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- /*-
- * SPDX-License-Identifier: BSD-3-Clause
- *
- * Copyright (c) 1988, 1989, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
- /*
- * Routines to build and maintain radix trees for routing lookups.
- */
- #include <sys/param.h>
- #ifdef _KERNEL
- #include <sys/lock.h>
- #include <sys/mutex.h>
- #include <sys/rmlock.h>
- #include <sys/systm.h>
- #include <sys/malloc.h>
- #include <sys/syslog.h>
- #include <net/radix.h>
- #else /* !_KERNEL */
- #include <stdio.h>
- #include <strings.h>
- #include <stdlib.h>
- #define log(x, arg...) fprintf(stderr, ## arg)
- #define panic(x) fprintf(stderr, "PANIC: %s", x), exit(1)
- #define min(a, b) ((a) < (b) ? (a) : (b) )
- #include <net/radix.h>
- #endif /* !_KERNEL */
- static struct radix_node
- *rn_insert(void *, struct radix_head *, int *,
- struct radix_node [2]),
- *rn_newpair(void *, int, struct radix_node[2]),
- *rn_search(const void *, struct radix_node *),
- *rn_search_m(const void *, struct radix_node *, void *);
- static struct radix_node *rn_addmask(const void *, struct radix_mask_head *, int,int);
- static void rn_detachhead_internal(struct radix_head *);
- #define RADIX_MAX_KEY_LEN 32
- static char rn_zeros[RADIX_MAX_KEY_LEN];
- static char rn_ones[RADIX_MAX_KEY_LEN] = {
- -1, -1, -1, -1, -1, -1, -1, -1,
- -1, -1, -1, -1, -1, -1, -1, -1,
- -1, -1, -1, -1, -1, -1, -1, -1,
- -1, -1, -1, -1, -1, -1, -1, -1,
- };
- static int rn_lexobetter(const void *m_arg, const void *n_arg);
- static struct radix_mask *
- rn_new_radix_mask(struct radix_node *tt,
- struct radix_mask *next);
- static int rn_satisfies_leaf(const char *trial, struct radix_node *leaf,
- int skip);
- /*
- * The data structure for the keys is a radix tree with one way
- * branching removed. The index rn_bit at an internal node n represents a bit
- * position to be tested. The tree is arranged so that all descendants
- * of a node n have keys whose bits all agree up to position rn_bit - 1.
- * (We say the index of n is rn_bit.)
- *
- * There is at least one descendant which has a one bit at position rn_bit,
- * and at least one with a zero there.
- *
- * A route is determined by a pair of key and mask. We require that the
- * bit-wise logical and of the key and mask to be the key.
- * We define the index of a route to associated with the mask to be
- * the first bit number in the mask where 0 occurs (with bit number 0
- * representing the highest order bit).
- *
- * We say a mask is normal if every bit is 0, past the index of the mask.
- * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit,
- * and m is a normal mask, then the route applies to every descendant of n.
- * If the index(m) < rn_bit, this implies the trailing last few bits of k
- * before bit b are all 0, (and hence consequently true of every descendant
- * of n), so the route applies to all descendants of the node as well.
- *
- * Similar logic shows that a non-normal mask m such that
- * index(m) <= index(n) could potentially apply to many children of n.
- * Thus, for each non-host route, we attach its mask to a list at an internal
- * node as high in the tree as we can go.
- *
- * The present version of the code makes use of normal routes in short-
- * circuiting an explict mask and compare operation when testing whether
- * a key satisfies a normal route, and also in remembering the unique leaf
- * that governs a subtree.
- */
- /*
- * Most of the functions in this code assume that the key/mask arguments
- * are sockaddr-like structures, where the first byte is an u_char
- * indicating the size of the entire structure.
- *
- * To make the assumption more explicit, we use the LEN() macro to access
- * this field. It is safe to pass an expression with side effects
- * to LEN() as the argument is evaluated only once.
- * We cast the result to int as this is the dominant usage.
- */
- #define LEN(x) ( (int) (*(const u_char *)(x)) )
- /*
- * XXX THIS NEEDS TO BE FIXED
- * In the code, pointers to keys and masks are passed as either
- * 'void *' (because callers use to pass pointers of various kinds), or
- * 'caddr_t' (which is fine for pointer arithmetics, but not very
- * clean when you dereference it to access data). Furthermore, caddr_t
- * is really 'char *', while the natural type to operate on keys and
- * masks would be 'u_char'. This mismatch require a lot of casts and
- * intermediate variables to adapt types that clutter the code.
- */
- /*
- * Search a node in the tree matching the key.
