compare_ether_header(9)

💅 compare_ether_header(9)

okay so bestie, welcome to the Kernel API Manual page for compare_ether_header(9) — we're comparing Ethernet headers and it's giving "tiny function, big networking energy." ✨

🌸 NAME

compare_ether_header — compare two Ethernet headers 🫶

✨ SYNOPSIS

unsigned long compare_ether_header (const void *a , const void *b );

🎀 ARGUMENTS

• a — pointer to an Ethernet header 💖
• b — pointer to an Ethernet header 💖

🔥 DESCRIPTION

This one compares two Ethernet headers and returns 0 if equal. Periodt. 💅

It assumes that the network header (i.e., the IP header) is 4-byte aligned OR that the platform can handle unaligned access. That's the case for all packets coming into netif_receive_skb or similar entry points. no cap, that's literally the contract. ✨

heads up bestie: this alignment / unaligned-access assumption is part of the whole vibe check for this function. 💀

👑 SEE ALSO

Kernel file ./include/linux/etherdevice.h — and the whole friend group:

• is_link_local_ether_addr(9)
• is_zero_ether_addr(9)
• is_multicast_ether_addr(9)
• is_local_ether_addr(9)
• is_broadcast_ether_addr(9)
• is_unicast_ether_addr(9)
• is_valid_ether_addr(9)
• eth_proto_is_802_3(9)
• eth_random_addr(9)
• eth_broadcast_addr(9)
• eth_zero_addr(9)
• eth_hw_addr_random(9)
• eth_hw_addr_crc(9)
• ether_addr_copy(9)
• eth_hw_addr_set(9)
• eth_hw_addr_inherit(9)
• ether_addr_equal(9)
• ether_addr_equal_64bits(9)
• ether_addr_equal_unaligned(9)
• ether_addr_equal_masked(9)
• ether_addr_to_u64(9)
• u64_to_ether_addr(9)
• eth_addr_dec(9)
• eth_addr_inc(9)
• eth_addr_add(9)
• is_etherdev_addr(9)
• eth_hw_addr_gen(9)
• eth_skb_pkt_type(9)
• eth_skb_pad(9)

cute little sign-off: this page's source sits in ./include/linux, dated October 2026 — that's the source/version-and-date situation, bestie, and compare_ether_header(9) is officially done. mwah 💋💖✨