To play and/or record most, if not all, of the videos on this site, you do NOT NEED A TOKEN. Just find the m3u8 version by using iOS as UA.
example:
Code:
ffplay -i 'http://123.30.104.190:10908/vivo/_definst_/mp4:video/couple_and_troubl/couple_and_trouble_001_1_low.mp4/playlist.m3u8'
However, your question, I believe pertains to the token and how you can decrypt it. I'm not an expert on encryption/decryption, but I think the hash used was MD5-based. In general, to decrypt a token, you'll have to know what encryption was used and in many cases what key was used to encrypt the token. There are folks "experts" on this forum that are far more knowledgeable that I could ever be. KSV, being one of them
So hopefully someone could shed some light on how it's done (although I doubt it). Note that there is no "one-size-fits-all" when it comes to finding and decrypting tokens, so I would not expect a "how to guide" on how to decrypt tokens, b/c there are several ways you can skin a cat
Good Luck!