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__ 28struct device; 29struct fwnode_handle; 30 31int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr); 32int platform_get_ethdev_address(struct device *dev, struct net_device *netdev); 33unsigned char *arch_get_platform_mac_address(void); 34int nvmem_get_mac_address(struct device *dev, void *addrbuf); 35int device_get_mac_address(struct device *dev, char *addr); 36int device_get_ethdev_address(struct device *dev, struct net_device *netdev); 37int fwnode_get_mac_address(struct fwnode_handle *fwnode, char *addr); 38 39u32 eth_get_headlen(const struct net_device *dev, const void *data, u32 len); 40__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev); 41extern const struct header_ops eth_header_ops; 42 43int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, 44 const void *daddr, const void *saddr, unsigned len); 45int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr); 46int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, 47 __be16 type); 48void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev, 49 const unsigned char *haddr); 50__be16 eth_header_parse_protocol(const struct sk_buff *skb); 51int eth_prepare_mac_addr_change(struct net_device *dev, void *p); 52void eth_commit_mac_addr_change(struct net_device *dev, void *p); 53int eth_mac_addr(struct net_device *dev, void *p); 54int eth_validate_addr(struct net_device *dev); 55 56struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs, 57 unsigned int rxqs); 58#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1) 59#define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count) 60 61struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv, 62 unsigned int txqs, 63 unsigned int rxqs); 64#define devm_alloc_etherdev(dev, sizeof_priv) devm_alloc_etherdev_mqs(dev, sizeof_priv, 1, 1) 65 66struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb); 67int eth_gro_complete(struct sk_buff *skb, int nhoff); 68 69/* Reserved Ethernet Addresses per IEEE 802.1Q */ 70static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) = 71{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }; 72#define eth_stp_addr eth_reserved_addr_base 73 74/** 75 * is_link_local_ether_addr - Determine if given Ethernet address is link-local 76 * @addr: Pointer to a six-byte array containing the Ethernet address 77 * 78 * Return true if address is link local reserved addr (01:80:c2:00:00:0X) per 79 * IEEE 802.1Q 8.6.3 Frame filtering. 80 * 81 * Please note: addr must be aligned to u16. 82 */ 83static inline bool is_link_local_ether_addr(const u8 *addr) 84{ 85 __be16 *a = (__be16 *)addr; 86 static const __be16 *b = (const __be16 *)eth_reserved_addr_base; 87 static const __be16 m = cpu_to_be16(0xfff0); 88 89#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 90 return (((*(const u32 *)addr) ^ (*(const u32 *)b)) | 91 (__force int)((a[2] ^ b[2]) & m)) == 0; 92#else 93 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0; 94#endif 95} 96 97/** 98 * is_zero_ether_addr - Determine if give Ethernet address is all zeros. 99 * @addr: Pointer to a six-byte array containing the Ethernet address 100 * 101 * Return true if the address is all zeroes. 102 * 103 * Please note: addr must be aligned to u16. 104 */ 105static inline bool is_zero_ether_addr(const u8 *addr) 106{ 107#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 108 return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0; 109#else 110 return (*(const u16 *)(addr + 0) | 111 *(const u16 *)(addr + 2) | 112 *(const u16 *)(addr + 4)) == 0; 113#endif 114} 115 116/** 117 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast. 118 * @addr: Pointer to a six-byte array containing the Ethernet address 119 * 120 * Return true if the address is a multicast address. 121 * By definition the broadcast address is also a multicast address. 