private bool Verify(int version, string privateMac, string privateHash,
SecureString passphrase, string keyTypeName, string encryptionName, string comment, byte[] publicBlob, byte[] privateBlob) {
byte[] macData;
using (MemoryStream macDataBuff = new MemoryStream()) {
if (version == 1) {
WriteMacData(macDataBuff, privateBlob);
}
else {
WriteMacData(macDataBuff, keyTypeName);
WriteMacData(macDataBuff, encryptionName);
WriteMacData(macDataBuff, comment);
WriteMacData(macDataBuff, publicBlob);
WriteMacData(macDataBuff, privateBlob);
}
macDataBuff.Close();
macData = macDataBuff.ToArray();
}
if (privateMac != null) {
var sha1 = new SHA1CryptoServiceProvider();
var a = Encoding.ASCII.GetBytes("putty-private-key-file-mac-key");
sha1.TransformBlock(a, 0, a.Length, null, 0);
//var b = Encoding.UTF8.GetBytes(passphrase);
//sha1.TransformFinalBlock(b, 0, b.Length);
sha1.HashBlock(passphrase, true);
var key = sha1.Hash;
sha1.Clear();
var hmacsha1 = new HMACSHA1(key);
byte[] hash = hmacsha1.ComputeHash(macData);
hmacsha1.Clear();
string mac = BinToHex(hash);
return mac == privateMac;
}
if (privateHash == null) return true;
var sha2 = new SHA1CryptoServiceProvider();
var hash2 = sha2.ComputeHash(macData);
sha2.Clear();
var mac2 = BinToHex(hash2);
return mac2 == privateHash;
}
private static byte[] PuTTYPassphraseToKey(SecureString passphrase) {
const int HASH_SIZE = 20;
SHA1CryptoServiceProvider sha1 = new SHA1CryptoServiceProvider();
//byte[] pp = Encoding.UTF8.GetBytes(passphrase);
byte[] buf = new byte[HASH_SIZE * 2];
sha1.TransformBlock(new byte[] { 0, 0, 0, 0 }, 0, 4, null, 0);
sha1.HashBlock(passphrase, true);
//sha1.TransformFinalBlock(pp, 0, pp.Length);
Buffer.BlockCopy(sha1.Hash, 0, buf, 0, HASH_SIZE);
sha1.Initialize();
sha1.TransformBlock(new byte[] { 0, 0, 0, 1 }, 0, 4, null, 0);
sha1.HashBlock(passphrase, true);
//sha1.TransformFinalBlock(pp, 0, pp.Length);
Buffer.BlockCopy(sha1.Hash, 0, buf, HASH_SIZE, HASH_SIZE);
sha1.Clear();
byte[] key = new byte[32];
Buffer.BlockCopy(buf, 0, key, 0, key.Length);
return key;
}
