diff options
Diffstat (limited to 'toolkit/xre/dllservices/mozglue/gen_dll_blocklist_defs.py')
| -rw-r--r-- | toolkit/xre/dllservices/mozglue/gen_dll_blocklist_defs.py | 755 |
1 files changed, 755 insertions, 0 deletions
diff --git a/toolkit/xre/dllservices/mozglue/gen_dll_blocklist_defs.py b/toolkit/xre/dllservices/mozglue/gen_dll_blocklist_defs.py new file mode 100644 index 0000000000..35e1cc300d --- /dev/null +++ b/toolkit/xre/dllservices/mozglue/gen_dll_blocklist_defs.py @@ -0,0 +1,755 @@ +# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*- +# vim: set filetype=python: +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, You can obtain one at http://mozilla.org/MPL/2.0/. + +import os +from copy import deepcopy +from struct import unpack +from uuid import UUID + +from six import iteritems + +H_HEADER = """/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This file was auto-generated from {0} by gen_dll_blocklist_data.py. */ + +#ifndef mozilla_{1}_h +#define mozilla_{1}_h + +""" + +H_FOOTER = """#endif // mozilla_{1}_h + +""" + +H_DEFS_BEGIN_DEFAULT = """#include "mozilla/WindowsDllBlocklistCommon.h" + +DLL_BLOCKLIST_DEFINITIONS_BEGIN + +""" + +H_DEFS_END_DEFAULT = """ +DLL_BLOCKLIST_DEFINITIONS_END + +""" + +H_BEGIN_LSP = """#include <guiddef.h> + +static const GUID gLayerGuids[] = { + +""" + +H_END_LSP = """ +}; + +""" + +H_BEGIN_A11Y = """#include "mozilla/WindowsDllBlocklistCommon.h" + +DLL_BLOCKLIST_DEFINITIONS_BEGIN_NAMED(gBlockedInprocDlls) + +""" + +# These flag names should match the ones defined in WindowsDllBlocklistInfo.h +FLAGS_DEFAULT = "FLAGS_DEFAULT" +BLOCK_WIN8_AND_OLDER = "BLOCK_WIN8_AND_OLDER" +BLOCK_WIN7_AND_OLDER = "BLOCK_WIN7_AND_OLDER" +USE_TIMESTAMP = "USE_TIMESTAMP" +CHILD_PROCESSES_ONLY = "CHILD_PROCESSES_ONLY" +BROWSER_PROCESS_ONLY = "BROWSER_PROCESS_ONLY" +SUBSTITUTE_LSP_PASSTHROUGH = "SUBSTITUTE_LSP_PASSTHROUGH" +REDIRECT_TO_NOOP_ENTRYPOINT = "REDIRECT_TO_NOOP_ENTRYPOINT" +UTILITY_PROCESSES_ONLY = "UTILITY_PROCESSES_ONLY" +SOCKET_PROCESSES_ONLY = "SOCKET_PROCESSES_ONLY" +GPU_PROCESSES_ONLY = "GPU_PROCESSES_ONLY" +GMPLUGIN_PROCESSES_ONLY = "GMPLUGIN_PROCESSES_ONLY" + +# Only these flags are available in the input script +INPUT_ONLY_FLAGS = { + BLOCK_WIN8_AND_OLDER, + BLOCK_WIN7_AND_OLDER, +} + + +def FILTER_ALLOW_ALL(entry): + # A11y entries are special, so we always exclude those by default + # (so it's not really allowing 'all', but it is simpler to reason about by + # pretending that it is allowing all.) + return not isinstance(entry, A11yBlocklistEntry) + + +def FILTER_DENY_ALL(entry): + return False + + +def FILTER_ALLOW_ONLY_A11Y(entry): + return isinstance(entry, A11yBlocklistEntry) + + +def FILTER_ALLOW_ONLY_LSP(entry): + return isinstance(entry, LspBlocklistEntry) + + +def FILTER_TESTS_ONLY(entry): + return not isinstance(entry, A11yBlocklistEntry) and entry.is_test() + + +def derive_test_key(key): + return key + "_TESTS" + + +ALL_DEFINITION_LISTS = ( + "ALL_PROCESSES", + "BROWSER_PROCESS", + "CHILD_PROCESSES", + "GMPLUGIN_PROCESSES", + "GPU_PROCESSES", + "UTILITY_PROCESSES", + "SOCKET_PROCESSES", +) + + +class BlocklistDescriptor(object): + """This class encapsulates every file that is output from this script. + Each instance has a name, an "input specification", and optional "flag + specification" and "output specification" entries. + """ + + DEFAULT_OUTSPEC = { + "mode": "", + "filter": FILTER_ALLOW_ALL, + "begin": H_DEFS_BEGIN_DEFAULT, + "end": H_DEFS_END_DEFAULT, + } + + FILE_NAME_TPL = "WindowsDllBlocklist{0}Defs" + + OutputDir = None + ExistingFd = None + ExistingFdLeafName = None + + def __init__(self, name, inspec, **kwargs): + """Positional arguments: + + name -- String containing the name of the output list. + + inspec -- One or more