/// <summary>
/// DescriptorExists
/// </summary>
/// <param name="sercure_name"></param>
/// <param name="store"></param>
/// <param name="crypto"></param>
/// <returns></returns>
public static bool DescriptorExists(string sercure_name, IStorage store, CryptographyLib.ICryptography crypto)
{
string sub_dir_name = StoragePath.GetDirectory(sercure_name);
string secure_sub_dir_name = SecureStorageUtility.GetSecureName(sub_dir_name, crypto.Key);
return(store.Exists(secure_sub_dir_name));
}
/// <summary>
/// CreateFile
/// </summary>
/// <param name="name">name of file</param>
/// <param name="data">file data</param>
public void CreateFile(string name, byte[] data)
{
// get all names
string secure_name = GetSecureName(name);
string dir_name = StoragePath.GetDirectory(name);
string secure_dir_name = GetSecureName(dir_name);
// encrypt file to upload
byte[] encrypted_data = crypto.Encrypt(data);
// upload file
CreateAppendFragment(secure_name, encrypted_data);
// create/append xml file node to xml directory node
XmlDocument doc = GetDirectoryDocument(secure_dir_name);
string hash = null;
byte[] sha256 = SecureStorageUtility.SHA256(data);
hash = Convert.ToBase64String(sha256);
AppendFileXml(doc, name, hash);
// delete old directory file
Store.Delete(secure_dir_name);
// create new directory file
string xml = doc.OuterXml;
data = Encoding.UTF8.GetBytes(xml);
encrypted_data = crypto.Encrypt(data);
Store.Create(secure_dir_name, encrypted_data, FileMode.Append);
}
/// <summary>
/// get a secure name
/// </summary>
/// <param name="name">orginal name</param>
/// <returns>secure name based off original</returns>
private string GetSecureName(string name)
{
byte[] hash = SecureStorageUtility.HMACSHA256(name, crypto.Key);
return(SecureStorageUtility.FromBytesToHex(hash));
}
/// <summary>
/// ReadFileSignatureXml
/// </summary>
/// <param name="doc"></param>
/// <param name="name"></param>
/// <returns></returns>
private string ReadFileSignatureXml(XmlDocument doc, string name)
{
return(SecureStorageUtility.ReadFileSignatureXml(doc, name));
}
/// <summary>
/// GetSecureHash
/// </summary>
/// <param name="data">data</param>
/// <returns>string</returns>
public string GetSecureHash(string data)
{
byte[] hash = SecureStorageUtility.HMACSHA256(data, Key);
return(SecureStorageUtility.FromBytesToHex(hash));
}
