Reverse-engineering efforts to generate license keys for Raspberry Pi hardware video decoding

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README.md

raspi-keygen

This is an effort to reverse-engineer the Raspberry Pi license key check for MPEG-2 and VP1 hardware video encoding.

Patch

A bootloader patch that disables licensing checks was posted to reddit by /u/fuck_the_mpeg_la on 03-03-2017:

cd /boot
cp start.elf start.elf_backup && \
 perl -pne 's/\x47\xE9362H\x3C\x18/\x47\xE9362H\x3C\x1F/g' < start.elf_backup > start.elf

Some initial analysis was done by q3k on Hacker News:

Yes, it seems to patch a licensing function at 0xEC95FD4 [1] to always return 1, by patching the jump at 0xEC95FE2 (that should be only taken for the always-allowed H263 codec) to always be taken, thus always allowing all codecs.