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-rw-r--r--src/vnet/fib/fib_path.c2001
1 files changed, 2001 insertions, 0 deletions
diff --git a/src/vnet/fib/fib_path.c b/src/vnet/fib/fib_path.c
new file mode 100644
index 00000000000..809e3e166da
--- /dev/null
+++ b/src/vnet/fib/fib_path.c
@@ -0,0 +1,2001 @@
+/*
+ * 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 <vlib/vlib.h>
+#include <vnet/vnet.h>
+#include <vnet/ip/format.h>
+#include <vnet/ip/ip.h>
+#include <vnet/dpo/drop_dpo.h>
+#include <vnet/dpo/receive_dpo.h>
+#include <vnet/dpo/load_balance_map.h>
+#include <vnet/dpo/lookup_dpo.h>
+
+#include <vnet/adj/adj.h>
+
+#include <vnet/fib/fib_path.h>
+#include <vnet/fib/fib_node.h>
+#include <vnet/fib/fib_table.h>
+#include <vnet/fib/fib_entry.h>
+#include <vnet/fib/fib_path_list.h>
+#include <vnet/fib/fib_internal.h>
+#include <vnet/fib/fib_urpf_list.h>
+
+/**
+ * Enurmeration of path types
+ */
+typedef enum fib_path_type_t_ {
+ /**
+ * Marker. Add new types after this one.
+ */
+ FIB_PATH_TYPE_FIRST = 0,
+ /**
+ * Attached-nexthop. An interface and a nexthop are known.
+ */
+ FIB_PATH_TYPE_ATTACHED_NEXT_HOP = FIB_PATH_TYPE_FIRST,
+ /**
+ * attached. Only the interface is known.
+ */
+ FIB_PATH_TYPE_ATTACHED,
+ /**
+ * recursive. Only the next-hop is known.
+ */
+ FIB_PATH_TYPE_RECURSIVE,
+ /**
+ * special. nothing is known. so we drop.
+ */
+ FIB_PATH_TYPE_SPECIAL,
+ /**
+ * exclusive. user provided adj.
+ */
+ FIB_PATH_TYPE_EXCLUSIVE,
+ /**
+ * deag. Link to a lookup adj in the next table
+ */
+ FIB_PATH_TYPE_DEAG,
+ /**
+ * receive. it's for-us.
+ */
+ FIB_PATH_TYPE_RECEIVE,
+ /**
+ * Marker. Add new types before this one, then update it.
+ */
+ FIB_PATH_TYPE_LAST = FIB_PATH_TYPE_RECEIVE,
+} __attribute__ ((packed)) fib_path_type_t;
+
+/**
+ * The maximum number of path_types
+ */
+#define FIB_PATH_TYPE_MAX (FIB_PATH_TYPE_LAST + 1)
+
+#define FIB_PATH_TYPES { \
+ [FIB_PATH_TYPE_ATTACHED_NEXT_HOP] = "attached-nexthop", \
+ [FIB_PATH_TYPE_ATTACHED] = "attached", \
+ [FIB_PATH_TYPE_RECURSIVE] = "recursive", \
+ [FIB_PATH_TYPE_SPECIAL] = "special", \
+ [FIB_PATH_TYPE_EXCLUSIVE] = "exclusive", \
+ [FIB_PATH_TYPE_DEAG] = "deag", \
+ [FIB_PATH_TYPE_RECEIVE] = "receive", \
+}
+
+#define FOR_EACH_FIB_PATH_TYPE(_item) \
+ for (_item = FIB_PATH_TYPE_FIRST; _item <= FIB_PATH_TYPE_LAST; _item++)
+
+/**
+ * Enurmeration of path operational (i.e. derived) attributes
+ */
+typedef enum fib_path_oper_attribute_t_ {
+ /**
+ * Marker. Add new types after this one.
+ */
+ FIB_PATH_OPER_ATTRIBUTE_FIRST = 0,
+ /**
+ * The path forms part of a recursive loop.
+ */
+ FIB_PATH_OPER_ATTRIBUTE_RECURSIVE_LOOP = FIB_PATH_OPER_ATTRIBUTE_FIRST,
+ /**
+ * The path is resolved
+ */
+ FIB_PATH_OPER_ATTRIBUTE_RESOLVED,
+ /**
+ * The path has become a permanent drop.
+ */
+ FIB_PATH_OPER_ATTRIBUTE_DROP,
+ /**
+ * Marker. Add new types before this one, then update it.
+ */
+ FIB_PATH_OPER_ATTRIBUTE_LAST = FIB_PATH_OPER_ATTRIBUTE_DROP,
+} __attribute__ ((packed)) fib_path_oper_attribute_t;
+
+/**
+ * The maximum number of path operational attributes
+ */
+#define FIB_PATH_OPER_ATTRIBUTE_MAX (FIB_PATH_OPER_ATTRIBUTE_LAST + 1)
+
+#define FIB_PATH_OPER_ATTRIBUTES { \
+ [FIB_PATH_OPER_ATTRIBUTE_RECURSIVE_LOOP] = "recursive-loop", \
+ [FIB_PATH_OPER_ATTRIBUTE_RESOLVED] = "resolved", \
+ [FIB_PATH_OPER_ATTRIBUTE_DROP] = "drop", \
+}
+
+#define FOR_EACH_FIB_PATH_OPER_ATTRIBUTE(_item) \
+ for (_item = FIB_PATH_OPER_ATTRIBUTE_FIRST; \
+ _item <= FIB_PATH_OPER_ATTRIBUTE_LAST; \
+ _item++)
+
+/**
+ * Path flags from the attributes
+ */
+typedef enum fib_path_oper_flags_t_ {
+ FIB_PATH_OPER_FLAG_NONE = 0,
+ FIB_PATH_OPER_FLAG_RECURSIVE_LOOP = (1 << FIB_PATH_OPER_ATTRIBUTE_RECURSIVE_LOOP),
+ FIB_PATH_OPER_FLAG_DROP = (1 << FIB_PATH_OPER_ATTRIBUTE_DROP),
+ FIB_PATH_OPER_FLAG_RESOLVED = (1 << FIB_PATH_OPER_ATTRIBUTE_RESOLVED),
+} __attribute__ ((packed)) fib_path_oper_flags_t;
+
+/**
+ * A FIB path
+ */
+typedef struct fib_path_t_ {
+ /**
+ * A path is a node in the FIB graph.
+ */
+ fib_node_t fp_node;
+
+ /**
+ * The index of the path-list to which this path belongs
+ */
+ u32 fp_pl_index;
+
+ /**
+ * This marks the start of the memory area used to hash
+ * the path
+ */
+ STRUCT_MARK(path_hash_start);
+
+ /**
+ * Configuration Flags
+ */
+ fib_path_cfg_flags_t fp_cfg_flags;
+
+ /**
+ * The type of the path. This is the selector for the union
+ */
+ fib_path_type_t fp_type;
+
+ /**
+ * The protocol of the next-hop, i.e. the address family of the
+ * next-hop's address. We can't derive this from the address itself
+ * since the address can be all zeros
+ */
+ fib_protocol_t fp_nh_proto;
+
+ /**
+ * UCMP [unnormalised] weigt
+ */
+ u32 fp_weight;
+
+ /**
+ * per-type union of the data required to resolve the path
+ */
+ union {
+ struct {
+ /**
+ * The next-hop
+ */
+ ip46_address_t fp_nh;
+ /**
+ * The interface
+ */
+ u32 fp_interface;
+ } attached_next_hop;
+ struct {
+ /**
+ * The interface
+ */
+ u32 fp_interface;
+ } attached;
+ struct {
+ union
+ {
+ /**
+ * The next-hop
+ */
+ ip46_address_t fp_ip;
+ /**
+ * The local label to resolve through.