- */
- static struct radix_node *
- rn_search(const void *v_arg, struct radix_node *head)
- {
- struct radix_node *x;
- c_caddr_t v;
- for (x = head, v = v_arg; x->rn_bit >= 0;) {
- if (x->rn_bmask & v[x->rn_offset])
- x = x->rn_right;
- else
- x = x->rn_left;
- }
- return (x);
- }
- /*
- * Same as above, but with an additional mask.
- * XXX note this function is used only once.
- */
- static struct radix_node *
- rn_search_m(const void *v_arg, struct radix_node *head, void *m_arg)
- {
- struct radix_node *x;
- c_caddr_t v = v_arg, m = m_arg;
- for (x = head; x->rn_bit >= 0;) {
- if ((x->rn_bmask & m[x->rn_offset]) &&
- (x->rn_bmask & v[x->rn_offset]))
- x = x->rn_right;
- else
- x = x->rn_left;
- }
- return (x);
- }
- int
- rn_refines(const void *m_arg, const void *n_arg)
- {
- c_caddr_t m = m_arg, n = n_arg;
- c_caddr_t lim, lim2 = lim = n + LEN(n);
- int longer = LEN(n++) - LEN(m++);
- int masks_are_equal = 1;
- if (longer > 0)
- lim -= longer;
- while (n < lim) {
- if (*n & ~(*m))
- return (0);
- if (*n++ != *m++)
- masks_are_equal = 0;
- }
- while (n < lim2)
- if (*n++)
- return (0);
- if (masks_are_equal && (longer < 0))
- for (lim2 = m - longer; m < lim2; )
- if (*m++)
- return (1);
- return (!masks_are_equal);
- }
- /*
- * Search for exact match in given @head.
- * Assume host bits are cleared in @v_arg if @m_arg is not NULL
- * Note that prefixes with /32 or /128 masks are treated differently
- * from host routes.
- */
- struct radix_node *
- rn_lookup(const void *v_arg, const void *m_arg, struct radix_head *head)
- {
- struct radix_node *x;
- caddr_t netmask;
- if (m_arg != NULL) {
- /*
- * Most common case: search exact prefix/mask
- */
- x = rn_addmask(m_arg, head->rnh_masks, 1,
- head->rnh_treetop->rn_offset);
- if (x == NULL)
- return (NULL);
- netmask = x->rn_key;
- x = rn_match(v_arg, head);
- while (x != NULL && x->rn_mask != netmask)
- x = x->rn_dupedkey;
- return (x);
- }
- /*
- * Search for host address.
- */
- if ((x = rn_match(v_arg, head)) == NULL)
- return (NULL);
- /* Check if found key is the same */
- if (LEN(x->rn_key) != LEN(v_arg) || bcmp(x->rn_key, v_arg, LEN(v_arg)))
- return (NULL);
- /* Check if this is not host route */
- if (x->rn_mask != NULL)
- return (NULL);
- return (x);
- }
- static int
- rn_satisfies_leaf(const char *trial, struct radix_node *leaf, int skip)
- {
- const char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
- const char *cplim;
- int length = min(LEN(cp), LEN(cp2));
- if (cp3 == NULL)
- cp3 = rn_ones;
- else
- length = min(length, LEN(cp3));
- cplim = cp + length; cp3 += skip; cp2 += skip;
- for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
- if ((*cp ^ *cp2) & *cp3)
- return (0);
- return (1);
- }
- /*
- * Search for longest-prefix match in given @head
- */
- struct radix_node *
- rn_match(const void *v_arg, struct radix_head *head)
- {
- c_caddr_t v = v_arg;
- struct radix_node *t = head->rnh_treetop, *x;
- c_caddr_t cp = v, cp2;
- c_caddr_t cplim;
- struct radix_node *saved_t, *top = t;
- int off = t->rn_offset, vlen = LEN(cp), matched_off;
- int test, b, rn_bit;
- /*
- * Open code rn_search(v, top) to avoid overhead of extra
- * subroutine call.
- */
- for (; t->rn_bit >= 0; ) {
- if (t->rn_bmask & cp[t->rn_offset])
- t = t->rn_right;
- else
- t = t->rn_left;
- }
- /*
- * See if we match exactly as a host destination
- * or at least learn how many bits match, for normal mask finesse.
- *
- * It doesn't hurt us to limit how many bytes to check
- * to the length of the mask, since if it matches we had a genuine
- * match and the leaf we have is the most specific one anyway;
- * if it didn't match with a shorter length it would fail
- * with a long one. This wins big for class B&C netmasks which
- * are probably the most common case...