122 */ 123static inline bool is_multicast_ether_addr(const u8 *addr) 124{ 125#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 126 u32 a = *(const u32 *)addr; 127#else 128 u16 a = *(const u16 *)addr; 129#endif 130#ifdef __BIG_ENDIAN 131 return 0x01 & (a >> ((sizeof(a) * 8) - 8)); 132#else 133 return 0x01 & a; 134#endif 135} 136 137static inline bool is_multicast_ether_addr_64bits(const u8 *addr) 138{ 139#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 140#ifdef __BIG_ENDIAN 141 return 0x01 & ((*(const u64 *)addr) >> 56); 142#else 143 return 0x01 & (*(const u64 *)addr); 144#endif 145#else 146 return is_multicast_ether_addr(addr); 147#endif 148} 149 150/** 151 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802). 152 * @addr: Pointer to a six-byte array containing the Ethernet address 153 * 154 * Return true if the address is a local address. 155 */ 156static inline bool is_local_ether_addr(const u8 *addr) 157{ 158 return 0x02 & addr[0]; 159} 160 161/** 162 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast 163 * @addr: Pointer to a six-byte array containing the Ethernet address 164 * 165 * Return true if the address is the broadcast address. 166 * 167 * Please note: addr must be aligned to u16. 168 */ 169static inline bool is_broadcast_ether_addr(const u8 *addr) 170{ 171 return (*(const u16 *)(addr + 0) & 172 *(const u16 *)(addr + 2) & 173 *(const u16 *)(addr + 4)) == 0xffff; 174} 175 176/** 177 * is_unicast_ether_addr - Determine if the Ethernet address is unicast 178 * @addr: Pointer to a six-byte array containing the Ethernet address 179 * 180 * Return true if the address is a unicast address. 181 */ 182static inline bool is_unicast_ether_addr(const u8 *addr) 183{ 184 return !is_multicast_ether_addr(addr); 185} 186 187/** 188 * is_valid_ether_addr - Determine if the given Ethernet address is valid 189 * @addr: Pointer to a six-byte array containing the Ethernet address 190 * 191 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not 192 * a multicast address, and is not FF:FF:FF:FF:FF:FF. 193 * 194 * Return true if the address is valid. 195 * 196 * Please note: addr must be aligned to u16. 197 */ 198static inline bool is_valid_ether_addr(const u8 *addr) 199{ 200 /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to 201 * explicitly check for it here. */ 202 return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr); 203} 204 205/** 206 * eth_proto_is_802_3 - Determine if a given Ethertype/length is a protocol 207 * @proto: Ethertype/length value to be tested 208 * 209 * Check that the value from the Ethertype/length field is a valid Ethertype. 210 * 211 * Return true if the valid is an 802.3 supported Ethertype. 212 */ 213static inline bool eth_proto_is_802_3(__be16 proto) 214{ 215#ifndef __BIG_ENDIAN 216 /* if CPU is little endian mask off bits representing LSB */ 217 proto &= htons(0xFF00); 218#endif 219 /* cast both to u16 and compare since LSB can be ignored */ 220 return (__force u16)proto >= (__force u16)htons(ETH_P_802_3_MIN); 221} 222 223/** 224 * eth_random_addr - Generate software assigned random Ethernet address 225 * @addr: Pointer to a six-byte array containing the Ethernet address 226 * 227 * Generate a random Ethernet address (MAC) that is not multicast 228 * and has the local assigned bit set. 229 */ 230static inline void eth_random_addr(u8 *addr) 231{ 232 get_random_bytes(addr, ETH_ALEN); 233 addr[0] &= 0xfe; /* clear multicast bit */ 234 addr[0] |= 0x02; /* set local assignment bit (IEEE802) */ 235} 236 237/** 238 * eth_broadcast_addr - Assign broadcast address 239 * @addr: Pointer to a six-byte array containing the Ethernet address 240 * 241 * Assign the broadcast address to the given address array. 