[webcrypto] Refactor RSA-SSA signing.

This extracts the signing/verification functions, so the subsequent RSA-PSS changelist is easier to follow.

BUG=399090

Review URL: https://codereview.chromium.org/662533002

Cr-Commit-Position: refs/heads/master@{#300194}

4 files changed, 148 insertions, 76 deletions

diff --git a/content/child/webcrypto/openssl/rsa_sign_openssl.cc b/content/child/webcrypto/openssl/rsa_sign_openssl.cc
new file mode 100644
index 0000000..b77aed1
--- /dev/null
+++ b/content/child/webcrypto/openssl/rsa_sign_openssl.cc
@@ -0,0 +1,105 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/child/webcrypto/crypto_data.h"
+#include "content/child/webcrypto/openssl/key_openssl.h"
+#include "content/child/webcrypto/openssl/rsa_key_openssl.h"
+#include "content/child/webcrypto/openssl/rsa_sign_openssl.h"
+#include "content/child/webcrypto/openssl/util_openssl.h"
+#include "content/child/webcrypto/status.h"
+#include "crypto/openssl_util.h"
+#include "crypto/scoped_openssl_types.h"
+#include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
+
+namespace content {
+
+namespace webcrypto {
+
+namespace {
+
+// Extracts the OpenSSL key and digest from a WebCrypto key. The returned
+// pointers will remain valid as long as |key| is alive.
+Status GetPKeyAndDigest(const blink::WebCryptoKey& key,
+                        EVP_PKEY** pkey,
+                        const EVP_MD** digest) {
+  *pkey = AsymKeyOpenSsl::Cast(key)->key();
+
+  *digest = GetDigest(key.algorithm().rsaHashedParams()->hash().id());
+  if (!*digest)
+    return Status::ErrorUnsupported();
+
+  return Status::Success();
+}
+
+}  // namespace
+
+Status RsaSign(const blink::WebCryptoKey& key,
+               const CryptoData& data,
+               std::vector<uint8_t>* buffer) {
+  if (key.type() != blink::WebCryptoKeyTypePrivate)
+    return Status::ErrorUnexpectedKeyType();
+
+  crypto::OpenSSLErrStackTracer err_tracer(FROM_HERE);
+  crypto::ScopedEVP_MD_CTX ctx(EVP_MD_CTX_create());
+
+  EVP_PKEY* private_key = NULL;
+  const EVP_MD* digest = NULL;
+  Status status = GetPKeyAndDigest(key, &private_key, &digest);
+  if (status.IsError())
+    return status;
+
+  // NOTE: A call to EVP_DigestSignFinal() with a NULL second parameter
+  // returns a maximum allocation size, while the call without a NULL returns
+  // the real one, which may be smaller.
+  size_t sig_len = 0;
+  if (!ctx.get() ||
+      !EVP_DigestSignInit(ctx.get(), NULL, digest, NULL, private_key) ||
+      !EVP_DigestSignUpdate(ctx.get(), data.bytes(), data.byte_length()) ||
+      !EVP_DigestSignFinal(ctx.get(), NULL, &sig_len)) {
+    return Status::OperationError();
+  }
+
+  buffer->resize(sig_len);
+  if (!EVP_DigestSignFinal(ctx.get(), &buffer->front(), &sig_len))
+    return Status::OperationError();
+
+  buffer->resize(sig_len);
+  return Status::Success();
+}
+
+Status RsaVerify(const blink::WebCryptoKey& key,
+                 const CryptoData& signature,
