AU: Verify delta payload signature and signed hash.

SConstruct

 # Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
 
 # Protobuffer compilation
 def ProtocolBufferEmitter(target, source, env):
   """ Inputs:
           target: list of targets to compile to
@@ skipping 101 matching lines @@
     cmd = '/usr/bin/glib-genmarshal %s --prefix=update_engine ' \
           '%s > %s' % (mode_flag, str(source[0]), str(target_file))
     commands.append(cmd)
   return commands
 
 glib_marshal_builder = Builder(generator = GlibMarshalGenerator,
                                emitter = GlibMarshalEmitter,
                                single_source = 1,
                                suffix = 'glibmarshal.c')
 
+# Public key generation
+def PublicKeyEmitter(target, source, env):
+  """ Inputs:
+          target: list of targets to compile to
+          source: list of sources to compile
+          env: the scons environment in which we are compiling
+      Outputs:
+          target: the list of targets we'll emit
+          source: the list of sources we'll compile"""
+  targets = []
+  for source_file in source:
+    output = str(source_file)
+    output = output[0:output.rfind('.pem')]
+    output += '.pub.pem'
+    targets.append(output)
+  return targets, source
+
+def PublicKeyGenerator(source, target, env, for_signature):
+  """ Inputs:
+          source: list of sources to process
+          target: list of targets to generate
+          env: scons environment in which we are working
+          for_signature: unused
+      Outputs: a list of commands to execute to generate the targets from
+               the sources."""
+  commands = []
+  for source_file in source:
+    output = str(source_file)
+    output = output[0:output.rfind('.pem')]
+    output += '.pub.pem'
+    cmd = '/usr/bin/openssl rsa -in %s -pubout -out %s' % (source_file, output)
+    commands.append(cmd)
+  return commands
+
+public_key_builder = Builder(generator = PublicKeyGenerator,
+                             emitter = PublicKeyEmitter,
+                             suffix = '.pub.pem')
+
 env = Environment()
 for key in Split('CC CXX AR RANLIB LD NM'):
   value = os.environ.get(key)
   if value != None:
     env[key] = value
 for key in Split('CFLAGS CCFLAGS CPPPATH LIBPATH'):
   value = os.environ.get(key)
   if value != None:
     env[key] = Split(value)
 
@@ skipping 35 matching lines @@
                        protobuf
                        pthread
                        rootdev
                        ssl
                        xml2
                        z""")
 env['CPPPATH'] = ['..']
 env['BUILDERS']['ProtocolBuffer'] = proto_builder
 env['BUILDERS']['DbusBindings'] = dbus_bindings_builder
 env['BUILDERS']['GlibMarshal'] = glib_marshal_builder
+env['BUILDERS']['PublicKey'] = public_key_builder
 
 # Fix issue with scons not passing pkg-config vars through the environment.
 for key in Split('PKG_CONFIG_LIBDIR PKG_CONFIG_PATH'):
   if os.environ.has_key(key):
     env['ENV'][key] = os.environ[key]
 
 env.ParseConfig('pkg-config --cflags --libs '
                 'dbus-1 dbus-glib-1 gio-2.0 gio-unix-2.0 glib-2.0')
 env.ProtocolBuffer('update_metadata.pb.cc', 'update_metadata.proto')
+env.PublicKey('unittest_key.pub.pem', 'unittest_key.pem')
 
 env.DbusBindings('update_engine.dbusclient.h', 'update_engine.xml')
 
 env.GlibMarshal('marshal.glibmarshal.c', 'marshal.list')
 
 if ARGUMENTS.get('debug', 0):
   env['CCFLAGS'] += ' -fprofile-arcs -ftest-coverage'
   env['LIBS'] += ['bz2', 'gcov']
 
 sources = Split("""action_processor.cc
@@ skipping 80 matching lines @@
 # of generating other files (usually their corresponding .c(c) files),
 # so we make all sources depend on those other files.
 all_sources = []
 all_sources.extend(sources)
 all_sources.extend(unittest_sources)
 all_sources.extend(main)
 all_sources.extend(unittest_main)
 all_sources.extend(client_main)
 all_sources.extend(delta_generator_main)
 for source in all_sources:
+  if source.endswith('_unittest.cc'):
+    env.Depends(source, 'unittest_key.pub.pem')
   if source.endswith('.glibmarshal.c') or source.endswith('.pb.cc'):
     continue
   env.Depends(source, 'update_metadata.pb.cc')
   env.Depends(source, 'marshal.glibmarshal.c')
   env.Depends(source, 'update_engine.dbusclient.h')
 
 update_engine_core = env.Library('update_engine_core', sources)
 env.Prepend(LIBS=[update_engine_core])
 
 env.Program('update_engine', main)
 
 client_cmd = env.Program('update_engine_client', client_main);
 
 delta_generator_cmd = env.Program('delta_generator',
                                   delta_generator_main)
 
 http_server_cmd = env.Program('test_http_server', 'test_http_server.cc')
 
 unittest_env = env.Clone()
 unittest_env.Append(LIBS=['gmock', 'gtest'])
 unittest_cmd = unittest_env.Program('update_engine_unittests',
                            unittest_sources + unittest_main)
 Clean(unittest_cmd, Glob('*.gcda') + Glob('*.gcno') + Glob('*.gcov') +
                     Split('html app.info'))