| 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 |
#ifdef HAVE_CONFIG_H |
| 30 |
#include <config.h> |
| 31 |
#endif |
| 32 |
|
| 33 |
#include <windows.h> |
| 34 |
#include <stdio.h> |
| 35 |
#include <stdlib.h> |
| 36 |
#include <sys/stat.h> |
| 37 |
#include <string.h> |
| 38 |
#include <ctype.h> |
| 39 |
#include <direct.h> |
| 40 |
|
| 41 |
#include "openpgp.h" |
| 42 |
#include "wptW32API.h" |
| 43 |
#include "wptErrors.h" |
| 44 |
#include "wptTypes.h" |
| 45 |
#include "wptCrypto.h" |
| 46 |
|
| 47 |
#ifdef _MSC_VER |
| 48 |
typedef unsigned __int64 DDWORD; |
| 49 |
#else |
| 50 |
typedef unsigned long long DDWORD; |
| 51 |
#endif |
| 52 |
|
| 53 |
typedef struct { |
| 54 |
HANDLE fd; |
| 55 |
DDWORD filesize; |
| 56 |
DDWORD offset; |
| 57 |
BYTE *buffer; |
| 58 |
DWORD buffsize; |
| 59 |
const char *name; |
| 60 |
int n_passes; |
| 61 |
} wipe_context_s; |
| 62 |
|
| 63 |
struct arcfour_s { |
| 64 |
BYTE *seed; |
| 65 |
int pos; |
| 66 |
BYTE sbox[256]; |
| 67 |
DWORD i; |
| 68 |
DWORD j; |
| 69 |
}; |
| 70 |
|
| 71 |
|
| 72 |
void (*progress_cb) (void *, DDWORD, DDWORD); |
| 73 |
static void *progress_cb_value = NULL; |
| 74 |
|
| 75 |
void (*unlink_cb)(void *, const char *, int, int, int) = NULL; |
| 76 |
static void *unlink_cb_value = NULL; |
| 77 |
|
| 78 |
static int init_done = 0; |
| 79 |
static struct arcfour_s rnd; |
| 80 |
|
| 81 |
|
| 82 |
/* Add the random from buffer @buf with the length @buf_len |
| 83 |
into the seed @seed. The seed length (256) used to |
| 84 |
emulate a circular movment. */ |
| 85 |
static void |
| 86 |
add_random (unsigned char *seed, int *seed_pos, |
| 87 |
unsigned char *buf, int buf_len) |
| 88 |
{ |
| 89 |
int i, s_pos = *seed_pos; |
| 90 |
|
| 91 |
for (i=0; i < buf_len; i++) |
| 92 |
seed[(s_pos++ % 256)] ^= buf[i]; |
| 93 |
*seed_pos = s_pos % 256; |
| 94 |
} |
| 95 |
|
| 96 |
|
| 97 |
/* Enumerate all child windows. Store their text, their thread ID, |
| 98 |
their placement and their dimension. */ |
| 99 |
static BOOL CALLBACK |
| 100 |
child_proc (HWND h, LPARAM l) |
| 101 |
{ |
| 102 |
struct arcfour_s *cb = (struct arcfour_s*)l; |
| 103 |
DWORD a = (DWORD)h; |
| 104 |
WINDOWPLACEMENT p; |
| 105 |
RECT r; |
| 106 |
char buf[256]; |
| 107 |
int n; |
| 108 |
|
| 109 |
n = GetWindowText (h, buf, 255); |
| 110 |
if (n > 0) |
| 111 |
add_random (cb->seed, &cb->pos, (BYTE*)buf, n); |
| 112 |
add_random (cb->seed, &cb->pos, (BYTE*)&a, 4); |
| 113 |
a = GetWindowThreadProcessId (h, NULL); |
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add_random (cb->seed, &cb->pos, (BYTE*)&a, 4); |
| 115 |
GetWindowPlacement (h, &p); |
| 116 |
add_random (cb->seed, &cb->pos, (BYTE*)&p, sizeof (p)); |
| 117 |
GetWindowRect (h, &r); |
| 118 |
add_random (cb->seed, &cb->pos, (BYTE*)&r, sizeof (r)); |
| 119 |
return TRUE; |
| 120 |
} |
| 121 |
|
| 122 |
|
| 123 |
/* Initialize the seed with all kind of system variables. */ |
| 124 |
static void |
| 125 |
init_random (unsigned char *seed) |
| 126 |
{ |
| 127 |
int pos=0; |
| 128 |
