Using a python script to build sepolicy
Current sepolicy CIL files are built by several command-line tools
in Android.mk. This change extracts some of the build logic into a
python script to relief the effort in Android.mk.
The first command is `build_sepolicy build_cil`. It's possible to add
more sub-commands under the build_sepolicy script in the future.
Bug: 64240127
Test: build bullhead/taimen
Change-Id: Ie0ae4fc5256a550c72954cde5d5dd213a22d159a
diff --git a/Android.bp b/Android.bp
index 9952a8f..1785342 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1 +1,4 @@
-subdirs = ["tests"]
+subdirs = [
+ "tests",
+ "build",
+]
diff --git a/Android.mk b/Android.mk
index 40c4570..759efe1 100644
--- a/Android.mk
+++ b/Android.mk
@@ -228,11 +228,14 @@
LOCAL_REQUIRED_MODULES += precompiled_sepolicy precompiled_sepolicy.plat_and_mapping.sha256
endif
else
-# Use monolithic SELinux policy
-LOCAL_REQUIRED_MODULES += sepolicy
+# The following files are only allowed for non-Treble devices.
+LOCAL_REQUIRED_MODULES += \
+ sepolicy \
+ vendor_service_contexts
endif
LOCAL_REQUIRED_MODULES += \
+ build_sepolicy \
vendor_file_contexts \
vendor_mac_permissions.xml \
vendor_property_contexts \
@@ -247,10 +250,6 @@
searchpolicy \
vndservice_contexts \
-ifneq ($(PRODUCT_SEPOLICY_SPLIT),true)
-LOCAL_REQUIRED_MODULES += vendor_service_contexts
-endif
-
ifneq ($(TARGET_BUILD_VARIANT), user)
LOCAL_REQUIRED_MODULES += \
selinux_denial_metadata \
@@ -540,31 +539,23 @@
$(transform-policy-to-conf)
$(hide) sed '/dontaudit/d' $@ > $@.dontaudit
-vendor_policy_raw := $(intermediates)/vendor_policy_raw.cil
-$(vendor_policy_raw): PRIVATE_POL_CONF := $(vendor_policy.conf)
-$(vendor_policy_raw): PRIVATE_REQD_MASK := $(reqd_policy_mask.cil)
-$(vendor_policy_raw): $(HOST_OUT_EXECUTABLES)/checkpolicy $(vendor_policy.conf) \
-$(reqd_policy_mask.cil)
- @mkdir -p $(dir $@)
- $(hide) $(CHECKPOLICY_ASAN_OPTIONS) $< -C -M -c $(POLICYVERS) -o $@.tmp $(PRIVATE_POL_CONF)
- $(hide) grep -Fxv -f $(PRIVATE_REQD_MASK) $@.tmp > $@
-
-$(LOCAL_BUILT_MODULE) : PRIVATE_VERS := $(BOARD_SEPOLICY_VERS)
-$(LOCAL_BUILT_MODULE) : PRIVATE_TGT_POL := $(vendor_policy_raw)
-$(LOCAL_BUILT_MODULE) : PRIVATE_DEP_CIL_FILES := $(built_plat_cil) $(built_plat_pub_vers_cil) $(built_mapping_cil)
-$(LOCAL_BUILT_MODULE) : PRIVATE_FILTER_CIL := $(built_plat_pub_vers_cil)
-$(LOCAL_BUILT_MODULE) : $(plat_pub_policy.cil) $(vendor_policy_raw) \
- $(HOST_OUT_EXECUTABLES)/version_policy $(HOST_OUT_EXECUTABLES)/secilc \
+$(LOCAL_BUILT_MODULE): PRIVATE_POL_CONF := $(vendor_policy.conf)
+$(LOCAL_BUILT_MODULE): PRIVATE_REQD_MASK := $(reqd_policy_mask.cil)
+$(LOCAL_BUILT_MODULE): PRIVATE_BASE_CIL := $(plat_pub_policy.cil)
+$(LOCAL_BUILT_MODULE): PRIVATE_VERS := $(BOARD_SEPOLICY_VERS)
+$(LOCAL_BUILT_MODULE): PRIVATE_DEP_CIL_FILES := $(built_plat_cil) $(built_plat_pub_vers_cil) $(built_mapping_cil)
+$(LOCAL_BUILT_MODULE): PRIVATE_FILTER_CIL := $(built_plat_pub_vers_cil)
+$(LOCAL_BUILT_MODULE): $(HOST_OUT_EXECUTABLES)/build_sepolicy \
+ $(vendor_policy.conf) $(reqd_policy_mask.cil) $(plat_pub_policy.cil) \
