1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Public Key Encryption
4 *
5 * Copyright (c) 2015, Intel Corporation
6 * Authors: Tadeusz Struk <tadeusz.struk@intel.com>
7 */
8#include <crypto/internal/akcipher.h>
9#include <linux/cryptouser.h>
10#include <linux/errno.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/scatterlist.h>
14#include <linux/seq_file.h>
15#include <linux/slab.h>
16#include <linux/string.h>
17#include <net/netlink.h>
18
19#include "internal.h"
20
21#define CRYPTO_ALG_TYPE_AHASH_MASK	0x0000000e
22
23static int __maybe_unused crypto_akcipher_report(
24	struct sk_buff *skb, struct crypto_alg *alg)
25{
26	struct crypto_report_akcipher rakcipher;
27
28	memset(&rakcipher, 0, sizeof(rakcipher));
29
30	strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
31
32	return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
33		       sizeof(rakcipher), &rakcipher);
34}
35
36static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
37	__maybe_unused;
38
39static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
40{
41	seq_puts(m, "type         : akcipher\n");
42}
43
44static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
45{
46	struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
47	struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
48
49	alg->exit(akcipher);
50}
51
52static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
53{
54	struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
55	struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
56
57	if (alg->exit)
58		akcipher->base.exit = crypto_akcipher_exit_tfm;
59
60	if (alg->init)
61		return alg->init(akcipher);
62
63	return 0;
64}
65
66static void crypto_akcipher_free_instance(struct crypto_instance *inst)
67{
68	struct akcipher_instance *akcipher = akcipher_instance(inst);
69
70	akcipher->free(akcipher);
71}
72
73static int __maybe_unused crypto_akcipher_report_stat(
74	struct sk_buff *skb, struct crypto_alg *alg)
75{
76	struct akcipher_alg *akcipher = __crypto_akcipher_alg(alg);
77	struct crypto_istat_akcipher *istat;
78	struct crypto_stat_akcipher rakcipher;
79
80	istat = akcipher_get_stat(akcipher);
81
82	memset(&rakcipher, 0, sizeof(rakcipher));
83
84	strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
85	rakcipher.stat_encrypt_cnt = atomic64_read(&istat->encrypt_cnt);
86	rakcipher.stat_encrypt_tlen = atomic64_read(&istat->encrypt_tlen);
87	rakcipher.stat_decrypt_cnt = atomic64_read(&istat->decrypt_cnt);
88	rakcipher.stat_decrypt_tlen = atomic64_read(&istat->decrypt_tlen);
89	rakcipher.stat_sign_cnt = atomic64_read(&istat->sign_cnt);
90	rakcipher.stat_verify_cnt = atomic64_read(&istat->verify_cnt);
91	rakcipher.stat_err_cnt = atomic64_read(&istat->err_cnt);
92
93	return nla_put(skb, CRYPTOCFGA_STAT_AKCIPHER,
94		       sizeof(rakcipher), &rakcipher);
95}
96
97static const struct crypto_type crypto_akcipher_type = {
98	.extsize = crypto_alg_extsize,
99	.init_tfm = crypto_akcipher_init_tfm,
100	.free = crypto_akcipher_free_instance,
101#ifdef CONFIG_PROC_FS
102	.show = crypto_akcipher_show,
103#endif
104#if IS_ENABLED(CONFIG_CRYPTO_USER)
105	.report = crypto_akcipher_report,
106#endif
107#ifdef CONFIG_CRYPTO_STATS
108	.report_stat = crypto_akcipher_report_stat,
109#endif
110	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
111	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
112	.type = CRYPTO_ALG_TYPE_AKCIPHER,
113	.tfmsize = offsetof(struct crypto_akcipher, base),
114};
115
116int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
117			 struct crypto_instance *inst,
118			 const char *name, u32 type, u32 mask)
119{
120	spawn->base.frontend = &crypto_akcipher_type;
121	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
122}
123EXPORT_SYMBOL_GPL(crypto_grab_akcipher);
124
125struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
126					      u32 mask)
127{
128	return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
129}
130EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);
131
132static void akcipher_prepare_alg(struct akcipher_alg *alg)
133{
134	struct crypto_istat_akcipher *istat = akcipher_get_stat(alg);
135	struct crypto_alg *base = &alg->base;
136
137	base->cra_type = &crypto_akcipher_type;
138	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
139	base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
140
141	if (IS_ENABLED(CONFIG_CRYPTO_STATS))
142		memset(istat, 0, sizeof(*istat));
143}
144
145static int akcipher_default_op(struct akcipher_request *req)
146{
