trunk/PTD/wptWipeFile.cpp

/* wptWipeFile.cpp - Secure file removal
 *      Copyright (C) 2001-2005 Timo Schulz
 *      Copyright (C) 2000 Matt Gauthier
 *
 * WinPT 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.
 *
 * WinPT 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 WinPT; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 *
 **************************************************************************
 * This code based on the sunlink.c file from the SRM project, but        *
 * it was heavily modified to work with W32 and with added GCRYPT         *
 * support for gathering random bytes.                                    *
 *                                                                        *
 * The original code was placed under the GNU Lesser Public License,      *
 * even so I decide to put this file under the GNU General Public License.*
 **************************************************************************
 */

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <string.h>
#include <ctype.h>
#include <direct.h>

#include "openpgp.h"
#include "wptW32API.h"
#include "wptErrors.h"
#include "wptTypes.h"


typedef unsigned __int64 DDWORD;

typedef struct {
    HANDLE fd;
    DDWORD filesize;
    DDWORD offset;
    BYTE  *buffer;
    DWORD  buffsize;
    const char *name;
    int    n_passes;
} wipe_context_s;


void (*progress_cb) (void *, DDWORD, DDWORD);
static void *progress_cb_value = NULL;

void (*unlink_cb)(void *, const char *, int, int, int) = NULL;
static void *unlink_cb_value = NULL;

/* Use the file handle in the context to overwrite a file
   with prepared buffer contents. */
static void 
overwrite (wipe_context_s *ctx)
{
    DDWORD blocks = 0, mod = 0;
    DWORD nwritten = 0;
    LONG size_high = 0;

    blocks = ctx->filesize / ctx->buffsize;
    mod = ctx->filesize % ctx->buffsize;
    SetFilePointer (ctx->fd, 0, &size_high, FILE_BEGIN);
    while (blocks--) {
        if (!WriteFile (ctx->fd, ctx->buffer, ctx->buffsize, &nwritten, NULL))
            break;
        ctx->offset += nwritten;
        if (unlink_cb)
            unlink_cb (unlink_cb_value, ctx->name, 0, (unsigned)ctx->offset, 
                       (unsigned)ctx->filesize*ctx->n_passes);
    }
    if (mod) {
        WriteFile (ctx->fd, ctx->buffer, (DWORD)mod, &nwritten, NULL);
        ctx->offset += nwritten;
        if (unlink_cb)
            unlink_cb (unlink_cb_value, ctx->name, 0, (unsigned)ctx->offset, 
                       (unsigned)ctx->filesize*ctx->n_passes);
    }
    FlushFileBuffers (ctx->fd);
    SetFilePointer (ctx->fd, 0, &size_high, FILE_BEGIN);
}


/* fill the buffer with random of the given level. */
static void
randomize_buffer (byte *buf, size_t bufsize, int level)
{
    const int blocksize = 512;
    int blocks = bufsize / blocksize;
    int mod = bufsize % blocksize;
    
    while (blocks--) {
        gpg_randomize (buf, blocksize, level);
        buf += blocksize;
    }
    if (mod)
        gpg_randomize (buf, mod, level);
}


/* performs a random overwrite. */
static void
overwrite_random (int npasses, wipe_context_s * ctx) 
{       
    int i;
    
    for (i = 0; i < npasses; i++) {
        randomize_buffer (ctx->buffer, ctx->buffsize, 0);
        overwrite (ctx);
    }
}


/* perform an overwrite with a specific byte (like 0x00). */
static void 
overwrite_byte (int byte, wipe_context_s * ctx) 
{
    memset (ctx->buffer, byte, ctx->buffsize);
    overwrite (ctx);
} /* overwrite_byte */


/* perform an overwrite with a specific byte triple (like 0x00, 0xFF, 0xAA). */
static void
overwrite_bytes (int byte1, int byte2, int byte3, wipe_context_s * ctx)
{
    DWORD i;

    memset (ctx->buffer, byte1, ctx->buffsize);
    for (i = 1; i < ctx->buffsize; i += 3) {
        ctx->buffer[i] = byte2;
        ctx->buffer[i+1] = byte3;
    }
    overwrite (ctx);
} /* overwrite_bytes */


