[Libguestfs] [PATCH 1/2] Add type checking, support integers as value
Peter Wu
peter at lekensteyn.nl
Fri Aug 8 18:39:41 UTC 2014
Before this patch, Python would segfault once you pass a non-string key
or value to node_set_value. It was also not possible to set bytes on
Python 3 as Unicode was assumed (Python 2 was not affected by this).
This patch fixes recognition of bytes for Python 3, but in addition it
recognizes ints (includes 'long' in Python 2) for DWORD (LE + BE) and
QWORDs. For this purpose, a new field was added to the py_set_values
struct (words) to simplify memory allocation (otherwise, malloc must
be tracked somehow).
In addition, more specific exception types have been chosen (TypeError
instead of RuntimeError).
A test is added to avoid future regressions. Note that this test will
crash older versions of hivex.
All tests pass with Python 2.7.5 + 3.3.2 (Fedora 20 x86_64), 2.7.8 +
3.4.1 (Arch Linux x86_64) and 2.6.5 (Ubuntu 10.04 i686).
---
configure.ac | 4 --
generator/generator.ml | 112 ++++++++++++++++++++++++++++++-----------
python/t/300-setvalue-types.py | 76 ++++++++++++++++++++++++++++
3 files changed, 160 insertions(+), 32 deletions(-)
create mode 100644 python/t/300-setvalue-types.py
diff --git a/configure.ac b/configure.ac
index f50daff..4566a32 100644
--- a/configure.ac
+++ b/configure.ac
@@ -345,10 +345,6 @@ AS_IF([test "x$enable_python" != "xno"],
[AC_DEFINE([HAVE_PYCAPSULE_NEW],1,
[Found PyCapsule_New in libpython])],
[],[$PYTHON_BLDLIBRARY])
- AC_CHECK_LIB([c],[PyString_AsString],
- [AC_DEFINE([HAVE_PYSTRING_ASSTRING],1,
- [Found PyString_AsString in libpython])],
- [],[$PYTHON_BLDLIBRARY])
LIBS="$old_LIBS"
fi
diff --git a/generator/generator.ml b/generator/generator.ml
index bcf1966..0aeb24e 100755
--- a/generator/generator.ml
+++ b/generator/generator.ml
@@ -2837,45 +2837,90 @@ put_handle (hive_h *h)
* not be freed.
*/
static int
-get_value (PyObject *v, hive_set_value *ret)
+get_value (PyObject *v, hive_set_value *ret, uint64_t *word)
{
PyObject *obj;
-#ifndef HAVE_PYSTRING_ASSTRING
PyObject *bytes;
-#endif
+
+ if (!PyDict_Check (v)) {
+ PyErr_SetString (PyExc_TypeError, \"expected dictionary type for value\");
+ return -1;
+ }
obj = PyDict_GetItemString (v, \"key\");
if (!obj) {
- PyErr_SetString (PyExc_RuntimeError, \"no 'key' element in dictionary\");
+ PyErr_SetString (PyExc_KeyError, \"no 'key' element in dictionary\");
+ return -1;
+ }
+ if (PyUnicode_Check (obj)) {
+ bytes = PyUnicode_AsUTF8String (obj);
+ if (bytes == NULL) {
+ return -1;
+ }
+ } else if (PyBytes_Check (obj)) {
+ bytes = obj;
+ } else {
+ PyErr_SetString (PyExc_TypeError, \"expected bytes or str type for 'key'\");
return -1;
}
-#ifdef HAVE_PYSTRING_ASSTRING
- ret->key = PyString_AsString (obj);
-#else
- bytes = PyUnicode_AsUTF8String (obj);
ret->key = PyBytes_AS_STRING (bytes);
-#endif
obj = PyDict_GetItemString (v, \"t\");
if (!obj) {
- PyErr_SetString (PyExc_RuntimeError, \"no 't' element in dictionary\");
