This page has information about building and compiling Openswan from source code.
From Tarballs
From CVS
Common Building Problems
These problems, and other common problems, are in the FAQ.
- gmp.h: No such file or directory
Openswan needs the GMP (GNU Multi-Precision) library for the large integer calculations it uses in public key cryptography. This error message indicates a failure to find the header files for the library. The GMP library is included in most Linux distributions. Typically, there are two RPMs, libgmp and libgmp-devel, You need to install both, either from your distribution CDs or from your vendor's web site.
- Slackware: Look in the L directory of your Slackware distribution.
- RPM / SuSE 9.1: Look for gmp-<Version> .
About the Openswan kernel patches
The are 2 openswan patches.
- nat-t patch: provides NATTraversal support for 2.4 Linux kernels
- klips patch: provides the KLIPS IPSEC stack for stock 2.4 kernels. If you are using RHEL3, there is already an IPSEC stack in the kernel named NETKEY. It is a backport(done by RedHat) of the 2.6 Linux kernels IPSEC stack
