aes_gcm.c
2.44 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
/*
* Copyright 2014-2015, Qualcomm Atheros, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/err.h>
#include <crypto/aead.h>
#include <net/mac80211.h>
#include "key.h"
#include "aes_gcm.h"
void ieee80211_aes_gcm_encrypt(struct crypto_aead *tfm, u8 *j_0, u8 *aad,
u8 *data, size_t data_len, u8 *mic)
{
struct scatterlist sg[3];
char aead_req_data[sizeof(struct aead_request) +
crypto_aead_reqsize(tfm)]
__aligned(__alignof__(struct aead_request));
struct aead_request *aead_req = (void *)aead_req_data;
memset(aead_req, 0, sizeof(aead_req_data));
sg_init_table(sg, 3);
sg_set_buf(&sg[0], &aad[2], be16_to_cpup((__be16 *)aad));
sg_set_buf(&sg[1], data, data_len);
sg_set_buf(&sg[2], mic, IEEE80211_GCMP_MIC_LEN);
aead_request_set_tfm(aead_req, tfm);
aead_request_set_crypt(aead_req, sg, sg, data_len, j_0);
aead_request_set_ad(aead_req, sg[0].length);
crypto_aead_encrypt(aead_req);
}
int ieee80211_aes_gcm_decrypt(struct crypto_aead *tfm, u8 *j_0, u8 *aad,
u8 *data, size_t data_len, u8 *mic)
{
struct scatterlist sg[3];
char aead_req_data[sizeof(struct aead_request) +
crypto_aead_reqsize(tfm)]
__aligned(__alignof__(struct aead_request));
struct aead_request *aead_req = (void *)aead_req_data;
if (data_len == 0)
return -EINVAL;
memset(aead_req, 0, sizeof(aead_req_data));
sg_init_table(sg, 3);
sg_set_buf(&sg[0], &aad[2], be16_to_cpup((__be16 *)aad));
sg_set_buf(&sg[1], data, data_len);
sg_set_buf(&sg[2], mic, IEEE80211_GCMP_MIC_LEN);
aead_request_set_tfm(aead_req, tfm);
aead_request_set_crypt(aead_req, sg, sg,
data_len + IEEE80211_GCMP_MIC_LEN, j_0);
aead_request_set_ad(aead_req, sg[0].length);
return crypto_aead_decrypt(aead_req);
}
struct crypto_aead *ieee80211_aes_gcm_key_setup_encrypt(const u8 key[],
size_t key_len)
{
struct crypto_aead *tfm;
int err;
tfm = crypto_alloc_aead("gcm(aes)", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm))
return tfm;
err = crypto_aead_setkey(tfm, key, key_len);
if (err)
goto free_aead;
err = crypto_aead_setauthsize(tfm, IEEE80211_GCMP_MIC_LEN);
if (err)
goto free_aead;
return tfm;
free_aead:
crypto_free_aead(tfm);
return ERR_PTR(err);
}
void ieee80211_aes_gcm_key_free(struct crypto_aead *tfm)
{
crypto_free_aead(tfm);
}