1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2021 Intel Corporation. 3 */ 4 5 #ifndef _RTE_L2TPV2_H_ 6 #define _RTE_L2TPV2_H_ 7 8 /** 9 * @file 10 * 11 * L2TP header: 12 * 13 * `-0--------------------1----------------2-------------------3` 14 * 15 * `-0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1` 16 * 17 * `+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+` 18 * 19 * `|T|L|x|x|S|x|O|P|x|x|x|x|--Ver--|-----------Length (opt)--------|` 20 * 21 * `+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+` 22 * 23 * `|-----------Tunnel ID-----------|-----------Session ID----------|` 24 * 25 * `+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+` 26 * 27 * `|-----------Ns (opt)------------|-----------Nr (opt)------------|` 28 * 29 * `+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+` 30 * 31 * `|---------Offset Size (opt)-----|---------Offset pad... (opt)` 32 * 33 * `+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+` 34 * 35 * The Type (T) bit indicates the type of message. It is set to 0 for a data 36 * message and 1 for a control message. 37 * 38 * If the Length (L) bit is 1, the Length field is present. This bit MUST be 39 * set to 1 for control messages. 40 * 41 * The x bits are reserved for future extensions. All reserved bits MUST 42 * be set to 0 on outgoing messages and ignored on incoming messages. 43 * 44 * If the Sequence (S) bit is set to 1 the Ns and Nr fields are present. 45 * The S bit MUST be set to 1 for control messages. 46 * 47 * If the Offset (O) bit is 1, the Offset Size field is present. The O 48 * bit MUST be set to 0 for control messages. 49 * 50 * If the Priority (P) bit is 1, this data message should receive 51 * preferential treatment in its local queuing and transmission. 52 * The P bit MUST be set to 0 for control messages. 53 * 54 * Ver MUST be 2, indicating the version of the L2TP data message header. 55 * 56 * The Length field indicates the total length of the message in octets. 57 * 58 * Tunnel ID indicates the identifier for the control connection. 59 * 60 * Session ID indicates the identifier for a session within a tunnel. 61 * 62 * Ns indicates the sequence number for this data or control message. 63 * 64 * Nr indicates the sequence number expected in the next control message 65 * to be received. 66 * 67 * The Offset Size field, if present, specifies the number of octets 68 * past the L2TP header at which the payload data is expected to start. 69 * Actual data within the offset padding is undefined. If the offset 70 * field is present, the L2TP header ends after the last octet of the 71 * offset padding. 72 */ 73 74 #include <stdint.h> 75 #include <rte_byteorder.h> 76 77 #ifdef __cplusplus 78 extern "C" { 79 #endif 80 81 /** 82 * L2TPv2 Common Header 83 */ 84 RTE_STD_C11 85 struct rte_l2tpv2_common_hdr { 86 union { 87 /** header flags and protocol version */ 88 rte_be16_t flags_version; 89 __extension__ 90 struct { 91 #if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN 92 uint16_t t:1; /**< message Type */ 93 uint16_t l:1; /**< length option bit */ 94 uint16_t res1:2; /**< reserved */ 95 uint16_t s:1; /**< ns/nr option bit */ 96 uint16_t res2:1; /**< reserved */ 97 uint16_t o:1; /**< offset option bit */ 98 uint16_t p:1; /**< priority option bit */ 99 uint16_t res3:4; /**< reserved */ 100 uint16_t ver:4; /**< protocol version */ 101 #elif RTE_BYTE_ORDER == RTE_BIG_ENDIAN 102 uint16_t ver:4; /**< protocol version */ 103 uint16_t res3:4; /**< reserved */ 104 uint16_t p:1; /**< priority option bit */ 105 uint16_t o:1; /**< offset option bit */ 106 uint16_t res2:1; /**< reserved */ 107 uint16_t s:1; /**< ns/nr option bit */ 108 uint16_t res1:2; /**< reserved */ 109 uint16_t l:1; /**< length option bit */ 110 uint16_t t:1; /**< message Type */ 111 #endif 112 }; 113 }; 114 }; 115 116 /** 117 * L2TPv2 message Header contains all options(length, ns, nr, 118 * offset size, offset padding). 