ospfd/ospf_ext.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * This is an implementation of RFC7684 OSPFv2 Prefix/Link Attribute
   4  * Advertisement
   5  *
   6  * Module name: Extended Prefix/Link Opaque LSA header definition
   7  *
   8  * Author: Olivier Dugeon <olivier.dugeon@orange.com>
   9  * Author: Anselme Sawadogo <anselmesawadogo@gmail.com>
  10  *
  11  * Copyright (C) 2016 - 2018 Orange Labs http://www.orange.com
  12  */
  13
  14 #ifndef _FRR_OSPF_EXT_PREF_H_
  15 #define _FRR_OSPF_EXT_PREF_H_
  16
  17 /*
  18  * Opaque LSA's link state ID for Extended Prefix/Link is
  19  * structured as follows.
  20  *
  21  *        24       16        8        0
  22  * +--------+--------+--------+--------+
  23  * |  7/8   |........|........|........|
  24  * +--------+--------+--------+--------+
  25  * |<-Type->|<------- Instance ------->|
  26  *
  27  *
  28  * Type:      IANA has assigned '7' for Extended Prefix Opaque LSA
  29  *            and '8' for Extended Link Opaque LSA
  30  * Instance:  User may select arbitrary 24-bit values to identify
  31  *            different instances of Extended Prefix/Link Opaque LSA
  32  *
  33  */
  34
  35 /*
  36  *        24       16        8        0
  37  * +--------+--------+--------+--------+ ---
  38  * |   LS age        |Options |  10,11 |  A
  39  * +--------+--------+--------+--------+  |  Standard (Opaque) LSA header;
  40  * |   7/8  |        Instance          |  |
  41  * +--------+--------+--------+--------+  |  Type 10 or 11 are used for Extended
  42  * |        Advertising router         |  |  Prefix Opaque LSA
  43  * +--------+--------+--------+--------+  |
  44  * |        LS sequence number         |  |  Type 10 only is used for Extended
  45  * +--------+--------+--------+--------+  |  Link Opaque LSA
  46  * |   LS checksum   |     Length      |  V
  47  * +--------+--------+--------+--------+ ---
  48  * |      Type       |     Length      |  A
  49  * +--------+--------+--------+--------+  |  TLV part for Extended Prefix/Link
  50  * |                                   |  |  Opaque LSA;
  51  * ~              Values ...           ~  |  Values might be structured as a set
  52  * |                                   |  V  of sub-TLVs.
  53  * +--------+--------+--------+--------+ ---
  54  */
  55
  56 /* Global use constant numbers */
  57
  58 #define MAX_LEGAL_EXT_INSTANCE_NUM      (0xffff)
  59 #define LEGAL_EXT_INSTANCE_RANGE(i)     (0 <= (i) && (i) <= 0xffff)
  60
  61 /* Flags to manage Extended Link/Prefix Opaque LSA */
  62 #define EXT_LPFLG_LSA_INACTIVE          0x00
  63 #define EXT_LPFLG_LSA_ACTIVE            0x01
  64 #define EXT_LPFLG_LSA_ENGAGED           0x02
  65 #define EXT_LPFLG_LSA_LOOKUP_DONE       0x04
  66 #define EXT_LPFLG_LSA_FORCED_REFRESH    0x08
  67 #define EXT_LPFLG_FIB_ENTRY_SET         0x10
  68
  69 /*
  70  * Following section defines TLV (tag, length, value) structures,
  71  * used in Extended Prefix/Link Opaque LSA.
