- Add lib/crypto.

- Add lib/crypto.
- Add a static SHA1 implementation.
Committed: https://code.google.com/p/dart/source/detail?r=6875

[Ivan Posva, 2012-04-24 09:23:53]

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart
File crypto/crypto.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:5: // Helpers used implementing the different crypto
algorithms.
We might want to move these helpers into their own file if we feel like it and
only have the public interfaces in here once they have been defined.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:58: List<int> _wordsToBytes(List<int> input) {
This should change to take an output target, as well as offsets and lengths for
both input and output.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart
File crypto/sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newco...
crypto/sha1.dart:10: len = input_len - offset;
It might be bad form to overwrite the input, what do you think?

[Mads Ager (google), 2012-04-24 09:57:46]

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart
File crypto/crypto.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:1: #library("crypto");
Copyright.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:5: // Helpers used implementing the different crypto
algorithms.
On 2012/04/24 09:23:53, Ivan Posva wrote:
> We might want to move these helpers into their own file if we feel like it and
> only have the public interfaces in here once they have been defined.

Yes, I can do that in the next round.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:19: return ((val << mod_shift) & _MASK_32) | ((val &
_MASK_32) >> (32 - mod_shift));
Long line.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart
File crypto/sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newcode1
crypto/sha1.dart:1: class SHA1 {
Copyright.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newco...
crypto/sha1.dart:51: ((j < 20) ? (((b & c) | (~b & d)) + 0x5A827999) :
I would prefer the more readable version with if statements.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/test_sha1.dart
File crypto/test_sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/test_sha1.dart#...
crypto/test_sha1.dart:1: #import("crypto.dart");
Copyright notice.

Also, we need to put this in a test directory and make sure that it is run as an
automated test.

[Søren Gjesse, 2012-04-24 10:30:56]

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart
File crypto/sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newcode1
crypto/sha1.dart:1: class SHA1 {
Shouldn't we define an interface common for all hash algorithms?

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newco...
crypto/sha1.dart:10: len = input_len - offset;
On 2012/04/24 09:23:53, Ivan Posva wrote:
> It might be bad form to overwrite the input, what do you think?

I have no problem with that.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newco...
crypto/sha1.dart:33: m[(((l + 64) >> 9) << 4) + 15] = l;
If length is larger than (2^32 - 1) it should be split into two words.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/test_sha1.dart
File crypto/test_sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/test_sha1.dart#...
crypto/test_sha1.dart:1: #import("crypto.dart");
Shouldn't this test be in directory tests/utils/src and be named Sha1Test.dart?

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/test_sha1.dart#...
crypto/test_sha1.dart:6: arr[i] = i;
arr[i] = i & 0xFF

to keep the input valid.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/test_sha1.dart#...
crypto/test_sha1.dart:19: void testStatic() {
Having the hash values in an array and then use a loop would cut the length of
this file in half.

[Ivan Posva, 2012-04-24 13:02:35]

The testing code needs quite a bit more infrastructure, so I will roll this into
a separate change.

-Ivan

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart
File crypto/crypto.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:1: #library("crypto");
On 2012/04/24 09:57:46, Mads Ager wrote:
> Copyright.

Done.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/crypto.dart#new...
crypto/crypto.dart:19: return ((val << mod_shift) & _MASK_32) | ((val &
_MASK_32) >> (32 - mod_shift));
On 2012/04/24 09:57:46, Mads Ager wrote:
> Long line.

Done.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart
File crypto/sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newcode1
crypto/sha1.dart:1: class SHA1 {
On 2012/04/24 10:30:56, Søren Gjesse wrote:
> Shouldn't we define an interface common for all hash algorithms?

Since this has only a static method an implementing an interface is unnecessary.
Mads has volunteered to define the logical extension of this to implement a
shared interface between different hashing algorithms which can be used with
chunked data and or streaming.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newcode1
crypto/sha1.dart:1: class SHA1 {
On 2012/04/24 09:57:46, Mads Ager wrote:
> Copyright.

Done.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newco...
crypto/sha1.dart:33: m[(((l + 64) >> 9) << 4) + 15] = l;
On 2012/04/24 10:30:56, Søren Gjesse wrote:
> If length is larger than (2^32 - 1) it should be split into two words.

Added a TODO to deal with this once we support arrays large enough to run into
this issue.

https://chromiumcodereview.appspot.com/10196011/diff/1/crypto/sha1.dart#newco...
crypto/sha1.dart:51: ((j < 20) ? (((b & c) | (~b & d)) + 0x5A827999) :
On 2012/04/24 09:57:46, Mads Ager wrote:
> I would prefer the more readable version with if statements.

Done.

[Søren Gjesse, 2012-04-24 13:14:11]

lgtm

https://chromiumcodereview.appspot.com/10196011/diff/6/crypto/sha1.dart
File crypto/sha1.dart (right):

https://chromiumcodereview.appspot.com/10196011/diff/6/crypto/sha1.dart#newco...
crypto/sha1.dart:36: // TODO(iposva): Deal with lengths longer than 32-bits once
arrays can
When we change to an interface where you can call update with message chunks
this is no longer bounded by the max list length in the VM.

Btw. right now

  new List<int>(65536 * 65536 ~/ 8);

seg-faults the VM.

[Mads Ager (google), 2012-04-24 13:16:41]

LGTM, I'll take over from here. I'll put in sha256 and use a common interface.
I'll add tests as well.