct radix_mask *m; 249 t = t->rn_p; 250 m = t->rn_mklist; 251 if (m) { 252 /* 253 * If non-contiguous masks ever become important 254 * we can restore the masking and open coding of 255 * the search and satisfaction test and put the 256 * calculation of "off" back before the "do". 257 */ 258 do { 259 if (m->rm_flags & RNF_NORMAL) { 260 if (rn_b <= m->rm_b) 261 return (m->rm_leaf); 262 } else { 263 off = min(t->rn_off, matched_off); 264 x = rn_search_m(v, t, m->rm_mask); 265 while (x && x->rn_mask != m->rm_mask) 266 x = x->rn_dupedkey; 267 if (x && rn_satsifies_leaf(v, x, off)) 268 return x; 269 } 270 m = m->rm_mklist; 271 } while (m); 272 } 273 } while (t != top); 274 return 0; 275 }; 276 277 #ifdef RN_DEBUG 278 int rn_nodenum; 279 struct radix_node *rn_clist; 280 int rn_saveinfo; 281 int rn_debug = 1; 282 #endif 283 284 struct radix_node * 285 rn_newpair(v, b, nodes) 286 void *v; 287 int b; 288 struct radix_node nodes[2]; 289 { 290 register struct radix_node *tt = nodes, *t = tt + 1; 291 t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); 292 t->rn_l = tt; t->rn_off = b >> 3; 293 tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; 294 tt->rn_flags = t->rn_flags = RNF_ACTIVE; 295 #ifdef RN_DEBUG 296 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 297 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 298 #endif 299 return t; 300 } 301 302 struct radix_node * 303 rn_insert(v_arg, head, dupentry, nodes) 304 void *v_arg; 305 struct radix_node_head *head; 306 int *dupentry; 307 struct radix_node nodes[2]; 308 { 309 caddr_t v = v_arg; 310 struct radix_node *top = head->rnh_treetop; 311 int head_off = top->rn_off, vlen = (int)*((u_char *)v); 312 register struct radix_node *t = rn_search(v_arg, top); 313 register caddr_t cp = v + head_off; 314 register int b; 315 struct radix_node *tt; 316 /* 317 * Find first bit at which v and t->rn_key differ 318 */ 319 { 320 register caddr_t cp2 = t->rn_key + head_off; 321 register int cmp_res; 322 caddr_t cplim = v + vlen; 323 324 while (cp < cplim) 325 if (*cp2++ != *cp++) 326 goto on1; 327 *dupentry = 1; 328 return t; 329 on1: 330 *dupentry = 0; 331 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; 332 for (b = (cp - v) << 3; cmp_res; b--) 333 cmp_res >>= 1; 334 } 335 { 336 register struct radix_node *p, *x = top; 337 cp = v; 338 do { 339 p = x; 340 if (cp[x->rn_off] & x->rn_bmask) 341 x = x->rn_r; 342 else x = x->rn_l; 343 } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ 344 #ifdef RN_DEBUG 345 if (rn_debug) 346 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); 347 #endif 348 t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; 349 if ((cp[p->rn_off] & p->rn_bmask) == 0) 350 p->rn_l = t; 351 else 352 p->rn_r = t; 353 x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ 354 if ((cp[t->rn_off] & t->rn_bmask) == 0) { 355 t->rn_r = x; 356 } else { 357 t->rn_r = tt; t->rn_l = x; 358 } 359 #ifdef RN_DEBUG 360 if (rn_debug) 361 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); 362 #endif 363 } 364 return (tt); 365 } 366 367 struct radix_node * 368 rn_addmask(n_arg, search, skip) 369 int search, skip; 370 void *n_arg; 371 { 372 caddr_t netmask = (caddr_t)n_arg; 373 register struct radix_node *x; 374 register caddr_t cp, cplim; 375 register int b = 0, mlen, j; 376 int maskduplicated, m0, isnormal; 377 struct radix_node *saved_x; 378 static int last_zeroed = 0; 379 380 if ((mlen = *(u_char *)netmask) > max_keylen) 381 mlen = max_keylen; 382 if (skip == 0) 383 skip = 1; 384 if (mlen <= skip) 385 return (mask_rnhead->rnh_nodes); 386 if (skip > 1) 387 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); 388 if ((m0 = mlen) > skip) 389 Bcopy(netmask + skip, addmask_key + skip, mlen - skip); 390 /* 391 * Trim trailing zeroes. 