  72  */
  73
  74 /* Extended Prefix TLV Route Types */
  75 #define EXT_TLV_PREF_ROUTE_UNSPEC       0
  76 #define EXT_TLV_PREF_ROUTE_INTRA_AREA   1
  77 #define EXT_TLV_PREF_ROUTE_INTER_AREA   3
  78 #define EXT_TLV_PREF_ROUTE_AS_EXT       5
  79 #define EXT_TLV_PREF_ROUTE_NSSA_EXT     7
  80
  81 /*
  82  * Extended Prefix and Extended Prefix Range TLVs'
  83  * Address family flag for IPv4
  84  */
  85 #define EXT_TLV_PREF_AF_IPV4            0
  86
  87 /* Extended Prefix TLV Flags */
  88 #define EXT_TLV_PREF_AFLG               0x80
  89 #define EXT_TLV_PREF_NFLG               0x40
  90
  91 /* Extended Prefix Range TLV Flags */
  92 #define EXT_TLV_PREF_RANGE_IAFLG        0x80
  93
  94 /* ERO subtlvs Flags */
  95 #define EXT_SUBTLV_ERO_LFLG             0x80
  96
  97 /* Extended Prefix TLV see RFC 7684 section 2.1 */
  98 #define EXT_TLV_PREFIX                  1
  99 #define EXT_TLV_PREFIX_SIZE             8
 100 struct ext_tlv_prefix {
 101         struct tlv_header header;
 102         uint8_t route_type;
 103         uint8_t pref_length;
 104         uint8_t af;
 105         uint8_t flags;
 106         struct in_addr address;
 107 };
 108
 109 /* Extended Link TLV see RFC 7684 section 3.1 */
 110 #define EXT_TLV_LINK                    1
 111 #define EXT_TLV_LINK_SIZE               12
 112 struct ext_tlv_link {
 113         struct tlv_header header;
 114         uint8_t link_type;
 115         uint8_t reserved[3];
 116         struct in_addr link_id;
 117         struct in_addr link_data;
 118 };
 119
 120 /* Remote Interface Address Sub-TLV, Cisco experimental use Sub-TLV */
 121 #define EXT_SUBTLV_RMT_ITF_ADDR         32768
 122 #define EXT_SUBTLV_RMT_ITF_ADDR_SIZE    4
 123 struct ext_subtlv_rmt_itf_addr {
 124         struct tlv_header header;
 125         struct in_addr value;
 126 };
 127
 128 /* Internal structure to manage Extended Link/Prefix Opaque LSA */
 129 struct ospf_ext_lp {
 130         bool enabled;
 131
 132         /* Flags to manage this Extended Prefix/Link Opaque LSA */
 133         uint32_t flags;
 134
 135         /*
 136          * Scope is area Opaque Type 10 or AS Opaque LSA Type 11 for
 137          * Extended Prefix and area Opaque Type 10 for Extended Link
 138          */
 139         uint8_t scope;
 140
 141         /* List of interface with Segment Routing enable */
 142         struct list *iflist;
 143 };
 144
 145 /* Structure to aggregate interfaces information for Extended Prefix/Link */
 146 struct ext_itf {
 147         /* 24-bit Opaque-ID field value according to RFC 7684 specification */
 148         uint32_t instance;
 149         uint8_t type; /* Extended Prefix (7) or Link (8) */
 150
 151         /* Reference pointer to a Zebra-interface. */
 152         struct interface *ifp;
 153
 154         /* Area info in which this SR link belongs to. */
 155         struct ospf_area *area;
 156
 157         /* Flags to manage this link parameters. */
 158         uint32_t flags;
 159
 160         /* SID type: Node, Adjacency or LAN Adjacency */
 161         enum sid_type stype;
 162
 163         /* extended link/prefix TLV information */
 164         struct ext_tlv_prefix prefix;
 165         struct ext_subtlv_prefix_sid node_sid;
 166         struct ext_tlv_link link;
 167         struct ext_subtlv_adj_sid adj_sid[2];
 168         struct ext_subtlv_lan_adj_sid lan_sid[2];
 169
 170         /* cisco experimental subtlv */
 171         struct ext_subtlv_rmt_itf_addr rmt_itf_addr;
 172 };
 173
 174 /* Prototypes. */
 175 extern int ospf_ext_init(void);
 176 extern void ospf_ext_term(void);
 177 extern void ospf_ext_finish(void);
 178 extern void ospf_ext_update_sr(bool enable);
 179 extern void ospf_ext_link_srlb_update(void);
 180 extern uint32_t ospf_ext_schedule_prefix_index(struct interface *ifp,
 181                                                uint32_t index,
 182                                                struct prefix_ipv4 *p,
 183                                                uint8_t flags);
 184 #endif /* _FRR_OSPF_EXT_PREF_H_ */