/* For the case the file is not a regular file (this is true for
   devices or directories) this function tries to rename the file
   to random pattern and then it will be delete (without random!). */
int 
rename_unlink (const char *path)
{
    struct stat statbuf;
    char *new_name = NULL, *p = NULL, c;  
    int i = 0, rc = 0;
    int is_dir = 0;

    if (GetFileAttributes (path) & FILE_ATTRIBUTE_DIRECTORY)
        is_dir = 1;
    
    new_name = new char[strlen (path)+15];
    if (!new_name)
        BUG (0);
    
    strcpy (new_name, path);
    p = strrchr (new_name, '\\');
    if (p != NULL) {
        p++;
        *p = '\0';
    } 
    else
        p = new_name;
    do {
        while (i < 14) {
            c = gpg_random_char (1);
            *p = c; 
            p++;
            i++;
        }
        *p = '\0';
    } while (stat (new_name, &statbuf) == 0);
    
    if (rename (path, new_name) == -1) {
        rc = WPTERR_FILE_READ;
        goto leave;
    }
    if (is_dir && RemoveDirectory (new_name) == FALSE)
        rc = WPTERR_FILE_REMOVE;
    else if (!DeleteFile (new_name))
        rc = WPTERR_FILE_REMOVE;
    
leave:
    free_if_alloc (new_name);
    return rc;
}


/* return the filesize as an 64-bit integer. */
static __int64
GetFileSize64 (const char * path)
{
    FILE *fp = fopen (path, "r");
    if (fp) {
        struct _stati64 statbuf;
        if (_fstati64 (fileno (fp), &statbuf) == -1)
            return -1;
        fclose (fp);
        return statbuf.st_size;
    }
    return -1;
}


static int
_secure_unlink (const char * path, int mode, HANDLE *r_fd)
{
    wipe_context_s ctx;
    LONG size_high = 0;
    
    if (GetFileAttributes (path) & FILE_ATTRIBUTE_DIRECTORY)
        return rename_unlink (path);
    
    memset (&ctx, 0, sizeof (ctx));
    ctx.name = path;
    ctx.buffsize = 16384;
    ctx.buffer = new byte[ctx.buffsize];
    if (!ctx.buffer)
        BUG (0);
    
    ctx.filesize = GetFileSize64 (path);
    if (!ctx.filesize) {
        free_if_alloc (ctx.buffer);
        unlink (path);
        return 0;
    }

    ctx.fd = CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL,
                         OPEN_ALWAYS, 0, NULL);
    if (ctx.fd == INVALID_HANDLE_VALUE) {
        free_if_alloc (ctx.buffer);
        return WPTERR_FILE_OPEN;
    }
    else if (r_fd)
        *r_fd = ctx.fd;
    
    gpg_quick_random_gen (1);
    if (unlink_cb)
        unlink_cb (unlink_cb_value, ctx.name, 0, 0, 0);

    switch (mode) {
    case WIPE_MODE_FAST:
        ctx.n_passes = 1;
        overwrite_random (1, &ctx);
        break;

    case WIPE_MODE_SIMPLE:
        ctx.n_passes = 2;
        overwrite_random (2, &ctx);
        break;
        
    case WIPE_MODE_DOD:
        ctx.n_passes = 5;
        overwrite_random (1, &ctx);
        overwrite_byte ((~1) & 0xFF, &ctx);
        overwrite_random (1, &ctx);
        overwrite_byte ((~4) & 0xFF, &ctx);
        overwrite_random (1, &ctx);
        break;
        
