summaryrefslogtreecommitdiffstats
path: root/crypto/akcipher.c
blob: e0ff5f4dda6d62c40d6478b5c727713d1d8ebc6a (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
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Public Key Encryption
 *
 * Copyright (c) 2015, Intel Corporation
 * Authors: Tadeusz Struk <tadeusz.struk@intel.com>
 */
#include <crypto/internal/akcipher.h>
#include <linux/cryptouser.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <net/netlink.h>

#include "internal.h"

#define CRYPTO_ALG_TYPE_AHASH_MASK	0x0000000e

static int __maybe_unused crypto_akcipher_report(
	struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_akcipher rakcipher;

	memset(&rakcipher, 0, sizeof(rakcipher));

	strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));

	return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
		       sizeof(rakcipher), &rakcipher);
}

static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
	__maybe_unused;

static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
	seq_puts(m, "type         : akcipher\n");
}

static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
{
	struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
	struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);

	alg->exit(akcipher);
}

static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
{
	struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
	struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);

	if (alg->exit)
		akcipher->base.exit = crypto_akcipher_exit_tfm;

	if (alg->init)
		return alg->init(akcipher);

	return 0;
}

static void crypto_akcipher_free_instance(struct crypto_instance *inst)
{
	struct akcipher_instance *akcipher = akcipher_instance(inst);

	akcipher->free(akcipher);
}

static const struct crypto_type crypto_akcipher_type = {
	.extsize = crypto_alg_extsize,
	.init_tfm = crypto_akcipher_init_tfm,
	.free = crypto_akcipher_free_instance,
#ifdef CONFIG_PROC_FS
	.show = crypto_akcipher_show,
#endif
#if IS_ENABLED(CONFIG_CRYPTO_USER)
	.report = crypto_akcipher_report,
#endif
	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	.type = CRYPTO_ALG_TYPE_AKCIPHER,
	.tfmsize = offsetof(struct crypto_akcipher, base),
};

int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
			 struct crypto_instance *inst,
			 const char *name, u32 type, u32 mask)
{
	spawn->base.frontend = &crypto_akcipher_type;
	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_grab_akcipher);

struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
					      u32 mask)
{
	return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);

static void akcipher_prepare_alg(struct akcipher_alg *alg)
{
	struct crypto_alg *base = &alg->base;

	base->cra_type = &crypto_akcipher_type;
	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
}

static int akcipher_default_op(struct akcipher_request *req)
{
	return -ENOSYS;
}

static int akcipher_default_set_key(struct crypto_akcipher *tfm,
				     const void *key, unsigned int keylen)
{
	return -ENOSYS;
}

int crypto_register_akcipher(struct akcipher_alg *alg)
{
	struct crypto_alg *base = &alg->base;

	if (!alg->sign)
		alg->sign = akcipher_default_op;
	if (!alg->verify)
		alg->verify = akcipher_default_op;
	if (!alg->encrypt)
		alg->encrypt = akcipher_default_op;
	if (!alg->decrypt)
		alg->decrypt = akcipher_default_op;
	if (!alg->set_priv_key)
		alg->set_priv_key = akcipher_default_set_key;

	akcipher_prepare_alg(alg);
	return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_akcipher);

void crypto_unregister_akcipher(struct akcipher_alg *alg)
{
	crypto_unregister_alg(&alg->base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);

int akcipher_register_instance(struct crypto_template *tmpl,
			       struct akcipher_instance *inst)
{
	if (WARN_ON(!inst->free))
		return -EINVAL;
	akcipher_prepare_alg(&inst->alg);
	return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
}
EXPORT_SYMBOL_GPL(akcipher_register_instance);

int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
{
	unsigned int reqsize = crypto_akcipher_reqsize(data->tfm);
	struct akcipher_request *req;
	struct scatterlist *sg;
	unsigned int mlen;
	unsigned int len;
	u8 *buf;

	if (data->dst)
		mlen = max(data->slen, data->dlen);
	else
		mlen = data->slen + data->dlen;

	len = sizeof(*req) + reqsize + mlen;
	if (len < mlen)
		return -EOVERFLOW;

	req = kzalloc(len, GFP_KERNEL);
	if (!req)
		return -ENOMEM;

	data->req = req;
	akcipher_request_set_tfm(req, data->tfm);

	buf = (u8 *)(req + 1) + reqsize;
	data->buf = buf;
	memcpy(buf, data->src, data->slen);

	sg = &data->sg;
	sg_init_one(sg, buf, mlen);
	akcipher_request_set_crypt(req, sg, data->dst ? sg : NULL,
				   data->slen, data->dlen);

	crypto_init_wait(&data->cwait);
	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
				      crypto_req_done, &data->cwait);

	return 0;
}
EXPORT_SYMBOL_GPL(crypto_akcipher_sync_prep);

int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data, int err)
{
	err = crypto_wait_req(err, &data->cwait);
	if (data->dst)
		memcpy(data->dst, data->buf, data->dlen);
	data->dlen = data->req->dst_len;
	kfree_sensitive(data->req);
	return err;
}
EXPORT_SYMBOL_GPL(crypto_akcipher_sync_post);

int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
				 const void *src, unsigned int slen,
				 void *dst, unsigned int dlen)
{
	struct crypto_akcipher_sync_data data = {
		.tfm = tfm,
		.src = src,
		.dst = dst,
		.slen = slen,
		.dlen = dlen,
	};

	return crypto_akcipher_sync_prep(&data) ?:
	       crypto_akcipher_sync_post(&data,
					 crypto_akcipher_encrypt(data.req));
}
EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);

int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
				 const void *src, unsigned int slen,
				 void *dst, unsigned int dlen)
{
	struct crypto_akcipher_sync_data data = {
		.tfm = tfm,
		.src = src,
		.dst = dst,
		.slen = slen,
		.dlen = dlen,
	};

	return crypto_akcipher_sync_prep(&data) ?:
	       crypto_akcipher_sync_post(&data,
					 crypto_akcipher_decrypt(data.req)) ?:
	       data.dlen;
}
EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);

static void crypto_exit_akcipher_ops_sig(struct crypto_tfm *tfm)
{
	struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm);

	crypto_free_akcipher(*ctx);
}

int crypto_init_akcipher_ops_sig(struct crypto_tfm *tfm)
{
	struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm);
	struct crypto_alg *calg = tfm->__crt_alg;
	struct crypto_akcipher *akcipher;

	if (!crypto_mod_get(calg))
		return -EAGAIN;

	akcipher = crypto_create_tfm(calg, &crypto_akcipher_type);
	if (IS_ERR(akcipher)) {
		crypto_mod_put(calg);
		return PTR_ERR(akcipher);
	}

	*ctx = akcipher;
	tfm->exit = crypto_exit_akcipher_ops_sig;

	return 0;
}
EXPORT_SYMBOL_GPL(crypto_init_akcipher_ops_sig);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Generic public key cipher type");