1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2003-2004, Instant802 Networks, Inc.
4 * Copyright 2005-2006, Devicescape Software, Inc.
5 * Copyright 2014-2015, Qualcomm Atheros, Inc.
6 *
7 * Rewrite: Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org>
8 */
9
10#include <linux/kernel.h>
11#include <linux/types.h>
12#include <linux/err.h>
13#include <linux/scatterlist.h>
14#include <crypto/aead.h>
15
16#include "aead_api.h"
17
18int aead_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
19		 u8 *data, size_t data_len, u8 *mic)
20{
21	size_t mic_len = crypto_aead_authsize(tfm);
22	struct scatterlist sg[3];
23	struct aead_request *aead_req;
24	int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
25	u8 *__aad;
26	int ret;
27
28	aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
29	if (!aead_req)
30		return -ENOMEM;
31
32	__aad = (u8 *)aead_req + reqsize;
33	memcpy(__aad, aad, aad_len);
34
35	sg_init_table(sg, 3);
36	sg_set_buf(&sg[0], __aad, aad_len);
37	sg_set_buf(&sg[1], data, data_len);
38	sg_set_buf(&sg[2], mic, mic_len);
39
40	aead_request_set_tfm(aead_req, tfm);
41	aead_request_set_crypt(aead_req, sg, sg, data_len, b_0);
42	aead_request_set_ad(aead_req, sg[0].length);
43
44	ret = crypto_aead_encrypt(aead_req);
45	kfree_sensitive(aead_req);
46
47	return ret;
48}
49
50int aead_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
51		 u8 *data, size_t data_len, u8 *mic)
52{
53	size_t mic_len = crypto_aead_authsize(tfm);
54	struct scatterlist sg[3];
55	struct aead_request *aead_req;
56	int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
57	u8 *__aad;
58	int err;
59
60	if (data_len == 0)
61		return -EINVAL;
62
63	aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
64	if (!aead_req)
65		return -ENOMEM;
66
67	__aad = (u8 *)aead_req + reqsize;
68	memcpy(__aad, aad, aad_len);
69
70	sg_init_table(sg, 3);
71	sg_set_buf(&sg[0], __aad, aad_len);
72	sg_set_buf(&sg[1], data, data_len);
73	sg_set_buf(&sg[2], mic, mic_len);
74
75	aead_request_set_tfm(aead_req, tfm);
76	aead_request_set_crypt(aead_req, sg, sg, data_len + mic_len, b_0);
77	aead_request_set_ad(aead_req, sg[0].length);
78
79	err = crypto_aead_decrypt(aead_req);
80	kfree_sensitive(aead_req);
81
82	return err;
83}
84
85struct crypto_aead *
86aead_key_setup_encrypt(const char *alg, const u8 key[],
87		       size_t key_len, size_t mic_len)
88{
89	struct crypto_aead *tfm;
90	int err;
91
92	tfm = crypto_alloc_aead(alg, 0, CRYPTO_ALG_ASYNC);
93	if (IS_ERR(tfm))
94		return tfm;
95
96	err = crypto_aead_setkey(tfm, key, key_len);
97	if (err)
98		goto free_aead;
99	err = crypto_aead_setauthsize(tfm, mic_len);
100	if (err)
101		goto free_aead;
102
103	return tfm;
104
105free_aead:
106	crypto_free_aead(tfm);
107	return ERR_PTR(err);
108}
109
110void aead_key_free(struct crypto_aead *tfm)
111{
112	crypto_free_aead(tfm);
113}
114