    case WIPE_MODE_GUTMANN:
        ctx.n_passes = 39;
        overwrite_random (4, &ctx);
        overwrite_byte( 0x55, &ctx );
        overwrite_byte ( 0xAA, &ctx );
        overwrite_bytes( 0x92, 0x49, 0x24, &ctx );
        overwrite_bytes( 0x49, 0x24, 0x92, &ctx );
        overwrite_bytes( 0x24, 0x92, 0x49, &ctx );
        overwrite_byte( 0x00, &ctx );
        overwrite_byte( 0x11, &ctx );
        overwrite_byte( 0x22, &ctx );
        overwrite_byte( 0x33, &ctx );
        overwrite_byte( 0x44, &ctx );
        overwrite_byte( 0x55, &ctx );
        overwrite_byte( 0x66, &ctx );
        overwrite_byte( 0x77, &ctx );
        overwrite_byte( 0x88, &ctx );
        overwrite_byte( 0x99, &ctx );
        overwrite_byte( 0xAA, &ctx );
        overwrite_byte( 0xBB, &ctx );
        overwrite_byte( 0xCC, &ctx );
        overwrite_byte( 0xDD, &ctx );
        overwrite_byte( 0xEE, &ctx );
        overwrite_byte( 0xFF, &ctx );
        overwrite_bytes( 0x92, 0x49, 0x24, &ctx );
        overwrite_bytes( 0x49, 0x24, 0x92, &ctx );
        overwrite_bytes( 0x24, 0x92, 0x49, &ctx );
        overwrite_bytes( 0x6D, 0xB6, 0xDB, &ctx );
        overwrite_bytes( 0xB6, 0xDB, 0x6D, &ctx );
        overwrite_bytes( 0xDB, 0x6D, 0xB6, &ctx );
        overwrite_random( 4, &ctx );
        break;
    }
        
    /* Set file length to zero so allocated clusters cannot be trailed */       
    SetFilePointer (ctx.fd, 0, &size_high, FILE_BEGIN);
    SetEndOfFile (ctx.fd);
    CloseHandle (ctx.fd);
    
    memset (ctx.buffer, 0, ctx.buffsize); /* burn the last evidence */  
    free_if_alloc (ctx.buffer);

    return rename_unlink (path);
}


/* Delete a file in a secure way with the given mode. */
int 
secure_unlink (const char *path, int mode)
{
    return _secure_unlink (path, mode, NULL);
}


/* Set the callback @cb for the wipe function. The callback is call every time
   the wipe function writes data to the file. */
void
secure_unlink_set_cb (void (*cb)(void *, const char *, int, int, int), 
                      void *cb_value)
{
    unlink_cb = cb;
    unlink_cb_value = cb_value;
}


/* wipe all free space of the given drive by creating a temp file
   which has the size of the free space. This file will be then
   overwritten with random and static pattern. */
int
wipe_freespace (const char * drive, HANDLE *r_fd,
                void (*cb)(void *, DDWORD, DDWORD), void * cb_value)
{
    ULARGE_INTEGER caller, total, frees;
    LONG hpart=0;
    HANDLE fd;
    int disktyp = GetDriveType (drive);
    int rc;
    char * file;

    if (disktyp != DRIVE_FIXED && disktyp != DRIVE_REMOVABLE)
        return -1;
    if (!GetDiskFreeSpaceEx (drive, &caller, &total, &frees))
        return -1;   

    /* disk is full */
    if (!frees.LowPart)
        return 0;
    file = new char[strlen (drive)+8];
    if (!file)
        BUG (0);
    sprintf (file, "%stemp_winpt.tmp", drive);
    fd = CreateFile (file,
                    GENERIC_READ|GENERIC_WRITE,
                    FILE_SHARE_READ|FILE_SHARE_WRITE,
                    NULL, CREATE_ALWAYS, 0, NULL);
    if (fd == INVALID_HANDLE_VALUE) {
        free_if_alloc (file);
        return WPTERR_FILE_OPEN;
    }
    hpart = frees.HighPart;
    SetFilePointer (fd, frees.LowPart, &hpart, FILE_BEGIN);
    SetEndOfFile (fd);
    CloseHandle (fd);

