How to Access Master Page Controls from page.aspx doesn't inherit from master

[SerpentKiss2010]

i have master page called (Master.master), content page called (Home.aspx) and two independent pages (Login.aspx) and (Registration.aspx)..

master page have three linkbuttons (btnSigninMaster) (btnSignupMaster) and (btnSignOutMaster)

in (btnSigninMaster) click .. ModalPopup (LoginModalPopup) appears that contains (iFrame src="Login.aspx"),
in (btnSignupMaster) click .. ModalPopup (RegModalPopup) appears that contains (iFrame src="Registration.aspx")

<-- Login Popup Code -->

    <%-- LoginModalPopup --%>
    <Ajax:ModalPopupExtender ID="LoginModalPopup" runat="server"
    BehaviorID="mdlPopupLogin"
    PopupControlID="pnlPopupLogin"
    TargetControlID="btnSigninMaster"
    DropShadow="true" BackgroundCssClass="modalBackground">
    </Ajax:ModalPopupExtender>
    <%-- End-Of LoginModalPopup --%>

    <%-- Login Panel --%>
    <div id="pnlPopupLogin" style="">

    <div class="popup_Container">
               <div class= "PopupTitlebar" id="divSigninTitleBar">
                    <div class="TitlebarLeft" 
                        style="font-family: Verdana; color: #FFFFFF; font-size: small; font-weight: bold;">
                     Log-in
                    </div>

                    <div class="TitlebarRight" onclick=" $find('mdlPopupLogin').hide(); return false;">
            
                    </div>
               </div>

        <div class="demo">
        
        <%-- Login iFrame of Membership/Login.aspx --%>

        <iframe id="iFrameLogin" src="Membership/Login.aspx" runat="server" frameborder="0" scrolling="no" 
          marginwidth="0" marginheight="0" width="380" height="90" ></iframe>
        </div>

    </div>
   </div>
    <%-- End of Login Panel --%>

<-- Registration Popup Code -->

    <%-- RegistrationModalPopup --%>
    <Ajax:ModalPopupExtender ID="RegModalPopup" runat="server"
    BehaviorID="mdlPopupReg"
    PopupControlID="pnlPopupRegistration"
    TargetControlID="btnSignupMaster"
    BackgroundCssClass="modalBackground"
    DropShadow="true">
    </Ajax:ModalPopupExtender>
    <%-- End-Of RegistrationModalPopup --%>

    <%-- Registration Panel --%>
    <div id="pnlPopupRegistration" style="">
    
     <div class="popup_Container">
               <div class= "PopupTitlebar">
                    <div class="TitlebarLeft" 
                        style="font-family: Verdana; color: #FFFFFF; font-size: small; font-weight: bold;">
                     Registration
                    </div>

                    <div class="TitlebarRight" onclick="ClearAllData(); $find('mdlPopupReg').hide(); return false;" >
                 
                    </div>
               </div>
               
        <!-- Controls of Registration Form -->
        <div class="demo">

        <iframe id="iFrameRegistration" src="Membership/Registration.aspx" runat="server" 
                frameborder="0" height="575" scrolling="no" width="760" marginwidth="0" marginheight="0">
        
        </iframe>

        </div>
     </div>
    
    </div>
    <%-- End-Of Registration Panel --%>

my Issue is
1- i want make btnSigninMaster, btnSignupMaster, and mdlPopupLogin disappear from Master page when Login Succeeded, and show btnSignOutMaster.

2- make mdlPopupReg disappear from master page when Signup Succeeded ).

( Login.aspx has btnLogin that i want execute previous functionality (problem) when click on it )
also,
Registration.aspx has btnCreateAccount

Thank you for your help ....