/// <summary>
/// Copies the in-memory configuration to the stored configuration file.
/// </summary>
/// <param name="pin">The personal identification number (PIN) to use as an encryption key.</param>
public static void Save(int pin) => TSM.RunSafe(() =>
{
using (var s = Application.Context.OpenFileOutput(FILE_NAME, FileCreationMode.Private))
using (var w = new BinaryWriter(s))
{
w.Write(FILE_VERSION);
w.Write(Address);
w.Write(ConnectionTargets.Length);
foreach (var t in ConnectionTargets)
{
w.Write(t.Serialize());
}
w.Write(Contacts.Length);
foreach (var c in Contacts)
{
w.Write(c.Address);
w.WriteString472(c.Name);
}
w.Write(Recents.Length);
foreach (var r in Recents)
{
w.Write(r.Address);
w.Write(r.Timestamp.Ticks);
}
var aes = WinRTCrypto.SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithm.AesCbcPkcs7);
var sha = WinRTCrypto.HashAlgorithmProvider.OpenAlgorithm(HashAlgorithm.Sha512);
var bk = sha.HashData(BitConverter.GetBytes(pin));
using (var ms = new MemoryStream())
{
/*using (var es = new EncryptedStream(ms, key))
* using (var ws = new WrapperStream(ms))
* using (var cs = new CryptoStream(ws, WinRTCrypto.CryptographicEngine.CreateEncryptor(aes.CreateSymmetricKey(key)), CryptoStreamMode.Write))*/
using (var cw = new BinaryWriter(ms))
{
cw.Write(bk);
cw.Write(VerificationKeys.Length);
foreach (var k in VerificationKeys)
{
w.Write(k.Address);
w.Write(k.PrivateKey.Length);
w.Write(k.PrivateKey);
w.Write(k.PublicKey.Length);
w.Write(k.PublicKey);
}
}
var key = bk;
var data = ms.ToArray();
for (int i = 0; i < data.Length / 64 + 1; ++i)
{
key = sha.HashData(key);
for (int j = 0; j < 64 && (i < data.Length / 64 || j < data.Length % 64); ++j)
{
data[i * 64 + j] ^= key[j];
}
}
w.Write(data.Length);
w.Write(data);
}
}
});
/// <summary>
/// Resets the in-memory configuration.
/// </summary>
/// <param name="address">The address of the new configuration.</param>
public static void Reset(ErebusAddress address) => TSM.RunSafe(() =>
{
Address = address;
ConnectionTargets = new IConnectionTarget[0];
Contacts = new Contact[0];
Recents = new RecentEntry[0];
VerificationKeys = new KeyPair[0];
});
/// <summary>
/// Resets the in-memory configuration and saves it to disk with the specified PIN.
/// </summary>
/// <param name="address">The address of the new configuration.</param>
/// <param name="pin">The personal identification number (PIN) to use as an encryption key.</param>
public static void Configure(ErebusAddress address, int pin) => TSM.RunSafe(() =>
{
Reset(address);
Save(pin);
});
/// <summary>
/// Reloads the in-memory configuration from the configuration file.
/// </summary>
/// <param name="pin">The personal identification number (PIN) to use as a decryption key.</param>
public static void Reload(int pin) => TSM.RunSafe(() =>
{
using (var s = Application.Context.OpenFileInput(FILE_NAME))
using (var r = new BinaryReader(s))
{
var v = r.ReadUInt16();
if (v != FILE_VERSION)
{
throw new InvalidDataException($"Config file had version {v}; expected {FILE_VERSION}.");
}
Address = r.ReadErebusAddress();
ConnectionTargets = new IConnectionTarget[r.ReadInt32()];
for (int i = 0; i < ConnectionTargets.Length; ++i)
{
var t = r.ReadByte();
switch (t)
{
case 0:
ConnectionTargets[i] = new TCPIPConnectionTarget(r.ReadString472(), r.ReadInt32());
break;
case 1:
ConnectionTargets[i] = new BluetoothConnectionTarget(r.ReadString472());
break;
default:
throw new InvalidDataException($"Config file had invalid connection target type {t}.");
}
}
Contacts = new Contact[r.ReadInt32()];
for (int i = 0; i < Contacts.Length; ++i)
{
Contacts[i] = new Contact(r.ReadString472(), r.ReadErebusAddress());
}
Recents = new RecentEntry[r.ReadInt32()];
for (int i = 0; i < Recents.Length; ++i)
{
Recents[i] = new RecentEntry(r.ReadErebusAddress(), new DateTime(r.ReadInt64()));
}
Log.RecordEvent(typeof(Configuration), "Attempting to decrypt encrypted portion of configuration file.", LogEntrySeverity.Info);
var aes = WinRTCrypto.SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithm.AesCbcPkcs7);
var sha = WinRTCrypto.HashAlgorithmProvider.OpenAlgorithm(HashAlgorithm.Sha512);
var bk = sha.HashData(BitConverter.GetBytes(pin));
var key = bk;
var data = r.ReadBytes(r.ReadInt32());
for (int i = 0; i < data.Length / 64 + 1; ++i)
{
key = sha.HashData(key);
for (int j = 0; j < 64 && (i < data.Length / 64 || j < data.Length % 64); ++j)
{
data[i * 64 + j] ^= key[j];
}
}
using (var ms = new MemoryStream(data))
/*using (var es = new EncryptedStream(ms, key))
* using (var ws = new WrapperStream(ms))
* using (var cs = new CryptoStream(ws, WinRTCrypto.CryptographicEngine.CreateDecryptor(aes.CreateSymmetricKey(key)), CryptoStreamMode.Read))*/
using (var cr = new BinaryReader(ms))
{
if (!bk.SequenceEqual(cr.ReadBytes(64)))
{
throw new InvalidDataException("Incorrect PIN.");
}
VerificationKeys = new KeyPair[cr.ReadInt32()];
for (int i = 0; i < VerificationKeys.Length; ++i)
{
VerificationKeys[i] = new KeyPair(cr.ReadErebusAddress(), cr.ReadBytes(cr.ReadInt32()), cr.ReadBytes(cr.ReadInt32()));
}
}
Log.RecordEvent(typeof(Configuration), "Decryption successful.", LogEntrySeverity.Info);
}
});