@denandz Thanks for this contribution! It looks like a fun and exciting addition to our program. Before we can review it, please ensure that it passes our build test. Specifically, you should guard sections of code that depend on OpenSSL with #ifdef HAVE_OPENSSL.

@dmiller-nmap I double checked the code and it looks like all the relevant guards are there. The build test seems to have a problem locating DTLS_client_method(). What version of openssl is the build using? SSL_CTX_set_alpn_protos() is also only available in more recent versions of openssl. I guess I could attempt to get some voodoo working to detect the openssl version and add in additional guards? Please advise. Roger that, added in checks for the openssl version.

Also, in the travis-ci non-ssl builds are being built with openssl. The './configure $SSL_FLAG' doesn't seem to work as expected. On my system:

$ export SSL_FLAG="--without-ssl"
$ ./configure $SSL_FLAG
{snip}
Configured with: ndiff zenmap nping openssl lua ncat
Configured without: localdirs nmap-update
Type make (or gmake on some *BSD machines) to compile.
$

Similar is reflected in the travis-ci build logs. (EG: https://travis-ci.org/nmap/nmap/jobs/142393838)

@denandz Thanks for pointing that out about the travis builds! I just pushed a change to correctly configure without OpenSSL. Hope to be able to review this pull soon.

@dmiller-nmap any update on the pull ?

McFly?

Thanks @dmiller-nmap! You can use Denis Andzakovic as the credit name in the change log. Thanks for merging these features ^_^