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: Anselme Sawadogo <anselmesawadogo@gmail.com>
   8  * Author: Olivier Dugeon <olivier.dugeon@orange.com>
   9  *
  10  * Copyright (C) 2016 - 2017 Orange Labs http://www.orange.com
  11  *
  12  * This file is part of FRR.
  13  *
  14  * FRR is free software; you can redistribute it and/or modify it
  15  * under the terms of the GNU General Public License as published by the
  16  * Free Software Foundation; either version 2, or (at your option) any
  17  * later version.
  18  *
  19  * FRR is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22  * General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with FRR; see the file COPYING.  If not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  27  * 02111-1307, USA.
  28  */
  29
  30 #ifndef _FRR_OSPF_EXT_PREF_H_
  31 #define _FRR_OSPF_EXT_PREF_H_
  32
  33 /*
  34  * Opaque LSA's link state ID for Extended Prefix/Link is
  35  * structured as follows.
  36  *
  37  *        24       16        8        0
  38  * +--------+--------+--------+--------+
  39  * |  7/8   |........|........|........|
  40  * +--------+--------+--------+--------+
  41  * |<-Type->|<------- Instance ------->|
  42  *
  43  *
  44  * Type:      IANA has assigned '7' for Extended Prefix Opaque LSA
  45  *                          and '8' for Extended Link Opaque LSA
  46  * Instance:  User may select arbitrary 24-bit values to identify
  47  *            different instances of Extended Prefix/Link Opaque LSA
  48  *
  49  */
  50
  51 /*
  52  *        24       16        8        0
  53  * +--------+--------+--------+--------+ ---
  54  * |   LS age        |Options |  10,11 |  A
  55  * +--------+--------+--------+--------+  |  Standard (Opaque) LSA header;
  56  * |   7/8  |        Instance          |  |
  57  * +--------+--------+--------+--------+  |  Type 10 or 11 are used for Extended
  58  * |        Advertising router         |  |  Prefix Opaque LSA
  59  * +--------+--------+--------+--------+  |
  60  * |        LS sequence number         |  |  Type 10 only is used for Extended
  61  * +--------+--------+--------+--------+  |  Link Opaque LSA
  62  * |   LS checksum   |     Length      |  V
  63  * +--------+--------+--------+--------+ ---
  64  * |      Type       |     Length      |  A
  65  * +--------+--------+--------+--------+  |  TLV part for Extended Prefix/Link
  66  * |                                   |  |  Opaque LSA;
  67  * ~              Values ...           ~  |  Values might be structured as a set
  68  * |                                   |  V  of sub-TLVs.
  69  * +--------+--------+--------+--------+ ---
  70  */
  71
  72 /* Global use constant numbers */
  73
  74 #define MAX_LEGAL_EXT_INSTANCE_NUM      (0xffff)
  75 #define LEGAL_EXT_INSTANCE_RANGE(i)     (0 <= (i) && (i) <= 0xffff)
  76
  77 /* Flags to manage Extended Link/Prefix Opaque LSA */
  78 #define EXT_LPFLG_LSA_INACTIVE          0x00
  79 #define EXT_LPFLG_LSA_ACTIVE            0x01
  80 #define EXT_LPFLG_LSA_ENGAGED           0x02
  81 #define EXT_LPFLG_LSA_LOOKUP_DONE       0x04
  82 #define EXT_LPFLG_LSA_FORCED_REFRESH    0x08
  83 #define EXT_LPFLG_FIB_ENTRY_SET         0x10
  84
  85 /*
  86  * Following section defines TLV (tag, length, value) structures,
  87  * used in Extended Prefix/Link Opaque LSA.
