dom/base/Crypto.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6 #include "Crypto.h"
   7 #include "jsfriendapi.h"
   8 #include "js/experimental/TypedData.h"  // JS_GetArrayBufferViewType
   9 #include "nsCOMPtr.h"
  10 #include "nsIRandomGenerator.h"
  11 #include "MainThreadUtils.h"
  12 #include "nsXULAppAPI.h"
  13
  14 #include "mozilla/dom/ContentChild.h"
  15 #include "mozilla/dom/CryptoBinding.h"
  16 #include "nsServiceManagerUtils.h"
  17
  18 using mozilla::dom::ContentChild;
  19
  20 namespace mozilla {
  21 namespace dom {
  22
  23 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(Crypto)
  24   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  25   NS_INTERFACE_MAP_ENTRY(nsISupports)
  26 NS_INTERFACE_MAP_END
  27
  28 NS_IMPL_CYCLE_COLLECTING_ADDREF(Crypto)
  29 NS_IMPL_CYCLE_COLLECTING_RELEASE(Crypto)
  30
  31 NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(Crypto, mParent, mSubtle)
  32
  33 Crypto::Crypto(nsIGlobalObject* aParent) : mParent(aParent) {}
  34
  35 Crypto::~Crypto() = default;
  36
  37 /* virtual */
  38 JSObject* Crypto::WrapObject(JSContext* aCx,
  39                              JS::Handle<JSObject*> aGivenProto) {
  40   return Crypto_Binding::Wrap(aCx, this, aGivenProto);
  41 }
  42
  43 void Crypto::GetRandomValues(JSContext* aCx, const ArrayBufferView& aArray,
  44                              JS::MutableHandle<JSObject*> aRetval,
  45                              ErrorResult& aRv) {
  46   JS::Rooted<JSObject*> view(aCx, aArray.Obj());
  47
  48   // Throw if the wrong type of ArrayBufferView is passed in
  49   // (Part of the Web Crypto API spec)
  50   switch (JS_GetArrayBufferViewType(view)) {
  51     case js::Scalar::Int8:
  52     case js::Scalar::Uint8:
  53     case js::Scalar::Uint8Clamped:
  54     case js::Scalar::Int16:
  55     case js::Scalar::Uint16:
  56     case js::Scalar::Int32:
  57     case js::Scalar::Uint32:
  58       break;
  59     default:
  60       aRv.Throw(NS_ERROR_DOM_TYPE_MISMATCH_ERR);
  61       return;
  62   }
  63
  64   aArray.ComputeState();
  65   uint32_t dataLen = aArray.Length();
  66   if (dataLen == 0) {
  67     NS_WARNING("ArrayBufferView length is 0, cannot continue");
  68     aRetval.set(view);
  69     return;
  70   } else if (dataLen > 65536) {
  71     aRv.Throw(NS_ERROR_DOM_QUOTA_EXCEEDED_ERR);
  72     return;
  73   }
  74
  75   nsCOMPtr<nsIRandomGenerator> randomGenerator =
  76       do_GetService("@mozilla.org/security/random-generator;1");
  77   if (!randomGenerator) {
  78     aRv.Throw(NS_ERROR_DOM_OPERATION_ERR);
  79     return;
  80   }
  81
  82   uint8_t* buf;
  83   nsresult rv = randomGenerator->GenerateRandomBytes(dataLen, &buf);
  84   if (NS_FAILED(rv) || !buf) {
  85     aRv.Throw(NS_ERROR_DOM_OPERATION_ERR);
  86     return;
  87   }
  88
  89   // Copy random bytes to ABV.
  90   memcpy(aArray.Data(), buf, dataLen);
  91   free(buf);
  92
  93   aRetval.set(view);
  94 }
  95
  96 SubtleCrypto* Crypto::Subtle() {
  97   if (!mSubtle) {
  98     mSubtle = new SubtleCrypto(GetParentObject());
  99   }
 100   return mSubtle;
 101 }
 102
 103 }  // namespace dom
 104 }  // namespace mozilla