+ */
+ mpls_label_t fp_local_label;
+ } fp_nh;
+ /**
+ * The FIB table index in which to find the next-hop.
+ * This needs to be fixed. We should lookup the adjacencies in
+ * a separate table of adjacencies, rather than from the FIB.
+ * Two reasons I can think of:
+ * - consider:
+ * int ip addr Gig0 10.0.0.1/24
+ * ip route 10.0.0.2/32 via Gig1 192.168.1.2
+ * ip route 1.1.1.1/32 via Gig0 10.0.0.2
+ * this is perfectly valid.
+ * Packets addressed to 10.0.0.2 should be sent via Gig1.
+ * Packets address to 1.1.1.1 should be sent via Gig0.
+ * when we perform the adj resolution from the FIB for the path
+ * "via Gig0 10.0.0.2" the lookup will result in the route via Gig1
+ * and so we will pick up the adj via Gig1 - which was not what the
+ * operator wanted.
+ * - we can only return link-type IPv4 and so not the link-type MPLS.
+ * more on this in a later commit.
+ *
+ * The table ID should only belong to a recursive path and indicate
+ * which FIB should be used to resolve the next-hop.
+ */
+ fib_node_index_t fp_tbl_id;
+ } recursive;
+ struct {
+ /**
+ * The FIB index in which to perfom the next lookup
+ */
+ fib_node_index_t fp_tbl_id;
+ } deag;
+ struct {
+ } special;
+ struct {
+ /**
+ * The user provided 'exclusive' DPO
+ */
+ dpo_id_t fp_ex_dpo;
+ } exclusive;
+ struct {
+ /**
+ * The interface on which the local address is configured
+ */
+ u32 fp_interface;
+ /**
+ * The next-hop
+ */
+ ip46_address_t fp_addr;
+ } receive;
+ };
+ STRUCT_MARK(path_hash_end);
+
+ /**
+ * Memebers in this last section represent information that is
+ * dervied during resolution. It should not be copied to new paths
+ * nor compared.
+ */
+
+ /**
+ * Operational Flags
+ */
+ fib_path_oper_flags_t fp_oper_flags;
+
+ /**
+ * the resolving via fib. not part of the union, since it it not part
+ * of the path's hash.
+ */
+ fib_node_index_t fp_via_fib;
+
+ /**
+ * The Data-path objects through which this path resolves for IP.
+ */
+ dpo_id_t fp_dpo;
+
+ /**
+ * the index of this path in the parent's child list.
+ */
+ u32 fp_sibling;
+} fib_path_t;
+
+/*
+ * Array of strings/names for the path types and attributes
+ */
+static const char *fib_path_type_names[] = FIB_PATH_TYPES;
+static const char *fib_path_oper_attribute_names[] = FIB_PATH_OPER_ATTRIBUTES;
+static const char *fib_path_cfg_attribute_names[] = FIB_PATH_CFG_ATTRIBUTES;
+
+/*
+ * The memory pool from which we allocate all the paths
+ */
+static fib_path_t *fib_path_pool;
+
+/*
+ * Debug macro
+ */
+#ifdef FIB_DEBUG
+#define FIB_PATH_DBG(_p, _fmt, _args...) \
+{ \
+ u8 *_tmp = NULL; \
+ _tmp = fib_path_format(fib_path_get_index(_p), _tmp); \
+ clib_warning("path:[%d:%s]:" _fmt, \
+ fib_path_get_index(_p), _tmp, \
+ ##_args); \
+ vec_free(_tmp); \
+}
+#else
+#define FIB_PATH_DBG(_p, _fmt, _args...)
+#endif
+
+static fib_path_t *
+fib_path_get (fib_node_index_t index)
+{
+ return (pool_elt_at_index(fib_path_pool, index));
+}
+
+static fib_node_index_t
+fib_path_get_index (fib_path_t *path)
+{
+ return (path - fib_path_pool);
+}
+
+static fib_node_t *
+fib_path_get_node (fib_node_index_t index)
+{
+ return ((fib_node_t*)fib_path_get(index));
+}
+
+static fib_path_t*
+fib_path_from_fib_node (fib_node_t *node)
+{
+#if CLIB_DEBUG > 0
+ ASSERT(FIB_NODE_TYPE_PATH == node->fn_type);
+#endif
+ return ((fib_path_t*)node);
+}
+
+u8 *
+format_fib_path (u8 * s, va_list * args)
+{
+ fib_path_t *path = va_arg (*args, fib_path_t *);
+ vnet_main_t * vnm = vnet_get_main();
+ fib_path_oper_attribute_t oattr;
+ fib_path_cfg_attribute_t cattr;
+
+ s = format (s, " index:%d ", fib_path_get_index(path));
+ s = format (s, "pl-index:%d ", path->fp_pl_index);
+ s = format (s, "%U ", format_fib_protocol, path->fp_nh_proto);
+ s = format (s, "weight=%d ", path->fp_weight);
+ s = format (s, "%s: ", fib_path_type_names[path->fp_type]);
+ if (FIB_PATH_OPER_FLAG_NONE != path->fp_oper_flags) {
+ s = format(s, " oper-flags:");
+ FOR_EACH_FIB_PATH_OPER_ATTRIBUTE(oattr) {
+ if ((1<<oattr) & path->fp_oper_flags) {
+ s = format (s, "%s,", fib_path_oper_attribute_names[oattr]);
+ }
+ }
+ }
+ if (FIB_PATH_CFG_FLAG_NONE != path->fp_cfg_flags) {
+ s = format(s, " cfg-flags:");
+ FOR_EACH_FIB_PATH_CFG_ATTRIBUTE(cattr) {
+ if ((1<<cattr) & path->fp_cfg_flags) {
+ s = format (s, "%s,", fib_path_cfg_attribute_names[cattr]);
+ }
+ }
+ }
+ s = format(s, "\n ");
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ s = format (s, "%U", format_ip46_address,
+ &path->attached_next_hop.fp_nh,
+ IP46_TYPE_ANY);
+ if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_DROP)
+ {
+ s = format (s, " if_index:%d", path->attached_next_hop.fp_interface);
+ }
+ else
+ {
+ s = format (s, " %U",
+ format_vnet_sw_interface_name,
+ vnm,
+ vnet_get_sw_interface(
+ vnm,
+ path->attached_next_hop.fp_interface));
+ if (vnet_sw_interface_is_p2p(vnet_get_main(),
+ path->attached_next_hop.fp_interface))
+ {
+ s = format (s, " (p2p)");
+ }
+ }
+ if (!dpo_id_is_valid(&path->fp_dpo))
+ {
+ s = format(s, "\n unresolved");
+ }
+ else
+ {
+ s = format(s, "\n %U",
+ format_dpo_id,
+ &path->fp_dpo, 13);
+ }
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_DROP)
+ {
+ s = format (s, " if_index:%d", path->attached_next_hop.fp_interface);
+ }
+ else
+ {
+ s = format (s, " %U",
+ format_vnet_sw_interface_name,
+ vnm,
+ vnet_get_sw_interface(
+ vnm,
+ path->attached.fp_interface));
+ }
+ break;
+ case FIB_PATH_TYPE_RECURSIVE:
+ if (FIB_PROTOCOL_MPLS == path->fp_nh_proto)
+ {
+ s = format (s, "via %U",
+ format_mpls_unicast_label,
+ path->recursive.fp_nh.fp_local_label);
+ }
+ else
+ {
+ s = format (s, "via %U",
+ format_ip46_address,
+ &path->recursive.fp_nh.fp_ip,
+ IP46_TYPE_ANY);
+ }
+ s = format (s, " in fib:%d",
+ path->recursive.fp_tbl_id,
+ path->fp_via_fib);
+ s = format (s, " via-fib:%d", path->fp_via_fib);
+ s = format (s, " via-dpo:[%U:%d]",
+ format_dpo_type, path->fp_dpo.dpoi_type,
+ path->fp_dpo.dpoi_index);
+
+ break;
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_DEAG:
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ if (dpo_id_is_valid(&path->fp_dpo))
