status-go/vendor/github.com/pion/dtls/v2/flight5bhandler.go

79 lines
2.3 KiB
Go

// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
// SPDX-License-Identifier: MIT
package dtls
import (
"context"
"github.com/pion/dtls/v2/pkg/crypto/prf"
"github.com/pion/dtls/v2/pkg/protocol"
"github.com/pion/dtls/v2/pkg/protocol/alert"
"github.com/pion/dtls/v2/pkg/protocol/handshake"
"github.com/pion/dtls/v2/pkg/protocol/recordlayer"
)
func flight5bParse(_ context.Context, _ flightConn, state *State, cache *handshakeCache, cfg *handshakeConfig) (flightVal, *alert.Alert, error) {
_, msgs, ok := cache.fullPullMap(state.handshakeRecvSequence-1, state.cipherSuite,
handshakeCachePullRule{handshake.TypeFinished, cfg.initialEpoch + 1, false, false},
)
if !ok {
// No valid message received. Keep reading
return 0, nil, nil
}
if _, ok = msgs[handshake.TypeFinished].(*handshake.MessageFinished); !ok {
return 0, &alert.Alert{Level: alert.Fatal, Description: alert.InternalError}, nil
}
// Other party may re-transmit the last flight. Keep state to be flight5b.
return flight5b, nil, nil
}
func flight5bGenerate(_ flightConn, state *State, cache *handshakeCache, cfg *handshakeConfig) ([]*packet, *alert.Alert, error) { //nolint:gocognit
var pkts []*packet
pkts = append(pkts,
&packet{
record: &recordlayer.RecordLayer{
Header: recordlayer.Header{
Version: protocol.Version1_2,
},
Content: &protocol.ChangeCipherSpec{},
},
})
if len(state.localVerifyData) == 0 {
plainText := cache.pullAndMerge(
handshakeCachePullRule{handshake.TypeClientHello, cfg.initialEpoch, true, false},
handshakeCachePullRule{handshake.TypeServerHello, cfg.initialEpoch, false, false},
handshakeCachePullRule{handshake.TypeFinished, cfg.initialEpoch + 1, false, false},
)
var err error
state.localVerifyData, err = prf.VerifyDataClient(state.masterSecret, plainText, state.cipherSuite.HashFunc())
if err != nil {
return nil, &alert.Alert{Level: alert.Fatal, Description: alert.InternalError}, err
}
}
pkts = append(pkts,
&packet{
record: &recordlayer.RecordLayer{
Header: recordlayer.Header{
Version: protocol.Version1_2,
Epoch: 1,
},
Content: &handshake.Handshake{
Message: &handshake.MessageFinished{
VerifyData: state.localVerifyData,
},
},
},
shouldEncrypt: true,
resetLocalSequenceNumber: true,
})
return pkts, nil, nil
}