shred: expose merkle root for use in blockstore (#34063)

* shred: expose merkle root for use in blockstore

* pr feedback: sorted, keep Result return type

* convert Result<Hash> -> Option<Hash>

ledger/src/blockstore_meta.rs

@@ -406,6 +406,35 @@ impl ErasureMeta {
     }
 }
 
+#[allow(dead_code)]
+impl MerkleRootMeta {
+    pub(crate) fn from_shred(shred: &Shred) -> Self {
+        Self {
+            // An error here after the shred has already sigverified
+            // can only indicate that the leader is sending
+            // legacy or malformed shreds. We should still store
+            // `None` for those cases in blockstore, as a later
+            // shred that contains a proper merkle root would constitute
+            // a valid duplicate shred proof.
+            merkle_root: shred.merkle_root().ok(),
+            first_received_shred_index: shred.index(),
+            first_received_shred_type: shred.shred_type(),
+        }
+    }
+
+    pub(crate) fn merkle_root(&self) -> Option<Hash> {
+        self.merkle_root
+    }
+
+    pub(crate) fn first_received_shred_index(&self) -> u32 {
+        self.first_received_shred_index
+    }
+
+    pub(crate) fn first_received_shred_type(&self) -> ShredType {
+        self.first_received_shred_type
+    }
+}
+
 impl DuplicateSlotProof {
     pub(crate) fn new(shred1: Vec<u8>, shred2: Vec<u8>) -> Self {
         DuplicateSlotProof { shred1, shred2 }

ledger/src/shred.rs

@@ -334,6 +334,7 @@ impl Shred {
     dispatch!(pub(crate) fn erasure_shard_index(&self) -> Result<usize, Error>);
 
     dispatch!(pub fn into_payload(self) -> Vec<u8>);
+    dispatch!(pub fn merkle_root(&self) -> Result<Hash, Error>);
     dispatch!(pub fn payload(&self) -> &Vec<u8>);
     dispatch!(pub fn sanitize(&self) -> Result<(), Error>);
 

ledger/src/shred/merkle.rs

@@ -154,7 +154,7 @@ impl ShredData {
         Ok(Self::SIZE_OF_HEADERS + Self::capacity(proof_size)?)
     }
 
-    fn merkle_root(&self) -> Result<Hash, Error> {
+    pub(super) fn merkle_root(&self) -> Result<Hash, Error> {
         let proof_size = self.proof_size()?;
         let index = self.erasure_shard_index()?;
         let proof_offset = Self::proof_offset(proof_size)?;
@@ -266,7 +266,7 @@ impl ShredCode {
         Ok(Self::SIZE_OF_HEADERS + Self::capacity(proof_size)?)
     }
 
-    fn merkle_root(&self) -> Result<Hash, Error> {
+    pub(super) fn merkle_root(&self) -> Result<Hash, Error> {
         let proof_size = self.proof_size()?;
         let index = self.erasure_shard_index()?;
         let proof_offset = Self::proof_offset(proof_size)?;

ledger/src/shred/shred_code.rs

@@ -6,7 +6,7 @@ use {
         CodingShredHeader, Error, ShredCommonHeader, ShredType, SignedData,
         DATA_SHREDS_PER_FEC_BLOCK, MAX_DATA_SHREDS_PER_SLOT, SIZE_OF_NONCE,
     },
-    solana_sdk::{clock::Slot, packet::PACKET_DATA_SIZE, signature::Signature},
+    solana_sdk::{clock::Slot, hash::Hash, packet::PACKET_DATA_SIZE, signature::Signature},
     static_assertions::const_assert_eq,
 };
 
@@ -47,6 +47,13 @@ impl ShredCode {
         }
     }
 
+    pub(super) fn merkle_root(&self) -> Result<Hash, Error> {
+        match self {
+            Self::Legacy(_) => Err(Error::InvalidShredType),
+            Self::Merkle(shred) => shred.merkle_root(),
+        }
+    }
+
     pub(super) fn new_from_parity_shard(
         slot: Slot,
         index: u32,

ledger/src/shred/shred_data.rs

@@ -7,7 +7,7 @@ use {
         DataShredHeader, Error, ShredCommonHeader, ShredFlags, ShredType, ShredVariant, SignedData,
         MAX_DATA_SHREDS_PER_SLOT,
     },
-    solana_sdk::{clock::Slot, signature::Signature},
+    solana_sdk::{clock::Slot, hash::Hash, signature::Signature},
 };
 
 #[derive(Clone, Debug, Eq, PartialEq)]
@@ -41,6 +41,13 @@ impl ShredData {
         }
     }
 
+    pub(super) fn merkle_root(&self) -> Result<Hash, Error> {
+        match self {
+            Self::Legacy(_) => Err(Error::InvalidShredType),
+            Self::Merkle(shred) => shred.merkle_root(),
+        }
+    }
+
     pub(super) fn new_from_data(
         slot: Slot,
         index: u32,