242 */ 243static inline void eth_broadcast_addr(u8 *addr) 244{ 245 memset(addr, 0xff, ETH_ALEN); 246} 247 248/** 249 * eth_zero_addr - Assign zero address 250 * @addr: Pointer to a six-byte array containing the Ethernet address 251 * 252 * Assign the zero address to the given address array. 253 */ 254static inline void eth_zero_addr(u8 *addr) 255{ 256 memset(addr, 0x00, ETH_ALEN); 257} 258 259/** 260 * eth_hw_addr_random - Generate software assigned random Ethernet and 261 * set device flag 262 * @dev: pointer to net_device structure 263 * 264 * Generate a random Ethernet address (MAC) to be used by a net device 265 * and set addr_assign_type so the state can be read by sysfs and be 266 * used by userspace. 267 */ 268static inline void eth_hw_addr_random(struct net_device *dev) 269{ 270 u8 addr[ETH_ALEN]; 271 272 eth_random_addr(addr); 273 __dev_addr_set(dev, addr, ETH_ALEN); 274 dev->addr_assign_type = NET_ADDR_RANDOM; 275} 276 277/** 278 * eth_hw_addr_crc - Calculate CRC from netdev_hw_addr 279 * @ha: pointer to hardware address 280 * 281 * Calculate CRC from a hardware address as basis for filter hashes. 282 */ 283static inline u32 eth_hw_addr_crc(struct netdev_hw_addr *ha) 284{ 285 return ether_crc(ETH_ALEN, ha->addr); 286} 287 288/** 289 * ether_addr_copy - Copy an Ethernet address 290 * @dst: Pointer to a six-byte array Ethernet address destination 291 * @src: Pointer to a six-byte array Ethernet address source 292 * 293 * Please note: dst & src must both be aligned to u16. 294 */ 295static inline void ether_addr_copy(u8 *dst, const u8 *src) 296{ 297#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 298 *(u32 *)dst = *(const u32 *)src; 299 *(u16 *)(dst + 4) = *(const u16 *)(src + 4); 300#else 301 u16 *a = (u16 *)dst; 302 const u16 *b = (const u16 *)src; 303 304 a[0] = b[0]; 305 a[1] = b[1]; 306 a[2] = b[2]; 307#endif 308} 309 310/** 311 * eth_hw_addr_set - Assign Ethernet address to a net_device 312 * @dev: pointer to net_device structure 313 * @addr: address to assign 314 * 315 * Assign given address to the net_device, addr_assign_type is not changed. 316 */ 317static inline void eth_hw_addr_set(struct net_device *dev, const u8 *addr) 318{ 319 __dev_addr_set(dev, addr, ETH_ALEN); 320} 321 322/** 323 * eth_hw_addr_inherit - Copy dev_addr from another net_device 324 * @dst: pointer to net_device to copy dev_addr to 325 * @src: pointer to net_device to copy dev_addr from 326 * 327 * Copy the Ethernet address from one net_device to another along with 328 * the address attributes (addr_assign_type). 329 */ 330static inline void eth_hw_addr_inherit(struct net_device *dst, 331 struct net_device *src) 332{ 333 dst->addr_assign_type = src->addr_assign_type; 334 eth_hw_addr_set(dst, src->dev_addr); 335} 336 337/** 338 * ether_addr_equal - Compare two Ethernet addresses 339 * @addr1: Pointer to a six-byte array containing the Ethernet address 340 * @addr2: Pointer other six-byte array containing the Ethernet address 341 * 342 * Compare two Ethernet addresses, returns true if equal 343 * 344 * Please note: addr1 & addr2 must both be aligned to u16. 345 */ 346static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2) 347{ 348#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 349 u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) | 350 ((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4))); 351 352 return fold == 0; 353#else 354 const u16 *a = (const u16 *)addr1; 355 const u16 *b = (const u16 *)addr2; 356 357 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0; 358#endif 359} 360 361/** 362 * ether_addr_equal_64bits - Compare two Ethernet addresses 363 * @addr1: Pointer to an array of 8 bytes 364 * @addr2: Pointer to an other array of 8 bytes 365 * 366 * Compare two Ethernet addresses, returns true if equal, false otherwise. 367 * 368 * The function doesn't need any conditional branches and possibly uses 369 * word memory accesses on CPU allowing cheap unaligned memory reads. 