root/net/mptcp/crypto.c
// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP cryptographic functions
 * Copyright (c) 2017 - 2019, Intel Corporation.
 *
 * Note: This code is based on mptcp_ctrl.c, mptcp_ipv4.c, and
 *       mptcp_ipv6 from multipath-tcp.org, authored by:
 *
 *       Sébastien Barré <sebastien.barre@uclouvain.be>
 *       Christoph Paasch <christoph.paasch@uclouvain.be>
 *       Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
 *       Gregory Detal <gregory.detal@uclouvain.be>
 *       Fabien Duchêne <fabien.duchene@uclouvain.be>
 *       Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
 *       Lavkesh Lahngir <lavkesh51@gmail.com>
 *       Andreas Ripke <ripke@neclab.eu>
 *       Vlad Dogaru <vlad.dogaru@intel.com>
 *       Octavian Purdila <octavian.purdila@intel.com>
 *       John Ronan <jronan@tssg.org>
 *       Catalin Nicutar <catalin.nicutar@gmail.com>
 *       Brandon Heller <brandonh@stanford.edu>
 */

#include <linux/kernel.h>
#include <crypto/sha2.h>

#include "protocol.h"

#define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / 4)

void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn)
{
        __be32 mptcp_hashed_key[SHA256_DIGEST_WORDS];
        __be64 input = cpu_to_be64(key);

        sha256((__force u8 *)&input, sizeof(input), (u8 *)mptcp_hashed_key);

        if (token)
                *token = be32_to_cpu(mptcp_hashed_key[0]);
        if (idsn)
                *idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[6]));
}

void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac)
{
        __be64 key[2] = { cpu_to_be64(key1), cpu_to_be64(key2) };

        hmac_sha256_usingrawkey((const u8 *)key, sizeof(key), msg, len, hmac);
}

#if IS_MODULE(CONFIG_MPTCP_KUNIT_TEST)
EXPORT_SYMBOL_GPL(mptcp_crypto_hmac_sha);
#endif