Tiger Cryptography
This code comes from the reference implementation of the Tiger cryptographic hash function. The only modification made is to pull out the data types and the api into a header file (this file, tiger.h). The reference implementation is available at:
http://www.cs.technion.ac.il/~biham/Reports/Tiger/
From that page:
Tiger has no usage restrictions nor patents. It can be used freely, with the reference implementation, with other implementations or with a modification to the reference implementation (as long as it still implements Tiger). We only ask you to let us know about your implementation and to cite the origin of Tiger and of the reference implementation.