    if (cb && cb_value) {
        progress_cb = cb;
        progress_cb_value = cb_value;
    }
    rc = _secure_unlink (file, WIPE_MODE_FAST, r_fd);
    free_if_alloc (file);
    return rc;
}
1	/* wptWipeFile.cpp - Secure file removal
2	* Copyright (C) 2001-2005 Timo Schulz
3	* Copyright (C) 2000 Matt Gauthier
4	*
5	* WinPT software; you can redistribute it and/or modify
6	* it under the terms of the GNU General Public License as published by
7	* the Free Software Foundation; either version 2 of the License, or
8	* (at your option) any later version.
9	*
10	* WinPT is distributed in the hope that it will be useful,
11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13	* GNU General Public License for more details.
14	*
15	* You should have received a copy of the GNU General Public License
16	* along with WinPT; if not, write to the Free Software
17	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
18	*
19	**************************************************************************
20	* This code based on the sunlink.c file from the SRM project, but *
21	* it was heavily modified to work with W32 and with added GCRYPT *
22	* support for gathering random bytes. *
23	* *
24	* The original code was placed under the GNU Lesser Public License, *
25	* even so I decide to put this file under the GNU General Public License.*
26	**************************************************************************
27	*/
28
29	#include <windows.h>
30	#include <stdio.h>
31	#include <stdlib.h>
32	#include <sys/stat.h>
33	#include <string.h>
34	#include <ctype.h>
35	#include <direct.h>
36
37	#include "openpgp.h"
38	#include "wptW32API.h"
39	#include "wptErrors.h"
40	#include "wptTypes.h"
41
42
43	typedef unsigned __int64 DDWORD;
44
45	typedef struct {
46	HANDLE fd;
47	DDWORD filesize;
48	DDWORD offset;
49	BYTE *buffer;
50	DWORD buffsize;
51	const char *name;
52	int n_passes;
53	} wipe_context_s;
54
55
56	void (progress_cb) (void , DDWORD, DDWORD);
57	static void *progress_cb_value = NULL;
58
59	void (unlink_cb)(void , const char *, int, int, int) = NULL;
60	static void *unlink_cb_value = NULL;
61
62	/* Use the file handle in the context to overwrite a file
63	with prepared buffer contents. */
64	static void
65	overwrite (wipe_context_s *ctx)
66	{
67	DDWORD blocks = 0, mod = 0;
68	DWORD nwritten = 0;
69	LONG size_high = 0;
70
71	blocks = ctx->filesize / ctx->buffsize;
72	mod = ctx->filesize % ctx->buffsize;
73	SetFilePointer (ctx->fd, 0, &size_high, FILE_BEGIN);
74	while (blocks--) {
75	if (!WriteFile (ctx->fd, ctx->buffer, ctx->buffsize, &nwritten, NULL))
76	break;
77	ctx->offset += nwritten;
78	if (unlink_cb)
79	unlink_cb (unlink_cb_value, ctx->name, 0, (unsigned)ctx->offset,
80	(unsigned)ctx->filesize*ctx->n_passes);
81	}
82	if (mod) {
83	WriteFile (ctx->fd, ctx->buffer, (DWORD)mod, &nwritten, NULL);
84	ctx->offset += nwritten;
85	if (unlink_cb)
86	unlink_cb (unlink_cb_value, ctx->name, 0, (unsigned)ctx->offset,
87	(unsigned)ctx->filesize*ctx->n_passes);
88	}
89	FlushFileBuffers (ctx->fd);
90	SetFilePointer (ctx->fd, 0, &size_high, FILE_BEGIN);
91	}
92
93
94	/* fill the buffer with random of the given level. */
95	static void
96	randomize_buffer (byte *buf, size_t bufsize, int level)
97	{
98	const int blocksize = 512;
99	int blocks = bufsize / blocksize;
100	int mod = bufsize % blocksize;
101
102	while (blocks--) {
103	gpg_randomize (buf, blocksize, level);
104	buf += blocksize;
105	}
106	if (mod)
107	gpg_randomize (buf, mod, level);
108	}
109
110
111	/* performs a random overwrite. */
