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; see the file COPYING; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 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         u_char idrp;
  54         u_char length;
  55         u_char version;
  56         u_char id_len;
  57         u_char pdu_type;
  58         u_int16_t holdtime;
  59         u_int16_t checksum;
  60 } __attribute__((packed));
  61
  62 #define ESIS_FIXED_HDR_LEN   9
  63
  64 #define ESH_PDU              2
  65 #define ISH_PDU              4
  66 #define RD_PDU               5
  67
  68 /*
  69  *                       IS to IS Fixed Header
  70  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  71  *  |         Intradomain Routeing Protocol Discriminator           |
  72  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  73  *  |                       Length Indicator                        |
  74  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  75  *  |                  Version/Protocol ID extension                |
  76  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  77  *  |   R   |   R   |   R   |              PDU Type                 |
  78  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  79  *  |                            Version                            |
  80  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  81  *  |                            Reserved                           |
  82  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  83  *  |                       Maximum Area Addresses                  |
  84  *  +-------+-------+-------+-------+-------+-------+-------+-------+
  85  */
  86
  87 struct isis_fixed_hdr {
  88         u_char idrp;
  89         u_char length;
  90         u_char version1;
  91         u_char id_len;
  92         u_char pdu_type;
  93         u_char version2;
  94         u_char reserved;
  95         u_char max_area_addrs;
  96 } __attribute__((packed));
  97
  98 #define ISIS_FIXED_HDR_LEN 8
  99
 100 /*
 101  * IS-IS PDU types.
 102  */
 103
 104 #define L1_LAN_HELLO         15
 105 #define L2_LAN_HELLO         16
 106 /*
 107  *              L1 and L2 LAN IS to IS Hello PDU header
 108  * +-------+-------+-------+-------+-------+-------+-------+-------+
 109  * |                       Reserved                | Circuit Type  | 1
 110  * +-------+-------+-------+-------+-------+-------+-------+-------+
 111  * +                        Source ID                              + id_len
 112  * +-------+-------+-------+-------+-------+-------+-------+-------+
 113  * |                        Holding  Time                          | 2
 114  * +-------+-------+-------+-------+-------+-------+-------+-------+
 115  * |                        PDU Length                             | 2
 116  * +-------+-------+-------+-------+-------+-------+-------+-------+
 117  * |   R   |                Priority                               | 1
 118  * +-------+-------+-------+-------+-------+-------+-------+-------+
 119  * |                        LAN ID                                 | id_len + 1
 120  * +-------+-------+-------+-------+-------+-------+-------+-------+
 121  */
 122 struct isis_lan_hello_hdr {
 123         u_char circuit_t;
 124         u_char source_id[ISIS_SYS_ID_LEN];
 125         u_int16_t hold_time;
 126         u_int16_t pdu_len;
 127         u_char prio;
 128         u_char lan_id[ISIS_SYS_ID_LEN + 1];
 129 } __attribute__((packed));
 130 #define ISIS_LANHELLO_HDRLEN  19
 131
 132 #define P2P_HELLO            17
 133 /*
 134  *           Point-to-point IS to IS hello PDU header
 135  * +-------+-------+-------+-------+-------+-------+-------+-------+
 136  * |                        Reserved               | Circuit Type  | 1
 137  * +-------+-------+-------+-------+-------+-------+-------+-------+
 138  * +                        Source ID                              + id_len
 139  * +-------+-------+-------+-------+-------+-------+-------+-------+
 140  * +                        Holding  Time                          + 2
 141  * +-------+-------+-------+-------+-------+-------+-------+-------+
 142  * +                        PDU Length                             + 2
 143  * +-------+-------+-------+-------+-------+-------+-------+-------+
 144  * |                        Local Circuit ID                       | 1
 145  * +-------+-------+-------+-------+-------+-------+-------+-------+
 146  */
 147 struct isis_p2p_hello_hdr {
 148         u_char circuit_t;
 149         u_char source_id[ISIS_SYS_ID_LEN];
 150         u_int16_t hold_time;
 151         u_int16_t pdu_len;
 152         u_char local_id;
 153 } __attribute__((packed));
 154 #define ISIS_P2PHELLO_HDRLEN 12
 155
 156 #define L1_LINK_STATE        18
 157 #define L2_LINK_STATE        20
 158 /*
 159  *              L1 and L2 IS to IS link state PDU header
 160  * +-------+-------+-------+-------+-------+-------+-------+-------+
 161  * +                        PDU Length                             + 2
 162  * +-------+-------+-------+-------+-------+-------+-------+-------+
 163  * +                        Remaining Lifetime                     + 2
 164  * +-------+-------+-------+-------+-------+-------+-------+-------+
 165  * |                        LSP ID                                 | id_len + 2
 166  * +-------+-------+-------+-------+-------+-------+-------+-------+
 167  * +                        Sequence Number                        + 4
 168  * +-------+-------+-------+-------+-------+-------+-------+-------+
 169  * +                        Checksum                               + 2
 170  * +-------+-------+-------+-------+-------+-------+-------+-------+
 171  * |   P   |              ATT              |LSPDBOL|    ISTYPE     |
 172  * +-------+-------+-------+-------+-------+-------+-------+-------+
 173  */
 174 struct isis_link_state_hdr {
 175         u_int16_t pdu_len;
 176         u_int16_t rem_lifetime;
 177         u_char lsp_id[ISIS_SYS_ID_LEN + 2];
 178         u_int32_t seq_num;
 179         u_int16_t checksum;
 180         u_int8_t lsp_bits;
 181 } __attribute__((packed));
 182 #define ISIS_LSP_HDR_LEN 19
 183
 184 /*
 185  * Since the length field of LSP Entries TLV is one byte long, and each LSP
 186  * entry is LSP_ENTRIES_LEN (16) bytes long, the maximum number of LSP entries
 187  * can be accomodated in a TLV is
 188  * 255 / 16 = 15.
