/// <summary>
/// Get this is a valid header file
/// </summary>
///
/// <param name="Authority">The stream containing a KeyAuthority structure</param>
///
/// <returns>Valid</returns>
public static bool IsValid(KeyAuthority Authority)
{
int count = 0;
for (int i = 0; i < Authority.OriginId.Length; i++)
{
if (Authority.OriginId[i] == (byte)0)
{
count++;
}
}
return(count < 8);
}
/// <summary>
/// A PackageKey header structure.
/// </summary>
///
/// <param name="Authority">The <see cref="KeyAuthority">KeyAuthority</see> structure containing the key authorization schema.</param>
/// <param name="Cipher">The <see cref="VTDev.Libraries.CEXEngine.Crypto.Common.CipherDescription">CipherDescription</see> structure containing a complete description of the cipher instance.</param>
/// <param name="SubKeyCount">The number of Key Sets contained in this key package file.</param>
///
/// <exception cref="CryptoProcessingException">Thrown if an invalid ExtensionKey is used</exception>
public PackageKey(KeyAuthority Authority, CipherDescription Cipher, int SubKeyCount)
{
this.KeyPolicy = Authority.KeyPolicy;
this.Authority = Authority;
this.Description = Cipher;
this.SubKeyCount = SubKeyCount;
SubKeyPolicy = new long[SubKeyCount];
SubKeyID = new byte[SubKeyCount][];
// generate the subkey ids and set master policy
for (int i = 0; i < SubKeyCount; i++)
{
SubKeyPolicy[i] = (long)Authority.KeyPolicy;
SubKeyID[i] = Guid.NewGuid().ToByteArray();
}
CreatedOn = DateTime.Now.Ticks;
}
/// <summary>
/// Compare this object instance with another
/// </summary>
///
/// <param name="Obj">Object to compare</param>
///
/// <returns>True if equal, otherwise false</returns>
public override bool Equals(Object Obj)
{
if (!(Obj is KeyAuthority))
{
return(false);
}
KeyAuthority other = (KeyAuthority)Obj;
if (!Compare.IsEqual(DomainId, other.DomainId))
{
return(false);
}
if (!Compare.IsEqual(OriginId, other.OriginId))
{
return(false);
}
if (!Compare.IsEqual(TargetId, other.TargetId))
{
return(false);
}
if (!Compare.IsEqual(PackageId, other.PackageId))
{
return(false);
}
if (!Compare.IsEqual(PackageTag, other.PackageTag))
{
return(false);
}
if (KeyPolicy != other.KeyPolicy)
{
return(false);
}
if (OptionFlag != other.OptionFlag)
{
return(false);
}
return(true);
}
/// <summary>
/// Initialize the PackageKey structure using a Stream
/// </summary>
///
/// <param name="KeyStream">The Stream containing the PackageKey</param>
public PackageKey(Stream KeyStream)
{
BinaryReader reader = new BinaryReader(KeyStream);
KeyPolicy = reader.ReadInt64();
CreatedOn = reader.ReadInt64();
Authority = new KeyAuthority(KeyStream);
Description = new CipherDescription(KeyStream);
SubKeyCount = reader.ReadInt32();
SubKeyPolicy = new long[SubKeyCount];
byte[] buffer = reader.ReadBytes(SubKeyCount * KEYPOL_SIZE);
Buffer.BlockCopy(buffer, 0, SubKeyPolicy, 0, buffer.Length);
buffer = reader.ReadBytes(SubKeyCount * KEYID_SIZE);
SubKeyID = new byte[SubKeyCount][];
for (int i = 0; i < SubKeyCount; i++)
{
SubKeyID[i] = new byte[KEYID_SIZE];
Buffer.BlockCopy(buffer, i * KEYID_SIZE, SubKeyID[i], 0, KEYID_SIZE);
}
}
/// <summary>
/// Set the KeyAuthority structure
/// </summary>
///
/// <param name="KeyStream">The stream containing a key package</param>
