diff options
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/clinic/sysmodule.c.h | 78 | ||||
| -rw-r--r-- | Python/initconfig.c | 65 | ||||
| -rw-r--r-- | Python/sysmodule.c | 46 |
3 files changed, 186 insertions, 3 deletions
diff --git a/Python/clinic/sysmodule.c.h b/Python/clinic/sysmodule.c.h index ddf01a7..6864b8b 100644 --- a/Python/clinic/sysmodule.c.h +++ b/Python/clinic/sysmodule.c.h @@ -745,6 +745,82 @@ exit: #endif /* defined(USE_MALLOPT) */ +PyDoc_STRVAR(sys_get_int_max_str_digits__doc__, +"get_int_max_str_digits($module, /)\n" +"--\n" +"\n" +"Set the maximum string digits limit for non-binary int<->str conversions."); + +#define SYS_GET_INT_MAX_STR_DIGITS_METHODDEF \ + {"get_int_max_str_digits", (PyCFunction)sys_get_int_max_str_digits, METH_NOARGS, sys_get_int_max_str_digits__doc__}, + +static PyObject * +sys_get_int_max_str_digits_impl(PyObject *module); + +static PyObject * +sys_get_int_max_str_digits(PyObject *module, PyObject *Py_UNUSED(ignored)) +{ + return sys_get_int_max_str_digits_impl(module); +} + +PyDoc_STRVAR(sys_set_int_max_str_digits__doc__, +"set_int_max_str_digits($module, /, maxdigits)\n" +"--\n" +"\n" +"Set the maximum string digits limit for non-binary int<->str conversions."); + +#define SYS_SET_INT_MAX_STR_DIGITS_METHODDEF \ + {"set_int_max_str_digits", _PyCFunction_CAST(sys_set_int_max_str_digits), METH_FASTCALL|METH_KEYWORDS, sys_set_int_max_str_digits__doc__}, + +static PyObject * +sys_set_int_max_str_digits_impl(PyObject *module, int maxdigits); + +static PyObject * +sys_set_int_max_str_digits(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames) +{ + PyObject *return_value = NULL; + #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE) + + #define NUM_KEYWORDS 1 + static struct { + PyGC_Head _this_is_not_used; + PyObject_VAR_HEAD + PyObject *ob_item[NUM_KEYWORDS]; + } _kwtuple = { + .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS) + .ob_item = { &_Py_ID(maxdigits), }, + }; + #undef NUM_KEYWORDS + #define KWTUPLE (&_kwtuple.ob_base.ob_base) + + #else // !Py_BUILD_CORE + # define KWTUPLE NULL + #endif // !Py_BUILD_CORE + + static const char * const _keywords[] = {"maxdigits", NULL}; + static _PyArg_Parser _parser = { + .keywords = _keywords, + .fname = "set_int_max_str_digits", + .kwtuple = KWTUPLE, + }; + #undef KWTUPLE + PyObject *argsbuf[1]; + int maxdigits; + + args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 1, 1, 0, argsbuf); + if (!args) { + goto exit; + } + maxdigits = _PyLong_AsInt(args[0]); + if (maxdigits == -1 && PyErr_Occurred()) { + goto exit; + } + return_value = sys_set_int_max_str_digits_impl(module, maxdigits); + +exit: + return return_value; +} + PyDoc_STRVAR(sys_getrefcount__doc__, "getrefcount($module, object, /)\n" "--\n" @@ -1267,4 +1343,4 @@ sys_is_stack_trampoline_active(PyObject *module, PyObject *Py_UNUSED(ignored)) #ifndef SYS_GETANDROIDAPILEVEL_METHODDEF #define SYS_GETANDROIDAPILEVEL_METHODDEF #endif /* !defined(SYS_GETANDROIDAPILEVEL_METHODDEF) */ -/*[clinic end generated code: output=43b44240211afe95 input=a9049054013a1b77]*/ +/*[clinic end generated code: output=15318cdd96b62b06 input=a9049054013a1b77]*/ diff --git a/Python/initconfig.c b/Python/initconfig.c index 33a8f27..f18ec40 100644 --- a/Python/initconfig.c +++ b/Python/initconfig.c @@ -3,6 +3,7 @@ #include "pycore_getopt.h" // _PyOS_GetOpt() #include "pycore_initconfig.h" // _PyStatus_OK() #include "pycore_interp.h" // _PyInterpreterState.runtime +#include "pycore_long.h" // _PY_LONG_MAX_STR_DIGITS_THRESHOLD #include "pycore_pathconfig.h" // _Py_path_config #include "pycore_pyerrors.h" // _PyErr_Fetch() #include "pycore_pylifecycle.h" // _Py_PreInitializeFromConfig() @@ -124,7 +125,11 @@ The following implementation-specific options are available:\n\ do nothing if is not supported on the current system. The default value is \"off\".