DTLS: Fixed retransmission in response to re-receipt of an aggregated ChangeCipherSpec

- see https://github.com/bcgit/bc-java/pull/1491

2 files changed, 18 insertions, 11 deletions

diff --git a/crypto/src/tls/DtlsRecordLayer.cs b/crypto/src/tls/DtlsRecordLayer.cs

index e3567aa46..fe3b58d41 100644
--- a/crypto/src/tls/DtlsRecordLayer.cs
+++ b/crypto/src/tls/DtlsRecordLayer.cs
@@ -715,10 +715,12 @@ namespace Org.BouncyCastle.Tls
             {
                 recordEpoch = m_readEpoch;
             }
-            else if (recordType == ContentType.handshake && null != m_retransmitEpoch
-                && epoch == m_retransmitEpoch.Epoch)
+            else if (null != m_retransmitEpoch && epoch == m_retransmitEpoch.Epoch)
             {
-                recordEpoch = m_retransmitEpoch;
+                if (recordType == ContentType.handshake)
+                {
+                    recordEpoch = m_retransmitEpoch;
+                }
             }
 
             if (null == recordEpoch)
@@ -994,7 +996,6 @@ namespace Org.BouncyCastle.Tls
             int recordLength = RecordHeaderLength;
             if (m_recordQueue.Available >= recordLength)
             {
-                short recordType = m_recordQueue.ReadUint8(0);
                 int epoch = m_recordQueue.ReadUint16(3);
 
                 DtlsEpoch recordEpoch = null;
@@ -1002,8 +1003,7 @@ namespace Org.BouncyCastle.Tls
                 {
                     recordEpoch = m_readEpoch;
                 }
-                else if (recordType == ContentType.handshake && null != m_retransmitEpoch
-                    && epoch == m_retransmitEpoch.Epoch)
+                else if (null != m_retransmitEpoch && epoch == m_retransmitEpoch.Epoch)
                 {
                     recordEpoch = m_retransmitEpoch;
                 }
@@ -1038,7 +1038,6 @@ namespace Org.BouncyCastle.Tls
             {
                 this.m_inConnection = true;
 
-                short recordType = TlsUtilities.ReadUint8(buf, off);
                 int epoch = TlsUtilities.ReadUint16(buf, off + 3);
 
                 DtlsEpoch recordEpoch = null;
@@ -1046,8 +1045,7 @@ namespace Org.BouncyCastle.Tls
                 {
                     recordEpoch = m_readEpoch;
                 }
-                else if (recordType == ContentType.handshake && null != m_retransmitEpoch
-                    && epoch == m_retransmitEpoch.Epoch)
+                else if (null != m_retransmitEpoch && epoch == m_retransmitEpoch.Epoch)
                 {
                     recordEpoch = m_retransmitEpoch;
                 }
diff --git a/crypto/src/tls/TlsUtilities.cs b/crypto/src/tls/TlsUtilities.cs

index 2887b0df1..67a49e5ef 100644
--- a/crypto/src/tls/TlsUtilities.cs
+++ b/crypto/src/tls/TlsUtilities.cs
@@ -770,11 +770,20 @@ namespace Org.BouncyCastle.Tls
 
         public static int ReadUint16(byte[] buf, int offset)
         {
-            int n = (buf[offset] & 0xff) << 8;
-            n |= (buf[++offset] & 0xff);
+            int n = buf[offset] << 8;
+            n |= buf[++offset];
             return n;
         }
 
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+        public static int ReadUint16(ReadOnlySpan<byte> buffer)
+        {
+            int n = buffer[0] << 8;
+            n |= buffer[1];
+            return n;
+        }
+#endif
+
         public static int ReadUint24(Stream input)
         {
             int i1 = input.ReadByte();