platform_system_sepolicy/tests/sepolicy_tests.py
Hridya Valsaraju 8c9cf62edb Allow coredomain access to only approved categories of vendor heaps
One of the advantages of the DMA-BUF heaps framework over
ION is that each heap is a separate char device and hence
it is possible to create separate sepolicy permissions to restrict
access to each heap.
In the case of ION, allocation in every heap had to be done through
/dev/ion which meant that there was no away to restrict allocations in
a specific heap.

This patch intends to restrict coredomain access to only approved
categories of vendor heaps. Currently, the only identified category
as per partner feedback is the system-secure heap which is defined
as a heap that allocates from protected memory.

Test: Build, video playback works on CF with ION disabled and
without sepolicy denials
Bug: 175697666

Change-Id: I923d2931c631d05d569e97f6e49145ef71324f3b
2020-12-16 10:08:54 -08:00

180 lines
7 KiB
Python

from optparse import OptionParser
from optparse import Option, OptionValueError
import os
import policy
import re
import sys
#############################################################
# Tests
#############################################################
def TestDataTypeViolations(pol):
return pol.AssertPathTypesHaveAttr(["/data/"], [], "data_file_type")
def TestSystemTypeViolations(pol):
partitions = ["/system/", "/system_ext/", "/product/"]
exceptions = [
# devices before treble don't have a vendor partition
"/system/vendor/",
# overlay files are mounted over vendor
"/product/overlay/",
"/product/vendor_overlay/",
"/system/overlay/",
"/system/product/overlay/",
"/system/product/vendor_overlay/",
"/system/system_ext/overlay/",
"/system_ext/overlay/",
]
return pol.AssertPathTypesHaveAttr(partitions, exceptions, "system_file_type")
def TestProcTypeViolations(pol):
return pol.AssertGenfsFilesystemTypesHaveAttr("proc", "proc_type")
def TestSysfsTypeViolations(pol):
ret = pol.AssertGenfsFilesystemTypesHaveAttr("sysfs", "sysfs_type")
ret += pol.AssertPathTypesHaveAttr(["/sys/"], ["/sys/kernel/debug/",
"/sys/kernel/tracing"], "sysfs_type")
return ret
def TestDebugfsTypeViolations(pol):
ret = pol.AssertGenfsFilesystemTypesHaveAttr("debugfs", "debugfs_type")
ret += pol.AssertGenfsFilesystemTypesHaveAttr("tracefs", "debugfs_type")
ret += pol.AssertPathTypesHaveAttr(["/sys/kernel/debug/",
"/sys/kernel/tracing"], [], "debugfs_type")
return ret
def TestVendorTypeViolations(pol):
partitions = ["/vendor/", "/odm/"]
exceptions = [
"/vendor/etc/selinux/",
"/vendor/odm/etc/selinux/",
"/odm/etc/selinux/",
]
return pol.AssertPathTypesHaveAttr(partitions, exceptions, "vendor_file_type")
def TestCoreDataTypeViolations(pol):
return pol.AssertPathTypesHaveAttr(["/data/"], ["/data/vendor",
"/data/vendor_ce", "/data/vendor_de"], "core_data_file_type")
def TestPropertyTypeViolations(pol):
return pol.AssertPropertyOwnersAreExclusive()
def TestAppDataTypeViolations(pol):
# Types with the app_data_file_type should only be used for app data files
# (/data/data/package.name etc) via seapp_contexts, and never applied
# explicitly to other files.
partitions = [
"/data/",
"/vendor/",
"/odm/",
"/product/",
]
exceptions = [
# These are used for app data files for the corresponding user and
# assorted other files.
# TODO(b/172812577): Use different types for the different purposes
"shell_data_file",
"bluetooth_data_file",
"nfc_data_file",
"radio_data_file",
]
return pol.AssertPathTypesDoNotHaveAttr(partitions, [], "app_data_file_type",
exceptions)
def TestDmaHeapDevTypeViolations(pol):
return pol.AssertPathTypesHaveAttr(["/dev/dma_heap/"], [],
