Linking directly to Adhoc Report Builder and specific data source

Does anyone know how to link directly to the Adhoc Report Builder, and if possible a specific data source within the builder. Currently, when I try to do this from an outside link, it brings me to the logon page. I would like to be able to pass the credentials through without the user seeing the logon screen. This seems like it should be fairly straight forward, but I am having a hard time getting it working and have found very little reference to how to do it correctly.

Any help would be greatly appreciated.

Thanks,

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