TWEAKABLE HASH FUNCTION IN HASH BASED SIGNATURE SCHEMES

The present relates to a method for implementing a tweakable hash function to optimize hardware resource utilization used in hash-based signature schemes for signing a digital message. The method comprises :- i) Providing input data derived from the digital message to be signed;- ii) Segmenting the input data in chunk blocks;- iii) Generating an input sequence based on the chunk blocks, said input sequence being suitable for being provided to a hash computing engine, said computing engine comprising input blocks to receive the input sequence;- iv) Computing a tweakable hash function (T2) with a hash computing engine based on the input sequence to generate the tweaked hash value;The method is characterized in that the tweakable hash function is defined to sort the chunk blocks.The invention further relates to a device comprising a circuit arranged for executing a method according to the invention.