| 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| 2 | /* |
| 3 | * An interface between IEEE802.15.4 device and rest of the kernel. |
| 4 | * |
| 5 | * Copyright (C) 2007-2012 Siemens AG |
| 6 | * |
| 7 | * Written by: |
| 8 | * Pavel Smolenskiy <pavel.smolenskiy@gmail.com> |
| 9 | * Maxim Gorbachyov <maxim.gorbachev@siemens.com> |
| 10 | * Maxim Osipov <maxim.osipov@siemens.com> |
| 11 | * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> |
| 12 | * Alexander Smirnov <alex.bluesman.smirnov@gmail.com> |
| 13 | */ |
| 14 | |
| 15 | #ifndef IEEE802154_NETDEVICE_H |
| 16 | #define IEEE802154_NETDEVICE_H |
| 17 | |
| 18 | #define IEEE802154_REQUIRED_SIZE(struct_type, member) \ |
| 19 | (offsetof(typeof(struct_type), member) + \ |
| 20 | sizeof(((typeof(struct_type) *)(NULL))->member)) |
| 21 | |
| 22 | #define IEEE802154_ADDR_OFFSET \ |
| 23 | offsetof(typeof(struct sockaddr_ieee802154), addr) |
| 24 | |
| 25 | #define IEEE802154_MIN_NAMELEN (IEEE802154_ADDR_OFFSET + \ |
| 26 | IEEE802154_REQUIRED_SIZE(struct ieee802154_addr_sa, addr_type)) |
| 27 | |
| 28 | #define IEEE802154_NAMELEN_SHORT (IEEE802154_ADDR_OFFSET + \ |
| 29 | IEEE802154_REQUIRED_SIZE(struct ieee802154_addr_sa, short_addr)) |
| 30 | |
| 31 | #define IEEE802154_NAMELEN_LONG (IEEE802154_ADDR_OFFSET + \ |
| 32 | IEEE802154_REQUIRED_SIZE(struct ieee802154_addr_sa, hwaddr)) |
| 33 | |
| 34 | #include <net/af_ieee802154.h> |
| 35 | #include <linux/netdevice.h> |
| 36 | #include <linux/skbuff.h> |
| 37 | #include <linux/ieee802154.h> |
| 38 | |
| 39 | #include <net/cfg802154.h> |
| 40 | |
| 41 | struct ieee802154_beacon_hdr { |
| 42 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
| 43 | u16 beacon_order:4, |
| 44 | superframe_order:4, |
| 45 | final_cap_slot:4, |
| 46 | battery_life_ext:1, |
| 47 | reserved0:1, |
| 48 | pan_coordinator:1, |
| 49 | assoc_permit:1; |
| 50 | u8 gts_count:3, |
| 51 | gts_reserved:4, |
| 52 | gts_permit:1; |
| 53 | u8 pend_short_addr_count:3, |
| 54 | reserved1:1, |
| 55 | pend_ext_addr_count:3, |
| 56 | reserved2:1; |
| 57 | #elif defined(__BIG_ENDIAN_BITFIELD) |
| 58 | u16 assoc_permit:1, |
| 59 | pan_coordinator:1, |
| 60 | reserved0:1, |
| 61 | battery_life_ext:1, |
| 62 | final_cap_slot:4, |
| 63 | superframe_order:4, |
| 64 | beacon_order:4; |
| 65 | u8 gts_permit:1, |
| 66 | gts_reserved:4, |
| 67 | gts_count:3; |
| 68 | u8 reserved2:1, |
| 69 | pend_ext_addr_count:3, |
| 70 | reserved1:1, |
| 71 | pend_short_addr_count:3; |
| 72 | #else |
| 73 | #error "Please fix <asm/byteorder.h>" |
| 74 | #endif |
| 75 | } __packed; |
| 76 | |
| 77 | struct ieee802154_mac_cmd_pl { |
| 78 | u8 cmd_id; |
| 79 | } __packed; |
| 80 | |
| 81 | struct ieee802154_sechdr { |
| 82 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
| 83 | u8 level:3, |
| 84 | key_id_mode:2, |
| 85 | reserved:3; |
| 86 | #elif defined(__BIG_ENDIAN_BITFIELD) |
| 87 | u8 reserved:3, |
| 88 | key_id_mode:2, |
| 89 | level:3; |
