allow_ctrl_v.js

var ctrlKey = 17,
    ctrlDown = false,
    vKey = 86,
    allowCtrlPaste,
    allowPaste,
    captureCtrl,
    releaseCtrl;

allowCtrlPaste = function(e){
  if (ctrlDown && e.keyCode == vKey) {
    e.stopImmediatePropagation();
    return true;
  }
};

allowPaste = function(e){
  e.stopImmediatePropagation();
  return true;
};

captureCtrl = function(e){
  if (e.keyCode == ctrlKey) {
    ctrlDown = true;
  }
};

releaseCtrl = function(e){
  if (e.keyCode == ctrlKey) {
    ctrlDown = false;
  }
};

document.addEventListener('keydown', allowCtrlPaste, true);
document.addEventListener('keydown', captureCtrl, true);
document.addEventListener('keyup', releaseCtrl, true);
document.addEventListener('paste', allowPaste, true);