Make the Nigori user salt key 80-bits to be FIPS compliant.

Make the Nigori user salt key 128-bits to be FIPS compliant.

BUG=none
TEST=NigoriTest.*

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=45816

[albertb, 2010-04-26 17:37:21]

Ben has updated the Nigori spec to require 80-bits for the user salt key, so I'm
updating the Nigori code and reverting the change I did on Mac.

[wtc, 2010-04-26 18:19:10]

LGTM.

http://codereview.chromium.org/1697010/diff/1/2
File base/crypto/symmetric_key_mac.cc (right):

http://codereview.chromium.org/1697010/diff/1/2#newcode27
base/crypto/symmetric_key_mac.cc:27: CHECK(key_size_in_bits >= 80 &&
(key_size_in_bits % 8) == 0)
I suggest that you add a comment to explain what 80 means
(SHA-1 output size / 2), and that this requirement comes
from FIPS 198 Section 3.

http://codereview.chromium.org/1697010/diff/1/3
File chrome/browser/sync/util/nigori.h (right):

http://codereview.chromium.org/1697010/diff/1/3#newcode53
chrome/browser/sync/util/nigori.h:53: static const size_t kSaltKeySizeInBits =
80;
In the email thread, Ben said he's upped this to 16 bytes.
Then this constant should be 128 as opposed to 80.  Could you
please doublecheck?

[albertb, 2010-04-27 18:29:15]

http://codereview.chromium.org/1697010/diff/1/3
File chrome/browser/sync/util/nigori.h (right):

http://codereview.chromium.org/1697010/diff/1/3#newcode53
chrome/browser/sync/util/nigori.h:53: static const size_t kSaltKeySizeInBits =
80;
On 2010/04/26 18:19:11, wtc wrote:
> In the email thread, Ben said he's upped this to 16 bytes.
> Then this constant should be 128 as opposed to 80.  Could you
> please doublecheck?

Ben has updated the doc to specify 16 bytes.

[wtc, 2010-04-27 18:38:06]

LGTM.

http://codereview.chromium.org/1697010/diff/7001/8001
File base/crypto/symmetric_key_mac.cc (right):

http://codereview.chromium.org/1697010/diff/7001/8001#newcode26
base/crypto/symmetric_key_mac.cc:26: // FIPS 198 Section 3 requires the a SHA-1
derived key to be at least
Nit: SHA-1 derived key => HMAC-SHA-1 key