| 90 | #else |
| 91 | #error "Please fix <asm/byteorder.h>" |
| 92 | #endif |
| 93 | u8 key_id; |
| 94 | __le32 frame_counter; |
| 95 | union { |
| 96 | __le32 short_src; |
| 97 | __le64 extended_src; |
| 98 | }; |
| 99 | }; |
| 100 | |
| 101 | struct ieee802154_hdr_fc { |
| 102 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
| 103 | u16 type:3, |
| 104 | security_enabled:1, |
| 105 | frame_pending:1, |
| 106 | ack_request:1, |
| 107 | intra_pan:1, |
| 108 | reserved:3, |
| 109 | dest_addr_mode:2, |
| 110 | version:2, |
| 111 | source_addr_mode:2; |
| 112 | #elif defined(__BIG_ENDIAN_BITFIELD) |
| 113 | u16 reserved:1, |
| 114 | intra_pan:1, |
| 115 | ack_request:1, |
| 116 | frame_pending:1, |
| 117 | security_enabled:1, |
| 118 | type:3, |
| 119 | source_addr_mode:2, |
| 120 | version:2, |
| 121 | dest_addr_mode:2, |
| 122 | reserved2:2; |
| 123 | #else |
| 124 | #error "Please fix <asm/byteorder.h>" |
| 125 | #endif |
| 126 | }; |
| 127 | |
| 128 | struct ieee802154_assoc_req_pl { |
| 129 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
| 130 | u8 reserved1:1, |
| 131 | device_type:1, |
| 132 | power_source:1, |
| 133 | rx_on_when_idle:1, |
| 134 | assoc_type:1, |
| 135 | reserved2:1, |
| 136 | security_cap:1, |
| 137 | alloc_addr:1; |
| 138 | #elif defined(__BIG_ENDIAN_BITFIELD) |
| 139 | u8 alloc_addr:1, |
| 140 | security_cap:1, |
| 141 | reserved2:1, |
| 142 | assoc_type:1, |
| 143 | rx_on_when_idle:1, |
| 144 | power_source:1, |
| 145 | device_type:1, |
| 146 | reserved1:1; |
| 147 | #else |
| 148 | #error "Please fix <asm/byteorder.h>" |
| 149 | #endif |
| 150 | } __packed; |
| 151 | |
| 152 | struct ieee802154_assoc_resp_pl { |
| 153 | __le16 short_addr; |
| 154 | u8 status; |
| 155 | } __packed; |
| 156 | |
| 157 | enum ieee802154_frame_version { |
| 158 | IEEE802154_2003_STD, |
| 159 | IEEE802154_2006_STD, |
| 160 | IEEE802154_STD, |
| 161 | IEEE802154_RESERVED_STD, |
| 162 | IEEE802154_MULTIPURPOSE_STD = IEEE802154_2003_STD, |
| 163 | }; |
| 164 | |
| 165 | enum ieee802154_addressing_mode { |
| 166 | IEEE802154_NO_ADDRESSING, |
| 167 | IEEE802154_RESERVED, |
| 168 | IEEE802154_SHORT_ADDRESSING, |
| 169 | IEEE802154_EXTENDED_ADDRESSING, |
| 170 | }; |
| 171 | |
| 172 | enum ieee802154_association_status { |
| 173 | IEEE802154_ASSOCIATION_SUCCESSFUL = 0x00, |
| 174 | IEEE802154_PAN_AT_CAPACITY = 0x01, |
| 175 | IEEE802154_PAN_ACCESS_DENIED = 0x02, |
| 176 | IEEE802154_HOPPING_SEQUENCE_OFFSET_DUP = 0x03, |
| 177 | IEEE802154_FAST_ASSOCIATION_SUCCESSFUL = 0x80, |
| 178 | }; |
| 179 | |
| 180 | enum ieee802154_disassociation_reason { |
| 181 | IEEE802154_COORD_WISHES_DEVICE_TO_LEAVE = 0x1, |
| 182 | IEEE802154_DEVICE_WISHES_TO_LEAVE = 0x2, |
| 183 | }; |
| 184 | |
| 185 | struct ieee802154_hdr { |
| 186 | struct ieee802154_hdr_fc fc; |
| 187 | u8 seq; |
| 188 | struct ieee802154_addr source; |
| 189 | struct ieee802154_addr dest; |
| 190 | struct ieee802154_sechdr sec; |
| 191 | }; |
