root@s0565b4ce ~# echo | openssl s_client -connect '1.1.1.1:853' 2>/dev/null | openssl x509 -pubkey -noout | openssl pkey -pubin -outform der | openssl dgst -sha256 -binary | openssl enc -base64
RKlx+/Jwn2A+dVoU8gQWeRN2+2JxXcFkAczKfgU8OAI=
root@s0565b4ce ~# echo | openssl s_client -connect '8.8.8.8:853' 2>/dev/null | openssl x509 -pubkey -noout | openssl pkey -pubin -outform der | openssl dgst -sha256 -binary | openssl enc -base64
z9OBIUcDlAUM7Qyb7fPN3OuMIIy2l4lqtGwO+/dTj4o=