from ptrace.syscall.syscall_argument import ARGUMENT_CALLBACK
from .syscall_filters import SYSCALL_FILTERS
from .utilities import T, SYSCALL_REGISTER, RETURN_VALUE_REGISTER
# Python 2/3 compatibility hack
# Source: http://stackoverflow.com/a/7321970
try:
input = raw_input
except NameError:
pass
# Register filtered syscalls with python-ptrace so they are parsed correctly
SYSCALL_PROTOTYPES.clear()
FILENAME_ARGUMENTS.clear()
for syscall_filter in SYSCALL_FILTERS:
SYSCALL_PROTOTYPES[syscall_filter.name] = syscall_filter.signature
for argument in syscall_filter.signature[1]:
if argument[0] == "const char *":
FILENAME_ARGUMENTS.add(argument[1])
# Turn list into dictionary indexed by syscall name for fast filter retrieval
SYSCALL_FILTERS = {syscall_filter.name: syscall_filter for syscall_filter in SYSCALL_FILTERS}
# Prevent python-ptrace from decoding arguments to keep raw numerical values
SYSCALL_ARG_DICT.clear()
ARGUMENT_CALLBACK.clear()
def main(argv=sys.argv[1:]):
filter_scopes = sorted(SYSCALL_FILTERS.keys())
# Insert positional argument separator, if not already present
if "--" not in argv:
for i, argument in enumerate(argv):
if not argument.startswith("-"):
argv.insert(i, "--")
break
arg_parser = ArgumentParser(
prog="maybe",
usage="%(prog)s [options] command [argument ...]",
description="Run a command without the ability to make changes to your system " +
"and list the changes it would have made.",
epilog="For more information, to report issues or to contribute, " +
"visit https://github.com/p-e-w/maybe.",
)
arg_parser.add_argument("command", nargs="+", help="the command to run under maybe's control")
arg_group = arg_parser.add_mutually_exclusive_group()
arg_group.add_argument("-a", "--allow", nargs="+", choices=filter_scopes, metavar="OPERATION",
help="allow the command to perform the specified operation(s). " +
"all other operations will be denied. " +
"possible values for %(metavar)s are: %(choices)s")
arg_group.add_argument("-d", "--deny", nargs="+", choices=filter_scopes, metavar="OPERATION",
help="deny the command the specified operation(s). " +
"all other operations will be allowed. " +
"see --allow for a list of possible values for %(metavar)s. " +
"--allow and --deny cannot be combined")
arg_parser.add_argument("-l", "--list-only", action="store_true",
help="list operations without header, indentation and rerun prompt")
arg_parser.add_argument("--style-output", choices=["yes", "no", "auto"], default="auto",
help="colorize output using ANSI escape sequences (yes/no) " +
"or automatically decide based on whether stdout is a terminal (auto, default)")
arg_parser.add_argument("-v", "--verbose", action="count",
help="if specified once, print every filtered syscall. " +
"if specified twice, print every syscall, highlighting filtered syscalls")
arg_parser.add_argument("--version", action="version", version="%(prog)s 0.4.0")
args = arg_parser.parse_args(argv)
initialize_terminal(args.style_output)
if args.allow is not None:
filter_scopes = set(filter_scopes) - set(args.allow)
elif args.deny is not None:
filter_scopes = args.deny
SYSCALL_PROTOTYPES.clear()
FILENAME_ARGUMENTS.clear()
syscall_filters = {}
for filter_scope in filter_scopes:
for syscall_filter in SYSCALL_FILTERS[filter_scope]:
syscall_filters[syscall_filter.name] = syscall_filter
# Register filtered syscalls with python-ptrace so they are parsed correctly
SYSCALL_PROTOTYPES[syscall_filter.name] = syscall_filter.signature
for argument in syscall_filter.signature[1]:
if argument[0] == "const char *":
FILENAME_ARGUMENTS.add(argument[1])
# Prevent python-ptrace from decoding arguments to keep raw numerical values
SYSCALL_ARG_DICT.clear()
ARGUMENT_CALLBACK.clear()
# This is basically "shlex.join"
command = " ".join([(("'%s'" % arg) if (" " in arg) else arg) for arg in args.command])
try:
args.command[0] = locateProgram(args.command[0])
pid = createChild(args.command, False)
except Exception as error:
print(T.red("Error executing %s: %s." % (T.bold(command) + T.red, error)))
return 1
debugger = PtraceDebugger()
debugger.traceExec()
try:
debugger.traceFork()
except DebuggerError:
print(T.yellow("Warning: Running without traceFork support. " +
"Syscalls from subprocesses can not be intercepted."))
process = debugger.addProcess(pid, True)
process.syscall()
try:
operations = get_operations(debugger, syscall_filters, args.verbose)
except Exception as error:
print(T.red("Error tracing process: %s." % error))
return 1
except KeyboardInterrupt:
print(T.yellow("%s terminated by keyboard interrupt." % (T.bold(command) + T.yellow)))
return 2
finally:
# Cut down all processes no matter what happens
# to prevent them from doing any damage
debugger.quit()
if operations:
if not args.list_only:
print("%s has prevented %s from performing %d file system operations:\n" %
(T.bold("maybe"), T.bold(command), len(operations)))
for operation in operations:
print(("" if args.list_only else " ") + operation)
if not args.list_only:
try:
choice = input("\nDo you want to rerun %s and permit these operations? [y/N] " % T.bold(command))
except KeyboardInterrupt:
choice = ""
# Ctrl+C does not print a newline automatically
print("")
if choice.lower() == "y":
subprocess.call(args.command)
else:
print("%s has not detected any file system operations from %s." %
(T.bold("maybe"), T.bold(command)))