392 */ 393 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) 394 cp--; 395 mlen = cp - addmask_key; 396 if (mlen <= skip) { 397 if (m0 >= last_zeroed) 398 last_zeroed = mlen; 399 return (mask_rnhead->rnh_nodes); 400 } 401 if (m0 < last_zeroed) 402 Bzero(addmask_key + m0, last_zeroed - m0); 403 *addmask_key = last_zeroed = mlen; 404 x = rn_search(addmask_key, rn_masktop); 405 if (Bcmp(addmask_key, x->rn_key, mlen) != 0) 406 x = 0; 407 if (x || search) 408 return (x); 409 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); 410 if ((saved_x = x) == 0) 411 return (0); 412 Bzero(x, max_keylen + 2 * sizeof (*x)); 413 netmask = cp = (caddr_t)(x + 2); 414 Bcopy(addmask_key, cp, mlen); 415 x = rn_insert(cp, mask_rnhead, &maskduplicated, x); 416 if (maskduplicated) { 417 log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); 418 Free(saved_x); 419 return (x); 420 } 421 /* 422 * Calculate index of mask, and check for normalcy. 423 */ 424 cplim = netmask + mlen; isnormal = 1; 425 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) 426 cp++; 427 if (cp != cplim) { 428 for (j = 0x80; (j & *cp) != 0; j >>= 1) 429 b++; 430 if (*cp != normal_chars[b] || cp != (cplim - 1)) 431 isnormal = 0; 432 } 433 b += (cp - netmask) << 3; 434 x->rn_b = -1 - b; 435 if (isnormal) 436 x->rn_flags |= RNF_NORMAL; 437 return (x); 438 } 439 440 static int /* XXX: arbitrary ordering for non-contiguous masks */ 441 rn_lexobetter(m_arg, n_arg) 442 void *m_arg, *n_arg; 443 { 444 register u_char *mp = m_arg, *np = n_arg, *lim; 445 446 if (*mp > *np) 447 return 1; /* not really, but need to check longer one first */ 448 if (*mp == *np) 449 for (lim = mp + *mp; mp < lim;) 450 if (*mp++ > *np++) 451 return 1; 452 return 0; 453 } 454 455 static struct radix_mask * 456 rn_new_radix_mask(tt, next) 457 register struct radix_node *tt; 458 register struct radix_mask *next; 459 { 460 register struct radix_mask *m; 461 462 MKGet(m); 463 if (m == 0) { 464 log(LOG_ERR, "Mask for route not entered\n"); 465 return (0); 466 } 467 Bzero(m, sizeof *m); 468 m->rm_b = tt->rn_b; 469 m->rm_flags = tt->rn_flags; 470 if (tt->rn_flags & RNF_NORMAL) 471 m->rm_leaf = tt; 472 else 473 m->rm_mask = tt->rn_mask; 474 m->rm_mklist = next; 475 tt->rn_mklist = m; 476 return m; 477 } 478 479 struct radix_node * 480 rn_addroute(v_arg, n_arg, head, treenodes) 481 void *v_arg, *n_arg; 482 struct radix_node_head *head; 483 struct radix_node treenodes[2]; 484 { 485 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; 486 register struct radix_node *t, *x = 0, *tt; 487 struct radix_node *saved_tt, *top = head->rnh_treetop; 488 short b = 0, b_leaf = 0; 489 int keyduplicated; 490 caddr_t mmask; 491 struct radix_mask *m, **mp; 492 493 /* 494 * In dealing with non-contiguous masks, there may be 495 * many different routes which have the same mask. 496 * We will find it useful to have a unique pointer to 497 * the mask to speed avoiding duplicate references at 498 * nodes and possibly save time in calculating indices. 