Merge bitcoin/bitcoin#22362: Drop only invalid entries when reading banlist.json

faa6c3d44c net: Drop only invalid entries when reading banlist.json (MarcoFalke)

Pull request description:

  All entries will be dropped when there is at least one invalid one in `banlist.json`. Fix this by only dropping invalid ones.

  Also suggested in https://github.com/bitcoin/bitcoin/pull/20966#issuecomment-861150204

ACKs for top commit:
  laanwj:
    Re-ACK faa6c3d44c

Tree-SHA512: 5a58e7f1dcabf78d0c65d8c6d5d997063af1efeaa50ca7730fc00056fda7e0061b6f7a38907ea045fe667c9f61d392e01e556b425a95e6b126e3c41cd33deb83

src/test/banman_tests.cpp

@@ -0,0 +1,43 @@
+// Copyright (c) 2021 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <banman.h>
+#include <chainparams.h>
+#include <netbase.h>
+#include <streams.h>
+#include <test/util/logging.h>
+#include <test/util/setup_common.h>
+#include <util/readwritefile.h>
+
+
+#include <boost/test/unit_test.hpp>
+
+BOOST_FIXTURE_TEST_SUITE(banman_tests, BasicTestingSetup)
+
+BOOST_AUTO_TEST_CASE(file)
+{
+    SetMockTime(777s);
+    const fs::path banlist_path{m_args.GetDataDirBase() / "banlist_test"};
+    {
+        const std::string entries_write{
+            "{ \"banned_nets\": ["
+            "  { \"version\": 1, \"ban_created\": 0, \"banned_until\": 778, \"address\": \"aaaaaaaaa\" },"
+            "  { \"version\": 2, \"ban_created\": 0, \"banned_until\": 778, \"address\": \"bbbbbbbbb\" },"
+            "  { \"version\": 1, \"ban_created\": 0, \"banned_until\": 778, \"address\": \"1.0.0.0/8\" }"
+            "] }",
+        };
+        assert(WriteBinaryFile(banlist_path + ".json", entries_write));
+        {
+            // The invalid entries will be dropped, but the valid one remains
+            ASSERT_DEBUG_LOG("Dropping entry with unparseable address or subnet (aaaaaaaaa) from ban list");
+            ASSERT_DEBUG_LOG("Dropping entry with unknown version (2) from ban list");
+            BanMan banman{banlist_path, /*client_interface=*/nullptr, /*default_ban_time=*/0};
+            banmap_t entries_read;
+            banman.GetBanned(entries_read);
+            assert(entries_read.size() == 1);
+        }
+    }
+}
+
+BOOST_AUTO_TEST_SUITE_END()