ospfd/ospf_ext.h

   1 /*
   2  * This is an implementation of RFC7684 OSPFv2 Prefix/Link Attribute
   3  * Advertisement
   4  *
   5  * Module name: Extended Prefix/Link Opaque LSA header definition
   6  *
   7  * Author: Olivier Dugeon <olivier.dugeon@orange.com>
   8  * Author: Anselme Sawadogo <anselmesawadogo@gmail.com>
   9  *
  10  * Copyright (C) 2016 - 2018 Orange Labs http://www.orange.com
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 2 of the License, or (at your option)
  15  * any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  20  * more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; see the file COPYING; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  25  */
  26
  27 #ifndef _FRR_OSPF_EXT_PREF_H_
  28 #define _FRR_OSPF_EXT_PREF_H_
  29
  30 /*
  31  * Opaque LSA's link state ID for Extended Prefix/Link is
  32  * structured as follows.
  33  *
  34  *        24       16        8        0
  35  * +--------+--------+--------+--------+
  36  * |  7/8   |........|........|........|
  37  * +--------+--------+--------+--------+
  38  * |<-Type->|<------- Instance ------->|
  39  *
  40  *
  41  * Type:      IANA has assigned '7' for Extended Prefix Opaque LSA
  42  *            and '8' for Extended Link Opaque LSA
  43  * Instance:  User may select arbitrary 24-bit values to identify
  44  *            different instances of Extended Prefix/Link Opaque LSA
  45  *
  46  */
  47
  48 /*
  49  *        24       16        8        0
  50  * +--------+--------+--------+--------+ ---
  51  * |   LS age        |Options |  10,11 |  A
  52  * +--------+--------+--------+--------+  |  Standard (Opaque) LSA header;
  53  * |   7/8  |        Instance          |  |
  54  * +--------+--------+--------+--------+  |  Type 10 or 11 are used for Extended
  55  * |        Advertising router         |  |  Prefix Opaque LSA
  56  * +--------+--------+--------+--------+  |
  57  * |        LS sequence number         |  |  Type 10 only is used for Extended
  58  * +--------+--------+--------+--------+  |  Link Opaque LSA
  59  * |   LS checksum   |     Length      |  V
  60  * +--------+--------+--------+--------+ ---
  61  * |      Type       |     Length      |  A
  62  * +--------+--------+--------+--------+  |  TLV part for Extended Prefix/Link
  63  * |                                   |  |  Opaque LSA;
  64  * ~              Values ...           ~  |  Values might be structured as a set
  65  * |                                   |  V  of sub-TLVs.
  66  * +--------+--------+--------+--------+ ---
  67  */
  68
  69 /* Global use constant numbers */
  70
  71 #define MAX_LEGAL_EXT_INSTANCE_NUM      (0xffff)
  72 #define LEGAL_EXT_INSTANCE_RANGE(i)     (0 <= (i) && (i) <= 0xffff)
  73
  74 /* Flags to manage Extended Link/Prefix Opaque LSA */
  75 #define EXT_LPFLG_LSA_INACTIVE          0x00
  76 #define EXT_LPFLG_LSA_ACTIVE            0x01
  77 #define EXT_LPFLG_LSA_ENGAGED           0x02
  78 #define EXT_LPFLG_LSA_LOOKUP_DONE       0x04
  79 #define EXT_LPFLG_LSA_FORCED_REFRESH    0x08
  80 #define EXT_LPFLG_FIB_ENTRY_SET         0x10
  81
  82 /*
  83  * Following section defines TLV (tag, length, value) structures,
  84  * used in Extended Prefix/Link Opaque LSA.
