如何在加密之前在tcpdump中查看传出的ESP数据包

I have a setup having Ipsec Tunnel between two end systems. When I capture packets on outgoing interface e.g eth0 I can only see encrypted ESP packets going out of my system. I have to go and look at the receiving end to see what was actually transmitted i.e on the receiving end I can see packets after decryption. similarly for the ack sent by receiver. How it works actually in the linux kernel ? Is there a way to see the packets on sender side in tcpdump before they get encrypted ?I have a setup having Ipsec Tunnel between two