isisd/isis_pdu.h

   1 /*
   2  * IS-IS Rout(e)ing protocol - isis_pdu.h
   3  *                             PDU processing
   4  *
   5  * Copyright (C) 2001,2002   Sampo Saaristo
   6  *                           Tampere University of Technology
   7  *                           Institute of Communications Engineering
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public Licenseas published by the Free
  11  * Software Foundation; either version 2 of the License, or (at your option)
  12  * any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  22  */
  23
  24 #ifndef _ZEBRA_ISIS_PDU_H
  25 #define _ZEBRA_ISIS_PDU_H
  26
  27 #ifdef __SUNPRO_C
  28 #pragma pack(1)
  29 #endif
  30
  31 /*
  32  *                    ISO 9542 - 7.5,7.6
  33  *
  34  *                       ES to IS Fixed Header
  35  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  36  *  |         Intradomain Routeing Protocol Discriminator           |
  37  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  38  *  |                       Length Indicator                        |
  39  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  40  *  |                  Version/Protocol ID extension                |
  41  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  42  *  |                         Reserved = 0                          |
  43  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  44  *  |   0   |   0   |   0   |              PDU Type                 |
  45  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  46  *  |                         Holding Time                          | 2
  47  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  48  *  |                          Checksum                             | 2
  49  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  50  */
  51
  52 struct esis_fixed_hdr
  53 {
  54   u_char idrp;
  55   u_char length;
  56   u_char version;
  57   u_char id_len;
  58   u_char pdu_type;
  59   u_int16_t holdtime;
  60   u_int16_t checksum;
  61 } __attribute__ ((packed));
  62
  63 #define ESIS_FIXED_HDR_LEN   9
  64
  65 #define ESH_PDU              2
  66 #define ISH_PDU              4
  67 #define RD_PDU               5
  68
  69 /*
  70  *                       IS to IS Fixed Header
  71  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  72  *  |         Intradomain Routeing Protocol Discriminator           |
  73  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  74  *  |                       Length Indicator                        |
  75  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  76  *  |                  Version/Protocol ID extension                |
  77  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  78  *  |   R   |   R   |   R   |              PDU Type                 |
  79  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  80  *  |                            Version                            |
  81  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  82  *  |                            Reserved                           |
  83  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  84  *  |                       Maximum Area Addresses                  |
  85  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  86  */
  87
  88 struct isis_fixed_hdr
  89 {
  90   u_char idrp;
  91   u_char length;
  92   u_char version1;
  93   u_char id_len;
  94   u_char pdu_type;
  95   u_char version2;
  96   u_char reserved;
  97   u_char max_area_addrs;
  98 } __attribute__ ((packed));
  99
 100 #define ISIS_FIXED_HDR_LEN 8
 101
 102 /*
 103  * IS-IS PDU types.
 104  */
 105
 106 #define L1_LAN_HELLO         15
 107 #define L2_LAN_HELLO         16
 108 /*
 109  *              L1 and L2 LAN IS to IS Hello PDU header
 110  * +-------+-------+-------+-------+-------+-------+-------+-------+
 111  * |                       Reserved                | Circuit Type  | 1
 112  * +-------+-------+-------+-------+-------+-------+-------+-------+
 113  * +                        Source ID                              + id_len
 114  * +-------+-------+-------+-------+-------+-------+-------+-------+
 115  * |                        Holding  Time                          | 2
 116  * +-------+-------+-------+-------+-------+-------+-------+-------+
 117  * |                        PDU Length                             | 2
 118  * +-------+-------+-------+-------+-------+-------+-------+-------+
 119  * |   R   |                Priority                               | 1
 120  * +-------+-------+-------+-------+-------+-------+-------+-------+
 121  * |                        LAN ID                                 | id_len + 1
 122  * +-------+-------+-------+-------+-------+-------+-------+-------+
 123  */
 124 struct isis_lan_hello_hdr
 125 {
 126   u_char circuit_t;
 127   u_char source_id[ISIS_SYS_ID_LEN];
 128   u_int16_t hold_time;
 129   u_int16_t pdu_len;
 130   u_char prio;
 131   u_char lan_id[ISIS_SYS_ID_LEN + 1];
 132 } __attribute__ ((packed));
 133 #define ISIS_LANHELLO_HDRLEN  19
 134
 135 #define P2P_HELLO            17
 136 /*
 137  *           Point-to-point IS to IS hello PDU header
 138  * +-------+-------+-------+-------+-------+-------+-------+-------+
 139  * |                        Reserved               | Circuit Type  | 1
 140  * +-------+-------+-------+-------+-------+-------+-------+-------+
 141  * +                        Source ID                              + id_len
 142  * +-------+-------+-------+-------+-------+-------+-------+-------+
