#include "config.h"
#include "CryptoKeyHMAC.h"
#if ENABLE(WEB_CRYPTO)
#include "CryptoAlgorithmHmacKeyParams.h"
#include "CryptoAlgorithmRegistry.h"
#include "ExceptionOr.h"
#include "JsonWebKey.h"
#include <wtf/text/Base64.h>
#include <wtf/text/WTFString.h>
namespace WebCore {
static size_t getKeyLengthFromHash(CryptoAlgorithmIdentifier hash)
{
switch (hash) {
case CryptoAlgorithmIdentifier::SHA_1:
case CryptoAlgorithmIdentifier::SHA_224:
case CryptoAlgorithmIdentifier::SHA_256:
return 512;
case CryptoAlgorithmIdentifier::SHA_384:
case CryptoAlgorithmIdentifier::SHA_512:
return 1024;
default:
ASSERT_NOT_REACHED();
return 0;
}
}
CryptoKeyHMAC::CryptoKeyHMAC(const Vector<uint8_t>& key, CryptoAlgorithmIdentifier hash, bool extractable, CryptoKeyUsageBitmap usage)
: CryptoKey(CryptoAlgorithmIdentifier::HMAC, CryptoKeyType::Secret, extractable, usage)
, m_hash(hash)
, m_key(key)
{
}
CryptoKeyHMAC::CryptoKeyHMAC(Vector<uint8_t>&& key, CryptoAlgorithmIdentifier hash, bool extractable, CryptoKeyUsageBitmap usage)
: CryptoKey(CryptoAlgorithmIdentifier::HMAC, CryptoKeyType::Secret, extractable, usage)
, m_hash(hash)
, m_key(WTFMove(key))
{
}
CryptoKeyHMAC::~CryptoKeyHMAC() = default;
RefPtr<CryptoKeyHMAC> CryptoKeyHMAC::generate(size_t lengthBits, CryptoAlgorithmIdentifier hash, bool extractable, CryptoKeyUsageBitmap usages)
{
if (!lengthBits) {
lengthBits = getKeyLengthFromHash(hash);
if (!lengthBits)
return nullptr;
}
if (lengthBits % 8)
return nullptr;
return adoptRef(new CryptoKeyHMAC(randomData(lengthBits / 8), hash, extractable, usages));
}
RefPtr<CryptoKeyHMAC> CryptoKeyHMAC::importRaw(size_t lengthBits, CryptoAlgorithmIdentifier hash, Vector<uint8_t>&& keyData, bool extractable, CryptoKeyUsageBitmap usages)
{
size_t length = keyData.size() * 8;
if (!length)
return nullptr;
if (lengthBits && lengthBits != length)
return nullptr;
return adoptRef(new CryptoKeyHMAC(WTFMove(keyData), hash, extractable, usages));
}
RefPtr<CryptoKeyHMAC> CryptoKeyHMAC::importJwk(size_t lengthBits, CryptoAlgorithmIdentifier hash, JsonWebKey&& keyData, bool extractable, CryptoKeyUsageBitmap usages, CheckAlgCallback&& callback)
{
if (keyData.kty != "oct")
return nullptr;
if (keyData.k.isNull())
return nullptr;
Vector<uint8_t> octetSequence;
if (!base64URLDecode(keyData.k, octetSequence))
return nullptr;
if (!callback(hash, keyData.alg))
return nullptr;
if (usages && !keyData.use.isNull() && keyData.use != "sig")
return nullptr;
if (keyData.key_ops && ((keyData.usages & usages) != usages))
return nullptr;
if (keyData.ext && !keyData.ext.value() && extractable)
return nullptr;
return CryptoKeyHMAC::importRaw(lengthBits, hash, WTFMove(octetSequence), extractable, usages);
}
JsonWebKey CryptoKeyHMAC::exportJwk() const
{
JsonWebKey result;
result.kty = "oct";
result.k = base64URLEncode(m_key);
result.key_ops = usages();
result.ext = extractable();
return result;
}
ExceptionOr<size_t> CryptoKeyHMAC::getKeyLength(const CryptoAlgorithmParameters& parameters)
{
auto& aesParameters = downcast<CryptoAlgorithmHmacKeyParams>(parameters);
size_t result = aesParameters.length ? *(aesParameters.length) : getKeyLengthFromHash(aesParameters.hashIdentifier);
if (result)
return result;
return Exception { TypeError };
}
auto CryptoKeyHMAC::algorithm() const -> KeyAlgorithm
{
CryptoHmacKeyAlgorithm result;
result.name = CryptoAlgorithmRegistry::singleton().name(algorithmIdentifier());
result.hash.name = CryptoAlgorithmRegistry::singleton().name(m_hash);
result.length = m_key.size() * 8;
return result;
}
}
#endif // ENABLE(WEB_CRYPTO)