repertory/support/src/utils/encryption.cpp

118 lines
4.2 KiB
C++

/*
Copyright <2018-2024> <scott.e.graves@protonmail.com>
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
#if defined(PROJECT_ENABLE_LIBSODIUM) && defined(PROJECT_ENABLE_BOOST)
#include "utils/encryption.hpp"
#include "utils/collection.hpp"
#include "utils/encrypting_reader.hpp"
namespace repertory::utils::encryption {
auto decrypt_file_path(std::string_view encryption_token,
std::string &file_path) -> bool {
std::string decrypted_file_path{};
for (const auto &part : std::filesystem::path(file_path)) {
auto file_name = part.string();
if (file_name == "/") {
continue;
}
auto res = decrypt_file_name(encryption_token, file_name);
if (not res) {
return res;
}
decrypted_file_path += '/' + file_name;
}
file_path = decrypted_file_path;
return true;
}
auto decrypt_file_name(std::string_view encryption_token,
std::string &file_name) -> bool {
data_buffer buffer;
if (not utils::collection::from_hex_string(file_name, buffer)) {
return false;
}
file_name.clear();
if (not utils::encryption::decrypt_data(encryption_token, buffer,
file_name)) {
return false;
}
return true;
}
#if defined(PROJECT_ENABLE_CURL)
auto read_encrypted_range(const http_range &range,
const utils::encryption::hash_256_t &key,
reader_func_t reader_func, std::uint64_t total_size,
data_buffer &data) -> bool {
const auto encrypted_chunk_size =
utils::encryption::encrypting_reader::get_encrypted_chunk_size();
const auto data_chunk_size =
utils::encryption::encrypting_reader::get_data_chunk_size();
const auto start_chunk =
static_cast<std::size_t>(range.begin / data_chunk_size);
const auto end_chunk = static_cast<std::size_t>(range.end / data_chunk_size);
auto remain = range.end - range.begin + 1U;
auto source_offset = static_cast<std::size_t>(range.begin % data_chunk_size);
for (std::size_t chunk = start_chunk; chunk <= end_chunk; chunk++) {
data_buffer cypher;
const auto start_offset = chunk * encrypted_chunk_size;
const auto end_offset = std::min(
start_offset + (total_size - (chunk * data_chunk_size)) +
encryption_header_size - 1U,
static_cast<std::uint64_t>(start_offset + encrypted_chunk_size - 1U));
if (not reader_func(cypher, start_offset, end_offset)) {
return false;
}
data_buffer source_buffer;
if (not utils::encryption::decrypt_data(key, cypher, source_buffer)) {
return false;
}
cypher.clear();
const auto data_size = static_cast<std::size_t>(std::min(
remain, static_cast<std::uint64_t>(data_chunk_size - source_offset)));
std::copy(std::next(source_buffer.begin(),
static_cast<std::int64_t>(source_offset)),
std::next(source_buffer.begin(),
static_cast<std::int64_t>(source_offset + data_size)),
std::back_inserter(data));
remain -= data_size;
source_offset = 0U;
}
return true;
}
#endif // defined(PROJECT_ENABLE_CURL)
} // namespace repertory::utils::encryption
#endif // defined(PROJECT_ENABLE_LIBSODIUM) && defined (PROJECT_ENABLE_BOOST)