paycheck: Improve minor_version checking.

1) We explicitly catch whether this field is not set. This means we
   might fail payloads generated by an old delta_generator, but ensures
   that we catch such a failure in current payload generation.  Test
   logic slightly restructured to reduce duplication.

2) Slight changes to the checker method signature, for better uniformity
   with the rest of the code. This also lets us test that we actually
   read the minor_version field.

BUG=chromium:508566
TEST=Unit tests (revised)

Change-Id: Ib2d1999964ba892ef778ffc16bd1ca1c7d02bcd5
Reviewed-on: https://chromium-review.googlesource.com/285446
Tested-by: Gilad Arnold <garnold@chromium.org>
Reviewed-by: Gilad Arnold <garnold@chromium.org>
Commit-Queue: Gilad Arnold <garnold@chromium.org>

1 files changed, 26 insertions, 26 deletions

diff --git a/scripts/update_payload/checker.py b/scripts/update_payload/checker.py
index f2aa7bbf..5428f66e 100644
--- a/scripts/update_payload/checker.py
+++ b/scripts/update_payload/checker.py
@@ -50,6 +50,12 @@ _DEFAULT_PUBKEY_BASE_NAME = 'update-payload-key.pub.pem'
 _DEFAULT_PUBKEY_FILE_NAME = os.path.join(os.path.dirname(__file__),
                                          _DEFAULT_PUBKEY_BASE_NAME)
 
+# Supported minor version map to payload types allowed to be using them.
+_SUPPORTED_MINOR_VERSIONS = {
+    0: (_TYPE_FULL,),
+    1: (_TYPE_DELTA,),
+    2: (_TYPE_DELTA,),
+}
 
 #
 # Helper functions.
@@ -311,6 +317,7 @@ class PayloadChecker(object):
     self.old_kernel_fs_size = 0
     self.new_rootfs_fs_size = 0
     self.new_kernel_fs_size = 0
+    self.minor_version = None
 
   @staticmethod
   def _CheckElem(msg, name, report, is_mandatory, is_submsg, convert=str,
@@ -494,33 +501,27 @@ class PayloadChecker(object):
           '%s (%d) <= (num %sblocks - 1 (%d)) * block_size (%d).' %
           (length_name, length, block_name or '', num_blocks - 1, block_size))
 
-  def _CheckMinorVersion(self, report, minor_version, payload_type):
-    """Checks that the minor version matches the payload type.
+  def _CheckManifestMinorVersion(self, report):
+    """Checks the payload manifest minor_version field.
 
     Args:
       report: The report object to add to.
-      minor_version: The minor version of the payload.
-      payload_type: The type of payload (full or delta).
 
     Raises:
-      error.PayloadError if any of the checks fails.
+      error.PayloadError if any of the checks fail.
     """
-    report.AddField('minor version', minor_version)
-
-    if minor_version == 0:
-      # Minor version 0 implies a full payload.
-      if payload_type != _TYPE_FULL:
-        raise error.PayloadError(
-            'Minor version 0 not compatible with payload type: %s.'
-            % payload_type)
-    elif minor_version in (1, 2):
-      # Minor version 1 or 2 implies a delta payload.
-      if payload_type != _TYPE_DELTA:
+    self.minor_version = self._CheckOptionalField(self.payload.manifest,
+                                                  'minor_version', report)
+    if self.minor_version in _SUPPORTED_MINOR_VERSIONS:
+      if self.payload_type not in _SUPPORTED_MINOR_VERSIONS[self.minor_version]:
         raise error.PayloadError(
-            'Minor version %d not compatible with payload type: %s.'
-            % (minor_version, payload_type))
+            'Minor version %d not compatible with payload type %s.' %
+            (self.minor_version, self.payload_type))
+    elif self.minor_version is None:
+      raise error.PayloadError('Minor version is not set.')
     else:
-      raise error.PayloadError('Unsupported minor version: %d' % minor_version)
+      raise error.PayloadError('Unsupported minor version: %d' %
+                               self.minor_version)
 
   def _CheckManifest(self, report, rootfs_part_size=0, kernel_part_size=0):
     """Checks the payload manifest.
@@ -623,7 +624,7 @@ class PayloadChecker(object):
 
     # Check: minor_version makes sense for the payload type. This check should
     # run after the payload type has been set.
-    self._CheckMinorVersion(report, manifest.minor_version, self.payload_type)
+    self._CheckManifestMinorVersion(report)
 
   def _CheckLength(self, length, total_blocks, op_name, length_name):
     """Checks whether a length matches the space designated in extents.
@@ -943,23 +944,22 @@ class PayloadChecker(object):
             (op_name, data_offset, prev_data_offset))
 
     # Type-specific checks.
-    minor_version = self.payload.manifest.minor_version
     if op.type in (common.OpType.REPLACE, common.OpType.REPLACE_BZ):
       self._CheckReplaceOperation(op, data_length, total_dst_blocks, op_name)
-    elif op.type == common.OpType.MOVE and minor_version == 1:
+    elif op.type == common.OpType.MOVE and self.minor_version == 1:
       self._CheckMoveOperation(op, data_offset, total_src_blocks,
                                total_dst_blocks, op_name)
-    elif op.type == common.OpType.BSDIFF and minor_version == 1:
+    elif op.type == common.OpType.BSDIFF and self.minor_version == 1:
       self._CheckBsdiffOperation(data_length, total_dst_blocks, op_name)
-    elif op.type == common.OpType.SOURCE_COPY and minor_version == 2:
+    elif op.type == common.OpType.SOURCE_COPY and self.minor_version == 2:
       self._CheckSourceCopyOperation(data_offset, total_src_blocks,
                                      total_dst_blocks, op_name)
-    elif op.type == common.OpType.SOURCE_BSDIFF and minor_version == 2:
+    elif op.type == common.OpType.SOURCE_BSDIFF and self.minor_version == 2:
       self._CheckBsdiffOperation(data_length, total_dst_blocks, op_name)
     else:
       raise error.PayloadError(
           'Operation %s (type %d) not allowed in minor version %d' %
-          (op_name, op.type, minor_version))
+          (op_name, op.type, self.minor_version))
     return data_length if data_length is not None else 0
 
   def _SizeToNumBlocks(self, size):