DWORD buf[16]; |
| 129 |
int i=0; |
| 130 |
|
| 131 |
buf[i++] = (DWORD)GetActiveWindow (); |
| 132 |
buf[i++] = (DWORD)GetCapture (); |
| 133 |
buf[i++] = (DWORD)GetClipboardOwner (); |
| 134 |
buf[i++] = (DWORD)GetClipboardViewer (); |
| 135 |
buf[i++] = (DWORD)GetCurrentProcess (); |
| 136 |
buf[i++] = (DWORD)GetCurrentProcessId (); |
| 137 |
buf[i++] = (DWORD)GetCurrentThread (); |
| 138 |
buf[i++] = (DWORD)GetDesktopWindow (); |
| 139 |
buf[i++] = (DWORD)GetFocus (); |
| 140 |
buf[i++] = (DWORD)GetMessagePos (); |
| 141 |
buf[i++] = (DWORD)GetOpenClipboardWindow (); |
| 142 |
buf[i++] = (DWORD)GetProcessHeap (); |
| 143 |
buf[i++] = (DWORD)GetProcessWindowStation (); |
| 144 |
buf[i++] = (DWORD)GetQueueStatus (QS_ALLEVENTS); |
| 145 |
buf[i] = (DWORD)GetTickCount (); |
| 146 |
add_random (seed, &pos, (BYTE*)buf, 4*i); |
| 147 |
|
| 148 |
{ |
| 149 |
POINT p; |
| 150 |
GetCursorPos (&p); |
| 151 |
add_random (seed, &pos, (BYTE*)&p, sizeof (p)); |
| 152 |
GetCaretPos (&p); |
| 153 |
add_random (seed, &pos, (BYTE*)&p, sizeof (p)); |
| 154 |
} |
| 155 |
|
| 156 |
{ |
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STARTUPINFO inf; |
| 158 |
inf.cb = sizeof (inf); |
| 159 |
GetStartupInfo (&inf); |
| 160 |
add_random (seed, &pos, (BYTE*)&inf, sizeof (inf)); |
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} |
| 162 |
|
| 163 |
{ |
| 164 |
MEMORYSTATUS st; |
| 165 |
|
| 166 |
st.dwLength = sizeof (st); |
| 167 |
GlobalMemoryStatus (&st); |
| 168 |
add_random (seed, &pos, (BYTE*)&st, sizeof (st)); |
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} |
| 170 |
|
| 171 |
{ |
| 172 |
LARGE_INTEGER in; |
| 173 |
|
| 174 |
QueryPerformanceFrequency (&in); |
| 175 |
add_random (seed, &pos, (BYTE*)&in, sizeof (in)); |
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QueryPerformanceCounter (&in); |
| 177 |
add_random (seed, &pos, (BYTE*)&in, sizeof (in)); |
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} |
| 179 |
{ |
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rnd.seed = seed; |
| 181 |
rnd.pos = pos; |
| 182 |
EnumChildWindows (GetDesktopWindow (), child_proc, (LPARAM)&rnd); |
| 183 |
} |
| 184 |
|
| 185 |
} |
| 186 |
|
| 187 |
|
| 188 |
/* Initialize cipher with the seed as the key. */ |
| 189 |
static void |
| 190 |
init_arcfour (struct arcfour_s *ctx, BYTE *key) |
| 191 |
{ |
| 192 |
BYTE t; |
| 193 |
|
| 194 |
ctx->i = 0; |
| 195 |
ctx->j = 0; |
| 196 |
for (ctx->i=0; ctx->i < 256; ctx->i++) |
| 197 |
ctx->sbox[ctx->i] = (BYTE)ctx->i; |
| 198 |
for (ctx->i=0; ctx->i < 256; ctx->i++) { |
| 199 |
ctx->j += (ctx->j+ctx->sbox[ctx->i]+key[ctx->i]); |
| 200 |
ctx->j &= 255; |
| 201 |
t = ctx->sbox[ctx->i]; |
| 202 |
ctx->sbox[ctx->i] = ctx->sbox[ctx->j]; |
| 203 |
ctx->sbox[ctx->j] = t; |
| 204 |
} |
| 205 |
} |
| 206 |
|
| 207 |
|
| 208 |
/* Generate a single random byte. If the cipher is not |
| 209 |
init, do an init first. */ |
| 210 |
static BYTE |
| 211 |
rnd_byte (void) |
| 212 |
{ |
| 213 |
struct arcfour_s *ctx = &rnd; |
| 214 |
