1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /* Multipath TCP cryptographic functions
3*4882a593Smuzhiyun * Copyright (c) 2017 - 2019, Intel Corporation.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Note: This code is based on mptcp_ctrl.c, mptcp_ipv4.c, and
6*4882a593Smuzhiyun * mptcp_ipv6 from multipath-tcp.org, authored by:
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun * Sébastien Barré <sebastien.barre@uclouvain.be>
9*4882a593Smuzhiyun * Christoph Paasch <christoph.paasch@uclouvain.be>
10*4882a593Smuzhiyun * Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
11*4882a593Smuzhiyun * Gregory Detal <gregory.detal@uclouvain.be>
12*4882a593Smuzhiyun * Fabien Duchêne <fabien.duchene@uclouvain.be>
13*4882a593Smuzhiyun * Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
14*4882a593Smuzhiyun * Lavkesh Lahngir <lavkesh51@gmail.com>
15*4882a593Smuzhiyun * Andreas Ripke <ripke@neclab.eu>
16*4882a593Smuzhiyun * Vlad Dogaru <vlad.dogaru@intel.com>
17*4882a593Smuzhiyun * Octavian Purdila <octavian.purdila@intel.com>
18*4882a593Smuzhiyun * John Ronan <jronan@tssg.org>
19*4882a593Smuzhiyun * Catalin Nicutar <catalin.nicutar@gmail.com>
20*4882a593Smuzhiyun * Brandon Heller <brandonh@stanford.edu>
21*4882a593Smuzhiyun */
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun #include <linux/kernel.h>
24*4882a593Smuzhiyun #include <crypto/sha.h>
25*4882a593Smuzhiyun #include <asm/unaligned.h>
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun #include "protocol.h"
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun #define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / 4)
30*4882a593Smuzhiyun
mptcp_crypto_key_sha(u64 key,u32 * token,u64 * idsn)31*4882a593Smuzhiyun void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun __be32 mptcp_hashed_key[SHA256_DIGEST_WORDS];
34*4882a593Smuzhiyun __be64 input = cpu_to_be64(key);
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun sha256((__force u8 *)&input, sizeof(input), (u8 *)mptcp_hashed_key);
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun if (token)
39*4882a593Smuzhiyun *token = be32_to_cpu(mptcp_hashed_key[0]);
40*4882a593Smuzhiyun if (idsn)
41*4882a593Smuzhiyun *idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[6]));
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun
mptcp_crypto_hmac_sha(u64 key1,u64 key2,u8 * msg,int len,void * hmac)44*4882a593Smuzhiyun void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun u8 input[SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE];
47*4882a593Smuzhiyun u8 key1be[8];
48*4882a593Smuzhiyun u8 key2be[8];
49*4882a593Smuzhiyun int i;
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun if (WARN_ON_ONCE(len > SHA256_DIGEST_SIZE))
52*4882a593Smuzhiyun len = SHA256_DIGEST_SIZE;
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun put_unaligned_be64(key1, key1be);
55*4882a593Smuzhiyun put_unaligned_be64(key2, key2be);
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun /* Generate key xored with ipad */
58*4882a593Smuzhiyun memset(input, 0x36, SHA256_BLOCK_SIZE);
59*4882a593Smuzhiyun for (i = 0; i < 8; i++)
60*4882a593Smuzhiyun input[i] ^= key1be[i];
61*4882a593Smuzhiyun for (i = 0; i < 8; i++)
62*4882a593Smuzhiyun input[i + 8] ^= key2be[i];
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun memcpy(&input[SHA256_BLOCK_SIZE], msg, len);
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun /* emit sha256(K1 || msg) on the second input block, so we can
67*4882a593Smuzhiyun * reuse 'input' for the last hashing
68*4882a593Smuzhiyun */
69*4882a593Smuzhiyun sha256(input, SHA256_BLOCK_SIZE + len, &input[SHA256_BLOCK_SIZE]);
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun /* Prepare second part of hmac */
72*4882a593Smuzhiyun memset(input, 0x5C, SHA256_BLOCK_SIZE);
73*4882a593Smuzhiyun for (i = 0; i < 8; i++)
74*4882a593Smuzhiyun input[i] ^= key1be[i];
75*4882a593Smuzhiyun for (i = 0; i < 8; i++)
76*4882a593Smuzhiyun input[i + 8] ^= key2be[i];
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun sha256(input, SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE, hmac);
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun #if IS_MODULE(CONFIG_MPTCP_KUNIT_TESTS)
82*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(mptcp_crypto_hmac_sha);
83*4882a593Smuzhiyun #endif
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