members of ALL_DEFINITION_LISTS. The input used + for this blocklist file is the union of all lists specified by this + variable. + + Keyword arguments: + + outspec -- an optional list of dicts that specify how the lists output + will be written out to a file. Each dict may contain the following keys: + + 'mode' -- a string that specifies a mode that is used when writing + out list entries to this particular output. This is passed in as the + mode argument to DllBlocklistEntry's write method. + + 'filter' -- a function that, given a blocklist entry, decides + whether or not that entry shall be included in this output file. + + 'begin' -- a string that is written to the output file after writing + the file's header, but prior to writing out any blocklist entries. + + 'end' -- a string that is written to the output file after writing + out any blocklist entries but before the file's footer. + + Any unspecified keys will be assigned default values. + + flagspec -- an optional dict whose keys consist of one or more of the + list names from inspec. Each corresponding value is a set of flags that + should be applied to each entry from that list. For example, the + flagspec: + + {'CHILD_PROCESSES': {CHILD_PROCESSES_ONLY}} + + causes any blocklist entries from the CHILD_PROCESSES list to be output + with the CHILD_PROCESSES_ONLY flag set. + + """ + + self._name = name + + # inspec's elements must all come from ALL_DEFINITION_LISTS + assert not (set(inspec).difference(set(ALL_DEFINITION_LISTS))) + + # Internally to the descriptor, we store input specifications as a dict + # that maps each input blocklist name to the set of flags to be applied + # to each entry in that blocklist. + self._inspec = {blocklist: set() for blocklist in inspec} + + self._outspecs = kwargs.get("outspec", BlocklistDescriptor.DEFAULT_OUTSPEC) + if isinstance(self._outspecs, dict): + # _outspecs should always be stored as a list of dicts + self._outspecs = [self._outspecs] + + flagspecs = kwargs.get("flagspec", dict()) + # flagspec's keys must all come from ALL_DEFINITION_LISTS + assert not (set(flagspecs.keys()).difference(set(self._inspec.keys()))) + + # Merge the flags from flagspec into _inspec's sets + for blocklist, flagspec in iteritems(flagspecs): + spec = self._inspec[blocklist] + if not isinstance(spec, set): + raise TypeError("Flag spec for list %s must be a set!" % blocklist) + spec.update(flagspec) + + @staticmethod + def set_output_fd(fd): + """The build system has already provided an open file descriptor for + one of our outputs. We save that here so that we may use that fd once + we're ready to process that fd's file. We also obtain the output dir for + use as the base directory for the other output files that we open. + """ + BlocklistDescriptor.ExistingFd = fd + ( + BlocklistDescriptor.OutputDir, + BlocklistDescriptor.ExistingFdLeafName, + ) = os.path.split(fd.name) + + @staticmethod + def ensure_no_dupes(defs): + """Ensure that defs does not contain any dupes. We raise a ValueError + because this is a bug in the input and requires developer intervention. + """ + seen = set() + for e in defs: + name = e.get_name() + if name not in seen: + seen.add(name) + else: + raise ValueError("Duplicate entry found: %s" % name) + + @staticmethod + def get_test_entries(exec_env, blocklist): + """Obtains all test entries for the corresponding blocklist, and also + ensures that each entry has its test flag set. + + Positional arguments: + + exec_env -- dict containing the globals that were passed to exec to + when the input script was run. + + blocklist -- The name of the blocklist to obtain tests from. This + should be one of the members of ALL_DEFINITION_LISTS + """ + test_key = derive_test_key(blocklist) + + def