I believe Nikon and Canon both (Canon certainly) absolutely have had this available for at least a decade or more, with hardware modules for their cameras that

I believe Nikon and Canon both (Canon certainly) absolutely have had this available for at least a decade or more, with hardware modules for their cameras that were able to cryptographically sign raw images to attest that that signed data was direct from the sensor. Was a huge concern once digital cameras became sophisticated enough to use in law enforcement.