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
23struct crypto_akcipher_sync_data {
24 struct crypto_akcipher *tfm;
25 const void *src;
26 void *dst;
27 unsigned int slen;
28 unsigned int dlen;
29
30 struct akcipher_request *req;
31 struct crypto_wait cwait;
32 struct scatterlist sg;
33 u8 *buf;
34};
35
36static int __maybe_unused crypto_akcipher_report(
37 struct sk_buff *skb, struct crypto_alg *alg)
38{
39 struct crypto_report_akcipher rakcipher;
40
41 memset(s: &rakcipher, c: 0, n: sizeof(rakcipher));
42
43 strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
44
45 return nla_put(skb, attrtype: CRYPTOCFGA_REPORT_AKCIPHER,
46 attrlen: sizeof(rakcipher), data: &rakcipher);
47}
48
49static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
50 __maybe_unused;
51
52static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
53{
54 seq_puts(m, s: "type : akcipher\n");
55}
56
57static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
58{
59 struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
60 struct akcipher_alg *alg = crypto_akcipher_alg(tfm: akcipher);
61
62 alg->exit(akcipher);
63}
64
65static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
66{
67 struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
68 struct akcipher_alg *alg = crypto_akcipher_alg(tfm: akcipher);
69
70 if (alg->exit)
71 akcipher->base.exit = crypto_akcipher_exit_tfm;
72
73 if (alg->init)
74 return alg->init(akcipher);
75
76 return 0;
77}
78
79static void crypto_akcipher_free_instance(struct crypto_instance *inst)
80{
81 struct akcipher_instance *akcipher = akcipher_instance(inst);
82
83 akcipher->free(akcipher);
84}
85
86static const struct crypto_type crypto_akcipher_type = {
87 .extsize = crypto_alg_extsize,
88 .init_tfm = crypto_akcipher_init_tfm,
89 .free = crypto_akcipher_free_instance,
90#ifdef CONFIG_PROC_FS
91 .show = crypto_akcipher_show,
92#endif
93#if IS_ENABLED(CONFIG_CRYPTO_USER)
94 .report = crypto_akcipher_report,
95#endif
96 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
97 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
98 .type = CRYPTO_ALG_TYPE_AKCIPHER,
99 .tfmsize = offsetof(struct crypto_akcipher, base),
100 .algsize = offsetof(struct akcipher_alg, base),
101};
102
103int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
104 struct crypto_instance *inst,
105 const char *name, u32 type, u32 mask)
106{
107 spawn->base.frontend = &crypto_akcipher_type;
108 return crypto_grab_spawn(spawn: &spawn->base, inst, name, type, mask);
109}
110EXPORT_SYMBOL_GPL(crypto_grab_akcipher);
111
112struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
113 u32 mask)
114{
115 return crypto_alloc_tfm(alg_name, frontend: &crypto_akcipher_type, type, mask);
116}
117EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);
118
119static void akcipher_prepare_alg(struct akcipher_alg *alg)
120{
121 struct crypto_alg *base = &alg->base;
122
123 base->cra_type = &crypto_akcipher_type;
124 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
125 base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
126}
127
128static int akcipher_default_op(struct akcipher_request *req)
129{
130 return -ENOSYS;
131}
132
133static int akcipher_default_set_key(struct crypto_akcipher *tfm,
134 const void *key, unsigned int keylen)
135{
136 return -ENOSYS;
137}
138
139int crypto_register_akcipher(struct akcipher_alg *alg)
140{
141 struct crypto_alg *base = &alg->base;
142
143 if (!alg->encrypt)
144 alg->encrypt = akcipher_default_op;
145 if (!alg->decrypt)
146 alg->decrypt = akcipher_default_op;
147 if (!alg->set_priv_key)
148 alg->set_priv_key = akcipher_default_set_key;
149
150 akcipher_prepare_alg(alg);
151 return crypto_register_alg(alg: base);
152}
153EXPORT_SYMBOL_GPL(crypto_register_akcipher);
154
155void crypto_unregister_akcipher(struct akcipher_alg *alg)
156{
157 crypto_unregister_alg(alg: &alg->base);
158}
159EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
160
161int akcipher_register_instance(struct crypto_template *tmpl,
162 struct akcipher_instance *inst)
163{
164 if (WARN_ON(!inst->free))
165 return -EINVAL;
166 akcipher_prepare_alg(alg: &inst->alg);
167 return crypto_register_instance(tmpl, inst: akcipher_crypto_instance(inst));
168}
169EXPORT_SYMBOL_GPL(akcipher_register_instance);
170
171static int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
172{
173 unsigned int reqsize = crypto_akcipher_reqsize(tfm: data->tfm);
174 struct akcipher_request *req;
175 struct scatterlist *sg;
176 unsigned int mlen;
177 unsigned int len;
178 u8 *buf;
179
180 mlen = max(data->slen, data->dlen);
181
182 len = sizeof(*req) + reqsize + mlen;
183 if (len < mlen)
184 return -EOVERFLOW;
185
186 req = kzalloc(len, GFP_KERNEL);
187 if (!req)
188 return -ENOMEM;
189
190 data->req = req;
191 akcipher_request_set_tfm(req, tfm: data->tfm);
192
193 buf = (u8 *)(req + 1) + reqsize;
194 data->buf = buf;
195 memcpy(to: buf, from: data->src, len: data->slen);
196
197 sg = &data->sg;
198 sg_init_one(sg, buf, mlen);
199 akcipher_request_set_crypt(req, src: sg, dst: sg, src_len: data->slen, dst_len: data->dlen);
200
201 crypto_init_wait(wait: &data->cwait);
202 akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
203 cmpl: crypto_req_done, data: &data->cwait);
204
205 return 0;
206}
207
208static int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data,
209 int err)
210{
211 err = crypto_wait_req(err, wait: &data->cwait);
212 memcpy(to: data->dst, from: data->buf, len: data->dlen);
213 data->dlen = data->req->dst_len;
214 kfree_sensitive(objp: data->req);
215 return err;
216}
217
218int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
219 const void *src, unsigned int slen,
220 void *dst, unsigned int dlen)
221{
222 struct crypto_akcipher_sync_data data = {
223 .tfm = tfm,
224 .src = src,
225 .dst = dst,
226 .slen = slen,
227 .dlen = dlen,
228 };
229
230 return crypto_akcipher_sync_prep(data: &data) ?:
231 crypto_akcipher_sync_post(data: &data,
232 err: crypto_akcipher_encrypt(req: data.req));
233}
234EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);
235
236int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
237 const void *src, unsigned int slen,
238 void *dst, unsigned int dlen)
239{
240 struct crypto_akcipher_sync_data data = {
241 .tfm = tfm,
242 .src = src,
243 .dst = dst,
244 .slen = slen,
245 .dlen = dlen,
246 };
247
248 return crypto_akcipher_sync_prep(data: &data) ?:
249 crypto_akcipher_sync_post(data: &data,
250 err: crypto_akcipher_decrypt(req: data.req)) ?:
251 data.dlen;
252}
253EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);
254
255MODULE_LICENSE("GPL");
256MODULE_DESCRIPTION("Generic public key cipher type");
257