The Shrew Soft VPN Client for Unix is a free IPsec Client for FreeBSD, NetBSD, and Linux based operating systems. It can be used to communicate with systems running ipsec-tools. The Unix client utilizes the IPsec kernel support included with the operating system, and comes with the complete Internet Key Exchange daemon and client front end application source code. A Windows version is also available.
License: OSI Approved
Changes:
Diffie Hellman group setup was cleaned up. Portions of the configuration exchange code were rewritten. Non-NUL-terminated string buffers were fixed.
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