IP mcast: allow unicast address as a next-hop

Change-Id: I5e679f2601e37688f2768620479dc2efb7d19ca3
Signed-off-by: Neale Ranns <nranns@cisco.com>

4 files changed, 279 insertions, 38 deletions

diff --git a/src/vnet/mfib/mfib_entry.c b/src/vnet/mfib/mfib_entry.c
index bc7f7dec406..a88f375ec19 100644
--- a/src/vnet/mfib/mfib_entry.c
+++ b/src/vnet/mfib/mfib_entry.c
@@ -217,7 +217,10 @@ format_mfib_entry (u8 * s, va_list * args)
     ({
         s = format(s, "\n  %U", format_mfib_itf, mfi);
     }));
-    s = format(s, "\n  RPF-ID:%d", mfib_entry->mfe_rpf_id);
+    if (MFIB_RPF_ID_NONE != mfib_entry->mfe_rpf_id)
+    {
+        s = format(s, "\n  RPF-ID:%d", mfib_entry->mfe_rpf_id);
+    }
     s = format(s, "\n  %U-chain\n  %U",
                format_fib_forw_chain_type,
                mfib_entry_get_default_chain_type(mfib_entry),
@@ -835,9 +838,9 @@ mfib_entry_path_update (fib_node_index_t mfib_entry_index,
 {
     fib_node_index_t path_index;
     mfib_path_ext_t *path_ext;
-    mfib_itf_flags_t old, new;
     mfib_entry_t *mfib_entry;
     mfib_entry_src_t *msrc;
+    mfib_itf_flags_t old;
 
     mfib_entry = mfib_entry_get(mfib_entry_index);
     ASSERT(NULL != mfib_entry);
@@ -873,37 +876,32 @@ mfib_entry_path_update (fib_node_index_t mfib_entry_index,
     {
         mfib_itf_t *mfib_itf;
 
-        new = itf_flags;
-
-        if (old != new)
+        if (old != itf_flags)
         {
-            if (MFIB_ITF_FLAG_NONE == new)
-            {
-                /*
-                 * no more interface flags on this path, remove
-                 * from the data-plane set
-                 */
-                mfib_entry_itf_remove(msrc, rpath[0].frp_sw_if_index);
-            }
-            else if (MFIB_ITF_FLAG_NONE == old)
+            /*
+             * change of flag contributions
+             */
+            mfib_itf = mfib_entry_itf_find(msrc->mfes_itfs,
+                                           rpath[0].frp_sw_if_index);
+
+            if (NULL == mfib_itf)
             {
-                /*
-                 * This interface is now contributing
-                 */
                 mfib_entry_itf_add(msrc,
                                    rpath[0].frp_sw_if_index,
-                                   mfib_itf_create(rpath[0].frp_sw_if_index,
-                                                   itf_flags));
+                                   mfib_itf_create(path_index, itf_flags));
             }
             else
             {
-                /*
-                 * change of flag contributions
-                 */
-                mfib_itf = mfib_entry_itf_find(msrc->mfes_itfs,
-                                               rpath[0].frp_sw_if_index);
-                /* Seen by packets inflight */
-                mfib_itf->mfi_flags = new;
+                if (mfib_itf_update(mfib_itf,
+                                    path_index,
+                                    itf_flags))
+                {
+                    /*
+                     * no more interface flags on this path, remove
+                     * from the data-plane set
+                     */
+                    mfib_entry_itf_remove(msrc, rpath[0].frp_sw_if_index);
+                }
             }
         }
     }
@@ -952,7 +950,21 @@ mfib_entry_path_remove (fib_node_index_t mfib_entry_index,
         mfib_path_ext_remove(msrc, path_index);
         if (~0 != rpath[0].frp_sw_if_index)
         {
-            mfib_entry_itf_remove(msrc, rpath[0].frp_sw_if_index);
+            mfib_itf_t *mfib_itf;
+
+            mfib_itf = mfib_entry_itf_find(msrc->mfes_itfs,
+                                           rpath[0].frp_sw_if_index);
+
+            if (mfib_itf_update(mfib_itf,
+                                path_index,
+                                MFIB_ITF_FLAG_NONE))
+            {
+                /*
+                 * no more interface flags on this path, remove
+                 * from the data-plane set
+                 */
+                mfib_entry_itf_remove(msrc, rpath[0].frp_sw_if_index);
+            }
         }
     }
 
diff --git a/src/vnet/mfib/mfib_itf.c b/src/vnet/mfib/mfib_itf.c
index f77b40e743a..33ef98764e2 100644
--- a/src/vnet/mfib/mfib_itf.c
+++ b/src/vnet/mfib/mfib_itf.c
@@ -17,11 +17,12 @@
 
