platform_hardware_interfaces/rebootescrow/aidl/default/HadamardUtilsTest.cpp
Paul Crowley c675b182b3 Transpose the encoding matrix
Stripe together the encodings from each of the 16 codewords, so that
if a 512-byte DRAM line is knocked out, it affects 256 bits from each
codeword rather than 4096 bits from a single encoded codeword.

Rather than using std::bitset, we directly set and read bits in
the std::vector<uint8_t>, because the striping means that copying it
will now cost not4k in allocation but 64k.

Decode directly to a word, without using list decoding. It seems
we don't need list decoding for the error rates that matter here,
and we never completed the implementation of it anyway.

Declare and test only the full interface, now that it doesn't decompose
quite so neatly.

Bug: 63928581
Test: atest HadamardTest
Change-Id: If022d3f4a8d6fccdf68119d4666f83ce5005bccb
2019-12-20 12:03:21 -08:00

51 lines
1.6 KiB
C++

/*
* Copyright (C) 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdint.h>
#include <random>
#include <gtest/gtest.h>
#include <HadamardUtils.h>
using namespace aidl::android::hardware::rebootescrow::hadamard;
class HadamardTest : public testing::Test {};
static void AddError(std::vector<uint8_t>* data) {
for (size_t i = 0; i < data->size(); i++) {
for (size_t j = 0; j < BYTE_LENGTH; j++) {
if (random() % 100 < 47) {
(*data)[i] ^= (1 << j);
}
}
}
}
TEST_F(HadamardTest, Decode_error_correction) {
constexpr auto iteration = 10;
for (int i = 0; i < iteration; i++) {
std::vector<uint8_t> key;
for (int j = 0; j < KEY_SIZE_IN_BYTES; j++) {
key.emplace_back(random() & 0xff);
}
auto encoded = EncodeKey(key);
ASSERT_EQ(64 * 1024, encoded.size());
AddError(&encoded);
auto decoded = DecodeKey(encoded);
ASSERT_EQ(key, std::vector<uint8_t>(decoded.begin(), decoded.begin() + key.size()));
}
}