"mruby-tls-openssl" is a TLS library for mruby using OpenSSL.
Though very small number of APIs are implemented currently, you can write a HTTP2 client with it.

• TLS.new(host, opts={})
  • Open a new TLS connection to host. host can be either a hostname (String) or a TCP socket (TCPSocket).
  • Supported keys in opts:
    • :alpn => str
      • send str as a protocol for ALPN
    • :certs => str
      • pathname of the file contains trusted root CA certificate(s)
    • :identity => str
      • a server's identity expected
    • :ignore_certificate_validity => boolean
      • ignore "Not Before" and "Not After" fields of certificates
    • :port => Integer
      • port number (used only when host is a string)
    • :sni => false (default) | true | String
      • use Server Name Indication (SNI)
        • false : don't send SNI extention
        • true : send opts[:identity] or host as a server name
        • String : send it as a server name
    • :version => str
      • TLS version: one of "TLSv1.0", "TLSv1.1", "TLSv1.2", or "any"
• TLS#read(len=)
  • Read len bytes from TLS connection.
• TLS#write(str)
  • Write str to TLS connection.
• TLS#close
  • Close TLS connection

# verify server's identity
tls = TLS.new "github.com", { :port => 443, :certs => "digicert.crt", :identity => "github.com" }
tls.write "GET / HTTP/1.1\r\nHost: github.com\r\nConnection: close\r\n\r\n"
p tls.read
tls.close

If you want to use TLS ALPN Extension, build and install OpenSSL 1.0.2 (or later) into openssldir directory:

% cd mruby-tls-openssl
% curl https://www.openssl.org/source/openssl-1.0.2a.tar.gz | tar xzf -
% cd openssl-1.0.2a
% ./config --openssldir=`pwd`/../openssldir no-shared no-threads
% make
% make install

then build mruby.

To try LibreSSL, install it to openssldir:

% cd mruby-tls-openssl
% curl -O http://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.1.4.tar.gz
% tar xzf libressl-2.1.4.tar.gz
% cd libressl-2.1.4
% ./configure --disable-shared --prefix=`pwd`/../openssldir
% make
% make install

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