IP Multicast FIB (mfib)

 - IPv[46] mfib tables with support for (*,G/m), (*,G) and (S,G) exact and longest prefix match
 - Replication represented via a new replicate DPO.
 - RPF configuration and data-plane checking
 - data-plane signals sent to listening control planes.

The functions of multicast forwarding entries differ from their unicast conterparts, so we introduce a new mfib_table_t and mfib_entry_t objects. However, we re-use the fib_path_list to resolve and build the entry's output list. the fib_path_list provides the service to construct a replicate DPO for multicast.

'make tests' is added to with two new suites; TEST=mfib, this is invocation of the CLI command 'test mfib' which deals with many path add/remove, flag set/unset scenarios, TEST=ip-mcast, data-plane forwarding tests.

Updated applications to use the new MIFB functions;
  - IPv6 NS/RA.
  - DHCPv6
 unit tests for these are undated accordingly.

Change-Id: I49ec37b01f1b170335a5697541c8fd30e6d3a961
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 465 insertions, 0 deletions

diff --git a/src/vnet/mfib/ip4_mfib.c b/src/vnet/mfib/ip4_mfib.c
new file mode 100644
index 00000000000..08001c3fa7a
--- /dev/null
+++ b/src/vnet/mfib/ip4_mfib.c
@@ -0,0 +1,465 @@
+/*
+ * 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/mfib/ip4_mfib.h>
+
+#include <vnet/mfib/mfib_table.h>
+#include <vnet/mfib/mfib_entry.h>
+
+static const mfib_prefix_t ip4_specials[] = {
+    {
+        /* (*,*)/0 */
+        .fp_src_addr = {
+            .ip4.data_u32 = 0,
+        },
+        .fp_grp_addr = {
+            .ip4.data_u32 = 0,
+        },
+        .fp_len  = 0,
+        .fp_proto = FIB_PROTOCOL_IP4,
+    },
+};
+
+static u32
+ip4_create_mfib_with_table_id (u32 table_id)
+{
+    mfib_table_t *mfib_table;
+
+    pool_get_aligned(ip4_main.mfibs, mfib_table, CLIB_CACHE_LINE_BYTES);
+    memset(mfib_table, 0, sizeof(*mfib_table));
+
+    mfib_table->mft_proto = FIB_PROTOCOL_IP4;
+    mfib_table->mft_index =
+        mfib_table->v4.index =
+            (mfib_table - ip4_main.mfibs);
+
+    hash_set (ip4_main.mfib_index_by_table_id,
+              table_id,
+              mfib_table->mft_index);
+
+    mfib_table->mft_table_id =
+        mfib_table->v4.table_id =
+            table_id;
+
+    mfib_table_lock(mfib_table->mft_index, FIB_PROTOCOL_IP4);
+
+    /*
+     * add the special entries into the new FIB
+     */
+    int ii;
+
+    for (ii = 0; ii < ARRAY_LEN(ip4_specials); ii++)
+    {
+        mfib_prefix_t prefix = ip4_specials[ii];
+
+        prefix.fp_src_addr.ip4.data_u32 =
+            clib_host_to_net_u32(prefix.fp_src_addr.ip4.data_u32);
+        prefix.fp_grp_addr.ip4.data_u32 =
+            clib_host_to_net_u32(prefix.fp_grp_addr.ip4.data_u32);
+
+        mfib_table_entry_update(mfib_table->mft_index,
+                                &prefix,
+                                MFIB_SOURCE_DEFAULT_ROUTE,
+                                MFIB_ENTRY_FLAG_DROP);
+    }
+
+    return (mfib_table->mft_index);
+}
+
+void
+ip4_mfib_table_destroy (ip4_mfib_t *mfib)
+{
+    mfib_table_t *mfib_table = (mfib_table_t*)mfib;
+    int ii;
+
+    /*
+     * remove all the specials we added when the table was created.
