CryptoAlgorithmRSASSA_PKCS1_v1_5::platformVerify contains seemingly accidental unreachable code

[Joseph Pecoraro]

Compiling CryptoAlgorithmRSASSA_PKCS1_v1_5Mac.cpp with -Wunreachable-code catches:
Source/WebCore/crypto/mac/CryptoAlgorithmRSASSA_PKCS1_v1_5Mac.cpp:94:24: error: will never be executed [-Werror,-Wunreachable-code]

It looks like a legit warning:

    void CryptoAlgorithmRSASSA_PKCS1_v1_5::platformVerify(const CryptoAlgorithmRsaSsaParams& parameters, const CryptoKeyRSA& key, const CryptoOperationData& signature, const CryptoOperationData& data, BoolCallback callback, VoidCallback failureCallback, ExceptionCode& ec)
    {
        ...

        CCCryptorStatus status = CCRSACryptorVerify(key.platformKey(), ccPKCS1Padding, digestData.data(), digestData.size(), digestAlgorithm, 0, signature.first, signature.second);
        if (!status)
            callback(true);
        else if (status == kCCNotVerified || kCCDecodeError) // <rdar://problem/15464982> CCRSACryptorVerify returns kCCDecodeError instead of kCCNotVerified sometimes
            callback(false);
        else
            failureCallback();
    }

---

The "|| kCCDecodeError" part looks suspicious. Perhaps that should be comparing with status, otherwise it looks like it will always be true, and the "else failureCallback()" will never be reached.

[Alexey Proskuryakov]

Created attachment 224943 [details]
proposed fix

[Joseph Pecoraro]

Comment on attachment 224943 [details]
proposed fix

r=me!

Should we write a test?

[Alexey Proskuryakov]

Comment on attachment 224943 [details]
proposed fix

> Should we write a test?

I don't think that there is any way to get to the failureCallback() branch in practice.

[WebKit Commit Bot]

Comment on attachment 224943 [details]
proposed fix

Clearing flags on attachment: 224943

Committed r164528: <http://trac.webkit.org/changeset/164528>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.