blob: f7c8aacd3e232ad4ed170c7d7551dd6b5b48c6de [file] [log] [blame]
/*
* Copyright (C) 2017 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "CommonCryptoDERUtilities.h"
#if ENABLE(SUBTLE_CRYPTO)
namespace WebCore {
size_t bytesUsedToEncodedLength(uint8_t octet)
{
if (octet < MaxLengthInOneByte)
return 1;
return octet - MaxLengthInOneByte + 1;
}
size_t extraBytesNeededForEncodedLength(size_t length)
{
if (!length)
return 0;
size_t result = 1;
while (result < sizeof(length) && length >= (1 << (result * 8)))
result += 1;
return result;
}
void addEncodedASN1Length(Vector<uint8_t>& in, size_t length)
{
if (length < MaxLengthInOneByte) {
in.append(length);
return;
}
size_t extraBytes = extraBytesNeededForEncodedLength(length);
in.append(128 + extraBytes); // 128 is used to set the first bit of this byte.
size_t lastPosition = in.size() + extraBytes - 1;
in.grow(in.size() + extraBytes);
for (size_t i = 0; i < extraBytes; i++) {
in[lastPosition - i] = length & 0xff;
length = length >> 8;
}
}
size_t bytesNeededForEncodedLength(size_t length)
{
if (length < MaxLengthInOneByte)
return 1;
return 1 + extraBytesNeededForEncodedLength(length);
}
} // namespace WebCore
#endif // ENABLE(SUBTLE_CRYPTO)