$(built_plat_cil) $(built_plat_pub_vers_cil) $(built_mapping_cil)
@mkdir -p $(dir $@)
- $(HOST_OUT_EXECUTABLES)/version_policy -b $< -t $(PRIVATE_TGT_POL) -n $(PRIVATE_VERS) -o $@.tmp
- $(hide) grep -Fxv -f $(PRIVATE_FILTER_CIL) $@.tmp > $@
- $(hide) $(HOST_OUT_EXECUTABLES)/secilc -m -M true -G -N -c $(POLICYVERS) \
- $(PRIVATE_DEP_CIL_FILES) $@ -o /dev/null -f /dev/null
+ $(hide) $(HOST_OUT_EXECUTABLES)/build_sepolicy -a $(HOST_OUT_EXECUTABLES) build_cil \
+ -i $(PRIVATE_POL_CONF) -m $(PRIVATE_REQD_MASK) -c $(CHECKPOLICY_ASAN_OPTIONS) \
+ -b $(PRIVATE_BASE_CIL) -d $(PRIVATE_DEP_CIL_FILES) -f $(PRIVATE_FILTER_CIL) \
+ -t $(PRIVATE_VERS) -p $(POLICYVERS) -o $@
built_vendor_cil := $(LOCAL_BUILT_MODULE)
vendor_policy.conf :=
-vendor_policy_raw :=
#################################
include $(CLEAR_VARS)
diff --git a/build/Android.bp b/build/Android.bp
new file mode 100644
index 0000000..d3f1fc3
--- /dev/null
+++ b/build/Android.bp
@@ -0,0 +1,34 @@
+// Copyright (C) 2018 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+python_binary_host {
+ name: "build_sepolicy",
+ srcs: [
+ "build_sepolicy.py",
+ "file_utils.py",
+ ],
+ required: [
+ "checkpolicy",
+ "secilc",
+ "version_policy",
+ ],
+ version: {
+ py2: {
+ enabled: true,
+ },
+ py3: {
+ enabled: false,
+ },
+ },
+}
diff --git a/build/build_sepolicy.py b/build/build_sepolicy.py
new file mode 100644
index 0000000..ff2ff07
--- /dev/null
+++ b/build/build_sepolicy.py
@@ -0,0 +1,140 @@
+# Copyright 2018 - The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Command-line tool to build SEPolicy files."""
+
+import argparse
+import os
+import subprocess
+import sys
+
+import file_utils
+
+
+# All supported commands in this module.
+# For each command, need to add two functions. Take 'build_cil' for example:
+# - setup_build_cil()
+# - Sets up command parsers and sets default function to do_build_cil().
+# - do_build_cil()
+_SUPPORTED_COMMANDS = ('build_cil',)
+
+
+def run_host_command(args, **kwargs):
+ """Runs a host command and prints output."""
+ if kwargs.get('shell'):
+ command_log = args
+ else:
+ command_log = ' '.join(args) # For args as a sequence.
+
+ try:
+ subprocess.check_call(args, **kwargs)
+ except subprocess.CalledProcessError as err:
+ sys.stderr.write(
+ 'build_sepolicy - failed to run command: {!r} (ret:{})\n'.format(
+ command_log, err.returncode))
+ sys.exit(err.returncode)
+
+
+def do_build_cil(args):
+ """Builds a sepolicy CIL (Common Intermediate Language) file.
+
+ This functions invokes some host utils (e.g., secilc, checkpolicy,
+ version_sepolicy) to generate a .cil file.
+
+ Args:
+ args: the parsed command arguments.
+ """
+ # Determines the raw CIL file name.
+ input_file_name = os.path.splitext(args.input_policy_conf)[0]
+ raw_cil_file = input_file_name + '_raw.cil'
+ # Builds the raw CIL.
+ file_utils.make_parent_dirs(raw_cil_file)
+ checkpolicy_cmd = [args.checkpolicy_env]
+ checkpolicy_cmd += [os.path.join(args.android_host_path, 'checkpolicy'),
+ '-C', '-M', '-c', args.policy_vers,
+ '-o', raw_cil_file, args.input_policy_conf]
+ # Using shell=True to setup args.checkpolicy_env variables.
