s3sha256sum
Calculate SHA256 checksums of objects on Amazon S3.
GPL-3.0 License
This release implements https://github.com/minio/sha256-simd for hardware accelerated hashing.
Published by stefansundin about 2 years ago
This is the first binary release of s3sha256sum.
Since s3sha256sum's introduction, the most exciting new feature in S3 is the Additional Checksum Algorithms feature released in February 2022. It is now possible to verify that an object on S3 is identical to a local file, without the need to download the object from S3. If this capability had existed before then I might not have made s3sha256sum in the first place. However, I still see value in embedding the plain checksum in the object metadata, especially for multi-part uploads, in addition to using the new checksum algorithm feature.
As is often the case, AWS has not published any tooling of their own that will help you perform verification using the new checksum algorithm feature, so I had to make my own: s3verify. Consider using it instead of s3sha256sum. Keep in mind that the objects have to be uploaded using this feature for the verification to be possible.
s3sha256sum will soon adopt zflag to make s3sha256sum's handling of command line arguments more similar to the aws cli. I wanted to make a binary release with the current argument handling before this change happens. Please use v0.1.0 if you need compatibility with how arguments were processed in the pre-release version.