ClickHouse/src/Functions/FunctionsAES.cpp
2020-10-14 16:33:07 +03:00

64 lines
1.7 KiB
C++

#include <Functions/FunctionsAES.h>
#if USE_SSL
#include <openssl/evp.h>
#include <openssl/err.h>
#include <string>
#include <cassert>
namespace DB
{
namespace ErrorCodes
{
extern const int OPENSSL_ERROR;
}
}
namespace OpenSSLDetails
{
void onError(std::string error_message)
{
error_message += ". OpenSSL error code: " + std::to_string(ERR_get_error());
throw DB::Exception(error_message, DB::ErrorCodes::OPENSSL_ERROR);
}
StringRef foldEncryptionKeyInMySQLCompatitableMode(size_t cipher_key_size, const StringRef & key, std::array<char, EVP_MAX_KEY_LENGTH> & folded_key)
{
assert(cipher_key_size <= EVP_MAX_KEY_LENGTH);
memcpy(folded_key.data(), key.data, cipher_key_size);
for (size_t i = cipher_key_size; i < key.size; ++i)
{
folded_key[i % cipher_key_size] ^= key.data[i];
}
return StringRef(folded_key.data(), cipher_key_size);
}
const EVP_CIPHER * getCipherByName(const StringRef & cipher_name)
{
const auto * evp_cipher = EVP_get_cipherbyname(cipher_name.data);
if (evp_cipher == nullptr)
{
// For some reasons following ciphers can't be found by name.
if (cipher_name == "aes-128-cfb128")
evp_cipher = EVP_aes_128_cfb128();
else if (cipher_name == "aes-192-cfb128")
evp_cipher = EVP_aes_192_cfb128();
else if (cipher_name == "aes-256-cfb128")
evp_cipher = EVP_aes_256_cfb128();
}
// NOTE: cipher obtained not via EVP_CIPHER_fetch() would cause extra work on each context reset
// with EVP_CIPHER_CTX_reset() or EVP_EncryptInit_ex(), but using EVP_CIPHER_fetch()
// causes data race, so we stick to the slower but safer alternative here.
return evp_cipher;
}
}
#endif