releasetools: Make verity_utils Python 3 compatible.

Bug: 131631303
Test: TreeHugger
Test: `python -m unittest test_verity_utils`
Test: `python3 -m unittest test_verity_utils`
Change-Id: Idc7776be2cf78fbdb0b3ba87231d05013da8d3ac

tools/releasetools/test_verity_utils.py

@@ -47,25 +47,22 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
     }
 
     self.hash_algorithm = "sha256"
-    self.fixed_salt = \
-        "aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7"
-    self.expected_root_hash = \
-        "0b7c4565e87b1026e11fbab91c0bc29e185c847a5b44d40e6e86e461e8adf80d"
+    self.fixed_salt = (
+        "aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7")
+    self.expected_root_hash = (
+        "0b7c4565e87b1026e11fbab91c0bc29e185c847a5b44d40e6e86e461e8adf80d")
 
-  def _create_simg(self, raw_data):
+  def _CreateSimg(self, raw_data):  # pylint: disable=no-self-use
     output_file = common.MakeTempFile()
     raw_image = common.MakeTempFile()
     with open(raw_image, 'wb') as f:
       f.write(raw_data)
 
     cmd = ["img2simg", raw_image, output_file, '4096']
-    p = common.Run(cmd)
-    p.communicate()
-    self.assertEqual(0, p.returncode)
-
+    common.RunAndCheckOutput(cmd)
     return output_file
 
-  def _generate_image(self):
+  def _GenerateImage(self):
     partition_size = 1024 * 1024
     prop_dict = {
         'partition_size': str(partition_size),
@@ -79,11 +76,11 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
     self.assertIsNotNone(verity_image_builder)
     adjusted_size = verity_image_builder.CalculateMaxImageSize()
 
-    raw_image = ""
+    raw_image = bytearray(adjusted_size)
     for i in range(adjusted_size):
-      raw_image += str(i % 10)
+      raw_image[i] = ord('0') + i % 10
 
-    output_file = self._create_simg(raw_image)
+    output_file = self._CreateSimg(raw_image)
 
     # Append the verity metadata.
     verity_image_builder.Build(output_file)
@@ -92,7 +89,7 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
 
   @SkipIfExternalToolsUnavailable()
   def test_CreateHashtreeInfoGenerator(self):
-    image_file = sparse_img.SparseImage(self._generate_image())
+    image_file = sparse_img.SparseImage(self._GenerateImage())
 
     generator = CreateHashtreeInfoGenerator(
         'system', image_file, self.prop_dict)
@@ -103,7 +100,7 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
 
   @SkipIfExternalToolsUnavailable()
   def test_DecomposeSparseImage(self):
-    image_file = sparse_img.SparseImage(self._generate_image())
+    image_file = sparse_img.SparseImage(self._GenerateImage())
 
     generator = VerifiedBootVersion1HashtreeInfoGenerator(
         self.partition_size, 4096, True)
@@ -114,7 +111,7 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
 
   @SkipIfExternalToolsUnavailable()
   def test_ParseHashtreeMetadata(self):
-    image_file = sparse_img.SparseImage(self._generate_image())
+    image_file = sparse_img.SparseImage(self._GenerateImage())
     generator = VerifiedBootVersion1HashtreeInfoGenerator(
         self.partition_size, 4096, True)
     generator.DecomposeSparseImage(image_file)
@@ -131,12 +128,12 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
   def test_ValidateHashtree_smoke(self):
     generator = VerifiedBootVersion1HashtreeInfoGenerator(
         self.partition_size, 4096, True)
-    generator.image = sparse_img.SparseImage(self._generate_image())
+    generator.image = sparse_img.SparseImage(self._GenerateImage())
 
     generator.hashtree_info = info = HashtreeInfo()
-    info.filesystem_range = RangeSet(data=[0, 991232 / 4096])
+    info.filesystem_range = RangeSet(data=[0, 991232 // 4096])
     info.hashtree_range = RangeSet(
-        data=[991232 / 4096, (991232 + 12288) / 4096])
+        data=[991232 // 4096, (991232 + 12288) // 4096])
     info.hash_algorithm = self.hash_algorithm
     info.salt = self.fixed_salt
     info.root_hash = self.expected_root_hash
@@ -147,12 +144,12 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
   def test_ValidateHashtree_failure(self):
     generator = VerifiedBootVersion1HashtreeInfoGenerator(
         self.partition_size, 4096, True)
-    generator.image = sparse_img.SparseImage(self._generate_image())
+    generator.image = sparse_img.SparseImage(self._GenerateImage())
 
     generator.hashtree_info = info = HashtreeInfo()
-    info.filesystem_range = RangeSet(data=[0, 991232 / 4096])
+    info.filesystem_range = RangeSet(data=[0, 991232 // 4096])
     info.hashtree_range = RangeSet(
-        data=[991232 / 4096, (991232 + 12288) / 4096])
+        data=[991232 // 4096, (991232 + 12288) // 4096])
     info.hash_algorithm = self.hash_algorithm
     info.salt = self.fixed_salt
     info.root_hash = "a" + self.expected_root_hash[1:]
@@ -161,12 +158,12 @@ class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
 
   @SkipIfExternalToolsUnavailable()
   def test_Generate(self):
-    image_file = sparse_img.SparseImage(self._generate_image())
+    image_file = sparse_img.SparseImage(self._GenerateImage())
     generator = CreateHashtreeInfoGenerator('system', 4096, self.prop_dict)
     info = generator.Generate(image_file)
 