BYTE t; |
| 215 |
|
| 216 |
if (!init_done) { |
| 217 |
BYTE buf[256]; |
| 218 |
init_random (buf); |
| 219 |
init_arcfour (ctx, buf); |
| 220 |
init_done = 1; |
| 221 |
} |
| 222 |
|
| 223 |
ctx->i++; ctx->i &= 255; |
| 224 |
ctx->j += ctx->sbox[ctx->i]; ctx->j &= 255; |
| 225 |
t = ctx->sbox[ctx->i]; |
| 226 |
ctx->sbox[ctx->i] = ctx->sbox[ctx->j]; |
| 227 |
ctx->sbox[ctx->j] = t; |
| 228 |
return ctx->sbox[(ctx->sbox[ctx->i] + ctx->sbox[ctx->j]) & 255]; |
| 229 |
} |
| 230 |
|
| 231 |
|
| 232 |
/* Generate a single alpha-num charactor. */ |
| 233 |
static char |
| 234 |
random_char (void) |
| 235 |
{ |
| 236 |
byte c = 0; |
| 237 |
|
| 238 |
while (!isalnum(c)) |
| 239 |
c = rnd_byte (); |
| 240 |
return c % 127; |
| 241 |
} |
| 242 |
|
| 243 |
|
| 244 |
/* Use the file handle in the context to overwrite a file |
| 245 |
with prepared buffer contents. */ |
| 246 |
static void |
| 247 |
overwrite (wipe_context_s *ctx) |
| 248 |
{ |
| 249 |
DDWORD blocks = 0, mod = 0; |
| 250 |
DWORD nwritten = 0; |
| 251 |
LONG size_high = 0; |
| 252 |
|
| 253 |
blocks = ctx->filesize / ctx->buffsize; |
| 254 |
mod = ctx->filesize % ctx->buffsize; |
| 255 |
SetFilePointer (ctx->fd, 0, &size_high, FILE_BEGIN); |
| 256 |
while (blocks--) { |
| 257 |
if (!WriteFile (ctx->fd, ctx->buffer, ctx->buffsize, &nwritten, NULL)) |
| 258 |
break; |
| 259 |
ctx->offset += nwritten; |
| 260 |
if (unlink_cb) |
| 261 |
unlink_cb (unlink_cb_value, ctx->name, 0, (unsigned)ctx->offset, |
| 262 |
(unsigned)ctx->filesize*ctx->n_passes); |
| 263 |
} |
| 264 |
if (mod) { |
| 265 |
WriteFile (ctx->fd, ctx->buffer, (DWORD)mod, &nwritten, NULL); |
| 266 |
ctx->offset += nwritten; |
| 267 |
if (unlink_cb) |
| 268 |
unlink_cb (unlink_cb_value, ctx->name, 0, (unsigned)ctx->offset, |
| 269 |
(unsigned)ctx->filesize*ctx->n_passes); |
| 270 |
} |
| 271 |
FlushFileBuffers (ctx->fd); |
| 272 |
SetFilePointer (ctx->fd, 0, &size_high, FILE_BEGIN); |
| 273 |
} |
| 274 |
|
| 275 |
|
| 276 |
/* fill the buffer with random of the given level. */ |
| 277 |
static void |
| 278 |
randomize_buffer (byte *buf, size_t bufsize) |
| 279 |
{ |
| 280 |
const int blocksize = 512; |
| 281 |
int blocks = bufsize / blocksize; |
| 282 |
int mod = bufsize % blocksize; |
| 283 |
int i; |
| 284 |
|
| 285 |
while (blocks--) { |
| 286 |
for (i=0; i < blocksize; i++) |
| 287 |
buf[i] = rnd_byte (); |
| 288 |
buf += blocksize; |
| 289 |
} |
| 290 |
for (i=0; i < mod; i++) |
| 291 |
buf[i] = rnd_byte (); |
| 292 |
} |
| 293 |
|
| 294 |
|
| 295 |
/* performs a random overwrite. */ |
| 296 |
static void |
| 297 |
overwrite_random (int npasses, wipe_context_s * ctx) |
| 298 |
{ |
| 299 |
int i; |
| 300 |
|
| 301 |
for (i = 0; i < npasses; i++) { |
| 302 |
randomize_buffer (ctx->buffer, ctx->buffsize); |
| 303 |
overwrite (ctx); |
| 304 |
} |
| 305 |
} |
| 306 |
|
| 307 |
|
| 308 |
/* perform an overwrite with a specific byte (like 0x00). */ |
| 309 |
static void |
| 310 |
overwrite_byte (int byte, wipe_context_s * ctx) |
| 311 |
{ |
| 312 |
