size_t PWSfile::ReadCBC(unsigned char &type, unsigned char* &data,
size_t &length)
{
unsigned char *buffer = NULL;
size_t buffer_len = 0;
size_t retval;
ASSERT(m_fish != NULL && m_IV != NULL);
retval = _readcbc(m_fd, buffer, buffer_len, type,
m_fish, m_IV, m_terminal, m_fileLength);
if (buffer_len > 0) {
if (buffer_len < length || data == NULL)
length = buffer_len; // set to length read
// if buffer_len > length, data is truncated to length
// probably an error.
if (data != NULL) {
memcpy(data, buffer, length);
trashMemory(buffer, buffer_len);
delete[] buffer;
} else { // NULL data means pass buffer directly to caller
data = buffer; // caller must trash & delete[]!
}
} else {
// no need to delete[] buffer, since _readcbc will not allocate if
// buffer_len is zero
}
return retval;
}
size_t PWSfileV1V2::ReadCBC(unsigned char &type, StringX &data)
{
unsigned char *buffer = NULL;
size_t buffer_len = 0;
size_t retval;
ASSERT(m_fish != NULL && m_IV != NULL);
retval = _readcbc(m_fd, buffer, buffer_len, type,
m_fish, m_IV, m_terminal);
if (buffer_len > 0) {
wchar_t *wc = new wchar_t[buffer_len+1];
size_t wcLen = pws_os::mbstowcs(wc, buffer_len + 1,
reinterpret_cast<const char *>(buffer),
buffer_len, false);
ASSERT(wcLen != 0);
if (wcLen < buffer_len + 1)
wc[wcLen] = TCHAR('\0');
else
wc[buffer_len] = TCHAR('\0');
data = wc;
trashMemory(wc, wcLen);
delete[] wc;
trashMemory(buffer, buffer_len);
delete[] buffer;
} else {
data = _T("");
// no need to delete[] buffer, since _readcbc will not allocate if
// buffer_len is zero
}
return retval;
}
bool PWSfile::Decrypt(const stringT &fn, const StringX &passwd, stringT &errmess)
{
size_t len;
unsigned char* buf = NULL;
bool status = true;
unsigned char salt[SaltLength];
unsigned char ipthing[8];
unsigned char randstuff[StuffSize];
unsigned char randhash[SHA1::HASHLEN];
unsigned char temphash[SHA1::HASHLEN];
FILE *in = pws_os::FOpen(fn, _T("rb"));
if (in == NULL) {
status = false;
goto exit;
}
#ifdef KEEP_FILE_MODE_BWD_COMPAT
uint32 i32;
fread(&i32, 1, sizeof(uint32), in); // XXX portability issue
len = i32;
#else
fread(randstuff, 1, 8, in);
randstuff[8] = randstuff[9] = TCHAR('\0'); // ugly bug workaround
fread(randhash, 1, sizeof(randhash), in);
GenRandhash(passwd, randstuff, temphash);
if (memcmp(reinterpret_cast<char *>(randhash), reinterpret_cast<char *>(temphash), SHA1::HASHLEN) != 0) {
fclose(in);
LoadAString(errmess, IDSC_BADPASSWORD);
return false;
}
#endif // KEEP_FILE_MODE_BWD_COMPAT
{ // decryption in a block, since we use goto
fread(salt, 1, SaltLength, in);
fread(ipthing, 1, 8, in);
unsigned char dummyType;
unsigned char *pwd = NULL;
size_t passlen = 0;
long file_len = pws_os::fileLength(in);
ConvertString(passwd, pwd, passlen);
Fish *fish = BlowFish::MakeBlowFish(pwd, reinterpret_cast<int &>(passlen), salt, SaltLength);
trashMemory(pwd, passlen);
#ifdef UNICODE
delete[] pwd; // gross - ConvertString allocates only if UNICODE.
#endif
if (_readcbc(in, buf, len,dummyType, fish, ipthing, 0, file_len) == 0) {
delete fish;
delete[] buf; // if not yet allocated, delete[] NULL, which is OK
return false;
}
delete fish;
fclose(in);
} // decrypt
{ // write decrypted data
size_t suffix_len = CIPHERTEXT_SUFFIX.length();
size_t filepath_len = fn.length();
stringT out_fn = fn;
out_fn = out_fn.substr(0,filepath_len - suffix_len);
FILE *out = pws_os::FOpen(out_fn, _T("wb"));
if (out != NULL) {
size_t fret = fwrite(buf, 1, len, out);
if (fret != len) {
int save_errno = errno;
fclose(out);
errno = save_errno;
goto exit;
}
if (fclose(out) != 0) {
status = false;
goto exit;
}
} else { // open failed
status = false;
goto exit;
}
} // write decrypted
exit:
if (!status)
errmess = ErrorMessages();
delete[] buf; // allocated by _readcbc
return status;
}
bool PWSfile::Decrypt(const stringT &fn, const StringX &passwd, stringT &errmess)
{
ulong64 file_len;
size_t len;
unsigned char* buf = nullptr;
bool status = true;
unsigned char salt[SaltLength];
unsigned char ipthing[8];
unsigned char randstuff[StuffSize];
unsigned char randhash[SHA1::HASHLEN];
unsigned char temphash[SHA1::HASHLEN];
FILE *in = pws_os::FOpen(fn, _T("rb"));
if (in == nullptr) {
status = false;
goto exit;
}
file_len = pws_os::fileLength(in);
if (file_len < (8 + sizeof(randhash) + 8 + SaltLength)) {
fclose(in);
LoadAString(errmess, IDSC_FILE_TOO_SHORT);
return false;
}
fread(randstuff, 1, 8, in);
randstuff[8] = randstuff[9] = TCHAR('\0'); // ugly bug workaround
fread(randhash, 1, sizeof(randhash), in);
GenRandhash(passwd, randstuff, temphash);
if (memcmp(reinterpret_cast<char *>(randhash), reinterpret_cast<char *>(temphash), SHA1::HASHLEN) != 0) {
fclose(in);
LoadAString(errmess, IDSC_BADPASSWORD);
return false;
}
{ // decryption in a block, since we use goto
fread(salt, 1, SaltLength, in);
fread(ipthing, 1, 8, in);
unsigned char dummyType;
unsigned char *pwd = nullptr;
size_t passlen = 0;
ConvertPasskey(passwd, pwd, passlen);
Fish *fish = BlowFish::MakeBlowFish(pwd, reinterpret_cast<unsigned int &>(passlen), salt, SaltLength);
trashMemory(pwd, passlen);
delete[] pwd; // gross - ConvertPasskey allocates.
if (_readcbc(in, buf, len,dummyType, fish, ipthing, 0, file_len) == 0) {
delete fish;
delete[] buf; // if not yet allocated, delete[] nullptr, which is OK
return false;
}
delete fish;
fclose(in);
} // decrypt
{ // write decrypted data
size_t suffix_len = CIPHERTEXT_SUFFIX.length();
size_t filepath_len = fn.length();
stringT out_fn = fn;
out_fn = out_fn.substr(0,filepath_len - suffix_len);
FILE *out = pws_os::FOpen(out_fn, _T("wb"));
if (out != nullptr) {
size_t fret = fwrite(buf, 1, len, out);
if (fret != len) {
int save_errno = errno;
fclose(out);
errno = save_errno;
goto exit;
}
if (fclose(out) != 0) {
status = false;
goto exit;
}
} else { // open failed
status = false;
goto exit;
}
} // write decrypted
exit:
if (!status)
errmess = ErrorMessages();
delete[] buf; // allocated by _readcbc
return status;
}