+ PyErr_SetString (PyExc_KeyError, \"no 't' element in dictionary\");
return -1;
}
ret->t = PyLong_AsLong (obj);
+ if (PyErr_Occurred ()) {
+ PyErr_SetString (PyExc_TypeError, \"expected int type for 't'\");
+ return -1;
+ }
obj = PyDict_GetItemString (v, \"value\");
if (!obj) {
- PyErr_SetString (PyExc_RuntimeError, \"no 'value' element in dictionary\");
+ PyErr_SetString (PyExc_KeyError, \"no 'value' element in dictionary\");
+ return -1;
+ }
+ /* Support bytes and unicode strings. For DWORD and QWORD types, long and
+ * integers are also supported. Caller must ensure sanity of byte buffer
+ * lengths */
+ if (PyUnicode_Check (obj)) {
+ bytes = PyUnicode_AsUTF8String (obj);
+ if (bytes == NULL)
+ return -1;
+ ret->len = PyBytes_GET_SIZE (bytes);
+ ret->value = PyBytes_AS_STRING (bytes);
+ } else if (PyBytes_Check (obj)) {
+ ret->len = PyBytes_GET_SIZE (obj);
+ ret->value = PyBytes_AS_STRING (obj);
+ } else if (ret->t == hive_t_REG_DWORD ||
+ ret->t == hive_t_REG_DWORD_BIG_ENDIAN) {
+ uint32_t d = PyLong_AsLong (obj);
+ if (PyErr_Occurred ()) {
+ PyErr_SetString (PyExc_TypeError, \"expected int type for DWORD value\");
+ return -1;
+ }
+
+ ret->len = sizeof (d);
+ ret->value = (char *) word;
+ if (ret->t == hive_t_REG_DWORD)
+ *(uint32_t *) ret->value = htole32 (d);
+ else
+ *(uint32_t *) ret->value = htobe32 (d);
+ } else if (ret->t == hive_t_REG_QWORD) {
+ uint64_t l = PyLong_AsLongLong (obj);
+ if (PyErr_Occurred ()) {
+ PyErr_SetString (PyExc_TypeError, \"expected int type for QWORD value\");
+ return -1;
+ }
+
+ ret->len = sizeof (l);
+ ret->value = (char *) word;
+ *(uint64_t *) ret->value = htole64 (l);
+ } else {
+ PyErr_SetString (PyExc_TypeError, \"expected bytes or str type for 'value'\");
return -1;
}
-#ifdef HAVE_PYSTRING_ASSTRING
- ret->value = PyString_AsString (obj);
- ret->len = PyString_Size (obj);
-#else
- bytes = PyUnicode_AsUTF8String (obj);
- ret->value = PyBytes_AS_STRING (bytes);
- ret->len = PyBytes_GET_SIZE (bytes);
-#endif
return 0;
}
@@ -2883,6 +2928,7 @@ get_value (PyObject *v, hive_set_value *ret)
typedef struct py_set_values {
size_t nr_values;
hive_set_value *values;
+ uint64_t *words;
} py_set_values;
static int
@@ -2905,13 +2951,21 @@ get_values (PyObject *v, py_set_values *ret)
ret->nr_values = len;
ret->values = malloc (len * sizeof (hive_set_value));
if (!ret->values) {
- PyErr_SetString (PyExc_RuntimeError, strerror (errno));
+ PyErr_NoMemory ();
+ return -1;
+ }
+ /* if the value is a dword/qword, it will be stored here */
+ ret->words = malloc (len * sizeof (uint64_t));
+ if (!ret->words) {
+ free (ret->values);
+ PyErr_NoMemory ();
return -1;
}
for (i = 0; i < len; ++i) {
- if (get_value (PyList_GetItem (v, i), &(ret->values[i])) == -1) {
+ if (get_value (PyList_GetItem (v, i), &(ret->values[i]), &(ret->words[i])) == -1) {
free (ret->values);
+ free (ret->words);
return -1;
}
}
@@ -3070,9 +3124,10 @@ put_val_type (char *val, size_t len, hive_type t)
| ASetValues ->
pr " py_set_values values;\n";
