ladybird/Libraries/LibCrypt/crypt.cpp
2020-07-28 17:07:22 +02:00

78 lines
2.7 KiB
C++

/*
* Copyright (c) 2020, Peter Elliott <pelliott@ualberta.ca>
* 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.
*
* 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 <AK/Base64.h>
#include <AK/Types.h>
#include <LibCrypto/Hash/SHA2.h>
#include <string.h>
#include <unistd.h>
extern "C" {
static struct crypt_data crypt_data;
char* crypt(const char* key, const char* salt)
{
crypt_data.initialized = true;
return crypt_r(key, salt, &crypt_data);
}
static constexpr size_t crypt_salt_max = 16;
static constexpr size_t sha_string_length = 44;
char* crypt_r(const char* key, const char* salt, struct crypt_data* data)
{
if (!data->initialized) {
errno = EINVAL;
return nullptr;
}
if (salt[0] == '$') {
if (salt[1] == '5') {
const char* salt_value = salt + 3;
size_t salt_len = min(strcspn(salt_value, "$"), crypt_salt_max);
size_t header_len = salt_len + 3;
strncpy(data->result, salt, header_len);
data->result[header_len] = '$';
Crypto::Hash::SHA256 sha;
sha.update(key);
sha.update((const u8*)salt_value, salt_len);
auto digest = sha.digest();
auto string = encode_base64(ReadonlyBytes(digest.immutable_data(), digest.data_length()));
strncpy(data->result + header_len + 1, string.characters(), sha_string_length);
return data->result;
}
}
// DES crypt is not available.
errno = EINVAL;
return nullptr;
}
}