module WEBrick::HTTPAuth

def _basic_auth(req, res, realm, req_field, res_field, err_type,
                block) # :nodoc:
  user = pass = nil
  if /^Basic\s+(.*)/o =~ req[req_field]
    userpass = $1
    user, pass = userpass.unpack("m*")[0].split(":", 2)
  end
  if block.call(user, pass)
    req.user = user
    return
  end
  res[res_field] = "Basic realm=\"#{realm}\""
  raise err_type
end

def basic_auth(req, res, realm, &block) # :yield: username, password
  _basic_auth(req, res, realm, "Authorization", "WWW-Authenticate",
              HTTPStatus::Unauthorized, block)
end

def proxy_basic_auth(req, res, realm, &block) # :yield: username, password
  _basic_auth(req, res, realm, "Proxy-Authorization", "Proxy-Authenticate",
              HTTPStatus::ProxyAuthenticationRequired, block)
end