289 lines
9.9 KiB
C
289 lines
9.9 KiB
C
|
|
/* Support for dynamic loading of extension modules */
|
|
|
|
#include "Python.h"
|
|
|
|
#ifdef HAVE_DIRECT_H
|
|
#include <direct.h>
|
|
#endif
|
|
#include <ctype.h>
|
|
|
|
#include "importdl.h"
|
|
#include "patchlevel.h"
|
|
#include <windows.h>
|
|
|
|
#ifdef _DEBUG
|
|
#define PYD_DEBUG_SUFFIX "_d"
|
|
#else
|
|
#define PYD_DEBUG_SUFFIX ""
|
|
#endif
|
|
|
|
#ifdef PYD_PLATFORM_TAG
|
|
#define PYD_TAGGED_SUFFIX PYD_DEBUG_SUFFIX ".cp" Py_STRINGIFY(PY_MAJOR_VERSION) Py_STRINGIFY(PY_MINOR_VERSION) "-" PYD_PLATFORM_TAG ".pyd"
|
|
#else
|
|
#define PYD_TAGGED_SUFFIX PYD_DEBUG_SUFFIX ".cp" Py_STRINGIFY(PY_MAJOR_VERSION) Py_STRINGIFY(PY_MINOR_VERSION) ".pyd"
|
|
#endif
|
|
|
|
#define PYD_UNTAGGED_SUFFIX PYD_DEBUG_SUFFIX ".pyd"
|
|
|
|
const char *_PyImport_DynLoadFiletab[] = {
|
|
PYD_TAGGED_SUFFIX,
|
|
PYD_UNTAGGED_SUFFIX,
|
|
NULL
|
|
};
|
|
|
|
/* Function to return the name of the "python" DLL that the supplied module
|
|
directly imports. Looks through the list of imported modules and
|
|
returns the first entry that starts with "python" (case sensitive) and
|
|
is followed by nothing but numbers until the separator (period).
|
|
|
|
Returns a pointer to the import name, or NULL if no matching name was
|
|
located.
|
|
|
|
This function parses through the PE header for the module as loaded in
|
|
memory by the system loader. The PE header is accessed as documented by
|
|
Microsoft in the MSDN PE and COFF specification (2/99), and handles
|
|
both PE32 and PE32+. It only worries about the direct import table and
|
|
not the delay load import table since it's unlikely an extension is
|
|
going to be delay loading Python (after all, it's already loaded).
|
|
|
|
If any magic values are not found (e.g., the PE header or optional
|
|
header magic), then this function simply returns NULL. */
|
|
|
|
#define DWORD_AT(mem) (*(DWORD *)(mem))
|
|
#define WORD_AT(mem) (*(WORD *)(mem))
|
|
|
|
static char *GetPythonImport (HINSTANCE hModule)
|
|
{
|
|
unsigned char *dllbase, *import_data, *import_name;
|
|
DWORD pe_offset, opt_offset;
|
|
WORD opt_magic;
|
|
int num_dict_off, import_off;
|
|
|
|
/* Safety check input */
|
|
if (hModule == NULL) {
|
|
return NULL;
|
|
}
|
|
|
|
/* Module instance is also the base load address. First portion of
|
|
memory is the MS-DOS loader, which holds the offset to the PE
|
|
header (from the load base) at 0x3C */
|
|
dllbase = (unsigned char *)hModule;
|
|
pe_offset = DWORD_AT(dllbase + 0x3C);
|
|
|
|
/* The PE signature must be "PE\0\0" */
|
|
if (memcmp(dllbase+pe_offset,"PE\0\0",4)) {
|
|
return NULL;
|
|
}
|
|
|
|
/* Following the PE signature is the standard COFF header (20
|
|
bytes) and then the optional header. The optional header starts
|
|
with a magic value of 0x10B for PE32 or 0x20B for PE32+ (PE32+
|
|
uses 64-bits for some fields). It might also be 0x107 for a ROM
|
|
image, but we don't process that here.
|
|
|
|
The optional header ends with a data dictionary that directly
|
|
points to certain types of data, among them the import entries
|
|
(in the second table entry). Based on the header type, we
|
|
determine offsets for the data dictionary count and the entry
|
|
within the dictionary pointing to the imports. */
|
|
|
|
opt_offset = pe_offset + 4 + 20;
|
|
opt_magic = WORD_AT(dllbase+opt_offset);
|
|
if (opt_magic == 0x10B) {
|
|
/* PE32 */
|
|
num_dict_off = 92;
|
|
import_off = 104;
|
|
} else if (opt_magic == 0x20B) {
|
|
/* PE32+ */
|
|
num_dict_off = 108;
|
|
import_off = 120;
|
|
} else {
|
|
/* Unsupported */
|
|
return NULL;
|
|
}
|
|
|
|
/* Now if an import table exists, offset to it and walk the list of
|
|
imports. The import table is an array (ending when an entry has
|
|
empty values) of structures (20 bytes each), which contains (at
|
|
offset 12) a relative address (to the module base) at which a
|
|
string constant holding the import name is located. */
|
|
|
|
if (DWORD_AT(dllbase + opt_offset + num_dict_off) >= 2) {
|
|
/* We have at least 2 tables - the import table is the second
|
|
one. But still it may be that the table size is zero */
|
|
if (0 == DWORD_AT(dllbase + opt_offset + import_off + sizeof(DWORD)))
|
|
return NULL;
|
|
import_data = dllbase + DWORD_AT(dllbase +
|
|
opt_offset +
|
|
import_off);
|
|
while (DWORD_AT(import_data)) {
|
|
import_name = dllbase + DWORD_AT(import_data+12);
|
|
if (strlen(import_name) >= 6 &&
|
|
!strncmp(import_name,"python",6)) {
|
|
char *pch;
|
|
|
|
#ifndef _DEBUG
|
|
/* In a release version, don't claim that python3.dll is
|
|
a Python DLL. */
|
|
if (strcmp(import_name, "python3.dll") == 0) {
|
|
import_data += 20;
|
|
continue;
|
|
}
|
|
#endif
|
|
|
|
/* Ensure python prefix is followed only
|
|
by numbers to the end of the basename */
|
|
pch = import_name + 6;
|
|
#ifdef _DEBUG
|
|
while (*pch && pch[0] != '_' && pch[1] != 'd' && pch[2] != '.') {
|
|
#else
|
|
while (*pch && *pch != '.') {
|
|
#endif
|
|
if (*pch >= '0' && *pch <= '9') {
|
|
pch++;
|
|
} else {
|
|
pch = NULL;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (pch) {
|
|
/* Found it - return the name */
|
|
return import_name;
|
|
}
|
|
}
|
|
import_data += 20;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
dl_funcptr _PyImport_FindSharedFuncptrWindows(const char *prefix,
|
|
const char *shortname,
|
|
PyObject *pathname, FILE *fp)
|
|
{
|
|
dl_funcptr p;
|
|
char funcname[258], *import_python;
|
|
|
|
_Py_CheckPython3();
|
|
|
|
#if USE_UNICODE_WCHAR_CACHE
|
|
const wchar_t *wpathname = _PyUnicode_AsUnicode(pathname);
|
|
#else /* USE_UNICODE_WCHAR_CACHE */
|
|
wchar_t *wpathname = PyUnicode_AsWideCharString(pathname, NULL);
|
|
#endif /* USE_UNICODE_WCHAR_CACHE */
|
|
if (wpathname == NULL)
|
|
return NULL;
|
|
|
|
PyOS_snprintf(funcname, sizeof(funcname), "%.20s_%.200s", prefix, shortname);
|
|
|
|
{
|
|
HINSTANCE hDLL = NULL;
|
|
unsigned int old_mode;
|
|
|
|