"dmabuf_heap_device_type")
###
# extend OptionParser to allow the same option flag to be used multiple times.
# This is used to allow multiple file_contexts files and tests to be
# specified.
#
class MultipleOption(Option):
ACTIONS = Option.ACTIONS + ("extend",)
STORE_ACTIONS = Option.STORE_ACTIONS + ("extend",)
TYPED_ACTIONS = Option.TYPED_ACTIONS + ("extend",)
ALWAYS_TYPED_ACTIONS = Option.ALWAYS_TYPED_ACTIONS + ("extend",)
def take_action(self, action, dest, opt, value, values, parser):
if action == "extend":
values.ensure_value(dest, []).append(value)
else:
Option.take_action(self, action, dest, opt, value, values, parser)
Tests = [
"TestDataTypeViolators",
"TestProcTypeViolations",
"TestSysfsTypeViolations",
"TestSystemTypeViolators",
"TestDebugfsTypeViolations",
"TestVendorTypeViolations",
"TestCoreDataTypeViolations",
"TestPropertyTypeViolations",
"TestAppDataTypeViolations",
"TestDmaHeapDevTypeViolations",
]
if __name__ == '__main__':
usage = "sepolicy_tests -l $(ANDROID_HOST_OUT)/lib64/libsepolwrap.so "
usage += "-f vendor_file_contexts -f "
usage +="plat_file_contexts -p policy [--test test] [--help]"
parser = OptionParser(option_class=MultipleOption, usage=usage)
parser.add_option("-f", "--file_contexts", dest="file_contexts",
metavar="FILE", action="extend", type="string")
parser.add_option("-p", "--policy", dest="policy", metavar="FILE")
parser.add_option("-l", "--library-path", dest="libpath", metavar="FILE")
parser.add_option("-t", "--test", dest="test", action="extend",
help="Test options include "+str(Tests))
(options, args) = parser.parse_args()
if not options.libpath:
sys.exit("Must specify path to libsepolwrap library\n" + parser.usage)
if not os.path.exists(options.libpath):
sys.exit("Error: library-path " + options.libpath + " does not exist\n"
+ parser.usage)
if not options.policy:
sys.exit("Must specify monolithic policy file\n" + parser.usage)
if not os.path.exists(options.policy):
sys.exit("Error: policy file " + options.policy + " does not exist\n"
+ parser.usage)
if not options.file_contexts:
sys.exit("Error: Must specify file_contexts file(s)\n" + parser.usage)
for f in options.file_contexts:
if not os.path.exists(f):
sys.exit("Error: File_contexts file " + f + " does not exist\n" +
parser.usage)
pol = policy.Policy(options.policy, options.file_contexts, options.libpath)
results = ""
# If an individual test is not specified, run all tests.
if options.test is None or "TestDataTypeViolations" in options.test:
results += TestDataTypeViolations(pol)
if options.test is None or "TestProcTypeViolations" in options.test:
results += TestProcTypeViolations(pol)
if options.test is None or "TestSysfsTypeViolations" in options.test:
results += TestSysfsTypeViolations(pol)
if options.test is None or "TestSystemTypeViolations" in options.test:
results += TestSystemTypeViolations(pol)
if options.test is None or "TestDebugfsTypeViolations" in options.test:
results += TestDebugfsTypeViolations(pol)
if options.test is None or "TestVendorTypeViolations" in options.test:
results += TestVendorTypeViolations(pol)
if options.test is None or "TestCoreDataTypeViolations" in options.test:
results += TestCoreDataTypeViolations(pol)
if options.test is None or "TestPropertyTypeViolations" in options.test:
results += TestPropertyTypeViolations(pol)
if options.test is None or "TestAppDataTypeViolations" in options.test:
results += TestAppDataTypeViolations(pol)
if options.test is None or "TestDmaHeapDevTypeViolations" in options.test:
results += TestDmaHeapDevTypeViolations(pol)
if len(results) > 0:
sys.exit(results)