Improve EdDSA/XDH key validation

10 files changed, 118 insertions, 22 deletions

diff --git a/crypto/src/crypto/parameters/Ed25519PrivateKeyParameters.cs b/crypto/src/crypto/parameters/Ed25519PrivateKeyParameters.cs
index 531bca0e9..4e61a0f8d 100644
--- a/crypto/src/crypto/parameters/Ed25519PrivateKeyParameters.cs
+++ b/crypto/src/crypto/parameters/Ed25519PrivateKeyParameters.cs
@@ -24,6 +24,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
             Ed25519.GeneratePrivateKey(random, data);
         }
 
+        public Ed25519PrivateKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public Ed25519PrivateKeyParameters(byte[] buf, int off)
             : base(true)
         {
@@ -106,5 +111,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
             }
             }
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/Ed25519PublicKeyParameters.cs b/crypto/src/crypto/parameters/Ed25519PublicKeyParameters.cs
index 96e9ec21f..8a9139e8d 100644
--- a/crypto/src/crypto/parameters/Ed25519PublicKeyParameters.cs
+++ b/crypto/src/crypto/parameters/Ed25519PublicKeyParameters.cs
@@ -14,6 +14,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
 
         private readonly byte[] data = new byte[KeySize];
 
+        public Ed25519PublicKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public Ed25519PublicKeyParameters(byte[] buf, int off)
             : base(false)
         {
@@ -36,5 +41,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
         {
             return Arrays.Clone(data);
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/Ed448PrivateKeyParameters.cs b/crypto/src/crypto/parameters/Ed448PrivateKeyParameters.cs
index 1b38143fa..705ad8c53 100644
--- a/crypto/src/crypto/parameters/Ed448PrivateKeyParameters.cs
+++ b/crypto/src/crypto/parameters/Ed448PrivateKeyParameters.cs
@@ -24,6 +24,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
             Ed448.GeneratePrivateKey(random, data);
         }
 
+        public Ed448PrivateKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public Ed448PrivateKeyParameters(byte[] buf, int off)
             : base(true)
         {
@@ -98,5 +103,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
             }
             }
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/Ed448PublicKeyParameters.cs b/crypto/src/crypto/parameters/Ed448PublicKeyParameters.cs
index d7faac246..8a89be08f 100644
--- a/crypto/src/crypto/parameters/Ed448PublicKeyParameters.cs
+++ b/crypto/src/crypto/parameters/Ed448PublicKeyParameters.cs
@@ -14,6 +14,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
 
         private readonly byte[] data = new byte[KeySize];
 
+        public Ed448PublicKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public Ed448PublicKeyParameters(byte[] buf, int off)
             : base(false)
         {
@@ -36,5 +41,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
         {
             return Arrays.Clone(data);
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/X25519PrivateKeyParameters.cs b/crypto/src/crypto/parameters/X25519PrivateKeyParameters.cs
index c9aaad949..63e72d3a7 100644
--- a/crypto/src/crypto/parameters/X25519PrivateKeyParameters.cs
+++ b/crypto/src/crypto/parameters/X25519PrivateKeyParameters.cs
@@ -22,6 +22,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
             X25519.GeneratePrivateKey(random, data);
         }
 
+        public X25519PrivateKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public X25519PrivateKeyParameters(byte[] buf, int off)
             : base(true)
         {
@@ -59,5 +64,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
             if (!X25519.CalculateAgreement(data, 0, encoded, 0, buf, off))
                 throw new InvalidOperationException("X25519 agreement failed");
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/X25519PublicKeyParameters.cs b/crypto/src/crypto/parameters/X25519PublicKeyParameters.cs
index 7df5f624d..c28e4de16 100644
--- a/crypto/src/crypto/parameters/X25519PublicKeyParameters.cs
+++ b/crypto/src/crypto/parameters/X25519PublicKeyParameters.cs
@@ -14,6 +14,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
 
         private readonly byte[] data = new byte[KeySize];
 
+        public X25519PublicKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public X25519PublicKeyParameters(byte[] buf, int off)
             : base(false)
         {
@@ -36,5 +41,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
         {
             return Arrays.Clone(data);
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/X448PrivateKeyParameters.cs b/crypto/src/crypto/parameters/X448PrivateKeyParameters.cs
index 35eb1c4f7..d10a9035f 100644
--- a/crypto/src/crypto/parameters/X448PrivateKeyParameters.cs
+++ b/crypto/src/crypto/parameters/X448PrivateKeyParameters.cs
@@ -22,6 +22,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
             X448.GeneratePrivateKey(random, data);
         }
 
+        public X448PrivateKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public X448PrivateKeyParameters(byte[] buf, int off)
             : base(true)
         {
@@ -59,5 +64,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
             if (!X448.CalculateAgreement(data, 0, encoded, 0, buf, off))
                 throw new InvalidOperationException("X448 agreement failed");
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/crypto/parameters/X448PublicKeyParameters.cs b/crypto/src/crypto/parameters/X448PublicKeyParameters.cs
index 6c566ddf2..704d2f7c1 100644
--- a/crypto/src/crypto/parameters/X448PublicKeyParameters.cs
+++ b/crypto/src/crypto/parameters/X448PublicKeyParameters.cs
@@ -14,6 +14,11 @@ namespace Org.BouncyCastle.Crypto.Parameters
 
         private readonly byte[] data = new byte[KeySize];
 