112	static void
113	overwrite_random (int npasses, wipe_context_s * ctx)
114	{
115	int i;
116
117	for (i = 0; i < npasses; i++) {
118	randomize_buffer (ctx->buffer, ctx->buffsize, 0);
119	overwrite (ctx);
120	}
121	}
122
123
124	/* perform an overwrite with a specific byte (like 0x00). */
125	static void
126	overwrite_byte (int byte, wipe_context_s * ctx)
127	{
128	memset (ctx->buffer, byte, ctx->buffsize);
129	overwrite (ctx);
130	} /* overwrite_byte */
131
132
133	/* perform an overwrite with a specific byte triple (like 0x00, 0xFF, 0xAA). */
134	static void
135	overwrite_bytes (int byte1, int byte2, int byte3, wipe_context_s * ctx)
136	{
137	DWORD i;
138
139	memset (ctx->buffer, byte1, ctx->buffsize);
140	for (i = 1; i < ctx->buffsize; i += 3) {
141	ctx->buffer[i] = byte2;
142	ctx->buffer[i+1] = byte3;
143	}
144	overwrite (ctx);
145	} /* overwrite_bytes */
146
147
148	/* For the case the file is not a regular file (this is true for
149	devices or directories) this function tries to rename the file
150	to random pattern and then it will be delete (without random!). */
151	int
152	rename_unlink (const char *path)
153	{
154	struct stat statbuf;
155	char new_name = NULL, p = NULL, c;
156	int i = 0, rc = 0;
157	int is_dir = 0;
158
159	if (GetFileAttributes (path) & FILE_ATTRIBUTE_DIRECTORY)
160	is_dir = 1;
161
162	new_name = new char[strlen (path)+15];
163	if (!new_name)
164	BUG (0);
165
166	strcpy (new_name, path);
167	p = strrchr (new_name, '\\');
168	if (p != NULL) {
169	p++;
170	*p = '\0';
171	}
172	else
173	p = new_name;
174	do {
175	while (i < 14) {
176	c = gpg_random_char (1);
177	*p = c;
178	p++;
179	i++;
180	}
181	*p = '\0';
182	} while (stat (new_name, &statbuf) == 0);
183
184	if (rename (path, new_name) == -1) {
185	rc = WPTERR_FILE_READ;
186	goto leave;
187	}
188	if (is_dir && RemoveDirectory (new_name) == FALSE)
189	rc = WPTERR_FILE_REMOVE;
190	else if (!DeleteFile (new_name))
191	rc = WPTERR_FILE_REMOVE;
192
193	leave:
194	free_if_alloc (new_name);
195	return rc;
196	}
197
198
199	/* return the filesize as an 64-bit integer. */
200	static __int64
201	GetFileSize64 (const char * path)
202	{
203	FILE *fp = fopen (path, "r");
204	if (fp) {
205	struct _stati64 statbuf;
206	if (_fstati64 (fileno (fp), &statbuf) == -1)
207	return -1;
208	fclose (fp);
209	return statbuf.st_size;
210	}
211	return -1;
212	}
213
214
215	static int
216	_secure_unlink (const char * path, int mode, HANDLE *r_fd)
217	{
218	wipe_context_s ctx;
219	LONG size_high = 0;
220
221	if (GetFileAttributes (path) & FILE_ATTRIBUTE_DIRECTORY)
222	return rename_unlink (path);
223
224	memset (&ctx, 0, sizeof (ctx));
225	ctx.name = path;
226	ctx.buffsize = 16384;
227	ctx.buffer = new byte[ctx.buffsize];
228	if (!ctx.buffer)
229	BUG (0);
230
231	ctx.filesize = GetFileSize64 (path);
232	if (!ctx.filesize) {
233	free_if_alloc (ctx.buffer);
234	unlink (path);
235	return 0;
236	}
237
238	ctx.fd = CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL,
239	OPEN_ALWAYS, 0, NULL);
240	if (ctx.fd == INVALID_HANDLE_VALUE) {
241	free_if_alloc (ctx.buffer);
242	return WPTERR_FILE_OPEN;
243	}
244	else if (r_fd)
245	*r_fd = ctx.fd;
246
247	gpg_quick_random_gen (1);
248	if (unlink_cb)
249	unlink_cb (unlink_cb_value, ctx.name, 0, 0, 0);
250
251	switch (mode) {
252	case WIPE_MODE_FAST:
253	ctx.n_passes = 1;
254	overwrite_random (1, &ctx);
255	break;
256
257	case WIPE_MODE_SIMPLE:
258	ctx.n_passes = 2;
259	overwrite_random (2, &ctx);
260	break;
261
262	case WIPE_MODE_DOD:
263	ctx.n_passes = 5;
