1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. NET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the Ethernet handlers. 8 * 9 * Version: @(#)eth.h 1.0.4 05/13/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * 14 * Relocated to include/linux where it belongs by Alan Cox 15 * <gw4pts@gw4pts.ampr.org> 16 */ 17 #ifndef _LINUX_ETHERDEVICE_H 18 #define _LINUX_ETHERDEVICE_H 19 20 #include <linux/if_ether.h> 21 #include <linux/netdevice.h> 22 #include <linux/random.h> 23 #include <linux/crc32.h> 24 #include <asm/unaligned.h> 25 #include <asm/bitsperlong.h> 26 27 #ifdef __KERNEL__ 28 struct device; 29 int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr); 30 unsigned char *arch_get_platform_mac_address(void); 31 int nvmem_get_mac_address(struct device *dev, void *addrbuf); 32 u32 eth_get_headlen(const struct net_device *dev, const void *data, u32 len); 33 __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev); 34 extern const struct header_ops eth_header_ops; 35 36 int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, 37 const void *daddr, const void *saddr, unsigned len); 38 int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr); 39 int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, 40 __be16 type); 41 void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev, 42 const unsigned char *haddr); 43 __be16 eth_header_parse_protocol(const struct sk_buff *skb); 44 int eth_prepare_mac_addr_change(struct net_device *dev, void *p); 45 void eth_commit_mac_addr_change(struct net_device *dev, void *p); 46 int eth_mac_addr(struct net_device *dev, void *p); 47 int eth_validate_addr(struct net_device *dev); 48 49 struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs, 50 unsigned int rxqs); 51 #define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1) 52 #define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count) 53 54 struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv, 55 unsigned int txqs, 56 unsigned int rxqs); 57 #define devm_alloc_etherdev(dev, sizeof_priv) devm_alloc_etherdev_mqs(dev, sizeof_priv, 1, 1) 58 59 struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb); 60 int eth_gro_complete(struct sk_buff *skb, int nhoff); 61 62 /* Reserved Ethernet Addresses per IEEE 802.1Q */ 63 static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) = 64 { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }; 65 #define eth_stp_addr eth_reserved_addr_base 66 67 /** 68 * is_link_local_ether_addr - Determine if given Ethernet address is link-local 69 * @addr: Pointer to a six-byte array containing the Ethernet address 70 * 71 * Return true if address is link local reserved addr (01:80:c2:00:00:0X) per 72 * IEEE 802.1Q 8.6.3 Frame filtering. 73 * 74 * Please note: addr must be aligned to u16. 75 */ 76 static inline bool is_link_local_ether_addr(const u8 *addr) 77 { 78 __be16 *a = (__be16 *)addr; 79 static const __be16 *b = (const __be16 *)eth_reserved_addr_base; 80 static const __be16 m = cpu_to_be16(0xfff0); 81 82 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 83 return (((*(const u32 *)addr) ^ (*(const u32 *)b)) | 84 (__force int)((a[2] ^ b[2]) & m)) == 0; 85 #else 86 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0; 87 #endif 88 } 89 90 /** 91 * is_zero_ether_addr - Determine if give Ethernet address is all zeros. 92 * @addr: Pointer to a six-byte array containing the Ethernet address 93 * 94 * Return true if the address is all zeroes. 95 * 96 * Please note: addr must be aligned to u16. 97 */ 98 static inline bool is_zero_ether_addr(const u8 *addr) 99 { 100 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 101 return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0; 102 #else 103 return (*(const u16 *)(addr + 0) | 104 *(const u16 *)(addr + 2) | 105 *(const u16 *)(addr + 4)) == 0; 106 #endif 107 } 108 109 /** 110 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast. 111 * @addr: Pointer to a six-byte array containing the Ethernet address 112 * 113 * Return true if the address is a multicast address. 114 * By definition the broadcast address is also a multicast address. 