Howto switch to OpenSSL 1.0 for TLS Connections

Debian and Ubuntu

First of all you need to make and install OpenSSL 1.0.2r from source.

sudo apt install build-essential checkinstall zlib1g-dev -y

cd /usr/src


tar -xvzf openssl-1.0.2r.tar.gz

cd openssl-1.0.2r

./config -d --prefix=/usr/local/ssl --openssldir=/usr/local/ssl shared zlib

make test

make install

nano /etc/

Add this line and save:


sudo ldconfig -v

mv /usr/bin/c_rehash /usr/bin/c_rehash.BEKUP
mv /usr/bin/openssl /usr/bin/openssl.BEKUP

export PATH=$PATH:/usr/local/ssl/bin

Link binaries to path:

sudo ln -s /usr/local/ssl/bin/c_rehash /usr/bin/c_rehash
sudo ln -s /usr/local/ssl/bin/openssl /usr/bin/openssl


sudo shutdown -r now

Check OpenSSL path, should return '/usr/bin/openssl'.

which openssl

Check OpenSSL version, should return 'OpenSSL 1.0.2r 26 Feb 2019'.

openssl version

Modify '/usr/src/kamailio/src/modules/tls/makefile'.

Change this:

ifneq ($(SSL_BUILDER),)
    DEFS += $(shell $(SSL_BUILDER) --cflags)
    LIBS += $(shell $(SSL_BUILDER) --libs)
    DEFS += -I$(LOCALBASE)/ssl/include
    LIBS += -L$(LOCALBASE)/lib -L$(LOCALBASE)/ssl/lib \
            -L$(LOCALBASE)/lib64 -L$(LOCALBASE)/ssl/lib64 \
            -lssl -lcrypto
    # NOTE: depending on the way in which libssl was compiled you might
    #       have to add -lz -lkrb5   (zlib and kerberos5).
    #       E.g.: make TLS_HOOKS=1 TLS_EXTRA_LIBS="-lz -lkrb5"

To this:

DEFS+=  -I/usr/local/ssl/include
LIBS+=  -L/usr/local/ssl/lib \
        -lssl -lcrypto

Make clean, make and make install:

cd /usr/src/kamailio/src/modules/tls
make clean
make install