499 */ 500 if (netmask) { 501 if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) 502 return (0); 503 b_leaf = x->rn_b; 504 b = -1 - x->rn_b; 505 netmask = x->rn_key; 506 } 507 /* 508 * Deal with duplicated keys: attach node to previous instance 509 */ 510 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); 511 if (keyduplicated) { 512 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { 513 if (tt->rn_mask == netmask) 514 return (0); 515 if (netmask == 0 || 516 (tt->rn_mask && 517 ((b_leaf < tt->rn_b) || /* index(netmask) > node */ 518 rn_refines(netmask, tt->rn_mask) || 519 rn_lexobetter(netmask, tt->rn_mask)))) 520 break; 521 } 522 /* 523 * If the mask is not duplicated, we wouldn't 524 * find it among possible duplicate key entries 525 * anyway, so the above test doesn't hurt. 526 * 527 * We sort the masks for a duplicated key the same way as 528 * in a masklist -- most specific to least specific. 529 * This may require the unfortunate nuisance of relocating 530 * the head of the list. 531 * 532 * We also reverse, or doubly link the list through the 533 * parent pointer. 534 */ 535 if (tt == saved_tt) { 536 struct radix_node *xx = x; 537 /* link in at head of list */ 538 (tt = treenodes)->rn_dupedkey = t; 539 tt->rn_flags = t->rn_flags; 540 tt->rn_p = x = t->rn_p; 541 t->rn_p = tt; 542 if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; 543 saved_tt = tt; x = xx; 544 } else { 545 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; 546 t->rn_dupedkey = tt; 547 tt->rn_p = t; 548 if (tt->rn_dupedkey) 549 tt->rn_dupedkey->rn_p = tt; 550 } 551 #ifdef RN_DEBUG 552 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; 553 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; 554 #endif 555 tt->rn_key = (caddr_t) v; 556 tt->rn_b = -1; 557 tt->rn_flags = RNF_ACTIVE; 558 } 559 /* 560 * Put mask in tree. 561 */ 562 if (netmask) { 563 tt->rn_mask = netmask; 564 tt->rn_b = x->rn_b; 565 tt->rn_flags |= x->rn_flags & RNF_NORMAL; 566 } 567 t = saved_tt->rn_p; 568 if (keyduplicated) 569 goto on2; 570 b_leaf = -1 - t->rn_b; 571 if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; 572 /* Promote general routes from below */ 573 if (x->rn_b < 0) { 574 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) 575 if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { 576 *mp = m = rn_new_radix_mask(x, 0); 577 if (m) 578 mp = &m->rm_mklist; 579 } 580 } else if (x->rn_mklist) { 581 /* 582 * Skip over masks whose index is > that of new node 583 */ 584 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 585 if (m->rm_b >= b_leaf) 586 break; 587 t->rn_mklist = m; *mp = 0; 588 } 589 on2: 590 /* Add new route to highest possible ancestor's list */ 591 if ((netmask == 0) || (b > t->rn_b )) 592 return tt; /* can't lift at all */ 593 b_leaf = tt->rn_b; 594 do { 595 x = t; 596 t = t->rn_p; 597 } while (b <= t->rn_b && x != top); 598 /* 599 * Search through routes associated with node to 600 * insert new route according to index. 601 * Need same criteria as when sorting dupedkeys to avoid 602 * double loop on deletion. 603 */ 604 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { 605 if (m->rm_b < b_leaf) 606 continue; 607 if (m->rm_b > b_leaf) 608 break; 609 if (m->rm_flags & RNF_NORMAL) { 610 mmask = m->rm_leaf->rn_mask; 611 if (tt->rn_flags & RNF_NORMAL) { 612 log(LOG_ERR, 613 "Non-unique normal route, mask not entered"); 614 return tt; 615 } 616 } else 617 mmask = m->rm_mask; 618 if (mmask == netmask) { 619 m->rm_refs++; 620 tt->rn_mklist = m; 621 return tt; 622 } 623 if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) 624 break; 625 } 626 *mp = rn_new_radix_mask(tt, *mp); 627 return tt; 628 } 629 630 struct radix_node * 631 rn_delete(v_arg, netmask_arg, head) 632 void *v_arg, *netmask_arg; 633 struct radix_node_head *head; 634 { 635 register struct radix_node *t, *p, *x, *tt; 636 struct radix_mask *m, *saved_m, **mp; 637 struct radix_node *dupedkey, *saved_tt, *top; 638 caddr_t v, netmask; 639 int b, head_off, vlen; 640 641 v = v_arg; 642 netmask = netmask_arg; 643 x = head->rnh_treetop; 644 tt = rn_search(v, x); 645 head_off = x->rn_off; 646 vlen = *(u_char *)v; 647 saved_tt = tt; 648 top = x; 649 if (tt == 0 || 650 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) 651 return (0); 652 /* 653 * Delete our route from mask lists. 654 */ 655 if (netmask) { 656 if ((x = rn_addmask(netmask, 1, head_off)) == 0) 657 return (0); 658 netmask = x->rn_key; 659 while (tt->rn_mask != netmask) 660 if ((tt = tt->rn_dupedkey) == 0) 661 return (0); 662 } 663 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) 664 goto on1; 665 if (tt->rn_flags & RNF_NORMAL) { 666 if (m->rm_leaf != tt || m->rm_refs > 0) { 667 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 668 return 0; /* dangling ref could cause disaster */ 669 } 670 } else { 671 if (m->rm_mask != tt->rn_mask) { 672 log(LOG_ERR, "rn_delete: inconsistent annotation\n"); 673 goto on1; 674 } 675 if (--m->rm_refs >= 0) 676 goto on1; 677 } 678 b = -1 - tt->rn_b; 679 t = saved_tt->rn_p; 680 if (b > t->rn_b) 681 goto on1; /* Wasn't lifted at all */ 682 do { 683 x = t; 684 t = t->rn_p; 685 } while (b <= t->rn_b && x != top); 686 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) 687 if (m == saved_m) { 688 *mp = m->rm_mklist; 689 MKFree(m); 690 break; 691 } 692 if (m == 0) { 693 log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); 694 if (tt->rn_flags & RNF_NORMAL) 695 return (0); /* Dangling ref to us */ 696 } 697 on1: 698 /* 699 * Eliminate us from tree 700 */ 701 if (tt->rn_flags & RNF_ROOT) 702 return (0); 703 #ifdef RN_DEBUG 704 /* Get us out of the creation list */ 705 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} 706 if (t) t->rn_ybro = tt->rn_ybro; 707 #endif 708 t = tt->rn_p; 709 dupedkey = saved_tt->rn_dupedkey; 710 if (dupedkey) { 711 /* 712 * Here, tt is the deletion target, and 713 * saved_tt is the head of the dupedkey chain. 714 */ 715 if (tt == saved_tt) { 716 x = dupedkey; x->rn_p = t; 717 if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; 718 } else { 719 /* find node in front of tt on the chain */ 720 for (x = p = saved_tt; p && p->rn_dupedkey != tt;) 721 p = p->rn_dupedkey; 722 if (p) { 723 p->rn_dupedkey = tt->rn_dupedkey; 724 if (tt->rn_dupedkey) 725 tt->rn_dupedkey->rn_p = p; 726 } else log(LOG_ERR, "rn_delete: couldn't find us\n"); 727 } 728 t = tt + 1; 729 if (t->rn_flags & RNF_ACTIVE) { 730 #ifndef RN_DEBUG 731 *++x = *t; p = t->rn_p; 732 #else 733 b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; 734 #endif 735 if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; 736 x->rn_l->rn_p = x; x->rn_r->rn_p = x; 737 } 738 goto out; 739 } 740 if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; 741 p = t->rn_p; 742 if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; 743 x->rn_p = p; 744 /* 745 * Demote routes attached to us. 746 */ 747 if (t->rn_mklist) { 748 if (x->rn_b >= 0) { 749 for (mp = &x->rn_mklist; (m = *mp);) 750 mp = &m->rm_mklist; 751 *mp = t->rn_mklist; 752 } else { 753 /* If there are any key,mask pairs in a sibling 