115 */ 116 static inline bool is_multicast_ether_addr(const u8 *addr) 117 { 118 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 119 u32 a = *(const u32 *)addr; 120 #else 121 u16 a = *(const u16 *)addr; 122 #endif 123 #ifdef __BIG_ENDIAN 124 return 0x01 & (a >> ((sizeof(a) * 8) - 8)); 125 #else 126 return 0x01 & a; 127 #endif 128 } 129 130 static inline bool is_multicast_ether_addr_64bits(const u8 addr[6+2]) 131 { 132 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 133 #ifdef __BIG_ENDIAN 134 return 0x01 & ((*(const u64 *)addr) >> 56); 135 #else 136 return 0x01 & (*(const u64 *)addr); 137 #endif 138 #else 139 return is_multicast_ether_addr(addr); 140 #endif 141 } 142 143 /** 144 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802). 145 * @addr: Pointer to a six-byte array containing the Ethernet address 146 * 147 * Return true if the address is a local address. 148 */ 149 static inline bool is_local_ether_addr(const u8 *addr) 150 { 151 return 0x02 & addr[0]; 152 } 153 154 /** 155 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast 156 * @addr: Pointer to a six-byte array containing the Ethernet address 157 * 158 * Return true if the address is the broadcast address. 159 * 160 * Please note: addr must be aligned to u16. 161 */ 162 static inline bool is_broadcast_ether_addr(const u8 *addr) 163 { 164 return (*(const u16 *)(addr + 0) & 165 *(const u16 *)(addr + 2) & 166 *(const u16 *)(addr + 4)) == 0xffff; 167 } 168 169 /** 170 * is_unicast_ether_addr - Determine if the Ethernet address is unicast 171 * @addr: Pointer to a six-byte array containing the Ethernet address 172 * 173 * Return true if the address is a unicast address. 174 */ 175 static inline bool is_unicast_ether_addr(const u8 *addr) 176 { 177 return !is_multicast_ether_addr(addr); 178 } 179 180 /** 181 * is_valid_ether_addr - Determine if the given Ethernet address is valid 182 * @addr: Pointer to a six-byte array containing the Ethernet address 183 * 184 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not 185 * a multicast address, and is not FF:FF:FF:FF:FF:FF. 186 * 187 * Return true if the address is valid. 188 * 189 * Please note: addr must be aligned to u16. 190 */ 191 static inline bool is_valid_ether_addr(const u8 *addr) 192 { 193 /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to 194 * explicitly check for it here. */ 195 return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr); 196 } 197 198 /** 199 * eth_proto_is_802_3 - Determine if a given Ethertype/length is a protocol 200 * @proto: Ethertype/length value to be tested 201 * 202 * Check that the value from the Ethertype/length field is a valid Ethertype. 203 * 204 * Return true if the valid is an 802.3 supported Ethertype. 205 */ 206 static inline bool eth_proto_is_802_3(__be16 proto) 207 { 208 #ifndef __BIG_ENDIAN 209 /* if CPU is little endian mask off bits representing LSB */ 210 proto &= htons(0xFF00); 211 #endif 212 /* cast both to u16 and compare since LSB can be ignored */ 213 return (__force u16)proto >= (__force u16)htons(ETH_P_802_3_MIN); 214 } 215 216 /** 217 * eth_random_addr - Generate software assigned random Ethernet address 218 * @addr: Pointer to a six-byte array containing the Ethernet address 219 * 220 * Generate a random Ethernet address (MAC) that is not multicast 221 * and has the local assigned bit set. 222 */ 223 static inline void eth_random_addr(u8 *addr) 224 { 225 get_random_bytes(addr, ETH_ALEN); 226 addr[0] &= 0xfe; /* clear multicast bit */ 227 addr[0] |= 0x02; /* set local assignment bit (IEEE802) */ 228 } 229 230 #define random_ether_addr(addr) eth_random_addr(addr) 231 232 /** 233 * eth_broadcast_addr - Assign broadcast address 234 * @addr: Pointer to a six-byte array containing the Ethernet address 235 * 236 * Assign the broadcast address to the given address array. 237 */ 238 static inline void eth_broadcast_addr(u8 *addr) 239 { 240 memset(addr, 0xff, ETH_ALEN); 241 } 242 243 /** 244 * eth_zero_addr - Assign zero address 245 * @addr: Pointer to a six-byte array containing the Ethernet address 246 * 247 * Assign the zero address to the given address array. 248 */ 249 static inline void eth_zero_addr(u8 *addr) 250 { 251 memset(addr, 0x00, ETH_ALEN); 252 } 253 254 /** 255 * eth_hw_addr_random - Generate software assigned random Ethernet and 256 * set device flag 257 * @dev: pointer to net_device structure 258 * 259 * Generate a random Ethernet address (MAC) to be used by a net device 260 * and set addr_assign_type so the state can be read by sysfs and be 261 * used by userspace. 262 */ 263 static inline void eth_hw_addr_random(struct net_device *dev) 264 { 265 dev->addr_assign_type = NET_ADDR_RANDOM; 266 eth_random_addr(dev->dev_addr); 267 } 268 269 /** 270 * eth_hw_addr_crc - Calculate CRC from netdev_hw_addr 271 * @ha: pointer to hardware address 272 * 273 * Calculate CRC from a hardware address as basis for filter hashes. 