summaryrefslogtreecommitdiff
path: root/arch/s390/crypto/aes_s390.c
blob: 7a1033d8e00fe202ed15245b610f1455baf53f61 (plain)
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
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
/*
 * Cryptographic API.
 *
 * s390 implementation of the AES Cipher Algorithm.
 *
 * s390 Version:
 *   Copyright (C) 2005 IBM Deutschland GmbH, IBM Corporation
 *   Author(s): Jan Glauber (jang@de.ibm.com)
 *
 * Derived from "crypto/aes.c"
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/crypto.h>
#include "crypt_s390.h"

#define AES_MIN_KEY_SIZE	16
#define AES_MAX_KEY_SIZE	32

/* data block size for all key lengths */
#define AES_BLOCK_SIZE		16

int has_aes_128 = 0;
int has_aes_192 = 0;
int has_aes_256 = 0;

struct s390_aes_ctx {
	u8 iv[AES_BLOCK_SIZE];
	u8 key[AES_MAX_KEY_SIZE];
	int key_len;
};

static int aes_set_key(void *ctx, const u8 *in_key, unsigned int key_len,
		       u32 *flags)
{
	struct s390_aes_ctx *sctx = ctx;

	switch (key_len) {
	case 16:
		if (!has_aes_128)
			goto fail;
		break;
	case 24:
		if (!has_aes_192)
			goto fail;

		break;
	case 32:
		if (!has_aes_256)
			goto fail;
		break;
	default:
		/* invalid key length */
		goto fail;
		break;
	}

	sctx->key_len = key_len;
	memcpy(sctx->key, in_key, key_len);
	return 0;
fail:
	*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
	return -EINVAL;
}

static void aes_encrypt(void *ctx, u8 *out, const u8 *in)
{
	const struct s390_aes_ctx *sctx = ctx;

	switch (sctx->key_len) {
	case 16:
		crypt_s390_km(KM_AES_128_ENCRYPT, &sctx->key, out, in,
			      AES_BLOCK_SIZE);
		break;
	case 24:
		crypt_s390_km(KM_AES_192_ENCRYPT, &sctx->key, out, in,
			      AES_BLOCK_SIZE);
		break;
	case 32:
		crypt_s390_km(KM_AES_256_ENCRYPT, &sctx->key, out, in,
			      AES_BLOCK_SIZE);
		break;
	}
}

static void aes_decrypt(void *ctx, u8 *out, const u8 *in)
{
	const struct s390_aes_ctx *sctx = ctx;

	switch (sctx->key_len) {
	case 16:
		crypt_s390_km(KM_AES_128_DECRYPT, &sctx->key, out, in,
			      AES_BLOCK_SIZE);
		break;
	case 24:
		crypt_s390_km(KM_AES_192_DECRYPT, &sctx->key, out, in,
			      AES_BLOCK_SIZE);
		break;
	case 32:
		crypt_s390_km(KM_AES_256_DECRYPT, &sctx->key, out, in,
			      AES_BLOCK_SIZE);
		break;
	}
}

static unsigned int aes_encrypt_ecb(const struct cipher_desc *desc, u8 *out,
				    const u8 *in, unsigned int nbytes)
{
	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);

	switch (sctx->key_len) {
	case 16:
		crypt_s390_km(KM_AES_128_ENCRYPT, &sctx->key, out, in, nbytes);
		break;
	case 24:
		crypt_s390_km(KM_AES_192_ENCRYPT, &sctx->key, out, in, nbytes);
		break;
	case 32:
		crypt_s390_km(KM_AES_256_ENCRYPT, &sctx->key, out, in, nbytes);
		break;
	}
	return nbytes & ~(AES_BLOCK_SIZE - 1);
}

static unsigned int aes_decrypt_ecb(const struct cipher_desc *desc, u8 *out,
				    const u8 *in, unsigned int nbytes)
{
	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);

