Introduce SignatureCreator.

Introduce SignatureCreator.

[Aaron Boodman, 2009-06-04 22:28:10]

Please ignore the unchanged file and the lack of vcproj update. This is the
result of git shenanigans that I will fix before committing.

[Erik does not do reviews, 2009-06-04 23:23:46]

LGTM

http://codereview.chromium.org/118277/diff/1001/1004
File base/crypto/signature_creator.cc (right):

http://codereview.chromium.org/118277/diff/1001/1004#newcode28
Line 28: if (!CryptDestroyHash(hash_object_)) {
unneeded {}

http://codereview.chromium.org/118277/diff/1001/1004#newcode47
Line 47: &signature_length))
with multi-line conditional, use {} (another one after this)

http://codereview.chromium.org/118277/diff/1001/1006
File base/crypto/signature_creator_unittest.cc (right):

http://codereview.chromium.org/118277/diff/1001/1006#newcode31
Line 31: const uint8 signature_algorithm[] = {
comment explaining what this is and where it's from.
Do we use this same sequence other places?  maybe it should be a constant
somewhere.

[wtc, 2009-06-04 23:29:34]

LGTM.  Good progress!

http://codereview.chromium.org/118277/diff/1001/1002
File base/crypto/rsa_key_pair.h (right):

http://codereview.chromium.org/118277/diff/1001/1002#newcode38
Line 38: HCRYPTPROV provider() { return provider_; }
Each class should be responsible for opening its own provider.
In the future we can add a class that returns a global
provider handle that everyone can use.

http://codereview.chromium.org/118277/diff/1001/1002#newcode39
Line 39: HCRYPTKEY key() { return key_; }
Probably should name this class RSAPrivateKey.

(An RSA private key contains enough info for you to derive
the corresponding public key, so it can also be considered
a key pair.)

http://codereview.chromium.org/118277/diff/1001/1005
File base/crypto/signature_creator.h (right):

http://codereview.chromium.org/118277/diff/1001/1005#newcode22
Line 22: // Signs data using a base cryptographic key pair (as opposed to a
certificate).
The hardcoded use of sha1WithRsaEncryption signature
algorithm should be documented here.

http://codereview.chromium.org/118277/diff/1001/1005#newcode26
Line 26: static SignatureCreator* Create(RSAKeyPair* key);
It's too bad the SignatureCreator interface isn't symmetric
to the SignatureVerifier interface.  They differ in:
1. How an instance is created
2. std::vector<uint8>

http://codereview.chromium.org/118277/diff/1001/1005#newcode44
Line 44: #endif
Should we add DISALLOW_COPY_AND_ASSIGN?