- */
- if (t->rn_mask)
- vlen = *(u_char *)t->rn_mask;
- cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
- for (; cp < cplim; cp++, cp2++)
- if (*cp != *cp2)
- goto on1;
- /*
- * This extra grot is in case we are explicitly asked
- * to look up the default. Ugh!
- *
- * Never return the root node itself, it seems to cause a
- * lot of confusion.
- */
- if (t->rn_flags & RNF_ROOT)
- t = t->rn_dupedkey;
- return (t);
- on1:
- test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
- for (b = 7; (test >>= 1) > 0;)
- b--;
- matched_off = cp - v;
- b += matched_off << 3;
- rn_bit = -1 - b;
- /*
- * If there is a host route in a duped-key chain, it will be first.
- */
- if ((saved_t = t)->rn_mask == 0)
- t = t->rn_dupedkey;
- for (; t; t = t->rn_dupedkey)
- /*
- * Even if we don't match exactly as a host,
- * we may match if the leaf we wound up at is
- * a route to a net.
- */
- if (t->rn_flags & RNF_NORMAL) {
- if (rn_bit <= t->rn_bit)
- return (t);
- } else if (rn_satisfies_leaf(v, t, matched_off))
- return (t);
- t = saved_t;
- /* start searching up the tree */
- do {
- struct radix_mask *m;
- t = t->rn_parent;
- m = t->rn_mklist;
- /*
- * If non-contiguous masks ever become important
- * we can restore the masking and open coding of
- * the search and satisfaction test and put the
- * calculation of "off" back before the "do".
- */
- while (m) {
- if (m->rm_flags & RNF_NORMAL) {
- if (rn_bit <= m->rm_bit)
- return (m->rm_leaf);
- } else {
- off = min(t->rn_offset, matched_off);
- x = rn_search_m(v, t, m->rm_mask);
- while (x && x->rn_mask != m->rm_mask)
- x = x->rn_dupedkey;
- if (x && rn_satisfies_leaf(v, x, off))
- return (x);
- }
- m = m->rm_mklist;
- }
- } while (t != top);
- return (0);
- }
- /*
- * Returns the next (wider) prefix for the key defined by @rn
- * if exists.
- */
- struct radix_node *
- rn_nextprefix(struct radix_node *rn)
- {
- for (rn = rn->rn_dupedkey; rn != NULL; rn = rn->rn_dupedkey) {
- if (!(rn->rn_flags & RNF_ROOT))
- return (rn);
- }
- return (NULL);
- }
- #ifdef RN_DEBUG
- int rn_nodenum;
- struct radix_node *rn_clist;
- int rn_saveinfo;
- int rn_debug = 1;
- #endif
- /*
- * Whenever we add a new leaf to the tree, we also add a parent node,
- * so we allocate them as an array of two elements: the first one must be
- * the leaf (see RNTORT() in route.c), the second one is the parent.
- * This routine initializes the relevant fields of the nodes, so that
- * the leaf is the left child of the parent node, and both nodes have
- * (almost) all all fields filled as appropriate.
- * (XXX some fields are left unset, see the '#if 0' section).
- * The function returns a pointer to the parent node.
- */
- static struct radix_node *
- rn_newpair(void *v, int b, struct radix_node nodes[2])
- {
- struct radix_node *tt = nodes, *t = tt + 1;
- t->rn_bit = b;
- t->rn_bmask = 0x80 >> (b & 7);
- t->rn_left = tt;
- t->rn_offset = b >> 3;
- #if 0 /* XXX perhaps we should fill these fields as well. */
- t->rn_parent = t->rn_right = NULL;
- tt->rn_mask = NULL;
- tt->rn_dupedkey = NULL;
- tt->rn_bmask = 0;
- #endif
- tt->rn_bit = -1;
- tt->rn_key = (caddr_t)v;
- tt->rn_parent = t;
- tt->rn_flags = t->rn_flags = RNF_ACTIVE;
- tt->rn_mklist = t->rn_mklist = 0;
- #ifdef RN_DEBUG
- tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
