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-rw-r--r--src/vnet/fib/ip4_fib_hash.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/src/vnet/fib/ip4_fib_hash.c b/src/vnet/fib/ip4_fib_hash.c
new file mode 100644
index 00000000000..f42cf28f53e
--- /dev/null
+++ b/src/vnet/fib/ip4_fib_hash.c
@@ -0,0 +1,249 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/fib/fib_table.h>
+#include <vnet/fib/fib_entry.h>
+#include <vnet/fib/ip4_fib.h>
+
+/*
+ * ip4_fib_hash_table_lookup_exact_match
+ *
+ * Exact match prefix lookup
+ */
+fib_node_index_t
+ip4_fib_hash_table_lookup_exact_match (const ip4_fib_hash_t *fib,
+ const ip4_address_t *addr,
+ u32 len)
+{
+ uword * hash, * result;
+ u32 key;
+
+ hash = fib->fib_entry_by_dst_address[len];
+ key = (addr->data_u32 & ip4_main.fib_masks[len]);
+
+ result = hash_get(hash, key);
+
+ if (NULL != result) {
+ return (result[0]);
+ }
+ return (FIB_NODE_INDEX_INVALID);
+}
+
+/*
+ * ip4_fib_hash_table_lookup_adj
+ *
+ * Longest prefix match
+ */
+index_t
+ip4_fib_hash_table_lookup_lb (const ip4_fib_hash_t *fib,
+ const ip4_address_t *addr)
+{
+ fib_node_index_t fei;
+
+ fei = ip4_fib_hash_table_lookup(fib, addr, 32);
+
+ if (FIB_NODE_INDEX_INVALID != fei)
+ {
+ const dpo_id_t *dpo;
+
+ dpo = fib_entry_contribute_ip_forwarding(fei);
+
+ return (dpo->dpoi_index);
+ }
+ return (INDEX_INVALID);
+}
+
+/*
+ * ip4_fib_hash_table_lookup
+ *
+ * Longest prefix match
+ */
+fib_node_index_t
+ip4_fib_hash_table_lookup (const ip4_fib_hash_t *fib,
+ const ip4_address_t *addr,
+ u32 len)
+{
+ uword * hash, * result;
+ i32 mask_len;
+ u32 key;
+
+ for (mask_len = len; mask_len >= 0; mask_len--)
+ {
+ hash = fib->fib_entry_by_dst_address[mask_len];
+ key = (addr->data_u32 & ip4_main.fib_masks[mask_len]);
+
+ result = hash_get (hash, key);
+
+ if (NULL != result) {
+ return (result[0]);
+ }
+ }
+ return (FIB_NODE_INDEX_INVALID);
+}
+
+void
+ip4_fib_hash_table_entry_insert (ip4_fib_hash_t *fib,
+ const ip4_address_t *addr,
+ u32 len,
+ fib_node_index_t fib_entry_index)
+{
+ uword * hash, * result;
+ u32 key;
+
+ key = (addr->data_u32 & ip4_main.fib_masks[len]);
+ hash = fib->fib_entry_by_dst_address[len];
+ result = hash_get (hash, key);
+
+ if (NULL == result) {
+ /*
+ * adding a new entry
+ */
+
+ if (NULL == hash) {
+ hash = hash_create (32 /* elts */, sizeof (uword));
+ hash_set_flags (hash, HASH_FLAG_NO_AUTO_SHRINK);
+
+ }
+ hash = hash_set(hash, key, fib_entry_index);
+ fib->fib_entry_by_dst_address[len] = hash;
+ }
+ else
+ {
+ ASSERT(0);
+ }
+}
+
+void
+ip4_fib_hash_table_entry_remove (ip4_fib_hash_t *fib,
+ const ip4_address_t *addr,
+ u32 len)
+{
+ uword * hash, * result;
+ u32 key;
+
+ key = (addr->data_u32 & ip4_main.fib_masks[len]);
+ hash = fib->fib_entry_by_dst_address[len];
+ result = hash_get (hash, key);
+
+ if (NULL == result)
+ {
+ /*
+ * removing a non-existent entry. i'll allow it.
+ */
+ }
+ else
+ {
+ hash_unset(hash, key);
+ }
+
+ fib->fib_entry_by_dst_address[len] = hash;
+}
+
+void
+ip4_fib_hash_table_walk (ip4_fib_hash_t *fib,
+ fib_table_walk_fn_t fn,
+ void *ctx)
+{
+ fib_prefix_t root = {
+ .fp_proto = FIB_PROTOCOL_IP4,
+ // address and length default to all 0
+ };
+
+ /*
+ * A full tree walk is the dengenerate case of a sub-tree from
+ * the very root
+ */
+ return (ip4_fib_hash_table_sub_tree_walk(fib, &root, fn, ctx));
+}
+
+void
+ip4_fib_hash_table_sub_tree_walk (ip4_fib_hash_t *fib,
+ const fib_prefix_t *root,
+ fib_table_walk_fn_t fn,
+ void *ctx)
+{
+ fib_prefix_t *sub_trees = NULL;
+ int i;
+
+ /*
+ * There is no efficient way to walk this array of hash tables.
+ * so we walk each table with a mask length greater than and equal to
+ * the required root and check it is covered by the root.
+ */
+ for (i = root->fp_len;
+ i < ARRAY_LEN (fib->fib_entry_by_dst_address);
+ i++)
+ {
+ uword * hash = fib->fib_entry_by_dst_address[i];
+
+ if (NULL != hash)
+ {
+ ip4_address_t key;
+ hash_pair_t * p;
+
+ hash_foreach_pair (p, hash,
+ ({
+ key.as_u32 = p->key;
+ if (ip4_destination_matches_route(&ip4_main,
+ &key,
+ &root->fp_addr.ip4,
+ root->fp_len))
+ {
+ const fib_prefix_t *sub_tree;
+ int skip = 0;
+
+ /*
+ * exclude sub-trees the walk does not want to explore
+ */
+ vec_foreach(sub_tree, sub_trees)
+ {
+ if (ip4_destination_matches_route(&ip4_main,
+ &key,
+ &sub_tree->fp_addr.ip4,
+ sub_tree->fp_len))
+ {
+ skip = 1;
+ break;
+ }
+ }
+
+ if (!skip)
+ {
+ switch (fn(p->value[0], ctx))
+ {
+ case FIB_TABLE_WALK_CONTINUE:
+ break;
+ case FIB_TABLE_WALK_SUB_TREE_STOP: {
+ fib_prefix_t pfx = {
+ .fp_proto = FIB_PROTOCOL_IP4,
+ .fp_len = i,
+ .fp_addr.ip4 = key,
+ };
+ vec_add1(sub_trees, pfx);
+ break;
+ }
+ case FIB_TABLE_WALK_STOP:
+ goto done;
+ }
+ }
+ }
+ }));
+ }
+ }
+done:
+ vec_free(sub_trees);
+ return;
+}
+