/* Returns TRUE iff x would result in NullKey or DeleteKey when encrypted with
FileKey. FALSE otherwise */
static int BogusKey(RPC2_EncryptionKey x)
{
RPC2_EncryptionKey temp;
int nul, del;
rpc2_Encrypt((char *)x, (char *)temp, RPC2_KEYSIZE, FileKey, RPC2_XOR);
nul = secure_compare(temp, RPC2_KEYSIZE, NullKey, RPC2_KEYSIZE);
del = secure_compare(temp, RPC2_KEYSIZE, DeleteKey, RPC2_KEYSIZE);
if (nul | del)
return TRUE;
else
return FALSE;
}
/* Returns TRUE iff viceId corr to a deleted Vice user(==> key of all 1's) */
static int IsADeletedUser(int viceId)
{
if (viceId < 0 || viceId >= PWLen)
return (FALSE);
if (secure_compare(PWArray[viceId], RPC2_KEYSIZE, DeleteKey, RPC2_KEYSIZE))
return TRUE;
return FALSE;
}
/**
* \brief Determine if two curve points are equal.
*
* \param p The first curve point.
* \param q The second curve point.
*
* \return Returns true if \a p and \a q are equal; false otherwise.
*/
bool Ed25519::equal(const Point &p, const Point &q)
{
limb_t a[NUM_LIMBS_256BIT];
limb_t b[NUM_LIMBS_256BIT];
bool result = true;
Curve25519::mul(a, p.x, q.z);
Curve25519::mul(b, q.x, p.z);
result &= secure_compare(a, b, sizeof(a));
Curve25519::mul(a, p.y, q.z);
Curve25519::mul(b, q.y, p.z);
result &= secure_compare(a, b, sizeof(a));
clean(a);
clean(b);
return result;
}
/* The C implementation of secure compare, don't use!
*
* The return type is a Fixnum to avoid certain optimizations that cause the
* branch predictor to potentially leak timing information.
*
* @param [String] rb_str_a
* @param [String] rb_str_b
* @return [Fixnum] Zero for success, other values for failure.
* @api private
*/
VALUE oroku_saki_secure_compare(VALUE rb_module, VALUE rb_str_a, VALUE rb_str_b) {
raise_unless_string(rb_str_a, "OrokuSaki.secure_compare");
raise_unless_string(rb_str_b, "OrokuSaki.secure_compare");
if (RSTRING_LEN(rb_str_a) != RSTRING_LEN(rb_str_b)) {
return INT2FIX(-1);
}
return INT2FIX(secure_compare(rb_str_a, rb_str_b));
}
bool Acorn128::checkTag(const void *tag, size_t len)
{
// Can never match if the expected tag length is too long.
if (len > 16)
return false;
// Compute the authentication tag and check it.
uint8_t temp[16];
computeTag(temp, len);
bool equal = secure_compare(temp, tag, len);
clean(temp);
return equal;
}