/// <param name="Authority">The CipherDescription structure</param>
public static void SetKeyAuthority(Stream KeyStream, KeyAuthority Authority)
{
KeyStream.Seek(KEYAUT_SEEK, SeekOrigin.Begin);
new BinaryWriter(KeyStream).Write(Authority.ToBytes());
}
/// <summary>
/// Initialize the PackageKey structure using a Stream
/// </summary>
///
/// <param name="KeyStream">The Stream containing the PackageKey</param>
public PackageKey(Stream KeyStream)
{
BinaryReader reader = new BinaryReader(KeyStream);
KeyPolicy = reader.ReadInt64();
CreatedOn = reader.ReadInt64();
Authority = new KeyAuthority(KeyStream);
Description = new CipherDescription(KeyStream);
ExtensionKey = reader.ReadBytes(EXTKEY_SIZE);
SubKeyCount = reader.ReadInt32();
SubKeyPolicy = new long[SubKeyCount];
byte[] buffer = reader.ReadBytes(SubKeyCount * KEYPOL_SIZE);
Buffer.BlockCopy(buffer, 0, SubKeyPolicy, 0, buffer.Length);
buffer = reader.ReadBytes(SubKeyCount * KEYID_SIZE);
SubKeyID = new byte[SubKeyCount][];
for (int i = 0; i < SubKeyCount; i++)
{
SubKeyID[i] = new byte[KEYID_SIZE];
Buffer.BlockCopy(buffer, i * KEYID_SIZE, SubKeyID[i], 0, KEYID_SIZE);
}
}
/// <summary>
/// Set the KeyAuthority structure
/// </summary>
///
/// <param name="KeyStream">The stream containing a key package</param>
/// <param name="Authority">The CipherDescription structure</param>
public static void SetKeyAuthority(Stream KeyStream, KeyAuthority Authority)
{
KeyStream.Seek(KEYAUT_SEEK, SeekOrigin.Begin);
new BinaryWriter(KeyStream).Write(Authority.ToBytes());
}
/// <summary>
/// A PackageKey header structure.
/// </summary>
///
/// <param name="Authority">The <see cref="KeyAuthority">KeyAuthority</see> structure containing the key authorization schema.</param>
/// <param name="Cipher">The <see cref="CipherDescription">CipherDescription</see> structure containing a complete description of the cipher instance.</param>
/// <param name="SubKeyCount">The number of Key Sets contained in this key package file.</param>
/// <param name="ExtensionKey">An array of random bytes used to encrypt a message file extension. A null value auto generates this field.</param>
///
/// <exception cref="CryptoProcessingException">Thrown if an invalid ExtensionKey is used</exception>
public PackageKey(KeyAuthority Authority, CipherDescription Cipher, int SubKeyCount, byte[] ExtensionKey = null)
{
this.KeyPolicy = Authority.KeyPolicy;
this.Authority = Authority;
this.Description = Cipher;
this.SubKeyCount = SubKeyCount;
SubKeyPolicy = new long[SubKeyCount];
SubKeyID = new byte[SubKeyCount][];
// generate the subkey ids and set master policy
for (int i = 0; i < SubKeyCount; i++)
{
SubKeyPolicy[i] = (long)Authority.KeyPolicy;
SubKeyID[i] = Guid.NewGuid().ToByteArray();
}
if (ExtensionKey != null)
{
if (ExtensionKey.Length != 16)
throw new CryptoProcessingException("PackageKey:CTor", "Extension key must be exactly 16 bytes in length!", new ArgumentOutOfRangeException());
this.ExtensionKey = ExtensionKey;
}
else
{
using (CSPRng rand = new CSPRng())
this.ExtensionKey = rand.GetBytes(16);
}
CreatedOn = DateTime.Now.Ticks;
}
/// <summary>
/// Create a key file using a <see cref="PackageKey"/> structure; containing the cipher description and operating ids and flags.
