OpenSSL 1.1 will be released soon, and Nmap currently fails to build with it. There are 2 parts of this task:

1. Fix the build, using preprocessor macros when necessary to ensure that it still builds with the OpenSSL 1.0.x branches.
2. Research and document any functional changes to the way Nmap does things. Issues in the past have been: removal of SSLv2, needing backwards-compatible handshake methods, addition of SNI-related calls.

References:

• FTBFS bug on Debian
• OpenSSL API changes in 1.1