memset (ctx->buffer, byte, ctx->buffsize); |
| 313 |
overwrite (ctx); |
| 314 |
} /* overwrite_byte */ |
| 315 |
|
| 316 |
|
| 317 |
/* perform an overwrite with a specific byte triple (like 0x00, 0xFF, 0xAA). */ |
| 318 |
static void |
| 319 |
overwrite_bytes (int byte1, int byte2, int byte3, wipe_context_s * ctx) |
| 320 |
{ |
| 321 |
DWORD i; |
| 322 |
|
| 323 |
memset (ctx->buffer, byte1, ctx->buffsize); |
| 324 |
for (i = 1; i < ctx->buffsize; i += 3) { |
| 325 |
ctx->buffer[i] = byte2; |
| 326 |
ctx->buffer[i+1] = byte3; |
| 327 |
} |
| 328 |
overwrite (ctx); |
| 329 |
} /* overwrite_bytes */ |
| 330 |
|
| 331 |
|
| 332 |
/* For the case the file is not a regular file (this is true for |
| 333 |
devices or directories) this function tries to rename the file |
| 334 |
to random pattern and then it will be delete (without random!). */ |
| 335 |
extern "C" int |
| 336 |
rename_unlink (const char *path) |
| 337 |
{ |
| 338 |
struct stat statbuf; |
| 339 |
char *new_name = NULL, *p = NULL, c; |
| 340 |
int i = 0, rc = 0; |
| 341 |
int is_dir = 0; |
| 342 |
|
| 343 |
if (GetFileAttributes (path) & FILE_ATTRIBUTE_DIRECTORY) |
| 344 |
is_dir = 1; |
| 345 |
|
| 346 |
new_name = new char[strlen (path)+15]; |
| 347 |
if (!new_name) |
| 348 |
BUG (0); |
| 349 |
|
| 350 |
strcpy (new_name, path); |
| 351 |
p = strrchr (new_name, '\\'); |
| 352 |
if (p != NULL) { |
| 353 |
p++; |
| 354 |
*p = '\0'; |
| 355 |
} |
| 356 |
else |
| 357 |
p = new_name; |
| 358 |
do { |
| 359 |
while (i < 14) { |
| 360 |
c = random_char (); |
| 361 |
*p = c; |
| 362 |
p++; |
| 363 |
i++; |
| 364 |
} |
| 365 |
*p = '\0'; |
| 366 |
} while (stat (new_name, &statbuf) == 0); |
| 367 |
|
| 368 |
if (rename (path, new_name) == -1) { |
| 369 |
rc = WPTERR_FILE_READ; |
| 370 |
goto leave; |
| 371 |
} |
| 372 |
if (is_dir && RemoveDirectory (new_name) == FALSE) |
| 373 |
rc = WPTERR_FILE_REMOVE; |
| 374 |
else if (!DeleteFile (new_name)) |
| 375 |
rc = WPTERR_FILE_REMOVE; |
| 376 |
|
| 377 |
leave: |
| 378 |
free_if_alloc (new_name); |
| 379 |
return rc; |
| 380 |
} |
| 381 |
|
| 382 |
|
| 383 |
/* return the filesize as an 64-bit integer. */ |
| 384 |
static DDWORD |
| 385 |
GetFileSize64 (const char * path) |
| 386 |
{ |
| 387 |
FILE *fp = fopen (path, "r"); |
| 388 |
if (fp) { |
| 389 |
struct _stati64 statbuf; |
| 390 |
if (_fstati64 (fileno (fp), &statbuf) == -1) |
| 391 |
return (DDWORD)-1; |
| 392 |
fclose (fp); |
| 393 |
return statbuf.st_size; |
| 394 |
} |
| 395 |
return (DDWORD)-1; |
| 396 |
} |
| 397 |
|
| 398 |
|
| 399 |
static int |
| 400 |
_secure_unlink (const char * path, int mode, HANDLE *r_fd) |
| 401 |
{ |
| 402 |
wipe_context_s ctx; |
| 403 |
LONG size_high = 0; |
| 404 |
|
| 405 |
if (GetFileAttributes (path) & FILE_ATTRIBUTE_DIRECTORY) |
| 406 |
return rename_unlink (path); |
| 407 |
|
| 408 |
memset (&ctx, 0, sizeof (ctx)); |
| 409 |
ctx.name = path; |
| 410 |
ctx.buffsize = 16384; |
| 411 |
ctx.buffer = new byte[ctx.buffsize]; |
| 412 |
if (!ctx.buffer) |
| 413 |
BUG (0); |
| 414 |
|
| 415 |
