additive hash function

Question

Do functions with the following properties exists for x being arbitrary stream of bytes:

op(f(x1), f(x2))=f(x1+x2) and op(f(x1), f(x2))!=f(x2+x1) given that x1!=x2 where plus denotes concatenation and op is an easily computable operation
f(x) is fixed length of about 160-512 bytes
f does not need to be hard to revert, but should be useful at finding transmission errors or duplicates.

Could you provide any names/articles/pointers?

score 1 · Answer 1 · answered Jan 11 '19 at 22:54

1

Try the CRC hash; it has this property. You can also look at Merkle tree hashing.

answered Jan 11 '19 at 22:54

D.W.

1 Answers1