| 192 | |
| 193 | struct ieee802154_beacon_frame { |
| 194 | struct ieee802154_hdr mhr; |
| 195 | struct ieee802154_beacon_hdr mac_pl; |
| 196 | }; |
| 197 | |
| 198 | struct ieee802154_mac_cmd_frame { |
| 199 | struct ieee802154_hdr mhr; |
| 200 | struct ieee802154_mac_cmd_pl mac_pl; |
| 201 | }; |
| 202 | |
| 203 | struct ieee802154_beacon_req_frame { |
| 204 | struct ieee802154_hdr mhr; |
| 205 | struct ieee802154_mac_cmd_pl mac_pl; |
| 206 | }; |
| 207 | |
| 208 | struct ieee802154_association_req_frame { |
| 209 | struct ieee802154_hdr mhr; |
| 210 | struct ieee802154_mac_cmd_pl mac_pl; |
| 211 | struct ieee802154_assoc_req_pl assoc_req_pl; |
| 212 | }; |
| 213 | |
| 214 | struct ieee802154_association_resp_frame { |
| 215 | struct ieee802154_hdr mhr; |
| 216 | struct ieee802154_mac_cmd_pl mac_pl; |
| 217 | struct ieee802154_assoc_resp_pl assoc_resp_pl; |
| 218 | }; |
| 219 | |
| 220 | struct ieee802154_disassociation_notif_frame { |
| 221 | struct ieee802154_hdr mhr; |
| 222 | struct ieee802154_mac_cmd_pl mac_pl; |
| 223 | u8 disassoc_pl; |
| 224 | }; |
| 225 | |
| 226 | /* pushes hdr onto the skb. fields of hdr->fc that can be calculated from |
| 227 | * the contents of hdr will be, and the actual value of those bits in |
| 228 | * hdr->fc will be ignored. this includes the INTRA_PAN bit and the frame |
| 229 | * version, if SECEN is set. |
| 230 | */ |
| 231 | int ieee802154_hdr_push(struct sk_buff *skb, struct ieee802154_hdr *hdr); |
| 232 | |
| 233 | /* pulls the entire 802.15.4 header off of the skb, including the security |
| 234 | * header, and performs pan id decompression |
| 235 | */ |
| 236 | int ieee802154_hdr_pull(struct sk_buff *skb, struct ieee802154_hdr *hdr); |
| 237 | |
| 238 | /* parses the frame control, sequence number of address fields in a given skb |
| 239 | * and stores them into hdr, performing pan id decompression and length checks |
| 240 | * to be suitable for use in header_ops.parse |
| 241 | */ |
| 242 | int ieee802154_hdr_peek_addrs(const struct sk_buff *skb, |
| 243 | struct ieee802154_hdr *hdr); |
| 244 | |
| 245 | /* parses the full 802.15.4 header a given skb and stores them into hdr, |
| 246 | * performing pan id decompression and length checks to be suitable for use in |
| 247 | * header_ops.parse |
| 248 | */ |
| 249 | int ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr); |
| 250 | |
| 251 | /* pushes/pulls various frame types into/from an skb */ |
| 252 | int ieee802154_beacon_push(struct sk_buff *skb, |
| 253 | struct ieee802154_beacon_frame *beacon); |
| 254 | int ieee802154_mac_cmd_push(struct sk_buff *skb, void *frame, |
| 255 | const void *pl, unsigned int pl_len); |
| 256 | int ieee802154_mac_cmd_pl_pull(struct sk_buff *skb, |
| 257 | struct ieee802154_mac_cmd_pl *mac_pl); |
| 258 | |
| 259 | int ieee802154_max_payload(const struct ieee802154_hdr *hdr); |
| 260 | |
| 261 | static inline int |
| 262 | ieee802154_sechdr_authtag_len(const struct ieee802154_sechdr *sec) |
| 263 | { |
| 264 | switch (sec->level) { |
| 265 | case IEEE802154_SCF_SECLEVEL_MIC32: |
| 266 | case IEEE802154_SCF_SECLEVEL_ENC_MIC32: |
| 267 | return 4; |
| 268 | case IEEE802154_SCF_SECLEVEL_MIC64: |
| 269 | case IEEE802154_SCF_SECLEVEL_ENC_MIC64: |
| 270 | return 8; |
| 271 | case IEEE802154_SCF_SECLEVEL_MIC128: |
| 272 | case IEEE802154_SCF_SECLEVEL_ENC_MIC128: |
| 273 | return 16; |
| 274 | case IEEE802154_SCF_SECLEVEL_NONE: |
| 275 | case IEEE802154_SCF_SECLEVEL_ENC: |
| 276 | default: |
| 277 | return 0; |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | static inline int ieee802154_hdr_length(struct sk_buff *skb) |
| 282 | { |
| 283 | struct ieee802154_hdr hdr; |
| 284 | int len = ieee802154_hdr_pull(skb, hdr: &hdr); |
| 285 | |
| 286 | if (len > 0) |
| 287 | skb_push(skb, len); |
| 288 | |
| 289 | return len; |
| 290 | } |
| 291 | |
| 292 | static inline bool ieee802154_addr_equal(const struct ieee802154_addr *a1, |
| 293 | const struct ieee802154_addr *a2) |
| 294 | { |
| 295 | if (a1->pan_id != a2->pan_id || a1->mode != a2->mode) |
| 296 | return false; |
| 297 | |
| 298 | if ((a1->mode == IEEE802154_ADDR_LONG && |
| 299 | a1->extended_addr != a2->extended_addr) || |
| 300 | (a1->mode == IEEE802154_ADDR_SHORT && |
| 301 | a1->short_addr != a2->short_addr)) |
| 302 | return false; |
| 303 | |
| 304 | return true; |
| 305 | } |
| 306 | |
| 307 | static inline __le64 ieee802154_devaddr_from_raw(const void *raw) |
| 308 | { |
| 309 | u64 temp; |
| 310 | |
| 311 | memcpy(&temp, raw, IEEE802154_ADDR_LEN); |
| 312 | return (__force __le64)swab64(temp); |
| 313 | } |
| 314 | |
| 315 | static inline void ieee802154_devaddr_to_raw(void *raw, __le64 addr) |
| 316 | { |
| 317 | u64 temp = swab64((__force u64)addr); |
| 318 | |
| 319 | memcpy(raw, &temp, IEEE802154_ADDR_LEN); |
| 320 | } |
| 321 | |
| 322 | static inline int |
| 323 | ieee802154_sockaddr_check_size(struct sockaddr_ieee802154 *daddr, int len) |
| 324 | { |
| 325 | struct ieee802154_addr_sa *sa; |
| 326 | int ret = 0; |
| 327 | |
| 328 | sa = &daddr->addr; |
| 329 | if (len < IEEE802154_MIN_NAMELEN) |
| 330 | return -EINVAL; |
| 331 | switch (sa->addr_type) { |
| 332 | case IEEE802154_ADDR_NONE: |
| 333 | break; |
| 334 | case IEEE802154_ADDR_SHORT: |
| 335 | if (len < IEEE802154_NAMELEN_SHORT) |
| 336 | ret = -EINVAL; |
| 337 | break; |
| 338 | case IEEE802154_ADDR_LONG: |
| 339 | if (len < IEEE802154_NAMELEN_LONG) |
| 340 | ret = -EINVAL; |
| 341 | break; |
| 342 | default: |
| 343 | ret = -EINVAL; |
| 344 | break; |
| 345 | } |
| 346 | return ret; |
| 347 | } |
| 348 | |
| 349 | static inline void ieee802154_addr_from_sa(struct ieee802154_addr *a, |
| 350 | const struct ieee802154_addr_sa *sa) |
| 351 | { |
| 352 | a->mode = sa->addr_type; |
| 353 | a->pan_id = cpu_to_le16(sa->pan_id); |
| 354 | |
| 355 | switch (a->mode) { |
| 356 | case IEEE802154_ADDR_SHORT: |
| 357 | a->short_addr = cpu_to_le16(sa->short_addr); |
