Added support for SHA384 and SHA512 hashing algorithms with RSASSA-PK…

…CS1-v1_5 (#305)

* Added RSAAlgorithm abstract base class which all RSA algorithms derive from
* Added RS384Algorithm, RS512Algorithm
* Refactored RSAlgorithmFactory 
* Updated, added tests
* Bumped version to 8.0.0

src/JWT/Algorithms/HMACSHA256Algorithm.cs

@@ -16,5 +16,12 @@ public byte[] Sign(byte[] key, byte[] bytesToSign)
 
         /// <inheritdoc />
         public string Name => JwtAlgorithmName.HS256.ToString();
+
+        public string HashAlgorithm =>
+#if NET35 || NET40
+            HashAlgorithmName.SHA256;
+#else
+            HashAlgorithmName.SHA256.Name;
+#endif
     }
 }

src/JWT/Algorithms/HMACSHA384Algorithm.cs

@@ -16,5 +16,12 @@ public byte[] Sign(byte[] key, byte[] bytesToSign)
 
         /// <inheritdoc />
         public string Name => JwtAlgorithmName.HS384.ToString();
+
+        public string HashAlgorithm =>
+#if NET35 || NET40
+            HashAlgorithmName.SHA384;
+#else
+            HashAlgorithmName.SHA384.Name;
+#endif
     }
 }

src/JWT/Algorithms/HMACSHA512Algorithm.cs

@@ -16,5 +16,12 @@ public byte[] Sign(byte[] key, byte[] bytesToSign)
 
         /// <inheritdoc />
         public string Name => JwtAlgorithmName.HS512.ToString();
+
+        public string HashAlgorithm =>
+#if NET35 || NET40
+            HashAlgorithmName.SHA512;
+#else
+            HashAlgorithmName.SHA512.Name;
+#endif
     }
 }

src/JWT/Algorithms/IJwtAlgorithm.cs

@@ -16,6 +16,11 @@ public interface IJwtAlgorithm
         /// Gets algorithm name.
         /// </summary>
         string Name { get; }
+
+        /// <summary>
+        /// Gets name of the hashing algorithm (e.g. SHA-256/SHA-384/SHA-512).
+        /// </summary>
+        string HashAlgorithm { get; }
     }
 
     /// <summary>

src/JWT/Algorithms/JwtAlgorithmName.cs

@@ -23,6 +23,16 @@ public enum JwtAlgorithmName
         /// <summary>
         /// RSASSA-PKCS1-v1_5 using SHA-256
         /// </summary>
-        RS256
+        RS256,
+
+        /// <summary>
+        /// RSASSA-PKCS1-v1_5 using SHA-384
+        /// </summary>
+        RS384,
+
+        /// <summary>
+        /// RSASSA-PKCS1-v1_5 using SHA-512
+        /// </summary>
+        RS512
     }
 }

src/JWT/Algorithms/RS256Algorithm.cs

@@ -1,26 +1,21 @@
-using System;
-using System.Security.Cryptography;
+using System.Security.Cryptography;
 using System.Security.Cryptography.X509Certificates;
 
 namespace JWT.Algorithms
 {
     /// <summary>
     /// RSASSA-PKCS1-v1_5 using SHA-256
     /// </summary>
-    public sealed class RS256Algorithm : IAsymmetricAlgorithm
+    public sealed class RS256Algorithm : RSAlgorithm
     {
-        private readonly RSA _publicKey;
-        private readonly RSA _privateKey;
-
         /// <summary>
         /// Creates an instance of <see cref="RS256Algorithm" /> using the provided pair of public and private keys.
         /// </summary>
         /// <param name="publicKey">The public key for verifying the data.</param>
         /// <param name="privateKey">The private key for signing the data.</param>
         public RS256Algorithm(RSA publicKey, RSA privateKey)
+            : base(publicKey, privateKey)
         {
-            _publicKey = publicKey ?? throw new ArgumentNullException(nameof(publicKey));
-            _privateKey = privateKey ?? throw new ArgumentNullException(nameof(privateKey));
         }
 
         /// <summary>
@@ -31,75 +26,26 @@ public RS256Algorithm(RSA publicKey, RSA privateKey)
         /// </remarks>
         /// <param name="publicKey">The public key for verifying the data.</param>
         public RS256Algorithm(RSA publicKey)
+            : base(publicKey)
         {
-            _publicKey = publicKey ?? throw new ArgumentNullException(nameof(publicKey));
-            _privateKey = null;
         }
 
         /// <summary>
         /// Creates an instance using the provided certificate.
         /// </summary>
         /// <param name="cert">The certificate having a public key and an optional private key.</param>
         public RS256Algorithm(X509Certificate2 cert)
+            : base(cert)
         {
-            _publicKey = GetPublicKey(cert) ?? throw new Exception("Certificate's PublicKey cannot be null.");
-            _privateKey = GetPrivateKey(cert);
         }
 
         /// <inheritdoc />
-        public string Name => JwtAlgorithmName.RS256.ToString();
-
-        /// <inheritdoc />
-        public byte[] Sign(byte[] key, byte[] bytesToSign)
-        {
-            if (_privateKey is null)
-                throw new InvalidOperationException("Can't sign data without private key");
+        public override string Name => JwtAlgorithmName.RS256.ToString();
 
