CryptoAlgorithmPBKDF2GCrypt.cpp   [plain text]


/*
 * Copyright (C) 2017 Apple Inc. All rights reserved.
 * Copyright (C) 2017 Metrological Group B.V.
 * Copyright (C) 2017 Igalia S.L.
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#include "config.h"
#include "CryptoAlgorithmPBKDF2.h"

#if ENABLE(SUBTLE_CRYPTO)

#include "CryptoAlgorithmPbkdf2Params.h"
#include "CryptoKeyRaw.h"
#include "ExceptionCode.h"
#include "GCryptUtilities.h"
#include "ScriptExecutionContext.h"

namespace WebCore {

static std::optional<Vector<uint8_t>> gcryptDeriveBits(const Vector<uint8_t>& keyData, const Vector<uint8_t>& saltData, CryptoAlgorithmIdentifier hashIdentifier, size_t iterations, size_t length)
{
    // Determine the hash algorithm that will be used for derivation.
    auto hashAlgorithm = digestAlgorithm(hashIdentifier);
    if (!hashAlgorithm)
        return std::nullopt;

    // Length, in bits, is a multiple of 8, as guaranteed by CryptoAlgorithmPBKDF2::deriveBits().
    ASSERT(!(length % 8));

    // Derive bits using PBKDF2, the specified hash algorithm, salt data and iteration count.
    Vector<uint8_t> result(length / 8);
    gcry_error_t error = gcry_kdf_derive(keyData.data(), keyData.size(), GCRY_KDF_PBKDF2, *hashAlgorithm, saltData.data(), saltData.size(), iterations, result.size(), result.data());
    if (error != GPG_ERR_NO_ERROR) {
        PAL::GCrypt::logError(error);
        return std::nullopt;
    }

    return result;
}

void CryptoAlgorithmPBKDF2::platformDeriveBits(std::unique_ptr<CryptoAlgorithmParameters>&& parameters, Ref<CryptoKey>&& key, size_t length, VectorCallback&& callback, ExceptionCallback&& exceptionCallback, ScriptExecutionContext& context, WorkQueue& workQueue)
{
    context.ref();
    workQueue.dispatch(
        [parameters = WTFMove(parameters), key = WTFMove(key), length, callback = WTFMove(callback), exceptionCallback = WTFMove(exceptionCallback), &context]() mutable {
            auto& pbkdf2Parameters = downcast<CryptoAlgorithmPbkdf2Params>(*parameters);
            auto& rawKey = downcast<CryptoKeyRaw>(key.get());

            auto output = gcryptDeriveBits(rawKey.key(), pbkdf2Parameters.saltVector(), pbkdf2Parameters.hashIdentifier, pbkdf2Parameters.iterations, length);
            if (!output) {
                // We should only dereference callbacks after being back to the Document/Worker threads.
                context.postTask(
                    [callback = WTFMove(callback), exceptionCallback = WTFMove(exceptionCallback)](ScriptExecutionContext& context) {
                        exceptionCallback(OperationError);
                        context.deref();
                    });
                return;
            }

            // We should only dereference callbacks after being back to the Document/Worker threads.
            context.postTask(
                [output = WTFMove(*output), callback = WTFMove(callback), exceptionCallback = WTFMove(exceptionCallback)](ScriptExecutionContext& context) {
                    callback(output);
                    context.deref();
                });
        });
}

} // namespace WebCore

#endif // ENABLE(SUBTLE_CRYPTO)