147	return -ENOSYS;
148}
149
150static int akcipher_default_set_key(struct crypto_akcipher *tfm,
151				     const void *key, unsigned int keylen)
152{
153	return -ENOSYS;
154}
155
156int crypto_register_akcipher(struct akcipher_alg *alg)
157{
158	struct crypto_alg *base = &alg->base;
159
160	if (!alg->sign)
161		alg->sign = akcipher_default_op;
162	if (!alg->verify)
163		alg->verify = akcipher_default_op;
164	if (!alg->encrypt)
165		alg->encrypt = akcipher_default_op;
166	if (!alg->decrypt)
167		alg->decrypt = akcipher_default_op;
168	if (!alg->set_priv_key)
169		alg->set_priv_key = akcipher_default_set_key;
170
171	akcipher_prepare_alg(alg);
172	return crypto_register_alg(base);
173}
174EXPORT_SYMBOL_GPL(crypto_register_akcipher);
175
176void crypto_unregister_akcipher(struct akcipher_alg *alg)
177{
178	crypto_unregister_alg(&alg->base);
179}
180EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
181
182int akcipher_register_instance(struct crypto_template *tmpl,
183			       struct akcipher_instance *inst)
184{
185	if (WARN_ON(!inst->free))
186		return -EINVAL;
187	akcipher_prepare_alg(&inst->alg);
188	return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
189}
190EXPORT_SYMBOL_GPL(akcipher_register_instance);
191
192int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
193{
194	unsigned int reqsize = crypto_akcipher_reqsize(data->tfm);
195	struct akcipher_request *req;
196	struct scatterlist *sg;
197	unsigned int mlen;
198	unsigned int len;
199	u8 *buf;
200
201	if (data->dst)
202		mlen = max(data->slen, data->dlen);
203	else
204		mlen = data->slen + data->dlen;
205
206	len = sizeof(*req) + reqsize + mlen;
207	if (len < mlen)
208		return -EOVERFLOW;
209
210	req = kzalloc(len, GFP_KERNEL);
211	if (!req)
212		return -ENOMEM;
213
214	data->req = req;
215	akcipher_request_set_tfm(req, data->tfm);
216
217	buf = (u8 *)(req + 1) + reqsize;
218	data->buf = buf;
219	memcpy(buf, data->src, data->slen);
220
221	sg = &data->sg;
222	sg_init_one(sg, buf, mlen);
223	akcipher_request_set_crypt(req, sg, data->dst ? sg : NULL,
224				   data->slen, data->dlen);
225
226	crypto_init_wait(&data->cwait);
227	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
228				      crypto_req_done, &data->cwait);
229
230	return 0;
231}
232EXPORT_SYMBOL_GPL(crypto_akcipher_sync_prep);
233
234int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data, int err)
235{
236	err = crypto_wait_req(err, &data->cwait);
237	if (data->dst)
238		memcpy(data->dst, data->buf, data->dlen);
239	data->dlen = data->req->dst_len;
240	kfree_sensitive(data->req);
241	return err;
242}
243EXPORT_SYMBOL_GPL(crypto_akcipher_sync_post);
244
245int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
246				 const void *src, unsigned int slen,
247				 void *dst, unsigned int dlen)
248{
249	struct crypto_akcipher_sync_data data = {
250		.tfm = tfm,
251		.src = src,
252		.dst = dst,
253		.slen = slen,
254		.dlen = dlen,
255	};
256
257	return crypto_akcipher_sync_prep(&data) ?:
258	       crypto_akcipher_sync_post(&data,
259					 crypto_akcipher_encrypt(data.req));
260}
261EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);
262
263int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
264				 const void *src, unsigned int slen,
265				 void *dst, unsigned int dlen)
266{
267	struct crypto_akcipher_sync_data data = {
268		.tfm = tfm,
269		.src = src,
270		.dst = dst,
271		.slen = slen,
272		.dlen = dlen,
273	};
274
275	return crypto_akcipher_sync_prep(&data) ?:
276	       crypto_akcipher_sync_post(&data,
277					 crypto_akcipher_decrypt(data.req)) ?:
278	       data.dlen;
279}
280EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);
281
282static void crypto_exit_akcipher_ops_sig(struct crypto_tfm *tfm)
283{
284	struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm);
285
286	crypto_free_akcipher(*ctx);
287}
288
289int crypto_init_akcipher_ops_sig(struct crypto_tfm *tfm)
290{
291	struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm);
292	struct crypto_alg *calg = tfm->__crt_alg;
293	struct crypto_akcipher *akcipher;
294
295	if (!crypto_mod_get(calg))
296		return -EAGAIN;
297
298	akcipher = crypto_create_tfm(calg, &crypto_akcipher_type);
299	if (IS_ERR(akcipher)) {
300		crypto_mod_put(calg);
301		return PTR_ERR(akcipher);
302	}
303
304	*ctx = akcipher;
305	tfm->exit = crypto_exit_akcipher_ops_sig;
306
307	return 0;
308}
309EXPORT_SYMBOL_GPL(crypto_init_akcipher_ops_sig);
310
311MODULE_LICENSE("GPL");
312MODULE_DESCRIPTION("Generic public key cipher type");
313