wire: add tests for v1 codec

src/tests/test_wire_codec_v1.py

@@ -0,0 +1,180 @@
+import sys
+sys.path.append('..')
+sys.path.append('../lib')
+import unittest
+import ustruct
+
+from trezor.wire import wire_codec_v1
+from trezor.utils import chunks
+from trezor.crypto import random
+
+
+class TestWireCodecV1(unittest.TestCase):
+    # pylint: disable=C0301
+
+    def test_detect(self):
+        for i in range(0, 256):
+            if i == ord(b'?'):
+                self.assertTrue(wire_codec_v1.detect_v1(bytes([i]) + b'\x00' * 63))
+            else:
+                self.assertFalse(wire_codec_v1.detect_v1(bytes([i]) + b'\x00' * 63))
+
+    def test_parse(self):
+        d = bytes(range(0, 55))
+        m = b'##\x00\x00\x00\x00\x00\x37' + d
+        r = b'?' + m
+
+        rm, rs, rd = wire_codec_v1.parse_report_v1(r)
+        self.assertEqual(rm, None)
+        self.assertEqual(rs, 0)
+        self.assertEqual(rd, m)
+
+        mt, ml, md = wire_codec_v1.parse_message(m)
+        self.assertEqual(mt, 0)
+        self.assertEqual(ml, len(d))
+        self.assertEqual(md, d)
+
+        for i in range(0, 1024):
+            if i != 64:
+                with self.assertRaises(ValueError):
+                    wire_codec_v1.parse_report_v1(bytes(range(0, i)))
+
+        for hx in range(0, 256):
+            for hy in range(0, 256):
+                if hx != ord(b'#') and hy != ord(b'#'):
+                    with self.assertRaises(ValueError):
+                        wire_codec_v1.parse_message(bytes([hx, hy]) + m[2:])
+
+    def test_serialize(self):
+        data = bytearray(range(0, 10))
+        wire_codec_v1.serialize_message_header(data, 0x1234, 0x56789abc)
+        self.assertEqual(data, b'\x00##\x12\x34\x56\x78\x9a\xbc\x09')
+
+        data = bytearray(9)
+        with self.assertRaises(ValueError):
+            wire_codec_v1.serialize_message_header(data, 65536, 0)
+
+        for i in range(0, 8):
+            data = bytearray(i)
+            with self.assertRaises(ValueError):
+                wire_codec_v1.serialize_message_header(data, 0x1234, 0x56789abc)
+
+    def test_decode_empty(self):
+        message = b'##' + b'\xab\xcd' + b'\x00\x00\x00\x00' + b'\x00' * 55
+
+        record = []
+        genfunc = self._record(record, 0xabcd, 0, 0xdeadbeef, 'dummy')
+        decoder = wire_codec_v1.decode_wire_v1_stream(genfunc, 0xdeadbeef, 'dummy')
+        decoder.send(None)
+
+        try:
+            decoder.send(message)
+        except StopIteration as e:
+            res = e.value
+        self.assertEqual(res, None)
+        self.assertEqual(len(record), 1)
+        self.assertIsInstance(record[0], EOFError)
+
+    def test_decode_one_report_aligned(self):
+        data = bytes(range(0, 55))
+        message = b'##' + b'\xab\xcd' + b'\x00\x00\x00\x37' + data
+
+        record = []
+        genfunc = self._record(record, 0xabcd, 55, 0xdeadbeef, 'dummy')
+        decoder = wire_codec_v1.decode_wire_v1_stream(genfunc, 0xdeadbeef, 'dummy')
+        decoder.send(None)
+
+        try:
+            decoder.send(message)
+        except StopIteration as e:
+            res = e.value
+        self.assertEqual(res, None)
+        self.assertEqual(len(record), 2)
+        self.assertEqual(record[0], data)
+        self.assertIsInstance(record[1], EOFError)
+
+    def test_decode_generated_range(self):
+        for data_len in range(1, 512):
+            data = random.bytes(data_len)
+            data_chunks = [data[:55]] + list(chunks(data[55:], 63))
+
+            msg_type = 0xabcd
+            header = b'##' + ustruct.pack('>H', msg_type) + ustruct.pack('>L', data_len)
+
+            message = header + data
+            message_chunks = [c + '\x00' * (63 - len(c)) for c in list(chunks(message, 63))]
+
+            record = []
+            genfunc = self._record(record, msg_type, data_len, 0xdeadbeef, 'dummy')
+            decoder = wire_codec_v1.decode_wire_v1_stream(genfunc, 0xdeadbeef, 'dummy')
+            decoder.send(None)
+
+            res = 1
+            try:
+                for c in message_chunks:
+                    decoder.send(c)
+            except StopIteration as e:
+                res = e.value
+            self.assertEqual(res, None)
+            self.assertEqual(len(record), len(data_chunks) + 1)
+            for i in range(0, len(data_chunks)):
+                self.assertEqual(record[i], data_chunks[i])
+            self.assertIsInstance(record[-1], EOFError)
+
+    def test_encode_empty(self):
+        record = []
+        target = self._record(record)()
+        target.send(None)
+
+        wire_codec_v1.encode_wire_v1_message(0xabcd, b'', target)
+        self.assertEqual(len(record), 1)
+        self.assertEqual(record[0], b'?##\xab\xcd\x00\x00\x00\x00' + '\0' * 55)
+
+    def test_encode_one_report_aligned(self):
+        data = bytes(range(0, 55))
+
+        record = []
+        target = self._record(record)()
+        target.send(None)
+
+        wire_codec_v1.encode_wire_v1_message(0xabcd, data, target)
+        self.assertEqual(record, [b'?##\xab\xcd\x00\x00\x00\x37' + data])
+
+    def test_encode_generated_range(self):
+        for data_len in range(1, 1024):
+            data = random.bytes(data_len)
+
+            msg_type = 0xabcd
+            header = b'##' + ustruct.pack('>H', msg_type) + ustruct.pack('>L', data_len)
+
+            message = header + data
+            reports = [b'?' + c for c in chunks(message, 63)]
+            reports[-1] = reports[-1] + b'\x00' * (64 - len(reports[-1]))
+
+            received = 0
+            def genfunc():
+                nonlocal received
+                while True:
+                    self.assertEqual((yield), reports[received])
+                    received += 1
+            target = genfunc()
+            target.send(None)
+
+            wire_codec_v1.encode_wire_v1_message(msg_type, data, target)
+            self.assertEqual(received, len(reports))
+
+    def _record(self, record, *_args):
+        def genfunc(*args):
+            self.assertEqual(args, _args)
+            while True:
+                try:
+                    v = yield
+                except Exception as e:
+                    record.append(e)
+                else:
+                    record.append(v)
+        return genfunc
+
+
+if __name__ == '__main__':
+    unittest.main()