| 358 | break; |
| 359 | case IEEE802154_ADDR_LONG: |
| 360 | a->extended_addr = ieee802154_devaddr_from_raw(raw: sa->hwaddr); |
| 361 | break; |
| 362 | } |
| 363 | } |
| 364 | |
| 365 | static inline void ieee802154_addr_to_sa(struct ieee802154_addr_sa *sa, |
| 366 | const struct ieee802154_addr *a) |
| 367 | { |
| 368 | sa->addr_type = a->mode; |
| 369 | sa->pan_id = le16_to_cpu(a->pan_id); |
| 370 | |
| 371 | switch (a->mode) { |
| 372 | case IEEE802154_ADDR_SHORT: |
| 373 | sa->short_addr = le16_to_cpu(a->short_addr); |
| 374 | break; |
| 375 | case IEEE802154_ADDR_LONG: |
| 376 | ieee802154_devaddr_to_raw(raw: sa->hwaddr, addr: a->extended_addr); |
| 377 | break; |
| 378 | } |
| 379 | } |
| 380 | |
| 381 | /* |
| 382 | * A control block of skb passed between the ARPHRD_IEEE802154 device |
| 383 | * and other stack parts. |
| 384 | */ |
| 385 | struct ieee802154_mac_cb { |
| 386 | u8 lqi; |
| 387 | u8 type; |
| 388 | bool ackreq; |
| 389 | bool secen; |
| 390 | bool secen_override; |
| 391 | u8 seclevel; |
| 392 | bool seclevel_override; |
| 393 | struct ieee802154_addr source; |
| 394 | struct ieee802154_addr dest; |
| 395 | }; |
| 396 | |
| 397 | static inline struct ieee802154_mac_cb *mac_cb(struct sk_buff *skb) |
| 398 | { |
| 399 | return (struct ieee802154_mac_cb *)skb->cb; |
| 400 | } |
| 401 | |
| 402 | static inline struct ieee802154_mac_cb *mac_cb_init(struct sk_buff *skb) |
| 403 | { |
| 404 | BUILD_BUG_ON(sizeof(struct ieee802154_mac_cb) > sizeof(skb->cb)); |
| 405 | |
| 406 | memset(skb->cb, 0, sizeof(struct ieee802154_mac_cb)); |
| 407 | return mac_cb(skb); |
| 408 | } |
| 409 | |
| 410 | enum { |
| 411 | IEEE802154_LLSEC_DEVKEY_IGNORE, |
| 412 | IEEE802154_LLSEC_DEVKEY_RESTRICT, |
| 413 | IEEE802154_LLSEC_DEVKEY_RECORD, |
| 414 | |
| 415 | __IEEE802154_LLSEC_DEVKEY_MAX, |
| 416 | }; |
| 417 | |
| 418 | #define IEEE802154_MAC_SCAN_ED 0 |
| 419 | #define IEEE802154_MAC_SCAN_ACTIVE 1 |
| 420 | #define IEEE802154_MAC_SCAN_PASSIVE 2 |
| 421 | #define IEEE802154_MAC_SCAN_ORPHAN 3 |
| 422 | |
| 423 | struct ieee802154_mac_params { |
| 424 | s8 transmit_power; |
| 425 | u8 min_be; |
| 426 | u8 max_be; |
| 427 | u8 csma_retries; |
| 428 | s8 frame_retries; |
| 429 | |
| 430 | bool lbt; |
| 431 | struct wpan_phy_cca cca; |
| 432 | s32 cca_ed_level; |
| 433 | }; |
| 434 | |
| 435 | struct wpan_phy; |
| 436 | |
| 437 | enum { |
| 438 | IEEE802154_LLSEC_PARAM_ENABLED = BIT(0), |
| 439 | IEEE802154_LLSEC_PARAM_FRAME_COUNTER = BIT(1), |
| 440 | IEEE802154_LLSEC_PARAM_OUT_LEVEL = BIT(2), |
| 441 | IEEE802154_LLSEC_PARAM_OUT_KEY = BIT(3), |
| 442 | IEEE802154_LLSEC_PARAM_KEY_SOURCE = BIT(4), |
| 443 | IEEE802154_LLSEC_PARAM_PAN_ID = BIT(5), |
| 444 | IEEE802154_LLSEC_PARAM_HWADDR = BIT(6), |
| 445 | IEEE802154_LLSEC_PARAM_COORD_HWADDR = BIT(7), |
| 446 | IEEE802154_LLSEC_PARAM_COORD_SHORTADDR = BIT(8), |
| 447 | }; |
| 448 | |
| 449 | struct ieee802154_llsec_ops { |
