Problem - Kevin Tafuro

if (pattern_pass(fd, buf, sizeof(buf), st.st_size) = = -1) return -1;
}
for (pass = 0; pass < sizeof(triple_pats) / patternsz; pass++) {
pattern = triple_pats[pass];
count = sizeof(buf) / patternsz;
for (i = 0; i < count; i++)
memcpy(buf + (i * patternsz), pattern, patternsz);
if (pattern_pass(fd, buf, patternsz * count, st.st_size) = = -1) return -1;
}
for (pass = 0; pass < 4; pass++)
if (random_pass(fd, st.st_size) = = -1) return -1;
return 0;
}
int spc_file_wipe(FILE *f) {
return spc_fd_wipe(fileno(f));
}
The Unix implementations should work on Windows systems using the standard C
runtime API; however, it is rare that the standard C runtime API is used on Windows.
The following code implements SpcWipeFile( ), which is virtually identical to
the standard C version except that it uses only Win32 APIs for file access.
#include
#include
#define SPC_WIPE_BUFSIZE 4096
static BOOL RandomPass(HANDLE hFile, HCRYPTPROV hProvider, DWORD dwFileSize)
{
BYTE pbBuffer[SPC_WIPE_BUFSIZE];
DWORD cbBuffer, cbTotalWritten, cbWritten;
if (SetFilePointer(hFile, 0, 0, FILE_BEGIN) = = 0xFFFFFFFF) return FALSE;
while (dwFileSize > 0) {
cbBuffer = (dwFileSize > sizeof(pbBuffer) ? sizeof(pbBuffer) : dwFileSize);
if (!CryptGenRandom(hProvider, cbBuffer, pbBuffer)) return FALSE;
for (cbTotalWritten = 0; cbBuffer > 0; cbTotalWritten += cbWritten)
if (!WriteFile(hFile, pbBuffer + cbTotalWritten, cbBuffer - cbTotalWritten,
&cbWritten, 0)) return FALSE;
dwFileSize -= cbTotalWritten;
}
return TRUE;
}
static BOOL PatternPass(HANDLE hFile, BYTE *pbBuffer, DWORD cbBuffer, DWORD
dwFileSize) {
DWORD cbTotalWritten, cbWrite, cbWritten;
if (!cbBuffer || SetFilePointer(hFile, 0, 0, FILE_BEGIN) = = 0xFFFFFFFF) return
FALSE;
while (dwFileSize > 0) {
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Erasing Files Securely | 51