src/trezor/wire/wire_codec.py

@@ -84,10 +84,11 @@ class MessageChecksumError(Exception):
 def decode_wire_stream(genfunc, session_id, *args):
     '''Decode a wire message from the report data and stream it to target.
 
-Receives report payloads.
-Sends (msg_type, data_len) to target, followed by data chunks.
-Throws EOFError after last data chunk, in case of valid checksum.
-Throws MessageChecksumError to target if data doesn't match the checksum.
+Receives report payloads.  After first report, creates target by calling
+`genfunc(msg_type, data_len, session_id, *args)` and sends chunks of message
+data.
+Throws `EOFError` to target after last data chunk, in case of valid checksum.
+Throws `MessageChecksumError` to target if data doesn't match the checksum.
 
 Pass report payloads as `memoryview` for cheaper slicing.
 '''

src/trezor/wire/wire_codec_v1.py

@@ -2,7 +2,7 @@ from micropython import const
 import ustruct
 
 SESSION_V1 = const(0)
-REP_MARKER_V1 = const(63)  # ord('?)
+REP_MARKER_V1 = const(63)  # ord('?')
 REP_MARKER_V1_LEN = const(1)  # len('?')
 
 _REP_LEN = const(64)
@@ -16,18 +16,23 @@ def detect_v1(data):
 
 
 def parse_report_v1(data):
+    if len(data) != _REP_LEN:
+        raise ValueError('Invalid buffer size')
     return None, SESSION_V1, data[1:]
 
 
 def parse_message(data):
     magic1, magic2, msg_type, data_len = ustruct.unpack(_MSG_HEADER_V1, data)
     if magic1 != _MSG_HEADER_MAGIC or magic2 != _MSG_HEADER_MAGIC:
-        raise Exception('Corrupted magic bytes')
-
+        raise ValueError('Corrupted magic bytes')
     return msg_type, data_len, data[_MSG_HEADER_V1_LEN:]
 
 
 def serialize_message_header(data, msg_type, msg_len):
+    if len(data) < REP_MARKER_V1_LEN + _MSG_HEADER_V1_LEN:
+        raise ValueError('Invalid buffer size')
+    if msg_type < 0 or msg_type > 65535:
+        raise ValueError('Value is out of range')
     ustruct.pack_into(
         _MSG_HEADER_V1, data, REP_MARKER_V1_LEN,
         _MSG_HEADER_MAGIC, _MSG_HEADER_MAGIC, msg_type, msg_len)
@@ -36,10 +41,10 @@ def serialize_message_header(data, msg_type, msg_len):
 def decode_wire_v1_stream(genfunc, session_id, *args):
     '''Decode a v1 wire message from the report data and stream it to target.
 
-Receives report payloads.
-Sends (msg_type, data_len) to target, followed by data chunks.
-Throws EOFError after last data chunk, in case of valid checksum.
-Throws MessageChecksumError to target if data doesn't match the checksum.
+Receives report payloads.  After first report, creates target by calling
+`genfunc(msg_type, data_len, session_id, *args)` and sends chunks of message
+data.
+Throws `EOFError` to target after last data chunk.
 
 Pass report payloads as `memoryview` for cheaper slicing.
 '''
@@ -47,7 +52,6 @@ Pass report payloads as `memoryview` for cheaper slicing.
     message = yield  # read first report
     msg_type, data_len, data = parse_message(message)
 
-    print(msg_type, data_len, bytes(data))
     target = genfunc(msg_type, data_len, session_id, *args)
     target.send(None)
 
@@ -65,6 +69,11 @@ Pass report payloads as `memoryview` for cheaper slicing.
 
 
 def encode_wire_v1_message(msg_type, msg_data, target):
+    '''Encode a full v1 wire message directly to reports and stream it to target.
+
+Target receives `memoryview`s of HID reports which are valid until the targets
+`send()` method returns.
+    '''
     report = memoryview(bytearray(_REP_LEN))
     report[0] = REP_MARKER_V1
     serialize_message_header(report, msg_type, len(msg_data))
@@ -79,7 +88,7 @@ def encode_wire_v1_message(msg_type, msg_data, target):
         source_data = source_data[n:]
         target_data = target_data[n:]
 
-        # FIXME: optimize speed
+        # fill the rest of the report with 0x00
         x = 0
         to_fill = len(target_data)
         while x < to_fill: