mirror of
				https://github.com/python/cpython.git
				synced 2025-11-02 22:51:25 +00:00 
			
		
		
		
	Based on patch by Victor Stinner. Add private C API function _PyUnicode_AsUnicode() which is similar to PyUnicode_AsUnicode(), but checks for null characters.
		
			
				
	
	
		
			309 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			309 lines
		
	
	
	
		
			10 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>
 | 
						|
 | 
						|
// "activation context" magic - see dl_nt.c...
 | 
						|
#if HAVE_SXS
 | 
						|
extern ULONG_PTR _Py_ActivateActCtx();
 | 
						|
void _Py_DeactivateActCtx(ULONG_PTR cookie);
 | 
						|
#endif
 | 
						|
 | 
						|
#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
 | 
						|
};
 | 
						|
 | 
						|
/* Case insensitive string compare, to avoid any dependencies on particular
 | 
						|
   C RTL implementations */
 | 
						|
 | 
						|
static int strcasecmp (const char *string1, const char *string2)
 | 
						|
{
 | 
						|
    int first, second;
 | 
						|
 | 
						|
    do {
 | 
						|
        first  = tolower(*string1);
 | 
						|
        second = tolower(*string2);
 | 
						|
        string1++;
 | 
						|
        string2++;
 | 
						|
    } while (first && first == second);
 | 
						|
 | 
						|
    return (first - second);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/* 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;
 | 
						|
    const wchar_t *wpathname;
 | 
						|
 | 
						|
#ifndef _DEBUG
 | 
						|
    _Py_CheckPython3();
 | 
						|
#endif
 | 
						|
 | 
						|
    wpathname = _PyUnicode_AsUnicode(pathname);
 | 
						|
    if (wpathname == NULL)
 | 
						|
        return NULL;
 | 
						|
 | 
						|
    PyOS_snprintf(funcname, sizeof(funcname), "%.20s_%.200s", prefix, shortname);
 | 
						|
 | 
						|
    {
 | 
						|
        HINSTANCE hDLL = NULL;
 | 
						|
        unsigned int old_mode;
 | 
						|
#if HAVE_SXS
 | 
						|
        ULONG_PTR cookie = 0;
 | 
						|
#endif
 | 
						|
 | 
						|
        /* Don't display a message box when Python can't load a DLL */
 | 
						|
        old_mode = SetErrorMode(SEM_FAILCRITICALERRORS);
 | 
						|
 | 
						|
#if HAVE_SXS
 | 
						|
        cookie = _Py_ActivateActCtx();
 | 
						|
#endif
 | 
						|
        /* We use LoadLibraryEx so Windows looks for dependent DLLs
 | 
						|
            in directory of pathname first. */
 | 
						|
        /* XXX This call doesn't exist in Windows CE */
 | 
						|
        hDLL = LoadLibraryExW(wpathname, NULL,
 | 
						|
                              LOAD_WITH_ALTERED_SEARCH_PATH);
 | 
						|
#if HAVE_SXS
 | 
						|
        _Py_DeactivateActCtx(cookie);
 | 
						|
#endif
 | 
						|
 | 
						|
        /* 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 %d",
 | 
						|
                    errorCode);
 | 
						|
            } 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_FromString(
 | 
						|
                    "DLL load failed: ");
 | 
						|
 | 
						|
                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 &&
 | 
						|
                strcasecmp(buffer,import_python)) {
 | 
						|
                PyErr_Format(PyExc_ImportError,
 | 
						|
                             "Module use of %.150s conflicts "
 | 
						|
                             "with this version of Python.",
 | 
						|
                             import_python);
 | 
						|
                FreeLibrary(hDLL);
 | 
						|
                return NULL;
 | 
						|
            }
 | 
						|
        }
 | 
						|
        p = GetProcAddress(hDLL, funcname);
 | 
						|
    }
 | 
						|
 | 
						|
    return p;
 | 
						|
}
 |