From aa6073bee8007b396a50cb2b47c830490173ae27 Mon Sep 17 00:00:00 2001
From: "mergify[bot]" <37929162+mergify[bot]@users.noreply.github.com>
Date: Wed, 15 Feb 2023 23:34:28 +0000
Subject: [PATCH] v1.15: adds hash domain to merkle shreds (backport of #29339)
 (#30346)

adds hash domain to merkle shreds (#29339)

(cherry picked from commit 06bb71c79fca73ebbf3a2d4bbbc87890adc4e9c7)

Co-authored-by: behzad nouri <behzadnouri@gmail.com>
---
 ledger/src/shred/merkle.rs | 6 ++++--
 ledger/src/shredder.rs     | 4 +---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/ledger/src/shred/merkle.rs b/ledger/src/shred/merkle.rs
index 179388b4fb7b70..10646edd39fae8 100644
--- a/ledger/src/shred/merkle.rs
+++ b/ledger/src/shred/merkle.rs
@@ -41,8 +41,10 @@ const_assert_eq!(ShredData::SIZE_OF_PAYLOAD, 1203);
 
 // Defense against second preimage attack:
 // https://en.wikipedia.org/wiki/Merkle_tree#Second_preimage_attack
-const MERKLE_HASH_PREFIX_LEAF: &[u8] = &[0x00];
-const MERKLE_HASH_PREFIX_NODE: &[u8] = &[0x01];
+// Following Certificate Transparency, 0x00 and 0x01 bytes are prepended to
+// hash data when computing leaf and internal node hashes respectively.
+const MERKLE_HASH_PREFIX_LEAF: &[u8] = b"\x00SOLANA_MERKLE_SHREDS_LEAF";
+const MERKLE_HASH_PREFIX_NODE: &[u8] = b"\x01SOLANA_MERKLE_SHREDS_NODE";
 
 type MerkleProofEntry = [u8; 20];
 
diff --git a/ledger/src/shredder.rs b/ledger/src/shredder.rs
index 6c1e6b0b4c6e64..9ef0a68fdc5c08 100644
--- a/ledger/src/shredder.rs
+++ b/ledger/src/shredder.rs
@@ -7,7 +7,7 @@ use {
     lru::LruCache,
     rayon::{prelude::*, ThreadPool},
     reed_solomon_erasure::{
-        galois_8::Field,
+        galois_8::ReedSolomon,
         Error::{InvalidIndex, TooFewDataShards, TooFewShardsPresent},
     },
     solana_entry::entry::Entry,
@@ -38,8 +38,6 @@ pub(crate) const ERASURE_BATCH_SIZE: [usize; 33] = [
     55, 56, 58, 59, 60, 62, 63, 64, // 32
 ];
 
-type ReedSolomon = reed_solomon_erasure::ReedSolomon<Field>;
-
 pub struct ReedSolomonCache(
     Mutex<LruCache<(/*data_shards:*/ usize, /*parity_shards:*/ usize), Arc<ReedSolomon>>>,
 );