370 * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 } 371 * 372 * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits. 373 */ 374 375static inline bool ether_addr_equal_64bits(const u8 *addr1, const u8 *addr2) 376{ 377#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 378 u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2); 379 380#ifdef __BIG_ENDIAN 381 return (fold >> 16) == 0; 382#else 383 return (fold << 16) == 0; 384#endif 385#else 386 return ether_addr_equal(addr1, addr2); 387#endif 388} 389 390/** 391 * ether_addr_equal_unaligned - Compare two not u16 aligned Ethernet addresses 392 * @addr1: Pointer to a six-byte array containing the Ethernet address 393 * @addr2: Pointer other six-byte array containing the Ethernet address 394 * 395 * Compare two Ethernet addresses, returns true if equal 396 * 397 * Please note: Use only when any Ethernet address may not be u16 aligned. 398 */ 399static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2) 400{ 401#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 402 return ether_addr_equal(addr1, addr2); 403#else 404 return memcmp(addr1, addr2, ETH_ALEN) == 0; 405#endif 406} 407 408/** 409 * ether_addr_equal_masked - Compare two Ethernet addresses with a mask 410 * @addr1: Pointer to a six-byte array containing the 1st Ethernet address 411 * @addr2: Pointer to a six-byte array containing the 2nd Ethernet address 412 * @mask: Pointer to a six-byte array containing the Ethernet address bitmask 413 * 414 * Compare two Ethernet addresses with a mask, returns true if for every bit 415 * set in the bitmask the equivalent bits in the ethernet addresses are equal. 416 * Using a mask with all bits set is a slower ether_addr_equal. 417 */ 418static inline bool ether_addr_equal_masked(const u8 *addr1, const u8 *addr2, 419 const u8 *mask) 420{ 421 int i; 422 423 for (i = 0; i < ETH_ALEN; i++) { 424 if ((addr1[i] ^ addr2[i]) & mask[i]) 425 return false; 426 } 427 428 return true; 429} 430 431static inline bool ether_addr_is_ipv4_mcast(const u8 *addr) 432{ 433 u8 base[ETH_ALEN] = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 }; 434 u8 mask[ETH_ALEN] = { 0xff, 0xff, 0xff, 0x80, 0x00, 0x00 }; 435 436 return ether_addr_equal_masked(addr, base, mask); 437} 438 439static inline bool ether_addr_is_ipv6_mcast(const u8 *addr) 440{ 441 u8 base[ETH_ALEN] = { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 }; 442 u8 mask[ETH_ALEN] = { 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 }; 443 444 return ether_addr_equal_masked(addr, base, mask); 445} 446 447static inline bool ether_addr_is_ip_mcast(const u8 *addr) 448{ 449 return ether_addr_is_ipv4_mcast(addr) || 450 ether_addr_is_ipv6_mcast(addr); 451} 452 453/** 454 * ether_addr_to_u64 - Convert an Ethernet address into a u64 value. 455 * @addr: Pointer to a six-byte array containing the Ethernet address 456 * 457 * Return a u64 value of the address 458 */ 459static inline u64 ether_addr_to_u64(const u8 *addr) 460{ 461 u64 u = 0; 462 int i; 463 464 for (i = 0; i < ETH_ALEN; i++) 465 u = u << 8 | addr[i]; 466 467 return u; 468} 469 470/** 471 * u64_to_ether_addr - Convert a u64 to an Ethernet address. 472 * @u: u64 to convert to an Ethernet MAC address 473 * @addr: Pointer to a six-byte array to contain the Ethernet address 474 */ 475static inline void u64_to_ether_addr(u64 u, u8 *addr) 476{ 477 int i; 478 479 for (i = ETH_ALEN - 1; i >= 0; i--) { 480 addr[i] = u & 0xff; 481 u = u >> 8; 482 } 483} 484 485/** 486 * eth_addr_dec - Decrement the given MAC address 487 * 488 * @addr: Pointer to a six-byte array containing Ethernet address to decrement 489 */ 490static inline void eth_addr_dec(u8 *addr) 491{ 492 u64 u = ether_addr_to_u64(addr); 493 494 u--; 495 u64_to_ether_addr(u, addr); 496} 497 498/** 499 * eth_addr_inc() - Increment the given MAC address. 500 * @addr: Pointer to a six-byte array containing Ethernet address to increment. 