- tt->rn_twin = t;
- tt->rn_ybro = rn_clist;
- rn_clist = tt;
- #endif
- return (t);
- }
- static struct radix_node *
- rn_insert(void *v_arg, struct radix_head *head, int *dupentry,
- struct radix_node nodes[2])
- {
- caddr_t v = v_arg;
- struct radix_node *top = head->rnh_treetop;
- int head_off = top->rn_offset, vlen = LEN(v);
- struct radix_node *t = rn_search(v_arg, top);
- caddr_t cp = v + head_off;
- unsigned b;
- struct radix_node *p, *tt, *x;
- /*
- * Find first bit at which v and t->rn_key differ
- */
- caddr_t cp2 = t->rn_key + head_off;
- int cmp_res;
- caddr_t cplim = v + vlen;
- while (cp < cplim)
- if (*cp2++ != *cp++)
- goto on1;
- *dupentry = 1;
- return (t);
- on1:
- *dupentry = 0;
- cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
- for (b = (cp - v) << 3; cmp_res; b--)
- cmp_res >>= 1;
- x = top;
- cp = v;
- do {
- p = x;
- if (cp[x->rn_offset] & x->rn_bmask)
- x = x->rn_right;
- else
- x = x->rn_left;
- } while (b > (unsigned) x->rn_bit);
- /* x->rn_bit < b && x->rn_bit >= 0 */
- #ifdef RN_DEBUG
- if (rn_debug)
- log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
- #endif
- t = rn_newpair(v_arg, b, nodes);
- tt = t->rn_left;
- if ((cp[p->rn_offset] & p->rn_bmask) == 0)
- p->rn_left = t;
- else
- p->rn_right = t;
- x->rn_parent = t;
- t->rn_parent = p; /* frees x, p as temp vars below */
- if ((cp[t->rn_offset] & t->rn_bmask) == 0) {
- t->rn_right = x;
- } else {
- t->rn_right = tt;
- t->rn_left = x;
- }
- #ifdef RN_DEBUG
- if (rn_debug)
- log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
- #endif
- return (tt);
- }
- static struct radix_node *
- rn_addmask(const void *n_arg, struct radix_mask_head *maskhead, int search, int skip)
- {
- const unsigned char *netmask = n_arg;
- const unsigned char *c, *clim;
- unsigned char *cp;
- struct radix_node *x;
- int b = 0, mlen, j;
- int maskduplicated, isnormal;
- struct radix_node *saved_x;
- unsigned char addmask_key[RADIX_MAX_KEY_LEN];
- if ((mlen = LEN(netmask)) > RADIX_MAX_KEY_LEN)
- mlen = RADIX_MAX_KEY_LEN;
- if (skip == 0)
- skip = 1;
- if (mlen <= skip)
- return (maskhead->mask_nodes);
- bzero(addmask_key, RADIX_MAX_KEY_LEN);
- if (skip > 1)
- bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
- bcopy(netmask + skip, addmask_key + skip, mlen - skip);
- /*
- * Trim trailing zeroes.
- */
- for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
- cp--;
- mlen = cp - addmask_key;
- if (mlen <= skip)
- return (maskhead->mask_nodes);
- *addmask_key = mlen;
- x = rn_search(addmask_key, maskhead->head.rnh_treetop);
- if (bcmp(addmask_key, x->rn_key, mlen) != 0)
- x = NULL;
- if (x || search)
- return (x);
- R_Zalloc(x, struct radix_node *, RADIX_MAX_KEY_LEN + 2 * sizeof (*x));
- if ((saved_x = x) == NULL)
- return (0);
- netmask = cp = (unsigned char *)(x + 2);
- bcopy(addmask_key, cp, mlen);
- x = rn_insert(cp, &maskhead->head, &maskduplicated, x);
- if (maskduplicated) {
- log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
- R_Free(saved_x);
- return (x);
- }
- /*
- * Calculate index of mask, and check for normalcy.
- * First find the first byte with a 0 bit, then if there are
- * more bits left (remember we already trimmed the trailing 0's),
- * the bits should be contiguous, otherwise we have got
- * a non-contiguous mask.