+ {
+ s = format(s, "%U", format_dpo_id,
+ &path->fp_dpo, 2);
+ }
+ break;
+ }
+ return (s);
+}
+
+u8 *
+fib_path_format (fib_node_index_t pi, u8 *s)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(pi);
+ ASSERT(NULL != path);
+
+ return (format (s, "%U", format_fib_path, path));
+}
+
+u8 *
+fib_path_adj_format (fib_node_index_t pi,
+ u32 indent,
+ u8 *s)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(pi);
+ ASSERT(NULL != path);
+
+ if (!dpo_id_is_valid(&path->fp_dpo))
+ {
+ s = format(s, " unresolved");
+ }
+ else
+ {
+ s = format(s, "%U", format_dpo_id,
+ &path->fp_dpo, 2);
+ }
+
+ return (s);
+}
+
+/*
+ * fib_path_last_lock_gone
+ *
+ * We don't share paths, we share path lists, so the [un]lock functions
+ * are no-ops
+ */
+static void
+fib_path_last_lock_gone (fib_node_t *node)
+{
+ ASSERT(0);
+}
+
+static const adj_index_t
+fib_path_attached_next_hop_get_adj (fib_path_t *path,
+ vnet_link_t link)
+{
+ if (vnet_sw_interface_is_p2p(vnet_get_main(),
+ path->attached_next_hop.fp_interface))
+ {
+ /*
+ * if the interface is p2p then the adj for the specific
+ * neighbour on that link will never exist. on p2p links
+ * the subnet address (the attached route) links to the
+ * auto-adj (see below), we want that adj here too.
+ */
+ return (adj_nbr_add_or_lock(path->fp_nh_proto,
+ link,
+ &zero_addr,
+ path->attached_next_hop.fp_interface));
+ }
+ else
+ {
+ return (adj_nbr_add_or_lock(path->fp_nh_proto,
+ link,
+ &path->attached_next_hop.fp_nh,
+ path->attached_next_hop.fp_interface));
+ }
+}
+
+static void
+fib_path_attached_next_hop_set (fib_path_t *path)
+{
+ /*
+ * resolve directly via the adjacnecy discribed by the
+ * interface and next-hop
+ */
+ if (!vnet_sw_interface_is_admin_up(vnet_get_main(),
+ path->attached_next_hop.fp_interface))
+ {
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+
+ dpo_set(&path->fp_dpo,
+ DPO_ADJACENCY,
+ fib_proto_to_dpo(path->fp_nh_proto),
+ fib_path_attached_next_hop_get_adj(
+ path,
+ fib_proto_to_link(path->fp_nh_proto)));
+
+ /*
+ * become a child of the adjacency so we receive updates
+ * when its rewrite changes
+ */
+ path->fp_sibling = adj_child_add(path->fp_dpo.dpoi_index,
+ FIB_NODE_TYPE_PATH,
+ fib_path_get_index(path));
+}
+
+/*
+ * create of update the paths recursive adj
+ */
+static void
+fib_path_recursive_adj_update (fib_path_t *path,
+ fib_forward_chain_type_t fct,
+ dpo_id_t *dpo)
+{
+ dpo_id_t via_dpo = DPO_INVALID;
+
+ /*
+ * get the DPO to resolve through from the via-entry
+ */
+ fib_entry_contribute_forwarding(path->fp_via_fib,
+ fct,
+ &via_dpo);
+
+
+ /*
+ * hope for the best - clear if restrictions apply.
+ */
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
+
+ /*
+ * Validate any recursion constraints and over-ride the via
+ * adj if not met
+ */
+ if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RECURSIVE_LOOP)
+ {
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ dpo_copy(&via_dpo, drop_dpo_get(fib_proto_to_dpo(path->fp_nh_proto)));
+ }
+ else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_HOST)
+ {
+ /*
+ * the via FIB must be a host route.
+ * note the via FIB just added will always be a host route
+ * since it is an RR source added host route. So what we need to
+ * check is whether the route has other sources. If it does then
+ * some other source has added it as a host route. If it doesn't
+ * then it was added only here and inherits forwarding from a cover.
+ * the cover is not a host route.
+ * The RR source is the lowest priority source, so we check if it
+ * is the best. if it is there are no other sources.
+ */
+ if (fib_entry_get_best_source(path->fp_via_fib) >= FIB_SOURCE_RR)
+ {
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ dpo_copy(&via_dpo, drop_dpo_get(fib_proto_to_dpo(path->fp_nh_proto)));
+
+ /*
+ * PIC edge trigger. let the load-balance maps know
+ */
+ load_balance_map_path_state_change(fib_path_get_index(path));
+ }
+ }
+ else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED)
+ {
+ /*
+ * RR source entries inherit the flags from the cover, so
+ * we can check the via directly
+ */
+ if (!(FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags(path->fp_via_fib)))
+ {
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ dpo_copy(&via_dpo, drop_dpo_get(fib_proto_to_dpo(path->fp_nh_proto)));
+
+ /*
+ * PIC edge trigger. let the load-balance maps know
+ */
+ load_balance_map_path_state_change(fib_path_get_index(path));
+ }
+ }
+
+ /*
+ * update the path's contributed DPO
+ */
+ dpo_copy(dpo, &via_dpo);
+
+ FIB_PATH_DBG(path, "recursive update: %U",
+ fib_get_lookup_main(path->fp_nh_proto),
+ &path->fp_dpo, 2);
+
+ dpo_reset(&via_dpo);
+}
+
+/*
+ * fib_path_is_permanent_drop
+ *
+ * Return !0 if the path is configured to permanently drop,
+ * despite other attributes.
+ */
+static int
+fib_path_is_permanent_drop (fib_path_t *path)
+{
+ return ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_DROP) ||
+ (path->fp_oper_flags & FIB_PATH_OPER_FLAG_DROP));
+}
+
+/*
+ * fib_path_unresolve
+ *
+ * Remove our dependency on the resolution target
+ */
+static void
+fib_path_unresolve (fib_path_t *path)
+{
+ /*
+ * the forced drop path does not need unresolving
+ */
+ if (fib_path_is_permanent_drop(path))
+ {
+ return;
+ }
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_RECURSIVE:
+ if (FIB_NODE_INDEX_INVALID != path->fp_via_fib)
+ {
+ fib_prefix_t pfx;
+
+ fib_entry_get_prefix(path->fp_via_fib, &pfx);
+ fib_entry_child_remove(path->fp_via_fib,
+ path->fp_sibling);
+ fib_table_entry_special_remove(path->recursive.fp_tbl_id,
+ &pfx,
+ FIB_SOURCE_RR);
+ path->fp_via_fib = FIB_NODE_INDEX_INVALID;
+ }
+ break;
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ case FIB_PATH_TYPE_ATTACHED:
+ adj_child_remove(path->fp_dpo.dpoi_index,
+ path->fp_sibling);
+ adj_unlock(path->fp_dpo.dpoi_index);
+ break;
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ dpo_reset(&path->exclusive.fp_ex_dpo);
+ break;
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_DEAG:
+ /*
+ * these hold only the path's DPO, which is reset below.