 #include <vnet/mfib/mfib_itf.h>
 #include <vnet/mfib/mfib_signal.h>
+#include <vnet/fib/fib_path.h>
 
 mfib_itf_t *mfib_itf_pool;
 
 index_t
-mfib_itf_create (u32 sw_if_index,
+mfib_itf_create (fib_node_index_t path_index,
                  mfib_itf_flags_t mfi_flags)
 {
     mfib_itf_t *mfib_itf;
@@ -29,16 +30,89 @@ mfib_itf_create (u32 sw_if_index,
     pool_get_aligned(mfib_itf_pool, mfib_itf,
                      CLIB_CACHE_LINE_BYTES);
 
-    mfib_itf->mfi_sw_if_index = sw_if_index;
-    mfib_itf->mfi_flags = mfi_flags;
+    mfib_itf->mfi_sw_if_index = fib_path_get_resolving_interface(path_index);
     mfib_itf->mfi_si = INDEX_INVALID;
 
+    /*
+     * add the path index to the per-path hash
+     */
+    mfib_itf->mfi_hash = hash_set(mfib_itf->mfi_hash, path_index, mfi_flags);
+
+    /*
+     * the combined flags from all the paths is from just the one contributor
+     */
+    mfib_itf->mfi_flags = mfi_flags;
+
     return (mfib_itf - mfib_itf_pool);
 }
 
+static mfib_itf_flags_t
+mfib_itf_mk_flags (const mfib_itf_t *mfib_itf)
+{
+    mfib_itf_flags_t combined_flags, flags;
+    fib_node_index_t *path_index;
+
+    combined_flags = MFIB_ITF_FLAG_NONE;
+
+    hash_foreach(path_index, flags, mfib_itf->mfi_hash,
+    {
+        combined_flags |= flags;
+    });
+
+    return (combined_flags);
+}
+
+int
+mfib_itf_update (mfib_itf_t *mfib_itf,
+                 fib_node_index_t path_index,
+                 mfib_itf_flags_t mfi_flags)
+{
+    /*
+     * add or remove the path index to the per-path hash
+     */
+    if (MFIB_ITF_FLAG_NONE == mfi_flags)
+    {
+        hash_unset(mfib_itf->mfi_hash, path_index);
+    }
+    else
+    {
+        mfib_itf->mfi_hash = hash_set(mfib_itf->mfi_hash,
+                                      path_index,
+                                      mfi_flags);
+    }
+
+    /*
+     * re-generate the combined flags from all the paths.
+     */
+    mfib_itf->mfi_flags = mfib_itf_mk_flags(mfib_itf);
+
+    /*
+     * The interface can be removed if there are no more flags
+     */
+    return (MFIB_ITF_FLAG_NONE == mfib_itf->mfi_flags);
+}
+
+static void
+mfib_itf_hash_flush (mfib_itf_t *mfi)
+{
+    fib_node_index_t path_index, *path_indexp, *all = NULL;
+    mfib_itf_flags_t flags;
+
+    hash_foreach(path_index, flags, mfi->mfi_hash,
+    {
+        vec_add1(all, path_index);
+    });
+
+    vec_foreach(path_indexp, all)
+    {
+        hash_unset(mfi->mfi_hash, *path_indexp);
+    };
+}
+
 void
 mfib_itf_delete (mfib_itf_t *mfi)
 {
+    mfib_itf_hash_flush(mfi);
     mfib_signal_remove_itf(mfi);
     pool_put(mfib_itf_pool, mfi);
 }
diff --git a/src/vnet/mfib/mfib_itf.h b/src/vnet/mfib/mfib_itf.h
index 5f26a476525..fe39c895d8b 100644
--- a/src/vnet/mfib/mfib_itf.h
+++ b/src/vnet/mfib/mfib_itf.h
@@ -25,7 +25,7 @@
 typedef struct mfib_itf_t_
 {
     /**
-     * @brief Falags on the entry
+     * @brief Forwarding Flags on the entry - checked in the data-path
      */
     mfib_itf_flags_t mfi_flags;
 
