public void Challenge003()
{
var buffer = Buffer.FromHex("1b37373331363f78151b7f2b783431333d78397828372d363c78373e783a393b3736");
var scored = buffer.EnglishScore();
scored.Text.ShouldBe("Cooking MC's like a pound of bacon");
}
public void Challenge001()
{
var fromHex = Buffer.FromHex("49276d206b696c6c696e6720796f757220627261696e206c696b65206120706f69736f6e6f7573206d757368726f6f6d");
var toBase64 = fromHex.ToBase64();
toBase64.ShouldBe("SSdtIGtpbGxpbmcgeW91ciBicmFpbiBsaWtlIGEgcG9pc29ub3VzIG11c2hyb29t");
}
public void Challenge005()
{
const string toEncrypt = "Burning 'em, if you ain't quick and nimble\n" + "I go crazy when I hear a cymbal";
var buffer = Buffer.FromText(toEncrypt) ^ "ICE";
var asHex = buffer.ToHex();
asHex.ShouldBe("0b3637272a2b2e63622c2e69692a23693a2a3c6324202d623d63343c2a26226324272765272" + "a282b2f20430a652e2c652a3124333a653e2b2027630c692b20283165286326302e27282f");
}
public void Challenge002()
{
var buffer1 = Buffer.FromHex("1c0111001f010100061a024b53535009181c");
var buffer2 = Buffer.FromHex("686974207468652062756c6c277320657965");
var xorBuffer = buffer1 ^ buffer2;
var hex = xorBuffer.ToHex();
hex.ShouldBe("746865206b696420646f6e277420706c6179");
}
public void Challenge007()
{
var lines = File.ReadAllLines(Path.Combine(_dataPath, "Set001Challenge007.txt"));
var content = string.Join("", lines);
var buffer = Buffer.FromBase64(content);
var outputBuffer = new byte[buffer.Length];
var aes = Aes.Create();
aes.Mode = CipherMode.ECB;
aes.BlockSize = 128;
aes.Key = Encoding.ASCII.GetBytes("YELLOW SUBMARINE");
aes.CreateDecryptor().TransformBlock(buffer, 0, buffer.Length, outputBuffer, 0);
var text = new Buffer(outputBuffer).ToText();
text.Split('\n')[0].ShouldBe("I'm back and I'm ringin' the bell ");
}
public void Challenge006()
{
var lines = File.ReadAllLines(Path.Combine(_dataPath, "Set001Challenge006.txt"));
var content = string.Join("", lines);
var buffer = Buffer.FromBase64(content);
var likelihoods =
Enumerable.Range(2, 40).Select(blocksize => new {
BlockSize = blocksize,
Likelihood =
Enumerable.Range(0, 10).Select(block => {
var buffer1 = buffer.GetBlock(blocksize, block * 2);
var buffer2 = buffer.GetBlock(blocksize, block * 2 + 1);
return(buffer1.NormalisedHammingDistance(buffer2));
}).Average()
})
.OrderBy(m => m.Likelihood);
var blockSize = likelihoods.First().BlockSize;
var transposed = buffer.Select((value, index) => new { Value = value, Index = index })
.GroupBy(x => x.Index % blockSize)
.Select(grp => grp.Select(x => x.Value).ToArray())
.Select(m => new Buffer(m))
.Select(m => m.EnglishScore())
.Select(score => Convert.ToChar(score.Byte))
.ToArray();
var key = new string(transposed);
var message = (buffer ^ key).ToText();
blockSize.ShouldBe(29);
key.ShouldBe("Terminator X: Bring the noise");
message.Split('\n')[0].ShouldBe("I'm back and I'm ringin' the bell ");
}
public void Challenge006_HammingDistance()
{
Buffer.FromText("this is a test").HammingDistance(Buffer.FromText("wokka wokka!!!")).ShouldBe(37);
}