  85  */
  86
  87 /* Extended Prefix TLV Route Types */
  88 #define EXT_TLV_PREF_ROUTE_UNSPEC       0
  89 #define EXT_TLV_PREF_ROUTE_INTRA_AREA   1
  90 #define EXT_TLV_PREF_ROUTE_INTER_AREA   3
  91 #define EXT_TLV_PREF_ROUTE_AS_EXT       5
  92 #define EXT_TLV_PREF_ROUTE_NSSA_EXT     7
  93
  94 /*
  95  * Extended Prefix and Extended Prefix Range TLVs'
  96  * Address family flag for IPv4
  97  */
  98 #define EXT_TLV_PREF_AF_IPV4            0
  99
 100 /* Extended Prefix TLV Flags */
 101 #define EXT_TLV_PREF_AFLG               0x80
 102 #define EXT_TLV_PREF_NFLG               0x40
 103
 104 /* Extended Prefix Range TLV Flags */
 105 #define EXT_TLV_PREF_RANGE_IAFLG        0x80
 106
 107 /* ERO subtlvs Flags */
 108 #define EXT_SUBTLV_ERO_LFLG             0x80
 109
 110 /* Extended Prefix TLV see RFC 7684 section 2.1 */
 111 #define EXT_TLV_PREFIX                  1
 112 #define EXT_TLV_PREFIX_SIZE             8
 113 struct ext_tlv_prefix {
 114         struct tlv_header header;
 115         uint8_t route_type;
 116         uint8_t pref_length;
 117         uint8_t af;
 118         uint8_t flags;
 119         struct in_addr address;
 120 };
 121
 122 /* Extended Link TLV see RFC 7684 section 3.1 */
 123 #define EXT_TLV_LINK                    1
 124 #define EXT_TLV_LINK_SIZE               12
 125 struct ext_tlv_link {
 126         struct tlv_header header;
 127         uint8_t link_type;
 128         uint8_t reserved[3];
 129         struct in_addr link_id;
 130         struct in_addr link_data;
 131 };
 132
 133 /* Remote Interface Address Sub-TLV, Cisco experimental use Sub-TLV */
 134 #define EXT_SUBTLV_RMT_ITF_ADDR         32768
 135 #define EXT_SUBTLV_RMT_ITF_ADDR_SIZE    4
 136 struct ext_subtlv_rmt_itf_addr {
 137         struct tlv_header header;
 138         struct in_addr value;
 139 };
 140
 141 /* Internal structure to manage Extended Link/Prefix Opaque LSA */
 142 struct ospf_ext_lp {
 143         bool enabled;
 144
 145         /* Flags to manage this Extended Prefix/Link Opaque LSA */
 146         uint32_t flags;
 147
 148         /*
 149          * Scope is area Opaque Type 10 or AS Opaque LSA Type 11 for
 150          * Extended Prefix and area Opaque Type 10 for Extended Link
 151          */
 152         uint8_t scope;
 153
 154         /* area pointer if flooding is Type 10 Null if flooding is AS scope */
 155         struct ospf_area *area;
 156         struct in_addr area_id;
 157
 158         /* List of interface with Segment Routing enable */
 159         struct list *iflist;
 160 };
 161
 162 /* Structure to aggregate interfaces information for Extended Prefix/Link */
 163 struct ext_itf {
 164         /* 24-bit Opaque-ID field value according to RFC 7684 specification */
 165         uint32_t instance;
 166         uint8_t type; /* Extended Prefix (7) or Link (8) */
 167
 168         /* Reference pointer to a Zebra-interface. */
 169         struct interface *ifp;
 170
 171         /* Area info in which this SR link belongs to. */
 172         struct ospf_area *area;
 173
 174         /* Flags to manage this link parameters. */
 175         uint32_t flags;
 176
 177         /* SID type: Node, Adjacency or LAN Adjacency */
 178         enum sid_type stype;
 179
 180         /* extended link/prefix TLV information */
 181         struct ext_tlv_prefix prefix;
 182         struct ext_subtlv_prefix_sid node_sid;
 183         struct ext_tlv_link link;
 184         struct ext_subtlv_adj_sid adj_sid[2];
 185         struct ext_subtlv_lan_adj_sid lan_sid[2];
 186
 187         /* cisco experimental subtlv */
 188         struct ext_subtlv_rmt_itf_addr rmt_itf_addr;
 189 };
 190
 191 /* Prototypes. */
 192 extern int ospf_ext_init(void);
 193 extern void ospf_ext_term(void);
 194 extern void ospf_ext_finish(void);
 195 extern void ospf_ext_update_sr(bool enable);
 196 extern uint32_t ospf_ext_schedule_prefix_index(struct interface *ifp,
 197                                                uint32_t index,
 198                                                struct prefix_ipv4 *p,
 199                                                uint8_t flags);
 200 #endif /* _FRR_OSPF_EXT_PREF_H_ */