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-rw-r--r--filter/trie.c94
1 files changed, 45 insertions, 49 deletions
diff --git a/filter/trie.c b/filter/trie.c
index fb405de..522eb99 100644
--- a/filter/trie.c
+++ b/filter/trie.c
@@ -14,7 +14,7 @@
* indicates the index of the bit in the address that is used to
* branch at the node. If we need to represent just a set of
* prefixes, it would be simple, but we have to represent a
- * set of prefix pattern. Each prefix pattern consists of
+ * set of prefix patterns. Each prefix pattern consists of
* &ppaddr/&pplen and two integers: &low and &high, and a prefix
* &paddr/&plen matches that pattern if the first MIN(&plen, &pplen)
* bits of &paddr and &ppaddr are the same and &low <= &plen <= &high.
@@ -65,8 +65,8 @@
* - we are beyond the end of path (node length > &plen)
* - we are still on path and keep walking (node length < &plen)
*
- * The walking code in add_node_to_trie() and trie_match_prefix()
- * is structured according to these cases.
+ * The walking code in trie_match_prefix() is structured according to
+ * these cases.
*/
#include "nest/bird.h"
@@ -80,17 +80,18 @@
* Allocates and returns a new empty trie.
*/
struct f_trie *
-f_new_trie(void)
+f_new_trie(linpool *lp)
{
struct f_trie * ret;
- ret = cfg_allocz(sizeof(struct f_trie));
+ ret = lp_allocz(lp, sizeof(struct f_trie));
+ ret->lp = lp;
return ret;
}
static inline struct f_trie_node *
-new_node(int plen, ip_addr paddr, ip_addr pmask, ip_addr amask)
+new_node(struct f_trie *t, int plen, ip_addr paddr, ip_addr pmask, ip_addr amask)
{
- struct f_trie_node *n = cfg_allocz(sizeof(struct f_trie_node));
+ struct f_trie_node *n = lp_allocz(t->lp, sizeof(struct f_trie_node));
n->plen = plen;
n->addr = paddr;
n->mask = pmask;
@@ -104,11 +105,33 @@ attach_node(struct f_trie_node *parent, struct f_trie_node *child)
parent->c[ipa_getbit(child->addr, parent->plen) ? 1 : 0] = child;
}
-static void
-add_node_to_trie(struct f_trie *t, int plen, ip_addr ip, ip_addr amask)
+/**
+ * trie_add_prefix
+ * @t: trie to add to
+ * @px: prefix address
+ * @plen: prefix length
+ * @l: prefix lower bound
+ * @h: prefix upper bound
+ *
+ * Adds prefix (prefix pattern) @px/@plen to trie @t. @l and @h are lower
+ * and upper bounds on accepted prefix lengths, both inclusive. 0 <=
+ * l, h <= 32 (128 for IPv6).
+ */
+
+void
+trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h)
{
+ if (l == 0)
+ t->zero = 1;
+ else
+ l--;
+
+ if (h < plen)
+ plen = h;
+
+ ip_addr amask = ipa_xor(ipa_mkmask(l), ipa_mkmask(h));
ip_addr pmask = ipa_mkmask(plen);
- ip_addr paddr = ipa_and(ip, pmask);
+ ip_addr paddr = ipa_and(px, pmask);
struct f_trie_node *o = NULL;
struct f_trie_node *n = &t->root;
@@ -123,13 +146,13 @@ add_node_to_trie(struct f_trie *t, int plen, ip_addr ip, ip_addr amask)
as the other child of 'b'. */
int blen = ipa_pxlen(paddr, n->addr);
ip_addr bmask = ipa_mkmask(blen);
- ip_addr baddr = ipa_and(ip, bmask);
+ ip_addr baddr = ipa_and(px, bmask);
/* Merge accept masks from children to get accept mask for node 'b' */
ip_addr baccm = ipa_and(ipa_or(amask, n->accept), bmask);
- struct f_trie_node *a = new_node(plen, paddr, pmask, amask);
- struct f_trie_node *b = new_node(blen, baddr, bmask, baccm);
+ struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask);
+ struct f_trie_node *b = new_node(t, blen, baddr, bmask, baccm);
attach_node(o, b);
attach_node(b, n);
attach_node(b, a);
@@ -140,7 +163,7 @@ add_node_to_trie(struct f_trie *t, int plen, ip_addr ip, ip_addr amask)
{
/* We add new node 'a' between node 'o' and node 'n' */
amask = ipa_or(amask, ipa_and(n->accept, pmask));
- struct f_trie_node *a = new_node(plen, paddr, pmask, amask);
+ struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask);
attach_node(o, a);
attach_node(a, n);
return;
@@ -156,58 +179,31 @@ add_node_to_trie(struct f_trie *t, int plen, ip_addr ip, ip_addr amask)
/* Update accept mask part M2 and go deeper */
n->accept = ipa_or(n->accept, ipa_and(amask, n->mask));
- /* n->plen < plen and plen <= 32 */
+ /* n->plen < plen and plen <= 32 (128) */
o = n;
n = n->c[ipa_getbit(paddr, n->plen) ? 1 : 0];
}
/* We add new tail node 'a' after node 'o' */
- struct f_trie_node *a = new_node(plen, paddr, pmask, amask);
+ struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask);
attach_node(o, a);
}
/**
- * trie_add_prefix
- * @t: trie to add to
- * @px: prefix to add
- *
- * Adds prefix (prefix pattern) @px to trie @t.
- */
-void
-trie_add_prefix(struct f_trie *t, struct f_prefix *px)
-{
- int l, h;
- int plen = px->len & LEN_MASK;
-
- /* 'l' and 'h' are lower and upper bounds on accepted
- prefix lengths, both inclusive. 0 <= l, h <= 32 */
- f_prefix_get_bounds(px, &l, &h);
-
- if (l == 0)
- t->zero = 1;
- else
- l--;
-
- ip_addr amask = ipa_xor(ipa_mkmask(l), ipa_mkmask(h));
- /* MIN(plen, h) instead of just plen is a little trick. */
- add_node_to_trie(t, MIN(plen, h), px->ip, amask);
-}
-
-/**
- * trie_match_prefix
+ * trie_match
* @t: trie
- * @px: prefix
+ * @px: prefix address
+ * @plen: prefix length
*
* Tries to find a matching prefix pattern in the trie such that
- * prefix @px matches that prefix pattern. Returns 1 if there
+ * prefix @px/@plen matches that prefix pattern. Returns 1 if there
* is such prefix pattern in the trie.
*/
int
-trie_match_prefix(struct f_trie *t, struct f_prefix *px)
+trie_match_prefix(struct f_trie *t, ip_addr px, int plen)
{
- int plen = px->len & LEN_MASK;
ip_addr pmask = ipa_mkmask(plen);
- ip_addr paddr = ipa_and(px->ip, pmask);
+ ip_addr paddr = ipa_and(px, pmask);
if (plen == 0)
return t->zero;