\n\ \n\ -X frozen_modules=[on|off]: whether or not frozen modules should be used.\n\ - The default is \"on\" (or \"off\" if you are running a local build)."; + The default is \"on\" (or \"off\" if you are running a local build).\n\ +\n\ +-X int_max_str_digits=number: limit the size of int<->str conversions.\n\ + This helps avoid denial of service attacks when parsing untrusted data.\n\ + The default is sys.int_info.default_max_str_digits. 0 disables."; /* Envvars that don't have equivalent command-line options are listed first */ static const char usage_envvars[] = @@ -144,6 +149,10 @@ static const char usage_envvars[] = " to seed the hashes of str and bytes objects. It can also be set to an\n" " integer in the range [0,4294967295] to get hash values with a\n" " predictable seed.\n" +"PYTHONINTMAXSTRDIGITS: limits the maximum digit characters in an int value\n" +" when converting from a string and when converting an int back to a str.\n" +" A value of 0 disables the limit. Conversions to or from bases 2, 4, 8,\n" +" 16, and 32 are never limited.\n" "PYTHONMALLOC: set the Python memory allocators and/or install debug hooks\n" " on Python memory allocators. Use PYTHONMALLOC=debug to install debug\n" " hooks.\n" @@ -784,6 +793,10 @@ _PyConfig_InitCompatConfig(PyConfig *config) config->code_debug_ranges = 1; } +/* Excluded from public struct PyConfig for backporting reasons. */ +/* default to unconfigured, _PyLong_InitTypes() does the rest */ +int _Py_global_config_int_max_str_digits = -1; + static void config_init_defaults(PyConfig *config) @@ -1762,6 +1775,48 @@ config_init_tracemalloc(PyConfig *config) return _PyStatus_OK(); } +static PyStatus +config_init_int_max_str_digits(PyConfig *config) +{ + int maxdigits; + int valid = 0; + + const char *env = config_get_env(config, "PYTHONINTMAXSTRDIGITS"); + if (env) { + if (!_Py_str_to_int(env, &maxdigits)) { + valid = ((maxdigits == 0) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)); + } + if (!valid) { +#define STRINGIFY(VAL) _STRINGIFY(VAL) +#define _STRINGIFY(VAL) #VAL + return _PyStatus_ERR( + "PYTHONINTMAXSTRDIGITS: invalid limit; must be >= " + STRINGIFY(_PY_LONG_MAX_STR_DIGITS_THRESHOLD) + " or 0 for unlimited."); + } + _Py_global_config_int_max_str_digits = maxdigits; + } + + const wchar_t *xoption = config_get_xoption(config, L"int_max_str_digits"); + if (xoption) { + const wchar_t *sep = wcschr(xoption, L'='); + if (sep) { + if (!config_wstr_to_int(sep + 1, &maxdigits)) { + valid = ((maxdigits == 0) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)); + } + } + if (!valid) { + return _PyStatus_ERR( + "-X int_max_str_digits: invalid limit; must be >= " + STRINGIFY(_PY_LONG_MAX_STR_DIGITS_THRESHOLD) + " or 0 for unlimited."); +#undef _STRINGIFY +#undef STRINGIFY + } + _Py_global_config_int_max_str_digits = maxdigits; + } + return _PyStatus_OK(); +} static PyStatus config_init_pycache_prefix(PyConfig *config) @@ -1818,6 +1873,7 @@ config_read_complex_options(PyConfig *config) return status; } } + if (config->perf_profiling < 0) { status = config_init_perf_profiling(config); if (_PyStatus_EXCEPTION(status)) { @@ -1825,6 +1881,13 @@ config_read_complex_options(PyConfig *config) } } + if (_Py_global_config_int_max_str_digits < 0) { + status = config_init_int_max_str_digits(config); + if (_PyStatus_EXCEPTION(status)) { + return status; + } + } + if (config->pycache_prefix == NULL) { status = config_init_pycache_prefix(config); if (_PyStatus_EXCEPTION(status)) { diff --git a/Python/sysmodule.c b/Python/sysmodule.c index 75e6455..a33abb2 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -20,6 +20,7 @@ Data members: #include "pycore_code.h" // _Py_QuickenedCount #include "pycore_frame.h" // _PyInterpreterFrame #include "pycore_initconfig.h" // _PyStatus_EXCEPTION() +#include "pycore_long.h" // _PY_LONG_MAX_STR_DIGITS_THRESHOLD #include "pycore_namespace.h" // _PyNamespace_New() #include "pycore_object.h" // _PyObject_IS_GC() #include "pycore_pathconfig.h" // _PyPathConfig_ComputeSysPath0() @@ -1671,6 +1672,45 @@ sys_mdebug_impl(PyObject *module, int flag) } #endif /* USE_MALLOPT */ + +/*[clinic input] +sys.get_int_max_str_digits + +Set the maximum string digits limit for non-binary int<->str conversions. +[clinic start generated code]*/ + +static PyObject * +sys_get_int_max_str_digits_impl(PyObject *module) +/*[clinic end generated code: output=0042f5e8ae0e8631 input=8dab13e2023e60d5]*/ +{ + PyInterpreterState *interp = _PyInterpreterState_GET(); + return PyLong_FromSsize_t(interp->int_max_str_digits); +} + +/*[clinic input] +sys.set_int_max_str_digits + + maxdigits: int + +Set the maximum string digits limit for non-binary int<->str conversions. +[clinic start generated code]*/ + +static PyObject * +sys_set_int_max_str_digits_impl(PyObject *module, int maxdigits) +/*[clinic end generated code: output=734d4c2511f2a56d input=d7e3f325db6910c5]*/ +{ + PyThreadState *tstate = _PyThreadState_GET(); + if ((!maxdigits) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)) { + tstate->interp->int_max_str_digits = maxdigits; + Py_RETURN_NONE; + } else { + PyErr_Format( + PyExc_ValueError, "maxdigits must be 0 or larger than %d", + _PY_LONG_MAX_STR_DIGITS_THRESHOLD); + return NULL; + } +} + size_t _PySys_GetSizeOf(PyObject *o) { @@ -2186,6 +2226,8 @@ static PyMethodDef sys_methods[] = { SYS_DEACTIVATE_STACK_TRAMPOLINE_METHODDEF SYS_IS_STACK_TRAMPOLINE_ACTIVE_METHODDEF SYS_UNRAISABLEHOOK_METHODDEF + SYS_GET_INT_MAX_STR_DIGITS_METHODDEF + SYS_SET_INT_MAX_STR_DIGITS_METHODDEF #ifdef Py_STATS SYS__STATS_ON_METHODDEF SYS__STATS_OFF_METHODDEF @@ -2686,6 +2728,7 @@ static PyStructSequence_Field flags_fields[] = { {"utf8_mode", "-X utf8"}, {"warn_default_encoding", "-X warn_default_encoding"}, {"safe_path", "-P"}, + {"int_max_str_digits", "-X int_max_str_digits"}, {0} }; @@ -2693,7 +2736,7 @@ static PyStructSequence_Desc flags_desc = { "sys.flags", /* name */ flags__doc__, /* doc */ flags_fields, /* fields */ - 17 + 18 }; static int @@ -2734,6 +2777,7 @@ set_flags_from_config(PyInterpreterState *interp, PyObject *flags) SetFlag(preconfig->utf8_mode); SetFlag(config->warn_default_encoding); SetFlagObj(PyBool_FromLong(config->safe_path)); + SetFlag(_Py_global_config_int_max_str_digits); #undef SetFlagObj #undef SetFlag return 0; |