+ */
+ break;
+ }
+
+ /*
+ * release the adj we were holding and pick up the
+ * drop just in case.
+ */
+ dpo_reset(&path->fp_dpo);
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+
+ return;
+}
+
+static fib_forward_chain_type_t
+fib_path_proto_to_chain_type (fib_protocol_t proto)
+{
+ switch (proto)
+ {
+ case FIB_PROTOCOL_IP4:
+ return (FIB_FORW_CHAIN_TYPE_UNICAST_IP4);
+ case FIB_PROTOCOL_IP6:
+ return (FIB_FORW_CHAIN_TYPE_UNICAST_IP6);
+ case FIB_PROTOCOL_MPLS:
+ return (FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS);
+ }
+ return (FIB_FORW_CHAIN_TYPE_UNICAST_IP4);
+}
+
+/*
+ * fib_path_back_walk_notify
+ *
+ * A back walk has reach this path.
+ */
+static fib_node_back_walk_rc_t
+fib_path_back_walk_notify (fib_node_t *node,
+ fib_node_back_walk_ctx_t *ctx)
+{
+ fib_path_t *path;
+
+ path = fib_path_from_fib_node(node);
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_RECURSIVE:
+ if (FIB_NODE_BW_REASON_FLAG_EVALUATE & ctx->fnbw_reason)
+ {
+ /*
+ * modify the recursive adjacency to use the new forwarding
+ * of the via-fib.
+ * this update is visible to packets in flight in the DP.
+ */
+ fib_path_recursive_adj_update(
+ path,
+ fib_path_proto_to_chain_type(path->fp_nh_proto),
+ &path->fp_dpo);
+ }
+ if ((FIB_NODE_BW_REASON_FLAG_ADJ_UPDATE & ctx->fnbw_reason) ||
+ (FIB_NODE_BW_REASON_FLAG_ADJ_DOWN & ctx->fnbw_reason))
+ {
+ /*
+ * ADJ updates (complete<->incomplete) do not need to propagate to
+ * recursive entries.
+ * The only reason its needed as far back as here, is that the adj
+ * and the incomplete adj are a different DPO type, so the LBs need
+ * to re-stack.
+ * If this walk was quashed in the fib_entry, then any non-fib_path
+ * children (like tunnels that collapse out the LB when they stack)
+ * would not see the update.
+ */
+ return (FIB_NODE_BACK_WALK_CONTINUE);
+ }
+ break;
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ /*
+FIXME comment
+ * ADJ_UPDATE backwalk pass silently through here and up to
+ * the path-list when the multipath adj collapse occurs.
+ * The reason we do this is that the assumtption is that VPP
+ * runs in an environment where the Control-Plane is remote
+ * and hence reacts slowly to link up down. In order to remove
+ * this down link from the ECMP set quickly, we back-walk.
+ * VPP also has dedicated CPUs, so we are not stealing resources
+ * from the CP to do so.
+ */
+ if (FIB_NODE_BW_REASON_FLAG_INTERFACE_UP & ctx->fnbw_reason)
+ {
+ if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED)
+ {
+ /*
+ * alreday resolved. no need to walk back again
+ */
+ return (FIB_NODE_BACK_WALK_CONTINUE);
+ }
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+ if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DOWN & ctx->fnbw_reason)
+ {
+ if (!(path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED))
+ {
+ /*
+ * alreday unresolved. no need to walk back again
+ */
+ return (FIB_NODE_BACK_WALK_CONTINUE);
+ }
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+ if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DELETE & ctx->fnbw_reason)
+ {
+ /*
+ * The interface this path resolves through has been deleted.
+ * This will leave the path in a permanent drop state. The route
+ * needs to be removed and readded (and hence the path-list deleted)
+ * before it can forward again.
+ */
+ fib_path_unresolve(path);
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_DROP;
+ }
+ if (FIB_NODE_BW_REASON_FLAG_ADJ_UPDATE & ctx->fnbw_reason)
+ {
+ /*
+ * restack the DPO to pick up the correct DPO sub-type
+ */
+ uword if_is_up;
+ adj_index_t ai;
+
+ if_is_up = vnet_sw_interface_is_admin_up(
+ vnet_get_main(),
+ path->attached_next_hop.fp_interface);
+
+ if (if_is_up)
+ {
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+
+ ai = fib_path_attached_next_hop_get_adj(
+ path,
+ fib_proto_to_link(path->fp_nh_proto));
+
+ dpo_set(&path->fp_dpo, DPO_ADJACENCY,
+ fib_proto_to_dpo(path->fp_nh_proto),
+ ai);
+ adj_unlock(ai);
+
+ if (!if_is_up)
+ {
+ /*
+ * If the interface is not up there is no reason to walk
+ * back to children. if we did they would only evalute
+ * that this path is unresolved and hence it would
+ * not contribute the adjacency - so it would be wasted
+ * CPU time.
+ */
+ return (FIB_NODE_BACK_WALK_CONTINUE);
+ }
+ }
+ if (FIB_NODE_BW_REASON_FLAG_ADJ_DOWN & ctx->fnbw_reason)
+ {
+ if (!(path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED))
+ {
+ /*
+ * alreday unresolved. no need to walk back again
+ */
+ return (FIB_NODE_BACK_WALK_CONTINUE);
+ }
+ /*
+ * the adj has gone down. the path is no longer resolved.
+ */
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ /*
+ * FIXME; this could schedule a lower priority walk, since attached
+ * routes are not usually in ECMP configurations so the backwalk to
+ * the FIB entry does not need to be high priority
+ */
+ if (FIB_NODE_BW_REASON_FLAG_INTERFACE_UP & ctx->fnbw_reason)
+ {
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+ if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DOWN & ctx->fnbw_reason)
+ {
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+ if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DELETE & ctx->fnbw_reason)
+ {
+ fib_path_unresolve(path);
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_DROP;
+ }
+ break;
+ case FIB_PATH_TYPE_DEAG:
+ /*
+ * FIXME When VRF delete is allowed this will need a poke.
+ */
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ /*
+ * these path types have no parents. so to be
+ * walked from one is unexpected.