274 */ 275 static inline u32 eth_hw_addr_crc(struct netdev_hw_addr *ha) 276 { 277 return ether_crc(ETH_ALEN, ha->addr); 278 } 279 280 /** 281 * ether_addr_copy - Copy an Ethernet address 282 * @dst: Pointer to a six-byte array Ethernet address destination 283 * @src: Pointer to a six-byte array Ethernet address source 284 * 285 * Please note: dst & src must both be aligned to u16. 286 */ 287 static inline void ether_addr_copy(u8 *dst, const u8 *src) 288 { 289 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 290 *(u32 *)dst = *(const u32 *)src; 291 *(u16 *)(dst + 4) = *(const u16 *)(src + 4); 292 #else 293 u16 *a = (u16 *)dst; 294 const u16 *b = (const u16 *)src; 295 296 a[0] = b[0]; 297 a[1] = b[1]; 298 a[2] = b[2]; 299 #endif 300 } 301 302 /** 303 * eth_hw_addr_set - Assign Ethernet address to a net_device 304 * @dev: pointer to net_device structure 305 * @addr: address to assign 306 * 307 * Assign given address to the net_device, addr_assign_type is not changed. 308 */ 309 static inline void eth_hw_addr_set(struct net_device *dev, const u8 *addr) 310 { 311 ether_addr_copy(dev->dev_addr, addr); 312 } 313 314 /** 315 * eth_hw_addr_inherit - Copy dev_addr from another net_device 316 * @dst: pointer to net_device to copy dev_addr to 317 * @src: pointer to net_device to copy dev_addr from 318 * 319 * Copy the Ethernet address from one net_device to another along with 320 * the address attributes (addr_assign_type). 321 */ 322 static inline void eth_hw_addr_inherit(struct net_device *dst, 323 struct net_device *src) 324 { 325 dst->addr_assign_type = src->addr_assign_type; 326 ether_addr_copy(dst->dev_addr, src->dev_addr); 327 } 328 329 /** 330 * ether_addr_equal - Compare two Ethernet addresses 331 * @addr1: Pointer to a six-byte array containing the Ethernet address 332 * @addr2: Pointer other six-byte array containing the Ethernet address 333 * 334 * Compare two Ethernet addresses, returns true if equal 335 * 336 * Please note: addr1 & addr2 must both be aligned to u16. 337 */ 338 static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2) 339 { 340 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 341 u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) | 342 ((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4))); 343 344 return fold == 0; 345 #else 346 const u16 *a = (const u16 *)addr1; 347 const u16 *b = (const u16 *)addr2; 348 349 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0; 350 #endif 351 } 352 353 /** 354 * ether_addr_equal_64bits - Compare two Ethernet addresses 355 * @addr1: Pointer to an array of 8 bytes 356 * @addr2: Pointer to an other array of 8 bytes 357 * 358 * Compare two Ethernet addresses, returns true if equal, false otherwise. 359 * 360 * The function doesn't need any conditional branches and possibly uses 361 * word memory accesses on CPU allowing cheap unaligned memory reads. 362 * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 } 363 * 364 * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits. 365 */ 366 367 static inline bool ether_addr_equal_64bits(const u8 addr1[6+2], 368 const u8 addr2[6+2]) 369 { 370 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 371 u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2); 372 373 #ifdef __BIG_ENDIAN 374 return (fold >> 16) == 0; 375 #else 376 return (fold << 16) == 0; 377 #endif 378 #else 379 return ether_addr_equal(addr1, addr2); 380 #endif 381 } 382 383 /** 384 * ether_addr_equal_unaligned - Compare two not u16 aligned Ethernet addresses 385 * @addr1: Pointer to a six-byte array containing the Ethernet address 386 * @addr2: Pointer other six-byte array containing the Ethernet address 387 * 388 * Compare two Ethernet addresses, returns true if equal 389 * 390 * Please note: Use only when any Ethernet address may not be u16 aligned. 391 */ 392 static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2) 393 { 394 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 395 return ether_addr_equal(addr1, addr2); 396 #else 397 return memcmp(addr1, addr2, ETH_ALEN) == 0; 398 #endif 399 } 400 401 /** 402 * ether_addr_equal_masked - Compare two Ethernet addresses with a mask 403 * @addr1: Pointer to a six-byte array containing the 1st Ethernet address 404 * @addr2: Pointer to a six-byte array containing the 2nd Ethernet address 405 * @mask: Pointer to a six-byte array containing the Ethernet address bitmask 406 * 407 * Compare two Ethernet addresses with a mask, returns true if for every bit 408 * set in the bitmask the equivalent bits in the ethernet addresses are equal. 