set_is_test(elem): + elem.set_is_test() + return elem + + return map(set_is_test, exec_env[test_key]) + + def gen_list(self, exec_env, filter_func): + """Generates a sorted list of blocklist entries from the input script, + filtered via filter_func. + + Positional arguments: + + exec_env -- dict containing the globals that were passed to exec to + when the input script was run. This function expects exec_env to + contain lists of blocklist entries, keyed using one of the members of + ALL_DEFINITION_LISTS. + + filter_func -- a filter function that evaluates each blocklist entry + to determine whether or not it should be included in the results. + """ + + # This list contains all the entries across all blocklists that we + # potentially want to process + unified_list = [] + + # For each blocklist specified in the _inspec, we query the globals + # for their entries, add any flags, and then add them to the + # unified_list. + for blocklist, listflags in iteritems(self._inspec): + + def add_list_flags(elem): + # We deep copy so that flags set for an entry in one blocklist + # do not interfere with flags set for an entry in a different + # list. + result = deepcopy(elem) + result.add_flags(listflags) + return result + + # We add list flags *before* filtering because the filters might + # want to access flags as part of their operation. + unified_list.extend(map(add_list_flags, exec_env[blocklist])) + + # We also add any test entries for the lists specified by _inspec + unified_list.extend( + map(add_list_flags, self.get_test_entries(exec_env, blocklist)) + ) + + # Now we filter out any unwanted list entries + filtered_list = filter(filter_func, unified_list) + + # Sort the list on entry name so that the blocklist code may use + # binary search if it so chooses. + return sorted(filtered_list, key=lambda e: e.get_name()) + + @staticmethod + def get_fd(outspec_leaf_name): + """If BlocklistDescriptor.ExistingFd corresponds to outspec_leaf_name, + then we return that. Otherwise, we construct a new absolute path to + outspec_leaf_name and open a new file descriptor for writing. + """ + if ( + not BlocklistDescriptor.ExistingFd + or BlocklistDescriptor.ExistingFdLeafName != outspec_leaf_name + ): + new_name = os.path.join(BlocklistDescriptor.OutputDir, outspec_leaf_name) + return open(new_name, "w") + + fd = BlocklistDescriptor.ExistingFd + BlocklistDescriptor.ExistingFd = None + return fd + + def write(self, src_file, exec_env): + """Write out all output files that are specified by this descriptor. + + Positional arguments: + + src_file -- name of the input file from which the lists were generated. + + exec_env -- dictionary containing the lists that were parsed from the + input file when it was executed. + """ + + for outspec in self._outspecs: + # Use DEFAULT_OUTSPEC to supply defaults for any unused outspec keys + effective_outspec = BlocklistDescriptor.DEFAULT_OUTSPEC.copy() + effective_outspec.update(outspec) + + entries = self.gen_list(exec_env, effective_outspec["filter"]) + if not entries: + continue + + mode = effective_outspec["mode"] + + # Since each output descriptor may generate output across multiple + # modes, each list is uniquified via the concatenation of our name + # and the mode. + listname = self._name + mode + leafname_no_ext = BlocklistDescriptor.FILE_NAME_TPL.format(listname) + leafname = leafname_no_ext + ".h" + + with self.get_fd(leafname) as output: + print(H_HEADER.format(src_file, leafname_no_ext), file=output, end="") + print(effective_outspec["begin"], file=output, end="") + + for e in entries: + e.write(output, mode) + + print(effective_outspec["end"], file=output, end="") + print(H_FOOTER.format(src_file, leafname_no_ext), file=output, end="") + + +A11Y_OUTPUT_SPEC = { + "filter": FILTER_ALLOW_ONLY_A11Y, + "begin": H_BEGIN_A11Y, +} + +LSP_MODE_GUID = "Guid" + +LSP_OUTPUT_SPEC = [ + { + "mode": LSP_MODE_GUID, + "filter": FILTER_ALLOW_ONLY_LSP, + "begin": H_BEGIN_LSP, + "end": H_END_LSP, + }, +] + +GENERATED_BLOCKLIST_FILES = [ + BlocklistDescriptor("A11y", ["BROWSER_PROCESS"], outspec=A11Y_OUTPUT_SPEC), + BlocklistDescriptor( + "Launcher", + ALL_DEFINITION_LISTS, + flagspec={ + "BROWSER_PROCESS": {BROWSER_PROCESS_ONLY}, + "CHILD_PROCESSES": {CHILD_PROCESSES_ONLY}, + "GMPLUGIN_PROCESSES": {GMPLUGIN_PROCESSES_ONLY}, + "GPU_PROCESSES": {GPU_PROCESSES_ONLY}, + "UTILITY_PROCESSES": {UTILITY_PROCESSES_ONLY}, + "SOCKET_PROCESSES": {SOCKET_PROCESSES_ONLY}, + }, + ), + BlocklistDescriptor( + "Legacy", + ALL_DEFINITION_LISTS, + flagspec={ + "BROWSER_PROCESS": {BROWSER_PROCESS_ONLY}, + "CHILD_PROCESSES": {CHILD_PROCESSES_ONLY}, + "GMPLUGIN_PROCESSES": {GMPLUGIN_PROCESSES_ONLY}, + "GPU_PROCESSES": {GPU_PROCESSES_ONLY}, + "UTILITY_PROCESSES": {UTILITY_PROCESSES_ONLY}, + "SOCKET_PROCESSES": {SOCKET_PROCESSES_ONLY}, + }, + ), + # Roughed-in for the moment; we'll enable this in bug 1238735 + # BlocklistDescriptor('LSP', ALL_DEFINITION_LISTS, outspec=LSP_OUTPUT_SPEC), + BlocklistDescriptor( + "Test", ALL_DEFINITION_LISTS, outspec={"filter": FILTER_TESTS_ONLY} + ), +] + + +class PETimeStamp(object): + def __init__(self, ts): + max_timestamp = (2 ** 32) - 1 + if ts < 0 or ts > max_timestamp: + raise ValueError("Invalid timestamp value") + self._value = ts + + def __str__(self): + return "0x%08XU" % self._value + + +class Version(object): + """Encapsulates a DLL version.""" + + ALL_VERSIONS = 0xFFFFFFFFFFFFFFFF + UNVERSIONED = 0 + + def __init__(self, *args): + """There are multiple ways to construct a Version: + + As a tuple containing four elements (recommended); + As four integral arguments; + As a PETimeStamp; + As a long integer. + + The tuple and list formats require the value of each element to be + between 0 and 0xFFFF, inclusive. + """ + + self._ver = Version.UNVERSIONED + + if len(args) == 1: + if isinstance(args[0], tuple): + self.validate_iterable(args[0]) + + self._ver = "MAKE_VERSION%r" % (args[0],) + elif isinstance(args[0], PETimeStamp): + self._ver = args[0] + else: + self._ver = int(args[0]) + elif len(args) == 4: + self.validate_iterable(args) + + self._ver = "MAKE_VERSION%r" % (tuple(args),) + else: + raise ValueError("Bad arguments to Version constructor") + + def validate_iterable(self, arg): + if len(arg) != 4: + raise ValueError("Versions must be a 4-tuple") + + for component in arg: + if not isinstance(component, int) or component < 0 or component > 0xFFFF: + raise ValueError( + "Each version component must be a 16-bit " "unsigned integer" + ) + + def build_long(self, args): + self.validate_iterable(args) + return ( + (int(args[0]) << 48) + | (int(args[1]) << 32) + | (int(args[2]) << 16) + | int(args[3]) + ) + + def is_timestamp(self): + return isinstance(self._ver, PETimeStamp) + + def __str__(self): + if isinstance(self._ver, int): + if self._ver == Version.ALL_VERSIONS: + return "DllBlockInfo::ALL_VERSIONS" + + if self._ver == Version.UNVERSIONED: + return "DllBlockInfo::UNVERSIONED" + + return "0x%016XULL" % self._ver + + return str(self._ver) + + +class DllBlocklistEntry(object): + TEST_CONDITION = "defined(ENABLE_TESTS)" + + def __init__(self, name, ver, flags=(), **kwargs): + """Positional arguments: + + name -- The leaf name of the DLL. + + ver -- The maximum version to be blocked. NB: The comparison used by the + blocklist is <=, so you should specify the last bad version, as opposed + to the first good version. + + flags -- iterable containing the flags that should be applicable to + this blocklist entry. + + Keyword arguments: + + condition -- a string containing