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Diffstat (limited to 'src/vnet/adj/adj.h')
| -rw-r--r-- | src/vnet/adj/adj.h | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/src/vnet/adj/adj.h b/src/vnet/adj/adj.h new file mode 100644 index 00000000..ed5eb1f1 --- /dev/null +++ b/src/vnet/adj/adj.h @@ -0,0 +1,379 @@ +/* + * 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. + */ +/** + * An adjacency is a representation of an attached L3 peer. + * + * Adjacency Sub-types: + * - neighbour: a representation of an attached L3 peer. + * Key:{addr,interface,link/ether-type} + * SHARED + * - glean: used to drive ARP/ND for packets destined to a local sub-net. + * 'glean' mean use the packet's destination address as the target + * address in the ARP packet. + * UNSHARED. Only one per-interface. + * - midchain: a nighbour adj on a virtual/tunnel interface. + * + * The API to create and update the adjacency is very sub-type specific. This + * is intentional as it encourages the user to carefully consider which adjacency + * sub-type they are really using, and hence assign it data in the appropriate + * sub-type space in the union of sub-types. This prevents the adj becoming a + * disorganised dumping group for 'my features needs a u16 somewhere' data. It + * is important to enforce this approach as space in the adjacency is a premium, + * as we need it to fit in 1 cache line. + * + * the API is also based around an index to an ajdacency not a raw pointer. This + * is so the user doesn't suffer the same limp inducing firearm injuries that + * the author suffered as the adjacenices can realloc. + */ + +#ifndef __ADJ_H__ +#define __ADJ_H__ + +#include <vnet/adj/adj_types.h> +#include <vnet/adj/adj_nbr.h> +#include <vnet/adj/adj_glean.h> +#include <vnet/adj/rewrite.h> + +/** @brief Common (IP4/IP6) next index stored in adjacency. */ +typedef enum +{ + /** Adjacency to drop this packet. */ + IP_LOOKUP_NEXT_DROP, + /** Adjacency to punt this packet. */ + IP_LOOKUP_NEXT_PUNT, + + /** This packet is for one of our own IP addresses. */ + IP_LOOKUP_NEXT_LOCAL, + + /** This packet matches an "incomplete adjacency" and packets + need to be passed to ARP to find rewrite string for + this destination. */ + IP_LOOKUP_NEXT_ARP, + + /** This packet matches an "interface route" and packets + need to be passed to ARP to find rewrite string for + this destination. */ + IP_LOOKUP_NEXT_GLEAN, + + /** This packet is to be rewritten and forwarded to the next + processing node. This is typically the output interface but + might be another node for further output processing. */ + IP_LOOKUP_NEXT_REWRITE, + + /** This packets follow a mid-chain adjacency */ + IP_LOOKUP_NEXT_MIDCHAIN, + + /** This packets needs to go to ICMP error */ + IP_LOOKUP_NEXT_ICMP_ERROR, + + /** Multicast Adjacency. */ + IP_LOOKUP_NEXT_MCAST, + + /** Multicast Midchain Adjacency. An Adjacency for sending macst packets + * on a tunnel/virtual interface */ + IP_LOOKUP_NEXT_MCAST_MIDCHAIN, + + IP_LOOKUP_N_NEXT, +} __attribute__ ((packed)) ip_lookup_next_t; + +typedef enum +{ + IP4_LOOKUP_N_NEXT = IP_LOOKUP_N_NEXT, +} ip4_lookup_next_t; + +typedef enum +{ + /* Hop-by-hop header handling */ + IP6_LOOKUP_NEXT_HOP_BY_HOP = IP_LOOKUP_N_NEXT, + IP6_LOOKUP_NEXT_ADD_HOP_BY_HOP, + IP6_LOOKUP_NEXT_POP_HOP_BY_HOP, + IP6_LOOKUP_N_NEXT, +} ip6_lookup_next_t; + +#define IP4_LOOKUP_NEXT_NODES { \ + [IP_LOOKUP_NEXT_DROP] = "ip4-drop", \ + [IP_LOOKUP_NEXT_PUNT] = "ip4-punt", \ + [IP_LOOKUP_NEXT_LOCAL] = "ip4-local", \ + [IP_LOOKUP_NEXT_ARP] = "ip4-arp", \ + [IP_LOOKUP_NEXT_GLEAN] = "ip4-glean", \ + [IP_LOOKUP_NEXT_REWRITE] = "ip4-rewrite", \ + [IP_LOOKUP_NEXT_MCAST] = "ip4-rewrite-mcast", \ + [IP_LOOKUP_NEXT_MIDCHAIN] = "ip4-midchain", \ + [IP_LOOKUP_NEXT_MCAST_MIDCHAIN] = "ip4-mcast-midchain", \ + [IP_LOOKUP_NEXT_ICMP_ERROR] = "ip4-icmp-error", \ +} + +#define IP6_LOOKUP_NEXT_NODES { \ + [IP_LOOKUP_NEXT_DROP] = "ip6-drop", \ + [IP_LOOKUP_NEXT_PUNT] = "ip6-punt", \ + [IP_LOOKUP_NEXT_LOCAL] = "ip6-local", \ + [IP_LOOKUP_NEXT_ARP] = "ip6-discover-neighbor", \ + [IP_LOOKUP_NEXT_GLEAN] = "ip6-glean", \ + [IP_LOOKUP_NEXT_REWRITE] = "ip6-rewrite", \ + [IP_LOOKUP_NEXT_MCAST] = "ip6-rewrite-mcast", \ + [IP_LOOKUP_NEXT_MIDCHAIN] = "ip6-midchain", \ + [IP_LOOKUP_NEXT_MCAST_MIDCHAIN] = "ip6-mcast-midchain", \ + [IP_LOOKUP_NEXT_ICMP_ERROR] = "ip6-icmp-error", \ + [IP6_LOOKUP_NEXT_HOP_BY_HOP] = "ip6-hop-by-hop", \ + [IP6_LOOKUP_NEXT_ADD_HOP_BY_HOP] = "ip6-add-hop-by-hop", \ + [IP6_LOOKUP_NEXT_POP_HOP_BY_HOP] = "ip6-pop-hop-by-hop", \ +} + +/** + * Forward delcartion + */ +struct ip_adjacency_t_; + +/** + * @brief A function type for post-rewrite fixups on midchain adjacency + */ +typedef void (*adj_midchain_fixup_t) (vlib_main_t * vm, + struct ip_adjacency_t_ * adj, + vlib_buffer_t * b0); + +/** + * @brief Flags on an IP adjacency + */ +typedef enum ip_adjacency_flags_t_ +{ + ADJ_FLAG_NONE = 0, + + /** + * Currently a sync walk is active. Used to prevent re-entrant walking + */ + ADJ_FLAG_SYNC_WALK_ACTIVE = (1 << 0), + + /** + * Packets TX through the midchain do not increment the interface + * counters. This should be used when the adj is associated with an L2 + * interface and that L2 interface is in a bridege domain. In that case + * the packet will have traversed the interface's TX node, and hence have + * been counted, before it traverses ths midchain + */ + ADJ_FLAG_MIDCHAIN_NO_COUNT = (1 << 1), +} __attribute__ ((packed)) adj_flags_t; + +/** + * @brief IP unicast adjacency. + * @note cache aligned. + * + * An adjacency is a represenation of a peer on a particular link. + */ +typedef struct ip_adjacency_t_ +{ + CLIB_CACHE_LINE_ALIGN_MARK (cacheline0); + + /** + * Linkage into the FIB node grpah. First member since this type + * has 8 byte alignment requirements. + */ + fib_node_t ia_node; + + /** + * Next hop after ip4-lookup. + * This is not accessed in the rewrite nodes. + * 1-bytes + */ + ip_lookup_next_t lookup_next_index; + + /** + * link/ether-type + * 1 bytes + */ + vnet_link_t ia_link; + + /** + * The protocol of the neighbor/peer. i.e. the protocol with + * which to interpret the 'next-hop' attirbutes of the sub-types. + * 1-btyes + */ + fib_protocol_t ia_nh_proto; + + /** + * Flags on the adjacency + * 1-bytes + */ + adj_flags_t ia_flags; + + union + { + /** + * IP_LOOKUP_NEXT_ARP/IP_LOOKUP_NEXT_REWRITE + * + * neighbour adjacency sub-type; + */ + struct + { + ip46_address_t next_hop; + } nbr; + /** + * IP_LOOKUP_NEXT_MIDCHAIN + * + * A nbr adj that is also recursive. Think tunnels. + * A nbr adj can transition to be of type MDICHAIN + * so be sure to leave the two structs with the next_hop + * fields aligned. + */ + struct + { + /** + * The recursive next-hop. + * This field MUST be at the same memory location as + * sub_type.nbr.next_hop + */ + ip46_address_t next_hop; + /** + * The