Let's assume that a legitimate torrent file has been safely and successfully downloaded over HTTPS and perhaps even OpenPGP verification was used to verify the integrity of the torrent file.
How good are torrent clients against attackers who want to add malicious content to the download?
Does torrent clients only catch disruption due to network failure or any kind of of attack?
Does torrent clients only use SHA1 or a stronger hash algorithm, were fewer people argue whether its still secure or not, such as SHA256?
(I am NOT asking about any privacy/piracy/legal aspects here.)