/// </summary>
///
/// <param name="Package">The <see cref="PackageKey">Key Header</see> containing the cipher description and operating ids and flags</param>
/// <param name="SeedEngine">The <see cref="Prngs">Random Generator</see> used to create the stage I seed material during key generation.</param>
/// <param name="DigestEngine">The <see cref="Digests">Digest Engine</see> used in the stage II phase of key generation.</param>
///
/// <exception cref="CryptoProcessingException">Thrown if a key file exists at the path specified, the path is read only, the CipherDescription or KeyAuthority structures are invalid, or
/// number of SubKeys specified is either less than 1 or more than the maximum allowed (100,000)</exception>
public void Create(PackageKey Package, Prngs SeedEngine = Prngs.CSPRng, Digests DigestEngine = Digests.SHA512)
{
// if you are getting exceptions.. read the docs!
if (File.Exists(_keyPath))
throw new CryptoProcessingException("PackageFactory:Create", "The key file exists! Can not overwrite an existing key file, choose a different path.", new FileLoadException());
if (!DirectoryTools.IsWritable(Path.GetDirectoryName(_keyPath)))
throw new CryptoProcessingException("PackageFactory:Create", "The selected directory is read only! Choose a different path.", new UnauthorizedAccessException());
if (!CipherDescription.IsValid(Package.Description))
throw new CryptoProcessingException("PackageFactory:Create", "The key package cipher settings are invalid!", new FormatException());
if (!KeyAuthority.IsValid(Package.Authority))
throw new CryptoProcessingException("PackageFactory:Create", "The key package key authority settings are invalid!", new FormatException());
if (Package.SubKeyCount < 1)
throw new CryptoProcessingException("PackageFactory:Create", "The key package must contain at least 1 key!", new ArgumentOutOfRangeException());
if (Package.SubKeyCount > SUBKEY_MAX)
throw new CryptoProcessingException("PackageFactory:Create", String.Format("The key package can not contain more than {0} keys!", SUBKEY_MAX), new ArgumentOutOfRangeException());
// get the size of a subkey set
int subKeySize = Package.Description.KeySize;
if (Package.Description.IvSize > 0)
subKeySize += Package.Description.IvSize;
if (Package.Description.MacSize > 0)
subKeySize += Package.Description.MacSize;
if (subKeySize < 0)
throw new CryptoProcessingException("PackageFactory:Create", "The key package cipher settings are invalid!", new Exception());
try
{
// store the auth struct and policy
_keyOwner = Package.Authority;
this.KeyPolicy = Package.KeyPolicy;
// get the serialized header
byte[] header = Package.ToBytes();
// size key buffer
byte[] buffer = new byte[subKeySize * Package.SubKeyCount];
// generate the keying material
using (KeyGenerator keyGen = new KeyGenerator(SeedEngine, DigestEngine))
keyGen.GetBytes(buffer);
using (BinaryWriter keyWriter = new BinaryWriter(new FileStream(_keyPath, FileMode.Create, FileAccess.Write)))
{
// pre-set the size to avoid fragmentation
keyWriter.BaseStream.SetLength(PackageKey.GetHeaderSize(Package) + (subKeySize * Package.SubKeyCount));
if (IsEncrypted(Package.KeyPolicy))
{
// add policy flags, only part of key not encrypted
keyWriter.Write(Package.KeyPolicy);
// get salt, return depends on auth flag settings
byte[] salt = GetSalt();
// create a buffer for encrypted data
int hdrLen = header.Length - PackageKey.GetPolicyOffset();
byte[] data = new byte[buffer.Length + hdrLen];
// copy header and key material
Buffer.BlockCopy(header, PackageKey.GetPolicyOffset(), data, 0, hdrLen);
Buffer.BlockCopy(buffer, 0, data, hdrLen, buffer.Length);
// encrypt the key and header
TransformBuffer(data, salt);
// write to file
keyWriter.Write(data);
// don't wait for gc
Array.Clear(salt, 0, salt.Length);
Array.Clear(data, 0, data.Length);
}
else
{
// write the keypackage header
keyWriter.Write(header, 0, header.Length);
// write the keying material
keyWriter.Write(buffer, 0, buffer.Length);
}
}
// cleanup
Array.Clear(header, 0, header.Length);
Array.Clear(buffer, 0, buffer.Length);
}
catch
{
throw;
}
}
/// <summary>
/// Initialize this class with a key file path.
