Add fuzzing programming cycle tests

test/test_fuzzing.py

@@ -0,0 +1,119 @@
+#
+# Copyright (c) 2017 Grigori Goronzy <greg@chown.ath.cx>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+#
+
+"""Tests with fuzzing of input data"""
+
+import random
+import sys
+import unittest
+from unittest.mock import patch
+import yaml
+import stcgal.frontend
+import stcgal.protocols
+from test.test_program import get_default_opts, convert_to_bytes
+
+class ByteArrayFuzzer:
+    """Fuzzer for byte arrays"""
+
+    def __init__(self):
+        self.rng = random.Random()
+        self.cut_propability = 0.01 # probability for cutting off an array early
+        self.cut_min = 0 # minimum cut amount
+        self.cut_max = sys.maxsize # maximum cut amount
+        self.bitflip_probability = 0.0001 # probability for flipping a bit
+        self.randomize_probability = 0.001 # probability for randomizing a char
+
+    def fuzz(self, inp):
+        """Fuzz an array of bytes according to predefined settings"""
+        arr = bytearray(inp)
+        arr = self.cut_off(arr)
+        self.randomize(arr)
+        return bytes(arr)
+
+    def randomize(self, arr):
+        """Randomize array contents with bitflips and random bytes"""
+        for i, _ in enumerate(arr):
+            for j in range(8):
+                if self.rng.random() < self.bitflip_probability:
+                    arr[i] ^= (1 << j)
+            if self.rng.random() < self.randomize_probability:
+                arr[i] = self.rng.getrandbits(8)
+
+    def cut_off(self, arr):
+        """Cut off data from end of array"""
+        if self.rng.random() < self.cut_propability:
+            cut_limit = min(len(arr), self.cut_max)
+            cut_len = self.rng.randrange(self.cut_min, cut_limit)
+            arr = arr[0:len(arr) - cut_len]
+        return arr
+
+class TestProgramFuzzed(unittest.TestCase):
+    """Special programming cycle tests that use a fuzzing approach"""
+
+    @patch("stcgal.protocols.StcBaseProtocol.read_packet")
+    @patch("stcgal.protocols.Stc89Protocol.write_packet")
+    @patch("stcgal.protocols.serial.Serial", autospec=True)
+    @patch("stcgal.protocols.time.sleep")
+    @patch("sys.stdout")
+    @patch("sys.stderr")
+    def test_program_fuzz(self, err, out, sleep_mock, serial_mock, write_mock, read_mock):
+        """Test programming cycles with fuzzing enabled"""
+        yml = [
+            "./test/iap15f2k61s2.yml",
+            "./test/stc12c2052ad.yml",
+            "./test/stc15w4k56s4.yml",
+            "./test/stc12c5a60s2.yml",
+            "./test/stc89c52rc.yml",
+            "./test/stc15l104w.yml",
+            "./test/stc15f104e.yml",
+        ]
+        fuzzer = ByteArrayFuzzer()
+        fuzzer.cut_propability = 0.01
+        fuzzer.bitflip_probability = 0.005
+        fuzzer.rng = random.Random(1)
+        for y in yml:
+            with self.subTest(msg="trace {}".format(y)):
+                self.single_fuzz(y, serial_mock, fuzzer, read_mock, err, out,
+                                 sleep_mock, write_mock)
+
+    def single_fuzz(self, yml, serial_mock, fuzzer, read_mock, err, out, sleep_mock, write_mock):
+        """Test a single programming cycle with fuzzing"""
+        with open(yml) as test_file:
+            test_data = yaml.load(test_file.read())
+            for _ in range(1000):
+                with self.subTest():
+                    opts = get_default_opts()
+                    opts.protocol = test_data["protocol"]
+                    opts.code_image.read.return_value = bytes(test_data["code_data"])
+                    serial_mock.return_value.inWaiting.return_value = 1
+                    fuzzed_responses = []
+                    for arr in convert_to_bytes(test_data["responses"]):
+                        fuzzed_responses.append(fuzzer.fuzz(arr))
+                    read_mock.side_effect = fuzzed_responses
+                    gal = stcgal.frontend.StcGal(opts)
+                    self.assertGreaterEqual(gal.run(), 0)
+                    err.reset_mock()
+                    out.reset_mock()
+                    sleep_mock.reset_mock()
+                    serial_mock.reset_mock()
+                    write_mock.reset_mock()
+                    read_mock.reset_mock()