@@ -38,22 +38,43 @@ typedef struct mfib_itf_t_
      * The index of the signal in the pending list
      */
     u32 mfi_si;
+
+    /**
+     * A hash table of path-inidices that are contributing flags to this interface.
+     * Since paths with next-hops can be on the same interface and each of those
+     * paths can contribute different flags, we need to maintain the flag
+     * contribution from each path, and use a combination for forwarding.
+     */
+    uword *mfi_hash;
 } mfib_itf_t;
 
+/**
+ * update an interface from a path.
+ * returns 1 if the entry is removed, i.e. has no flags left, as a result
+ * of the update.
+ */
+extern int mfib_itf_update(mfib_itf_t *itf,
+                           fib_node_index_t path_index,
+                           mfib_itf_flags_t mfi_flags);
 
-extern index_t mfib_itf_create(u32 sw_if_index,
+extern index_t mfib_itf_create(fib_node_index_t path_index,
                                mfib_itf_flags_t mfi_flags);
-extern void mfib_itf_delete(mfib_itf_t *mfi);
+
+extern void mfib_itf_delete(mfib_itf_t *itf);
 
 extern u8 *format_mfib_itf(u8 * s, va_list * args);
 
 extern mfib_itf_t *mfib_itf_pool;
 
+/**
+ * Get the MFIB interface representation
+ */
 static inline mfib_itf_t *
 mfib_itf_get (index_t mi)
 {
     return (pool_elt_at_index(mfib_itf_pool, mi));
 }
+
 static inline index_t
 mfib_itf_get_index (const mfib_itf_t *mfi)
 {
diff --git a/src/vnet/mfib/mfib_test.c b/src/vnet/mfib/mfib_test.c
index 8c75e349b86..a94b308473e 100644
--- a/src/vnet/mfib/mfib_test.c
+++ b/src/vnet/mfib/mfib_test.c
@@ -347,11 +347,14 @@ mfib_test_i (fib_protocol_t PROTO,
              const mfib_prefix_t *pfx_star_g_1,
              const mfib_prefix_t *pfx_star_g_2,
              const mfib_prefix_t *pfx_star_g_3,
-             const mfib_prefix_t *pfx_star_g_slash_m)
+             const mfib_prefix_t *pfx_star_g_slash_m,
+             const fib_prefix_t *pfx_itf,
+             const ip46_address_t *addr_nbr1,
+             const ip46_address_t *addr_nbr2)
 {
     fib_node_index_t mfei, mfei_dflt, mfei_no_f, mfei_s_g, mfei_g_1, mfei_g_2, mfei_g_3, mfei_g_m;
     u32 fib_index, n_entries, n_itfs, n_reps, n_pls;
-    fib_node_index_t ai_1, ai_2, ai_3;
+    fib_node_index_t ai_1, ai_2, ai_3, ai_nbr1, ai_nbr2;
     test_main_t *tm;
     int res;
 
@@ -374,12 +377,33 @@ mfib_test_i (fib_protocol_t PROTO,
     ai_3 = adj_mcast_add_or_lock(PROTO,
                                  LINKT,
                                  tm->hw[3]->sw_if_index);
+    ai_nbr1 = adj_nbr_add_or_lock(PROTO,
+                                  LINKT,
+                                  addr_nbr1,
+                                  tm->hw[0]->sw_if_index);
+    ai_nbr2 = adj_nbr_add_or_lock(PROTO,
+                                  LINKT,
+                                  addr_nbr2,
+                                  tm->hw[0]->sw_if_index);
 