 189  *
 190  * Therefore, the maximum length of the LSP Entries TLV is
 191  * 16 * 15 + 2 (header) = 242 bytes.
 192  */
 193 #define MAX_LSP_ENTRIES_TLV_SIZE 242
 194
 195 #define L1_COMPLETE_SEQ_NUM  24
 196 #define L2_COMPLETE_SEQ_NUM  25
 197 /*
 198  *      L1 and L2 IS to IS complete sequence numbers PDU header
 199  * +-------+-------+-------+-------+-------+-------+-------+-------+
 200  * +                        PDU Length                             + 2
 201  * +-------+-------+-------+-------+-------+-------+-------+-------+
 202  * +                        Source ID                              + id_len + 1
 203  * +-------+-------+-------+-------+-------+-------+-------+-------+
 204  * +                        Start LSP ID                           + id_len + 2
 205  * +-------+-------+-------+-------+-------+-------+-------+-------+
 206  * +                        End LSP ID                             + id_len + 2
 207  * +-------+-------+-------+-------+-------+-------+-------+-------+
 208  */
 209 struct isis_complete_seqnum_hdr {
 210         u_int16_t pdu_len;
 211         u_char source_id[ISIS_SYS_ID_LEN + 1];
 212         u_char start_lsp_id[ISIS_SYS_ID_LEN + 2];
 213         u_char stop_lsp_id[ISIS_SYS_ID_LEN + 2];
 214 };
 215 #define ISIS_CSNP_HDRLEN 25
 216
 217 #define L1_PARTIAL_SEQ_NUM   26
 218 #define L2_PARTIAL_SEQ_NUM   27
 219 /*
 220  *      L1 and L2 IS to IS partial sequence numbers PDU header
 221  * +-------+-------+-------+-------+-------+-------+-------+-------+
 222  * +                        PDU Length                             + 2
 223  * +-------+-------+-------+-------+-------+-------+-------+-------+
 224  * +                        Source ID                              + id_len + 1
 225  * +---------------------------------------------------------------+
 226  */
 227 struct isis_partial_seqnum_hdr {
 228         u_int16_t pdu_len;
 229         u_char source_id[ISIS_SYS_ID_LEN + 1];
 230 };
 231 #define ISIS_PSNP_HDRLEN 9
 232
 233 #ifdef __SUNPRO_C
 234 #pragma pack()
 235 #endif
 236
 237 /*
 238  * Function for receiving IS-IS PDUs
 239  */
 240 int isis_receive(struct thread *thread);
 241
 242 /*
 243  * calling arguments for snp_process ()
 244  */
 245 #define ISIS_SNP_PSNP_FLAG 0
 246 #define ISIS_SNP_CSNP_FLAG 1
 247
 248 #define ISIS_AUTH_MD5_SIZE       16U
 249
 250 /*
 251  * Sending functions
 252  */
 253 int send_lan_l1_hello(struct thread *thread);
 254 int send_lan_l2_hello(struct thread *thread);
 255 int send_p2p_hello(struct thread *thread);
 256 int send_csnp(struct isis_circuit *circuit, int level);
 257 int send_l1_csnp(struct thread *thread);
 258 int send_l2_csnp(struct thread *thread);
 259 int send_l1_psnp(struct thread *thread);
 260 int send_l2_psnp(struct thread *thread);
 261 int send_lsp(struct thread *thread);
 262 int ack_lsp(struct isis_link_state_hdr *hdr, struct isis_circuit *circuit,
 263             int level);
 264 void fill_fixed_hdr(struct isis_fixed_hdr *hdr, u_char pdu_type);
 265 int send_hello(struct isis_circuit *circuit, int level);
 266
 267 #endif /* _ZEBRA_ISIS_PDU_H */