Implementation of SecureString and CryptoRngProvider

2026-07-16 06:29:29 +00:00 · 2021-07-15 16:11:05 +03:00
parent 1711dd2ec2
commit 68ec8f983d
8 changed files with 324 additions and 3 deletions
@@ -0,0 +1,89 @@
+using System.Security.Cryptography;
+using System.Text;
+
+namespace System.Encryption
+{
+    public sealed class SecureString
+    {
+        private static byte[] optionalEntropy;
+        private byte[] encryptedValue;
+
+        public string Value {
+            get => this.encryptedValue is not null ? Encoding.UTF8.GetString(ProtectedData.Unprotect(this.encryptedValue, optionalEntropy, DataProtectionScope.CurrentUser)) : null;
+            private set => this.encryptedValue = ProtectedData.Protect(Encoding.UTF8.GetBytes(value), optionalEntropy, DataProtectionScope.CurrentUser);
+        }
+
+        public SecureString(string value)
+        {
+            this.Value = value;
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (obj is string)
+            {
+                return this == (obj as string);
+            }
+            else if (obj is SecureString)
+            {
+                return this == (obj as SecureString);
+            }
+            else
+            {
+                return base.Equals(obj);
+            }
+        }
+        public override int GetHashCode()
+        {
+            return this.Value.GetHashCode();
+        }
+        public override string ToString()
+        {
+            return this.Value;
+        }
+
+        public static readonly SecureString Empty = new(string.Empty);
+        public static implicit operator string(SecureString ss) => ss is null ? string.Empty : ss.Value;
+        public static implicit operator SecureString(string s) => new(s);
+        public static SecureString operator +(SecureString ss1, SecureString ss2)
+        {
+            if (ss1 is null) throw new ArgumentNullException(nameof(ss1));
+            if (ss2 is null) throw new ArgumentNullException(nameof(ss2));
+
+            return new SecureString(ss1.Value + ss2.Value);
+        }
+        public static SecureString operator +(SecureString ss1, string s2)
+        {
+            if (ss1 is null) throw new ArgumentNullException(nameof(ss1));
+
+            return new SecureString(ss1.Value + s2);
+        }
+        public static SecureString operator +(SecureString ss1, char c)
+        {
+            if (ss1 is null) throw new ArgumentNullException(nameof(ss1));
+
+            return new SecureString(ss1.Value + c);
+        }
+        public static bool operator ==(SecureString ss1, SecureString ss2)
+        {
+            return ss1?.Value == ss2?.Value;
+        }
+        public static bool operator !=(SecureString ss1, SecureString ss2)
+        {
+            return !(ss1 == ss2);
+        }
+        public static bool operator ==(SecureString ss1, string s2)
+        {
+            return ss1?.Value == s2;
+        }
+        public static bool operator !=(SecureString ss1, string s2)
+        {
+            return !(ss1?.Value == s2);
+        }
+
+        public static void AddOptionalEntropy(byte[] entropy)
+        {
+            optionalEntropy = entropy;
+        }
+    }
+}