264	overwrite_random (1, &ctx);
265	overwrite_byte ((~1) & 0xFF, &ctx);
266	overwrite_random (1, &ctx);
267	overwrite_byte ((~4) & 0xFF, &ctx);
268	overwrite_random (1, &ctx);
269	break;
270
271	case WIPE_MODE_GUTMANN:
272	ctx.n_passes = 39;
273	overwrite_random (4, &ctx);
274	overwrite_byte( 0x55, &ctx );
275	overwrite_byte ( 0xAA, &ctx );
276	overwrite_bytes( 0x92, 0x49, 0x24, &ctx );
277	overwrite_bytes( 0x49, 0x24, 0x92, &ctx );
278	overwrite_bytes( 0x24, 0x92, 0x49, &ctx );
279	overwrite_byte( 0x00, &ctx );
280	overwrite_byte( 0x11, &ctx );
281	overwrite_byte( 0x22, &ctx );
282	overwrite_byte( 0x33, &ctx );
283	overwrite_byte( 0x44, &ctx );
284	overwrite_byte( 0x55, &ctx );
285	overwrite_byte( 0x66, &ctx );
286	overwrite_byte( 0x77, &ctx );
287	overwrite_byte( 0x88, &ctx );
288	overwrite_byte( 0x99, &ctx );
289	overwrite_byte( 0xAA, &ctx );
290	overwrite_byte( 0xBB, &ctx );
291	overwrite_byte( 0xCC, &ctx );
292	overwrite_byte( 0xDD, &ctx );
293	overwrite_byte( 0xEE, &ctx );
294	overwrite_byte( 0xFF, &ctx );
295	overwrite_bytes( 0x92, 0x49, 0x24, &ctx );
296	overwrite_bytes( 0x49, 0x24, 0x92, &ctx );
297	overwrite_bytes( 0x24, 0x92, 0x49, &ctx );
298	overwrite_bytes( 0x6D, 0xB6, 0xDB, &ctx );
299	overwrite_bytes( 0xB6, 0xDB, 0x6D, &ctx );
300	overwrite_bytes( 0xDB, 0x6D, 0xB6, &ctx );
301	overwrite_random( 4, &ctx );
302	break;
303	}
304
305	/* Set file length to zero so allocated clusters cannot be trailed */
306	SetFilePointer (ctx.fd, 0, &size_high, FILE_BEGIN);
307	SetEndOfFile (ctx.fd);
308	CloseHandle (ctx.fd);
309
310	memset (ctx.buffer, 0, ctx.buffsize); /* burn the last evidence */
311	free_if_alloc (ctx.buffer);
312
313	return rename_unlink (path);
314	}
315
316
317	/* Delete a file in a secure way with the given mode. */
318	int
319	secure_unlink (const char *path, int mode)
320	{
321	return _secure_unlink (path, mode, NULL);
322	}
323
324
325	/* Set the callback @cb for the wipe function. The callback is call every time
326	the wipe function writes data to the file. */
327	void
328	secure_unlink_set_cb (void (cb)(void , const char *, int, int, int),
329	void *cb_value)
330	{
331	unlink_cb = cb;
332	unlink_cb_value = cb_value;
333	}
334
335
336	/* wipe all free space of the given drive by creating a temp file
337	which has the size of the free space. This file will be then
338	overwritten with random and static pattern. */
339	int
340	wipe_freespace (const char * drive, HANDLE *r_fd,
341	void (cb)(void , DDWORD, DDWORD), void * cb_value)
342	{
343	ULARGE_INTEGER caller, total, frees;
344	LONG hpart=0;
345	HANDLE fd;
346	int disktyp = GetDriveType (drive);
347	int rc;
348	char * file;
349
350	if (disktyp != DRIVE_FIXED && disktyp != DRIVE_REMOVABLE)
351	return -1;
352	if (!GetDiskFreeSpaceEx (drive, &caller, &total, &frees))
353	return -1;
354
355	/* disk is full */
356	if (!frees.LowPart)
357	return 0;
358	file = new char[strlen (drive)+8];
359	if (!file)
360	BUG (0);
361	sprintf (file, "%stemp_winpt.tmp", drive);
362	fd = CreateFile (file,
363	GENERIC_READ\|GENERIC_WRITE,
364	FILE_SHARE_READ\|FILE_SHARE_WRITE,
365	NULL, CREATE_ALWAYS, 0, NULL);
366	if (fd == INVALID_HANDLE_VALUE) {
367	free_if_alloc (file);
368	return WPTERR_FILE_OPEN;
369	}
370	hpart = frees.HighPart;
371	SetFilePointer (fd, frees.LowPart, &hpart, FILE_BEGIN);
372	SetEndOfFile (fd);
373	CloseHandle (fd);
374
375	if (cb && cb_value) {
376	progress_cb = cb;
377	progress_cb_value = cb_value;
378	}
379	rc = _secure_unlink (file, WIPE_MODE_FAST, r_fd);
380	free_if_alloc (file);
381	return rc;
382	}