Merge #17812: config, net, test: asmap feature refinements and functional tests

1ba3e1cc21150abe632a5b82a1a38998b33815dc init: move asmap code earlier in init process (Jon Atack)
5ba829e12e99f119df56cab422f827b9be03fe57 rpc: fix getpeerinfo RPCResult `mapped_as` type (Jon Atack)
c90b9a2399f4cead37bad39f388ce1255e123dc4 net: extract conditional to bool CNetAddr::IsHeNet (Jon Atack)
819fb5549b0d02477f47b3c40338071f37b6d885 logging: asmap logging and #include fixups (Jon Atack)
dcaf543ba0241f9219cea70b67c7b066d4c9ca9b test: add functional test for an empty, unparsable asmap (Jon Atack)
b8d0412b213df18f23bf8677ab94068c6cca9f51 config: separate the asmap finding and parsing checks (Jon Atack)
81c38a24975f34e5894efe3d1aaf45ff6a8cee4a config: enable passing -asmap an absolute file path (Jon Atack)
fbe9b024f01c29153afe494fed74b623ce3ffefa config: use default value in -asmap config (Jon Atack)
08b992675cf8d946db19b7bea747fa1085fdb2a2 test: add feature_asmap functional tests (Jon Atack)

Pull request description:

  This PR builds on PR #16702 to add functional tests / sanity checks and user-facing refinements for passing `-asmap` to configure ASN-based IP bucketing in addrman. As per our review discussion in that PR, the idea here is to handle aspects like functional tests and config arg handling that can help the PR be merged while enabling the author to focus on the bucketing itself.

  - [x] add feature functional tests to verify node behaviour and debug log output when launching

    - `bitcoind` with no `-asmap` arg

    - `bitcoind -asmap=RELATIVE_FILENAME` to the unit test data skeleton asmap

    - `bitcoind -asmap` with no filename specified using the default asmap file

    - `bitcoind -asmap` with no filename specified and a missing default asmap file

  - [x] add the ability to pass absolute path filenames to the `-asmap` config arg in addition to datadir-relative path filenames as per https://github.com/bitcoin/bitcoin/pull/16702#discussion_r361300447, and add test coverage

  - [x] separate the asmap file finding and parsing checks, which allows adding tests for the case of a found but unparseable or empty asmap

  - [x] add test for an empty asmap

  - [x] various asmap fixups

  - [x] move the asmap init code earlier in the init process to provide immediate feedback when passing an  `-asmap` config arg. This speeds up the `feature_asmap` functional test from 60 to 5 seconds! Credit to Wladimir J. van der Laan for the suggestion.

ACKs for top commit:
  practicalswift:
    ACK 1ba3e1cc21150abe632a5b82a1a38998b33815dc -- diff looks correct
  fanquake:
    ACK 1ba3e1cc21150abe632a5b82a1a38998b33815dc

Tree-SHA512: e9094460a597ac5597449acfe631c87b71d3ede6a12c7ae61b26d1161b3eefed8e7e25c4fb0505864cebd89300b7c4cf9378060aa9155441029315df15fa3283

