[webcrypto] JWK: Updated import(ext, key_ops) and added export of symmetric keys

content/renderer/webcrypto/webcrypto_util.cc

 // Copyright 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 "content/renderer/webcrypto/webcrypto_util.h"
 
 #include "base/base64.h"
 #include "base/logging.h"
+#include "base/strings/stringprintf.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithm.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
 #include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
 
 namespace content {
 
 namespace webcrypto {
 
 bool Status::IsError() const { return type_ == TYPE_ERROR; }
 
@@ skipping 21 matching lines @@
                                          const std::string& expected_type) {
   return Status("The JWK property \"" + property + "\" must be a " +
                 expected_type);
 }
 
 Status Status::ErrorJwkBase64Decode(const std::string& property) {
   return Status("The JWK property \"" + property +
                 "\" could not be base64 decoded");
 }
 
-Status Status::ErrorJwkExtractableInconsistent() {
+Status Status::ErrorJwkExtInconsistent() {
   return Status(
-      "The \"extractable\" property of the JWK dictionary is "
-      "inconsistent what that specified by the Web Crypto call");
+      "The \"ext\" property of the JWK dictionary is inconsistent what that "
+      "specified by the Web Crypto call");
 }
 
 Status Status::ErrorJwkUnrecognizedAlgorithm() {
   return Status("The JWK \"alg\" property was not recognized");
 }
 
 Status Status::ErrorJwkAlgorithmInconsistent() {
   return Status(
       "The JWK \"alg\" property was inconsistent with that specified "
       "by the Web Crypto call");
 }
 
 Status Status::ErrorJwkAlgorithmMissing() {
   return Status(
       "The JWK optional \"alg\" property is missing or not a string, "
       "and one wasn't specified by the Web Crypto call");
 }
 
-Status Status::ErrorJwkUnrecognizedUsage() {
+Status Status::ErrorJwkUnrecognizedUse() {
   return Status("The JWK \"use\" property could not be parsed");
 }
 
-Status Status::ErrorJwkUsageInconsistent() {
+Status Status::ErrorJwkUnrecognizedKeyop() {
+  return Status("The JWK \"key_ops\" property could not be parsed");
+}
+
+Status Status::ErrorJwkUseInconsistent() {
   return Status(
       "The JWK \"use\" property was inconsistent with that specified "
       "by the Web Crypto call. The JWK usage must be a superset of "
       "those requested");
 }
 
+Status Status::ErrorJwkKeyopsInconsistent() {
+  return Status(
+      "The JWK \"key_ops\" property was inconsistent with that "
+      "specified by the Web Crypto call. The JWK usage must be a "
+      "superset of those requested");
+}
+
+Status Status::ErrorJwkUseAndKeyopsInconsistent() {
+  return Status(
+      "The JWK \"use\" and \"key_ops\" properties were both found "
+      "but are inconsistent with each other.");
+}
+
 Status Status::ErrorJwkRsaPrivateKeyUnsupported() {
   return Status(
       "JWK RSA key contained \"d\" property: Private key import is "
       "not yet supported");
 }
 
 Status Status::ErrorJwkUnrecognizedKty() {
   return Status("The JWK \"kty\" property was unrecognized");
 }
 
 Status Status::ErrorJwkIncorrectKeyLength() {
   return Status(
       "The JWK \"k\" property did not include the right length "
       "of key data for the given algorithm.");
 }
 
+Status Status::ErrorJwkUnsupportedHmacHash() {
+  return Status("JWK does not support HMAC with this inner hash.");
+}
+
 Status Status::ErrorImportEmptyKeyData() {
   return Status("No key data was provided");
 }
 
 Status Status::ErrorUnexpectedKeyType() {
   return Status("The key is not of the expected type");
 }
 
 Status Status::ErrorIncorrectSizeAesCbcIv() {
   return Status("The \"iv\" has an unexpected length -- must be 16 bytes");
@@ skipping 103 matching lines @@
 // transformation including adding padding if required, and then call a base64
 // decoder.
 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);
 }
 
+// Produces an unpadded 'base64url' encoding of the input data, using the
+// inverse of the process above.
+void Base64EncodeUrlSafe(const base::StringPiece& input, std::string* output) {
+  base::Base64Encode(input, output);
+  std::replace(output->begin(), output->end(), '+', '-');
+  std::replace(output->begin(), output->end(), '/', '_');
+  output->erase(std::remove(output->begin(), output->end(), '='),
+                output->end());
+}
+
+// Composes a Web Crypto usage mask from an array of JWK key_ops values.
+Status GetUsagesFromJwkKeyOps(base::ListValue* jwk_key_ops_value,
+                              blink::WebCryptoKeyUsageMask* jwk_key_ops_mask) {
+  for (size_t i = 0; i < jwk_key_ops_value->GetSize(); ++i) {
+    std::string key_op;
+    if (!jwk_key_ops_value->GetString(i, &key_op))
+      return Status::ErrorJwkPropertyWrongType(
+          base::StringPrintf("key_ops[%d]", static_cast<int>(i)), "string");
+    if (key_op == "encrypt")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageEncrypt;
+    else if (key_op == "decrypt")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageDecrypt;
+    else if (key_op == "sign")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageSign;
+    else if (key_op == "verify")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageVerify;
+    else if (key_op == "wrapKey")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageWrapKey;
+    else if (key_op == "unwrapKey")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageUnwrapKey;
+    else if (key_op == "deriveKey")
+      *jwk_key_ops_mask |= blink::WebCryptoKeyUsageDeriveKey;
+    else
+      return Status::ErrorJwkUnrecognizedKeyop();
+    // TODO(padolph): Add 'deriveBits' once supported by Blink.
+  }
+  return Status::Success();
+}
+
 bool IsHashAlgorithm(blink::WebCryptoAlgorithmId alg_id) {
   return alg_id == blink::WebCryptoAlgorithmIdSha1 ||
          alg_id == blink::WebCryptoAlgorithmIdSha224 ||
          alg_id == blink::WebCryptoAlgorithmIdSha256 ||
          alg_id == blink::WebCryptoAlgorithmIdSha384 ||
          alg_id == blink::WebCryptoAlgorithmIdSha512;
 }
 
 blink::WebCryptoAlgorithm GetInnerHashAlgorithm(
     const blink::WebCryptoAlgorithm& algorithm) {
@@ skipping 79 matching lines @@
           new blink::WebCryptoAesKeyAlgorithmParams(keylen_bytes * 8));
       return true;
     default:
       return false;
   }
 }
 
 }  // namespace webcrypto
 
 }  // namespace content