STRUCT LOWPAN_NHC(9)

✨ NAME ✨

struct lowpan_nhc — the lil struct that holds all the 6lowpan next hdr compression info 💅

🌸 SYNOPSIS 🌸

struct lowpan_nhc {
    const char      *name;
    u8 nexthdr;
    size_t nexthdrlen;
    u8 id;
    u8 idmask;
    int (*uncompress)(struct sk_buff *skb, size_t needed);
    int (*compress)(struct sk_buff *skb, u8 **hc_ptr);
 };

okay bestie, she's got seven fields and two of them are function pointers, so we're already in main character territory 🎀

💖 Members 💖

• name — the name of this specific next header compression. literally her government name, no cap 🫶
• nexthdr — the next header value of the protocol that's supposed to get compressed. this is the one we're squishing ✨
• nexthdrlen — the ipv6 nexthdr len for the reserved space. yes, you need the length too, don't skip it 🙈
• id — one byte nhc id value. one (1) single byte, she's compact, she's iconic 👑
• idmask — one byte nhc id mask value. also one byte. the mask does the matchy-matchy part, iykyk 🌈
• uncompress — callback that does the header uncompression. she expands the vibe back out 🦋
• compress — callback that does the header compression. and she squishes it down. two icons, opposite jobs, both slaying 💀

fr fr, both callbacks get a struct sk_buff *skb — keep that signature exactly as written, do not come for it 🫶

⭐ SEE ALSO ⭐

Kernel file ./net/6lowpan/nhc.h LOWPAN_NHC(9), lowpan_nhc_by_nexthdr(9), lowpan_nhc_check_compression(9), lowpan_nhc_do_compression(9), lowpan_nhc_do_uncompression(9), lowpan_nhc_add(9), lowpan_nhc_del(9), lowpan_nhc_init(9)

like the whole friend group, go read them too, they're all linked and they all ate 💜

and that's the page, bestie 🧚 from ./net/6lowpan, dated October 2026, and it's the struct lowpan_nhc(9) manual page — mwah, go compress some headers 💅💖