	switch (sctx->key_len) {
	case 16:
		crypt_s390_km(KM_AES_128_DECRYPT, &sctx->key, out, in, nbytes);
		break;
	case 24:
		crypt_s390_km(KM_AES_192_DECRYPT, &sctx->key, out, in, nbytes);
		break;
	case 32:
		crypt_s390_km(KM_AES_256_DECRYPT, &sctx->key, out, in, nbytes);
		break;
	}
	return nbytes & ~(AES_BLOCK_SIZE - 1);
}

static unsigned int aes_encrypt_cbc(const struct cipher_desc *desc, u8 *out,
				    const u8 *in, unsigned int nbytes)
{
	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);

	memcpy(&sctx->iv, desc->info, AES_BLOCK_SIZE);
	switch (sctx->key_len) {
	case 16:
		crypt_s390_kmc(KMC_AES_128_ENCRYPT, &sctx->iv, out, in, nbytes);
		break;
	case 24:
		crypt_s390_kmc(KMC_AES_192_ENCRYPT, &sctx->iv, out, in, nbytes);
		break;
	case 32:
		crypt_s390_kmc(KMC_AES_256_ENCRYPT, &sctx->iv, out, in, nbytes);
		break;
	}
	memcpy(desc->info, &sctx->iv, AES_BLOCK_SIZE);

	return nbytes & ~(AES_BLOCK_SIZE - 1);
}

static unsigned int aes_decrypt_cbc(const struct cipher_desc *desc, u8 *out,
				    const u8 *in, unsigned int nbytes)
{
	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);

	memcpy(&sctx->iv, desc->info, AES_BLOCK_SIZE);
	switch (sctx->key_len) {
	case 16:
		crypt_s390_kmc(KMC_AES_128_DECRYPT, &sctx->iv, out, in, nbytes);
		break;
	case 24:
		crypt_s390_kmc(KMC_AES_192_DECRYPT, &sctx->iv, out, in, nbytes);
		break;
	case 32:
		crypt_s390_kmc(KMC_AES_256_DECRYPT, &sctx->iv, out, in, nbytes);
		break;
	}
	return nbytes & ~(AES_BLOCK_SIZE - 1);
}


static struct crypto_alg aes_alg = {
	.cra_name		=	"aes",
	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		=	AES_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof(struct s390_aes_ctx),
	.cra_module		=	THIS_MODULE,
	.cra_list		=	LIST_HEAD_INIT(aes_alg.cra_list),
	.cra_u			=	{
		.cipher = {
			.cia_min_keysize	=	AES_MIN_KEY_SIZE,
			.cia_max_keysize	=	AES_MAX_KEY_SIZE,
			.cia_setkey		=	aes_set_key,
			.cia_encrypt		=	aes_encrypt,
			.cia_decrypt		=	aes_decrypt,
			.cia_encrypt_ecb	=	aes_encrypt_ecb,
			.cia_decrypt_ecb	=	aes_decrypt_ecb,
			.cia_encrypt_cbc	=	aes_encrypt_cbc,
			.cia_decrypt_cbc	=	aes_decrypt_cbc,
		}
	}
};

static int __init aes_init(void)
{
	int ret;

	if (crypt_s390_func_available(KM_AES_128_ENCRYPT))
		has_aes_128 = 1;
	if (crypt_s390_func_available(KM_AES_192_ENCRYPT))
		has_aes_192 = 1;
	if (crypt_s390_func_available(KM_AES_256_ENCRYPT))
		has_aes_256 = 1;

	if (!has_aes_128 && !has_aes_192 && !has_aes_256)
		return -ENOSYS;

	ret = crypto_register_alg(&aes_alg);
	if (ret != 0)
		printk(KERN_INFO "crypt_s390: aes_s390 couldn't be loaded.\n");
	return ret;
}

static void __exit aes_fini(void)
{
	crypto_unregister_alg(&aes_alg);
}

module_init(aes_init);
module_exit(aes_fini);

MODULE_ALIAS("aes");

MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm");
MODULE_LICENSE("GPL");