+        public X448PublicKeyParameters(byte[] buf)
+            : this(Validate(buf), 0)
+        {
+        }
+
         public X448PublicKeyParameters(byte[] buf, int off)
             : base(false)
         {
@@ -36,5 +41,13 @@ namespace Org.BouncyCastle.Crypto.Parameters
         {
             return Arrays.Clone(data);
         }
+
+        private static byte[] Validate(byte[] buf)
+        {
+            if (buf.Length != KeySize)
+                throw new ArgumentException("must have length " + KeySize, "buf");
+
+            return buf;
+        }
     }
 }
diff --git a/crypto/src/security/PrivateKeyFactory.cs b/crypto/src/security/PrivateKeyFactory.cs
index dfc73c2cd..408c8b6a0 100644
--- a/crypto/src/security/PrivateKeyFactory.cs
+++ b/crypto/src/security/PrivateKeyFactory.cs
@@ -174,26 +174,26 @@ namespace Org.BouncyCastle.Security
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_X25519))
             {
-                return new X25519PrivateKeyParameters(GetRawKey(keyInfo, X25519PrivateKeyParameters.KeySize), 0);
+                return new X25519PrivateKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_X448))
             {
-                return new X448PrivateKeyParameters(GetRawKey(keyInfo, X448PrivateKeyParameters.KeySize), 0);
+                return new X448PrivateKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_Ed25519))
             {
-                return new Ed25519PrivateKeyParameters(GetRawKey(keyInfo, Ed25519PrivateKeyParameters.KeySize), 0);
+                return new Ed25519PrivateKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_Ed448))
             {
-                return new Ed448PrivateKeyParameters(GetRawKey(keyInfo, Ed448PrivateKeyParameters.KeySize), 0);
+                return new Ed448PrivateKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_512)
                      || algOid.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_256))
             {
                 Gost3410PublicKeyAlgParameters gostParams = Gost3410PublicKeyAlgParameters.GetInstance(keyInfo.PrivateKeyAlgorithm.Parameters);
-                ECGost3410Parameters ecSpec = null;
-                BigInteger d = null;
+                ECGost3410Parameters ecSpec;
+                BigInteger d;
                 Asn1Object p = keyInfo.PrivateKeyAlgorithm.Parameters.ToAsn1Object();
                 if (p is Asn1Sequence && (Asn1Sequence.GetInstance(p).Count == 2 || Asn1Sequence.GetInstance(p).Count == 3))
                 {
@@ -280,13 +280,9 @@ namespace Org.BouncyCastle.Security
             }
         }
 
-        private static byte[] GetRawKey(PrivateKeyInfo keyInfo, int expectedSize)
+        private static byte[] GetRawKey(PrivateKeyInfo keyInfo)
         {
-            byte[] result = Asn1OctetString.GetInstance(keyInfo.ParsePrivateKey()).GetOctets();
-            if (expectedSize != result.Length)
-                throw new SecurityUtilityException("private key encoding has incorrect length");
-
-            return result;
+            return Asn1OctetString.GetInstance(keyInfo.ParsePrivateKey()).GetOctets();
         }
 
         public static AsymmetricKeyParameter DecryptKey(
diff --git a/crypto/src/security/PublicKeyFactory.cs b/crypto/src/security/PublicKeyFactory.cs
index 15af90f91..10b2aacdc 100644
--- a/crypto/src/security/PublicKeyFactory.cs
+++ b/crypto/src/security/PublicKeyFactory.cs
@@ -217,19 +217,19 @@ namespace Org.BouncyCastle.Security
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_X25519))
             {
-                return new X25519PublicKeyParameters(GetRawKey(keyInfo, X25519PublicKeyParameters.KeySize), 0);
+                return new X25519PublicKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_X448))
             {
-                return new X448PublicKeyParameters(GetRawKey(keyInfo, X448PublicKeyParameters.KeySize), 0);
+                return new X448PublicKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_Ed25519))
             {
-                return new Ed25519PublicKeyParameters(GetRawKey(keyInfo, Ed25519PublicKeyParameters.KeySize), 0);
+                return new Ed25519PublicKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(EdECObjectIdentifiers.id_Ed448))
             {
-                return new Ed448PublicKeyParameters(GetRawKey(keyInfo, Ed448PublicKeyParameters.KeySize), 0);
+                return new Ed448PublicKeyParameters(GetRawKey(keyInfo));
             }
             else if (algOid.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_256)
                 ||   algOid.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_512))
@@ -282,17 +282,13 @@ namespace Org.BouncyCastle.Security
             }
         }
 
-        private static byte[] GetRawKey(SubjectPublicKeyInfo keyInfo, int expectedSize)
+        private static byte[] GetRawKey(SubjectPublicKeyInfo keyInfo)
         {
             /*
              * TODO[RFC 8422]
              * - Require keyInfo.Algorithm.Parameters == null?
              */
-            byte[] result = keyInfo.PublicKeyData.GetOctets();
-            if (expectedSize != result.Length)
-                throw new SecurityUtilityException("public key encoding has incorrect length");
-
-            return result;
+            return keyInfo.PublicKeyData.GetOctets();
         }
 
         private static bool IsPkcsDHParam(Asn1Sequence seq)