crypto.c

 1// SPDX-License-Identifier: GPL-2.0
 2/* Multipath TCP cryptographic functions
 3 * Copyright (c) 2017 - 2019, Intel Corporation.
 4 *
 5 * Note: This code is based on mptcp_ctrl.c, mptcp_ipv4.c, and
 6 *       mptcp_ipv6 from multipath-tcp.org, authored by:
 7 *
 8 *       Sébastien Barré <sebastien.barre@uclouvain.be>
 9 *       Christoph Paasch <christoph.paasch@uclouvain.be>
10 *       Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
11 *       Gregory Detal <gregory.detal@uclouvain.be>
12 *       Fabien Duchêne <fabien.duchene@uclouvain.be>
13 *       Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
14 *       Lavkesh Lahngir <lavkesh51@gmail.com>
15 *       Andreas Ripke <ripke@neclab.eu>
16 *       Vlad Dogaru <vlad.dogaru@intel.com>
17 *       Octavian Purdila <octavian.purdila@intel.com>
18 *       John Ronan <jronan@tssg.org>
19 *       Catalin Nicutar <catalin.nicutar@gmail.com>
20 *       Brandon Heller <brandonh@stanford.edu>
21 */
22
23#include <linux/kernel.h>
24#include <crypto/sha2.h>
25
26#include "protocol.h"
27
28#define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / 4)
29
30void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn)
31{
32	__be32 mptcp_hashed_key[SHA256_DIGEST_WORDS];
33	__be64 input = cpu_to_be64(key);
34
35	sha256((__force u8 *)&input, sizeof(input), (u8 *)mptcp_hashed_key);
36
37	if (token)
38		*token = be32_to_cpu(mptcp_hashed_key[0]);
39	if (idsn)
40		*idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[6]));
41}
42
43void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac)
44{
45	__be64 key[2] = { cpu_to_be64(key1), cpu_to_be64(key2) };
46
47	hmac_sha256_usingrawkey((const u8 *)key, sizeof(key), msg, len, hmac);
48}
49
50#if IS_MODULE(CONFIG_MPTCP_KUNIT_TEST)
51EXPORT_SYMBOL_GPL(mptcp_crypto_hmac_sha);
52#endif