+ */
+ ASSERT(0);
+ break;
+ }
+
+ /*
+ * propagate the backwalk further to the path-list
+ */
+ fib_path_list_back_walk(path->fp_pl_index, ctx);
+
+ return (FIB_NODE_BACK_WALK_CONTINUE);
+}
+
+static void
+fib_path_memory_show (void)
+{
+ fib_show_memory_usage("Path",
+ pool_elts(fib_path_pool),
+ pool_len(fib_path_pool),
+ sizeof(fib_path_t));
+}
+
+/*
+ * The FIB path's graph node virtual function table
+ */
+static const fib_node_vft_t fib_path_vft = {
+ .fnv_get = fib_path_get_node,
+ .fnv_last_lock = fib_path_last_lock_gone,
+ .fnv_back_walk = fib_path_back_walk_notify,
+ .fnv_mem_show = fib_path_memory_show,
+};
+
+static fib_path_cfg_flags_t
+fib_path_route_flags_to_cfg_flags (const fib_route_path_t *rpath)
+{
+ fib_path_cfg_flags_t cfg_flags = FIB_PATH_CFG_FLAG_NONE;
+
+ if (rpath->frp_flags & FIB_ROUTE_PATH_RESOLVE_VIA_HOST)
+ cfg_flags |= FIB_PATH_CFG_FLAG_RESOLVE_HOST;
+ if (rpath->frp_flags & FIB_ROUTE_PATH_RESOLVE_VIA_ATTACHED)
+ cfg_flags |= FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED;
+
+ return (cfg_flags);
+}
+
+/*
+ * fib_path_create
+ *
+ * Create and initialise a new path object.
+ * return the index of the path.
+ */
+fib_node_index_t
+fib_path_create (fib_node_index_t pl_index,
+ fib_protocol_t nh_proto,
+ fib_path_cfg_flags_t flags,
+ const fib_route_path_t *rpath)
+{
+ fib_path_t *path;
+
+ pool_get(fib_path_pool, path);
+ memset(path, 0, sizeof(*path));
+
+ fib_node_init(&path->fp_node,
+ FIB_NODE_TYPE_PATH);
+
+ dpo_reset(&path->fp_dpo);
+ path->fp_pl_index = pl_index;
+ path->fp_nh_proto = nh_proto;
+ path->fp_via_fib = FIB_NODE_INDEX_INVALID;
+ path->fp_weight = rpath->frp_weight;
+ if (0 == path->fp_weight)
+ {
+ /*
+ * a weight of 0 is a meaningless value. We could either reject it, and thus force
+ * clients to always use 1, or we can accept it and fixup approrpiately.
+ */
+ path->fp_weight = 1;
+ }
+ path->fp_cfg_flags = flags;
+ path->fp_cfg_flags |= fib_path_route_flags_to_cfg_flags(rpath);
+
+ /*
+ * deduce the path's tpye from the parementers and save what is needed.
+ */
+ if (~0 != rpath->frp_sw_if_index)
+ {
+ if (flags & FIB_PATH_CFG_FLAG_LOCAL)
+ {
+ path->fp_type = FIB_PATH_TYPE_RECEIVE;
+ path->receive.fp_interface = rpath->frp_sw_if_index;
+ path->receive.fp_addr = rpath->frp_addr;
+ }
+ else
+ {
+ if (ip46_address_is_zero(&rpath->frp_addr))
+ {
+ path->fp_type = FIB_PATH_TYPE_ATTACHED;
+ path->attached.fp_interface = rpath->frp_sw_if_index;
+ }
+ else
+ {
+ path->fp_type = FIB_PATH_TYPE_ATTACHED_NEXT_HOP;
+ path->attached_next_hop.fp_interface = rpath->frp_sw_if_index;
+ path->attached_next_hop.fp_nh = rpath->frp_addr;
+ }
+ }
+ }
+ else
+ {
+ if (ip46_address_is_zero(&rpath->frp_addr))
+ {
+ if (~0 == rpath->frp_fib_index)
+ {
+ path->fp_type = FIB_PATH_TYPE_SPECIAL;
+ }
+ else
+ {
+ path->fp_type = FIB_PATH_TYPE_DEAG;
+ path->deag.fp_tbl_id = rpath->frp_fib_index;
+ }
+ }
+ else
+ {
+ path->fp_type = FIB_PATH_TYPE_RECURSIVE;
+ if (FIB_PROTOCOL_MPLS == path->fp_nh_proto)
+ {
+ path->recursive.fp_nh.fp_local_label = rpath->frp_local_label;
+ }
+ else
+ {
+ path->recursive.fp_nh.fp_ip = rpath->frp_addr;
+ }
+ path->recursive.fp_tbl_id = rpath->frp_fib_index;
+ }
+ }
+
+ FIB_PATH_DBG(path, "create");
+
+ return (fib_path_get_index(path));
+}
+
+/*
+ * fib_path_create_special
+ *
+ * Create and initialise a new path object.
+ * return the index of the path.
+ */
+fib_node_index_t
+fib_path_create_special (fib_node_index_t pl_index,
+ fib_protocol_t nh_proto,
+ fib_path_cfg_flags_t flags,
+ const dpo_id_t *dpo)
+{
+ fib_path_t *path;
+
+ pool_get(fib_path_pool, path);
+ memset(path, 0, sizeof(*path));
+
+ fib_node_init(&path->fp_node,
+ FIB_NODE_TYPE_PATH);
+ dpo_reset(&path->fp_dpo);
+
+ path->fp_pl_index = pl_index;
+ path->fp_weight = 1;
+ path->fp_nh_proto = nh_proto;
+ path->fp_via_fib = FIB_NODE_INDEX_INVALID;
+ path->fp_cfg_flags = flags;
+
+ if (FIB_PATH_CFG_FLAG_DROP & flags)
+ {
+ path->fp_type = FIB_PATH_TYPE_SPECIAL;
+ }
+ else if (FIB_PATH_CFG_FLAG_LOCAL & flags)
+ {
+ path->fp_type = FIB_PATH_TYPE_RECEIVE;
+ path->attached.fp_interface = FIB_NODE_INDEX_INVALID;
+ }
+ else
+ {
+ path->fp_type = FIB_PATH_TYPE_EXCLUSIVE;
+ ASSERT(NULL != dpo);
+ dpo_copy(&path->exclusive.fp_ex_dpo, dpo);
+ }
+
+ return (fib_path_get_index(path));
+}
+
+/*
+ * fib_path_copy
+ *
+ * Copy a path. return index of new path.
+ */
+fib_node_index_t
+fib_path_copy (fib_node_index_t path_index,
+ fib_node_index_t path_list_index)
+{
+ fib_path_t *path, *orig_path;
+
+ pool_get(fib_path_pool, path);
+
+ orig_path = fib_path_get(path_index);
+ ASSERT(NULL != orig_path);
+
+ memcpy(path, orig_path, sizeof(*path));
+
+ FIB_PATH_DBG(path, "create-copy:%d", path_index);
+
+ /*
+ * reset the dynamic section
+ */
+ fib_node_init(&path->fp_node, FIB_NODE_TYPE_PATH);
+ path->fp_oper_flags = FIB_PATH_OPER_FLAG_NONE;
+ path->fp_pl_index = path_list_index;
+ path->fp_via_fib = FIB_NODE_INDEX_INVALID;
+ memset(&path->fp_dpo, 0, sizeof(path->fp_dpo));
+ dpo_reset(&path->fp_dpo);
+
+ return (fib_path_get_index(path));
+}
+
+/*
+ * fib_path_destroy
+ *
+ * destroy a path that is no longer required
+ */
+void
+fib_path_destroy (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ ASSERT(NULL != path);
+ FIB_PATH_DBG(path, "destroy");
+
+ fib_path_unresolve(path);
+
+ fib_node_deinit(&path->fp_node);
+ pool_put(fib_path_pool, path);
+}
+
+/*
+ * fib_path_destroy
+ *
+ * destroy a path that is no longer required
+ */
+uword
+fib_path_hash (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (hash_memory(STRUCT_MARK_PTR(path, path_hash_start),
+ (STRUCT_OFFSET_OF(fib_path_t, path_hash_end) -
+ STRUCT_OFFSET_OF(fib_path_t, path_hash_start)),
+ 0));
+}
+
+/*
+ * fib_path_cmp_i
+ *
+ * Compare two paths for equivalence.
