bool CryptFileDevice::seek(qint64 pos)
{
bool result = QIODevice::seek(pos);
if (m_encrypted)
{
m_device->seek(kHeaderLength + pos);
initCtr(&m_ctrState, m_ctrState.ivec);
}
else
{
m_device->seek(pos);
}
return result;
}
bool CryptFileDevice::initCipher()
{
const EVP_CIPHER *cipher = EVP_enc_null();
if (m_aesKeyLength == kAesKeyLength128)
cipher = EVP_aes_128_ctr();
else if (m_aesKeyLength == kAesKeyLength192)
cipher = EVP_aes_192_ctr();
else if (m_aesKeyLength == kAesKeyLength256)
cipher = EVP_aes_256_ctr();
else
Q_ASSERT_X(false, Q_FUNC_INFO, "Unknown value of AesKeyLength");
EVP_CIPHER_CTX ctx;
EVP_CIPHER_CTX_init(&ctx);
EVP_EncryptInit_ex(&ctx, cipher, NULL, NULL, NULL);
int keyLength = EVP_CIPHER_CTX_key_length(&ctx);
int ivLength = EVP_CIPHER_CTX_iv_length(&ctx);
unsigned char key[keyLength];
unsigned char iv[ivLength];
int ok = EVP_BytesToKey(cipher,
EVP_sha256(),
m_salt.isEmpty() ? NULL : (unsigned char *)m_salt.data(),
(unsigned char *)m_password.data(),
m_password.length(),
m_numRounds,
key,
iv);
EVP_CIPHER_CTX_cleanup(&ctx);
if (ok == 0)
return false;
int res = AES_set_encrypt_key(key, keyLength * 8, &m_aesKey);
if (res != 0)
return false;
initCtr(&m_ctrState, iv);
return true;
}
PerfMeasurement::PerfMeasurement(PerfMeasurement::EventMask toMeasure)
: impl(OffTheBooks::new_<Impl>()),
eventsMeasured(impl ? static_cast<Impl*>(impl)->init(toMeasure)
: EventMask(0)),
cpu_cycles(initCtr(CPU_CYCLES)),
instructions(initCtr(INSTRUCTIONS)),
cache_references(initCtr(CACHE_REFERENCES)),
cache_misses(initCtr(CACHE_MISSES)),
branch_instructions(initCtr(BRANCH_INSTRUCTIONS)),
branch_misses(initCtr(BRANCH_MISSES)),
bus_cycles(initCtr(BUS_CYCLES)),
page_faults(initCtr(PAGE_FAULTS)),
major_page_faults(initCtr(MAJOR_PAGE_FAULTS)),
context_switches(initCtr(CONTEXT_SWITCHES)),
cpu_migrations(initCtr(CPU_MIGRATIONS))
{
}
