Authentic way to access quote for admin and frontend area

I am working on shipping module where i need to fetch quote subtotal in both area frontend as well as admin order create.

I am using MagentoCheckoutModelSession to get the quote subtotal but when i try to check in admin no value return for quote.

Also tried MagentoQuoteModelQuote method getBaseSubTotal return nothing.

Any other solution where we can use same code for both area.