+ */
+static int
+fib_path_cmp_i (const fib_path_t *path1,
+ const fib_path_t *path2)
+{
+ int res;
+
+ res = 1;
+
+ /*
+ * paths of different types and protocol are not equal.
+ * different weights only are the same path.
+ */
+ if (path1->fp_type != path2->fp_type)
+ {
+ res = (path1->fp_type - path2->fp_type);
+ }
+ if (path1->fp_nh_proto != path2->fp_nh_proto)
+ {
+ res = (path1->fp_nh_proto - path2->fp_nh_proto);
+ }
+ else
+ {
+ /*
+ * both paths are of the same type.
+ * consider each type and its attributes in turn.
+ */
+ switch (path1->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ res = ip46_address_cmp(&path1->attached_next_hop.fp_nh,
+ &path2->attached_next_hop.fp_nh);
+ if (0 == res) {
+ res = vnet_sw_interface_compare(
+ vnet_get_main(),
+ path1->attached_next_hop.fp_interface,
+ path2->attached_next_hop.fp_interface);
+ }
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ res = vnet_sw_interface_compare(
+ vnet_get_main(),
+ path1->attached.fp_interface,
+ path2->attached.fp_interface);
+ break;
+ case FIB_PATH_TYPE_RECURSIVE:
+ res = ip46_address_cmp(&path1->recursive.fp_nh,
+ &path2->recursive.fp_nh);
+
+ if (0 == res)
+ {
+ res = (path1->recursive.fp_tbl_id - path2->recursive.fp_tbl_id);
+ }
+ break;
+ case FIB_PATH_TYPE_DEAG:
+ res = (path1->deag.fp_tbl_id - path2->deag.fp_tbl_id);
+ break;
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ res = 0;
+ break;
+ }
+ }
+ return (res);
+}
+
+/*
+ * fib_path_cmp_for_sort
+ *
+ * Compare two paths for equivalence. Used during path sorting.
+ * As usual 0 means equal.
+ */
+int
+fib_path_cmp_for_sort (void * v1,
+ void * v2)
+{
+ fib_node_index_t *pi1 = v1, *pi2 = v2;
+ fib_path_t *path1, *path2;
+
+ path1 = fib_path_get(*pi1);
+ path2 = fib_path_get(*pi2);
+
+ return (fib_path_cmp_i(path1, path2));
+}
+
+/*
+ * fib_path_cmp
+ *
+ * Compare two paths for equivalence.
+ */
+int
+fib_path_cmp (fib_node_index_t pi1,
+ fib_node_index_t pi2)
+{
+ fib_path_t *path1, *path2;
+
+ path1 = fib_path_get(pi1);
+ path2 = fib_path_get(pi2);
+
+ return (fib_path_cmp_i(path1, path2));
+}
+
+int
+fib_path_cmp_w_route_path (fib_node_index_t path_index,
+ const fib_route_path_t *rpath)
+{
+ fib_path_t *path;
+ int res;
+
+ path = fib_path_get(path_index);
+
+ res = 1;
+
+ if (path->fp_weight != rpath->frp_weight)
+ {
+ res = (path->fp_weight - rpath->frp_weight);
+ }
+ else
+ {
+ /*
+ * both paths are of the same type.
+ * consider each type and its attributes in turn.
+ */
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ res = ip46_address_cmp(&path->attached_next_hop.fp_nh,
+ &rpath->frp_addr);
+ if (0 == res)
+ {
+ res = vnet_sw_interface_compare(
+ vnet_get_main(),
+ path->attached_next_hop.fp_interface,
+ rpath->frp_sw_if_index);
+ }
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ res = vnet_sw_interface_compare(
+ vnet_get_main(),
+ path->attached.fp_interface,
+ rpath->frp_sw_if_index);
+ break;
+ case FIB_PATH_TYPE_RECURSIVE:
+ if (FIB_PROTOCOL_MPLS == path->fp_nh_proto)
+ {
+ res = path->recursive.fp_nh.fp_local_label - rpath->frp_local_label;
+ }
+ else
+ {
+ res = ip46_address_cmp(&path->recursive.fp_nh.fp_ip,
+ &rpath->frp_addr);
+ }
+
+ if (0 == res)
+ {
+ res = (path->recursive.fp_tbl_id - rpath->frp_fib_index);
+ }
+ break;
+ case FIB_PATH_TYPE_DEAG:
+ res = (path->deag.fp_tbl_id - rpath->frp_fib_index);
+ break;
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ res = 0;
+ break;
+ }
+ }
+ return (res);
+}
+
+/*
+ * fib_path_recursive_loop_detect
+ *
+ * A forward walk of the FIB object graph to detect for a cycle/loop. This
+ * walk is initiated when an entry is linking to a new path list or from an old.
+ * The entry vector passed contains all the FIB entrys that are children of this
+ * path (it is all the entries encountered on the walk so far). If this vector
+ * contains the entry this path resolve via, then a loop is about to form.
+ * The loop must be allowed to form, since we need the dependencies in place
+ * so that we can track when the loop breaks.
+ * However, we MUST not produce a loop in the forwarding graph (else packets
+ * would loop around the switch path until the loop breaks), so we mark recursive
+ * paths as looped so that they do not contribute forwarding information.
+ * By marking the path as looped, an etry such as;
+ * X/Y
+ * via a.a.a.a (looped)
+ * via b.b.b.b (not looped)
+ * can still forward using the info provided by b.b.b.b only
+ */
+int
+fib_path_recursive_loop_detect (fib_node_index_t path_index,
+ fib_node_index_t **entry_indicies)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ /*
+ * the forced drop path is never looped, cos it is never resolved.
+ */
+ if (fib_path_is_permanent_drop(path))
+ {
+ return (0);
+ }
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_RECURSIVE:
+ {
+ fib_node_index_t *entry_index, *entries;
+ int looped = 0;
+ entries = *entry_indicies;
+
+ vec_foreach(entry_index, entries) {
+ if (*entry_index == path->fp_via_fib)
+ {
+ /*
+ * the entry that is about to link to this path-list (or
+ * one of this path-list's children) is the same entry that
+ * this recursive path resolves through. this is a cycle.
+ * abort the walk.
+ */
+ looped = 1;
+ break;
+ }
+ }
+
+ if (looped)
+ {
+ FIB_PATH_DBG(path, "recursive loop formed");
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
+
+ dpo_copy(&path->fp_dpo,
+ drop_dpo_get(fib_proto_to_dpo(path->fp_nh_proto)));
+ }
+ else
+ {
+ /*
+ * no loop here yet. keep forward walking the graph.
+ */
+ if (fib_entry_recursive_loop_detect(path->fp_via_fib, entry_indicies))
+ {
+ FIB_PATH_DBG(path, "recursive loop formed");
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
+ }
+ else
+ {
+ FIB_PATH_DBG(path, "recursive loop cleared");
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
+ }
+ }
+ break;
+ }
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ case FIB_PATH_TYPE_ATTACHED:
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_DEAG:
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ /*
+ * these path types cannot be part of a loop, since they are the leaves
+ * of the graph.
