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 #define ISIS_FIXED_HDR_LEN 8
  69
  70 /*
  71  * IS-IS PDU types.
  72  */
  73
  74 #define L1_LAN_HELLO         15
  75 #define L2_LAN_HELLO         16
  76 /*
  77  *              L1 and L2 LAN IS to IS Hello PDU header
  78  * +-------+-------+-------+-------+-------+-------+-------+-------+
  79  * |                       Reserved                | Circuit Type  | 1
  80  * +-------+-------+-------+-------+-------+-------+-------+-------+
  81  * +                        Source ID                              + id_len
  82  * +-------+-------+-------+-------+-------+-------+-------+-------+
  83  * |                        Holding  Time                          | 2
  84  * +-------+-------+-------+-------+-------+-------+-------+-------+
  85  * |                        PDU Length                             | 2
  86  * +-------+-------+-------+-------+-------+-------+-------+-------+
  87  * |   R   |                Priority                               | 1
  88  * +-------+-------+-------+-------+-------+-------+-------+-------+
  89  * |                        LAN ID                                 | id_len + 1
  90  * +-------+-------+-------+-------+-------+-------+-------+-------+
  91  */
  92 struct isis_lan_hello_hdr {
  93         u_char circuit_t;
  94         u_char source_id[ISIS_SYS_ID_LEN];
  95         u_int16_t hold_time;
  96         u_int16_t pdu_len;
  97         u_char prio;
  98         u_char lan_id[ISIS_SYS_ID_LEN + 1];
  99 } __attribute__((packed));
 100 #define ISIS_LANHELLO_HDRLEN  19
 101
 102 #define P2P_HELLO            17
 103 /*
 104  *           Point-to-point IS to IS hello PDU header
 105  * +-------+-------+-------+-------+-------+-------+-------+-------+
 106  * |                        Reserved               | Circuit Type  | 1
 107  * +-------+-------+-------+-------+-------+-------+-------+-------+
 108  * +                        Source ID                              + id_len
 109  * +-------+-------+-------+-------+-------+-------+-------+-------+
 110  * +                        Holding  Time                          + 2
 111  * +-------+-------+-------+-------+-------+-------+-------+-------+
 112  * +                        PDU Length                             + 2
 113  * +-------+-------+-------+-------+-------+-------+-------+-------+
 114  * |                        Local Circuit ID                       | 1
 115  * +-------+-------+-------+-------+-------+-------+-------+-------+
 116  */
 117 struct isis_p2p_hello_hdr {
 118         u_char circuit_t;
 119         u_char source_id[ISIS_SYS_ID_LEN];
 120         u_int16_t hold_time;
 121         u_int16_t pdu_len;
 122         u_char local_id;
 123 } __attribute__((packed));
 124 #define ISIS_P2PHELLO_HDRLEN 12
 125
 126 #define L1_LINK_STATE        18
 127 #define L2_LINK_STATE        20
 128 struct isis_lsp_hdr {
 129         uint16_t pdu_len;
 130         uint16_t rem_lifetime;
 131         uint8_t lsp_id[ISIS_SYS_ID_LEN + 2];
 132         uint32_t seqno;
 133         uint16_t checksum;
 134         uint8_t lsp_bits;
 135 };
 136 #define ISIS_LSP_HDR_LEN 19
 137
 138 /*
 139  * Since the length field of LSP Entries TLV is one byte long, and each LSP
 140  * entry is LSP_ENTRIES_LEN (16) bytes long, the maximum number of LSP entries
 141  * can be accomodated in a TLV is
 142  * 255 / 16 = 15.
 143  *
 144  * Therefore, the maximum length of the LSP Entries TLV is
 145  * 16 * 15 + 2 (header) = 242 bytes.
 146  */
 147 #define MAX_LSP_ENTRIES_TLV_SIZE 242
 148
 149 #define L1_COMPLETE_SEQ_NUM  24
 150 #define L2_COMPLETE_SEQ_NUM  25
 151 /*
 152  *      L1 and L2 IS to IS complete sequence numbers PDU header
 153  * +-------+-------+-------+-------+-------+-------+-------+-------+
 154  * +                        PDU Length                             + 2
 155  * +-------+-------+-------+-------+-------+-------+-------+-------+
 156  * +                        Source ID                              + id_len + 1
 157  * +-------+-------+-------+-------+-------+-------+-------+-------+
 158  * +                        Start LSP ID                           + id_len + 2
 159  * +-------+-------+-------+-------+-------+-------+-------+-------+
 160  * +                        End LSP ID                             + id_len + 2
 161  * +-------+-------+-------+-------+-------+-------+-------+-------+
 162  */
 163 struct isis_complete_seqnum_hdr {
 164         u_int16_t pdu_len;
 165         u_char source_id[ISIS_SYS_ID_LEN + 1];
 166         u_char start_lsp_id[ISIS_SYS_ID_LEN + 2];
 167         u_char stop_lsp_id[ISIS_SYS_ID_LEN + 2];
 168 };
 169 #define ISIS_CSNP_HDRLEN 25
 170
 171 #define L1_PARTIAL_SEQ_NUM   26
 172 #define L2_PARTIAL_SEQ_NUM   27
 173 /*
 174  *      L1 and L2 IS to IS partial sequence numbers PDU header
 175  * +-------+-------+-------+-------+-------+-------+-------+-------+
 176  * +                        PDU Length                             + 2
 177  * +-------+-------+-------+-------+-------+-------+-------+-------+
 178  * +                        Source ID                              + id_len + 1
 179  * +---------------------------------------------------------------+
 180  */
 181 struct isis_partial_seqnum_hdr {
 182         u_int16_t pdu_len;
 183         u_char source_id[ISIS_SYS_ID_LEN + 1];
 184 };
 185 #define ISIS_PSNP_HDRLEN 9
 186
 187 #ifdef __SUNPRO_C
 188 #pragma pack()
 189 #endif
 190
 191 /*
 192  * Function for receiving IS-IS PDUs
 193  */
 194 int isis_receive(struct thread *thread);
 195
 196 /*
 197  * calling arguments for snp_process ()
 198  */
 199 #define ISIS_SNP_PSNP_FLAG 0
 200 #define ISIS_SNP_CSNP_FLAG 1
 201
 202 #define ISIS_AUTH_MD5_SIZE       16U
 203
 204 /*
 205  * Sending functions
 206  */
 207 int send_lan_l1_hello(struct thread *thread);
 208 int send_lan_l2_hello(struct thread *thread);
 209 int send_p2p_hello(struct thread *thread);
 210 int send_csnp(struct isis_circuit *circuit, int level);
 211 int send_l1_csnp(struct thread *thread);
 212 int send_l2_csnp(struct thread *thread);
 213 int send_l1_psnp(struct thread *thread);
 214 int send_l2_psnp(struct thread *thread);
 215 int send_lsp(struct thread *thread);
 216 void fill_fixed_hdr(uint8_t pdu_type, struct stream *stream);
 217 int send_hello(struct isis_circuit *circuit, int level);
 218
 219 #endif /* _ZEBRA_ISIS_PDU_H */