[webcrypto] Add JWK import/export of RSA private keys (NSS).

content/child/webcrypto/shared_crypto.h

Index: content/child/webcrypto/shared_crypto.h
diff --git a/content/child/webcrypto/shared_crypto.h b/content/child/webcrypto/shared_crypto.h
index 47c623b64db1be4ddde8c0374cc8e149a90f8e8e..57627d60b0dad359a47ce5a620517ab5d95a9fd2 100644
--- a/content/child/webcrypto/shared_crypto.h
+++ b/content/child/webcrypto/shared_crypto.h
@@ -160,6 +160,20 @@ CONTENT_EXPORT bool DeserializeKeyForClone(
     const CryptoData& key_data,
     blink::WebCryptoKey* key);
 
+namespace platform {
+class SymKey;
+class PublicKey;
+class PrivateKey;
+}
+
+Status ToPlatformSymKey(const blink::WebCryptoKey& key, platform::SymKey** out);
+
+Status ToPlatformPublicKey(const blink::WebCryptoKey& key,
+                           platform::PublicKey** out);
+
+Status ToPlatformPrivateKey(const blink::WebCryptoKey& key,
+                            platform::PrivateKey** out);

[Ryan Sleevi, 2014/05/19 00:10:34]

Feels like a layering violation. I'm not sure why you introduced these?

[eroman, 2014/05/19 18:51:09]

I exposed these for re-use in jwk.cc.

jwk.cc was already using ToPlatformPublicKey() via duplication. This CL now
required ToPlatformPrivateKey() as well. Rather than duplicate that as well, I
decided to expose them.

I agree shared_crypto.h is not the best place for these, however the other files
are also unsuited.

platform_crypto.h would be a reasonable place to expose the declaration, however
the issue is where to put the definition (there is no platform_crypto.cc, only
platform_crypto_nss.cc and platform_crypto_openssl.cc).

Suggestions? I could declare in platform_crypto.h and then define in
shared_crypto.cc but that feels strange too.

+
 }  // namespace webcrypto
 
 }  // namespace content