Function solana_ledger::sigverify_shreds::verify_shred_cpu

pub fn verify_shred_cpu(
    packet: &Packet, 
    slot_leaders: &HashMap<u64, [u8; 32]>
) -> Option<u8>

Assuming layout is signature: Signature signed_msg: { type: ShredType slot: u64, … } Signature is the first thing in the packet, and slot is the first thing in the signed message.