501 */ 502static inline void eth_addr_inc(u8 *addr) 503{ 504 u64 u = ether_addr_to_u64(addr); 505 506 u++; 507 u64_to_ether_addr(u, addr); 508} 509 510/** 511 * eth_addr_add() - Add (or subtract) an offset to/from the given MAC address. 512 * 513 * @offset: Offset to add. 514 * @addr: Pointer to a six-byte array containing Ethernet address to increment. 515 */ 516static inline void eth_addr_add(u8 *addr, long offset) 517{ 518 u64 u = ether_addr_to_u64(addr); 519 520 u += offset; 521 u64_to_ether_addr(u, addr); 522} 523 524/** 525 * is_etherdev_addr - Tell if given Ethernet address belongs to the device. 526 * @dev: Pointer to a device structure 527 * @addr: Pointer to a six-byte array containing the Ethernet address 528 * 529 * Compare passed address with all addresses of the device. Return true if the 530 * address if one of the device addresses. 531 * 532 * Note that this function calls ether_addr_equal_64bits() so take care of 533 * the right padding. 534 */ 535static inline bool is_etherdev_addr(const struct net_device *dev, 536 const u8 addr[6 + 2]) 537{ 538 struct netdev_hw_addr *ha; 539 bool res = false; 540 541 rcu_read_lock(); 542 for_each_dev_addr(dev, ha) { 543 res = ether_addr_equal_64bits(addr, ha->addr); 544 if (res) 545 break; 546 } 547 rcu_read_unlock(); 548 return res; 549} 550#endif /* __KERNEL__ */ 551 552/** 553 * compare_ether_header - Compare two Ethernet headers 554 * @a: Pointer to Ethernet header 555 * @b: Pointer to Ethernet header 556 * 557 * Compare two Ethernet headers, returns 0 if equal. 558 * This assumes that the network header (i.e., IP header) is 4-byte 559 * aligned OR the platform can handle unaligned access. This is the 560 * case for all packets coming into netif_receive_skb or similar 561 * entry points. 562 */ 563 564static inline unsigned long compare_ether_header(const void *a, const void *b) 565{ 566#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 567 unsigned long fold; 568 569 /* 570 * We want to compare 14 bytes: 571 * [a0 ... a13] ^ [b0 ... b13] 572 * Use two long XOR, ORed together, with an overlap of two bytes. 573 * [a0 a1 a2 a3 a4 a5 a6 a7 ] ^ [b0 b1 b2 b3 b4 b5 b6 b7 ] | 574 * [a6 a7 a8 a9 a10 a11 a12 a13] ^ [b6 b7 b8 b9 b10 b11 b12 b13] 575 * This means the [a6 a7] ^ [b6 b7] part is done two times. 576 */ 577 fold = *(unsigned long *)a ^ *(unsigned long *)b; 578 fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6); 579 return fold; 580#else 581 u32 *a32 = (u32 *)((u8 *)a + 2); 582 u32 *b32 = (u32 *)((u8 *)b + 2); 583 584 return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) | 585 (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]); 586#endif 587} 588 589/** 590 * eth_hw_addr_gen - Generate and assign Ethernet address to a port 591 * @dev: pointer to port's net_device structure 592 * @base_addr: base Ethernet address 593 * @id: offset to add to the base address 594 * 595 * Generate a MAC address using a base address and an offset and assign it 596 * to a net_device. Commonly used by switch drivers which need to compute 597 * addresses for all their ports. addr_assign_type is not changed. 598 */ 599static inline void eth_hw_addr_gen(struct net_device *dev, const u8 *base_addr, 600 unsigned int id) 601{ 602 u64 u = ether_addr_to_u64(base_addr); 603 u8 addr[ETH_ALEN]; 604 605 u += id; 606 u64_to_ether_addr(u, addr); 607 eth_hw_addr_set(dev, addr); 608} 609 610/** 611 * eth_skb_pad - Pad buffer to mininum number of octets for Ethernet frame 612 * @skb: Buffer to pad 613 * 614 * An Ethernet frame should have a minimum size of 60 bytes. This function 615 * takes short frames and pads them with zeros up to the 60 byte limit. 616 */ 617static inline int eth_skb_pad(struct sk_buff *skb) 618{ 619 return skb_put_padto(skb, ETH_ZLEN); 620} 621 622#endif /* _LINUX_ETHERDEVICE_H */ 623