From e3e3cba99c06d1ee56200800fce727f8c5dd4d41 Mon Sep 17 00:00:00 2001 From: Alberto Sartori Date: Wed, 15 Nov 2023 16:07:10 +0100 Subject: utils/cpp: add IsAHash function This function is mainly used to check that the hash of a Digest received over the wire is a real hash, to prevent a malicious attack. --- src/utils/cpp/verify_hash.hpp | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 src/utils/cpp/verify_hash.hpp (limited to 'src/utils/cpp/verify_hash.hpp') diff --git a/src/utils/cpp/verify_hash.hpp b/src/utils/cpp/verify_hash.hpp new file mode 100644 index 00000000..ab2a4b45 --- /dev/null +++ b/src/utils/cpp/verify_hash.hpp @@ -0,0 +1,35 @@ +// Copyright 2023 Huawei Cloud Computing Technology Co., Ltd. +// +// 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. + +#ifndef INCLUDED_SRC_UTILS_CPP_VERIFY_HASH_HPP +#define INCLUDED_SRC_UTILS_CPP_VERIFY_HASH_HPP +#include +#include +#include +#include + +#include +/// \brief Check if the passed string \p s is a hash. +/// This function is mainly used to check that the hash of a Digest received +/// over the wire is a real hash, to prevent a malicious attack. +[[nodiscard]] static inline auto IsAHash(std::string const& s) noexcept + -> std::optional { + if (!std::all_of(s.begin(), s.end(), [](unsigned char c) { + return std::isxdigit(c); + })) { + return fmt::format("Invalid hash {}", s); + } + return std::nullopt; +} +#endif -- cgit v1.2.3