summaryrefslogtreecommitdiff
path: root/crypto/ecb.c
blob: cc7625d1a475e8d3db8aa8a1b733640b910a3a41 (plain) (blame)
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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * ECB: Electronic CodeBook mode
 *
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 */

#include <crypto/internal/cipher.h>
#include <crypto/internal/skcipher.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>

static int crypto_ecb_crypt(struct crypto_cipher *cipher, const u8 *src,
			    u8 *dst, unsigned nbytes, bool final,
			    void (*fn)(struct crypto_tfm *, u8 *, const u8 *))
{
	const unsigned int bsize = crypto_cipher_blocksize(cipher);

	while (nbytes >= bsize) {
		fn(crypto_cipher_tfm(cipher), dst, src);

		src += bsize;
		dst += bsize;

		nbytes -= bsize;
	}

	return nbytes && final ? -EINVAL : nbytes;
}

static int crypto_ecb_encrypt2(struct crypto_lskcipher *tfm, const u8 *src,
			       u8 *dst, unsigned len, u8 *iv, bool final)
{
	struct crypto_cipher **ctx = crypto_lskcipher_ctx(tfm);
	struct crypto_cipher *cipher = *ctx;

	return crypto_ecb_crypt(cipher, src, dst, len, final,
				crypto_cipher_alg(cipher)->cia_encrypt);
}

static int crypto_ecb_decrypt2(struct crypto_lskcipher *tfm, const u8 *src,
			       u8 *dst, unsigned len, u8 *iv, bool final)
{
	struct crypto_cipher **ctx = crypto_lskcipher_ctx(tfm);
	struct crypto_cipher *cipher = *ctx;

	return crypto_ecb_crypt(cipher, src, dst, len, final,
				crypto_cipher_alg(cipher)->cia_decrypt);
}

static int lskcipher_setkey_simple2(struct crypto_lskcipher *tfm,
				    const u8 *key, unsigned int keylen)
{
	struct crypto_cipher **ctx = crypto_lskcipher_ctx(tfm);
	struct crypto_cipher *cipher = *ctx;

	crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK);
	crypto_cipher_set_flags(cipher, crypto_lskcipher_get_flags(tfm) &
				CRYPTO_TFM_REQ_MASK);
	return crypto_cipher_setkey(cipher, key, keylen);
}

static int lskcipher_init_tfm_simple2(struct crypto_lskcipher *tfm)
{
	struct lskcipher_instance *inst = lskcipher_alg_instance(tfm);
	struct crypto_cipher **ctx = crypto_lskcipher_ctx(tfm);
	struct crypto_cipher_spawn *spawn;
	struct crypto_cipher *cipher;

	spawn = lskcipher_instance_ctx(inst);
	cipher = crypto_spawn_cipher(spawn);
	if (IS_ERR(cipher))
		return PTR_ERR(cipher);

	*ctx = cipher;
	return 0;
}

static void lskcipher_exit_tfm_simple2(struct crypto_lskcipher *tfm)
{
	struct crypto_cipher **ctx = crypto_lskcipher_ctx(tfm);

	crypto_free_cipher(*ctx);
}

static void lskcipher_free_instance_simple2(struct lskcipher_instance *inst)
{
	crypto_drop_cipher(lskcipher_instance_ctx(inst));
	kfree(inst);
}

static struct lskcipher_instance *lskcipher_alloc_instance_simple2(
	struct crypto_template *tmpl, struct rtattr **tb)
{
	struct crypto_cipher_spawn *spawn;
	struct lskcipher_instance *inst;
	struct crypto_alg *cipher_alg;
	u32 mask;
	int err;

	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_LSKCIPHER, &mask);
	if (err)
		return ERR_PTR(err);

