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 | #include <asm/unaligned.h> |
26 | |
27 | #include "protocol.h" |
28 | |
29 | #define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / 4) |
30 | |
31 | void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn) |
32 | { |
33 | __be32 mptcp_hashed_key[SHA256_DIGEST_WORDS]; |
34 | __be64 input = cpu_to_be64(key); |
35 | |
36 | sha256(data: (__force u8 *)&input, len: sizeof(input), out: (u8 *)mptcp_hashed_key); |
37 | |
38 | if (token) |
39 | *token = be32_to_cpu(mptcp_hashed_key[0]); |
40 | if (idsn) |
41 | *idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[6])); |
42 | } |
43 | |
44 | void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac) |
45 | { |
46 | u8 input[SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE]; |
47 | u8 key1be[8]; |
48 | u8 key2be[8]; |
49 | int i; |
50 | |
51 | if (WARN_ON_ONCE(len > SHA256_DIGEST_SIZE)) |
52 | len = SHA256_DIGEST_SIZE; |
53 | |
54 | put_unaligned_be64(val: key1, p: key1be); |
55 | put_unaligned_be64(val: key2, p: key2be); |
56 | |
57 | /* Generate key xored with ipad */ |
58 | memset(input, 0x36, SHA256_BLOCK_SIZE); |
59 | for (i = 0; i < 8; i++) |
60 | input[i] ^= key1be[i]; |
61 | for (i = 0; i < 8; i++) |
62 | input[i + 8] ^= key2be[i]; |
63 | |
64 | memcpy(&input[SHA256_BLOCK_SIZE], msg, len); |
65 | |
66 | /* emit sha256(K1 || msg) on the second input block, so we can |
67 | * reuse 'input' for the last hashing |
68 | */ |
69 | sha256(data: input, SHA256_BLOCK_SIZE + len, out: &input[SHA256_BLOCK_SIZE]); |
70 | |
71 | /* Prepare second part of hmac */ |
72 | memset(input, 0x5C, SHA256_BLOCK_SIZE); |
73 | for (i = 0; i < 8; i++) |
74 | input[i] ^= key1be[i]; |
75 | for (i = 0; i < 8; i++) |
76 | input[i + 8] ^= key2be[i]; |
77 | |
78 | sha256(data: input, SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE, out: hmac); |
79 | } |
80 | |
81 | #if IS_MODULE(CONFIG_MPTCP_KUNIT_TEST) |
82 | EXPORT_SYMBOL_GPL(mptcp_crypto_hmac_sha); |
83 | #endif |
84 | |