119 */ 120 struct rte_l2tpv2_msg_with_all_options { 121 rte_be16_t length; /**< length(16) */ 122 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 123 rte_be16_t session_id; /**< session ID(16) */ 124 rte_be16_t ns; /**< Ns(16) */ 125 rte_be16_t nr; /**< Nr(16) */ 126 rte_be16_t offset_size; /**< offset size(16) */ 127 uint8_t *offset_padding; /**< offset padding(variable length) */ 128 } __rte_packed; 129 130 /** 131 * L2TPv2 message Header contains all options except length(ns, nr, 132 * offset size, offset padding). 133 */ 134 struct rte_l2tpv2_msg_without_length { 135 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 136 rte_be16_t session_id; /**< session ID(16) */ 137 rte_be16_t ns; /**< Ns(16) */ 138 rte_be16_t nr; /**< Nr(16) */ 139 rte_be16_t offset_size; /**< offset size(16) */ 140 uint8_t *offset_padding; /**< offset padding(variable length) */ 141 } __rte_packed; 142 143 /** 144 * L2TPv2 message Header contains all options except ns_nr(length, 145 * offset size, offset padding). 146 * Ns and Nr MUST be toghter. 147 */ 148 struct rte_l2tpv2_msg_without_ns_nr { 149 rte_be16_t length; /**< length(16) */ 150 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 151 rte_be16_t session_id; /**< session ID(16) */ 152 rte_be16_t offset_size; /**< offset size(16) */ 153 uint8_t *offset_padding; /**< offset padding(variable length) */ 154 }; 155 156 /** 157 * L2TPv2 message Header contains all options except ns_nr(length, ns, nr). 158 * offset size and offset padding MUST be toghter. 159 */ 160 struct rte_l2tpv2_msg_without_offset { 161 rte_be16_t length; /**< length(16) */ 162 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 163 rte_be16_t session_id; /**< session ID(16) */ 164 rte_be16_t ns; /**< Ns(16) */ 165 rte_be16_t nr; /**< Nr(16) */ 166 }; 167 168 /** 169 * L2TPv2 message Header contains options offset size and offset padding. 170 */ 171 struct rte_l2tpv2_msg_with_offset { 172 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 173 rte_be16_t session_id; /**< session ID(16) */ 174 rte_be16_t offset_size; /**< offset size(16) */ 175 uint8_t *offset_padding; /**< offset padding(variable length) */ 176 } __rte_packed; 177 178 /** 179 * L2TPv2 message Header contains options ns and nr. 180 */ 181 struct rte_l2tpv2_msg_with_ns_nr { 182 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 183 rte_be16_t session_id; /**< session ID(16) */ 184 rte_be16_t ns; /**< Ns(16) */ 185 rte_be16_t nr; /**< Nr(16) */ 186 }; 187 188 /** 189 * L2TPv2 message Header contains option length. 190 */ 191 struct rte_l2tpv2_msg_with_length { 192 rte_be16_t length; /**< length(16) */ 193 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 194 rte_be16_t session_id; /**< session ID(16) */ 195 }; 196 197 /** 198 * L2TPv2 message Header without all options. 199 */ 200 struct rte_l2tpv2_msg_without_all_options { 201 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 202 rte_be16_t session_id; /**< session ID(16) */ 203 }; 204 205 /** 206 * L2TPv2 Combined Message Header Format: Common Header + Options 207 */ 208 RTE_STD_C11 209 struct rte_l2tpv2_combined_msg_hdr { 210 struct rte_l2tpv2_common_hdr common; /**< common header */ 211 union { 212 /** header with all options */ 213 struct rte_l2tpv2_msg_with_all_options type0; 214 /** header with all options except length */ 215 struct rte_l2tpv2_msg_without_length type1; 216 /** header with all options except ns/nr */ 217 struct rte_l2tpv2_msg_without_ns_nr type2; 218 /** header with all options except offset */ 219 struct rte_l2tpv2_msg_without_offset type3; 220 /** header with offset options */ 221 struct rte_l2tpv2_msg_with_offset type4; 222 /** header with ns/nr options */ 223 struct rte_l2tpv2_msg_with_ns_nr type5; 224 /** header with length option */ 225 struct rte_l2tpv2_msg_with_length type6; 226 /** header without all options */ 227 struct rte_l2tpv2_msg_without_all_options type7; 228 }; 229 } __rte_packed; 230 231 #ifdef __cplusplus 232 } 233 #endif 234 235 #endif /* _RTE_L2TPV2_H_ */ 236