please add a crypto library (md5, sha1)

[DartBot]

This issue was originally filed by [email protected]

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Please add a crypto library that allows computing hashes and encrypting / decrypting data.

The specific algorithm I want is to compute md5 hashses, but you might as well provide a general library.

Two models to look at for inspiration:

go's crypto package:

http://golang.org/pkg/crypto/

node.js's crypto library:

http://nodejs.org/docs/v0.5.10/api/crypto.html

[floitschG]

Added Area-Library, Triaged labels.

[lexprfuncall]

A pure JS implementation of MD5 can be found in the Google Closure Library.

http://closure-library.googlecode.com/svn/docs/namespace_goog_crypt.html

[DartBot]

This comment was originally written by [email protected]

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Thanks for the tip -- I ported the MD5 implementation from Google's Closure Library to Dart and it works great.

[DartBot]

This comment was originally written by [email protected]

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I've published my port of the Google closure library crypto code here:

http://code.google.com/p/dart-crypto-lib/

[sethladd]

Hi Mads,

You might want to claim ownership of this and update it.

Here's an recent commit: http://code.google.com/p/dart/source/detail?r=7145

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cc @madsager.

[madsager]

Support for sha1, sha256 and HMAC has been added to lib/crypto/crypto.dart. Unfortunately, the library only works on the VM at this point because of issues with bit operations when translating to JavaScript. Those issues are tracked in issue #2725.

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Set owner to @madsager.
Added Started label.

[DartBot]

This comment was originally written by [email protected]

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Is MD5 going to be added to the crypto lib, or is that going to be punted to 3rd-party?

[sethladd]

Marked this as being blocked by #2725.

[madsager]

We should probably add MD5 as well. Out of curiosity, what is your use case for MD5?

[DartBot]

This comment was originally written by [email protected]

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I don't have a good use case for MD5 at the moment.

This feature request was motivated to support a toy BitTorrent client I was writing to compare Dart server performance with a toy "Go" BitTorrent client. (See https://github.com/jackpal/Taipei-Torrent for the toy Go BitTorrent client.)

(I'm not a user of BitTorrent, this is just a fun benchmark for multi-threaded network I/O. I download Ubuntu ISOs as the benchmark test.)

MD5 and SHA1 are both used in the BitTorrent protocol, but it turns out that the MD5 use is optional, and in fact rarely used in practice by torrent clients. It's used for file integrity checking.

http://wiki.theory.org/BitTorrentSpecification

[DartBot]

This comment was originally written by [email protected]

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My use case for MD5 is http://code.google.com/p/oplop/ where I use it to help generate passwords as a masking agent.

[DartBot]

This comment was originally written by [email protected]

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Why not use SHA-1 instead?

[DartBot]

This comment was originally written by [email protected]

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Assuming the question "Why not use SHA-1 instead" was meant for me, the main answer is years-old compatibility. I began developing Oplop way back when all I had was a Nokia S60 phone when they supported Python for app development but only had MD5 as a hash algorithm (I assume because of performance consideration).

If you're asking about it from a security perspective, it's because the hashing algorithm is being used more for consistent randomness than for generating than cryptographic needs. That means MD5's inherent collisions weaknesses is not an issue (much like using MD5 as a cheap checksum instead of as a cryptographically-sound HMAC).

[sethladd]

friendly ping. Crypto is now in. If crypto can be compiled by JavaScript, I think we can close this out.

[madsager]

md5, sha1, sha256 and HMAC has been landed and works compiled to JavaScript as well.

Closing this out for now. Please open more specific bug reports about APIs you would like.

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Added Fixed label.