+ */
+ break;
+ }
+
+ return (fib_path_is_looped(path_index));
+}
+
+int
+fib_path_resolve (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ /*
+ * hope for the best.
+ */
+ path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
+
+ /*
+ * the forced drop path resolves via the drop adj
+ */
+ if (fib_path_is_permanent_drop(path))
+ {
+ dpo_copy(&path->fp_dpo,
+ drop_dpo_get(fib_proto_to_dpo(path->fp_nh_proto)));
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ return (fib_path_is_resolved(path_index));
+ }
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ fib_path_attached_next_hop_set(path);
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ /*
+ * path->attached.fp_interface
+ */
+ if (!vnet_sw_interface_is_admin_up(vnet_get_main(),
+ path->attached.fp_interface))
+ {
+ path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
+ }
+ if (vnet_sw_interface_is_p2p(vnet_get_main(),
+ path->attached.fp_interface))
+ {
+ /*
+ * point-2-point interfaces do not require a glean, since
+ * there is nothing to ARP. Install a rewrite/nbr adj instead
+ */
+ dpo_set(&path->fp_dpo,
+ DPO_ADJACENCY,
+ fib_proto_to_dpo(path->fp_nh_proto),
+ adj_nbr_add_or_lock(
+ path->fp_nh_proto,
+ fib_proto_to_link(path->fp_nh_proto),
+ &zero_addr,
+ path->attached.fp_interface));
+ }
+ else
+ {
+ dpo_set(&path->fp_dpo,
+ DPO_ADJACENCY_GLEAN,
+ fib_proto_to_dpo(path->fp_nh_proto),
+ adj_glean_add_or_lock(path->fp_nh_proto,
+ path->attached.fp_interface,
+ NULL));
+ }
+ /*
+ * become a child of the adjacency so we receive updates
+ * when the interface state changes
+ */
+ path->fp_sibling = adj_child_add(path->fp_dpo.dpoi_index,
+ FIB_NODE_TYPE_PATH,
+ fib_path_get_index(path));
+
+ break;
+ case FIB_PATH_TYPE_RECURSIVE:
+ {
+ /*
+ * Create a RR source entry in the table for the address
+ * that this path recurses through.
+ * This resolve action is recursive, hence we may create
+ * more paths in the process. more creates mean maybe realloc
+ * of this path.
+ */
+ fib_node_index_t fei;
+ fib_prefix_t pfx;
+
+ ASSERT(FIB_NODE_INDEX_INVALID == path->fp_via_fib);
+
+ if (FIB_PROTOCOL_MPLS == path->fp_nh_proto)
+ {
+ fib_prefix_from_mpls_label(path->recursive.fp_nh.fp_local_label, &pfx);
+ }
+ else
+ {
+ fib_prefix_from_ip46_addr(&path->recursive.fp_nh.fp_ip, &pfx);
+ }
+
+ fei = fib_table_entry_special_add(path->recursive.fp_tbl_id,
+ &pfx,
+ FIB_SOURCE_RR,
+ FIB_ENTRY_FLAG_NONE,
+ ADJ_INDEX_INVALID);
+
+ path = fib_path_get(path_index);
+ path->fp_via_fib = fei;
+
+ /*
+ * become a dependent child of the entry so the path is
+ * informed when the forwarding for the entry changes.
+ */
+ path->fp_sibling = fib_entry_child_add(path->fp_via_fib,
+ FIB_NODE_TYPE_PATH,
+ fib_path_get_index(path));
+
+ /*
+ * create and configure the IP DPO
+ */
+ fib_path_recursive_adj_update(
+ path,
+ fib_path_proto_to_chain_type(path->fp_nh_proto),
+ &path->fp_dpo);
+
+ break;
+ }
+ case FIB_PATH_TYPE_SPECIAL:
+ /*
+ * Resolve via the drop
+ */
+ dpo_copy(&path->fp_dpo,
+ drop_dpo_get(fib_proto_to_dpo(path->fp_nh_proto)));
+ break;
+ case FIB_PATH_TYPE_DEAG:
+ /*
+ * Resolve via a lookup DPO.
+ * FIXME. control plane should add routes with a table ID
+ */
+ lookup_dpo_add_or_lock_w_fib_index(path->deag.fp_tbl_id,
+ fib_proto_to_dpo(path->fp_nh_proto),
+ LOOKUP_INPUT_DST_ADDR,
+ LOOKUP_TABLE_FROM_CONFIG,
+ &path->fp_dpo);
+ break;
+ case FIB_PATH_TYPE_RECEIVE:
+ /*
+ * Resolve via a receive DPO.
+ */
+ receive_dpo_add_or_lock(fib_proto_to_dpo(path->fp_nh_proto),
+ path->receive.fp_interface,
+ &path->receive.fp_addr,
+ &path->fp_dpo);
+ break;
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ /*
+ * Resolve via the user provided DPO
+ */
+ dpo_copy(&path->fp_dpo, &path->exclusive.fp_ex_dpo);
+ break;
+ }
+
+ return (fib_path_is_resolved(path_index));
+}
+
+u32
+fib_path_get_resolving_interface (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ return (path->attached_next_hop.fp_interface);
+ case FIB_PATH_TYPE_ATTACHED:
+ return (path->attached.fp_interface);
+ case FIB_PATH_TYPE_RECEIVE:
+ return (path->receive.fp_interface);
+ case FIB_PATH_TYPE_RECURSIVE:
+ return (fib_entry_get_resolving_interface(path->fp_via_fib));
+ case FIB_PATH_TYPE_SPECIAL:
+ case FIB_PATH_TYPE_DEAG:
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ break;
+ }
+ return (~0);
+}
+
+adj_index_t
+fib_path_get_adj (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ ASSERT(dpo_is_adj(&path->fp_dpo));
+ if (dpo_is_adj(&path->fp_dpo))
+ {
+ return (path->fp_dpo.dpoi_index);
+ }
+ return (ADJ_INDEX_INVALID);
+}
+
+int
+fib_path_get_weight (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ ASSERT(path);
+
+ return (path->fp_weight);
+}
+
+/**
+ * @brief Contribute the path's adjacency to the list passed.
+ * By calling this function over all paths, recursively, a child
+ * can construct its full set of forwarding adjacencies, and hence its
+ * uRPF list.
+ */
+void
+fib_path_contribute_urpf (fib_node_index_t path_index,
+ index_t urpf)
+{
+ fib_path_t *path;
+
+ if (!fib_path_is_resolved(path_index))
+ return;
+
+ path = fib_path_get(path_index);
+
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ fib_urpf_list_append(urpf, path->attached_next_hop.fp_interface);
+ break;
+
+ case FIB_PATH_TYPE_ATTACHED:
+ fib_urpf_list_append(urpf, path->attached.fp_interface);
+ break;
+
+ case FIB_PATH_TYPE_RECURSIVE:
+ fib_entry_contribute_urpf(path->fp_via_fib, urpf);
+ break;
+
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ case FIB_PATH_TYPE_SPECIAL:
+ /*
+ * these path types may link to an adj, if that's what
+ * the clinet gave
+ */
+ if (dpo_is_adj(&path->fp_dpo))
+ {
+ ip_adjacency_t *adj;
+
+ adj = adj_get(path->fp_dpo.dpoi_index);
+
+ fib_urpf_list_append(urpf, adj->rewrite_header.sw_if_index);
+ }
+ break;
+
+ case FIB_PATH_TYPE_DEAG:
+ case FIB_PATH_TYPE_RECEIVE:
+ /*
+ * these path types don't link to an adj
+ */
+ break;
+ }
+}
+
+void
+fib_path_contribute_forwarding (fib_node_index_t path_index,
+ fib_forward_chain_type_t fct,
+ dpo_id_t *dpo)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ ASSERT(path);
+ ASSERT(FIB_FORW_CHAIN_TYPE_MPLS_EOS != fct);
+
+ FIB_PATH_DBG(path, "contribute");
+
+ /*
+ * The DPO stored in the path was created when the path was resolved.
