mirror of
https://github.com/cbeuw/Cloak.git
synced 2024-11-11 13:11:03 +00:00
71 lines
1.8 KiB
Go
71 lines
1.8 KiB
Go
package client
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"github.com/cbeuw/Cloak/internal/util"
|
|
"net"
|
|
|
|
log "github.com/sirupsen/logrus"
|
|
)
|
|
|
|
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
|
|
}
|
|
|
|
func PrepareConnection(sta *State, conn net.Conn) (sessionKey []byte, err error) {
|
|
|
|
clientHello, sharedSecret := composeClientHello(sta)
|
|
_, err = conn.Write(clientHello)
|
|
if err != nil {
|
|
return
|
|
}
|
|
log.Trace("client hello sent successfully")
|
|
|
|
buf := make([]byte, 1024)
|
|
log.Trace("waiting for ServerHello")
|
|
_, err = util.ReadTLS(conn, buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
serverRandom := buf[11:43]
|
|
sessionKey = decryptSessionKey(serverRandom, sharedSecret)
|
|
_, err = util.ReadTLS(conn, buf)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
return sessionKey, nil
|
|
|
|
}
|