public void Compute_Balanced_Sha256d()
{
var hasher = SHA256.Create();
var nodes = new byte[][]
{
/* A */ hasher.ComputeHash(Encoding.UTF8.GetBytes("La ciudad y los perros")),
/* B */ hasher.ComputeHash(Encoding.UTF8.GetBytes("Conversación en La Catedral")),
/* C */ hasher.ComputeHash(Encoding.UTF8.GetBytes("Pantaleón y las visitadoras")),
/* D */ hasher.ComputeHash(Encoding.UTF8.GetBytes("La tía Julia y el Escribidor"))
};
// Manual computing
// levels = 2; ceil(log2(4))
// 3th level, 4 nodes, without balance
var hashA = hasher.ComputeHash(hasher.ComputeHash(nodes[0]));
var hashB = hasher.ComputeHash(hasher.ComputeHash(nodes[1]));
var hashC = hasher.ComputeHash(hasher.ComputeHash(nodes[2]));
var hashD = hasher.ComputeHash(hasher.ComputeHash(nodes[3]));
var hashA_B = TestUtils.Concat(hashA, hashB);
var hashC_D = TestUtils.Concat(hashC, hashD);
// 2th level, 2 nodes, without complement
hashA_B = hasher.ComputeHash(hasher.ComputeHash(hashA_B));
hashC_D = hasher.ComputeHash(hasher.ComputeHash(hashC_D));
var hashROOT = TestUtils.Concat(hashA_B, hashC_D);
// 1st level, 1 node, only hash
hashROOT = hasher.ComputeHash(hasher.ComputeHash(hashROOT));
// Computing map:
// ROOT
// +-----+-----+
// A_B C_D
// +--+--+ +--+--+
// A B C D
var tree = new HashTree();
tree.HashRecipe.Add(CryptoHashName.Sha256);
tree.HashRecipe.Add(CryptoHashName.Sha256);
tree.Nodes.AddRange(nodes);
tree.ComputeRoot();
Assert.IsTrue(TestUtils.AreEqual(hashROOT, tree.Root));
System.Diagnostics.Debug.WriteLine("Time: {0}ms", tree.LastComputeEllapsed);
}
public void Compute_Unbalanced_Sha256d()
{
var hasher = SHA256.Create();
var nodes = new byte[][]
{
/* A */ hasher.ComputeHash(Encoding.UTF8.GetBytes("La ciudad y los perros")),
/* B */ hasher.ComputeHash(Encoding.UTF8.GetBytes("La Casa Verde")),
/* C */ hasher.ComputeHash(Encoding.UTF8.GetBytes("Conversación en La Catedral")),
/* D */ hasher.ComputeHash(Encoding.UTF8.GetBytes("Pantaleón y las visitadoras")),
/* E */ hasher.ComputeHash(Encoding.UTF8.GetBytes("La tía Julia y el Escribidor"))
};
// Manual computing
// levels = 3; ceil(log2(5))
// 4th level, 5 nodes, need balance: rigth (3)
var hashA = hasher.ComputeHash(hasher.ComputeHash(nodes[0]));
var hashB = hasher.ComputeHash(hasher.ComputeHash(nodes[1]));
var hashC = hasher.ComputeHash(hasher.ComputeHash(nodes[2]));
var hashD = hasher.ComputeHash(hasher.ComputeHash(nodes[3]));
var hashE = hasher.ComputeHash(hasher.ComputeHash(nodes[4]));
var hashX4 = hasher.ComputeHash(hasher.ComputeHash(hashA)); // balance
var hashA_B = TestUtils.Concat(hashA, hashB);
var hashC_D = TestUtils.Concat(hashC, hashD);
var hashE_X4 = TestUtils.Concat(hashE, hashX4);
// 3th level, 3 nodes, need balance: left (2)
hashA_B = hasher.ComputeHash(hasher.ComputeHash(hashA_B));
hashC_D = hasher.ComputeHash(hasher.ComputeHash(hashC_D));
hashE_X4 = hasher.ComputeHash(hasher.ComputeHash(hashE_X4));
var hashX3 = hasher.ComputeHash(hasher.ComputeHash(hashE_X4)); // balance
var hashX3_A_B = TestUtils.Concat(hashX3, hashA_B);
var hashC_D_E_X4 = TestUtils.Concat(hashC_D, hashE_X4);
// 2nd level, 2 nodes, without balance
hashX3_A_B = hasher.ComputeHash(hasher.ComputeHash(hashX3_A_B));
hashC_D_E_X4 = hasher.ComputeHash(hasher.ComputeHash(hashC_D_E_X4));
var hashROOT = TestUtils.Concat(hashX3_A_B, hashC_D_E_X4);
// 1st level, 1 node, only hash
hashROOT = hasher.ComputeHash(hasher.ComputeHash(hashROOT));
// Computing map:
// ROOT
// +-----------+-----------+
// X3_A_B C_D_E_X4
// +-----+-----+ +-----+-----+
// (X3) E_X4' A_B C_D E_X4
// +--+--+ +--+--+ +--+--+
// A B C D E A' (X4)
var tree = new HashTree();
tree.HashRecipe.Add(CryptoHashName.Sha256);
tree.HashRecipe.Add(CryptoHashName.Sha256);
tree.Nodes.AddRange(nodes);
tree.ComputeRoot();
Assert.IsTrue(TestUtils.AreEqual(hashROOT, tree.Root));
System.Diagnostics.Debug.WriteLine("Time: {0}ms", tree.LastComputeEllapsed);
}