/* Don't display a message box when Python can't load a DLL */
|
|
old_mode = SetErrorMode(SEM_FAILCRITICALERRORS);
|
|
|
|
/* bpo-36085: We use LoadLibraryEx with restricted search paths
|
|
to avoid DLL preloading attacks and enable use of the
|
|
AddDllDirectory function. We add SEARCH_DLL_LOAD_DIR to
|
|
ensure DLLs adjacent to the PYD are preferred. */
|
|
Py_BEGIN_ALLOW_THREADS
|
|
hDLL = LoadLibraryExW(wpathname, NULL,
|
|
LOAD_LIBRARY_SEARCH_DEFAULT_DIRS |
|
|
LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR);
|
|
Py_END_ALLOW_THREADS
|
|
#if !USE_UNICODE_WCHAR_CACHE
|
|
PyMem_Free(wpathname);
|
|
#endif /* USE_UNICODE_WCHAR_CACHE */
|
|
|
|
/* restore old error mode settings */
|
|
SetErrorMode(old_mode);
|
|
|
|
if (hDLL==NULL){
|
|
PyObject *message;
|
|
unsigned int errorCode;
|
|
|
|
/* Get an error string from Win32 error code */
|
|
wchar_t theInfo[256]; /* Pointer to error text
|
|
from system */
|
|
int theLength; /* Length of error text */
|
|
|
|
errorCode = GetLastError();
|
|
|
|
theLength = FormatMessageW(
|
|
FORMAT_MESSAGE_FROM_SYSTEM |
|
|
FORMAT_MESSAGE_IGNORE_INSERTS, /* flags */
|
|
NULL, /* message source */
|
|
errorCode, /* the message (error) ID */
|
|
MAKELANGID(LANG_NEUTRAL,
|
|
SUBLANG_DEFAULT),
|
|
/* Default language */
|
|
theInfo, /* the buffer */
|
|
sizeof(theInfo) / sizeof(wchar_t), /* size in wchars */
|
|
NULL); /* no additional format args. */
|
|
|
|
/* Problem: could not get the error message.
|
|
This should not happen if called correctly. */
|
|
if (theLength == 0) {
|
|
message = PyUnicode_FromFormat(
|
|
"DLL load failed with error code %u while importing %s",
|
|
errorCode, shortname);
|
|
} else {
|
|
/* For some reason a \r\n
|
|
is appended to the text */
|
|
if (theLength >= 2 &&
|
|
theInfo[theLength-2] == '\r' &&
|
|
theInfo[theLength-1] == '\n') {
|
|
theLength -= 2;
|
|
theInfo[theLength] = '\0';
|
|
}
|
|
message = PyUnicode_FromFormat(
|
|
"DLL load failed while importing %s: ", shortname);
|
|
|
|
PyUnicode_AppendAndDel(&message,
|
|
PyUnicode_FromWideChar(
|
|
theInfo,
|
|
theLength));
|
|
}
|
|
if (message != NULL) {
|
|
PyObject *shortname_obj = PyUnicode_FromString(shortname);
|
|
PyErr_SetImportError(message, shortname_obj, pathname);
|
|
Py_XDECREF(shortname_obj);
|
|
Py_DECREF(message);
|
|
}
|
|
return NULL;
|
|
} else {
|
|
char buffer[256];
|
|
|
|
PyOS_snprintf(buffer, sizeof(buffer),
|
|
#ifdef _DEBUG
|
|
"python%d%d_d.dll",
|
|
#else
|
|
"python%d%d.dll",
|
|
#endif
|
|
PY_MAJOR_VERSION,PY_MINOR_VERSION);
|
|
import_python = GetPythonImport(hDLL);
|
|
|
|
if (import_python &&
|
|
_stricmp(buffer,import_python)) {
|
|
PyErr_Format(PyExc_ImportError,
|
|
"Module use of %.150s conflicts "
|
|
"with this version of Python.",
|
|
import_python);
|
|
Py_BEGIN_ALLOW_THREADS
|
|
FreeLibrary(hDLL);
|
|
Py_END_ALLOW_THREADS
|
|
return NULL;
|
|
}
|
|
}
|
|
Py_BEGIN_ALLOW_THREADS
|
|
p = GetProcAddress(hDLL, funcname);
|
|
Py_END_ALLOW_THREADS
|
|
}
|
|
|
|
return p;
|
|
}
|