STRUCT FLOW_DISSECTOR_KEY_ICMP(9)

🦋 NAME 🦋

struct flow_dissector_key_icmp — okay so bestie, the official one-liner here is literally blank (not me exposing the kernel docs 😭), but this is the struct that holds your ICMP type/code and session id for the flow dissector. She's small, she's iconic, she does one job 💅

✨ SYNOPSIS ✨

Like, here's the whole vibe, verbatim, no cap:

struct flow_dissector_key_icmp {
    struct {
      u8 type;
      u8 code;
    };
    u16 id;
 };

yes the anonymous nested struct is doing main character energy, we'll get to her 🫶

🎀 Members 🎀

• {unnamed_struct} — the anonymous one 💀 she has no name, she simply is. Lowkey mysterious, highkey doing the actual work.
• type — the ICMP type. this is the "what kind of ICMP message is this" field, fr fr.
• code — the ICMP code. the little sub-flavour that goes with the type, iykyk.
• id — the session identifier. her job is matching packets to their session, and she ate. 👑

🌈 SEE ALSO 🌈

So the whole squad lives in the Kernel file ./include/net/flow_dissector.h struct, and here's every single sibling — not skipping a one, bestie, we list them all:

• struct flow_dissector_key_control(9)
• struct flow_dissector_key_basic(9)
• struct flow_dissector_key_enc_opts(9)
• struct flow_dissector_key_ipv4_addrs(9)
• struct flow_dissector_key_ipv6_addrs(9)
• struct flow_dissector_key_tipc(9)
• struct flow_dissector_key_addrs(9)
• struct flow_dissector_key_arp(9)
• struct flow_dissector_key_ports(9)
• struct flow_dissector_key_ports_range(9)
• struct flow_dissector_key_eth_addrs(9)
• struct flow_dissector_key_tcp(9)
• struct flow_dissector_key_ip(9)
• struct flow_dissector_key_meta(9)
• struct flow_dissector_key_ct(9)
• struct flow_dissector_key_hash(9)
• struct flow_dissector_key_num_of_vlans(9)
• struct flow_dissector_key_pppoe(9)
• struct flow_dissector_key_l2tpv3(9)
• struct flow_dissector_key_ipsec(9)
• struct flow_dissector_key_cfm(9)

go read them all, they're all part of the same flow-dissector friend group and honestly? iconic lineup 💖

that's the whole page, babe ✨ this came from ./include/net, dated October 2026, straight out of the Kernel API Manual — mwah, go dissect some flows, you've got this 🧚💜