Is there a way to check the losslessness of a FLAC file in Linux?

Let me explain my question with greater detail: I know FLAC is a lossless audio format **with respect to the original file;** this is, any piece of audio encoded with FLAC will be preserved completely. But say I got an CD album in MP3 format (which is, of course, lossy) and then decide to re-encode it in FLAC and give this "lossless" version to a friend. How does he/she know that the file received from me is not an exact copy of the CD album but a camouflaged lossy copy? I've read something about it and it seems there is some app for Windows which identifies this fake FLACs but I haven't found anything like that for Linux. So my question is: Is there a way to tell real FLACs from fake ones in Linux?