409 * Using a mask with all bits set is a slower ether_addr_equal. 410 */ 411 static inline bool ether_addr_equal_masked(const u8 *addr1, const u8 *addr2, 412 const u8 *mask) 413 { 414 int i; 415 416 for (i = 0; i < ETH_ALEN; i++) { 417 if ((addr1[i] ^ addr2[i]) & mask[i]) 418 return false; 419 } 420 421 return true; 422 } 423 424 /** 425 * ether_addr_to_u64 - Convert an Ethernet address into a u64 value. 426 * @addr: Pointer to a six-byte array containing the Ethernet address 427 * 428 * Return a u64 value of the address 429 */ 430 static inline u64 ether_addr_to_u64(const u8 *addr) 431 { 432 u64 u = 0; 433 int i; 434 435 for (i = 0; i < ETH_ALEN; i++) 436 u = u << 8 | addr[i]; 437 438 return u; 439 } 440 441 /** 442 * u64_to_ether_addr - Convert a u64 to an Ethernet address. 443 * @u: u64 to convert to an Ethernet MAC address 444 * @addr: Pointer to a six-byte array to contain the Ethernet address 445 */ 446 static inline void u64_to_ether_addr(u64 u, u8 *addr) 447 { 448 int i; 449 450 for (i = ETH_ALEN - 1; i >= 0; i--) { 451 addr[i] = u & 0xff; 452 u = u >> 8; 453 } 454 } 455 456 /** 457 * eth_addr_dec - Decrement the given MAC address 458 * 459 * @addr: Pointer to a six-byte array containing Ethernet address to decrement 460 */ 461 static inline void eth_addr_dec(u8 *addr) 462 { 463 u64 u = ether_addr_to_u64(addr); 464 465 u--; 466 u64_to_ether_addr(u, addr); 467 } 468 469 /** 470 * eth_addr_inc() - Increment the given MAC address. 471 * @addr: Pointer to a six-byte array containing Ethernet address to increment. 472 */ 473 static inline void eth_addr_inc(u8 *addr) 474 { 475 u64 u = ether_addr_to_u64(addr); 476 477 u++; 478 u64_to_ether_addr(u, addr); 479 } 480 481 /** 482 * is_etherdev_addr - Tell if given Ethernet address belongs to the device. 483 * @dev: Pointer to a device structure 484 * @addr: Pointer to a six-byte array containing the Ethernet address 485 * 486 * Compare passed address with all addresses of the device. Return true if the 487 * address if one of the device addresses. 488 * 489 * Note that this function calls ether_addr_equal_64bits() so take care of 490 * the right padding. 491 */ 492 static inline bool is_etherdev_addr(const struct net_device *dev, 493 const u8 addr[6 + 2]) 494 { 495 struct netdev_hw_addr *ha; 496 bool res = false; 497 498 rcu_read_lock(); 499 for_each_dev_addr(dev, ha) { 500 res = ether_addr_equal_64bits(addr, ha->addr); 501 if (res) 502 break; 503 } 504 rcu_read_unlock(); 505 return res; 506 } 507 #endif /* __KERNEL__ */ 508 509 /** 510 * compare_ether_header - Compare two Ethernet headers 511 * @a: Pointer to Ethernet header 512 * @b: Pointer to Ethernet header 513 * 514 * Compare two Ethernet headers, returns 0 if equal. 515 * This assumes that the network header (i.e., IP header) is 4-byte 516 * aligned OR the platform can handle unaligned access. This is the 517 * case for all packets coming into netif_receive_skb or similar 518 * entry points. 519 */ 520 521 static inline unsigned long compare_ether_header(const void *a, const void *b) 522 { 523 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 524 unsigned long fold; 525 526 /* 527 * We want to compare 14 bytes: 528 * [a0 ... a13] ^ [b0 ... b13] 529 * Use two long XOR, ORed together, with an overlap of two bytes. 530 * [a0 a1 a2 a3 a4 a5 a6 a7 ] ^ [b0 b1 b2 b3 b4 b5 b6 b7 ] | 531 * [a6 a7 a8 a9 a10 a11 a12 a13] ^ [b6 b7 b8 b9 b10 b11 b12 b13] 532 * This means the [a6 a7] ^ [b6 b7] part is done two times. 533 */ 534 fold = *(unsigned long *)a ^ *(unsigned long *)b; 535 fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6); 536 return fold; 537 #else 538 u32 *a32 = (u32 *)((u8 *)a + 2); 539 u32 *b32 = (u32 *)((u8 *)b + 2); 540 541 return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) | 542 (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]); 543 #endif 544 } 545 546 /** 547 * eth_skb_pad - Pad buffer to mininum number of octets for Ethernet frame 548 * @skb: Buffer to pad 549 * 550 * An Ethernet frame should have a minimum size of 60 bytes. This function 551 * takes short frames and pads them with zeros up to the 60 byte limit. 552 */ 553 static inline int eth_skb_pad(struct sk_buff *skb) 554 { 555 return skb_put_padto(skb, ETH_ZLEN); 556 } 557 558 #endif /* _LINUX_ETHERDEVICE_H */ 559