a C++ preprocessor expression. This + condition is written as a condition for an #if/#endif block that is + generated around the entry during output. + """ + + self.check_ascii(name) + self._name = name.lower() + self._ver = Version(ver) + + self._flags = set() + self.add_flags(flags) + if self._ver.is_timestamp(): + self._flags.add(USE_TIMESTAMP) + + self._cond = kwargs.get("condition", set()) + if isinstance(self._cond, str): + self._cond = {self._cond} + + @staticmethod + def check_ascii(name): + try: + # Supported in Python 3.7 + if not name.isascii(): + raise ValueError('DLL name "%s" must be ASCII!' % name) + return + except AttributeError: + pass + + try: + name.encode("ascii") + except UnicodeEncodeError: + raise ValueError('DLL name "%s" must be ASCII!' % name) + + def get_name(self): + return self._name + + def set_condition(self, cond): + self._cond.add(cond) + + def get_condition(self): + if len(self._cond) == 1: + fmt = "{0}" + else: + fmt = "({0})" + + return " && ".join([fmt.format(c) for c in self._cond]) + + def set_is_test(self): + self.set_condition(DllBlocklistEntry.TEST_CONDITION) + + def is_test(self): + return self._cond and DllBlocklistEntry.TEST_CONDITION in self._cond + + def add_flags(self, new_flags): + if isinstance(new_flags, str): + self._flags.add(new_flags) + else: + self._flags.update(new_flags) + + @staticmethod + def get_flag_string(flag): + return "mozilla::DllBlockInfoFlags::" + flag + + def get_flags_list(self): + return self._flags + + def write(self, output, mode): + if self._cond: + print("#if %s" % self.get_condition(), file=output) + + flags_str = "" + + flags = self.get_flags_list() + if flags: + flags_str = ", " + " | ".join(map(self.get_flag_string, flags)) + + entry_str = ' DLL_BLOCKLIST_ENTRY("%s", %s%s)' % ( + self._name, + str(self._ver), + flags_str, + ) + print(entry_str, file=output) + + if self._cond: + print("#endif // %s" % self.get_condition(), file=output) + + +class A11yBlocklistEntry(DllBlocklistEntry): + """Represents a blocklist entry for injected a11y DLLs. This class does + not need to do anything special compared to a DllBlocklistEntry; we just + use this type to distinguish a11y entries from "regular" blocklist entries. + """ + + def __init__(self, name, ver, flags=(), **kwargs): + """These arguments are identical to DllBlocklistEntry.__init__""" + + super(A11yBlocklistEntry, self).__init__(name, ver, flags, **kwargs) + + +class RedirectToNoOpEntryPoint(DllBlocklistEntry): + """Represents a blocklist entry to hook the entrypoint into a function + just returning TRUE to keep a module alive and harmless. + This entry is intended to block a DLL which is injected by IAT patching + which is planted by a kernel callback routine for LoadImage because + blocking such a DLL makes a process fail to launch. + """ + + def __init__(self, name, ver, flags=(), **kwargs): + """These arguments are identical to DllBlocklistEntry.__init__""" + + super(RedirectToNoOpEntryPoint, self).__init__(name, ver, flags, **kwargs) + + def get_flags_list(self): + flags = super(RedirectToNoOpEntryPoint, self).get_flags_list() + # RedirectToNoOpEntryPoint items always include the following flag + flags.add(REDIRECT_TO_NOOP_ENTRYPOINT) + return flags + + +class LspBlocklistEntry(DllBlocklistEntry): + """Represents a blocklist entry for a WinSock Layered Service Provider (LSP).""" + + GUID_UNPACK_FMT_LE = "<IHHBBBBBBBB" + Guids = dict() + + def __init__(self, name, ver, guids, flags=(), **kwargs): + """Positional arguments: + + name -- The leaf name of the DLL. + + ver -- The maximum version to be blocked. NB: The comparison used by the + blocklist is <=, so you should specify the last bad version, as opposed + to the first good version. + + guids -- Either a