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Diffstat (limited to 'src/vnet/util/radix.c')
| -rw-r--r-- | src/vnet/util/radix.c | 1104 |
1 files changed, 1104 insertions, 0 deletions
diff --git a/src/vnet/util/radix.c b/src/vnet/util/radix.c new file mode 100644 index 00000000..ff0b0f7b --- /dev/null +++ b/src/vnet/util/radix.c @@ -0,0 +1,1104 @@ +/* $NetBSD: radix.c,v 1.47 2016/12/12 03:55:57 ozaki-r Exp $ */ + +/* + * 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. + * + * @(#)radix.c 8.6 (Berkeley) 10/17/95 + */ + +/* + * Routines to build and maintain radix trees for routing lookups. + */ + +#include <vnet/util/radix.h> + +typedef void (*rn_printer_t)(void *, const char *fmt, ...); + +static int max_keylen = 33; // me +struct radix_mask *rn_mkfreelist; +struct radix_node_head *mask_rnhead; +static char *addmask_key; +static const char normal_chars[] = + {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; +static char *rn_zeros, *rn_ones; + +#define rn_masktop (mask_rnhead->rnh_treetop) + +static int rn_satisfies_leaf(const char *, struct radix_node *, int); +static int rn_lexobetter(const void *, const void *); +static struct radix_mask *rn_new_radix_mask(struct radix_node *, + struct radix_mask *); +static struct radix_node *rn_walknext(struct radix_node *, rn_printer_t, + void *); +static struct radix_node *rn_walkfirst(struct radix_node *, rn_printer_t, + void *); +static void rn_nodeprint(struct radix_node *, rn_printer_t, void *, + const char *); + +#define SUBTREE_OPEN "[ " +#define SUBTREE_CLOSE " ]" + +#ifdef RN_DEBUG +static void rn_treeprint(struct radix_node_head *, rn_printer_t, void *); +#endif /* RN_DEBUG */ + +#define MIN(x,y) (((x)<(y))?(x):(y)) + +static struct radix_mask* +rm_alloc (void) +{ + struct radix_mask *rm = clib_mem_alloc(sizeof(struct radix_mask)); + + memset(rm, 0, sizeof(*rm)); + + return (rm); +} + +static void +rm_free (struct radix_mask *rm) +{ + clib_mem_free(rm); +} + +#define R_Malloc(p, t, n) \ +{ \ + p = (t) clib_mem_alloc((unsigned int)(n)); \ + memset(p, 0, n); \ +} +#define Free(p) clib_mem_free((p)) +#define log(a,b, c...) +#define bool i32 + +/* + * The data structure for the keys is a radix tree with one way + * branching removed. The index rn_b 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_b - 1. + * (We say the index of n is rn_b.) + * + * There is at least one descendant which has a one bit at position rn_b, + * 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_b, + * and m is a normal mask, then the route applies to every descendant of n. + * If the index(m) < rn_b, 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 explicit mask and compare operation when testing whether + * a key satisfies a normal route, and also in remembering the unique leaf + * that governs a subtree. + */ + +struct radix_node * +rn_search( + const void *v_arg, + struct radix_node *head) +{ + const u8 * const v = v_arg; + struct radix_node *x; + + for (x = head; x->rn_b >= 0;) { + if (x->rn_bmask & v[x->rn_off]) + x = x->rn_r; + else + x = x->rn_l; + } + return x; +} + +struct radix_node * +rn_search_m( + const void *v_arg, + struct radix_node *head, + const void *m_arg) +{ + struct radix_node *x; + const u8 * const v = v_arg; + const u8 * const m = m_arg; + + for (x = head; x->rn_b >= 0;) { + if ((x->rn_bmask & m[x->rn_off]) && + (x->rn_bmask & v[x->rn_off])) + x = x->rn_r; + else + x = x->rn_l; + } + return x; +} + +int +rn_refines( + const void *m_arg, + const void *n_arg) +{ + const char *m = m_arg; + const char *n = n_arg; + const char *lim = n + *(const u8 *)n; + const char *lim2 = lim; + int longer = (*(const u8 *)n++) - (int)(*(const u8 *)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; +} + +struct radix_node * +rn_lookup( + const void *v_arg, + const void *m_arg, + struct radix_node_head *head) +{ + struct radix_node *x; + const char *netmask = NULL; + + if (m_arg) { + if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) + return NULL; + netmask = x->rn_key; + } + x = rn_match(v_arg, head); + if (x != NULL && netmask != NULL) { + while (x != NULL && x->rn_mask != netmask) + x = x->rn_dupedkey; + } + return x; +} + +static int +rn_satisfies_leaf( + const char *trial, + struct radix_node *leaf, + int skip) +{ + const char *cp = trial; + const char *cp2 = leaf->rn_key; + const char *cp3 = leaf->rn_mask; + const char *cplim; + int length = MIN(*(const u8 *)cp, *(const u8 *)cp2); + + if (cp3 == 0) + cp3 = rn_ones; + else + length = MIN(length, *(const u8 *)cp3); + cplim = cp + length; cp3 += skip; cp2 += skip; + for (cp += skip; cp < cplim; cp++, cp2++, cp3++) + if ((*cp ^ *cp2) & *cp3) + return 0; + return 1; +} + +struct radix_node * +rn_match( + const void *v_arg, + struct radix_node_head *head) +{ + const char * const v = v_arg; + struct radix_node *t = head->rnh_treetop; + struct radix_node *top = t; + struct radix_node *x; + struct radix_node *saved_t; + const char *cp = v; + const char *cp2; + const char *cplim; + int off = t->rn_off; + int vlen = *(const u8 *)cp; + int matched_off; + int test, b, rn_b; + + /* + * Open code rn_search(v, top) to avoid overhead of extra + * subroutine call. + */ + for (; t->rn_b >= 0; ) { + if (t->rn_bmask & cp[t->rn_off]) + t = t->rn_r; + else + t = t->rn_l; + } + /* + * 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 = *(const u8 *)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! + */ + if ((t->rn_flags & RNF_ROOT) && t->rn_dupedkey) + 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_b = -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_b <= t->rn_b) + 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_p; + m = t->rn_mklist; + if (m) { + /* + * 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". + */ + do { + if (m->rm_flags & RNF_NORMAL) { + if (rn_b <= m->rm_b) + return m->rm_leaf; + } else { + off = MIN(t->rn_off, 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 (m); + } + } while (t != top); + return NULL; +} + +static void +rn_nodeprint(struct radix_node *rn, rn_printer_t printer, void *arg, + const char *delim) +{ + (*printer)(arg, "%s(%s%p: p<%p> l<%p> r<%p>)", + delim, ((void *)rn == arg) ? "*" : "", rn, rn->rn_p, + rn->rn_l, rn->rn_r); +} + +#ifdef RN_DEBUG +int rn_debug = 1; + +static void +rn_dbg_print(void *arg, const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + vlog(LOG_DEBUG, fmt, ap); + va_end(ap); +} + +static void +rn_treeprint(struct radix_node_head *h, rn_printer_t printer, void *arg) +{ + struct radix_node *dup, *rn; + const char *delim; + + if (printer == NULL) + return; + + rn = rn_walkfirst(h->rnh_treetop, printer, arg); + for (;;) { + /* Process leaves */ + delim = ""; + for (dup = rn; dup != NULL; dup = dup->rn_dupedkey) { + if ((dup->rn_flags & RNF_ROOT) != 0) + continue; + rn_nodeprint(dup, printer, arg, delim); + delim = ", "; + } + rn = rn_walknext(rn, printer, arg); + if (rn->rn_flags & RNF_ROOT) + return; + } + /* NOTREACHED */ +} + +#define traverse(__head, __rn) rn_treeprint((__head), rn_dbg_print, (__rn)) +#endif /* RN_DEBUG */ + +struct radix_node * +rn_newpair( + const void *v, + int b, + struct radix_node nodes[2]) +{ + struct radix_node *tt = nodes; + struct radix_node *t = tt + 1; + t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); + t->rn_l = tt; t->rn_off = b >> 3; + tt->rn_b = -1; tt->rn_key = v; tt->rn_p = t; + tt->rn_flags = t->rn_flags = RNF_ACTIVE; + return t; +} + +struct radix_node * +rn_insert( + const void *v_arg, + struct radix_node_head *head, + int *dupentry, + struct radix_node nodes[2]) +{ + struct radix_node *top = head->rnh_treetop; + struct radix_node *t = rn_search(v_arg, top); + struct radix_node *tt; + const char *v = v_arg; + int head_off = top->rn_off; + int vlen = *((const u8 *)v); + const char *cp = v + head_off; + int b; + /* + * Find first bit at which v and t->rn_key differ + */ + { + const char *cp2 = t->rn_key + head_off; + const char *cplim = v + vlen; + int cmp_res; + + 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; + } + { + struct radix_node *p, *x = top; + cp = v; + do { + p = x; + if (cp[x->rn_off] & x->rn_bmask) + x = x->rn_r; + else x = x->rn_l; + } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ +#ifdef RN_DEBUG + if (rn_debug) + log(LOG_DEBUG, "%s: Going In:\n", __func__), traverse(head, p); +#endif + t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; + if ((cp[p->rn_off] & p->rn_bmask) == 0) + p->rn_l = t; + else + p->rn_r = t; + x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ + if ((cp[t->rn_off] & t->rn_bmask) == 0) { + t->rn_r = x; + } else { + t->rn_r = tt; t->rn_l = x; + } +#ifdef RN_DEBUG + if (rn_debug) { + log(LOG_DEBUG, "%s: Coming Out:\n", __func__), + traverse(head, p); + } +#endif /* RN_DEBUG */ + } + return tt; +} + +struct radix_node * +rn_addmask( + const void *n_arg, + int search, + int skip) +{ + const char *netmask = n_arg; + const char *cp; + const char *cplim; + struct radix_node *x; + struct radix_node *saved_x; + int b = 0, mlen, j; + int maskduplicated, m0, isnormal; + static int last_zeroed = 0; + + if ((mlen = *(const u8 *)netmask) > max_keylen) + mlen = max_keylen; + if (skip == 0) + skip = 1; + if (mlen <= skip) + return mask_rnhead->rnh_nodes; + if (skip > 1) + memmove(addmask_key + 1, rn_ones + 1, skip - 1); + if ((m0 = mlen) > skip) + memmove(addmask_key + skip, netmask + 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) { + if (m0 >= last_zeroed) + last_zeroed = mlen; + return mask_rnhead->rnh_nodes; + } + if (m0 < last_zeroed) + memset(addmask_key + m0, 0, last_zeroed - m0); + *addmask_key = last_zeroed = mlen; + x = rn_search(addmask_key, rn_masktop); + if (memcmp(addmask_key, x->rn_key, mlen) != 0) + x = 0; + if (x || search) + return x; + R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); + if ((saved_x = x) == NULL) + return NULL; + memset(x, 0, max_keylen + 2 * sizeof (*x)); + cp = netmask = (void *)(x + 2); + memmove(x + 2, addmask_key, mlen); + x = rn_insert(cp, mask_rnhead, &maskduplicated, x); + if (maskduplicated) { + log(LOG_ERR, "rn_addmask: mask impossibly already in tree\n"); + Free(saved_x); + return x; + } + /* + * Calculate index of mask, and check for normalcy. + */ + cplim = netmask + mlen; isnormal = 1; + for (cp = netmask + skip; (cp < cplim) && *(const u8 *)cp == 0xff;) + cp++; + if (cp != cplim) { + for (j = 0x80; (j & *cp) != 0; j >>= 1) + b++; + if (*cp != normal_chars[b] || cp != (cplim - 1)) + isnormal = 0; + } + b += (cp - netmask) << 3; + x->rn_b = -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 u8 *mp = m_arg; + const u8 *np = n_arg; + const u8 *lim; + + if (*mp > *np) + return 1; /* not really, but need to check longer one first */ + if (*mp == *np) + for (lim = mp + *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; + + m = rm_alloc(); + if (m == NULL) { + log(LOG_ERR, "Mask for route not entered\n"); + return NULL; + } + memset(m, 0, sizeof(*m)); + m->rm_b = tt->rn_b; + 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( + const void *v_arg, + const void *n_arg, + struct radix_node_head *head, + struct radix_node treenodes[2]) +{ + const char *v = v_arg, *netmask = n_arg; + struct radix_node *t, *x = NULL, *tt; + struct radix_node *saved_tt, *top = head->rnh_treetop; + short b = 0, b_leaf = 0; + int keyduplicated; + const char *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 (netmask != NULL) { + if ((x = rn_addmask(netmask, 0, top->rn_off)) == NULL) + return NULL; + b_leaf = x->rn_b; + b = -1 - x->rn_b; + 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 != NULL; t = tt, tt = tt->rn_dupedkey) { + if (tt->rn_mask == netmask) + return NULL; + if (netmask == NULL || + (tt->rn_mask != NULL && + (b_leaf < tt->rn_b || /* 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_p = x = t->rn_p; + t->rn_p = tt; + if (x->rn_l == t) + x->rn_l = tt; + else + x->rn_r = tt; + saved_tt = tt; + x = xx; + } else { + (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; + t->rn_dupedkey = tt; + tt->rn_p = t; + if (tt->rn_dupedkey) + tt->rn_dupedkey->rn_p = tt; + } + tt->rn_key = v; + tt->rn_b = -1; + tt->rn_flags = RNF_ACTIVE; + } + /* + * Put mask in tree. + */ + if (netmask != NULL) { + tt->rn_mask = netmask; + tt->rn_b = x->rn_b; + tt->rn_flags |= x->rn_flags & RNF_NORMAL; + } + t = saved_tt->rn_p; + if (keyduplicated) + goto on2; + b_leaf = -1 - t->rn_b; + if (t->rn_r == saved_tt) + x = t->rn_l; + else + x = t->rn_r; + /* Promote general routes from below */ + if (x->rn_b < 0) { + for (mp = &t->rn_mklist; x != NULL; x = x->rn_dupedkey) { + if (x->rn_mask != NULL && x->rn_b >= b_leaf && + x->rn_mklist == NULL) { + *mp = m = rn_new_radix_mask(x, NULL); + if (m != NULL) + mp = &m->rm_mklist; + } + } + } else if (x->rn_mklist != NULL) { + /* + * Skip over masks whose index is > that of new node + */ + for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) + if (m->rm_b >= b_leaf) + break; + t->rn_mklist = m; + *mp = NULL; + } +on2: + /* Add new route to highest possible ancestor's list */ + if (netmask == NULL || b > t->rn_b) + return tt; /* can't lift at all */ + b_leaf = tt->rn_b; + do { + x = t; + t = t->rn_p; + } while (b <= t->rn_b && 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) != NULL; mp = &m->rm_mklist) { + if (m->rm_b < b_leaf) + continue; + if (m->rm_b > 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_delete1( + const void *v_arg, + const void *netmask_arg, + struct