Is it possible to add a header tag to handle the canonical link issue for search engiens within the logic of a custom module?

We have a module that renders content from a central repository onto multiple pages within a site.  Depending on the page on which an item is rendered it may or may not be what we deem as the canonical home for it, as one artcile could show in two locations, we want to apply logic within a custom module that would set the link tag accordingly.

Is there or what is the best way to add header level tags from within a module's code?

Thanks.  I guess I'm more looking for the DNN code that is required to create the actual HEAD tag entry from a module if that is possible.  I know what the canonical tag needs to be but we need a means to add it tothe HEAD section dynamically based on wha tthe module loads.