2 files changed, 107 insertions, 0 deletions

diff --git a/test/functional/feature_asmap.py b/test/functional/feature_asmap.py
new file mode 100755
index 0000000000..2c6553fbe2
--- /dev/null
+++ b/test/functional/feature_asmap.py
@@ -0,0 +1,106 @@
+#!/usr/bin/env python3
+# Copyright (c) 2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Test asmap config argument for ASN-based IP bucketing.
+
+Verify node behaviour and debug log when launching bitcoind in these cases:
+
+1. `bitcoind` with no -asmap arg, using /16 prefix for IP bucketing
+
+2. `bitcoind -asmap=<absolute path>`, using the unit test skeleton asmap
+
+3. `bitcoind -asmap=<relative path>`, using the unit test skeleton asmap
+
+4. `bitcoind -asmap/-asmap=` with no file specified, using the default asmap
+
+5. `bitcoind -asmap` with no file specified and a missing default asmap file
+
+6. `bitcoind -asmap` with an empty (unparsable) default asmap file
+
+The tests are order-independent.
+
+"""
+import os
+import shutil
+
+from test_framework.test_framework import BitcoinTestFramework
+
+DEFAULT_ASMAP_FILENAME = 'ip_asn.map' # defined in src/init.cpp
+ASMAP = '../../src/test/data/asmap.raw' # path to unit test skeleton asmap
+VERSION = 'fec61fa21a9f46f3b17bdcd660d7f4cd90b966aad3aec593c99b35f0aca15853'
+
+def expected_messages(filename):
+    return ['Opened asmap file "{}" (59 bytes) from disk'.format(filename),
+            'Using asmap version {} for IP bucketing'.format(VERSION)]
+
+class AsmapTest(BitcoinTestFramework):
+    def set_test_params(self):
+        self.setup_clean_chain = False
+        self.num_nodes = 1
+
+    def test_without_asmap_arg(self):
+        self.log.info('Test bitcoind with no -asmap arg passed')
+        self.stop_node(0)
+        with self.node.assert_debug_log(['Using /16 prefix for IP bucketing']):
+            self.start_node(0)
+
+    def test_asmap_with_absolute_path(self):
+        self.log.info('Test bitcoind -asmap=<absolute path>')
+        self.stop_node(0)
+        filename = os.path.join(self.datadir, 'my-map-file.map')
+        shutil.copyfile(self.asmap_raw, filename)
+        with self.node.assert_debug_log(expected_messages(filename)):
+            self.start_node(0, ['-asmap={}'.format(filename)])
+        os.remove(filename)
+
+    def test_asmap_with_relative_path(self):
+        self.log.info('Test bitcoind -asmap=<relative path>')
+        self.stop_node(0)
+        name = 'ASN_map'
+        filename = os.path.join(self.datadir, name)
+        shutil.copyfile(self.asmap_raw, filename)
+        with self.node.assert_debug_log(expected_messages(filename)):
+            self.start_node(0, ['-asmap={}'.format(name)])
+        os.remove(filename)
+
+    def test_default_asmap(self):
+        shutil.copyfile(self.asmap_raw, self.default_asmap)
+        for arg in ['-asmap', '-asmap=']:
+            self.log.info('Test bitcoind {} (using default map file)'.format(arg))
+            self.stop_node(0)
+            with self.node.assert_debug_log(expected_messages(self.default_asmap)):
+                self.start_node(0, [arg])
+        os.remove(self.default_asmap)
+
+    def test_default_asmap_with_missing_file(self):
+        self.log.info('Test bitcoind -asmap with missing default map file')
+        self.stop_node(0)
+        msg = "Error: Could not find asmap file \"{}\"".format(self.default_asmap)
+        self.node.assert_start_raises_init_error(extra_args=['-asmap'], expected_msg=msg)
+
+    def test_empty_asmap(self):
+        self.log.info('Test bitcoind -asmap with empty map file')
+        self.stop_node(0)
+        with open(self.default_asmap, "w", encoding="utf-8") as f:
+            f.write("")
+        msg = "Error: Could not parse asmap file \"{}\"".format(self.default_asmap)
+        self.node.assert_start_raises_init_error(extra_args=['-asmap'], expected_msg=msg)
+        os.remove(self.default_asmap)
+
+    def run_test(self):
+        self.node = self.nodes[0]
+        self.datadir = os.path.join(self.node.datadir, self.chain)
+        self.default_asmap = os.path.join(self.datadir, DEFAULT_ASMAP_FILENAME)
+        self.asmap_raw = os.path.join(os.path.dirname(os.path.realpath(__file__)), ASMAP)
+
+        self.test_without_asmap_arg()
+        self.test_asmap_with_absolute_path()
+        self.test_asmap_with_relative_path()
+        self.test_default_asmap()
+        self.test_default_asmap_with_missing_file()
+        self.test_empty_asmap()
+
+
+if __name__ == '__main__':
+    AsmapTest().main()
diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py
index 06d939afb7..2036d20852 100755
--- a/test/functional/test_runner.py
+++ b/test/functional/test_runner.py
@@ -206,6 +206,7 @@ BASE_SCRIPTS = [
     'p2p_dos_header_tree.py',
     'p2p_unrequested_blocks.py',
     'feature_includeconf.py',
+    'feature_asmap.py',
     'rpc_deriveaddresses.py',
     'rpc_deriveaddresses.py --usecli',
     'rpc_scantxoutset.py',