+     */
+    for (ii = 0; ii < ARRAY_LEN(ip4_specials); ii++)
+    {
+        fib_node_index_t mfei;
+        mfib_prefix_t prefix = ip4_specials[ii];
+
+        prefix.fp_src_addr.ip4.data_u32 =
+            clib_host_to_net_u32(prefix.fp_src_addr.ip4.data_u32);
+        prefix.fp_grp_addr.ip4.data_u32 =
+            clib_host_to_net_u32(prefix.fp_grp_addr.ip4.data_u32);
+
+        mfei = mfib_table_lookup(mfib_table->mft_index, &prefix);
+        mfib_table_entry_delete_index(mfei, MFIB_SOURCE_DEFAULT_ROUTE);
+    }
+
+    /*
+     * validate no more routes.
+     */
+    ASSERT(0 == mfib_table->mft_total_route_counts);
+    ASSERT(~0 != mfib_table->mft_table_id);
+
+    hash_unset (ip4_main.mfib_index_by_table_id, mfib_table->mft_table_id);
+    pool_put(ip4_main.mfibs, mfib_table);
+}
+
+u32
+ip4_mfib_table_find_or_create_and_lock (u32 table_id)
+{
+    u32 index;
+
+    index = ip4_mfib_index_from_table_id(table_id);
+    if (~0 == index)
+        return ip4_create_mfib_with_table_id(table_id);
+    mfib_table_lock(index, FIB_PROTOCOL_IP4);
+
+    return (index);
+}
+
+u32
+ip4_mfib_table_get_index_for_sw_if_index (u32 sw_if_index)
+{
+    if (sw_if_index >= vec_len(ip4_main.mfib_index_by_sw_if_index))
+    {
+        /*
+         * This is the case for interfaces that are not yet mapped to
+         * a IP table
+         */
+        return (~0);
+    }
+    return (ip4_main.mfib_index_by_sw_if_index[sw_if_index]);
+}
+
+#define IPV4_MFIB_GRP_LEN(_len)\
+    (_len > 32 ? 32 : _len)
+
+#define IP4_MFIB_MK_KEY(_grp, _src, _len, _key)                         \
+{                                                                       \
+    _key  = ((u64)(_grp->data_u32 &                                     \
+                   ip4_main.fib_masks[IPV4_MFIB_GRP_LEN(_len)])) << 32; \
+    _key |= _src->data_u32;                                             \
+}
+#define IP4_MFIB_MK_GRP_KEY(_grp, _len, _key)                           \
+{                                                                       \
+    _key  = ((u64)(_grp->data_u32 &                                     \
+                   ip4_main.fib_masks[IPV4_MFIB_GRP_LEN(_len)])) << 32; \
+}
+
+/*
+ * ip4_fib_table_lookup_exact_match
+ *
+ * Exact match prefix lookup
+ */
+fib_node_index_t
+ip4_mfib_table_lookup_exact_match (const ip4_mfib_t *mfib,
+                                   const ip4_address_t *grp,
+                                   const ip4_address_t *src,
+                                   u32 len)
+{
+    uword * hash, * result;
+    u64 key;
+
+    hash = mfib->fib_entry_by_dst_address[len];
+    IP4_MFIB_MK_KEY(grp, src, len, key);
+
+    result = hash_get(hash, key);
+
+    if (NULL != result) {
+        return (result[0]);
+    }
+    return (FIB_NODE_INDEX_INVALID);
+}
+
+/*
+ * ip4_fib_table_lookup
+ *
+ * Longest prefix match
+ */
+fib_node_index_t
+ip4_mfib_table_lookup (const ip4_mfib_t *mfib,
+                       const ip4_address_t *src,
+                       const ip4_address_t *grp,
+                       u32 len)
+{
+    uword * hash, * result;
+    i32 mask_len;
+    u64 key;
+
+    mask_len = len;
+
+    if (PREDICT_TRUE(64 == mask_len))
+    {
+        hash = mfib->fib_entry_by_dst_address[mask_len];
+        IP4_MFIB_MK_KEY(grp, src, mask_len, key);
+
+        result = hash_get (hash, key);
+
+        if (NULL != result) {
+            return (result[0]);
+        }
+    }
+
+    for (mask_len = 32; mask_len >= 0; mask_len--)
+    {
+        hash = mfib->fib_entry_by_dst_address[mask_len];
+        IP4_MFIB_MK_GRP_KEY(grp, mask_len, key);
+
+        result = hash_get (hash, key);
+
+        if (NULL != result) {
+            return (result[0]);
+        }
+    }
+    return (FIB_NODE_INDEX_INVALID);
+}
+
+void
+ip4_mfib_table_entry_insert (ip4_mfib_t *mfib,
+                             const ip4_address_t *grp,
+                             const ip4_address_t *src,
+                             u32 len,
+                             fib_node_index_t fib_entry_index)
+{
+    uword * hash, * result;
+    u64 key;
+
+    IP4_MFIB_MK_KEY(grp, src, len, key);
+    hash = mfib->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);
+        mfib->fib_entry_by_dst_address[len] = hash;
+    }
+    else
+    {
+        ASSERT(0);
+    }
+}
+
+void
+ip4_mfib_table_entry_remove (ip4_mfib_t *mfib,
+                             const ip4_address_t *grp,
+                             const ip4_address_t *src,
+                             u32 len)
+{
+    uword * hash, * result;
+    u64 key;
+
+    IP4_MFIB_MK_KEY(grp, src, len, key);
+    hash = mfib->fib_entry_by_dst_address[len];
+    result = hash_get (hash, key);
+
+    if (NULL == result)
+    {
+        /*
+         * removing a non-existant entry. i'll allow it.
+         */
+    }
+    else
+    {
+        hash_unset(hash, key);
+    }
+
+    mfib->fib_entry_by_dst_address[len] = hash;
+}
+
+static void
+ip4_mfib_table_show_all (ip4_mfib_t *mfib,
+                         vlib_main_t * vm)
+{
+    fib_node_index_t *mfib_entry_indicies;
+    fib_node_index_t *mfib_entry_index;
+    int i;
+
+    mfib_entry_indicies = NULL;
+
+    for (i = 0; i < ARRAY_LEN (mfib->fib_entry_by_dst_address); i++)
+    {
+        uword * hash = mfib->fib_entry_by_dst_address[i];
+
+        if (NULL != hash)
+        {
+            hash_pair_t * p;
+
+            hash_foreach_pair (p, hash,
+            ({
+                vec_add1(mfib_entry_indicies, p->value[0]);
+            }));
+        }
+    }
+
+    vec_sort_with_function(mfib_entry_indicies, mfib_entry_cmp_for_sort);
+
+    vec_foreach(mfib_entry_index, mfib_entry_indicies)
+    {
+        vlib_cli_output(vm, "%U",
+                        format_mfib_entry,
+                        *mfib_entry_index,
+                        MFIB_ENTRY_FORMAT_BRIEF);
+    }
+
+    vec_free(mfib_entry_indicies);
+}
+
+static void
+ip4_mfib_table_show_one (ip4_mfib_t *mfib,
+                         vlib_main_t * vm,
+                         ip4_address_t *src,
+                         ip4_address_t *grp,
+                         u32 mask_len)
+{
+    vlib_cli_output(vm, "%U",
+                    format_mfib_entry,
+                    ip4_mfib_table_lookup(mfib, src, grp, mask_len),
+                    MFIB_ENTRY_FORMAT_DETAIL);
+}
+
+static clib_error_t *
+ip4_show_mfib (vlib_main_t * vm,
+               unformat_input_t * input,
+               vlib_cli_command_t * cmd)
+{
+    ip4_main_t * im4 = &ip4_main;
+    mfib_table_t *mfib_table;
+    int verbose, matching;
+    ip4_address_t grp, src = {{0}};
+    u32 mask = 32;
+    int i, table_id = -1, fib_index = ~0;
+
+    verbose = 1;
+    matching = 0;
+
+    while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+        if (unformat (input, "brief") || unformat (input, "summary")
+            || unformat (input, "sum"))
+            verbose = 0;
+
+        else if (unformat (input, "%U %U",
+                           unformat_ip4_address, &src,
+                           unformat_ip4_address, &grp))