754 duped-key chain, some subset will appear sorted 755 in the same order attached to our mklist */ 756 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) 757 if (m == x->rn_mklist) { 758 struct radix_mask *mm = m->rm_mklist; 759 x->rn_mklist = 0; 760 if (--(m->rm_refs) < 0) 761 MKFree(m); 762 m = mm; 763 } 764 if (m) 765 log(LOG_ERR, "%s %x at %x\n", 766 "rn_delete: Orphaned Mask", m, x); 767 } 768 } 769 /* 770 * We may be holding an active internal node in the tree. 771 */ 772 x = tt + 1; 773 if (t != x) { 774 #ifndef RN_DEBUG 775 *t = *x; 776 #else 777 b = t->rn_info; *t = *x; t->rn_info = b; 778 #endif 779 t->rn_l->rn_p = t; t->rn_r->rn_p = t; 780 p = x->rn_p; 781 if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; 782 } 783 out: 784 tt->rn_flags &= ~RNF_ACTIVE; 785 tt[1].rn_flags &= ~RNF_ACTIVE; 786 return (tt); 787 } 788 789 int 790 rn_walktree(h, f, w) 791 struct radix_node_head *h; 792 register int (*f)(); 793 void *w; 794 { 795 int error; 796 struct radix_node *base, *next; 797 register struct radix_node *rn = h->rnh_treetop; 798 /* 799 * This gets complicated because we may delete the node 800 * while applying the function f to it, so we need to calculate 801 * the successor node in advance. 802 */ 803 /* First time through node, go left */ 804 while (rn->rn_b >= 0) 805 rn = rn->rn_l; 806 for (;;) { 807 base = rn; 808 /* If at right child go back up, otherwise, go right */ 809 while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) 810 rn = rn->rn_p; 811 /* Find the next *leaf* since next node might vanish, too */ 812 for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) 813 rn = rn->rn_l; 814 next = rn; 815 /* Process leaves */ 816 while (rn = base) { 817 base = rn->rn_dupedkey; 818 if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) 819 return (error); 820 } 821 rn = next; 822 if (rn->rn_flags & RNF_ROOT) 823 return (0); 824 } 825 /* NOTREACHED */ 826 } 827 828 int 829 rn_inithead(head, off) 830 void **head; 831 int off; 832 { 833 register struct radix_node_head *rnh; 834 register struct radix_node *t, *tt, *ttt; 835 if (*head) 836 return (1); 837 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); 838 if (rnh == 0) 839 return (0); 840 Bzero(rnh, sizeof (*rnh)); 841 *head = rnh; 842 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); 843 ttt = rnh->rnh_nodes + 2; 844 t->rn_r = ttt; 845 t->rn_p = t; 846 tt = t->rn_l; 847 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; 848 tt->rn_b = -1 - off; 849 *ttt = *tt; 850 ttt->rn_key = rn_ones; 851 rnh->rnh_addaddr = rn_addroute; 852 rnh->rnh_deladdr = rn_delete; 853 rnh->rnh_matchaddr = rn_match; 854 rnh->rnh_lookup = rn_lookup; 855 rnh->rnh_walktree = rn_walktree; 856 rnh->rnh_treetop = t; 857 return (1); 858 } 859 860 void 861 rn_init() 862 { 863 char *cp, *cplim; 864 #ifdef KERNEL 865 struct domain *dom; 866 867 for (dom = domains; dom; dom = dom->dom_next) 868 if (dom->dom_maxrtkey > max_keylen) 869 max_keylen = dom->dom_maxrtkey; 870 #endif 871 if (max_keylen == 0) { 872 log(LOG_ERR, 873 "rn_init: radix functions require max_keylen be set\n"); 874 return; 875 } 876 R_Malloc(rn_zeros, char *, 3 * max_keylen); 877 if (rn_zeros == NULL) 878 panic("rn_init"); 879 Bzero(rn_zeros, 3 * max_keylen); 880 rn_ones = cp = rn_zeros + max_keylen; 881 addmask_key = cplim = rn_ones + max_keylen; 882 while (cp < cplim) 883 *cp++ = -1; 884 if (rn_inithead((void **)&mask_rnhead, 0) == 0) 885 panic("rn_init 2"); 886 } 887