     MFIB_TEST(3 == adj_mcast_db_size(), "3 MCAST adjs");
 
     /* Find or create FIB table 11 */
     fib_index = mfib_table_find_or_create_and_lock(PROTO, 11, MFIB_SOURCE_API);
 
+    fib_table_entry_update_one_path(0,
+                                    pfx_itf,
+				    FIB_SOURCE_INTERFACE,
+				    (FIB_ENTRY_FLAG_CONNECTED |
+				     FIB_ENTRY_FLAG_ATTACHED),
+				    DPO_PROTO_IP4,
+				    NULL,
+				    tm->hw[0]->sw_if_index,
+				    ~0, // invalid fib index
+				    1, // weight
+				    NULL,
+				    FIB_ROUTE_PATH_FLAG_NONE);
+
     mfib_prefix_t pfx_dft = {
         .fp_len = 0,
         .fp_proto = PROTO,
@@ -1043,6 +1067,69 @@ mfib_test_i (fib_protocol_t PROTO,
               format_mfib_prefix, pfx_star_g_slash_m);
 
     /*
+     * Entries with paths via unicast next-hops
+     */
+    fib_route_path_t path_via_nbr1 = {
+        .frp_proto = fib_proto_to_dpo(PROTO),
+        .frp_addr = *addr_nbr1,
+        .frp_sw_if_index = tm->hw[0]->sw_if_index,
+        .frp_fib_index = ~0,
+        .frp_weight = 0,
+        .frp_flags = 0,
+    };
+    fib_route_path_t path_via_nbr2 = {
+        .frp_proto = fib_proto_to_dpo(PROTO),
+        .frp_addr = *addr_nbr2,
+        .frp_sw_if_index = tm->hw[0]->sw_if_index,
+        .frp_fib_index = ~0,
+        .frp_weight = 0,
+        .frp_flags = 0,
+    };
+
+    mfei_g_1 = mfib_table_entry_path_update(fib_index,
+                                            pfx_star_g_1,
+                                            MFIB_SOURCE_API,
+                                            &path_via_nbr1,
+                                            (MFIB_ITF_FLAG_FORWARD));
+    mfei_g_1 = mfib_table_entry_path_update(fib_index,
+                                            pfx_star_g_1,
+                                            MFIB_SOURCE_API,
+                                            &path_via_nbr2,
+                                            (MFIB_ITF_FLAG_FORWARD));
+    MFIB_TEST(!mfib_test_entry(mfei_g_1,
+                               MFIB_ENTRY_FLAG_NONE,
+                               2,
+                               DPO_ADJACENCY_INCOMPLETE, ai_nbr1,
+                               DPO_ADJACENCY_INCOMPLETE, ai_nbr2),
+              "%U replicate OK",
+              format_mfib_prefix, pfx_star_g_1);
+    MFIB_TEST_NS(!mfib_test_entry_itf(mfei_g_1, tm->hw[0]->sw_if_index,
+                                      MFIB_ITF_FLAG_FORWARD));
+
+    mfib_table_entry_path_remove(fib_index,
+                                 pfx_star_g_1,
+                                 MFIB_SOURCE_API,
+                                 &path_via_nbr1);
+
+    MFIB_TEST(!mfib_test_entry(mfei_g_1,
+                               MFIB_ENTRY_FLAG_NONE,
+                               1,
+                               DPO_ADJACENCY_INCOMPLETE, ai_nbr2),
+              "%U replicate OK",
+              format_mfib_prefix, pfx_star_g_1);
+    MFIB_TEST_NS(!mfib_test_entry_itf(mfei_g_1, tm->hw[0]->sw_if_index,
+                                      MFIB_ITF_FLAG_FORWARD));
+
+    mfib_table_entry_path_remove(fib_index,
+                                 pfx_star_g_1,
+                                 MFIB_SOURCE_API,
+                                 &path_via_nbr2);
+    mfei = mfib_table_lookup_exact_match(fib_index, pfx_star_g_1);
+    MFIB_TEST(FIB_NODE_INDEX_INVALID == mfei,
+              "%U Gone",
+              format_mfib_prefix, pfx_star_g_1);
+
+    /*
      * Add a prefix as a special/exclusive route
      */
     dpo_id_t td = DPO_INVALID;
@@ -1216,6 +1303,8 @@ mfib_test_i (fib_protocol_t PROTO,
     adj_unlock(ai_1);
     adj_unlock(ai_2);
     adj_unlock(ai_3);
+    adj_unlock(ai_nbr1);
+    adj_unlock(ai_nbr2);
 
