Flare-On 13 Part 2: A Patched SHA-256d, a Vanity Volume Serial, and a Hand-Rolled Huffman Decoder
A 32-round SHA-256 whose Ch and Maj functions were rewritten, keyed off a 32-bit volume serial that spells ICE COLD in leetspeak, and a 264-byte RC4 keystream reused as a two-time pad before five JPEGs come back out of a custom canonical Huffman bitstream.