vn-verdnaturachat/ios/Pods/MMKVCore/Core/CodedInputDataCrypt.cpp

279 lines
9.7 KiB
C++

/*
* Tencent is pleased to support the open source community by making
* MMKV available.
*
* Copyright (C) 2020 THL A29 Limited, a Tencent company.
* All rights reserved.
*
* Licensed under the BSD 3-Clause License (the "License"); you may not use
* this file except in compliance with the License. You may obtain a copy of
* the License at
*
* https://opensource.org/licenses/BSD-3-Clause
*
* 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 "CodedInputDataCrypt.h"
#include "PBUtility.h"
#include <cerrno>
#include <cstring>
#include <stdexcept>
#ifdef MMKV_APPLE
# if __has_feature(objc_arc)
# error This file must be compiled with MRC. Use -fno-objc-arc flag.
# endif
#endif // MMKV_APPLE
#ifndef MMKV_DISABLE_CRYPT
using namespace std;
namespace mmkv {
CodedInputDataCrypt::CodedInputDataCrypt(const void *oData, size_t length, AESCrypt &crypt)
: m_ptr((uint8_t *) oData), m_size(length), m_position(0), m_decryptPosition(0), m_decrypter(crypt) {
m_decryptBufferSize = AES_KEY_LEN * 2;
m_decryptBufferPosition = static_cast<size_t>(crypt.m_number);
m_decryptBufferDiscardPosition = m_decryptBufferPosition;
m_decryptBufferDecryptLength = m_decryptBufferPosition;
m_decryptBuffer = (uint8_t *) malloc(m_decryptBufferSize);
if (!m_decryptBuffer) {
throw runtime_error(strerror(errno));
}
}
CodedInputDataCrypt::~CodedInputDataCrypt() {
if (m_decryptBuffer) {
free(m_decryptBuffer);
}
}
void CodedInputDataCrypt::seek(size_t addedSize) {
m_position += addedSize;
m_decryptPosition += addedSize;
if (m_position > m_size) {
throw out_of_range("OutOfSpace");
}
assert(m_position % AES_KEY_LEN == m_decrypter.m_number);
}
void CodedInputDataCrypt::consumeBytes(size_t length, bool discardPreData) {
if (discardPreData) {
m_decryptBufferDiscardPosition = m_decryptBufferPosition;
}
auto decryptedBytesLeft = m_decryptBufferDecryptLength - m_decryptBufferPosition;
if (decryptedBytesLeft >= length) {
return;
}
length -= decryptedBytesLeft;
// if there's some data left inside m_decrypter.m_vector, use them first
// it will be faster when always decrypt with (n * AES_KEY_LEN) bytes
if (m_decrypter.m_number != 0) {
auto alignDecrypter = AES_KEY_LEN - m_decrypter.m_number;
// make sure no data left inside m_decrypter.m_vector after decrypt
if (length < alignDecrypter) {
length = alignDecrypter;
} else {
length -= alignDecrypter;
length = ((length + AES_KEY_LEN - 1) / AES_KEY_LEN) * AES_KEY_LEN;
length += alignDecrypter;
}
} else {
length = ((length + AES_KEY_LEN - 1) / AES_KEY_LEN) * AES_KEY_LEN;
}
auto bytesLeftInSrc = m_size - m_decryptPosition;
length = min(bytesLeftInSrc, length);
auto bytesLeftInBuffer = m_decryptBufferSize - m_decryptBufferDecryptLength;
// try move some space
if (bytesLeftInBuffer < length && m_decryptBufferDiscardPosition > 0) {
auto posToMove = (m_decryptBufferDiscardPosition / AES_KEY_LEN) * AES_KEY_LEN;
if (posToMove) {
auto sizeToMove = m_decryptBufferDecryptLength - posToMove;
memmove(m_decryptBuffer, m_decryptBuffer + posToMove, sizeToMove);
m_decryptBufferPosition -= posToMove;
m_decryptBufferDecryptLength -= posToMove;
m_decryptBufferDiscardPosition = 0;
bytesLeftInBuffer = m_decryptBufferSize - m_decryptBufferDecryptLength;
}
}
// still no enough sapce, try realloc()
if (bytesLeftInBuffer < length) {
auto newSize = m_decryptBufferSize + length;
auto newBuffer = realloc(m_decryptBuffer, newSize);
if (!newBuffer) {
throw runtime_error(strerror(errno));
}
m_decryptBuffer = (uint8_t *) newBuffer;
m_decryptBufferSize = newSize;
}
m_decrypter.decrypt(m_ptr + m_decryptPosition, m_decryptBuffer + m_decryptBufferDecryptLength, length);
m_decryptPosition += length;
m_decryptBufferDecryptLength += length;
assert(m_decryptPosition == m_size || m_decrypter.m_number == 0);
}
void CodedInputDataCrypt::skipBytes(size_t length) {
m_position += length;
auto decryptedBytesLeft = m_decryptBufferDecryptLength - m_decryptBufferPosition;
if (decryptedBytesLeft >= length) {
m_decryptBufferPosition += length;
return;
}
length -= decryptedBytesLeft;
// if this happens, we need optimization like the alignDecrypter above
