third_party/WebKit/Source/modules/crypto/Crypto.cpp

/*
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#include "modules/crypto/Crypto.h"

#include "bindings/core/v8/ExceptionState.h"
#include "core/dom/ExceptionCode.h"
#include "core/typed_arrays/DOMArrayBufferView.h"
#include "platform/wtf/CryptographicallyRandomNumber.h"

namespace blink {

namespace {

bool IsIntegerArray(DOMArrayBufferView* array) {
  DOMArrayBufferView::ViewType type = array->GetType();
  return type == DOMArrayBufferView::kTypeInt8 ||
         type == DOMArrayBufferView::kTypeUint8 ||
         type == DOMArrayBufferView::kTypeUint8Clamped ||
         type == DOMArrayBufferView::kTypeInt16 ||
         type == DOMArrayBufferView::kTypeUint16 ||
         type == DOMArrayBufferView::kTypeInt32 ||
         type == DOMArrayBufferView::kTypeUint32;
}

}  // namespace

NotShared<DOMArrayBufferView> Crypto::getRandomValues(
    NotShared<DOMArrayBufferView> array,
    ExceptionState& exception_state) {
  DCHECK(array);
  if (!IsIntegerArray(array.View())) {
    exception_state.ThrowDOMException(
        kTypeMismatchError,
        String::Format("The provided ArrayBufferView is of type '%s', which is "
                       "not an integer array type.",
                       array.View()->TypeName()));
    return NotShared<DOMArrayBufferView>(nullptr);
  }
  if (array.View()->byteLength() > 65536) {
    exception_state.ThrowDOMException(
        kQuotaExceededError,
        String::Format("The ArrayBufferView's byte length (%u) exceeds the "
                       "number of bytes of entropy available via this API "
                       "(65536).",
                       array.View()->byteLength()));
    return NotShared<DOMArrayBufferView>(nullptr);
  }
  CryptographicallyRandomValues(array.View()->BaseAddress(),
                                array.View()->byteLength());
  return array;
}

SubtleCrypto* Crypto::subtle() {
  if (!subtle_crypto_)
    subtle_crypto_ = SubtleCrypto::Create();
  return subtle_crypto_.Get();
}

void Crypto::Trace(blink::Visitor* visitor) {
  visitor->Trace(subtle_crypto_);
  ScriptWrappable::Trace(visitor);
}

}  // namespace blink