+        {
+            matching = 1;
+            mask = 64;
+        }
+        else if (unformat (input, "%U", unformat_ip4_address, &grp))
+        {
+            matching = 1;
+            mask = 32;
+        }
+        else if (unformat (input, "%U/%d",
+                           unformat_ip4_address, &grp, &mask))
+            matching = 1;
+        else if (unformat (input, "table %d", &table_id))
+            ;
+        else if (unformat (input, "index %d", &fib_index))
+            ;
+        else
+            break;
+    }
+
+    pool_foreach (mfib_table, im4->mfibs,
+    ({
+        ip4_mfib_t *mfib = &mfib_table->v4;
+
+        if (table_id >= 0 && table_id != (int)mfib->table_id)
+            continue;
+        if (fib_index != ~0 && fib_index != (int)mfib->index)
+            continue;
+
+        vlib_cli_output (vm, "%U, fib_index %d",
+                         format_mfib_table_name, mfib->index, FIB_PROTOCOL_IP4,
+                         mfib->index);
+
+        /* Show summary? */
+        if (! verbose)
+        {
+            vlib_cli_output (vm, "%=20s%=16s", "Prefix length", "Count");
+            for (i = 0; i < ARRAY_LEN (mfib->fib_entry_by_dst_address); i++)
+            {
+                uword * hash = mfib->fib_entry_by_dst_address[i];
+                uword n_elts = hash_elts (hash);
+                if (n_elts > 0)
+                    vlib_cli_output (vm, "%20d%16d", i, n_elts);
+            }
+            continue;
+        }
+
+        if (!matching)
+        {
+            ip4_mfib_table_show_all(mfib, vm);
+        }
+        else
+        {
+            ip4_mfib_table_show_one(mfib, vm, &src, &grp, mask);
+        }
+    }));
+
+    return 0;
+}
+
+/*?
+ * This command displays the IPv4 MulticasrFIB Tables (VRF Tables) and
+ * the route entries for each table.
+ *
+ * @note This command will run for a long time when the FIB tables are
+ * comprised of millions of entries. For those senarios, consider displaying
+ * a single table or summary mode.
+ *
+ * @cliexpar
+ * Example of how to display all the IPv4 Multicast FIB tables:
+ * @cliexstart{show ip fib}
+ * ipv4-VRF:0, fib_index 0
+ * (*, 0.0.0.0/0):  flags:D,
+ *  Interfaces:
+ *  multicast-ip4-chain
+ *   [@1]: dpo-drop ip4
+ * (*, 232.1.1.1/32):
+ * Interfaces:
+ *  test-eth1: Forward,
+ *  test-eth2: Forward,
+ *  test-eth0: Accept,
+ * multicast-ip4-chain
+ * [@2]: dpo-replicate: [index:1 buckets:2 to:[0:0]]
+ *   [0] [@1]: ipv4-mcast: test-eth1: IP4: d0:d1:d2:d3:d4:01 -> 01:00:05:00:00:00
+ *   [1] [@1]: ipv4-mcast: test-eth2: IP4: d0:d1:d2:d3:d4:02 -> 01:00:05:00:00:00
+ *
+ * @cliexend
+ * Example of how to display a summary of all IPv4 FIB tables:
+ * @cliexstart{show ip fib summary}
+ * ipv4-VRF:0, fib_index 0, flow hash: src dst sport dport proto
+ *     Prefix length         Count
+ *                    0               1
+ *                    8               2
+ *                   32               4
+ * ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
+ *     Prefix length         Count
+ *                    0               1
+ *                    8               2
+ *                   24               2
+ *                   32               4
+ * @cliexend
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (ip4_show_fib_command, static) = {
+    .path = "show ip mfib",
+    .short_help = "show ip mfib [summary] [table <table-id>] [index <fib-id>] [<gre-addr>[/<mask>]] [<gre-addr>] [<src-addr> <gre-addr>]",
+    .function = ip4_show_mfib,
+};
+/* *INDENT-ON* */