On 6/19/18, Stephan Beal <sgb...@googlemail.com> wrote: > i have _no_ idea what the differences are between sha1 and > sha1-hard,
SHA1-hard is a modified SHA1 algorithm that is resistant to the SHAttered attack (https://shattered.io/) against SHA1 that came out about a year ago. SHA1-hard generates the same hashes as SHA1, except in the extremely rare cases where the hash is vulnerable to SHAttered. SHA1-hash works by detecting cases where the hash seems to be exploiting weaknesses in the SHA1 compression function and then it makes the hash "safe" by increasing the number of rounds in those rare cases. I converted from using SHA1 to SHA1-hard within about a day of SHAttered being announced. Git also has converted, but it took them months. I also added SHA3 support at the same time. Git is still SHA1-only, the last time I checked. The SHA1-hard code was stolen from https://github.com/cr-marcstevens/sha1collisiondetection. The only changes I made were to clean it up a little and convert it into a single-file implementation so that it was easier to import into the Fossil source tree. -- D. Richard Hipp d...@sqlite.org _______________________________________________ fossil-users mailing list fossil-users@lists.fossil-scm.org http://lists.fossil-scm.org:8080/cgi-bin/mailman/listinfo/fossil-users