+                 const CryptoData& data,
+                 bool* signature_match) {
+  if (key.type() != blink::WebCryptoKeyTypePublic)
+    return Status::ErrorUnexpectedKeyType();
+
+  crypto::OpenSSLErrStackTracer err_tracer(FROM_HERE);
+  crypto::ScopedEVP_MD_CTX ctx(EVP_MD_CTX_create());
+
+  EVP_PKEY* public_key = NULL;
+  const EVP_MD* digest = NULL;
+  Status status = GetPKeyAndDigest(key, &public_key, &digest);
+  if (status.IsError())
+    return status;
+
+  if (!EVP_DigestVerifyInit(ctx.get(), NULL, digest, NULL, public_key))
+    return Status::OperationError();
+
+  if (!EVP_DigestVerifyUpdate(ctx.get(), data.bytes(), data.byte_length()))
+    return Status::OperationError();
+
+  // Note that the return value can be:
+  //   1 --> Success
+  //   0 --> Verification failed
+  //  <0 --> Operation error
+  int rv = EVP_DigestVerifyFinal(
+      ctx.get(), signature.bytes(), signature.byte_length());
+  *signature_match = rv == 1;
+  return rv >= 0 ? Status::Success() : Status::OperationError();
+}
+
+}  // namespace webcrypto
+
+}  // namespace content
diff --git a/content/child/webcrypto/openssl/rsa_sign_openssl.h b/content/child/webcrypto/openssl/rsa_sign_openssl.h
new file mode 100644
index 0000000..d180ab4
--- /dev/null
+++ b/content/child/webcrypto/openssl/rsa_sign_openssl.h
@@ -0,0 +1,38 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_CHILD_WEBCRYPTO_OPENSSL_RSA_SIGN_OPENSSL_H_
+#define CONTENT_CHILD_WEBCRYPTO_OPENSSL_RSA_SIGN_OPENSSL_H_
+
+#include <stdint.h>
+
+#include <vector>
+
+namespace blink {
+class WebCryptoKey;
+}
+
+namespace content {
+
+namespace webcrypto {
+
+class CryptoData;
+class Status;
+
+// Helper functions for doing RSA-SSA signing and verification.
+
+Status RsaSign(const blink::WebCryptoKey& key,
+               const CryptoData& data,
+               std::vector<uint8_t>* buffer);
+
+Status RsaVerify(const blink::WebCryptoKey& key,
+                 const CryptoData& signature,
+                 const CryptoData& data,
+                 bool* signature_match);
+
+}  // namespace webcrypto
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_WEBCRYPTO_OPENSSL_RSA_SIGN_OPENSSL_H_
diff --git a/content/child/webcrypto/openssl/rsa_ssa_openssl.cc b/content/child/webcrypto/openssl/rsa_ssa_openssl.cc
index fc574cd..be974cc 100644
--- a/content/child/webcrypto/openssl/rsa_ssa_openssl.cc
+++ b/content/child/webcrypto/openssl/rsa_ssa_openssl.cc
@@ -2,14 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "content/child/webcrypto/crypto_data.h"
-#include "content/child/webcrypto/openssl/key_openssl.h"
 #include "content/child/webcrypto/openssl/rsa_key_openssl.h"
-#include "content/child/webcrypto/openssl/util_openssl.h"
+#include "content/child/webcrypto/openssl/rsa_sign_openssl.h"
 #include "content/child/webcrypto/status.h"
-#include "crypto/openssl_util.h"
-#include "crypto/scoped_openssl_types.h"
-#include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
 
