Hi, I am trying to implement a client server program over SSL through systemd. Here I have a TCP systemd socket (listening on a predefined port) and its associated service.
systemd socket file:- # cat /usr/lib/systemd/system/test_ssl.socket [Unit] Description=Test socket [Socket] ListenStream=2000 Accept=true MaxConnections=900 [Install] WantedBy=sockets.target systemd service file:- # cat /usr/lib/systemd/system/test_ssl@.service [Unit] Description= Test Service Requires=test_ssl.socket [Service] ExecStart=/home/SSL/server StandardInput=socket KillMode=process [Install] WantedBy=multi-user.target The service file invoke the binary /home/SSL/server. Here is it a very simple client server program, where 1. Server binds and listens on a port number. 2. Client first connects to server with normal connect (server will do accept) 3. Once it gets the fd, client does the SSL_connect over same connection. (server will do SSL_accept) 4. After that it will be SSL_read & SSL_write. Once, I start the systemd socket I can see the systemd starts listening on port 2000. # systemctl start test_ssl.socket # netstat -an | grep 2000 tcp6 0 0 :::2000 :::* LISTEN Post than when executing client, SSL_conect fails. # ./client localhost 2000 OpenConnection succedeed. << normal connect succeeds. SSL_connect failed. 140691172779952:error:1408F10B:SSL routines:SSL3_GET_RECORD:wrong version number:s3_pkt.c:365: Here client is able to do normal connect, post that SSL_connect fails. This client server program works well outside of systemd. Do I need to add some extra steps to get this working? Any help or reference would be appreciated. Thanks & Regards,