Download key protected m3u8

[bloodhand]

Hello!

This is the original link for the video: http://protvplus.ro/produs/apropo-tv...decembrie-2016.

I tried the following ffmpeg batch with no success:

ffmpeg -i http://cdn.drm.protv.ro/protvplus.ro/2017/01/12/43c7a0a664d7d0fa805d26a047feda05.ism/43c7a0a664d7d0fa805d26a047feda05.m3u8 -c copy -absf aac_adtstoasc video.mp4

The error I get is:

HTTP ERROR 403 Forbidden
Unable to open key file http://drmapi.protv.ro/keys/get/protvplus.ro/61307737

I guess I have to download the key file and put it into the folder along with ffmpeg.exe, but I have no idea how to do this...

Thanks in advance.