SUSE: 2021:0194-1 Moderate: Resolution for Stunnel Security Vulnerability

This update for stunnel fixes the following issues: Security issue fixed: - The "redirect" option was fixed to properly handle "verifyChain = yes" (bsc#1177580). Non-security issues fixed: - Fix startup problem of the stunnel daemon (bsc#1178533) - update to 5.57: * Security bugfixes * New features - New securityLevel configuration file option. - Support for modern PostgreSQL clients - TLS 1.3 configuration updated for better compatibility. * Bugfixes - Fixed a transfer() loop bug. - Fixed memory leaks on configuration reloading errors. - DH/ECDH initialization restored for client sections. - Delay startup with systemd until network is online. - A number of testing framework fixes and improvements. - update to 5.56: - Various text files converted to Markdown format.