+ run_host_command(' '.join(checkpolicy_cmd), shell=True)
+ file_utils.filter_out([args.reqd_mask], raw_cil_file)
+
+ # Builds the output CIL by versioning the above raw CIL.
+ output_file = args.output_cil
+ if output_file is None:
+ output_file = input_file_name + '.cil'
+ file_utils.make_parent_dirs(output_file)
+
+ run_host_command([os.path.join(args.android_host_path, 'version_policy'),
+ '-b', args.base_policy, '-t', raw_cil_file,
+ '-n', args.treble_sepolicy_vers, '-o', output_file])
+ if args.filter_out_files:
+ file_utils.filter_out(args.filter_out_files, output_file)
+
+ # Tests that the output file can be merged with the given CILs.
+ if args.dependent_cils:
+ merge_cmd = [os.path.join(args.android_host_path, 'secilc'),
+ '-m', '-M', 'true', '-G', '-N', '-c', args.policy_vers]
+ merge_cmd += args.dependent_cils # the give CILs to merge
+ merge_cmd += [output_file, '-o', '/dev/null', '-f', '/dev/null']
+ run_host_command(merge_cmd)
+
+
+def setup_build_cil(subparsers):
+ """Sets up command args for 'build_cil' command."""
+
+ # Required arguments.
+ parser = subparsers.add_parser('build_cil', help='build CIL files')
+ parser.add_argument('-i', '--input_policy_conf', required=True,
+ help='source policy.conf')
+ parser.add_argument('-m', '--reqd_mask', required=True,
+ help='the bare minimum policy.conf to use checkpolicy')
+ parser.add_argument('-b', '--base_policy', required=True,
+ help='base policy for versioning')
+ parser.add_argument('-t', '--treble_sepolicy_vers', required=True,
+ help='the version number to use for Treble-OTA')
+ parser.add_argument('-p', '--policy_vers', required=True,
+ help='SELinux policy version')
+
+ # Optional arguments.
+ parser.add_argument('-c', '--checkpolicy_env',
+ help='environment variables passed to checkpolicy')
+ parser.add_argument('-f', '--filter_out_files', nargs='+',
+ help='the pattern files to filter out the output cil')
+ parser.add_argument('-d', '--dependent_cils', nargs='+',
+ help=('check the output file can be merged with '
+ 'the dependent cil files'))
+ parser.add_argument('-o', '--output_cil', help='the output cil file')
+
+ # The function that performs the actual works.
+ parser.set_defaults(func=do_build_cil)
+
+
+def run(argv):
+ """Sets up command parser and execuates sub-command."""
+ parser = argparse.ArgumentParser()
+
+ # Adds top-level arguments.
+ parser.add_argument('-a', '--android_host_path', default='',
+ help='a path to host out executables')
+
+ # Adds subparsers for each COMMAND.
+ subparsers = parser.add_subparsers(title='COMMAND')
+ for command in _SUPPORTED_COMMANDS:
+ globals()['setup_' + command](subparsers)
+
+ args = parser.parse_args(argv[1:])
+ args.func(args)
+
+
+if __name__ == '__main__':
+ run(sys.argv)
diff --git a/build/file_utils.py b/build/file_utils.py
new file mode 100644
index 0000000..1559a9b
--- /dev/null
+++ b/build/file_utils.py
@@ -0,0 +1,49 @@
+# Copyright 2018 - The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""File-related utilities."""
+
+
+import os
+import shutil
+import tempfile
+
+
+def make_parent_dirs(file_path):
+ """Creates parent directories for the file_path."""
+ if os.path.exists(file_path):
+ return
+
+ parent_dir = os.path.dirname(file_path)
+ if parent_dir and not os.path.exists(parent_dir):
+ os.makedirs(parent_dir)
+
+
+def filter_out(pattern_files, input_file):
+ """"Removes lines in input_file that match any line in pattern_files."""
+
+ # Prepares patterns.
+ patterns = []
+ for f in pattern_files:
+ patterns.extend(open(f).readlines())
+
+ # Copy lines that are not in the pattern.
+ tmp_output = tempfile.NamedTemporaryFile()
+ with open(input_file, 'r') as in_file:
+ tmp_output.writelines(line for line in in_file.readlines()
+ if line not in patterns)
+ tmp_output.flush()
+
+ # Replaces the input_file.
+ shutil.copyfile(tmp_output.name, input_file)