     /*
      * MPLS disable the interface
@@ -1226,6 +1315,11 @@ mfib_test_i (fib_protocol_t PROTO,
     mpls_table_delete(MPLS_FIB_DEFAULT_TABLE_ID, FIB_SOURCE_API);
 
     /*
+     * remove the connected
+     */
+    fib_table_entry_delete(0, pfx_itf, FIB_SOURCE_INTERFACE);
+
+    /*
      * test we've leaked no resources
      */
     MFIB_TEST(0 == adj_mcast_db_size(), "%d MCAST adjs", adj_mcast_db_size());
@@ -1303,7 +1397,19 @@ mfib_test_v4 (void)
             .ip4.as_u32 = 0,
         },
     };
-
+    const fib_prefix_t pfx_itf = {
+        .fp_len = 24,
+        .fp_proto = FIB_PROTOCOL_IP4,
+        .fp_addr = {
+            .ip4.as_u32 = clib_host_to_net_u32(0x0a0a0a0a),
+        },
+    };
+    const ip46_address_t nbr1 = {
+        .ip4.as_u32 = clib_host_to_net_u32(0x0a0a0a0b),
+    };
+    const ip46_address_t nbr2 = {
+        .ip4.as_u32 = clib_host_to_net_u32(0x0a0a0a0c),
+    };
     return (mfib_test_i(FIB_PROTOCOL_IP4,
                         VNET_LINK_IP4,
                         &pfx_224_s_8,
@@ -1311,7 +1417,10 @@ mfib_test_v4 (void)
                         &pfx_239_1_1_1,
                         &pfx_239_1_1_2,
                         &pfx_239_1_1_3,
-                        &pfx_239));
+                        &pfx_239,
+                        &pfx_itf,
+                        &nbr1,
+                        &nbr2));
 }
 
 static int
@@ -1371,6 +1480,22 @@ mfib_test_v6 (void)
             .ip6.as_u64[1] = clib_host_to_net_u64(0x0000000000000000),
         },
     };
+    const fib_prefix_t pfx_itf = {
+        .fp_len = 64,
+        .fp_proto = FIB_PROTOCOL_IP6,
+        .fp_addr = {
+            .ip6.as_u64[0] = clib_host_to_net_u64(0x2001000000000000),
+            .ip6.as_u64[1] = clib_host_to_net_u64(0x0000000000000001),
+        },
+    };
+    const ip46_address_t nbr1 = {
+            .ip6.as_u64[0] = clib_host_to_net_u64(0x2001000000000000),
+            .ip6.as_u64[1] = clib_host_to_net_u64(0x0000000000000002),
+    };
+    const ip46_address_t nbr2 = {
+            .ip6.as_u64[0] = clib_host_to_net_u64(0x2001000000000000),
+            .ip6.as_u64[1] = clib_host_to_net_u64(0x0000000000000003),
+    };
 
     return (mfib_test_i(FIB_PROTOCOL_IP6,
                         VNET_LINK_IP6,
@@ -1379,7 +1504,10 @@ mfib_test_v6 (void)
                         &pfx_ff_1,
                         &pfx_ff_2,
                         &pfx_ff_3,
-                        &pfx_ff));
+                        &pfx_ff,
+                        &pfx_itf,
+                        &nbr1,
+                        &nbr2));
 }
 
 static clib_error_t *
@@ -1391,6 +1519,12 @@ mfib_test (vlib_main_t * vm,
 
     res += mfib_test_mk_intf(4);
     res += mfib_test_v4();
+
+    if (res)
+    {
+        return clib_error_return(0, "MFIB Unit Test Failed");
+    }
+
     res += mfib_test_v6();
 
     if (res)