Invalid mac

[brookman]

Hi. Thanks for providing this awesome crate!🦀

I am trying to connect to a device which runs WebRTC (afaik implemented in Python). I can successfully connect but get an error when trying to open a data channel.

Opening a data channel between Flutter and the device works fine.

Logs:

2024-02-19T15:47:19.023741Z  INFO webrtc_ice::agent::agent_internal: [controlling]: Setting new connection state: Connected
2024-02-19T15:47:19.023908Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 0: Preparing
2024-02-19T15:47:19.023989Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 0: Sending
2024-02-19T15:47:19.023959Z  INFO webrtc::peer_connection: ICE connection state changed: connected
2024-02-19T15:47:19.024098Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 0: Waiting
2024-02-19T15:47:19.024151Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 35
2024-02-19T15:47:19.024611Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 22
2024-02-19T15:47:19.024903Z TRACE webrtc_dtls::conn: Recv [handshake:server] -> ClientHello (epoch: 0, seq: 0)
2024-02-19T15:47:19.025137Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 35
2024-02-19T15:47:19.025218Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 22
2024-02-19T15:47:19.025290Z DEBUG webrtc_dtls::flight::flight0: [handshake:server] use cipher suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
2024-02-19T15:47:19.025485Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 0 -> Flight 2
2024-02-19T15:47:19.025557Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 2: Preparing
2024-02-19T15:47:19.025627Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 2: Sending
2024-02-19T15:47:19.025701Z TRACE webrtc_dtls::conn: Send [handshake:server] -> HelloVerifyRequest (epoch: 0, seq: 0)
2024-02-19T15:47:19.025829Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 2: Waiting
2024-02-19T15:47:19.027601Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 35
2024-02-19T15:47:19.027759Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 22
2024-02-19T15:47:19.027860Z TRACE webrtc_dtls::conn: Recv [handshake:server] -> ClientHello (epoch: 0, seq: 1)
2024-02-19T15:47:19.028012Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 35
2024-02-19T15:47:19.028105Z  WARN webrtc_dtls::handshake::handshake_message_client_hello: Unsupported Extension Type 0 22
2024-02-19T15:47:19.028186Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 2 -> Flight 4
2024-02-19T15:47:19.028338Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 4: Preparing
2024-02-19T15:47:19.028525Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 4: Sending
2024-02-19T15:47:19.028614Z TRACE webrtc_dtls::conn: Send [handshake:server] -> ServerHello (epoch: 0, seq: 1)
2024-02-19T15:47:19.028798Z TRACE webrtc_dtls::conn: Send [handshake:server] -> Certificate (epoch: 0, seq: 2)
2024-02-19T15:47:19.028880Z TRACE webrtc_dtls::conn: Send [handshake:server] -> ServerKeyExchange (epoch: 0, seq: 3)
2024-02-19T15:47:19.028954Z TRACE webrtc_dtls::conn: Send [handshake:server] -> CertificateRequest (epoch: 0, seq: 4)
2024-02-19T15:47:19.029034Z TRACE webrtc_dtls::conn: Send [handshake:server] -> ServerHelloDone (epoch: 0, seq: 5)
2024-02-19T15:47:19.029174Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 4: Waiting
2024-02-19T15:47:19.036359Z TRACE webrtc_dtls::conn: Recv [handshake:server] -> Certificate (epoch: 0, seq: 2)    
2024-02-19T15:47:19.036485Z TRACE webrtc_dtls::conn: Recv [handshake:server] -> ClientKeyExchange (epoch: 0, seq: 3)
2024-02-19T15:47:19.036592Z TRACE webrtc_dtls::conn: Recv [handshake:server] -> CertificateVerify (epoch: 0, seq: 4)
2024-02-19T15:47:19.036660Z DEBUG webrtc_dtls::conn: server: CipherSuite not initialized, queuing packet
2024-02-19T15:47:19.036774Z DEBUG webrtc_dtls::conn: server: received packet of next epoch, queuing packet
2024-02-19T15:47:19.036861Z TRACE webrtc_dtls::flight::flight4: [handshake] PeerCertificates4 1
2024-02-19T15:47:19.036947Z TRACE webrtc_dtls::crypto: Picked an algorithm ECDSA_P256_SHA256_ASN1
2024-02-19T15:47:19.037241Z TRACE webrtc_dtls::conn: server: <- ChangeCipherSpec (epoch: 1)
2024-02-19T15:47:19.037335Z DEBUG webrtc_dtls::conn: server: decrypt failed: invalid mac
...
2024-02-19T12:43:32.145109Z TRACE webrtc_dtls::flight::flight4: [handshake] PeerCertificates4 1    
2024-02-19T12:43:32.145792Z TRACE webrtc_dtls::crypto: Picked an algorithm ECDSA_P256_SHA256_ASN1
2024-02-19T12:43:32.146344Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 4 result alert:None, err:None
2024-02-19T12:43:32.146772Z TRACE webrtc_dtls::flight::flight4: [handshake] PeerCertificates4 1
2024-02-19T12:43:32.147006Z TRACE webrtc_dtls::crypto: Picked an algorithm ECDSA_P256_SHA256_ASN1
2024-02-19T12:43:32.147258Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 4 result alert:None, err:None
2024-02-19T12:43:32.147443Z TRACE webrtc_dtls::flight::flight4: [handshake] PeerCertificates4 1
2024-02-19T12:43:32.147612Z TRACE webrtc_dtls::crypto: Picked an algorithm ECDSA_P256_SHA256_ASN1
2024-02-19T12:43:32.147751Z TRACE webrtc_dtls::handshaker: [handshake:server] Flight 4 result alert:None, err:None
2024-02-19T12:43:32.147892Z TRACE webrtc_dtls::conn: server: <- ChangeCipherSpec (epoch: 1)
2024-02-19T12:43:32.147980Z DEBUG webrtc_dtls::conn: server: decrypt failed: invalid mac

I have tried to force it to use different algorithms than TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA but without success.

Btw. I'm on Windows and use no features like "openssl" or "vendored-openssl".

[brookman]

Meanwhile I have tried it again by upgrading to the newest crate version and using the "openssl" feature:
webrtc = { "version" = "0.10.1", "features" = ["openssl"] }

I installed OpenSSL on Windows like this:

cd c:
git clone https://github.com/microsoft/vcpkg.git
cd vcpkg
bootstrap-vcpkg.bat
vcpkg integrate install
vcpkg install openssl
[create env var OPENSSL_DIR=c:\vcpkg\packages\openssl_x64-windows]

I can compile it but unfortunately I'm still getting the same error when trying to open a data channel.

[edaniels]

@brookman this is fixed by 4e09f92. I'm not sure why the code was changed at 0.9.0 and I'm trying to understand @ #557 (comment)

[brookman]

@edaniels Thanks for the update. Using the newly released version 0.11.0 I can now successfully establish data channels.