The Shrew Soft Client has been reported to work with StrongSWAN software. If you have experience with this gateway type and use it in conjunction with the Shrew Soft VPN Client, please consider contributing a Wiki howto document. For more details on how to contribute, please contact us. [mgrooms@dev ~/wiki]$ cat HowTo_pfSense.trac The Shrew Soft VPN Client has been tested with pfSense products to ensure interoperability. The project hosts its own documentation that can be used to configure the gateway and Shrew Soft VPN Client.
Please see the following document from the pfSense Wiki website.