[webcrypto] Add JWK import for HMAC and AES-CBC key.

content/renderer/webcrypto/webcrypto_util.cc

+// Copyright (c) 2013 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 "base/base64.h"
+#include "base/logging.h"
+#include "content/renderer/webcrypto/webcrypto_util.h"

[eroman, 2013/10/28 23:02:00]

This header goes first, and then the rest (the header for the .cc file has
special treatment in the sorting).

[padolph, 2013/10/29 02:25:40]

Done.

+#include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
+
+namespace content {
+
+namespace {
+
+WebKit::WebCryptoAlgorithm CreateAesKeyGenAlgorithm(
+    WebKit::WebCryptoAlgorithmId aes_alg_id,
+    unsigned short length) {
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(
+      aes_alg_id, new WebKit::WebCryptoAesKeyGenParams(length));
+}
+
+WebKit::WebCryptoAlgorithm CreateAlgorithmWithInnerHash(
+    WebKit::WebCryptoAlgorithmId algorithm_id,
+    unsigned short hash_key_length) {
+  WebKit::WebCryptoAlgorithmId hash_id;
+  switch (hash_key_length) {
+    case 160:
+      hash_id = WebKit::WebCryptoAlgorithmIdSha1;
+      break;
+    case 224:
+      hash_id = WebKit::WebCryptoAlgorithmIdSha224;
+      break;
+    case 256:
+      hash_id = WebKit::WebCryptoAlgorithmIdSha256;
+      break;
+    case 384:
+      hash_id = WebKit::WebCryptoAlgorithmIdSha384;
+      break;
+    case 512:
+      hash_id = WebKit::WebCryptoAlgorithmIdSha384;
+      break;
+    default:
+      NOTREACHED();
+      // FIXME WRONG TYPE
+      return CreateAlgorithm(WebKit::WebCryptoAlgorithmIdAesCbc);
+      // return WebKit::WebCryptoAlgorithm::createNull();
+  }
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(
+      algorithm_id, new WebKit::WebCryptoHmacParams(CreateAlgorithm(hash_id)));
+}
+
+}

[eroman, 2013/10/28 23:02:00]

End with a comment "  // namespace" to help matching

[padolph, 2013/10/29 02:25:40]

Done.