-    self.assertEqual(RangeSet(data=[0, 991232 / 4096]), info.filesystem_range)
-    self.assertEqual(RangeSet(data=[991232 / 4096, (991232 + 12288) / 4096]),
+    self.assertEqual(RangeSet(data=[0, 991232 // 4096]), info.filesystem_range)
+    self.assertEqual(RangeSet(data=[991232 // 4096, (991232 + 12288) // 4096]),
                      info.hashtree_range)
     self.assertEqual(self.hash_algorithm, info.hash_algorithm)
     self.assertEqual(self.fixed_salt, info.salt)

tools/releasetools/verity_utils.py

@@ -131,7 +131,8 @@ def Append(target, file_to_append, error_message):
     BuildVerityImageError: On error.
   """
   try:
-    with open(target, "a") as out_file, open(file_to_append, "r") as input_file:
+    with open(target, 'ab') as out_file, \
+        open(file_to_append, 'rb') as input_file:
       for line in input_file:
         out_file.write(line)
   except IOError:
@@ -178,6 +179,8 @@ def CreateVerityImageBuilder(prop_dict):
     # key_path and algorithm are only available when chain partition is used.
     key_path = prop_dict.get("avb_key_path")
     algorithm = prop_dict.get("avb_algorithm")
+
+    # Image uses hash footer.
     if prop_dict.get("avb_hash_enable") == "true":
       return VerifiedBootVersion2VerityImageBuilder(
           prop_dict["partition_name"],
@@ -188,16 +191,17 @@ def CreateVerityImageBuilder(prop_dict):
           algorithm,
           prop_dict.get("avb_salt"),
           prop_dict["avb_add_hash_footer_args"])
-    else:
-      return VerifiedBootVersion2VerityImageBuilder(
-          prop_dict["partition_name"],
-          partition_size,
-          VerifiedBootVersion2VerityImageBuilder.AVB_HASHTREE_FOOTER,
-          prop_dict["avb_avbtool"],
-          key_path,
-          algorithm,
-          prop_dict.get("avb_salt"),
-          prop_dict["avb_add_hashtree_footer_args"])
+
+    # Image uses hashtree footer.
+    return VerifiedBootVersion2VerityImageBuilder(
+        prop_dict["partition_name"],
+        partition_size,
+        VerifiedBootVersion2VerityImageBuilder.AVB_HASHTREE_FOOTER,
+        prop_dict["avb_avbtool"],
+        key_path,
+        algorithm,
+        prop_dict.get("avb_salt"),
+        prop_dict["avb_add_hashtree_footer_args"])
 
   return None
 
@@ -605,19 +609,19 @@ class VerifiedBootVersion1HashtreeInfoGenerator(HashtreeInfoGenerator):
     self.metadata_size = metadata_size
 
     self.hashtree_info.filesystem_range = RangeSet(
-        data=[0, adjusted_size / self.block_size])
+        data=[0, adjusted_size // self.block_size])
     self.hashtree_info.hashtree_range = RangeSet(
-        data=[adjusted_size / self.block_size,
-              (adjusted_size + verity_tree_size) / self.block_size])
+        data=[adjusted_size // self.block_size,
+              (adjusted_size + verity_tree_size) // self.block_size])
 
   def _ParseHashtreeMetadata(self):
     """Parses the hash_algorithm, root_hash, salt from the metadata block."""
 
     metadata_start = self.filesystem_size + self.hashtree_size
     metadata_range = RangeSet(
-        data=[metadata_start / self.block_size,
-              (metadata_start + self.metadata_size) / self.block_size])
-    meta_data = ''.join(self.image.ReadRangeSet(metadata_range))
+        data=[metadata_start // self.block_size,
+              (metadata_start + self.metadata_size) // self.block_size])
+    meta_data = b''.join(self.image.ReadRangeSet(metadata_range))
 
     # More info about the metadata structure available in:
     # system/extras/verity/build_verity_metadata.py
@@ -640,9 +644,9 @@ class VerifiedBootVersion1HashtreeInfoGenerator(HashtreeInfoGenerator):
     assert (int(table_entries[5]) * self.block_size == self.filesystem_size and
             int(table_entries[6]) * self.block_size == self.filesystem_size)
 
-    self.hashtree_info.hash_algorithm = table_entries[7]
-    self.hashtree_info.root_hash = table_entries[8]
-    self.hashtree_info.salt = table_entries[9]
+    self.hashtree_info.hash_algorithm = table_entries[7].decode()
+    self.hashtree_info.root_hash = table_entries[8].decode()
+    self.hashtree_info.salt = table_entries[9].decode()
 
   def ValidateHashtree(self):
     """Checks that we can reconstruct the verity hash tree."""
@@ -669,8 +673,8 @@ class VerifiedBootVersion1HashtreeInfoGenerator(HashtreeInfoGenerator):
 
     # Reads the generated hash tree and checks if it has the exact same bytes
     # as the one in the sparse image.
-    with open(generated_verity_tree, "rb") as fd:
-      return fd.read() == ''.join(self.image.ReadRangeSet(
+    with open(generated_verity_tree, 'rb') as fd:
+      return fd.read() == b''.join(self.image.ReadRangeSet(
           self.hashtree_info.hashtree_range))
 
   def Generate(self, image):