Secure Sockets Layer (SSL) Classes

Enabling and Disabling SSL Support

When building Qt from source, the configuration system checks for the presence of the openssl/opensslv.h header provided by source or developer packages of OpenSSL.

By default, an SSL-enabled Qt library dynamically loads any installed OpenSSL library at run-time. However, it is possible to link against the library at compile-time by configuring Qt with the -openssl-linked option.

When building a version of Qt linked against OpenSSL, the build system will attempt to link with libssl and libcrypt libraries located in the default location on the developer's system. This location is configurable: set the OPENSSL_LIBS environment variable to contain the linker options required to link Qt against the installed library. For example, on a Unix/Linux system:

 ./configure -openssl-linked OPENSSL_LIBS='-L/opt/ssl/lib -lssl -lcrypto'

To disable SSL support in a Qt build, configure Qt with the -no-openssl option.