- */
- #define CONTIG(_c) (((~(_c) + 1) & (_c)) == (unsigned char)(~(_c) + 1))
- clim = netmask + mlen;
- isnormal = 1;
- for (c = netmask + skip; (c < clim) && *(const u_char *)c == 0xff;)
- c++;
- if (c != clim) {
- for (j = 0x80; (j & *c) != 0; j >>= 1)
- b++;
- if (!CONTIG(*c) || c != (clim - 1))
- isnormal = 0;
- }
- b += (c - netmask) << 3;
- x->rn_bit = -1 - b;
- if (isnormal)
- x->rn_flags |= RNF_NORMAL;
- return (x);
- }
- static int /* XXX: arbitrary ordering for non-contiguous masks */
- rn_lexobetter(const void *m_arg, const void *n_arg)
- {
- const u_char *mp = m_arg, *np = n_arg, *lim;
- if (LEN(mp) > LEN(np))
- return (1); /* not really, but need to check longer one first */
- if (LEN(mp) == LEN(np))
- for (lim = mp + LEN(mp); mp < lim;)
- if (*mp++ > *np++)
- return (1);
- return (0);
- }
- static struct radix_mask *
- rn_new_radix_mask(struct radix_node *tt, struct radix_mask *next)
- {
- struct radix_mask *m;
- R_Malloc(m, struct radix_mask *, sizeof (struct radix_mask));
- if (m == NULL) {
- log(LOG_ERR, "Failed to allocate route mask\n");
- return (0);
- }
- bzero(m, sizeof(*m));
- m->rm_bit = tt->rn_bit;
- m->rm_flags = tt->rn_flags;
- if (tt->rn_flags & RNF_NORMAL)
- m->rm_leaf = tt;
- else
- m->rm_mask = tt->rn_mask;
- m->rm_mklist = next;
- tt->rn_mklist = m;
- return (m);
- }
- struct radix_node *
- rn_addroute(void *v_arg, const void *n_arg, struct radix_head *head,
- struct radix_node treenodes[2])
- {
- caddr_t v = (caddr_t)v_arg, netmask = NULL;
- struct radix_node *t, *x = NULL, *tt;
- struct radix_node *saved_tt, *top = head->rnh_treetop;
- short b = 0, b_leaf = 0;
- int keyduplicated;
- caddr_t mmask;
- struct radix_mask *m, **mp;
- /*
- * In dealing with non-contiguous masks, there may be
- * many different routes which have the same mask.
- * We will find it useful to have a unique pointer to
- * the mask to speed avoiding duplicate references at
- * nodes and possibly save time in calculating indices.
- */
- if (n_arg) {
- x = rn_addmask(n_arg, head->rnh_masks, 0, top->rn_offset);
- if (x == NULL)
- return (0);
- b_leaf = x->rn_bit;
- b = -1 - x->rn_bit;
- netmask = x->rn_key;
- }
- /*
- * Deal with duplicated keys: attach node to previous instance
- */
- saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes);
- if (keyduplicated) {
- for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
- if (tt->rn_mask == netmask)
- return (0);
- if (netmask == 0 ||
- (tt->rn_mask &&
- ((b_leaf < tt->rn_bit) /* index(netmask) > node */
- || rn_refines(netmask, tt->rn_mask)
- || rn_lexobetter(netmask, tt->rn_mask))))
- break;
- }
- /*
- * If the mask is not duplicated, we wouldn't
- * find it among possible duplicate key entries
- * anyway, so the above test doesn't hurt.
- *
- * We sort the masks for a duplicated key the same way as
- * in a masklist -- most specific to least specific.
- * This may require the unfortunate nuisance of relocating
- * the head of the list.
- *
- * We also reverse, or doubly link the list through the
- * parent pointer.
- */
- if (tt == saved_tt) {
- struct radix_node *xx = x;
- /* link in at head of list */
- (tt = treenodes)->rn_dupedkey = t;
- tt->rn_flags = t->rn_flags;
- tt->rn_parent = x = t->rn_parent;
- t->rn_parent = tt; /* parent */
- if (x->rn_left == t)
- x->rn_left = tt;
- else
- x->rn_right = tt;
- saved_tt = tt; x = xx;
- } else {
- (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
- t->rn_dupedkey = tt;
- tt->rn_parent = t; /* parent */
- if (tt->rn_dupedkey) /* parent */
- tt->rn_dupedkey->rn_parent = tt; /* parent */
- }
- #ifdef RN_DEBUG
- t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
- tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
- #endif
- tt->rn_key = (caddr_t) v;
- tt->rn_bit = -1;
- tt->rn_flags = RNF_ACTIVE;
- }
- /*
- * Put mask in tree.
- */
- if (netmask) {
- tt->rn_mask = netmask;
- tt->rn_bit = x->rn_bit;
- tt->rn_flags |= x->rn_flags & RNF_NORMAL;
- }
- t = saved_tt->rn_parent;
- if (keyduplicated)
- goto on2;
- b_leaf = -1 - t->rn_bit;
- if (t->rn_right == saved_tt)
- x = t->rn_left;
- else
- x = t->rn_right;
- /* Promote general routes from below */
- if (x->rn_bit < 0) {
- for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
- if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) {
- *mp = m = rn_new_radix_mask(x, 0);
- if (m)
- mp = &m->rm_mklist;
- }
- } else if (x->rn_mklist) {
- /*
- * Skip over masks whose index is > that of new node
- */
- for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
- if (m->rm_bit >= b_leaf)
- break;
- t->rn_mklist = m; *mp = NULL;
- }
- on2:
- /* Add new route to highest possible ancestor's list */
- if ((netmask == 0) || (b > t->rn_bit ))
- return (tt); /* can't lift at all */
- b_leaf = tt->rn_bit;
- do {
- x = t;
- t = t->rn_parent;
- } while (b <= t->rn_bit && x != top);
- /*
- * Search through routes associated with node to
- * insert new route according to index.
