From e80bd36f769794349a1b4fc83eaa6869731bbf5e Mon Sep 17 00:00:00 2001
From: Agnish Ghosh <iamagnix@gmail.com>
Date: Fri, 26 Jul 2024 14:19:44 +0530
Subject: [PATCH] add: verify data column kzg proof during storeBlock, added
 serializeDataColumn for better logs

---
 .../gossip_processing/block_processor.nim     | 18 ++++++++++++++++++
 beacon_chain/spec/datatypes/eip7594.nim       | 19 ++++++++++++++++---
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/beacon_chain/gossip_processing/block_processor.nim b/beacon_chain/gossip_processing/block_processor.nim
index 8fdd7460e..79a526478 100644
--- a/beacon_chain/gossip_processing/block_processor.nim
+++ b/beacon_chain/gossip_processing/block_processor.nim
@@ -644,6 +644,24 @@ proc storeBlock(
             msg = r.error()
           return err((VerifierError.Invalid, ProcessingStatus.completed))
 
+    if dataColumnsOpt.isSome:
+      let data_column_sidecars = dataColumnsOpt.get
+      if data_column_sidecars.len > 0:
+        for i in 0..<data_column_sidecars.len:
+          let r = verify_data_column_sidecar_kzg_proofs(data_column_sidecars[i][])
+
+          if r.isErr():
+            debug "data column sidecar verification failed",
+              blockroot = shortLog(signedBlock.root),
+              column = shortLog(data_column_sidecars[i][].column),
+              blck = shortLog(signedBlock.message),
+              kzgCommits = 
+                mapIt(data_column_sidecars[i][].kzg_commitments,
+                      shortLog(it)),
+              signature = shortLog(signedBlock.signature),
+              msg = r.error
+            return err((VerifierError.Invalid, ProcessingStatus.completed))
+
   type Trusted = typeof signedBlock.asTrusted()
 
   let
diff --git a/beacon_chain/spec/datatypes/eip7594.nim b/beacon_chain/spec/datatypes/eip7594.nim
index 5a4f21140..627ac8b0e 100644
--- a/beacon_chain/spec/datatypes/eip7594.nim
+++ b/beacon_chain/spec/datatypes/eip7594.nim
@@ -7,9 +7,11 @@
 
 {.push raises: [].}
 
-import 
+import
+  std/[sequtils],
   "."/[base, deneb], 
-  kzg4844
+  kzg4844,
+  stew/[byteutils]
 
 from std/sequtils import mapIt
 from std/strutils import join
@@ -64,7 +66,7 @@ type
 
   DataColumnSidecars* = seq[ref DataColumnSidecar]
 
-  DataColumnIdentifier* = object 
+  DataColumnIdentifier* = object
     block_root*: Eth2Digest
     index*: ColumnIndex
 
@@ -76,6 +78,17 @@ type
 
   CscBits* = BitArray[DATA_COLUMN_SIDECAR_SUBNET_COUNT]
 
+func serializeDataColumn(data_column: DataColumn): auto =
+  var counter = 0
+  var serd : array[MAX_BLOB_COMMITMENTS_PER_BLOCK * KzgCellSize, byte]
+  for i in 0..<MAX_BLOB_COMMITMENTS_PER_BLOCK:
+    for j in 0..<KzgCellSize:
+      serd[counter] = data_column[i][j]
+      inc(counter)
+  serd
+
+func shortLog*(v: DataColumn): auto =
+  to0xHex(v.serializeDataColumn())
 
 func shortLog*(v: DataColumnSidecar): auto =
   (