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