radix_node_head *head, + struct radix_node *rn) +{ + struct radix_node *t, *p, *x, *tt; + struct radix_mask *m, *saved_m, **mp; + struct radix_node *dupedkey, *saved_tt, *top; + const char *v, *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_off; + vlen = *(const u8 *)v; + saved_tt = tt; + top = x; + if (tt == NULL || + memcmp(v + head_off, tt->rn_key + head_off, vlen - head_off) != 0) + return NULL; + /* + * Delete our route from mask lists. + */ + if (netmask != NULL) { + if ((x = rn_addmask(netmask, 1, head_off)) == NULL) + return NULL; + netmask = x->rn_key; + while (tt->rn_mask != netmask) + if ((tt = tt->rn_dupedkey) == NULL) + return NULL; + } + if (tt->rn_mask == NULL || (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 NULL; /* 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_b; + t = saved_tt->rn_p; + if (b > t->rn_b) + goto on1; /* Wasn't lifted at all */ + do { + x = t; + t = t->rn_p; + } while (b <= t->rn_b && x != top); + for (mp = &x->rn_mklist; (m = *mp) != NULL; mp = &m->rm_mklist) { + if (m == saved_m) { + *mp = m->rm_mklist; + rm_free(m); + break; + } + } + if (m == NULL) { + log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); + if (tt->rn_flags & RNF_NORMAL) + return NULL; /* Dangling ref to us */ + } +on1: + /* + * Eliminate us from tree + */ + if (tt->rn_flags & RNF_ROOT) + return NULL; +#ifdef RN_DEBUG + if (rn_debug) + log(LOG_DEBUG, "%s: Going In:\n", __func__), traverse(head, tt); +#endif + t = tt->rn_p; + dupedkey = saved_tt->rn_dupedkey; + if (dupedkey != NULL) { + /* + * Here, tt is the deletion target, and + * saved_tt is the head of the dupedkey chain. + */ + if (tt == saved_tt) { + x = dupedkey; + x->rn_p = t; + if (t->rn_l == tt) + t->rn_l = x; + else + t->rn_r = x; + } else { + /* find node in front of tt on the chain */ + for (x = p = saved_tt; + p != NULL && p->rn_dupedkey != tt;) + p = p->rn_dupedkey; + if (p != NULL) { + p->rn_dupedkey = tt->rn_dupedkey; + if (tt->rn_dupedkey != NULL) + tt->rn_dupedkey->rn_p = p; + } else + log(LOG_ERR, "rn_delete: couldn't find us\n"); + } + t = tt + 1; + if (t->rn_flags & RNF_ACTIVE) { + *++x = *t; + p = t->rn_p; + if (p->rn_l == t) + p->rn_l = x; + else + p->rn_r = x; + x->rn_l->rn_p = x; + x->rn_r->rn_p = x; + } + goto out; + } + if (t->rn_l == tt) + x = t->rn_r; + else + x = t->rn_l; + p = t->rn_p; + if (p->rn_r == t) + p->rn_r = x; + else + p->rn_l = x; + x->rn_p = p; + /* + * Demote routes attached to us. + */ + if (t->rn_mklist == NULL) + ; + else if (x->rn_b >= 0) { + for (mp = &x->rn_mklist; (m = *mp) != NULL; 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 != NULL && x != NULL; + x = x->rn_dupedkey) { + if (m == x->rn_mklist) { + struct radix_mask *mm = m->rm_mklist; + x->rn_mklist = NULL; + if (--(m->rm_refs) < 0) + rm_free(m); + m = mm; + } + } + if (m != NULL) { + 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) { + *t = *x; + t->rn_l->rn_p = t; + t->rn_r->rn_p = t; + p = x->rn_p; + if (p->rn_l == x) + p->rn_l = t; + else + p->rn_r = t; + } +out: +#ifdef RN_DEBUG + if (rn_debug) { + log(LOG_DEBUG, "%s: Coming Out:\n", __func__), + traverse(head, tt); + } +#endif /* RN_DEBUG */ + tt->rn_flags &= ~RNF_ACTIVE; + tt[1].rn_flags &= ~RNF_ACTIVE; + return tt; +} + +struct radix_node * +rn_delete( + const void *v_arg, + const void *netmask_arg, + struct radix_node_head *head) +{ + return