-            return Sign(bytesToSign);
-        }
-
-        /// <summary>
-        /// Signs the provided bytes.
-        /// </summary>
-        /// <param name="bytesToSign">The bytes to sign.</param>
-        /// <returns>The signed bytes.</returns>
-        public byte[] Sign(byte[] bytesToSign) =>
-#if NET35 || NET40
-            ((RSACryptoServiceProvider)_privateKey).SignData(bytesToSign, HashAlgorithmName.SHA256);
-#else
-            _privateKey.SignData(bytesToSign, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
-#endif
-
-        /// <inheritdoc />
-        public bool Verify(byte[] bytesToSign, byte[] signature) =>
 #if NET35 || NET40
-            ((RSACryptoServiceProvider)_publicKey).VerifyData(bytesToSign, HashAlgorithmName.SHA256, signature);
+        protected override string HashAlgorithmInternal => HashAlgorithmName.SHA256;
 #else
-            _publicKey.VerifyData(bytesToSign, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
+        protected override HashAlgorithmName HashAlgorithmInternal => HashAlgorithmName.SHA256;
 #endif
-
-        private static RSA GetPrivateKey(X509Certificate2 cert)
-        {
-            if (cert is null)
-                throw new ArgumentNullException(nameof(cert));
-
-#if NETSTANDARD1_3
-            return cert.GetRSAPrivateKey();
-#else
-            return (RSA)cert.PrivateKey;
-#endif
-        }
-
-        private static RSA GetPublicKey(X509Certificate2 cert)
-        {
-            if (cert is null)
-                throw new ArgumentNullException(nameof(cert));
-
-#if NETSTANDARD1_3
-            return cert.GetRSAPublicKey();
-#else
-            return (RSA)cert.PublicKey.Key;
-#endif
-        }
     }
 }

src/JWT/Algorithms/RS384Algorithm.cs

@@ -0,0 +1,51 @@
+using System.Security.Cryptography;
+using System.Security.Cryptography.X509Certificates;
+
+namespace JWT.Algorithms
+{
+    /// <summary>
+    /// RSASSA-PKCS1-v1_5 using SHA-384
+    /// </summary>
+    public sealed class RS384Algorithm : RSAlgorithm
+    {
+        /// <summary>
+        /// Creates an instance of <see cref="RS384Algorithm" /> using the provided pair of public and private keys.
+        /// </summary>
+        /// <param name="publicKey">The public key for verifying the data.</param>
+        /// <param name="privateKey">The private key for signing the data.</param>
+        public RS384Algorithm(RSA publicKey, RSA privateKey)
+            : base(publicKey, privateKey)
+        {
+        }
+
+        /// <summary>
+        /// Creates an instance of <see cref="RS384Algorithm" /> using the provided public key only.
+        /// </summary>
+        /// <remarks>
+        /// An instance created using this constructor can only be used for verifying the data, not for signing it.
+        /// </remarks>
+        /// <param name="publicKey">The public key for verifying the data.</param>
+        public RS384Algorithm(RSA publicKey)
+            : base(publicKey)
+        {
+        }
+
+        /// <summary>
+        /// Creates an instance using the provided certificate.
+        /// </summary>
+        /// <param name="cert">The certificate having a public key and an optional private key.</param>
+        public RS384Algorithm(X509Certificate2 cert)
+            : base(cert)
+        {
+        }
+
+        /// <inheritdoc />
+        public override string Name => JwtAlgorithmName.RS384.ToString();
+
+#if NET35 || NET40
+        protected override string HashAlgorithmInternal => HashAlgorithmName.SHA384;
+#else
+        protected override HashAlgorithmName HashAlgorithmInternal => HashAlgorithmName.SHA384;
+#endif
+    }
+}

src/JWT/Algorithms/RS512Algorithm.cs

@@ -0,0 +1,51 @@
+using System.Security.Cryptography;
+using System.Security.Cryptography.X509Certificates;
+
+namespace JWT.Algorithms
+{
+    /// <summary>
+    /// RSASSA-PKCS1-v1_5 using SHA-512
+    /// </summary>
+    public sealed class RS512Algorithm : RSAlgorithm
+    {
+        /// <summary>
+        /// Creates an instance of <see cref="RS512Algorithm" /> using the provided pair of public and private keys.
+        /// </summary>
+        /// <param name="publicKey">The public key for verifying the data.</param>
+        /// <param name="privateKey">The private key for signing the data.</param>
+        public RS512Algorithm(RSA publicKey, RSA privateKey)
+            : base(publicKey, privateKey)
+        {
+        }
+
+        /// <summary>
+        /// Creates an instance of <see cref="RS512Algorithm" /> using the provided public key only.
+        /// </summary>
+        /// <remarks>
+        /// An instance created using this constructor can only be used for verifying the data, not for signing it.
+        /// </remarks>
+        /// <param name="publicKey">The public key for verifying the data.</param>
+        public RS512Algorithm(RSA publicKey)
+            : base(publicKey)
+        {
+        }
+
+        /// <summary>
+        /// Creates an instance using the provided certificate.
+        /// </summary>
+        /// <param name="cert">The certificate having a public key and an optional private key.</param>
+        public RS512Algorithm(X509Certificate2 cert)
+            : base(cert)
+        {
+        }
+
+        /// <inheritdoc />
+        public override string Name => JwtAlgorithmName.RS512.ToString();
+
+#if NET35 || NET40
+        protected override string HashAlgorithmInternal => HashAlgorithmName.SHA512;
+#else
+        protected override HashAlgorithmName HashAlgorithmInternal => HashAlgorithmName.SHA512;
+#endif
+    }
+}