Tool to compute SHA256 Tree Hash

Question

I've started using AWS Glacier, and noticed that it hashes the files using an algorithm called SHA-256 Tree Hash.

To my surprise, this algorithm is different from SHA-256, so I can't use the tools I'm used to, to compare hashes and verify file integrity.

Do you know a Windows tool, if possible integrated in the context menu, to compute the SHA-256 Tree Hash of a file?

I'd also accept a Linux command-line tool, as a second choice :-)

Solution

After a bit more research, it looks like the concept of SHA-256 Tree Hash is something specific to Amazon Glacier, hence the difficulty to find any tool that supports it.

However, the Glacier documentation provides sample code to compute the hash, in Java and C#. Both compile into a command-line tool that computes the hash of the file given as an argument.

I just copied and pasted the C# code in the free Visual C# 2010 Express, compiled it, and I now have the command line tool I was looking for!

Comments

[DerfK]

stackoverflow.com/questions/12058011/… explains what the SHA-256 Tree Hash is, but I don't know of any ready-made programs to do it.

[Magellan]

Questions that are effectively requests for product recommendations are off-topic for ServerFault. Please see: blog.stackoverflow.com/2010/11/qa-is-hard-lets-go-shopping

[BenMorel]

@Adrian Thanks. But I've read that link, and can't see how it relates to my question. I'm not asking for the best tool to do the job, but instead if such a tool exists, and where to find it. I've found the answer to my question anyway, so no worries.

[Magellan]

The 'if exists and where to find it' part is what makes it a 'Shopping' question. If you have any questions about how that works, I definitely encourage you to visit Meta.Serverfault and inquire there.

[Philip]

If a question distills to "I'm looking for $PRODUCT with $FEATURES" then it's a shopping Question. This one is "I'm looking for a utility with SHA-256 Tree Hash capabilities."

[BenMorel]

Say I got your point, how/where should I have asked this question, then?

[Dan Ciborowski - MSFT]

Years later... I am proposing a place for this type of question, and referencing this question as a good question without a home... area51.stackexchange.com/proposals/82757/…

[obaqueiro]

Just for future reference. There's also a Ruby gem that can be installed and used to calculate the SHA2-256 treehash sum: github.com/erichmenge/treehash

[David Ehrmann]

Isn't the AWS tree hash just a Merkle tree with SHA-256?

[Guilherme Garnier]

I've created a Docker image to run this sample code: hub.docker.com/r/ggarnier/glacier-sha256-tree-hash

[user1587520]

Here a pure bash implementation using openssl: github.com/tkb-/glaciertools

[Jason]

This question is a duplicate of: serverfault.com/questions/643222/… Follow the above link for more detailed and up-to-date answers

[BenMorel]

@Jason The linked question is actually a duplicate of this one, coming 2 years later. It's actually funny that it has not been closed as well as a "product recommendation" as they like to call it.