	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
	if (!inst)
		return ERR_PTR(-ENOMEM);
	spawn = lskcipher_instance_ctx(inst);

	err = crypto_grab_cipher(spawn, lskcipher_crypto_instance(inst),
				 crypto_attr_alg_name(tb[1]), 0, mask);
	if (err)
		goto err_free_inst;
	cipher_alg = crypto_spawn_cipher_alg(spawn);

	err = crypto_inst_setname(lskcipher_crypto_instance(inst), tmpl->name,
				  cipher_alg);
	if (err)
		goto err_free_inst;

	inst->free = lskcipher_free_instance_simple2;

	/* Default algorithm properties, can be overridden */
	inst->alg.co.base.cra_blocksize = cipher_alg->cra_blocksize;
	inst->alg.co.base.cra_alignmask = cipher_alg->cra_alignmask;
	inst->alg.co.base.cra_priority = cipher_alg->cra_priority;
	inst->alg.co.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
	inst->alg.co.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
	inst->alg.co.ivsize = cipher_alg->cra_blocksize;

	/* Use struct crypto_cipher * by default, can be overridden */
	inst->alg.co.base.cra_ctxsize = sizeof(struct crypto_cipher *);
	inst->alg.setkey = lskcipher_setkey_simple2;
	inst->alg.init = lskcipher_init_tfm_simple2;
	inst->alg.exit = lskcipher_exit_tfm_simple2;

	return inst;

err_free_inst:
	lskcipher_free_instance_simple2(inst);
	return ERR_PTR(err);
}

static int crypto_ecb_create2(struct crypto_template *tmpl, struct rtattr **tb)
{
	struct lskcipher_instance *inst;
	int err;

	inst = lskcipher_alloc_instance_simple2(tmpl, tb);
	if (IS_ERR(inst))
		return PTR_ERR(inst);

	/* ECB mode doesn't take an IV */
	inst->alg.co.ivsize = 0;

	inst->alg.encrypt = crypto_ecb_encrypt2;
	inst->alg.decrypt = crypto_ecb_decrypt2;

	err = lskcipher_register_instance(tmpl, inst);
	if (err)
		inst->free(inst);

	return err;
}

static int crypto_ecb_create(struct crypto_template *tmpl, struct rtattr **tb)
{
	struct crypto_lskcipher_spawn *spawn;
	struct lskcipher_alg *cipher_alg;
	struct lskcipher_instance *inst;
	int err;

	inst = lskcipher_alloc_instance_simple(tmpl, tb);
	if (IS_ERR(inst)) {
		err = crypto_ecb_create2(tmpl, tb);
		return err;
	}

	spawn = lskcipher_instance_ctx(inst);
	cipher_alg = crypto_lskcipher_spawn_alg(spawn);

	/* ECB mode doesn't take an IV */
	inst->alg.co.ivsize = 0;
	if (cipher_alg->co.ivsize)
		return -EINVAL;

	inst->alg.co.base.cra_ctxsize = cipher_alg->co.base.cra_ctxsize;
	inst->alg.setkey = cipher_alg->setkey;
	inst->alg.encrypt = cipher_alg->encrypt;
	inst->alg.decrypt = cipher_alg->decrypt;
	inst->alg.init = cipher_alg->init;
	inst->alg.exit = cipher_alg->exit;

	err = lskcipher_register_instance(tmpl, inst);
	if (err)
		inst->free(inst);

	return err;
}

static struct crypto_template crypto_ecb_tmpl = {
	.name = "ecb",
	.create = crypto_ecb_create,
	.module = THIS_MODULE,
};

static int __init crypto_ecb_module_init(void)
{
	return crypto_register_template(&crypto_ecb_tmpl);
}

static void __exit crypto_ecb_module_exit(void)
{
	crypto_unregister_template(&crypto_ecb_tmpl);
}

subsys_initcall(crypto_ecb_module_init);
module_exit(crypto_ecb_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ECB block cipher mode of operation");
MODULE_ALIAS_CRYPTO("ecb");
MODULE_IMPORT_NS(CRYPTO_INTERNAL);