string or list of strings containing the GUIDs that + uniquely identify the LSP. These GUIDs are generated by the developer of + the LSP and are registered with WinSock alongside the LSP. We record + this GUID as part of the "Winsock_LSP" annotation in our crash reports. + + flags -- iterable containing the flags that should be applicable to + this blocklist entry. + + Keyword arguments: + + condition -- a string containing a C++ preprocessor expression. This + condition is written as a condition for an #if/#endif block that is + generated around the entry during output. + """ + + super(LspBlocklistEntry, self).__init__(name, ver, flags, **kwargs) + if not guids: + raise ValueError("Missing GUID(s)!") + + if isinstance(guids, str): + self.insert(UUID(guids), name) + else: + for guid in guids: + self.insert(UUID(guid), name) + + def insert(self, guid, name): + # Some explanation here: Multiple DLLs (and thus multiple instances of + # LspBlocklistEntry) may share the same GUIDs. To ensure that we do not + # have any duplicates, we store each GUID in a class variable, Guids. + # We include the original DLL name from the blocklist definitions so + # that we may output a comment above each GUID indicating which entries + # correspond to which GUID. + LspBlocklistEntry.Guids.setdefault(guid, []).append(name) + + def get_flags_list(self): + flags = super(LspBlocklistEntry, self).get_flags_list() + # LSP entries always include the following flag + flags.add(SUBSTITUTE_LSP_PASSTHROUGH) + return flags + + @staticmethod + def as_c_struct(guid, names): + parts = unpack(LspBlocklistEntry.GUID_UNPACK_FMT_LE, guid.bytes_le) + str_guid = ( + " // %r\n // {%s}\n { 0x%08x, 0x%04x, 0x%04x, " + "{ 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x, 0x%02x }" + " }" + % ( + names, + str(guid), + parts[0], + parts[1], + parts[2], + parts[3], + parts[4], + parts[5], + parts[6], + parts[7], + parts[8], + parts[9], + parts[10], + ) + ) + return str_guid + + def write(self, output, mode): + if mode != LSP_MODE_GUID: + super(LspBlocklistEntry, self).write(output, mode) + return + + # We dump the entire contents of Guids on the first call, and then + # clear it. Remaining invocations of this method are no-ops. + if LspBlocklistEntry.Guids: + result = ",\n".join( + [ + self.as_c_struct(guid, names) + for guid, names in iteritems(LspBlocklistEntry.Guids) + ] + ) + print(result, file=output) + LspBlocklistEntry.Guids.clear() + + +def exec_script_file(script_name, globals): + with open(script_name) as script: + exec(compile(script.read(), script_name, "exec"), globals) + + +def gen_blocklists(first_fd, defs_filename): + + BlocklistDescriptor.set_output_fd(first_fd) + + # exec_env defines the global variables that will be present in the + # execution environment when defs_filename is run by exec. + exec_env = { + # Add the blocklist entry types + "A11yBlocklistEntry": A11yBlocklistEntry, + "DllBlocklistEntry": DllBlocklistEntry, + "LspBlocklistEntry": LspBlocklistEntry, + "RedirectToNoOpEntryPoint": RedirectToNoOpEntryPoint, + # Add the special version types + "ALL_VERSIONS": Version.ALL_VERSIONS, + "UNVERSIONED": Version.UNVERSIONED, + "PETimeStamp": PETimeStamp, + } + + # Import definition lists into exec_env + for defname in ALL_DEFINITION_LISTS: + exec_env[defname] = [] + # For each defname, add a special list for test-only entries + exec_env[derive_test_key(defname)] = [] + + # Import flags into exec_env + exec_env.update({flag: flag for flag in INPUT_ONLY_FLAGS}) + + # Now execute the input script with exec_env providing the globals + exec_script_file(defs_filename, exec_env) + + # Tell the output descriptors to write out the output files. + for desc in GENERATED_BLOCKLIST_FILES: + desc.write(defs_filename, exec_env) |