HOWTO.dual.openssl

############################################################################
#
# OpenSSL dual versions
#
# Works with CentOS 7
#
############################################################################
#
# Add in alternative OpenSSL support into /opt/openssl.  /opt/openssl is
# chosen instead of the default of /usr/local so that existing utilities
# continue to use the original version of OpenSSL and so only specific
# applications that requires the newer version of OpenSSL will pick up the
# new code.
#
# Download latest stable version of openssl.X.Y.Z.tar.gz from
# https://www.openssl.org/source/

tar zxovf openssl.X.Y.Z.tar.gz
cd openssl.X.Y.X
./config --prefix=/opt/openssl --openssldir=/opt/openssl
make
sudo make install_sw

# The following should not clash the existing OpenSSL lib*.so.1.0 usage unless
# the previous OpenSSL version is 1.1.0 or later.
# It just makes things for running executables a lot simpler.
sudo cp /opt/openssl/lib/lib*.so.1.1 /lib64
cd ..

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#
# libcoap build with updated OpenSSL
#
############################################################################

# Get the latest libcoap
git clone https://github.com/obgm/libcoap.git

# Build code
cd libcoap
./autogen.sh
# Update --enable- / --disable- options as appropriate
# libcoap libraries are put into /usr/lib64 for ease of linking
PKG_CONFIG_PATH=/opt/openssl/lib/pkgconfig ./configure --libdir=/usr/lib64 \
  --with-openssl --enable-tests --enable-examples --disable-doxygen \
  --disable-manpages
make
sudo make install
cd ..