Add Memory/Span accessors to avoid some copies

4 files changed, 49 insertions, 1 deletions

diff --git a/crypto/src/asn1/Asn1OctetString.cs b/crypto/src/asn1/Asn1OctetString.cs
index 8f7da8800..e52e50759 100644
--- a/crypto/src/asn1/Asn1OctetString.cs
+++ b/crypto/src/asn1/Asn1OctetString.cs
@@ -103,7 +103,19 @@ namespace Org.BouncyCastle.Asn1
             return contents;
         }
 
-		protected override int Asn1GetHashCode()
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+        internal ReadOnlyMemory<byte> GetOctetsMemory()
+        {
+            return contents.AsMemory();
+        }
+
+        internal ReadOnlySpan<byte> GetOctetsSpan()
+        {
+            return contents.AsSpan();
+        }
+#endif
+
+        protected override int Asn1GetHashCode()
 		{
 			return Arrays.GetHashCode(GetOctets());
         }
diff --git a/crypto/src/asn1/DerBitString.cs b/crypto/src/asn1/DerBitString.cs
index 2712c3056..b929de357 100644
--- a/crypto/src/asn1/DerBitString.cs
+++ b/crypto/src/asn1/DerBitString.cs
@@ -195,6 +195,24 @@ namespace Org.BouncyCastle.Asn1
             return Arrays.CopyOfRange(contents, 1, contents.Length);
         }
 
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+        internal ReadOnlyMemory<byte> GetOctetsMemory()
+        {
+            if (contents[0] != 0)
+                throw new InvalidOperationException("attempt to get non-octet aligned data from BIT STRING");
+
+            return contents.AsMemory(1);
+        }
+
+        internal ReadOnlySpan<byte> GetOctetsSpan()
+        {
+            if (contents[0] != 0)
+                throw new InvalidOperationException("attempt to get non-octet aligned data from BIT STRING");
+
+            return contents.AsSpan(1);
+        }
+#endif
+
         public virtual byte[] GetBytes()
 		{
             if (contents.Length == 1)
diff --git a/crypto/src/security/PrivateKeyFactory.cs b/crypto/src/security/PrivateKeyFactory.cs
index 5d70423f4..38e571cd6 100644
--- a/crypto/src/security/PrivateKeyFactory.cs
+++ b/crypto/src/security/PrivateKeyFactory.cs
@@ -350,10 +350,17 @@ namespace Org.BouncyCastle.Security
             }
         }
 
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+        private static ReadOnlySpan<byte> GetRawKey(PrivateKeyInfo keyInfo)
+        {
+            return Asn1OctetString.GetInstance(keyInfo.ParsePrivateKey()).GetOctetsSpan();
+        }
+#else
         private static byte[] GetRawKey(PrivateKeyInfo keyInfo)
         {
             return Asn1OctetString.GetInstance(keyInfo.ParsePrivateKey()).GetOctets();
         }
+#endif
 
         public static AsymmetricKeyParameter DecryptKey(
             char[] passPhrase,
diff --git a/crypto/src/security/PublicKeyFactory.cs b/crypto/src/security/PublicKeyFactory.cs
index 775884e94..03cabbb13 100644
--- a/crypto/src/security/PublicKeyFactory.cs
+++ b/crypto/src/security/PublicKeyFactory.cs
@@ -280,6 +280,16 @@ namespace Org.BouncyCastle.Security
             }
         }
 
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+        private static ReadOnlySpan<byte> GetRawKey(SubjectPublicKeyInfo keyInfo)
+        {
+            /*
+             * TODO[RFC 8422]
+             * - Require keyInfo.Algorithm.Parameters == null?
+             */
+            return keyInfo.PublicKeyData.GetOctetsSpan();
+        }
+#else
         private static byte[] GetRawKey(SubjectPublicKeyInfo keyInfo)
         {
             /*
@@ -288,6 +298,7 @@ namespace Org.BouncyCastle.Security
              */
             return keyInfo.PublicKeyData.GetOctets();
         }
+#endif
 
         private static bool IsPkcsDHParam(Asn1Sequence seq)
         {