Oh, you have a "discrete" TPM in your machine and this means your disk encryption is "safe" if someone steals it, right?
We're very familiar with the many projects in which Raspberry Pi hardware is used, from giving old computers a new lease of life through to running the animated displays so beloved by retailers. But cracking BitLocker? We doubt the company will be bragging too much about that particular application.
This isn't really "cracking"; the Pi is simply used as a snoop to capture the key after the TPM releases it. Which it will do, if its happy with the hardware configuration and such (e.g. same disk, nobody's tampered with the machine that it knows about, etc.)
Calling this a "hack" is, well.... wrong.
An "encrypted" disk in a machine that has a TPM in it, and no password, simply means if you steal only the disk you can't decrypt it because you don't have the key which is in the TPM. If you steal the entire machine including the TPM and disk and can convince the TPM it has not been compromised (which, if nothing has been removed or added, it hasn't) it will release the key and since they are two pieces of hardware separated by a wire you can pick it off quite-trivially.
The correct answer is "don't do that if this is your threat model"; use a password along with the "built-in" TPM. Now the TPM only has part of the key and you have the rest, which can't be snooped off the hardware because it is in your head.
(The same applies if you use a CAC-style card or similar authentication device; if you don't have it you have no way to know what that part of the key is.)
It is possible to design a device that has "tamper detection" hardware (e.g. a pin switch that opens if the case is opened to get to the drive) and which "trips" the TPM if it detects chassis intrusion so that it refuses to release the keying (or erases itself) but as far as I know none of the laptops out there in common use have that addition. Most server boards of reasonably recent vintage have a connector for it but of course your case has to have the appropriate switch(es) in the correct places and this would still not help if, for example, someone knows its there and cuts through the metal away from the switch.
A "hack" would involve, for example, finding the IV and keying on the disk somewhere you can read it. Now you need nothing other than the drive itself because you can obtain the IV and key -- and with both you can decrypt the device's data.
This is not a "hack", it is merely clever interception of data that the system's security chip was willing to give up, and said hardware wasn't tricked into doing it either.
If you're not going to put a PIN/Password on your laptop Bitlocker you might as well run with it turned off (and get the performance improvement from not doing the encryption in the CPU at all since in most instances Windows refuses to use the OPAL hardware encryption on the disk itself anyway as they claim they're not confident it is actually secure.)