rn_delete1(v_arg, netmask_arg, head, NULL); +} + +static struct radix_node * +rn_walknext(struct radix_node *rn, rn_printer_t printer, void *arg) +{ + /* If at right child go back up, otherwise, go right */ + while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) { + if (printer != NULL) + (*printer)(arg, SUBTREE_CLOSE); + rn = rn->rn_p; + } + if (printer) + rn_nodeprint(rn->rn_p, printer, arg, ""); + /* Find the next *leaf* since next node might vanish, too */ + for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) { + if (printer != NULL) + (*printer)(arg, SUBTREE_OPEN); + rn = rn->rn_l; + } + return rn; +} + +static struct radix_node * +rn_walkfirst(struct radix_node *rn, rn_printer_t printer, void *arg) +{ + /* First time through node, go left */ + while (rn->rn_b >= 0) { + if (printer != NULL) + (*printer)(arg, SUBTREE_OPEN); + rn = rn->rn_l; + } + return rn; +} + +int +rn_walktree( + struct radix_node_head *h, + int (*f)(struct radix_node *, void *), + void *w) +{ + int error; + struct radix_node *base, *next, *rn; + /* + * 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. + */ + rn = rn_walkfirst(h->rnh_treetop, NULL, NULL); + for (;;) { + base = rn; + next = rn_walknext(rn, NULL, NULL); + /* Process leaves */ + while ((rn = base) != NULL) { + 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 */ +} + +struct radix_node * +rn_search_matched(struct radix_node_head *h, + int (*matcher)(struct radix_node *, void *), void *w) +{ + bool matched; + struct radix_node *base, *next, *rn; + /* + * 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. + */ + rn = rn_walkfirst(h->rnh_treetop, NULL, NULL); + for (;;) { + base = rn; + next = rn_walknext(rn, NULL, NULL); + /* Process leaves */ + while ((rn = base) != NULL) { + base = rn->rn_dupedkey; + if (!(rn->rn_flags & RNF_ROOT)) { + matched = (*matcher)(rn, w); + if (matched) + return rn; + } + } + rn = next; + if (rn->rn_flags & RNF_ROOT) + return NULL; + } + /* NOTREACHED */ +} + +int +rn_inithead(void **head, int off) +{ + struct radix_node_head *rnh; + + if (*head != NULL) + return 1; + R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); + if (rnh == NULL) + return 0; + *head = rnh; + return rn_inithead0(rnh, off); +} + +int +rn_inithead0(struct radix_node_head *rnh, int off) +{ + struct radix_node *t; + struct radix_node *tt; + struct radix_node *ttt; + + memset(rnh, 0, sizeof(*rnh)); + t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); + ttt = rnh->rnh_nodes + 2; + t->rn_r = ttt; + t->rn_p = t; + tt = t->rn_l; + tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; + tt->rn_b = -1 - off; + *ttt = *tt; + ttt->rn_key = rn_ones; + rnh->rnh_addaddr = rn_addroute; + rnh->rnh_deladdr = rn_delete; + rnh->rnh_matchaddr = rn_match; + rnh->rnh_lookup = rn_lookup; + rnh->rnh_treetop = t; + return 1; +} + +static clib_error_t * +rn_module_init (vlib_main_t * vm) +{ + char *cp, *cplim; + + R_Malloc(rn_zeros, char *, 3 * max_keylen); + if (rn_zeros == NULL) + return (clib_error_return (0, "RN Zeros...")); + + memset(rn_zeros, 0, 3 * max_keylen); + rn_ones = cp = rn_zeros + max_keylen; + addmask_key = cplim = rn_ones + max_keylen; + while (cp < cplim) + *cp++ = -1; + if (rn_inithead((void *)&mask_rnhead, 0) == 0) + return (clib_error_return (0, "RN Init 2")); + + return (NULL); +} + +VLIB_INIT_FUNCTION(rn_module_init); |