 namespace content {
 
@@ -17,20 +12,6 @@ namespace webcrypto {
 
 namespace {
 
-// Extracts the OpenSSL key and digest from a WebCrypto key. The returned
-// pointers will remain valid as long as |key| is alive.
-Status GetPKeyAndDigest(const blink::WebCryptoKey& key,
-                        EVP_PKEY** pkey,
-                        const EVP_MD** digest) {
-  *pkey = AsymKeyOpenSsl::Cast(key)->key();
-
-  *digest = GetDigest(key.algorithm().rsaHashedParams()->hash().id());
-  if (!*digest)
-    return Status::ErrorUnsupported();
-
-  return Status::Success();
-}
-
 class RsaSsaImplementation : public RsaHashedAlgorithm {
  public:
   RsaSsaImplementation()
@@ -57,35 +38,7 @@ class RsaSsaImplementation : public RsaHashedAlgorithm {
                       const blink::WebCryptoKey& key,
                       const CryptoData& data,
                       std::vector<uint8_t>* buffer) const override {
-    if (key.type() != blink::WebCryptoKeyTypePrivate)
-      return Status::ErrorUnexpectedKeyType();
-
-    crypto::OpenSSLErrStackTracer err_tracer(FROM_HERE);
-    crypto::ScopedEVP_MD_CTX ctx(EVP_MD_CTX_create());
-
-    EVP_PKEY* private_key = NULL;
-    const EVP_MD* digest = NULL;
-    Status status = GetPKeyAndDigest(key, &private_key, &digest);
-    if (status.IsError())
-      return status;
-
-    // NOTE: A call to EVP_DigestSignFinal() with a NULL second parameter
-    // returns a maximum allocation size, while the call without a NULL returns
-    // the real one, which may be smaller.
-    size_t sig_len = 0;
-    if (!ctx.get() ||
-        !EVP_DigestSignInit(ctx.get(), NULL, digest, NULL, private_key) ||
-        !EVP_DigestSignUpdate(ctx.get(), data.bytes(), data.byte_length()) ||
-        !EVP_DigestSignFinal(ctx.get(), NULL, &sig_len)) {
-      return Status::OperationError();
-    }
-
-    buffer->resize(sig_len);
-    if (!EVP_DigestSignFinal(ctx.get(), &buffer->front(), &sig_len))
-      return Status::OperationError();
-
-    buffer->resize(sig_len);
-    return Status::Success();
+    return RsaSign(key, data, buffer);
   }
 
   virtual Status Verify(const blink::WebCryptoAlgorithm& algorithm,
@@ -93,33 +46,7 @@ class RsaSsaImplementation : public RsaHashedAlgorithm {
                         const CryptoData& signature,
                         const CryptoData& data,
                         bool* signature_match) const override {
-    if (key.type() != blink::WebCryptoKeyTypePublic)
-      return Status::ErrorUnexpectedKeyType();
-
-    crypto::OpenSSLErrStackTracer err_tracer(FROM_HERE);
-    crypto::ScopedEVP_MD_CTX ctx(EVP_MD_CTX_create());
-
-    EVP_PKEY* public_key = NULL;
-    const EVP_MD* digest = NULL;
-    Status status = GetPKeyAndDigest(key, &public_key, &digest);
-    if (status.IsError())
-      return status;
-
-    if (!EVP_DigestVerifyInit(ctx.get(), NULL, digest, NULL, public_key))
-      return Status::OperationError();
-
-    if (!EVP_DigestVerifyUpdate(ctx.get(), data.bytes(), data.byte_length())) {
-      return Status::OperationError();
-    }
-
-    // Note that the return value can be:
-    //   1 --> Success
-    //   0 --> Verification failed
-    //  <0 --> Operation error
-    int rv = EVP_DigestVerifyFinal(
-        ctx.get(), signature.bytes(), signature.byte_length());
-    *signature_match = rv == 1;
-    return rv >= 0 ? Status::Success() : Status::OperationError();
+    return RsaVerify(key, signature, data, signature_match);
   }
 };
 
diff --git a/content/content_child.gypi b/content/content_child.gypi
index e2d0610..f99b61e 100644
--- a/content/content_child.gypi
+++ b/content/content_child.gypi
@@ -284,6 +284,8 @@
       'child/webcrypto/openssl/rsa_key_openssl.cc',
       'child/webcrypto/openssl/rsa_key_openssl.h',
       'child/webcrypto/openssl/rsa_oaep_openssl.cc',
+      'child/webcrypto/openssl/rsa_sign_openssl.cc',
+      'child/webcrypto/openssl/rsa_sign_openssl.h',
       'child/webcrypto/openssl/rsa_ssa_openssl.cc',
       'child/webcrypto/openssl/sha_openssl.cc',
       'child/webcrypto/openssl/sym_key_openssl.cc',