+ * This then represents the path's 'native' protocol; IP.
+ * For all others will need to go find something else.
+ */
+ if (fib_path_proto_to_chain_type(path->fp_nh_proto) == fct)
+ {
+ dpo_copy(dpo, &path->fp_dpo);
+ }
+ else
+ {
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ switch (fct)
+ {
+ case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
+ case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
+ case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
+ case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
+ case FIB_FORW_CHAIN_TYPE_ETHERNET:
+ {
+ adj_index_t ai;
+
+ /*
+ * get a appropriate link type adj.
+ */
+ ai = fib_path_attached_next_hop_get_adj(
+ path,
+ fib_forw_chain_type_to_link_type(fct));
+ dpo_set(dpo, DPO_ADJACENCY,
+ fib_forw_chain_type_to_dpo_proto(fct), ai);
+ adj_unlock(ai);
+
+ break;
+ }
+ }
+ break;
+ case FIB_PATH_TYPE_RECURSIVE:
+ switch (fct)
+ {
+ case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
+ case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
+ case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
+ case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
+ fib_path_recursive_adj_update(path, fct, dpo);
+ break;
+ case FIB_FORW_CHAIN_TYPE_ETHERNET:
+ ASSERT(0);
+ break;
+ }
+ break;
+ case FIB_PATH_TYPE_DEAG:
+ switch (fct)
+ {
+ case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
+ lookup_dpo_add_or_lock_w_table_id(MPLS_FIB_DEFAULT_TABLE_ID,
+ DPO_PROTO_MPLS,
+ LOOKUP_INPUT_DST_ADDR,
+ LOOKUP_TABLE_FROM_CONFIG,
+ dpo);
+ break;
+ case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
+ case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
+ case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
+ dpo_copy(dpo, &path->fp_dpo);
+ break;
+ case FIB_FORW_CHAIN_TYPE_ETHERNET:
+ ASSERT(0);
+ break;
+ }
+ break;
+ case FIB_PATH_TYPE_EXCLUSIVE:
+ dpo_copy(dpo, &path->exclusive.fp_ex_dpo);
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ case FIB_PATH_TYPE_RECEIVE:
+ case FIB_PATH_TYPE_SPECIAL:
+ ASSERT(0);
+ break;
+ }
+
+ }
+}
+
+load_balance_path_t *
+fib_path_append_nh_for_multipath_hash (fib_node_index_t path_index,
+ fib_forward_chain_type_t fct,
+ load_balance_path_t *hash_key)
+{
+ load_balance_path_t *mnh;
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ ASSERT(path);
+
+ if (fib_path_is_resolved(path_index))
+ {
+ vec_add2(hash_key, mnh, 1);
+
+ mnh->path_weight = path->fp_weight;
+ mnh->path_index = path_index;
+ fib_path_contribute_forwarding(path_index, fct, &mnh->path_dpo);
+ }
+
+ return (hash_key);
+}
+
+int
+fib_path_is_recursive (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (FIB_PATH_TYPE_RECURSIVE == path->fp_type);
+}
+
+int
+fib_path_is_exclusive (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (FIB_PATH_TYPE_EXCLUSIVE == path->fp_type);
+}
+
+int
+fib_path_is_deag (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (FIB_PATH_TYPE_DEAG == path->fp_type);
+}
+
+int
+fib_path_is_resolved (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (dpo_id_is_valid(&path->fp_dpo) &&
+ (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED) &&
+ !fib_path_is_looped(path_index) &&
+ !fib_path_is_permanent_drop(path));
+}
+
+int
+fib_path_is_looped (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RECURSIVE_LOOP);
+}
+
+int
+fib_path_encode (fib_node_index_t path_list_index,
+ fib_node_index_t path_index,
+ void *ctx)
+{
+ fib_route_path_encode_t **api_rpaths = ctx;
+ fib_route_path_encode_t *api_rpath;
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+ if (!path)
+ return (0);
+ vec_add2(*api_rpaths, api_rpath, 1);
+ api_rpath->rpath.frp_weight = path->fp_weight;
+ api_rpath->rpath.frp_proto = path->fp_nh_proto;
+ api_rpath->rpath.frp_sw_if_index = ~0;
+ api_rpath->dpo = path->exclusive.fp_ex_dpo;
+ switch (path->fp_type)
+ {
+ case FIB_PATH_TYPE_RECEIVE:
+ api_rpath->rpath.frp_addr = path->receive.fp_addr;
+ api_rpath->rpath.frp_sw_if_index = path->receive.fp_interface;
+ break;
+ case FIB_PATH_TYPE_ATTACHED:
+ api_rpath->rpath.frp_sw_if_index = path->attached.fp_interface;
+ break;
+ case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
+ api_rpath->rpath.frp_sw_if_index = path->attached_next_hop.fp_interface;
+ api_rpath->rpath.frp_addr = path->attached_next_hop.fp_nh;
+ break;
+ case FIB_PATH_TYPE_SPECIAL:
+ break;
+ case FIB_PATH_TYPE_DEAG:
+ break;
+ case FIB_PATH_TYPE_RECURSIVE:
+ api_rpath->rpath.frp_addr = path->recursive.fp_nh.fp_ip;
+ break;
+ default:
+ break;
+ }
+ return (1);
+}
+
+fib_protocol_t
+fib_path_get_proto (fib_node_index_t path_index)
+{
+ fib_path_t *path;
+
+ path = fib_path_get(path_index);
+
+ return (path->fp_nh_proto);
+}
+
+void
+fib_path_module_init (void)
+{
+ fib_node_register_type (FIB_NODE_TYPE_PATH, &fib_path_vft);
+}
+
+static clib_error_t *
+show_fib_path_command (vlib_main_t * vm,
+ unformat_input_t * input,
+ vlib_cli_command_t * cmd)
+{
+ fib_node_index_t pi;
+ fib_path_t *path;
+
+ if (unformat (input, "%d", &pi))
+ {
+ /*
+ * show one in detail
+ */
+ if (!pool_is_free_index(fib_path_pool, pi))
+ {
+ path = fib_path_get(pi);
+ u8 *s = fib_path_format(pi, NULL);
+ s = format(s, "children:");
+ s = fib_node_children_format(path->fp_node.fn_children, s);
+ vlib_cli_output (vm, "%s", s);
+ vec_free(s);
+ }
+ else
+ {
+ vlib_cli_output (vm, "path %d invalid", pi);
+ }
+ }
+ else
+ {
+ vlib_cli_output (vm, "FIB Paths");
+ pool_foreach(path, fib_path_pool,
+ ({
+ vlib_cli_output (vm, "%U", format_fib_path, path);
+ }));
+ }
+
+ return (NULL);
+}
+
+VLIB_CLI_COMMAND (show_fib_path, static) = {
+ .path = "show fib paths",
+ .function = show_fib_path_command,
+ .short_help = "show fib paths",
+};