#!/usr/bin/env python3 """Loopback integration of the optional TLS peer host and an ordinary Python client.""" import argparse import json from pathlib import Path import select import socket import ssl import struct import subprocess import tempfile def run(*args): subprocess.run(args, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL) def certificates(root): ca = root / 'ca.pem' run('openssl', 'req', '-x509', '-newkey', 'ec', '-pkeyopt', 'ec_paramgen_curve:P-256', '-nodes', '-days', '1', '-subj', '/CN=Pure test CA', '-addext', 'basicConstraints=critical,CA:TRUE', '-addext', 'keyUsage=critical,keyCertSign,cRLSign', '-keyout', root / 'ca.key', '-out', ca) for role, san, eku in [('server', 'localhost', 'serverAuth'), ('client', 'pure-client', 'clientAuth'), ('other', 'wrong-client', 'clientAuth')]: config = root / (role + '.ext') config.write_text(f'basicConstraints=critical,CA:FALSE\n' f'keyUsage=critical,digitalSignature\n' f'subjectAltName=DNS:{san}\nextendedKeyUsage={eku}\n') run('openssl', 'req', '-newkey', 'ec', '-pkeyopt', 'ec_paramgen_curve:P-256', '-nodes', '-subj', '/CN=' + san, '-keyout', root / (role + '.key'), '-out', root / (role + '.csr')) run('openssl', 'x509', '-req', '-in', root / (role + '.csr'), '-CA', ca, '-CAkey', root / 'ca.key', '-CAcreateserial', '-days', '1', '-extfile', config, '-out', root / (role + '.pem')) return ca def frame(payload): return struct.pack('!H', len(payload)) + payload def recv_exact(sock, size): result = bytearray() while len(result) < size: chunk = sock.recv(size - len(result)) if not chunk: raise EOFError('unexpected end of TLS stream') result += chunk return bytes(result) def receive(sock): size, = struct.unpack('!H', recv_exact(sock, 2)) return recv_exact(sock, size) def peer(root, ca, port, *, cert='client', alpn='pure/1', server_name='localhost'): ctx = ssl.create_default_context(cafile=str(ca)) ctx.minimum_version = ssl.TLSVersion.TLSv1_3 ctx.maximum_version = ssl.TLSVersion.TLSv1_3 if cert: ctx.load_cert_chain(str(root / (cert + '.pem')), str(root / (cert + '.key'))) ctx.set_alpn_protocols([alpn]) plain = socket.create_connection(('127.0.0.1', port), timeout=3) try: secure = ctx.wrap_socket(plain, server_hostname=server_name) secure.settimeout(3) return secure except BaseException: plain.close() raise def start(binary, root, ca, store): command = [str(binary), 'serve', '127.0.0.1', '0', str(store), 'scene', str(ca), str(root / 'server.pem'), str(root / 'server.key'), 'pure-client'] proc = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True, bufsize=1) try: assert select.select([proc.stdout], [], [], 5)[0], 'server did not become ready' line = proc.stdout.readline() assert line.startswith('READY '), (line, proc.stderr.read()) return proc, int(line.split()[1]) except BaseException: proc.kill() proc.wait(timeout=3) raise def stop(proc): proc.terminate() proc.communicate(timeout=5) assert proc.returncode == 0, proc.returncode def state(sock): sock.sendall(frame(b'\x00')) reply = receive(sock) assert len(reply) >= 26 and reply[0] == 0 revision, stored = struct.unpack_from('!QQ', reply, 1) assert len(reply) == 26 + 8 * reply[25] values = struct.unpack_from('!' + 'd' * reply[25], reply, 26) return revision, stored, values, struct.unpack_from('!I', reply, 21)[0] def rss_kib(pid): status = Path(f'/proc/{pid}/status') if not status.exists(): return None for line in status.read_text().splitlines(): if line.startswith('VmRSS:'): return int(line.split()[1]) return None def check(binary): with tempfile.TemporaryDirectory(prefix='pure-peer-check-') as tmp: root = Path(tmp) ca = certificates(root) server, port = start(binary, root, ca, root / 'store') idle_rss = rss_kib(server.pid) connected_rss = None try: # The peer