1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2010-2014 Intel Corporation 3 */ 4 5 #ifndef __INCLUDE_RTE_TABLE_LPM_IPV6_H__ 6 #define __INCLUDE_RTE_TABLE_LPM_IPV6_H__ 7 8 /** 9 * @file 10 * RTE Table LPM for IPv6 11 * 12 * This table uses the Longest Prefix Match (LPM) algorithm to uniquely 13 * associate data to lookup keys. 14 * 15 * Use-case: IP routing table. Routes that are added to the table associate a 16 * next hop to an IP prefix. The IP prefix is specified as IP address and depth 17 * and cover for a multitude of lookup keys (i.e. destination IP addresses) 18 * that all share the same data (i.e. next hop). The next hop information 19 * typically contains the output interface ID, the IP address of the next hop 20 * station (which is part of the same IP network the output interface is 21 * connected to) and other flags and counters. 22 * 23 * The LPM primitive only allows associating an 8-bit number (next hop ID) to 24 * an IP prefix, while a routing table can potentially contain thousands of 25 * routes or even more. This means that the same next hop ID (and next hop 26 * information) has to be shared by multiple routes, which makes sense, as 27 * multiple remote networks could be reached through the same next hop. 28 * Therefore, when a route is added or updated, the LPM table has to check 29 * whether the same next hop is already in use before using a new next hop ID 30 * for this route. 31 * 32 * The comparison between different next hops is done for the first 33 * “entry_unique_size” bytes of the next hop information (configurable 34 * parameter), which have to uniquely identify the next hop, therefore the user 35 * has to carefully manage the format of the LPM table entry (i.e. the next 36 * hop information) so that any next hop data that changes value during 37 * run-time (e.g. counters) is placed outside of this area. 38 */ 39 40 #include <stdint.h> 41 42 #include <rte_common.h> 43 #include <rte_ip6.h> 44 45 #include "rte_table.h" 46 47 #ifdef __cplusplus 48 extern "C" { 49 #endif 50 51 #define RTE_LPM_IPV6_ADDR_SIZE (RTE_DEPRECATED(RTE_LPM_IPV6_ADDR_SIZE) RTE_IPV6_ADDR_SIZE) 52 53 /** LPM table parameters */ 54 struct rte_table_lpm_ipv6_params { 55 /** Table name */ 56 const char *name; 57 58 /** Maximum number of LPM rules (i.e. IP routes) */ 59 uint32_t n_rules; 60 61 uint32_t number_tbl8s; 62 63 /** Number of bytes at the start of the table entry that uniquely 64 identify the entry. Cannot be bigger than table entry size. */ 65 uint32_t entry_unique_size; 66 67 /** Byte offset within input packet meta-data where lookup key (i.e. 68 the destination IP address) is located. */ 69 uint32_t offset; 70 }; 71 72 /** LPM table rule (i.e. route), specified as IP prefix. While the key used by 73 the lookup operation is the destination IP address (read from the input packet 74 meta-data), the entry add and entry delete operations work with LPM rules, with 75 each rule covering for a multitude of lookup keys (destination IP addresses) 76 that share the same data (next hop). */ 77 struct rte_table_lpm_ipv6_key { 78 /** IP address */ 79 struct rte_ipv6_addr ip; 80 81 /** IP address depth. The most significant "depth" bits of the IP 82 address specify the network part of the IP address, while the rest of 83 the bits specify the host part of the address and are ignored for the 84 purpose of route specification. */ 85 uint8_t depth; 86 }; 87 88 /** LPM table operations */ 89 extern struct rte_table_ops rte_table_lpm_ipv6_ops; 90 91 #ifdef __cplusplus 92 } 93 #endif 94 95 #endif 96