diff options
Diffstat (limited to 'contrib/epee/src/wipeable_string.cpp')
-rw-r--r-- | contrib/epee/src/wipeable_string.cpp | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/contrib/epee/src/wipeable_string.cpp b/contrib/epee/src/wipeable_string.cpp new file mode 100644 index 000000000..894c47bbd --- /dev/null +++ b/contrib/epee/src/wipeable_string.cpp @@ -0,0 +1,147 @@ +// Copyright (c) 2017, The Monero Project +// +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without modification, are +// permitted provided that the following conditions are met: +// +// 1. Redistributions of source code must retain the above copyright notice, this list of +// conditions and the following disclaimer. +// +// 2. Redistributions in binary form must reproduce the above copyright notice, this list +// of conditions and the following disclaimer in the documentation and/or other +// materials provided with the distribution. +// +// 3. Neither the name of the copyright holder nor the names of its contributors may be +// used to endorse or promote products derived from this software without specific +// prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY +// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL +// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, +// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF +// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <string.h> +#include "misc_log_ex.h" +#include "wipeable_string.h" + +namespace epee +{ + +void *(*wipeable_string::wipefunc)(void*, size_t) = NULL; + +wipeable_string::wipeable_string(const wipeable_string &other): + buffer(other.buffer) +{ +} + +wipeable_string::wipeable_string(wipeable_string &&other) +{ + if (&other == this) + return; + buffer = std::move(other.buffer); +} + +wipeable_string::wipeable_string(const std::string &other) +{ + grow(other.size()); + memcpy(buffer.data(), other.c_str(), size()); +} + +wipeable_string::wipeable_string(std::string &&other) +{ + CHECK_AND_ASSERT_THROW_MES(wipefunc, "wipefunc is not set"); + grow(other.size()); + memcpy(buffer.data(), other.c_str(), size()); + if (!other.empty()) + { + wipefunc(&other[0], other.size()); // we're kinda left with this again aren't we + other = std::string(); + } +} + +wipeable_string::wipeable_string(const char *s) +{ + grow(strlen(s)); + memcpy(buffer.data(), s, size()); +} + +wipeable_string::~wipeable_string() +{ + wipe(); +} + +void wipeable_string::wipe() +{ + CHECK_AND_ASSERT_THROW_MES(wipefunc, "wipefunc is not set"); + wipefunc(buffer.data(), buffer.size() * sizeof(char)); +} + +void wipeable_string::grow(size_t sz, size_t reserved) +{ + CHECK_AND_ASSERT_THROW_MES(wipefunc, "wipefunc is not set"); + if (reserved < sz) + reserved = sz; + if (reserved <= buffer.capacity()) + { + if (sz < buffer.size()) + wipefunc(buffer.data() + sz, buffer.size() - sz); + buffer.resize(sz); + return; + } + size_t old_sz = buffer.size(); + std::unique_ptr<char[]> tmp{new char[old_sz]}; + memcpy(tmp.get(), buffer.data(), old_sz * sizeof(char)); + wipefunc(buffer.data(), old_sz * sizeof(char)); + buffer.reserve(reserved); + buffer.resize(sz); + memcpy(buffer.data(), tmp.get(), sz * sizeof(char)); + wipefunc(tmp.get(), old_sz * sizeof(char)); +} + +void wipeable_string::push_back(char c) +{ + grow(size() + 1); + buffer.back() = c; +} + +void wipeable_string::pop_back() +{ + resize(size() - 1); +} + +void wipeable_string::resize(size_t sz) +{ + grow(sz); +} + +void wipeable_string::reserve(size_t sz) +{ + grow(size(), sz); +} + +void wipeable_string::clear() +{ + resize(0); +} + +wipeable_string &wipeable_string::operator=(wipeable_string &&other) +{ + if (&other != this) + buffer = std::move(other.buffer); + return *this; +} + +wipeable_string &wipeable_string::operator=(const wipeable_string &other) +{ + if (&other != this) + buffer = other.buffer; + return *this; +} + +} |