 143  * +                        Holding  Time                          + 2
 144  * +-------+-------+-------+-------+-------+-------+-------+-------+
 145  * +                        PDU Length                             + 2
 146  * +-------+-------+-------+-------+-------+-------+-------+-------+
 147  * |                        Local Circuit ID                       | 1
 148  * +-------+-------+-------+-------+-------+-------+-------+-------+
 149  */
 150 struct isis_p2p_hello_hdr
 151 {
 152   u_char circuit_t;
 153   u_char source_id[ISIS_SYS_ID_LEN];
 154   u_int16_t hold_time;
 155   u_int16_t pdu_len;
 156   u_char local_id;
 157 } __attribute__ ((packed));
 158 #define ISIS_P2PHELLO_HDRLEN 12
 159
 160 #define L1_LINK_STATE        18
 161 #define L2_LINK_STATE        20
 162 /*
 163  *              L1 and L2 IS to IS link state PDU header
 164  * +-------+-------+-------+-------+-------+-------+-------+-------+
 165  * +                        PDU Length                             + 2
 166  * +-------+-------+-------+-------+-------+-------+-------+-------+
 167  * +                        Remaining Lifetime                     + 2
 168  * +-------+-------+-------+-------+-------+-------+-------+-------+
 169  * |                        LSP ID                                 | id_len + 2
 170  * +-------+-------+-------+-------+-------+-------+-------+-------+
 171  * +                        Sequence Number                        + 4
 172  * +-------+-------+-------+-------+-------+-------+-------+-------+
 173  * +                        Checksum                               + 2
 174  * +-------+-------+-------+-------+-------+-------+-------+-------+
 175  * |   P   |              ATT              |LSPDBOL|    ISTYPE     |
 176  * +-------+-------+-------+-------+-------+-------+-------+-------+
 177  */
 178 struct isis_link_state_hdr
 179 {
 180   u_int16_t pdu_len;
 181   u_int16_t rem_lifetime;
 182   u_char lsp_id[ISIS_SYS_ID_LEN + 2];
 183   u_int32_t seq_num;
 184   u_int16_t checksum;
 185   u_int8_t lsp_bits;
 186 } __attribute__ ((packed));
 187 #define ISIS_LSP_HDR_LEN 19
 188
 189 /*
 190  * Since the length field of LSP Entries TLV is one byte long, and each LSP
 191  * entry is LSP_ENTRIES_LEN (16) bytes long, the maximum number of LSP entries
 192  * can be accomodated in a TLV is
 193  * 255 / 16 = 15.
 194  *
 195  * Therefore, the maximum length of the LSP Entries TLV is
 196  * 16 * 15 + 2 (header) = 242 bytes.
 197  */
 198 #define MAX_LSP_ENTRIES_TLV_SIZE 242
 199
 200 #define L1_COMPLETE_SEQ_NUM  24
 201 #define L2_COMPLETE_SEQ_NUM  25
 202 /*
 203  *      L1 and L2 IS to IS complete sequence numbers PDU header
 204  * +-------+-------+-------+-------+-------+-------+-------+-------+
 205  * +                        PDU Length                             + 2
 206  * +-------+-------+-------+-------+-------+-------+-------+-------+
 207  * +                        Source ID                              + id_len + 1
 208  * +-------+-------+-------+-------+-------+-------+-------+-------+
 209  * +                        Start LSP ID                           + id_len + 2
 210  * +-------+-------+-------+-------+-------+-------+-------+-------+
 211  * +                        End LSP ID                             + id_len + 2
 212  * +-------+-------+-------+-------+-------+-------+-------+-------+
 213  */
 214 struct isis_complete_seqnum_hdr
 215 {
 216   u_int16_t pdu_len;
 217   u_char source_id[ISIS_SYS_ID_LEN + 1];
 218   u_char start_lsp_id[ISIS_SYS_ID_LEN + 2];
 219   u_char stop_lsp_id[ISIS_SYS_ID_LEN + 2];
 220 };
 221 #define ISIS_CSNP_HDRLEN 25
 222
 223 #define L1_PARTIAL_SEQ_NUM   26
 224 #define L2_PARTIAL_SEQ_NUM   27
 225 /*
 226  *      L1 and L2 IS to IS partial sequence numbers PDU header
 227  * +-------+-------+-------+-------+-------+-------+-------+-------+
 228  * +                        PDU Length                             + 2
 229  * +-------+-------+-------+-------+-------+-------+-------+-------+
 230  * +                        Source ID                              + id_len + 1
 231  * +---------------------------------------------------------------+
 232  */
 233 struct isis_partial_seqnum_hdr
 234 {
 235   u_int16_t pdu_len;
 236   u_char source_id[ISIS_SYS_ID_LEN + 1];
 237 };
 238 #define ISIS_PSNP_HDRLEN 9
 239
 240 #ifdef __SUNPRO_C
 241 #pragma pack()
 242 #endif
 243
 244 /*
 245  * Function for receiving IS-IS PDUs
 246  */
 247 int isis_receive (struct thread *thread);
 248
 249 /*
 250  * calling arguments for snp_process ()
 251  */
 252 #define ISIS_SNP_PSNP_FLAG 0
 253 #define ISIS_SNP_CSNP_FLAG 1
 254
 255 #define ISIS_AUTH_MD5_SIZE       16U
 256
 257 /*
 258  * Sending functions
 259  */
 260 int send_lan_l1_hello (struct thread *thread);
 261 int send_lan_l2_hello (struct thread *thread);
 262 int send_p2p_hello (struct thread *thread);
 263 int send_csnp (struct isis_circuit *circuit, int level);
 264 int send_l1_csnp (struct thread *thread);
 265 int send_l2_csnp (struct thread *thread);
 266 int send_l1_psnp (struct thread *thread);
 267 int send_l2_psnp (struct thread *thread);
 268 int send_lsp (struct thread *thread);
 269 int ack_lsp (struct isis_link_state_hdr *hdr,
 270              struct isis_circuit *circuit, int level);
 271 void fill_fixed_hdr (struct isis_fixed_hdr *hdr, u_char pdu_type);
 272 int send_hello (struct isis_circuit *circuit, int level);
 273
 274 #endif /* _ZEBRA_ISIS_PDU_H */