assert(m_decrypter.m_number == 0);
size_t alignSize = ((length + AES_KEY_LEN - 1) / AES_KEY_LEN) * AES_KEY_LEN;
auto bytesLeftInSrc = m_size - m_decryptPosition;
auto size = min(alignSize, bytesLeftInSrc);
decryptedBytesLeft = size - length;
for (size_t index = 0, round = size / AES_KEY_LEN; index < round; index++) {
m_decrypter.decrypt(m_ptr + m_decryptPosition, m_decryptBuffer, AES_KEY_LEN);
m_decryptPosition += AES_KEY_LEN;
size -= AES_KEY_LEN;
}
if (size) {
m_decrypter.decrypt(m_ptr + m_decryptPosition, m_decryptBuffer, size);
m_decryptPosition += size;
m_decryptBufferPosition = size - decryptedBytesLeft;
m_decryptBufferDecryptLength = size;
} else {
m_decryptBufferPosition = AES_KEY_LEN - decryptedBytesLeft;
m_decryptBufferDecryptLength = AES_KEY_LEN;
}
assert(m_decryptBufferPosition <= m_decryptBufferDecryptLength);
assert(m_decryptPosition - m_decryptBufferDecryptLength + m_decryptBufferPosition == m_position);
}
inline void CodedInputDataCrypt::statusBeforeDecrypt(size_t rollbackSize, AESCryptStatus &status) {
rollbackSize += m_decryptBufferDecryptLength - m_decryptBufferPosition;
m_decrypter.statusBeforeDecrypt(m_ptr + m_decryptPosition, m_decryptBuffer + m_decryptBufferDecryptLength,
rollbackSize, status);
}
int8_t CodedInputDataCrypt::readRawByte() {
assert(m_position <= m_decryptPosition);
if (m_position == m_size) {
auto msg = "reach end, m_position: " + to_string(m_position) + ", m_size: " + to_string(m_size);
throw out_of_range(msg);
}
m_position++;
assert(m_decryptBufferPosition < m_decryptBufferSize);
auto *bytes = (int8_t *) m_decryptBuffer;
return bytes[m_decryptBufferPosition++];
}
int32_t CodedInputDataCrypt::readRawVarint32(bool discardPreData) {
consumeBytes(10, discardPreData);
int8_t tmp = this->readRawByte();
if (tmp >= 0) {
return tmp;
}
int32_t result = tmp & 0x7f;
if ((tmp = this->readRawByte()) >= 0) {
result |= tmp << 7;
} else {
result |= (tmp & 0x7f) << 7;
if ((tmp = this->readRawByte()) >= 0) {
result |= tmp << 14;
} else {
result |= (tmp & 0x7f) << 14;
if ((tmp = this->readRawByte()) >= 0) {
result |= tmp << 21;
} else {
result |= (tmp & 0x7f) << 21;
result |= (tmp = this->readRawByte()) << 28;
if (tmp < 0) {
// discard upper 32 bits
for (int i = 0; i < 5; i++) {
if (this->readRawByte() >= 0) {
return result;
}
}
throw invalid_argument("InvalidProtocolBuffer malformed varint32");
}
}
}
}
return result;
}
int32_t CodedInputDataCrypt::readInt32() {
return this->readRawVarint32();
}
# ifndef MMKV_APPLE
string CodedInputDataCrypt::readString(KeyValueHolderCrypt &kvHolder) {
kvHolder.offset = static_cast<uint32_t>(m_position);
int32_t size = this->readRawVarint32(true);
if (size < 0) {
throw length_error("InvalidProtocolBuffer negativeSize");
}
auto s_size = static_cast<size_t>(size);
if (s_size <= m_size - m_position) {
consumeBytes(s_size);
kvHolder.keySize = static_cast<uint16_t>(s_size);
string result((char *) (m_decryptBuffer + m_decryptBufferPosition), s_size);
m_position += s_size;
m_decryptBufferPosition += s_size;
return result;
} else {
throw out_of_range("InvalidProtocolBuffer truncatedMessage");
}
}
# endif
void CodedInputDataCrypt::readData(KeyValueHolderCrypt &kvHolder) {
int32_t size = this->readRawVarint32();
if (size < 0) {
throw length_error("InvalidProtocolBuffer negativeSize");
}
auto s_size = static_cast<size_t>(size);
if (s_size <= m_size - m_position) {
if (KeyValueHolderCrypt::isValueStoredAsOffset(s_size)) {
kvHolder.type = KeyValueHolderType_Offset;
kvHolder.valueSize = static_cast<uint32_t>(s_size);
kvHolder.pbKeyValueSize =
static_cast<uint8_t>(pbRawVarint32Size(kvHolder.valueSize) + pbRawVarint32Size(kvHolder.keySize));
size_t rollbackSize = kvHolder.pbKeyValueSize + kvHolder.keySize;
statusBeforeDecrypt(rollbackSize, kvHolder.cryptStatus);
skipBytes(s_size);
} else {
consumeBytes(s_size);
kvHolder.type = KeyValueHolderType_Direct;
kvHolder = KeyValueHolderCrypt(m_decryptBuffer + m_decryptBufferPosition, s_size);
m_decryptBufferPosition += s_size;
m_position += s_size;
}
} else {
throw out_of_range("InvalidProtocolBuffer truncatedMessage");
}
}
} // namespace mmkv
#endif // MMKV_DISABLE_CRYPT