the tar file does not contain configure

[wefa]

The tar file does not contain configure and can therefore not be built as described in README.

[royhills]

Where is the tar file coming from? The ike-scan git repo shouldn't contain a tar file, and it doesn't contain "configure" either as that's a generated file. The README should say this about installing. The "autoreconf --install" bit generates "configure":

ike-scan uses the standard GNU autoconf and automake tools, so installation is the normal process:

Run git clone https://github.com/royhills/ike-scan.git to obtain the project source code
Run cd ike-scan to enter source directory
Run autoreconf --install to generate a viable ./configure file
Run ./configure or ./configure --with-openssl to use the OpenSSL libraries
Run make to build the project
Run make check to verify that everything works as expected
Run make install to install (you'll need root or sudo for this part)