next DPO to use + */ + dpo_id_t next_dpo; + /** + * A function to perform the post-rewrite fixup + */ + adj_midchain_fixup_t fixup_func; + } midchain; + /** + * IP_LOOKUP_NEXT_GLEAN + * + * Glean the address to ARP for from the packet's destination. + * Technically these aren't adjacencies, i.e. they are not a + * representation of a peer. One day we might untangle this coupling + * and use a new Glean DPO. + */ + struct + { + ip46_address_t receive_addr; + } glean; + } sub_type; + + CLIB_CACHE_LINE_ALIGN_MARK (cacheline1); + + /* Rewrite in second/third cache lines */ + vnet_declare_rewrite (VLIB_BUFFER_PRE_DATA_SIZE); + + /** + * more control plane members that do not fit on the first cacheline + */ + /** + * A sorted vector of delegates + */ + struct adj_delegate_t_ *ia_delegates; + +} ip_adjacency_t; + +STATIC_ASSERT ((STRUCT_OFFSET_OF (ip_adjacency_t, cacheline0) == 0), + "IP adjacency cachline 0 is not offset"); +STATIC_ASSERT ((STRUCT_OFFSET_OF (ip_adjacency_t, cacheline1) == + CLIB_CACHE_LINE_BYTES), + "IP adjacency cachline 1 is more than one cachline size offset"); + +/** + * @brief + * Take a reference counting lock on the adjacency + */ +extern void adj_lock(adj_index_t adj_index); +/** + * @brief + * Release a reference counting lock on the adjacency + */ +extern void adj_unlock(adj_index_t adj_index); + +/** + * @brief + * Add a child dependent to an adjacency. The child will + * thus be informed via its registerd back-walk function + * when the adjacency state changes. + */ +extern u32 adj_child_add(adj_index_t adj_index, + fib_node_type_t type, + fib_node_index_t child_index); +/** + * @brief + * Remove a child dependent + */ +extern void adj_child_remove(adj_index_t adj_index, + u32 sibling_index); + +/** + * @brief Walk the Adjacencies on a given interface + */ +extern void adj_walk (u32 sw_if_index, + adj_walk_cb_t cb, + void *ctx); + +/** + * @brief Return the link type of the adjacency + */ +extern vnet_link_t adj_get_link_type (adj_index_t ai); + +/** + * @brief Return the sw interface index of the adjacency. + */ +extern u32 adj_get_sw_if_index (adj_index_t ai); + +/** + * @brief Return true if the adjacency is 'UP', i.e. can be used for forwarding. + * 0 is down, !0 is up. + */ +extern int adj_is_up (adj_index_t ai); + +/** + * @brief Return the link type of the adjacency + */ +extern const u8* adj_get_rewrite (adj_index_t ai); + +/** + * @brief Notify the adjacency subsystem that the features settings for + * an interface have changed + */ +extern void adj_feature_update (u32 sw_if_index, u8 arc_index, u8 is_enable); + +/** + * @brief + * The global adjacnecy pool. Exposed for fast/inline data-plane access + */ +extern ip_adjacency_t *adj_pool; + +/** + * @brief + * Adjacency packet counters + */ +extern vlib_combined_counter_main_t adjacency_counters; + +/** + * @brief Global Config for enabling per-adjacency counters + * This is configurable because it comes with a non-negligible + * performance cost. */ +extern int adj_per_adj_counters; + +/** + * @brief + * Get a pointer to an adjacency object from its index + */ +static inline ip_adjacency_t * +adj_get (adj_index_t adj_index) +{ + return (vec_elt_at_index(adj_pool, adj_index)); +} + +/** + * @brief Get the global configuration option for enabling per-adj counters + */ +static inline int +adj_are_counters_enabled (void) +{ + return (adj_per_adj_counters); +} + +#endif |