public void Test_fcontract()
{
long [] input = new long[] {
0x0000000001212121,
0x0000000000484848,
0x0000000000242424,
0x0000000001090909,
0x0000000000848484,
0x0000000001212121,
0x0000000000909090,
0x0000000000242424,
0x0000000002121212,
0x0000000000848484
};
byte[] output = new byte[32];
Curve25519Donna.fcontract(output, input);
byte[] expected_key = new byte[] {
0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21,
0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21
};
for (int i = 0; i < 32; i++)
{
Assert.AreEqual <long>(expected_key[i], output[i]);
}
}
public void Test_fexpand()
{
long [] output = new long[19];
byte[] input_key = new byte[] {
0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21,
0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21
};
Curve25519Donna.fexpand(output, input_key);
long[] expected = new long[] {
0x0000000001212121,
0x0000000000484848,
0x0000000000242424,
0x0000000001090909,
0x0000000000848484,
0x0000000001212121,
0x0000000000909090,
0x0000000000242424,
0x0000000002121212,
0x0000000000848484
};
for (int i = 0; i < 10; i++)
{
Assert.AreEqual <long>(expected[i], output[i]);
}
}
public void Test_s32_eq()
{
int same = Curve25519Donna.s32_eq(11, 11);
int different = Curve25519Donna.s32_eq(13, 32);
Assert.AreEqual <int>(0, different);
Assert.AreEqual <int>(-1, same); //0xFFFFFFFF
}
public void Test_s32_gte()
{
int bigger = Curve25519Donna.s32_gte(3, 2);
int same = Curve25519Donna.s32_gte(5000, 5000);
int less = Curve25519Donna.s32_gte(4999, 10001);
Assert.AreEqual <int>(-1, bigger);
Assert.AreEqual <int>(-1, same);
Assert.AreEqual <int>(0, less);
}
public void Test_swap_conditional()
{
long[] incrementing = new long[19];
for (int i = 0; i < 19; i++)
{
incrementing[i] = i + 1;
}
long[] decrementing = new long[19];
int j = 19;
for (int i = 0; i < 19; i++)
{
decrementing[i] = j;
j--;
}
long[] inc = (long[])incrementing.Clone();
long[] dec = (long[])decrementing.Clone();
//First-run, don't swap (iswap = 0)
Curve25519Donna.swap_conditional(inc, dec, 0);
for (int i = 0; i < 10; i++)
{
Assert.AreEqual <long>(i + 1, inc[i]);
}
j = 19;
for (int i = 0; i < 10; i++)
{
Assert.AreEqual <long>(j, dec[i]);
j--;
}
//Now swap (iswap = 1)
Curve25519Donna.swap_conditional(inc, dec, 1);
//First 10 places of each should have swapped, making this nicely symmetrical output
long [] inc_expected = new long[] {
19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19
};
long[] dec_expected = new long[] {
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
};
for (int i = 0; i < 19; i++)
{
Assert.AreEqual <long>(inc_expected[i], inc[i]);
}
for (int i = 0; i < 19; i++)
{
Assert.AreEqual <long>(dec_expected[i], dec[i]);
}
}
public override byte[] calculateAgreement(byte[] ourPrivate, byte[] theirPublic)
{
byte[] sharedKeyAgreement = new byte[32];
Curve25519Donna.curve25519_donna(sharedKeyAgreement, ourPrivate, theirPublic);
return(sharedKeyAgreement);
}
public override byte[] generatePublicKey(byte[] privateKey)
{
byte[] publicKey = new byte[32];
Curve25519Donna.curve25519_donna(publicKey, privateKey, basepoint);
return(publicKey);
}