| 450 | int (*get_params)(struct net_device *dev, |
| 451 | struct ieee802154_llsec_params *params); |
| 452 | int (*set_params)(struct net_device *dev, |
| 453 | const struct ieee802154_llsec_params *params, |
| 454 | int changed); |
| 455 | |
| 456 | int (*add_key)(struct net_device *dev, |
| 457 | const struct ieee802154_llsec_key_id *id, |
| 458 | const struct ieee802154_llsec_key *key); |
| 459 | int (*del_key)(struct net_device *dev, |
| 460 | const struct ieee802154_llsec_key_id *id); |
| 461 | |
| 462 | int (*add_dev)(struct net_device *dev, |
| 463 | const struct ieee802154_llsec_device *llsec_dev); |
| 464 | int (*del_dev)(struct net_device *dev, __le64 dev_addr); |
| 465 | |
| 466 | int (*add_devkey)(struct net_device *dev, |
| 467 | __le64 device_addr, |
| 468 | const struct ieee802154_llsec_device_key *key); |
| 469 | int (*del_devkey)(struct net_device *dev, |
| 470 | __le64 device_addr, |
| 471 | const struct ieee802154_llsec_device_key *key); |
| 472 | |
| 473 | int (*add_seclevel)(struct net_device *dev, |
| 474 | const struct ieee802154_llsec_seclevel *sl); |
| 475 | int (*del_seclevel)(struct net_device *dev, |
| 476 | const struct ieee802154_llsec_seclevel *sl); |
| 477 | |
| 478 | void (*lock_table)(struct net_device *dev); |
| 479 | void (*get_table)(struct net_device *dev, |
| 480 | struct ieee802154_llsec_table **t); |
| 481 | void (*unlock_table)(struct net_device *dev); |
| 482 | }; |
| 483 | /* |
| 484 | * This should be located at net_device->ml_priv |
| 485 | * |
| 486 | * get_phy should increment the reference counting on returned phy. |
| 487 | * Use wpan_wpy_put to put that reference. |
| 488 | */ |
| 489 | struct ieee802154_mlme_ops { |
| 490 | /* The following fields are optional (can be NULL). */ |
| 491 | |
| 492 | int (*assoc_req)(struct net_device *dev, |
| 493 | struct ieee802154_addr *addr, |
| 494 | u8 channel, u8 page, u8 cap); |
| 495 | int (*assoc_resp)(struct net_device *dev, |
| 496 | struct ieee802154_addr *addr, |
| 497 | __le16 short_addr, u8 status); |
| 498 | int (*disassoc_req)(struct net_device *dev, |
| 499 | struct ieee802154_addr *addr, |
| 500 | u8 reason); |
| 501 | int (*start_req)(struct net_device *dev, |
| 502 | struct ieee802154_addr *addr, |
| 503 | u8 channel, u8 page, u8 bcn_ord, u8 sf_ord, |
| 504 | u8 pan_coord, u8 blx, u8 coord_realign); |
| 505 | int (*scan_req)(struct net_device *dev, |
| 506 | u8 type, u32 channels, u8 page, u8 duration); |
| 507 | |
| 508 | int (*set_mac_params)(struct net_device *dev, |
| 509 | const struct ieee802154_mac_params *params); |
| 510 | void (*get_mac_params)(struct net_device *dev, |
| 511 | struct ieee802154_mac_params *params); |
| 512 | |
| 513 | const struct ieee802154_llsec_ops *llsec; |
| 514 | }; |
| 515 | |
| 516 | static inline struct ieee802154_mlme_ops * |
| 517 | ieee802154_mlme_ops(const struct net_device *dev) |
| 518 | { |
| 519 | return dev->ml_priv; |
| 520 | } |
| 521 | |
| 522 | #endif |
| 523 | |