Linux From Scratch - Version 9.0

Chapter 6. Installing Basic System Software

6.50. OpenSSL-1.1.1c

The OpenSSL package contains management tools and libraries relating to cryptography. These are useful for providing cryptographic functions to other packages, such as OpenSSH, email applications and web browsers (for accessing HTTPS sites).

Approximate build time: 2.3 SBU
Required disk space: 147 MB

6.50.1. Installation of OpenSSL

First, fix a problem identified upstream: 

sed -i '/\} data/s/ =.*$/;\n    memset(\&data, 0, sizeof(data));/' \
  crypto/rand/rand_lib.c

Prepare OpenSSL for compilation: 

./config --prefix=/usr         \
         --openssldir=/etc/ssl \
         --libdir=lib          \
         shared                \
         zlib-dynamic

Compile the package: 

make

To test the results, issue: 

make test

Install the package: 

sed -i '/INSTALL_LIBS/s/libcrypto.a libssl.a//' Makefile
make MANSUFFIX=ssl install

If desired, install the documentation: 

mv -v /usr/share/doc/openssl /usr/share/doc/openssl-1.1.1c
cp -vfr doc/* /usr/share/doc/openssl-1.1.1c

6.50.2. Contents of OpenSSL

Installed programs: c_rehash and openssl
Installed libraries: libcrypto.{so,a} and libssl.{so,a}
Installed directories: /etc/ssl, /usr/include/openssl, /usr/lib/engines and /usr/share/doc/openssl-1.1.1c

Short Descriptions

c_rehash

is a Perl script that scans all files in a directory and adds symbolic links to their hash values.

openssl

is a command-line tool for using the various cryptography functions of OpenSSL's crypto library from the shell. It can be used for various functions which are documented in man 1 openssl.

libcrypto.so

implements a wide range of cryptographic algorithms used in various Internet standards. The services provided by this library are used by the OpenSSL implementations of SSL, TLS and S/MIME, and they have also been used to implement OpenSSH, OpenPGP, and other cryptographic standards.

libssl.so

implements the Transport Layer Security (TLS v1) protocol. It provides a rich API, documentation on which can be found by running man 3 ssl.