Partial shred deserialize cleanup and shred type differentiation (#14094)

* Partial shred deserialize cleanup and shred type differentiation in retransmit

* consolidate packet hashing logic

core/src/packet_hasher.rs

@@ -0,0 +1,34 @@
+// Get a unique hash value for a packet
+// Used in retransmit and shred fetch to prevent dos with same packet data.
+
+use ahash::AHasher;
+use rand::{thread_rng, Rng};
+use solana_perf::packet::Packet;
+use std::hash::Hasher;
+
+#[derive(Clone)]
+pub struct PacketHasher {
+    seed1: u128,
+    seed2: u128,
+}
+
+impl Default for PacketHasher {
+    fn default() -> Self {
+        Self {
+            seed1: thread_rng().gen::<u128>(),
+            seed2: thread_rng().gen::<u128>(),
+        }
+    }
+}
+
+impl PacketHasher {
+    pub fn hash_packet(&self, packet: &Packet) -> u64 {
+        let mut hasher = AHasher::new_with_keys(self.seed1, self.seed2);
+        hasher.write(&packet.data[0..packet.meta.size]);
+        hasher.finish()
+    }
+
+    pub fn reset(&mut self) {
+        *self = Self::default();
+    }
+}