This is the error you might get while configuring Openswan. As I received this error when I was configuring openswan to connect my sonicwall vpn.
#1: Informational Exchange message must be encrypted
Make sure you have set these parameters in your Sonicwall
IKE (Phase 1) Proposal
DH Group: Group 5 (not 2)
Life Time: 28800
Ipsec (Phase 2) Proposal
Check “Enable Perfect Forward Secrecy”
DH Group: Group 5
Life Time (seconds) 28800
Check these parameters in your linux machine
# vi /etc/ipsec.conf
esp=3DES-SHA1 # protocol used for authentication in sonicwall
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