Cloak/internal/client/TLS.go
2019-08-02 18:03:08 +01:00

42 lines
1.2 KiB
Go

package client
import (
"encoding/binary"
"github.com/cbeuw/Cloak/internal/util"
)
type Browser interface {
composeClientHello(*State) ([]byte, []byte)
}
func makeServerName(serverName string) []byte {
serverNameListLength := make([]byte, 2)
binary.BigEndian.PutUint16(serverNameListLength, uint16(len(serverName)+3))
serverNameType := []byte{0x00} // host_name
serverNameLength := make([]byte, 2)
binary.BigEndian.PutUint16(serverNameLength, uint16(len(serverName)))
ret := make([]byte, 2+1+2+len(serverName))
copy(ret[0:2], serverNameListLength)
copy(ret[2:3], serverNameType)
copy(ret[3:5], serverNameLength)
copy(ret[5:], serverName)
return ret
}
// addExtensionRecord, add type, length to extension data
func addExtRec(typ []byte, data []byte) []byte {
length := make([]byte, 2)
binary.BigEndian.PutUint16(length, uint16(len(data)))
ret := make([]byte, 2+2+len(data))
copy(ret[0:2], typ)
copy(ret[2:4], length)
copy(ret[4:], data)
return ret
}
// ComposeClientHello composes ClientHello with record layer
func ComposeClientHello(sta *State) ([]byte, []byte) {
ch, sharedSecret := sta.Browser.composeClientHello(sta)
return util.AddRecordLayer(ch, []byte{0x16}, []byte{0x03, 0x01}), sharedSecret
}