+
+// Returns a pointer to the start of |data|, or NULL if it is empty. This is a
+// convenience function for getting the pointer, and should not be used beyond
+// the expected lifetime of |data|.
+const uint8* Start(const std::vector<uint8>& data) {
+  if (data.empty())
+    return NULL;
+  return &data[0];
+}
+
+// TODO(eroman): This works by re-allocating a new buffer. It would be better if
+//               the WebArrayBuffer could just be truncated instead.
+void ShrinkBuffer(WebKit::WebArrayBuffer* buffer, unsigned new_size) {
+  DCHECK_LE(new_size, buffer->byteLength());
+
+  if (new_size == buffer->byteLength())
+    return;
+
+  WebKit::WebArrayBuffer new_buffer =
+      WebKit::WebArrayBuffer::create(new_size, 1);
+  DCHECK(!new_buffer.isNull());
+  memcpy(new_buffer.data(), buffer->data(), new_size);
+  *buffer = new_buffer;
+}
+
+// This function decodes unpadded 'base64url' encoded data, as described in
+// RFC4648 (http://www.ietf.org/rfc/rfc4648.txt) Section 5. To do this, first
+// change the incoming data to 'base64' encoding by applying the appropriate
+// transformation including adding padding if required, and then call a base64
+// decoder.
+// In Web Crypto, this type of encoding is only used inside JWK.
+bool Base64DecodeUrlSafe(const std::string& input, std::string* output) {
+  std::string base64EncodedText(input);
+  std::replace(base64EncodedText.begin(), base64EncodedText.end(), '-', '+');
+  std::replace(base64EncodedText.begin(), base64EncodedText.end(), '_', '/');
+  base64EncodedText.append((4 - base64EncodedText.size() % 4) % 4, '=');
+  return base::Base64Decode(base64EncodedText, output);
+}
+
+// *** Algorithm Factories ***
+
+WebKit::WebCryptoAlgorithm CreateAlgorithm(WebKit::WebCryptoAlgorithmId id) {
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(id, NULL);
+}
+
+// HMAC Operations Algorithm Factories
+
+WebKit::WebCryptoAlgorithm CreateHmacAlgorithmByKeyLen(
+    unsigned short hash_key_length) {
+  return CreateAlgorithmWithInnerHash(WebKit::WebCryptoAlgorithmIdHmac,
+                                      hash_key_length);
+}
+
+WebKit::WebCryptoAlgorithm CreateHmacAlgorithmByHashId(
+    WebKit::WebCryptoAlgorithmId hashId) {
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(
+      WebKit::WebCryptoAlgorithmIdHmac,
+      new WebKit::WebCryptoHmacParams(CreateAlgorithm(hashId)));
+}
+
+// HMAC Key Generation Algorithm Factories
+
+WebKit::WebCryptoAlgorithm CreateHmacKeyGenAlgorithm(
+    WebKit::WebCryptoAlgorithmId hashId,
+    unsigned hash_length) {
+  // hash_length < 0 means unspecified
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(
+      WebKit::WebCryptoAlgorithmIdHmac,
+      new WebKit::WebCryptoHmacKeyParams(
+          CreateAlgorithm(hashId), (hash_length != 0), hash_length));
+}
+
+// RSA Operations Algorithm Factories
+
+WebKit::WebCryptoAlgorithm CreateRsaEsAlgorithm() {
+  return CreateAlgorithm(WebKit::WebCryptoAlgorithmIdRsaEsPkcs1v1_5);
+}
+
+WebKit::WebCryptoAlgorithm CreateRsaSsaAlgorithmByKeyLen(
+    unsigned short hash_key_length) {
+  return CreateAlgorithmWithInnerHash(
+      WebKit::WebCryptoAlgorithmIdRsaSsaPkcs1v1_5, hash_key_length);
+}
+
+WebKit::WebCryptoAlgorithm CreateRsaOaepAlgorithmByKeyLen(
+    unsigned short hash_key_length) {
+  return CreateAlgorithmWithInnerHash(WebKit::WebCryptoAlgorithmIdRsaOaep,
+                                      hash_key_length);
+}
+
+// AES Operations Algorithm Factories
+
+WebKit::WebCryptoAlgorithm CreateAesCbcAlgorithm(const std::vector<uint8>& iv) {
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(
+      WebKit::WebCryptoAlgorithmIdAesCbc,
+      new WebKit::WebCryptoAesCbcParams(Start(iv), iv.size()));
+}
+
+WebKit::WebCryptoAlgorithm CreateAesGcmAlgorithm(
+    const std::vector<uint8>& iv,
+    const std::vector<uint8>& additionalData,
+    unsigned char tagLength) {
+  return WebKit::WebCryptoAlgorithm::adoptParamsAndCreate(
+      WebKit::WebCryptoAlgorithmIdAesCbc,
+      new WebKit::WebCryptoAesGcmParams(Start(iv),
+                                        iv.size(),
+                                        additionalData.size(),
+                                        Start(additionalData),
+                                        additionalData.size(),
+                                        tagLength != 0,
+                                        tagLength));
+}
+
+// AES Key Generation Algorithm Factories
+
+WebKit::WebCryptoAlgorithm CreateAesCbcKeyGenAlgorithm(unsigned short length) {
+  return CreateAesKeyGenAlgorithm(WebKit::WebCryptoAlgorithmIdAesCbc, length);
+}
+
+WebKit::WebCryptoAlgorithm CreateAesGcmKeyGenAlgorithm(unsigned short length) {
+  return CreateAesKeyGenAlgorithm(WebKit::WebCryptoAlgorithmIdAesGcm, length);
+}
+
+}  // namespace content