gecko-dev/dom/crypto/CryptoBuffer.cpp
Birunthan Mohanathas ea4a3be55c Bug 968520 - Use FallibleTArray::Clear instead of SetLength(0). r=froydnj
This preemptively fixes the upcoming -Wunused-result warnings due to unchecked
SetLength calls.
2015-05-28 11:07:43 -07:00

187 lines
4.4 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "CryptoBuffer.h"
#include "secitem.h"
#include "mozilla/Base64.h"
#include "mozilla/dom/UnionTypes.h"
namespace mozilla {
namespace dom {
uint8_t*
CryptoBuffer::Assign(const CryptoBuffer& aData)
{
// Same as in nsTArray_Impl::operator=, but return the value
// returned from ReplaceElementsAt to enable OOM detection
return ReplaceElementsAt(0, Length(), aData.Elements(), aData.Length(),
fallible);
}
uint8_t*
CryptoBuffer::Assign(const uint8_t* aData, uint32_t aLength)
{
return ReplaceElementsAt(0, Length(), aData, aLength, fallible);
}
uint8_t*
CryptoBuffer::Assign(const SECItem* aItem)
{
MOZ_ASSERT(aItem);
return Assign(aItem->data, aItem->len);
}
uint8_t*
CryptoBuffer::Assign(const ArrayBuffer& aData)
{
aData.ComputeLengthAndData();
return Assign(aData.Data(), aData.Length());
}
uint8_t*
CryptoBuffer::Assign(const ArrayBufferView& aData)
{
aData.ComputeLengthAndData();
return Assign(aData.Data(), aData.Length());
}
uint8_t*
CryptoBuffer::Assign(const ArrayBufferViewOrArrayBuffer& aData)
{
if (aData.IsArrayBufferView()) {
return Assign(aData.GetAsArrayBufferView());
} else if (aData.IsArrayBuffer()) {
return Assign(aData.GetAsArrayBuffer());
}
// If your union is uninitialized, something's wrong
MOZ_ASSERT(false);
Clear();
return nullptr;
}
uint8_t*
CryptoBuffer::Assign(const OwningArrayBufferViewOrArrayBuffer& aData)
{
if (aData.IsArrayBufferView()) {
return Assign(aData.GetAsArrayBufferView());
} else if (aData.IsArrayBuffer()) {
return Assign(aData.GetAsArrayBuffer());
}
// If your union is uninitialized, something's wrong
MOZ_ASSERT(false);
Clear();
return nullptr;
}
// Helpers to encode/decode JWK's special flavor of Base64
// * No whitespace
// * No padding
// * URL-safe character set
nsresult
CryptoBuffer::FromJwkBase64(const nsString& aBase64)
{
NS_ConvertUTF16toUTF8 temp(aBase64);
temp.StripWhitespace();
// Re-add padding
if (temp.Length() % 4 == 3) {
temp.AppendLiteral("=");
} else if (temp.Length() % 4 == 2) {
temp.AppendLiteral("==");
} if (temp.Length() % 4 == 1) {
return NS_ERROR_FAILURE; // bad Base64
}
// Translate from URL-safe character set to normal
temp.ReplaceChar('-', '+');
temp.ReplaceChar('_', '/');
// Perform the actual base64 decode
nsCString binaryData;
nsresult rv = Base64Decode(temp, binaryData);
NS_ENSURE_SUCCESS(rv, rv);
if (!Assign((const uint8_t*) binaryData.BeginReading(),
binaryData.Length())) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
nsresult
CryptoBuffer::ToJwkBase64(nsString& aBase64)
{
// Shortcut for the empty octet string
if (Length() == 0) {
aBase64.Truncate();
return NS_OK;
}
// Perform the actual base64 encode
nsCString base64;
nsDependentCSubstring binaryData((const char*) Elements(),
(const char*) (Elements() + Length()));
nsresult rv = Base64Encode(binaryData, base64);
NS_ENSURE_SUCCESS(rv, rv);
// Strip padding
base64.Trim("=");
// Translate to the URL-safe charset
base64.ReplaceChar('+', '-');
base64.ReplaceChar('/', '_');
if (base64.FindCharInSet("+/", 0) != kNotFound) {
return NS_ERROR_FAILURE;
}
CopyASCIItoUTF16(base64, aBase64);
return NS_OK;
}
bool
CryptoBuffer::ToSECItem(PLArenaPool *aArena, SECItem* aItem) const
{
aItem->type = siBuffer;
aItem->data = nullptr;
if (!::SECITEM_AllocItem(aArena, aItem, Length())) {
return false;
}
memcpy(aItem->data, Elements(), Length());
return true;
}
JSObject*
CryptoBuffer::ToUint8Array(JSContext* aCx) const
{
return Uint8Array::Create(aCx, Length(), Elements());
}
// "BigInt" comes from the WebCrypto spec
// ("unsigned long" isn't very "big", of course)
// Likewise, the spec calls for big-endian ints
bool
CryptoBuffer::GetBigIntValue(unsigned long& aRetVal)
{
if (Length() > sizeof(aRetVal)) {
return false;
}
aRetVal = 0;
for (size_t i=0; i < Length(); ++i) {
aRetVal = (aRetVal << 8) + ElementAt(i);
}
return true;
}
} // namespace dom
} // namespace mozilla