ctx.filesize = GetFileSize64 (path); |
| 416 |
if (!ctx.filesize) { |
| 417 |
free_if_alloc (ctx.buffer); |
| 418 |
unlink (path); |
| 419 |
return 0; |
| 420 |
} |
| 421 |
|
| 422 |
ctx.fd = CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, |
| 423 |
OPEN_ALWAYS, 0, NULL); |
| 424 |
if (ctx.fd == INVALID_HANDLE_VALUE) { |
| 425 |
free_if_alloc (ctx.buffer); |
| 426 |
return WPTERR_FILE_OPEN; |
| 427 |
} |
| 428 |
else if (r_fd) |
| 429 |
*r_fd = ctx.fd; |
| 430 |
|
| 431 |
if (unlink_cb) |
| 432 |
unlink_cb (unlink_cb_value, ctx.name, 0, 0, 0); |
| 433 |
|
| 434 |
switch (mode) { |
| 435 |
case WIPE_MODE_FAST: |
| 436 |
ctx.n_passes = 1; |
| 437 |
overwrite_random (1, &ctx); |
| 438 |
break; |
| 439 |
|
| 440 |
case WIPE_MODE_SIMPLE: |
| 441 |
ctx.n_passes = 2; |
| 442 |
overwrite_random (2, &ctx); |
| 443 |
break; |
| 444 |
|
| 445 |
case WIPE_MODE_DOD: |
| 446 |
ctx.n_passes = 5; |
| 447 |
overwrite_random (1, &ctx); |
| 448 |
overwrite_byte ((~1) & 0xFF, &ctx); |
| 449 |
overwrite_random (1, &ctx); |
| 450 |
overwrite_byte ((~4) & 0xFF, &ctx); |
| 451 |
overwrite_random (1, &ctx); |
| 452 |
break; |
| 453 |
|
| 454 |
case WIPE_MODE_GUTMANN: |
| 455 |
ctx.n_passes = 39; |
| 456 |
overwrite_random (4, &ctx); |
| 457 |
overwrite_byte( 0x55, &ctx ); |
| 458 |
overwrite_byte ( 0xAA, &ctx ); |
| 459 |
overwrite_bytes( 0x92, 0x49, 0x24, &ctx ); |
| 460 |
overwrite_bytes( 0x49, 0x24, 0x92, &ctx ); |
| 461 |
overwrite_bytes( 0x24, 0x92, 0x49, &ctx ); |
| 462 |
overwrite_byte( 0x00, &ctx ); |
| 463 |
overwrite_byte( 0x11, &ctx ); |
| 464 |
overwrite_byte( 0x22, &ctx ); |
| 465 |
overwrite_byte( 0x33, &ctx ); |
| 466 |
overwrite_byte( 0x44, &ctx ); |
| 467 |
overwrite_byte( 0x55, &ctx ); |
| 468 |
overwrite_byte( 0x66, &ctx ); |
| 469 |
overwrite_byte( 0x77, &ctx ); |
| 470 |
overwrite_byte( 0x88, &ctx ); |
| 471 |
overwrite_byte( 0x99, &ctx ); |
| 472 |
overwrite_byte( 0xAA, &ctx ); |
| 473 |
overwrite_byte( 0xBB, &ctx ); |
| 474 |
overwrite_byte( 0xCC, &ctx ); |
| 475 |
overwrite_byte( 0xDD, &ctx ); |
| 476 |
overwrite_byte( 0xEE, &ctx ); |
| 477 |
overwrite_byte( 0xFF, &ctx ); |
| 478 |
overwrite_bytes( 0x92, 0x49, 0x24, &ctx ); |
| 479 |
overwrite_bytes( 0x49, 0x24, 0x92, &ctx ); |
| 480 |
overwrite_bytes( 0x24, 0x92, 0x49, &ctx ); |
| 481 |
overwrite_bytes( 0x6D, 0xB6, 0xDB, &ctx ); |
| 482 |
overwrite_bytes( 0xB6, 0xDB, 0x6D, &ctx ); |
| 483 |
overwrite_bytes( 0xDB, 0x6D, 0xB6, &ctx ); |
| 484 |
overwrite_random( 4, &ctx ); |
| 485 |
break; |
| 486 |
} |
| 487 |
|
| 488 |
/* Set file length to zero so allocated clusters cannot be trailed */ |
| 489 |
SetFilePointer (ctx.fd, 0, &size_high, FILE_BEGIN); |
| 490 |
SetEndOfFile (ctx.fd); |
| 491 |
CloseHandle (ctx.fd); |
| 492 |
|
| 493 |
memset (ctx.buffer, 0, ctx.buffsize); /* burn the last evidence */ |
| 494 |
free_if_alloc (ctx.buffer); |
| 495 |
|
| 496 |
return rename_unlink (path); |
| 497 |
} |
| 498 |
|
| 499 |
|
| 500 |
/* Delete a file in a secure way with the given mode @mode. */ |
| 501 |
extern "C" int |
