batadv_skb_decrement_ttl(9)

💅 batadv_skb_decrement_ttl(9) 💅

okay so bestie, this is a page from the Kernel API Manual about batadv_skb_decrement_ttl — and honestly? she's a tiny function with main character energy. buckle up 🎀

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✨ NAME ✨

batadv_skb_decrement_ttl — decrements the ttl inside a batman-adv header, and does it csum-safe. like, it doesn't wreck your checksums. queen behavior 👑

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🌸 SYNOPSIS 🌸

bool batadv_skb_decrement_ttl(struct sk_buff *skb);

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🦋 ARGUMENTS 🦋

• skb — the received packet, and listen: skb->data has to be pointing at the batman-adv header. that's the whole vibe check fr fr 🫶

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🔥 DESCRIPTION 🔥

she supports a whole lineup of packet types, and every single one of them carries the TTL at offset 2. no cap, offset 2 for all of them. iconic consistency 💖

• batadv_ogm_packet
• batadv_ogm2_packet
• batadv_icmp_header
• batadv_icmp_packet
• batadv_icmp_tp_packet
• batadv_icmp_packet_rr
• batadv_unicast_packet
• batadv_frag_packet
• batadv_bcast_packet
• batadv_mcast_packet
• batadv_coded_packet
• batadv_unicast_tvlv_packet

twelve packet types, all ate, no crumbs 🌈

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⭐ RETURN ⭐

• true — the packet may be forwarded, because the ttl got decremented. slay, she's still alive 💅
• false — the packet must be dropped, because the ttl would expire. rip bestie, she's done 😭

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💜 SEE ALSO 💜

all the routing.c girlies, from the kernel file ./net/batman-adv/routing.c:

• _batadv_update_route(9)
• batadv_update_route(9)
• batadv_window_protected(9)
• batadv_check_management_packet(9)
• batadv_recv_my_icmp_packet(9)
• batadv_recv_icmp_ttl_exceeded(9)
• batadv_recv_icmp_packet(9)
• batadv_check_unicast_packet(9)
• batadv_last_bonding_get(9)
• batadv_last_bonding_replace(9)
• batadv_find_router(9)
• batadv_route_unicast_packet(9)
• batadv_reroute_unicast_packet(9)
• batadv_check_unicast_ttvn(9)
• batadv_recv_unhandled_unicast_packet(9)
• batadv_recv_unicast_packet(9)
• batadv_recv_unicast_tvlv(9)
• batadv_recv_frag_packet(9)
• batadv_recv_bcast_packet(9)
• batadv_recv_mcast_packet(9)

go read them, iykyk 🧚

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and that's the whole page, bestie! this one comes to you live from ./net/batman-adv, dated October 2026 — the manual name is batadv_skb_decrement_ttl(9) in case you forgot already 🙈 mwah, go forward those packets responsibly 💋💖