pr " PyObject *py_values;\n"
- | ASetValue ->
- pr " hive_set_value val;\n";
- pr " PyObject *py_val;\n"
+ | ASetValue ->
+ pr " hive_set_value val;\n";
+ pr " PyObject *py_val;\n";
+ pr " uint64_t word;"
) (snd style);
pr "\n";
@@ -3136,8 +3191,8 @@ put_val_type (char *val, size_t len, hive_type t)
| ASetValues ->
pr " if (get_values (py_values, &values) == -1)\n";
pr " return NULL;\n"
- | ASetValue ->
- pr " if (get_value (py_val, &val) == -1)\n";
+ | ASetValue ->
+ pr " if (get_value (py_val, &val, &word) == -1)\n";
pr " return NULL;\n"
) (snd style);
@@ -3151,8 +3206,9 @@ put_val_type (char *val, size_t len, hive_type t)
| AString _ | AStringNullable _
| AOpenFlags | AUnusedFlags -> ()
| ASetValues ->
- pr " free (values.values);\n"
- | ASetValue -> ()
+ pr " free (values.values);\n";
+ pr " free (values.words);\n"
+ | ASetValue -> ()
) (snd style);
(* Check for errors from C library. *)
diff --git a/python/t/300-setvalue-types.py b/python/t/300-setvalue-types.py
new file mode 100644
index 0000000..6d72a59
--- /dev/null
+++ b/python/t/300-setvalue-types.py
@@ -0,0 +1,76 @@
+# Test various possible types for assignment to setvalue
+# Copyright (C) 2014 Peter Wu <peter at lekensteyn.nl>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+import hivex
+import os
+from sys import getrefcount
+
+srcdir = "."
+if "srcdir" in os.environ and os.environ["srcdir"]:
+ srcdir = os.environ["srcdir"]
+
+h = hivex.Hivex ("%s/../images/minimal" % srcdir,
+ write = True)
+
+REG_SZ = 1
+REG_BINARY = 3
+REG_DWORD = 4
+REG_DWORD_BIG_ENDIAN = 5
+REG_QWORD = 11
+
+def set_value (key="test key", t=REG_BINARY, value=b'Val'):
+ global h
+ h.node_set_value (h.root (), {
+ "key": key,
+ "t": t,
+ "value": value
+ })
+
+def test_pass (t, value, exp_bytes):
+ global h
+ key = "test_key"
+ set_value (key, t, value)
+ val = h.node_get_value (h.root (), key)
+ ret_type, ret_value = h.value_value (val)
+ assert t == ret_type, \
+ "expected type {0}, got {1}".format(t, ret_type)
+ assert exp_bytes == ret_value, \
+ "expected value {0}, got {1}".format(exp_bytes, ret_value)
+
+def test_exception (exception_type, **kwargs):
+ try:
+ set_value (**kwargs)
+ raise AssertionError("expected {0}".format(exception_type))
+ except exception_type:
+ pass
+
+# Good weather tests
+test_pass (REG_BINARY, b"\x01\x02", b"\x01\x02")
+test_pass (REG_SZ, u"Val", b"\x56\x61\x6c")
+test_pass (REG_DWORD, 0xabcdef, b'\xef\xcd\xab\x00')
+test_pass (REG_DWORD_BIG_ENDIAN, 0xabcdef, b'\x00\xab\xcd\xef')
+test_pass (REG_QWORD, 0x0123456789abcdef,
+ b'\xef\xcd\xab\x89\x67\x45\x23\x01')
+
+# *WORDs must still accept bytes (the length is not checked)
+test_pass (REG_DWORD, b'\xaa\xbb\xcc', b'\xaa\xbb\xcc')
+
+# Bad weather tests
+test_exception (TypeError, key = 1)
+test_exception (TypeError, t = "meh")
+test_exception (TypeError, t = REG_SZ, value = 1)
+test_exception (TypeError, t = REG_DWORD, value = None)
--
2.0.2
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