- * Need same criteria as when sorting dupedkeys to avoid
- * double loop on deletion.
- */
- for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
- if (m->rm_bit < b_leaf)
- continue;
- if (m->rm_bit > b_leaf)
- break;
- if (m->rm_flags & RNF_NORMAL) {
- mmask = m->rm_leaf->rn_mask;
- if (tt->rn_flags & RNF_NORMAL) {
- log(LOG_ERR,
- "Non-unique normal route, mask not entered\n");
- return (tt);
- }
- } else
- mmask = m->rm_mask;
- if (mmask == netmask) {
- m->rm_refs++;
- tt->rn_mklist = m;
- return (tt);
- }
- if (rn_refines(netmask, mmask)
- || rn_lexobetter(netmask, mmask))
- break;
- }
- *mp = rn_new_radix_mask(tt, *mp);
- return (tt);
- }
- struct radix_node *
- rn_delete(const void *v_arg, const void *netmask_arg, struct radix_head *head)
- {
- struct radix_node *t, *p, *x, *tt;
- struct radix_mask *m, *saved_m, **mp;
- struct radix_node *dupedkey, *saved_tt, *top;
- c_caddr_t v;
- c_caddr_t netmask;
- int b, head_off, vlen;
- v = v_arg;
- netmask = netmask_arg;
- x = head->rnh_treetop;
- tt = rn_search(v, x);
- head_off = x->rn_offset;
- vlen = LEN(v);
- saved_tt = tt;
- top = x;
- if (tt == NULL ||
- bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
- return (0);
- /*
- * Delete our route from mask lists.
- */
- if (netmask) {
- x = rn_addmask(netmask, head->rnh_masks, 1, head_off);
- if (x == NULL)
- return (0);
- netmask = x->rn_key;
- while (tt->rn_mask != netmask)
- if ((tt = tt->rn_dupedkey) == NULL)
- return (0);
- }
- if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == NULL)
- goto on1;
- if (tt->rn_flags & RNF_NORMAL) {
- if (m->rm_leaf != tt || m->rm_refs > 0) {
- log(LOG_ERR, "rn_delete: inconsistent annotation\n");
- return (0); /* dangling ref could cause disaster */
- }
- } else {
- if (m->rm_mask != tt->rn_mask) {
- log(LOG_ERR, "rn_delete: inconsistent annotation\n");
- goto on1;
- }
- if (--m->rm_refs >= 0)
- goto on1;
- }
- b = -1 - tt->rn_bit;
- t = saved_tt->rn_parent;
- if (b > t->rn_bit)
- goto on1; /* Wasn't lifted at all */
- do {
- x = t;
- t = t->rn_parent;
- } while (b <= t->rn_bit && x != top);
- for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
- if (m == saved_m) {
- *mp = m->rm_mklist;
- R_Free(m);
- break;
- }
- if (m == NULL) {
- log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
- if (tt->rn_flags & RNF_NORMAL)
- return (0); /* Dangling ref to us */
- }
- on1:
- /*
- * Eliminate us from tree
- */
- if (tt->rn_flags & RNF_ROOT)
- return (0);
- #ifdef RN_DEBUG
- /* Get us out of the creation list */
- for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
- if (t) t->rn_ybro = tt->rn_ybro;
- #endif
- t = tt->rn_parent;
- dupedkey = saved_tt->rn_dupedkey;
- if (dupedkey) {
- /*
- * Here, tt is the deletion target and
- * saved_tt is the head of the dupekey chain.
- */
- if (tt == saved_tt) {
- /* remove from head of chain */
- x = dupedkey; x->rn_parent = t;
- if (t->rn_left == tt)
- t->rn_left = x;
- else
- t->rn_right = x;
- } else {
- /* find node in front of tt on the chain */
- for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
- p = p->rn_dupedkey;
- if (p) {
- p->rn_dupedkey = tt->rn_dupedkey;
- if (tt->rn_dupedkey) /* parent */
- tt->rn_dupedkey->rn_parent = p;
- /* parent */
- } else log(LOG_ERR, "rn_delete: couldn't find us\n");
- }
- t = tt + 1;
- if (t->rn_flags & RNF_ACTIVE) {
- #ifndef RN_DEBUG
- *++x = *t;
- p = t->rn_parent;
- #else
- b = t->rn_info;
- *++x = *t;
- t->rn_info = b;
- p = t->rn_parent;
- #endif
- if (p->rn_left == t)
- p->rn_left = x;
- else
- p->rn_right = x;
- x->rn_left->rn_parent = x;
- x->rn_right->rn_parent = x;
- }
- goto out;
- }
- if (t->rn_left == tt)
- x = t->rn_right;
- else
- x = t->rn_left;
- p = t->rn_parent;
- if (p->rn_right == t)
- p->rn_right = x;
- else
- p->rn_left = x;
- x->rn_parent = p;
- /*
- * Demote routes attached to us.
