mobius-software-ltd / java-dtls Goto Github PK

when and how the dtls client will retransmit the lost handshake message?

Seems to be a problem with key refreshing or something. In GCM-Mode I get "GCM cipher cannot be reused for encryption", in CBC I get "org.bouncycastle.crypto.tls.TlsFatalAlert: bad_record_mac(20)" . I'm using your DtlsClient and DtlsServer .

I'm testing with a modified version of the test code where i keep the DtlsServer open, and repeatedly connect using the DtlsClient, as configured in DtlsTest.testDtls(). However, if I fix the client's port value, the client never receives a response to CLIENT_HELLO during handshake on the second connection.

Debugging the issue, it appears the new server is halting processing of the new CLIENT_HELLO in AsyncDtlsRecordLayer.receive, on line 187.
PendingTransportData nextPacket=pendingTransportMessages.get(readEpoch.getEpoch()).remove(lastProcessedTransportSequence.get());
where
pendingTransportMessages = {0={0=com.mobius.software.iot.dal.crypto.PendingTransportData@157f0bd6}, 1={}} readEpoch.getEpoch() = 1 lastProcessedTransportSequence.get() = 2
DtlsDemo.zip

NoClassDefFoundError: org/bouncycastle/crypto/tls/TlsFatalAlert

In BouncyCastle 1.68 this class seems to be renamed to org.bouncycastle.tls.TlsFatalAlert

If we want to send data which is large than MAX_FRAGMENT_LENGTH, how should we implement?

Should we break down into fragments and construct them back on the server?