  88  */
  89
  90 /* Extended Prefix TLV Route Types */
  91 #define EXT_TLV_PREF_ROUTE_UNSPEC       0
  92 #define EXT_TLV_PREF_ROUTE_INTRA_AREA   1
  93 #define EXT_TLV_PREF_ROUTE_INTER_AREA   3
  94 #define EXT_TLV_PREF_ROUTE_AS_EXT       5
  95 #define EXT_TLV_PREF_ROUTE_NSSA_EXT     7
  96
  97 /* Extended Prefix and Extended Prefix Range TLVs'
  98  * Address family flag for IPv4 */
  99 #define EXT_TLV_PREF_AF_IPV4            0
 100
 101 /* Extended Prefix TLV Flags */
 102 #define EXT_TLV_PREF_AFLG               0x80
 103 #define EXT_TLV_PREF_NFLG               0x40
 104
 105 /* Extended Prefix Range TLV Flags */
 106 #define EXT_TLV_PREF_RANGE_IAFLG        0x80
 107
 108 /* ERO subtlvs Flags */
 109 #define EXT_SUBTLV_ERO_LFLG             0x80
 110
 111 /* Extended Prefix TLV see RFC 7684 section 2.1 */
 112 #define EXT_TLV_PREFIX                  1
 113 #define EXT_TLV_PREFIX_SIZE             8
 114 struct ext_tlv_prefix {
 115         struct tlv_header header;
 116         uint8_t route_type;
 117         uint8_t pref_length;
 118         uint8_t af;
 119         uint8_t flags;
 120         struct in_addr address;
 121 };
 122
 123 /* Extended Link TLV see RFC 7684 section 3.1 */
 124 #define EXT_TLV_LINK                    1
 125 #define EXT_TLV_LINK_SIZE               12
 126 struct ext_tlv_link {
 127         struct tlv_header header;
 128         uint8_t link_type;
 129         uint8_t reserved[3];
 130         struct in_addr link_id;
 131         struct in_addr link_data;
 132 };
 133
 134 /* Remote Interface Address Sub-TLV, Cisco experimental use Sub-TLV */
 135 #define EXT_SUBTLV_RMT_ITF_ADDR         32768
 136 #define EXT_SUBTLV_RMT_ITF_ADDR_SIZE    4
 137 struct ext_subtlv_rmt_itf_addr {
 138         struct tlv_header header;
 139         struct in_addr value;
 140 };
 141
 142 /* Internal structure to manage Extended Link/Prefix Opaque LSA */
 143 struct ospf_ext_lp {
 144         bool enabled;
 145
 146         /* Flags to manage this Extended Prefix/Link Opaque LSA */
 147         uint32_t flags;
 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         uint8_t scope;
 152
 153         /* area pointer if flooding is Type 10 Null if flooding is AS scope */
 154         struct ospf_area *area;
 155         struct in_addr area_id;
 156
 157         /* List of interface with Segment Routing enable */
 158         struct list *iflist;
 159 };
 160
 161 /* Structure to aggregate interfaces information for Extended Prefix/Link */
 162 struct ext_itf {
 163         /* 24-bit Opaque-ID field value according to RFC 7684 specification */
 164         uint32_t instance;
 165         uint8_t type; /* Extended Prefix (7) or Link (8) */
 166
 167         /* Reference pointer to a Zebra-interface. */
 168         struct interface *ifp;
 169
 170         /* Area info in which this SR link belongs to. */
 171         struct ospf_area *area;
 172
 173         /* Flags to manage this link parameters. */
 174         uint32_t flags;
 175
 176         /* SID type: Node, Adjacency or LAN Adjacency */
 177         enum sid_type stype;
 178
 179         /* extended link/prefix TLV information */
 180         struct ext_tlv_prefix prefix;
 181         struct ext_subtlv_prefix_sid node_sid;
 182         struct ext_tlv_link link;
 183         struct ext_subtlv_adj_sid adj_sid[2];
 184         struct ext_subtlv_lan_adj_sid lan_sid[2];
 185
 186         /* cisco experimental subtlv */
 187         struct ext_subtlv_rmt_itf_addr rmt_itf_addr;
 188 };
 189
 190 /* Prototypes. */
 191 extern int ospf_ext_init(void);
 192 extern void ospf_ext_term(void);
 193 extern void ospf_ext_update_sr(bool);
 194 extern int ospf_ext_schedule_prefix_index(struct interface *, uint32_t,
 195                                           struct prefix_ipv4 *);
 196 #endif /* _FRR_OSPF_EXT_PREF_H_ */