Add a CreatePSS method to SignatureCreator to permit the generation of PSS signatures.

crypto/signature_creator.h

Index: crypto/signature_creator.h
diff --git a/crypto/signature_creator.h b/crypto/signature_creator.h
index ab9d2c1a21b58cf9e7205668f517c03377c8456a..9fb47b64b6917a344277f41f7bfe4074cc45cf2c 100644
--- a/crypto/signature_creator.h
+++ b/crypto/signature_creator.h
@@ -40,6 +40,11 @@ class CRYPTO_EXPORT SignatureCreator {
   // specified.
   static SignatureCreator* Create(RSAPrivateKey* key, HashAlgorithm hash_alg);
 
+  // Create an instance. The caller must ensure that the provided PrivateKey
+  // instance outlives the created SignatureCreator. Uses the HashAlgorithm
+  // specified. The generated signature will be in the RSA-PSS format.
+  static SignatureCreator* CreatePSS(RSAPrivateKey* key,
+                                     HashAlgorithm hash_alg);
 
   // Signs the precomputed |hash_alg| digest |data| using private |key| as
   // specified in PKCS #1 v1.5.

[Ryan Sleevi, 2015/08/25 20:01:38]

This of course would be inconsistent with your proposed change :)

@@ -56,6 +61,10 @@ class CRYPTO_EXPORT SignatureCreator {
   bool Final(std::vector<uint8>* signature);
 
  private:
+  static SignatureCreator* CreateImpl(RSAPrivateKey* key,

[Ryan Sleevi, 2015/08/25 20:01:38]

This doesn't actually need to be static, does it?

+                                      HashAlgorithm hash_alg,
+                                      bool use_pss);
+
   // Private constructor. Use the Create() method instead.
   SignatureCreator();