dom/base/Crypto.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   3  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   4 #include "Crypto.h"
   5 #include "jsfriendapi.h"
   6 #include "nsCOMPtr.h"
   7 #include "nsIRandomGenerator.h"
   8 #include "MainThreadUtils.h"
   9 #include "nsXULAppAPI.h"
  10
  11 #include "mozilla/dom/ContentChild.h"
  12 #include "mozilla/dom/CryptoBinding.h"
  13 #include "nsServiceManagerUtils.h"
  14
  15 using mozilla::dom::ContentChild;
  16
  17 namespace mozilla {
  18 namespace dom {
  19
  20 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(Crypto)
  21   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  22   NS_INTERFACE_MAP_ENTRY(nsISupports)
  23   NS_INTERFACE_MAP_ENTRY(nsIDOMCrypto)
  24 NS_INTERFACE_MAP_END
  25
  26 NS_IMPL_CYCLE_COLLECTING_ADDREF(Crypto)
  27 NS_IMPL_CYCLE_COLLECTING_RELEASE(Crypto)
  28
  29 NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(Crypto, mParent, mSubtle)
  30
  31 Crypto::Crypto()
  32 {
  33   MOZ_COUNT_CTOR(Crypto);
  34 }
  35
  36 Crypto::~Crypto()
  37 {
  38   MOZ_COUNT_DTOR(Crypto);
  39 }
  40
  41 void
  42 Crypto::Init(nsIGlobalObject* aParent)
  43 {
  44   mParent = do_QueryInterface(aParent);
  45   MOZ_ASSERT(mParent);
  46 }
  47
  48 /* virtual */ JSObject*
  49 Crypto::WrapObject(JSContext* aCx)
  50 {
  51   return CryptoBinding::Wrap(aCx, this);
  52 }
  53
  54 void
  55 Crypto::GetRandomValues(JSContext* aCx, const ArrayBufferView& aArray,
  56                         JS::MutableHandle<JSObject*> aRetval,
  57                         ErrorResult& aRv)
  58 {
  59   NS_ABORT_IF_FALSE(NS_IsMainThread(), "Called on the wrong thread");
  60
  61   JS::Rooted<JSObject*> view(aCx, aArray.Obj());
  62
  63   // Throw if the wrong type of ArrayBufferView is passed in
  64   // (Part of the Web Crypto API spec)
  65   switch (JS_GetArrayBufferViewType(view)) {
  66     case js::Scalar::Int8:
  67     case js::Scalar::Uint8:
  68     case js::Scalar::Uint8Clamped:
  69     case js::Scalar::Int16:
  70     case js::Scalar::Uint16:
  71     case js::Scalar::Int32:
  72     case js::Scalar::Uint32:
  73       break;
  74     default:
  75       aRv.Throw(NS_ERROR_DOM_TYPE_MISMATCH_ERR);
  76       return;
  77   }
  78
  79   aArray.ComputeLengthAndData();
  80   uint32_t dataLen = aArray.Length();
  81   if (dataLen == 0) {
  82     NS_WARNING("ArrayBufferView length is 0, cannot continue");
  83     aRetval.set(view);
  84     return;
  85   } else if (dataLen > 65536) {
  86     aRv.Throw(NS_ERROR_DOM_QUOTA_EXCEEDED_ERR);
  87     return;
  88   }
  89
  90   uint8_t* data = aArray.Data();
  91
  92   if (XRE_GetProcessType() != GeckoProcessType_Default) {
  93     InfallibleTArray<uint8_t> randomValues;
  94     // Tell the parent process to generate random values via PContent
  95     ContentChild* cc = ContentChild::GetSingleton();
  96     if (!cc->SendGetRandomValues(dataLen, &randomValues) ||
  97         randomValues.Length() == 0) {
  98       aRv.Throw(NS_ERROR_FAILURE);
  99       return;
 100     }
 101     NS_ASSERTION(dataLen == randomValues.Length(),
 102                  "Invalid length returned from parent process!");
 103     memcpy(data, randomValues.Elements(), dataLen);
 104   } else {
 105     uint8_t *buf = GetRandomValues(dataLen);
 106
 107     if (!buf) {
 108       aRv.Throw(NS_ERROR_FAILURE);
 109       return;
 110     }
 111
 112     memcpy(data, buf, dataLen);
 113     NS_Free(buf);
 114   }
 115
 116   aRetval.set(view);
 117 }
 118
 119 SubtleCrypto*
 120 Crypto::Subtle()
 121 {
 122   if(!mSubtle) {
 123     mSubtle = new SubtleCrypto(GetParentObject());
 124   }
 125   return mSubtle;
 126 }
 127
 128 /* static */ uint8_t*
 129 Crypto::GetRandomValues(uint32_t aLength)
 130 {
 131   nsCOMPtr<nsIRandomGenerator> randomGenerator;
 132   nsresult rv;
 133   randomGenerator = do_GetService("@mozilla.org/security/random-generator;1");
 134   NS_ENSURE_TRUE(randomGenerator, nullptr);
 135
 136   uint8_t* buf;
 137   rv = randomGenerator->GenerateRandomBytes(aLength, &buf);
 138
 139   NS_ENSURE_SUCCESS(rv, nullptr);
 140
 141   return buf;
 142 }
 143
 144 } // namespace dom
 145 } // namespace mozilla