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 /* 78 * L2TPv2 Message Type 79 */ 80 #define RTE_L2TPV2_MSG_TYPE_CONTROL 0xC802 81 #define RTE_L2TPV2_MSG_TYPE_DATA 0x0002 82 #define RTE_L2TPV2_MSG_TYPE_DATA_L 0x4002 83 #define RTE_L2TPV2_MSG_TYPE_DATA_S 0x0802 84 #define RTE_L2TPV2_MSG_TYPE_DATA_O 0x0202 85 #define RTE_L2TPV2_MSG_TYPE_DATA_L_S 0x4802 86 #define RTE_L2TPV2_MSG_TYPE_DATA_L_O 0x4202 87 #define RTE_L2TPV2_MSG_TYPE_DATA_S_O 0x0A02 88 #define RTE_L2TPV2_MSG_TYPE_DATA_L_S_O 0x4A02 89 90 /** 91 * L2TPv2 Common Header 92 */ 93 struct rte_l2tpv2_common_hdr { 94 union { 95 /** header flags and protocol version */ 96 rte_be16_t flags_version; 97 __extension__ 98 struct { 99 #if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN 100 uint16_t ver:4; /**< protocol version */ 101 uint16_t res3:4; /**< reserved */ 102 uint16_t p:1; /**< priority option bit */ 103 uint16_t o:1; /**< offset option bit */ 104 uint16_t res2:1; /**< reserved */ 105 uint16_t s:1; /**< ns/nr option bit */ 106 uint16_t res1:2; /**< reserved */ 107 uint16_t l:1; /**< length option bit */ 108 uint16_t t:1; /**< message Type */ 109 #elif RTE_BYTE_ORDER == RTE_BIG_ENDIAN 110 uint16_t t:1; /**< message Type */ 111 uint16_t l:1; /**< length option bit */ 112 uint16_t res1:2; /**< reserved */ 113 uint16_t s:1; /**< ns/nr option bit */ 114 uint16_t res2:1; /**< reserved */ 115 uint16_t o:1; /**< offset option bit */ 116 uint16_t p:1; /**< priority option bit */ 117 uint16_t res3:4; /**< reserved */ 118 uint16_t ver:4; /**< protocol version */ 119 #endif 120 }; 121 }; 122 }; 123 124 /** 125 * L2TPv2 message Header contains all options(length, ns, nr, 126 * offset size, offset padding). 127 */ 128 struct __rte_packed_begin rte_l2tpv2_msg_with_all_options { 129 rte_be16_t length; /**< length(16) */ 130 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 131 rte_be16_t session_id; /**< session ID(16) */ 132 rte_be16_t ns; /**< Ns(16) */ 133 rte_be16_t nr; /**< Nr(16) */ 134 rte_be16_t offset_size; /**< offset size(16) */ 135 uint8_t *offset_padding; /**< offset padding(variable length) */ 136 } __rte_packed_end; 137 138 /** 139 * L2TPv2 message Header contains all options except length(ns, nr, 140 * offset size, offset padding). 141 */ 142 struct __rte_packed_begin rte_l2tpv2_msg_without_length { 143 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 144 rte_be16_t session_id; /**< session ID(16) */ 145 rte_be16_t ns; /**< Ns(16) */ 146 rte_be16_t nr; /**< Nr(16) */ 147 rte_be16_t offset_size; /**< offset size(16) */ 148 uint8_t *offset_padding; /**< offset padding(variable length) */ 149 } __rte_packed_end; 150 151 /** 152 * L2TPv2 message Header contains all options except ns_nr(length, 153 * offset size, offset padding). 154 * Ns and Nr MUST be together. 155 */ 156 struct rte_l2tpv2_msg_without_ns_nr { 157 rte_be16_t length; /**< length(16) */ 158 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 159 rte_be16_t session_id; /**< session ID(16) */ 160 rte_be16_t offset_size; /**< offset size(16) */ 161 uint8_t *offset_padding; /**< offset padding(variable length) */ 162 }; 163 164 /** 165 * L2TPv2 message Header contains all options except ns_nr(length, ns, nr). 166 * offset size and offset padding MUST be together. 167 */ 168 struct rte_l2tpv2_msg_without_offset { 169 rte_be16_t length; /**< length(16) */ 170 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 171 rte_be16_t session_id; /**< session ID(16) */ 172 rte_be16_t ns; /**< Ns(16) */ 173 rte_be16_t nr; /**< Nr(16) */ 174 }; 175 176 /** 177 * L2TPv2 message Header contains options offset size and offset padding. 178 */ 179 struct __rte_packed_begin rte_l2tpv2_msg_with_offset { 180 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 181 rte_be16_t session_id; /**< session ID(16) */ 182 rte_be16_t offset_size; /**< offset size(16) */ 183 uint8_t *offset_padding; /**< offset padding(variable length) */ 184 } __rte_packed_end; 185 186 /** 187 * L2TPv2 message Header contains options ns and nr. 188 */ 189 struct rte_l2tpv2_msg_with_ns_nr { 190 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 191 rte_be16_t session_id; /**< session ID(16) */ 192 rte_be16_t ns; /**< Ns(16) */ 193 rte_be16_t nr; /**< Nr(16) */ 194 }; 195 196 /** 197 * L2TPv2 message Header contains option length. 198 */ 199 struct rte_l2tpv2_msg_with_length { 200 rte_be16_t length; /**< length(16) */ 201 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 202 rte_be16_t session_id; /**< session ID(16) */ 203 }; 204 205 /** 206 * L2TPv2 message Header without all options. 207 */ 208 struct rte_l2tpv2_msg_without_all_options { 209 rte_be16_t tunnel_id; /**< tunnel ID(16) */ 210 rte_be16_t session_id; /**< session ID(16) */ 211 }; 212 213 /** 214 * L2TPv2 Combined Message Header Format: Common Header + Options 215 */ 216 struct __rte_packed_begin rte_l2tpv2_combined_msg_hdr { 217 struct rte_l2tpv2_common_hdr common; /**< common header */ 218 union { 219 /** header with all options */ 220 struct rte_l2tpv2_msg_with_all_options type0; 221 /** header with all options except length */ 222 struct rte_l2tpv2_msg_without_length type1; 223 /** header with all options except ns/nr */ 224 struct rte_l2tpv2_msg_without_ns_nr type2; 225 /** header with all options except offset */ 226 struct rte_l2tpv2_msg_without_offset type3; 227 /** header with offset options */ 228 struct rte_l2tpv2_msg_with_offset type4; 229 /** header with ns/nr options */ 230 struct rte_l2tpv2_msg_with_ns_nr type5; 231 /** header with length option */ 232 struct rte_l2tpv2_msg_with_length type6; 233 /** header without all options */ 234 struct rte_l2tpv2_msg_without_all_options type7; 235 }; 236 } __rte_packed_end; 237 238 #endif /* _RTE_L2TPV2_H_ */ 239