Update some comments and code to reflect the fact that HMAC() is no longer hostile to NULL key data.

Update some comments and code to reflect the fact that HMAC() is no longer hostile to NULL key data.

BUG=395826
Committed: https://crrev.com/b8b8deaa000eb91c7ee394d8cac563b95f3c9643
Cr-Commit-Position: refs/heads/master@{#319178}

[eroman, 2015-03-04 03:28:08]

eroman@chromium.org changed reviewers:
+ davidben@chromium.org

[davidben, 2015-03-04 19:41:00]

https://codereview.chromium.org/975273002/diff/1/content/child/webcrypto/open...
File content/child/webcrypto/openssl/hmac_openssl.cc (right):

https://codereview.chromium.org/975273002/diff/1/content/child/webcrypto/open...
content/child/webcrypto/openssl/hmac_openssl.cc:43: const void* const
raw_key_voidp = raw_key.empty() ? NULL : &raw_key[0];
vector_as_array?

https://codereview.chromium.org/975273002/diff/1/crypto/hmac_openssl.cc
File crypto/hmac_openssl.cc (right):

https://codereview.chromium.org/975273002/diff/1/crypto/hmac_openssl.cc#newco...
crypto/hmac_openssl.cc:34: if (key_length == 0) {
Hrm. This seems to conflict with the documentation. Given we have passing tests
for it, I suspect this comment is just a lie.

https://code.google.com/p/chromium/codesearch#chromium/src/crypto/hmac.h&q=HM...

https://codereview.chromium.org/975273002/diff/1/crypto/hmac_openssl.cc#newco...
crypto/hmac_openssl.cc:36: // HMAC pads keys with zeros, so this key is
equivalent.
Hrm. This seems to only be relevant for the DCHECK. What if we instead defer
initializing plat_ until HMAC::Init? Then we can DCHECK on plat_ existing
without extra state.

[eroman, 2015-03-04 20:50:00]

All great comments, done!

[davidben, 2015-03-05 00:31:29]

lgtm

https://codereview.chromium.org/975273002/diff/20001/crypto/hmac_openssl.cc
File crypto/hmac_openssl.cc (right):

https://codereview.chromium.org/975273002/diff/20001/crypto/hmac_openssl.cc#n...
crypto/hmac_openssl.cc:40: STLClearObject(&plat_->key);
(While you're here, I'm not sure line 40 does anything useful. Line 39 may be
less pointless, if the compile isn't clever enough to optimize it away. *shrug*)

[eroman, 2015-03-05 00:41:11]

https://codereview.chromium.org/975273002/diff/20001/crypto/hmac_openssl.cc
File crypto/hmac_openssl.cc (right):

https://codereview.chromium.org/975273002/diff/20001/crypto/hmac_openssl.cc#n...
crypto/hmac_openssl.cc:40: STLClearObject(&plat_->key);
On 2015/03/05 00:31:29, David Benjamin (slow this week wrote:
> (While you're here, I'm not sure line 40 does anything useful. Line 39 may be
> less pointless, if the compile isn't clever enough to optimize it away.
*shrug*)

Yeah I agree doesn't seem useful. I will propose that separately though to keep
this CL strictly a refactor.

[eroman, 2015-03-05 00:41:52]

The CQ bit was checked by eroman@chromium.org

[commit-bot: I haz the power, 2015-03-05 00:42:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/975273002/20001

[commit-bot: I haz the power, 2015-03-05 00:46:31]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-05 00:47:14]

Patchset 2 (id:??) landed as
https://crrev.com/b8b8deaa000eb91c7ee394d8cac563b95f3c9643
Cr-Commit-Position: refs/heads/master@{#319178}