test: enable feature_bind_extra on macOS and BSD

`feature_bind_extra` checks `-bind` and `-whitebind` by comparing the node's listening sockets with the expected addresses.
Add `get_bind_addrs` support for macOS, FreeBSD, NetBSD, and OpenBSD using `lsof`, and switch the test to the POSIX platform guard so it runs there too.
On FreeBSD, pass `-Di` to avoid device-cache warnings on stderr that the functional test runner treats as failures.

Co-authored-by: willcl-ark <will8clark@gmail.com>
Co-authored-by: fanquake <fanquake@gmail.com>

test/functional/feature_bind_extra.py

@@ -32,8 +32,7 @@ class BindExtraTest(BitcoinTestFramework):
         self.num_nodes = 3
 
     def skip_test_if_missing_module(self):
-        # Due to OS-specific network stats queries, we only run on Linux.
-        self.skip_if_platform_not_linux()
+        self.skip_if_platform_not_posix()
 
     def setup_network(self):
         loopback_ipv4 = addr_to_hex("127.0.0.1")

test/functional/test_framework/netutil.py

@@ -2,7 +2,7 @@
 # Copyright (c) 2014-present The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
-"""Linux network utilities.
+"""Linux, macOS, and BSD network utilities.
 
 Roughly based on https://web.archive.org/web/20190424172231/http://voorloopnul.com/blog/a-python-netstat-in-less-than-100-lines-of-code/ by Ricardo Pascal
 """
@@ -88,12 +88,31 @@ def get_bind_addrs(pid):
     '''
     Get bind addresses as (host,port) tuples for process pid.
     '''
-    inodes = get_socket_inodes(pid)
-    bind_addrs = []
-    for conn in netstat('tcp') + netstat('tcp6'):
-        if conn[3] == STATE_LISTEN and conn[4] in inodes:
-            bind_addrs.append(conn[1])
-    return bind_addrs
+    if sys.platform == 'linux':
+        inodes = get_socket_inodes(pid)
+        bind_addrs = []
+        for conn in netstat('tcp') + netstat('tcp6'):
+            if conn[3] == STATE_LISTEN and conn[4] in inodes:
+                bind_addrs.append(conn[1])
+        return bind_addrs
+    elif sys.platform.startswith(("darwin", "freebsd", "netbsd", "openbsd")):
+        import re
+        import subprocess
+        output = subprocess.check_output(["lsof",
+            *(["-Di"] if sys.platform.startswith("freebsd") else []), # Ignore device cache to avoid stderr warnings.
+            "-nP",          # Keep hosts and ports numeric.
+            "-a",           # Require all filters to match.
+            "-p", str(pid), # Limit results to the target pid.
+            "-iTCP",        # Only inspect TCP sockets.
+            "-sTCP:LISTEN", # Only keep listening sockets.
+            "-Ftn",         # Emit machine-readable type and name fields.
+        ], text=True)
+        return [
+            (addr_to_hex(("::" if sock_type == "IPv6" else "0.0.0.0") if host == "*" else host.strip("[]")), int(port))
+            for sock_type, host, port in re.findall(r"t(IPv[46])\nn(\*|\[.+?]|[^:]+):(\d+)", output)
+        ]
+    else:
+        raise NotImplementedError(f"get_bind_addrs is not supported on {sys.platform}")
 
 # from: https://code.activestate.com/recipes/439093/
 def all_interfaces():