Merge pull request #303 from evoskuil/version3

Backport master/v4 commits for version3/v3.1 release.

Author: evoskuil

src/protocols/protocol_block_in.cpp

@@ -157,8 +157,6 @@ void protocol_block_in::handle_fetch_block_locator(const code& ec,
     if (stopped(ec))
         return;
 
-    const auto& last_hash = message->start_hashes().front();
-
     if (ec)
     {
         LOG_ERROR(LOG_NODE)
@@ -171,14 +169,25 @@ void protocol_block_in::handle_fetch_block_locator(const code& ec,
     if (message->start_hashes().empty())
         return;
 
+    const auto& last_hash = message->start_hashes().front();
+
     // TODO: move get_headers to a derived class protocol_block_in_31800.
     const auto use_headers = negotiated_version() >= version::level::headers;
-    const auto default_size = use_headers ? "2000" : "500";
+    const auto request_type = (use_headers ? "headers" : "inventory");
 
-    LOG_DEBUG(LOG_NODE)
-        << "Ask [" << authority() << "] for headers from ["
-        << encode_hash(last_hash) << "] through [" <<
-        (stop_hash == null_hash ? default_size : encode_hash(stop_hash)) << "]";
+    if (stop_hash == null_hash)
+    {
+        LOG_DEBUG(LOG_NODE)
+            << "Ask [" << authority() << "] for " << request_type << " after ["
+            << encode_hash(last_hash) << "]";
+    }
+    else
+    {
+        LOG_DEBUG(LOG_NODE)
+            << "Ask [" << authority() << "] for " << request_type << " from ["
+            << encode_hash(last_hash) << "] through ["
+            << encode_hash(stop_hash) << "]";
+    }
 
     // Save the locator top to prevent a redundant future request.
     last_locator_top_.store(last_hash);
@@ -202,6 +211,15 @@ bool protocol_block_in::handle_receive_headers(const code& ec,
     if (stopped(ec))
         return false;
 
+    // We don't want to request a batch of headers out of order.
+    if (!message->is_sequential())
+    {
+        LOG_WARNING(LOG_NODE)
+            << "Block headers out of order from [" << authority() << "].";
+        stop(error::channel_stopped);
+        return false;
+    }
+
     // There is no benefit to this use of headers, in fact it is suboptimal.
     // In v3 headers will be used to build block tree before getting blocks.
     const auto response = std::make_shared<get_data>();

src/protocols/protocol_transaction_in.cpp

@@ -51,7 +51,11 @@ protocol_transaction_in::protocol_transaction_in(full_node& node,
     chain_(chain),
 
     // TODO: move relay to a derived class protocol_transaction_in_70001.
-    relay_from_peer_(node.network_settings().relay_transactions),
+    // In the mean time, restrict by negotiated protocol level.
+    // Because of inconsistent implementation by version we must allow relay
+    // at bip37 version or below. Enforcement starts above bip37 version.
+    relay_from_peer_(negotiated_version() <= version::level::bip37 ||
+        node.network_settings().relay_transactions),
 
     // TODO: move memory_pool to a derived class protocol_transaction_in_60002.
     refresh_pool_(negotiated_version() >= version::level::bip35 &&