cpython/Modules/pwdmodule.c
Serhiy Storchaka f7eae0adfc [security] bpo-13617: Reject embedded null characters in wchar* strings. (#2302)
Based on patch by Victor Stinner.

Add private C API function _PyUnicode_AsUnicode() which is similar to
PyUnicode_AsUnicode(), but checks for null characters.
2017-06-28 08:30:06 +03:00

248 lines
6.0 KiB
C

/* UNIX password file access module */
#include "Python.h"
#include "posixmodule.h"
#include <pwd.h>
#include "clinic/pwdmodule.c.h"
/*[clinic input]
module pwd
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=60f628ef356b97b6]*/
static PyStructSequence_Field struct_pwd_type_fields[] = {
{"pw_name", "user name"},
{"pw_passwd", "password"},
{"pw_uid", "user id"},
{"pw_gid", "group id"},
{"pw_gecos", "real name"},
{"pw_dir", "home directory"},
{"pw_shell", "shell program"},
{0}
};
PyDoc_STRVAR(struct_passwd__doc__,
"pwd.struct_passwd: Results from getpw*() routines.\n\n\
This object may be accessed either as a tuple of\n\
(pw_name,pw_passwd,pw_uid,pw_gid,pw_gecos,pw_dir,pw_shell)\n\
or via the object attributes as named in the above tuple.");
static PyStructSequence_Desc struct_pwd_type_desc = {
"pwd.struct_passwd",
struct_passwd__doc__,
struct_pwd_type_fields,
7,
};
PyDoc_STRVAR(pwd__doc__,
"This module provides access to the Unix password database.\n\
It is available on all Unix versions.\n\
\n\
Password database entries are reported as 7-tuples containing the following\n\
items from the password database (see `<pwd.h>'), in order:\n\
pw_name, pw_passwd, pw_uid, pw_gid, pw_gecos, pw_dir, pw_shell.\n\
The uid and gid items are integers, all others are strings. An\n\
exception is raised if the entry asked for cannot be found.");
static int initialized;
static PyTypeObject StructPwdType;
static void
sets(PyObject *v, int i, const char* val)
{
if (val) {
PyObject *o = PyUnicode_DecodeFSDefault(val);
PyStructSequence_SET_ITEM(v, i, o);
}
else {
PyStructSequence_SET_ITEM(v, i, Py_None);
Py_INCREF(Py_None);
}
}
static PyObject *
mkpwent(struct passwd *p)
{
int setIndex = 0;
PyObject *v = PyStructSequence_New(&StructPwdType);
if (v == NULL)
return NULL;
#define SETI(i,val) PyStructSequence_SET_ITEM(v, i, PyLong_FromLong((long) val))
#define SETS(i,val) sets(v, i, val)
SETS(setIndex++, p->pw_name);
#if defined(HAVE_STRUCT_PASSWD_PW_PASSWD) && !defined(__ANDROID__)
SETS(setIndex++, p->pw_passwd);
#else
SETS(setIndex++, "");
#endif
PyStructSequence_SET_ITEM(v, setIndex++, _PyLong_FromUid(p->pw_uid));
PyStructSequence_SET_ITEM(v, setIndex++, _PyLong_FromGid(p->pw_gid));
#if defined(HAVE_STRUCT_PASSWD_PW_GECOS)
SETS(setIndex++, p->pw_gecos);
#else
SETS(setIndex++, "");
#endif
SETS(setIndex++, p->pw_dir);
SETS(setIndex++, p->pw_shell);
#undef SETS
#undef SETI
if (PyErr_Occurred()) {
Py_XDECREF(v);
return NULL;
}
return v;
}
/*[clinic input]
pwd.getpwuid
uidobj: object
/
Return the password database entry for the given numeric user ID.
See `help(pwd)` for more on password database entries.
[clinic start generated code]*/
static PyObject *
pwd_getpwuid(PyObject *module, PyObject *uidobj)
/*[clinic end generated code: output=c4ee1d4d429b86c4 input=ae64d507a1c6d3e8]*/
{
uid_t uid;
struct passwd *p;
if (!_Py_Uid_Converter(uidobj, &uid)) {
if (PyErr_ExceptionMatches(PyExc_OverflowError))
PyErr_Format(PyExc_KeyError,
"getpwuid(): uid not found");
return NULL;
}
if ((p = getpwuid(uid)) == NULL) {
PyObject *uid_obj = _PyLong_FromUid(uid);
if (uid_obj == NULL)
return NULL;
PyErr_Format(PyExc_KeyError,
"getpwuid(): uid not found: %S", uid_obj);
Py_DECREF(uid_obj);
return NULL;
}
return mkpwent(p);
}
/*[clinic input]
pwd.getpwnam
arg: unicode
/
Return the password database entry for the given user name.
See `help(pwd)` for more on password database entries.
[clinic start generated code]*/
static PyObject *
pwd_getpwnam_impl(PyObject *module, PyObject *arg)
/*[clinic end generated code: output=6abeee92430e43d2 input=d5f7e700919b02d3]*/
{
char *name;
struct passwd *p;
PyObject *bytes, *retval = NULL;
if ((bytes = PyUnicode_EncodeFSDefault(arg)) == NULL)
return NULL;
/* check for embedded null bytes */
if (PyBytes_AsStringAndSize(bytes, &name, NULL) == -1)
goto out;
if ((p = getpwnam(name)) == NULL) {
PyErr_Format(PyExc_KeyError,
"getpwnam(): name not found: %s", name);
goto out;
}
retval = mkpwent(p);
out:
Py_DECREF(bytes);
return retval;
}
#ifdef HAVE_GETPWENT
/*[clinic input]
pwd.getpwall
Return a list of all available password database entries, in arbitrary order.
See help(pwd) for more on password database entries.
[clinic start generated code]*/
static PyObject *
pwd_getpwall_impl(PyObject *module)
/*[clinic end generated code: output=4853d2f5a0afac8a input=d7ecebfd90219b85]*/
{
PyObject *d;
struct passwd *p;
if ((d = PyList_New(0)) == NULL)
return NULL;
setpwent();
while ((p = getpwent()) != NULL) {
PyObject *v = mkpwent(p);
if (v == NULL || PyList_Append(d, v) != 0) {
Py_XDECREF(v);
Py_DECREF(d);
endpwent();
return NULL;
}
Py_DECREF(v);
}
endpwent();
return d;
}
#endif
static PyMethodDef pwd_methods[] = {
PWD_GETPWUID_METHODDEF
PWD_GETPWNAM_METHODDEF
#ifdef HAVE_GETPWENT
PWD_GETPWALL_METHODDEF
#endif
{NULL, NULL} /* sentinel */
};
static struct PyModuleDef pwdmodule = {
PyModuleDef_HEAD_INIT,
"pwd",
pwd__doc__,
-1,
pwd_methods,
NULL,
NULL,
NULL,
NULL
};
PyMODINIT_FUNC
PyInit_pwd(void)
{
PyObject *m;
m = PyModule_Create(&pwdmodule);
if (m == NULL)
return NULL;
if (!initialized) {
if (PyStructSequence_InitType2(&StructPwdType,
&struct_pwd_type_desc) < 0)
return NULL;
initialized = 1;
}
Py_INCREF((PyObject *) &StructPwdType);
PyModule_AddObject(m, "struct_passwd", (PyObject *) &StructPwdType);
return m;
}