Example: NTLM Authentication with NetHTTP

uri = URI('https://host.com/ews/exchange.asmx')
user = ''
passwd = ''

Net::HTTP.start(uri.host, uri.port, :use_ssl => uri.scheme == 'https') do |http|

  request = Net::HTTP::Get.new(uri.request_uri)
  t1 = Net::NTLM::Message::Type1.new()
  request['Authorization'] = 'NTLM ' + t1.encode64
  response = http.request(request)

  if /\A(NTLM|Negotiate) (.+)\z/ =~ response.header['www-authenticate']
    msg = $2
  end

  t2 = Net::NTLM::Message.decode64(msg)

  t3 = t2.response({:user => user, :password => passwd}, {:ntlmv2 => true})

  request['Authorization'] = 'NTLM ' + t3.encode64
  response = http.request(request)

  puts response.msg
  response.header.each_header do |h| puts h.inspect + "  " + response.header[h] end
  puts response.body

end

net_http_rubyntlm.rb

uri = URI('https://host.com/ews/exchange.asmx')
user = ''
passwd = ''

Net::HTTP.start(uri.host, uri.port, :use_ssl => uri.scheme == 'https') do |http|

  request = Net::HTTP::Get.new(uri.request_uri)
  t1 = Net::NTLM::Message::Type1.new()
  request['Authorization'] = 'NTLM ' + t1.encode64
  response = http.request(request)

  if /\A(NTLM|Negotiate) (.+)\z/ =~ response.header['www-authenticate']
    msg = $2
  end

  t2 = Net::NTLM::Message.decode64(msg)

  t3 = t2.response({:user => user, :password => passwd}, {:ntlmv2 => true})

  request['Authorization'] = 'NTLM ' + t3.encode64
  response = http.request(request)

  puts response.msg
  response.header.each_header do |h| puts h.inspect + "  " + response.header[h] end
  puts response.body

end