| 502 |
secure_unlink (const char *path, int mode) |
| 503 |
{ |
| 504 |
/* If the file has one of the following attributes, the |
| 505 |
chance the file really gets overwritten is very low so |
| 506 |
we just to an unlink to spare time and entropy. */ |
| 507 |
DWORD attr = GetFileAttributes (path); |
| 508 |
if ((attr & FILE_ATTRIBUTE_COMPRESSED) || |
| 509 |
(attr & FILE_ATTRIBUTE_ENCRYPTED) || |
| 510 |
(attr & FILE_ATTRIBUTE_SPARSE_FILE)) |
| 511 |
return DeleteFile (path); /* XXX */ |
| 512 |
return _secure_unlink (path, mode, NULL); |
| 513 |
} |
| 514 |
|
| 515 |
|
| 516 |
/* Set the callback @cb for the wipe function. The callback is call every time |
| 517 |
the wipe function writes data to the file. */ |
| 518 |
extern "C" void |
| 519 |
secure_unlink_set_cb (void (*cb)(void *, const char *, int, int, int), |
| 520 |
void *cb_value) |
| 521 |
{ |
| 522 |
unlink_cb = cb; |
| 523 |
unlink_cb_value = cb_value; |
| 524 |
} |
| 525 |
|
| 526 |
|
| 527 |
/* wipe all free space of the given drive by creating a temp file |
| 528 |
which has the size of the free space. This file will be then |
| 529 |
overwritten with random and static pattern. */ |
| 530 |
extern "C" int |
| 531 |
wipe_freespace (const char * drive, HANDLE *r_fd, |
| 532 |
void (*cb)(void *, DDWORD, DDWORD), void * cb_value) |
| 533 |
{ |
| 534 |
ULARGE_INTEGER caller, total, frees; |
| 535 |
LONG hpart=0; |
| 536 |
HANDLE fd; |
| 537 |
int disktyp = GetDriveType (drive); |
| 538 |
int rc; |
| 539 |
char * file; |
| 540 |
|
| 541 |
if (disktyp != DRIVE_FIXED && disktyp != DRIVE_REMOVABLE) |
| 542 |
return -1; |
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if (!GetDiskFreeSpaceEx (drive, &caller, &total, &frees)) |
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return -1; |
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|
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/* disk is full */ |
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if (!frees.LowPart) |
| 548 |
return 0; |
| 549 |
file = new char[strlen (drive)+8]; |
| 550 |
if (!file) |
| 551 |
BUG (0); |
| 552 |
sprintf (file, "%stemp_winpt.tmp", drive); |
| 553 |
fd = CreateFile (file, |
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GENERIC_READ|GENERIC_WRITE, |
| 555 |
FILE_SHARE_READ|FILE_SHARE_WRITE, |
| 556 |
NULL, CREATE_ALWAYS, 0, NULL); |
| 557 |
if (fd == INVALID_HANDLE_VALUE) { |
| 558 |
free_if_alloc (file); |
| 559 |
return WPTERR_FILE_OPEN; |
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} |
| 561 |
hpart = frees.HighPart; |
| 562 |
SetFilePointer (fd, frees.LowPart, &hpart, FILE_BEGIN); |
| 563 |
SetEndOfFile (fd); |
| 564 |
CloseHandle (fd); |
| 565 |
|
| 566 |
if (cb && cb_value) { |
| 567 |
progress_cb = cb; |
| 568 |
progress_cb_value = cb_value; |
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} |
| 570 |
rc = _secure_unlink (file, WIPE_MODE_FAST, r_fd); |
| 571 |
free_if_alloc (file); |
| 572 |
return rc; |
| 573 |
} |
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