STRUCT NFT_CHAIN(9)

💅 struct nft_chain(9) — the Kernel API Manual glow-up 🎀

okay so bestie, we're in the struct nft_chain(9) page rn — a whole kernel API manual page, and honestly? it's giving main character energy. this is the nf_tables chain, and i'm gonna walk you through every single field like we're doing a vibe check on each one. no skipping, no cap. ✨

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🦋 NAME 🦋

struct nft_chain — literally the nf_tables chain, that's her, that's the whole thing 💖

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✨ SYNOPSIS ✨

like, here's her whole personality laid out, character for character, don't @ me:

struct nft_chain {
    struct nft_rule_blob            *blob_gen_0;
    struct nft_rule_blob            *blob_gen_1;
    struct list_head                rules;
    struct list_head                list;
    struct rhlist_head              rhlhead;
    struct nft_table                *table;
    u64 handle;
    u32 use;
    u8 flags:5, bound:1, genmask:2;
    char *name;
    u16 udlen;
    u8 *udata;
    struct nft_rule_blob            *blob_next;
    struct nft_chain_validate_state vstate;
 };

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🌸 Members 🌸

okay this is the fun part, let's meet the cast 🫶

• blob_gen_0 — rule blob pointer to the current generation. she's the present, she's now, she's living her truth 🔥
• blob_gen_1 — rule blob pointer to the future generation. manifesting ✨
• rules — list of rules in the chain. the whole squad, in order 💅
• list — used internally. not your business bestie, it's giving backstage 🎀
• rhlhead — used internally. also backstage, also not your business 🙈
• table — table that this chain belongs to. found family 💜
• handle — chain handle. her little ID badge 🪪
• use — number of jump references to this chain. how many people are jumping to her, iconic behavior 👑
• flags — bitmask of enum NFTA_CHAIN_FLAGS. tiny bitmask, huge personality 🌈
• bound — bind or not. binary queen, she either is or she isn't 💀
• genmask — generation mask. time-travel makeup 🧚
• name — name of the chain. yes she has a name, say it with your chest ⭐
• udlen — user data length. how much user data, numerically speaking 🍓
• udata — user data in the chain. her personal lore 🦋
• blob_next — rule blob pointer to the next in the chain. linked-list slay, periodt 💖
• vstate — validation state. she's getting checked and she's passing, obviously ✅

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🔥 SEE ALSO 🔥

okay so like, the whole friend group, no gatekeeping. Kernel file ./include/net/netfilter/nf_tables.h, plus every one of these icons:

struct nft_verdict(9), struct nft_regs(9), struct nft_ctx(9), struct nft_userdata(9), struct nft_set_elem(9), enum nft_iter_type(9), struct nft_set_desc(9), enum nft_set_class(9), struct nft_set_estimate(9), struct nft_expr(9), struct nft_set_ops(9), struct nft_set_type(9), struct nft_set(9), struct nft_set_binding(9), enum nft_set_extensions(9), struct nft_set_ext_type(9), struct nft_set_ext_tmpl(9), struct nft_set_ext(9), struct nft_expr_type(9), struct nft_expr_ops(9), struct nft_rule(9), struct nft_chain_validate_state(9), struct nft_chain_type(9), struct nft_base_chain(9), struct nft_table(9), struct nft_object_hash_key(9), struct nft_object(9), struct nft_object_type(9), struct nft_object_ops(9), struct nft_flowtable(9), struct nft_traceinfo(9), struct nft_trans(9), struct nft_trans_hook(9), struct nft_trans_binding(9)

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ngl, that's a lot of structs. read them all, bestie, they're all connected iykyk 😭

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and that's the whole page, no crumbs left 💀 this baby lives under ./include/net/netfilter, it's from October 2026, and it's filed under struct nft_chain(9). slay, go read nf_tables.h now, mwah 💖🎀✨