Indy currently supports OpenSSL up to 1.0.2. OpenSSL 1.1.0 makes a number of major API changes that break TIdSSLIOHandlerSocketOpenSSL. Removing/renaming functions, changing/obscuring structures, changing the DLL filenames, etc. Indy needs to either have TIdSSLIOHandlerSocketOpenSSL recognize 1.1.0+ and adjust itself accordingly, or else define a whole new IOHandler just for 1.1.0+.
Also, in order to support TLS 1.3, Indy needs to support OpenSSL 1.1.1+, as TLS 1.3 will NOT be added to OpenSSL 1.0.2 or 1.1.0.
The OpenSSL devs will stop supporting OpenSSL 1.0.2 on Dec 31 2019, and 1.1.0 on Sept 11 2019.
UPDATE: as of 07-Sep-2021, OpenSSL 3.0.0 has been released, which is largely backwards compatible with 1.1.x, but does make some additional API changes. Refer to https://www.openssl.org/docs/man3.0/man7/migration_guide.html
Indy currently supports OpenSSL up to 1.0.2. OpenSSL 1.1.0 makes a number of major API changes that break
TIdSSLIOHandlerSocketOpenSSL. Removing/renaming functions, changing/obscuring structures, changing the DLL filenames, etc. Indy needs to either haveTIdSSLIOHandlerSocketOpenSSLrecognize 1.1.0+ and adjust itself accordingly, or else define a whole new IOHandler just for 1.1.0+.Also, in order to support TLS 1.3, Indy needs to support OpenSSL 1.1.1+, as TLS 1.3 will NOT be added to OpenSSL 1.0.2 or 1.1.0.
The OpenSSL devs will stop supporting OpenSSL 1.0.2 on Dec 31 2019, and 1.1.0 on Sept 11 2019.
UPDATE: as of 07-Sep-2021, OpenSSL 3.0.0 has been released, which is largely backwards compatible with 1.1.x, but does make some additional API changes. Refer to https://www.openssl.org/docs/man3.0/man7/migration_guide.html