is an ordinary Python TLS client: no Pure client library. with peer(root, ca, port) as sock: hello = receive(sock) assert len(hello) == 53 and hello[:4] == b'PUR1' revision, _, _, held = state(sock) connected_rss = rss_kib(server.pid) assert held == 0 stale = struct.pack('!BQ', 2, revision + 1) sock.sendall(frame(stale)) conflict = receive(sock) assert conflict[0] == 2 and struct.unpack_from('!Q', conflict, 1)[0] == revision assert state(sock)[0] == revision # Routed target zero; ending the session while held must cancel it. down = struct.pack('!BQBBBdd', 1, revision, 4, 0, 0, 90., 130.) sock.sendall(frame(down)) assert receive(sock)[0] == 0 with peer(root, ca, port) as sock: receive(sock) revision, _, values, held = state(sock) assert held == 0, (revision, values, held) # A malformed request and overlong frame close their sessions without mutation. for bad in [frame(b'\xff'), b'\x01\x00']: with peer(root, ca, port) as sock: receive(sock) sock.sendall(bad) try: assert sock.recv(2) == b'' except (ssl.SSLError, ConnectionResetError): pass with peer(root, ca, port) as sock: receive(sock) assert state(sock)[0] == revision # An authenticated client that sends nothing cannot retain the app forever. with peer(root, ca, port) as sock: receive(sock) sock.settimeout(7) try: assert sock.recv(1) == b'' except ssl.SSLError: pass with peer(root, ca, port) as sock: receive(sock) assert state(sock)[0] == revision # Authentication is mandatory on both sides; ALPN is mandatory too. for kwargs in [{'cert': None}, {'cert': 'other'}, {'alpn': 'http/1.1'}]: try: with peer(root, ca, port, **kwargs) as sock: receive(sock) except (ssl.SSLError, EOFError, ConnectionResetError, TimeoutError): pass else: raise AssertionError('untrusted or unsupported peer accepted: ' + str(kwargs)) try: peer(root, ca, port, server_name='wrong-server').close() except ssl.SSLError: pass else: raise AssertionError('wrong server name accepted') commands = 'point drag down green_box 90 130\npoint drag move green_box 230 210\npoint drag up green_box 230 210\nsave\nquit\n' result = subprocess.run([str(binary), 'call', '127.0.0.1', str(port), 'localhost', str(ca), str(root / 'client.pem'), str(root / 'client.key')], input=commands, text=True, capture_output=True, timeout=10) assert result.returncode == 0, (result.stdout, result.stderr) rows = [json.loads(line) for line in result.stdout.splitlines()] assert rows[-1]['status'] == 0 and rows[-1]['stored_revision'] == '1' assert rows[-1]['states']['green.x'] == 220 and rows[-1]['states']['green.y'] == 200 assert rows[-1]['held'] == 0 finally: stop(server) server, port = start(binary, root, ca, root / 'store') try: with peer(root, ca, port) as sock: receive(sock) _, stored, _, held = state(sock) assert stored == 1 and held == 0 result = subprocess.run([str(binary), 'call', '127.0.0.1', str(port), 'localhost', str(ca), str(root / 'client.pem'), str(root / 'client.key')], input='quit\n', text=True, capture_output=True, timeout=10) assert result.returncode == 0, (result.stdout, result.stderr) restored = json.loads(result.stdout.splitlines()[0]) assert restored['states']['green.x'] == 220 and restored['states']['green.y'] == 200 finally: stop(server) return {'python_client': 'pass', 'revision_conflict': 'pass', 'disconnect_release': 'pass', 'malformed_frames': 'pass', 'idle_deadline': 'pass', 'mutual_authentication': 'pass', 'alpn': 'pass', 'server_hostname': 'pass', 'persist_restart': 'pass', 'server_idle_rss_kib': idle_rss, 'server_connected_rss_kib': connected_rss} if __name__ == '__main__': parser = argparse.ArgumentParser(description=__doc__) parser.add_argument('binary', type=Path) args = parser.parse_args() print(json.dumps(check(args.binary.resolve()), sort_keys=True))