- */
- if (t->rn_mklist) {
- if (x->rn_bit >= 0) {
- for (mp = &x->rn_mklist; (m = *mp);)
- mp = &m->rm_mklist;
- *mp = t->rn_mklist;
- } else {
- /* If there are any key,mask pairs in a sibling
- duped-key chain, some subset will appear sorted
- in the same order attached to our mklist */
- for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
- if (m == x->rn_mklist) {
- struct radix_mask *mm = m->rm_mklist;
- x->rn_mklist = 0;
- if (--(m->rm_refs) < 0)
- R_Free(m);
- m = mm;
- }
- if (m)
- log(LOG_ERR,
- "rn_delete: Orphaned Mask %p at %p\n",
- m, x);
- }
- }
- /*
- * We may be holding an active internal node in the tree.
- */
- x = tt + 1;
- if (t != x) {
- #ifndef RN_DEBUG
- *t = *x;
- #else
- b = t->rn_info;
- *t = *x;
- t->rn_info = b;
- #endif
- t->rn_left->rn_parent = t;
- t->rn_right->rn_parent = t;
- p = x->rn_parent;
- if (p->rn_left == x)
- p->rn_left = t;
- else
- p->rn_right = t;
- }
- out:
- tt->rn_flags &= ~RNF_ACTIVE;
- tt[1].rn_flags &= ~RNF_ACTIVE;
- return (tt);
- }
- /*
- * This is the same as rn_walktree() except for the parameters and the
- * exit.
- */
- int
- rn_walktree_from(struct radix_head *h, void *a, void *m,
- walktree_f_t *f, void *w)
- {
- int error;
- struct radix_node *base, *next;
- u_char *xa = (u_char *)a;
- u_char *xm = (u_char *)m;
- struct radix_node *rn, *last = NULL; /* shut up gcc */
- int stopping = 0;
- int lastb;
- KASSERT(m != NULL, ("%s: mask needs to be specified", __func__));
- /*
- * rn_search_m is sort-of-open-coded here. We cannot use the
- * function because we need to keep track of the last node seen.
- */
- /* printf("about to search\n"); */
- for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) {
- last = rn;
- /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n",
- rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */
- if (!(rn->rn_bmask & xm[rn->rn_offset])) {
- break;
- }
- if (rn->rn_bmask & xa[rn->rn_offset]) {
- rn = rn->rn_right;
- } else {
- rn = rn->rn_left;
- }
- }
- /* printf("done searching\n"); */
- /*
- * Two cases: either we stepped off the end of our mask,
- * in which case last == rn, or we reached a leaf, in which
- * case we want to start from the leaf.
- */
- if (rn->rn_bit >= 0)
- rn = last;
- lastb = last->rn_bit;
- /* printf("rn %p, lastb %d\n", rn, lastb);*/
- /*
- * This gets complicated because we may delete the node
- * while applying the function f to it, so we need to calculate
- * the successor node in advance.
- */
- while (rn->rn_bit >= 0)
- rn = rn->rn_left;
- while (!stopping) {
- /* printf("node %p (%d)\n", rn, rn->rn_bit); */
- base = rn;
- /* If at right child go back up, otherwise, go right */
- while (rn->rn_parent->rn_right == rn
- && !(rn->rn_flags & RNF_ROOT)) {
- rn = rn->rn_parent;
- /* if went up beyond last, stop */
- if (rn->rn_bit <= lastb) {
- stopping = 1;
- /* printf("up too far\n"); */
- /*
- * XXX we should jump to the 'Process leaves'
- * part, because the values of 'rn' and 'next'
- * we compute will not be used. Not a big deal
- * because this loop will terminate, but it is
- * inefficient and hard to understand!
- */
- }
- }
-
- /*
- * At the top of the tree, no need to traverse the right
- * half, prevent the traversal of the entire tree in the
- * case of default route.
- */
- if (rn->rn_parent->rn_flags & RNF_ROOT)
- stopping = 1;
- /* Find the next *leaf* since next node might vanish, too */
- for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
- rn = rn->rn_left;
- next = rn;
- /* Process leaves */
- while ((rn = base) != NULL) {
- base = rn->rn_dupedkey;
- /* printf("leaf %p\n", rn); */
- if (!(rn->rn_flags & RNF_ROOT)
- && (error = (*f)(rn, w)))
- return (error);
- }
- rn = next;
- if (rn->rn_flags & RNF_ROOT) {
- /* printf("root, stopping"); */
- stopping = 1;
- }
- }
- return (0);
- }
- int
- rn_walktree(struct radix_head *h, walktree_f_t *f, void *w)
- {
- int error;
- struct radix_node *base, *next;
- struct radix_node *rn = h->rnh_treetop;
- /*
- * This gets complicated because we may delete the node
- * while applying the function f to it, so we need to calculate
- * the successor node in advance.
- */
- /* First time through node, go left */
- while (rn->rn_bit >= 0)
- rn = rn->rn_left;
- for (;;) {
- base = rn;
- /* If at right child go back up, otherwise, go right */
- while (rn->rn_parent->rn_right == rn
- && (rn->rn_flags & RNF_ROOT) == 0)
- rn = rn->rn_parent;
- /* Find the next *leaf* since next node might vanish, too */
- for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
- rn = rn->rn_left;
- next = rn;
- /* Process leaves */
- while ((rn = base)) {
- base = rn->rn_dupedkey;
- if (!(rn->rn_flags & RNF_ROOT)
- && (error = (*f)(rn, w)))
- return (error);
- }
- rn = next;
- if (rn->rn_flags & RNF_ROOT)
- return (0);
- }
- /* NOTREACHED */
- }
- /*
- * Initialize an empty tree. This has 3 nodes, which are passed
- * via base_nodes (in the order <left,root,right>) and are
- * marked RNF_ROOT so they cannot be freed.
- * The leaves have all-zero and all-one keys, with significant
- * bits starting at 'off'.
- */
- void
- rn_inithead_internal(struct radix_head *rh, struct radix_node *base_nodes, int off)
- {
- struct radix_node *t, *tt, *ttt;
- t = rn_newpair(rn_zeros, off, base_nodes);
- ttt = base_nodes + 2;
- t->rn_right = ttt;
- t->rn_parent = t;
- tt = t->rn_left; /* ... which in turn is base_nodes */
- tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
- tt->rn_bit = -1 - off;
- *ttt = *tt;
- ttt->rn_key = rn_ones;
- rh->rnh_treetop = t;
- }
- static void
- rn_detachhead_internal(struct radix_head *head)
- {
- KASSERT((head != NULL),
- ("%s: head already freed", __func__));
- /* Free <left,root,right> nodes. */
- R_Free(head);
- }
- /* Functions used by 'struct radix_node_head' users */
- int
- rn_inithead(void **head, int off)
- {
- struct radix_node_head *rnh;
- struct radix_mask_head *rmh;
- rnh = *head;
- rmh = NULL;
- if (*head != NULL)
- return (1);
- R_Zalloc(rnh, struct radix_node_head *, sizeof (*rnh));
- R_Zalloc(rmh, struct radix_mask_head *, sizeof (*rmh));
- if (rnh == NULL || rmh == NULL) {
- if (rnh != NULL)
- R_Free(rnh);
- if (rmh != NULL)
- R_Free(rmh);
- return (0);
- }
- /* Init trees */
- rn_inithead_internal(&rnh->rh, rnh->rnh_nodes, off);
- rn_inithead_internal(&rmh->head, rmh->mask_nodes, 0);
- *head = rnh;
- rnh->rh.rnh_masks = rmh;
- /* Finally, set base callbacks */
- rnh->rnh_addaddr = rn_addroute;
- rnh->rnh_deladdr = rn_delete;
- rnh->rnh_matchaddr = rn_match;
- rnh->rnh_lookup = rn_lookup;
- rnh->rnh_walktree = rn_walktree;
- rnh->rnh_walktree_from = rn_walktree_from;
- return (1);
- }
- static int
- rn_freeentry(struct radix_node *rn, void *arg)
- {
- struct radix_head * const rnh = arg;
- struct radix_node *x;
- x = (struct radix_node *)rn_delete(rn + 2, NULL, rnh);
- if (x != NULL)
- R_Free(x);
- return (0);
- }
- int
- rn_detachhead(void **head)
- {
- struct radix_node_head *rnh;
- KASSERT((head != NULL && *head != NULL),
- ("%s: head already freed", __func__));
- rnh = (struct radix_node_head *)(*head);
- rn_walktree(&rnh->rh.rnh_masks->head, rn_freeentry, rnh->rh.rnh_masks);
- rn_detachhead_internal(&rnh->rh.rnh_masks->head);
- rn_detachhead_internal(&rnh->rh);
- *head = NULL;
- return (1);
- }
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