Differential D543
gpg: Use SHA-256 as default s2k-digest-algo Authored by onovy on Nov 26 2021, 8:26 AM.
Details
The U.S. National Institute of Standards and Technology has banned the use of SHA-1 by U.S. federal agencies since 2010. Better solution would be Argon 2id, but GPG doesn't support it (now?).
hash should be 8 (SHA-256) instead of 2 (SHA-1).
Diff Detail
Event TimelineComment Actions Sorry, we won't do that. Actually SHA-1 is still allowed when used in a KDF mechanism like S2K. OpenPGp is about Public Key cryptography and for that it is important to keep the keys safe. Protection the private key with a passaord is a failstop scheme which gives time to revoke the actual key and handle the compromise. When suing symmtric encryption (gpg -c) ist is strongly sutested to use a password with at least 128 bit entropy (e.g. by using our magic wand button). The S2K iteration is actually not needed in such a case. Comment Actions Right, but SHA-256 have higher time consuption, which is always good in password stretching. Current notebooks hit maximum value for s2k_count: which lowers security of stretched password, because time cost is limited. |