Basic "chain hardening" for slightly untrusted daemons (#93)

src/util/CMakeLists.txt

@@ -26,8 +26,8 @@
 # STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 # THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-set(monero-lws-util_sources gamma_picker.cpp random_outputs.cpp source_location.cpp transactions.cpp)
-set(monero-lws-util_headers fwd.h gamma_picker.h http_server.h random_outputs.h source_location.h transactions.h)
+set(monero-lws-util_sources blocks.cpp gamma_picker.cpp random_outputs.cpp source_location.cpp transactions.cpp)
+set(monero-lws-util_headers blocks.h fwd.h gamma_picker.h http_server.h random_outputs.h source_location.h transactions.h)
 
 add_library(monero-lws-util ${monero-lws-util_sources} ${monero-lws-util_headers})
-target_link_libraries(monero-lws-util monero::libraries)
+target_link_libraries(monero-lws-util monero::libraries monero-lws-db)

src/util/blocks.cpp

@@ -0,0 +1,87 @@
+// Copyright (c) 2024, The Monero Project
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "blocks.h"
+
+#include "cryptonote_config.h" // monero/src
+#include "crypto/hash-ops.h"   // monero/src
+#include "db/storage.h"
+#include "error.h"
+#include "misc_language.h"
+#include "string_tools.h"
+
+namespace lws
+{
+  crypto::hash get_block_longhash(
+    const std::string& bd, const db::block_id height, const unsigned major_version, const db::storage& disk, const db::block_id cached_start, epee::span<const crypto::hash> cached)
+  {
+    crypto::hash result{};
+
+    // block 202612 bug workaround
+    if (height == db::block_id(202612))
+    {
+      static const std::string longhash_202612 = "84f64766475d51837ac9efbef1926486e58563c95a19fef4aec3254f03000000";
+      epee::string_tools::hex_to_pod(longhash_202612, result);
+      return result;
+    }
+    if (major_version >= RX_BLOCK_VERSION)
+    {
+      crypto::hash hash{};
+      if (height != db::block_id(0))
+      {
+        const uint64_t seed_height = crypto::rx_seedheight(std::uint64_t(height));
+        if (cached_start <= db::block_id(seed_height))
+        {
+          if (cached.size() <= seed_height - std::uint64_t(cached_start))
+            MONERO_THROW(error::bad_blockchain, "invalid seed_height for cache or DB");
+          hash = cached[seed_height - std::uint64_t(cached_start)];
+        }
+        else
+          hash = MONERO_UNWRAP(MONERO_UNWRAP(disk.start_read()).get_block_hash(db::block_id(seed_height)));
+      }
+      else
+      {
+        memset(&result, 0, sizeof(crypto::hash));  // only happens when generating genesis block
+      }
+      crypto::rx_slow_hash(hash.data, bd.data(), bd.size(), result.data);
+    } else {
+      const int pow_variant = major_version >= 7 ? major_version - 6 : 0;
+      crypto::cn_slow_hash(bd.data(), bd.size(), result, pow_variant, std::uint64_t(height));
+    }
+    return result;
+  }
+
+  bool verify_timestamp(std::uint64_t check, std::vector<std::uint64_t> timestamps)
+  {
+    if (timestamps.empty())
+      return true;
+    if(check < epee::misc_utils::median(timestamps))
+      return false;
+    return true;
+  }
+}
+

src/util/blocks.h

@@ -0,0 +1,40 @@
+// Copyright (c) 2024, The Monero Project
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <string>
+#include "crypto/hash.h"
+#include "db/data.h"
+#include "db/fwd.h"
+#include "span.h" // in monero/contrib/epee/include
+
+namespace lws
+{
+  crypto::hash get_block_longhash(
+    const std::string& bd, const db::block_id height, const unsigned major_version, const db::storage& disk, db::block_id cached_start, epee::span<const crypto::hash> cached);
+
+  bool verify_timestamp(std::uint64_t verify, std::vector<std::uint64_t> timestamps);
+}