/// <para>If the key exixts, permissions are tested, otherwise this path is used as the new key path and file name.</para>
/// </summary>
///
/// <param name="KeyPath">The fully qualified path to the key file to be read or created</param>
/// <param name="Authority">The local KeyAuthority credentials structure</param>
///
/// <exception cref="CryptoProcessingException">Thrown if an empty KeyPath is used</exception>
public PackageFactory(string KeyPath, KeyAuthority Authority)
{
if (string.IsNullOrEmpty(KeyPath) || Path.GetExtension(KeyPath).Length < 1 || Path.GetFileNameWithoutExtension(KeyPath).Length < 1 || !Path.IsPathRooted(KeyPath))
throw new CryptoProcessingException("PackageFactory:Ctor", "The key path must contain a valid directory and file name!", new ArgumentException());
// store authority
_keyOwner = Authority;
// file path or destination
_keyPath = KeyPath;
if (File.Exists(_keyPath))
AccessScope = Authenticate();
}
/// <summary>
/// Creates a temporary PackageKey on disk, extracts and compares the copy
/// <para>Throws an Exception on failure</</para>
/// </summary>
public static void PackageFactoryTest()
{
string path = GetTempPath();
KeyGenerator kgen = new KeyGenerator();
// populate a KeyAuthority structure
KeyAuthority authority = new KeyAuthority(kgen.GetBytes(16), kgen.GetBytes(16), kgen.GetBytes(16), kgen.GetBytes(32), 0);
// cipher paramaters
CipherDescription desc = new CipherDescription(
SymmetricEngines.RDX, 32,
IVSizes.V128,
CipherModes.CTR,
PaddingModes.X923,
BlockSizes.B128,
RoundCounts.R14,
Digests.Keccak512,
64,
Digests.Keccak512);
// create the package key
PackageKey pkey = new PackageKey(authority, desc, 10);
// write a key file
using (PackageFactory pf = new PackageFactory(path, authority))
pf.Create(pkey);
for (int i = 0; i < pkey.SubKeyCount; i++)
{
CipherDescription desc2;
KeyParams kp1;
KeyParams kp2;
byte[] ext;
byte[] id = pkey.SubKeyID[i];
// get at index
using (FileStream stream = new FileStream(path, FileMode.Open))
kp2 = PackageKey.AtIndex(stream, i);
// read the package from id
using (PackageFactory pf = new PackageFactory(path, authority))
pf.Extract(id, out desc2, out kp1, out ext);
// compare key material
if (!Compare.AreEqual(kp1.Key, kp2.Key))
throw new Exception();
if (!Compare.AreEqual(kp1.IV, kp2.IV))
throw new Exception();
if (!Compare.AreEqual(pkey.ExtensionKey, ext))
throw new Exception();
if (!desc.Equals(desc2))
throw new Exception();
}
if (File.Exists(path))
File.Delete(path);
}
/// <summary>
/// Get this is a valid header file
/// </summary>
///
/// <param name="Authority">The stream containing a KeyAuthority structure</param>
///
/// <returns>Valid</returns>
public static bool IsValid(KeyAuthority Authority)
{
int count = 0;
for (int i = 0; i < Authority.OriginId.Length; i++)
{
if (Authority.OriginId[i] == (byte)0)
count++;
}
return count < 8;
}
