crypto: change ECSignatureCreator defaults to match SPDY.

crypto/ec_signature_creator_nss.cc

Index: crypto/ec_signature_creator_nss.cc
diff --git a/crypto/ec_signature_creator_nss.cc b/crypto/ec_signature_creator_nss.cc
index a85b1e94fecf20299494fcffdc95c7894fb375da..40949f0b56a519a1137f6570bb34b12b78e26280 100644
--- a/crypto/ec_signature_creator_nss.cc
+++ b/crypto/ec_signature_creator_nss.cc
@@ -79,7 +79,7 @@ bool ECSignatureCreatorImpl::Sign(const uint8* data,
 
   // Sign the secret data and save it to |result|.
   SECStatus rv =
-      SignData(&result, &secret, key_->key(), HASH_AlgSHA1);
+      SignData(&result, &secret, key_->key(), HASH_AlgSHA256);
   if (rv != SECSuccess) {
     DLOG(ERROR) << "DerSignData: " << PORT_GetError();
     return false;
@@ -91,4 +91,20 @@ bool ECSignatureCreatorImpl::Sign(const uint8* data,
   return true;
 }
 
+bool ECSignatureCreatorImpl::DecodeSignature(const std::vector<uint8>& der_sig,
+                                             std::string* out_raw_sig) {
+  SECItem der_sig_item;
+  der_sig_item.type = siBuffer;
+  der_sig_item.len = der_sig.size();
+  der_sig_item.data = const_cast<uint8*>(der_sig.data());
+
+  static const int kP256ScalarBytes = 32;
+  SECItem* raw_sig = DSAU_DecodeDerSigToLen(&der_sig_item, 2*kP256ScalarBytes);
+  if (!raw_sig)
+    return false;
+  out_raw_sig->assign(reinterpret_cast<char*>(raw_sig->data), raw_sig->len);
+  SECITEM_FreeItem(raw_sig, PR_TRUE /* free SECItem structure itself. */);
+  return true;
+}
+
 }  // namespace crypto