From 0b6ecbf06be16849b2bfff45c795fc9f54e6a6ec Mon Sep 17 00:00:00 2001
From: Sergey Belyakov <serg-belyakov@ydb.tech>
Date: Fri, 31 Oct 2025 11:15:30 +0300
Subject: [PATCH] Validate CrcMode of extreme queries in DSProxy and VDisk
 Skeleton (#27960)

---
 ydb/core/base/blobstorage.h                       |  2 ++
 ydb/core/blobstorage/vdisk/query/query_public.cpp |  9 +++++++++
 ydb/core/erasure/erasure.cpp                      | 10 ++++++++++
 ydb/core/erasure/erasure.h                        |  1 +
 4 files changed, 22 insertions(+)

diff --git a/ydb/core/base/blobstorage.h b/ydb/core/base/blobstorage.h
index 1ed0a65fc8dc..7c5d105f457b 100644
--- a/ydb/core/base/blobstorage.h
+++ b/ydb/core/base/blobstorage.h
@@ -1128,6 +1128,8 @@ struct TEvBlobStorage {
                 Y_ABORT_UNLESS(sh < id.BlobSize(),
                     "Please, don't read behind the end of the blob! BlobSize# %" PRIu32 " sh# %" PRIu32,
                     (ui32)id.BlobSize(), (ui32)sh);
+                Y_ABORT_UNLESS(TErasureType::IsCrcModeValid(id.CrcMode()),
+                        "Please, set correct CrcMode for query, CrcMode# %" PRIu32, id.CrcMode());
             }
 
             TString ToString() const {
diff --git a/ydb/core/blobstorage/vdisk/query/query_public.cpp b/ydb/core/blobstorage/vdisk/query/query_public.cpp
index 91fbaf4be64d..bbf8cd1df32e 100644
--- a/ydb/core/blobstorage/vdisk/query/query_public.cpp
+++ b/ydb/core/blobstorage/vdisk/query/query_public.cpp
@@ -138,6 +138,15 @@ namespace NKikimr {
             if (record.ExtremeQueriesSize() == 0)
                 return false; // we need to have one
 
+            for (const auto& query : record.GetExtremeQueries()) {
+                TLogoBlobID blobId = LogoBlobIDFromLogoBlobID(query.GetId());
+                if (!TErasureType::IsCrcModeValid(blobId.CrcMode())) {
+                    // We shouldn't be able to create TEvGet request with invalid CrcMode at all
+                    // something went wrong
+                    return false;
+                }
+            }
+
             return true;
         }
 
diff --git a/ydb/core/erasure/erasure.cpp b/ydb/core/erasure/erasure.cpp
index 21030ca7434f..a5c7550cdf5f 100644
--- a/ydb/core/erasure/erasure.cpp
+++ b/ydb/core/erasure/erasure.cpp
@@ -3206,6 +3206,16 @@ void TErasureType::RestoreData(ECrcMode crcMode, TDataPartSet& partSet, bool res
     }
 }
 
+bool TErasureType::IsCrcModeValid(ui32 crcModeRaw) {
+    switch (crcModeRaw) {
+    case static_cast<ui32>(ECrcMode::CrcModeNone):
+    case static_cast<ui32>(ECrcMode::CrcModeWholePart):
+        return true;
+    default:
+        return false;
+    }
+}
+
 } // NKikimr
 
 Y_DECLARE_OUT_SPEC(, NKikimr::TErasureType::EErasureSpecies, stream, value) {
diff --git a/ydb/core/erasure/erasure.h b/ydb/core/erasure/erasure.h
index 183584d2dc18..ffde4f28b604 100644
--- a/ydb/core/erasure/erasure.h
+++ b/ydb/core/erasure/erasure.h
@@ -369,6 +369,7 @@ struct TErasureType {
     ui64 BlockSplitPartUsedSize(ui64 dataSize, ui32 partIdx) const;
     ui32 BlockSplitPartIndex(ui64 offset, ui64 dataSize, ui64 &outPartOffset) const;
     ui64 BlockSplitWholeOffset(ui64 dataSize, ui64 partIdx, ui64 offset) const;
+    static bool IsCrcModeValid(ui32 crcModeRaw);
 
     static const std::array<TString, ErasureSpeciesCount> ErasureName;
 protected: