1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * AEAD: Authenticated Encryption with Associated Data
4 *
5 * This file provides API support for AEAD algorithms.
6 *
7 * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
8 */
9
10#include <crypto/internal/aead.h>
11#include <linux/cryptouser.h>
12#include <linux/errno.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/seq_file.h>
18#include <linux/string.h>
19#include <net/netlink.h>
20
21#include "internal.h"
22
23static inline struct crypto_istat_aead *aead_get_stat(struct aead_alg *alg)
24{
25#ifdef CONFIG_CRYPTO_STATS
26 return &alg->stat;
27#else
28 return NULL;
29#endif
30}
31
32static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
33 unsigned int keylen)
34{
35 unsigned long alignmask = crypto_aead_alignmask(tfm);
36 int ret;
37 u8 *buffer, *alignbuffer;
38 unsigned long absize;
39
40 absize = keylen + alignmask;
41 buffer = kmalloc(size: absize, GFP_ATOMIC);
42 if (!buffer)
43 return -ENOMEM;
44
45 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
46 memcpy(alignbuffer, key, keylen);
47 ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
48 memset(alignbuffer, 0, keylen);
49 kfree(objp: buffer);
50 return ret;
51}
52
53int crypto_aead_setkey(struct crypto_aead *tfm,
54 const u8 *key, unsigned int keylen)
55{
56 unsigned long alignmask = crypto_aead_alignmask(tfm);
57 int err;
58
59 if ((unsigned long)key & alignmask)
60 err = setkey_unaligned(tfm, key, keylen);
61 else
62 err = crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
63
64 if (unlikely(err)) {
65 crypto_aead_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
66 return err;
67 }
68
69 crypto_aead_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
70 return 0;
71}
72EXPORT_SYMBOL_GPL(crypto_aead_setkey);
73
74int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
75{
76 int err;
77
78 if ((!authsize && crypto_aead_maxauthsize(aead: tfm)) ||
79 authsize > crypto_aead_maxauthsize(aead: tfm))
80 return -EINVAL;
81
82 if (crypto_aead_alg(tfm)->setauthsize) {
83 err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize);
84 if (err)
85 return err;
86 }
87
88 tfm->authsize = authsize;
89 return 0;
90}
91EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
92
93static inline int crypto_aead_errstat(struct crypto_istat_aead *istat, int err)
94{
95 if (!IS_ENABLED(CONFIG_CRYPTO_STATS))
96 return err;
97
98 if (err && err != -EINPROGRESS && err != -EBUSY)
99 atomic64_inc(v: &istat->err_cnt);
100
101 return err;
102}
103
104int crypto_aead_encrypt(struct aead_request *req)
105{
106 struct crypto_aead *aead = crypto_aead_reqtfm(req);
107 struct aead_alg *alg = crypto_aead_alg(tfm: aead);
108 struct crypto_istat_aead *istat;
109 int ret;
110
111 istat = aead_get_stat(alg);
112
113 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
114 atomic64_inc(v: &istat->encrypt_cnt);
115 atomic64_add(i: req->cryptlen, v: &istat->encrypt_tlen);
116 }
117
118 if (crypto_aead_get_flags(tfm: aead) & CRYPTO_TFM_NEED_KEY)
119 ret = -ENOKEY;
120 else
121 ret = alg->encrypt(req);
122
123 return crypto_aead_errstat(istat, err: ret);
124}
125EXPORT_SYMBOL_GPL(crypto_aead_encrypt);
126
127int crypto_aead_decrypt(struct aead_request *req)
128{
129 struct crypto_aead *aead = crypto_aead_reqtfm(req);
130 struct aead_alg *alg = crypto_aead_alg(tfm: aead);
131 struct crypto_istat_aead *istat;
132 int ret;
133
134 istat = aead_get_stat(alg);
135
136 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
137 atomic64_inc(v: &istat->encrypt_cnt);
138 atomic64_add(i: req->cryptlen, v: &istat->encrypt_tlen);
139 }
140
141 if (crypto_aead_get_flags(tfm: aead) & CRYPTO_TFM_NEED_KEY)
142 ret = -ENOKEY;
143 else if (req->cryptlen < crypto_aead_authsize(tfm: aead))
144 ret = -EINVAL;
145 else
146 ret = alg->decrypt(req);
147
148 return crypto_aead_errstat(istat, err: ret);
149}
150EXPORT_SYMBOL_GPL(crypto_aead_decrypt);
151
152static void crypto_aead_exit_tfm(struct crypto_tfm *tfm)
153{
154 struct crypto_aead *aead = __crypto_aead_cast(tfm);
155 struct aead_alg *alg = crypto_aead_alg(tfm: aead);
156
157 alg->exit(aead);
158}
159
160static int crypto_aead_init_tfm(struct crypto_tfm *tfm)
161{
162 struct crypto_aead *aead = __crypto_aead_cast(tfm);
163 struct aead_alg *alg = crypto_aead_alg(tfm: aead);
164
165 crypto_aead_set_flags(tfm: aead, CRYPTO_TFM_NEED_KEY);
166
167 aead->authsize = alg->maxauthsize;
168
169 if (alg->exit)
170 aead->base.exit = crypto_aead_exit_tfm;
171
172 if (alg->init)
173 return alg->init(aead);
174
175 return 0;
176}
177
178static int __maybe_unused crypto_aead_report(
179 struct sk_buff *skb, struct crypto_alg *alg)
180{
181 struct crypto_report_aead raead;
182 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
183
184 memset(&raead, 0, sizeof(raead));
185
186 strscpy(p: raead.type, q: "aead", size: sizeof(raead.type));
187 strscpy(p: raead.geniv, q: "<none>", size: sizeof(raead.geniv));
188
189 raead.blocksize = alg->cra_blocksize;
190 raead.maxauthsize = aead->maxauthsize;
191 raead.ivsize = aead->ivsize;
192
193 return nla_put(skb, attrtype: CRYPTOCFGA_REPORT_AEAD, attrlen: sizeof(raead), data: &raead);
194}
195
196static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
197 __maybe_unused;
198static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
199{
200 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
201
202 seq_printf(m, fmt: "type : aead\n");
203 seq_printf(m, fmt: "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
204 "yes" : "no");
205 seq_printf(m, fmt: "blocksize : %u\n", alg->cra_blocksize);
206 seq_printf(m, fmt: "ivsize : %u\n", aead->ivsize);
207 seq_printf(m, fmt: "maxauthsize : %u\n", aead->maxauthsize);
208 seq_printf(m, fmt: "geniv : <none>\n");
209}
210
211static void crypto_aead_free_instance(struct crypto_instance *inst)
212{
213 struct aead_instance *aead = aead_instance(inst);
214
215 aead->free(aead);
216}
217
218static int __maybe_unused crypto_aead_report_stat(
219 struct sk_buff *skb, struct crypto_alg *alg)
220{
221 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
222 struct crypto_istat_aead *istat = aead_get_stat(alg: aead);
223 struct crypto_stat_aead raead;
224
225 memset(&raead, 0, sizeof(raead));
226
227 strscpy(p: raead.type, q: "aead", size: sizeof(raead.type));
228
229 raead.stat_encrypt_cnt = atomic64_read(v: &istat->encrypt_cnt);
230 raead.stat_encrypt_tlen = atomic64_read(v: &istat->encrypt_tlen);
231 raead.stat_decrypt_cnt = atomic64_read(v: &istat->decrypt_cnt);
232 raead.stat_decrypt_tlen = atomic64_read(v: &istat->decrypt_tlen);
233 raead.stat_err_cnt = atomic64_read(v: &istat->err_cnt);
234
235 return nla_put(skb, attrtype: CRYPTOCFGA_STAT_AEAD, attrlen: sizeof(raead), data: &raead);
236}
237
238static const struct crypto_type crypto_aead_type = {
239 .extsize = crypto_alg_extsize,
240 .init_tfm = crypto_aead_init_tfm,
241 .free = crypto_aead_free_instance,
242#ifdef CONFIG_PROC_FS
243 .show = crypto_aead_show,
244#endif
245#if IS_ENABLED(CONFIG_CRYPTO_USER)
246 .report = crypto_aead_report,
247#endif
248#ifdef CONFIG_CRYPTO_STATS
249 .report_stat = crypto_aead_report_stat,
250#endif
251 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
252 .maskset = CRYPTO_ALG_TYPE_MASK,
253 .type = CRYPTO_ALG_TYPE_AEAD,
254 .tfmsize = offsetof(struct crypto_aead, base),
255};
256
257int crypto_grab_aead(struct crypto_aead_spawn *spawn,
258 struct crypto_instance *inst,
259 const char *name, u32 type, u32 mask)
260{
261 spawn->base.frontend = &crypto_aead_type;
262 return crypto_grab_spawn(spawn: &spawn->base, inst, name, type, mask);
263}
264EXPORT_SYMBOL_GPL(crypto_grab_aead);
265
266struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
267{
268 return crypto_alloc_tfm(alg_name, frontend: &crypto_aead_type, type, mask);
269}
270EXPORT_SYMBOL_GPL(crypto_alloc_aead);
271
272int crypto_has_aead(const char *alg_name, u32 type, u32 mask)
273{
274 return crypto_type_has_alg(name: alg_name, frontend: &crypto_aead_type, type, mask);
275}
276EXPORT_SYMBOL_GPL(crypto_has_aead);
277
278static int aead_prepare_alg(struct aead_alg *alg)
279{
280 struct crypto_istat_aead *istat = aead_get_stat(alg);
281 struct crypto_alg *base = &alg->base;
282
283 if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) >
284 PAGE_SIZE / 8)
285 return -EINVAL;
286
287 if (!alg->chunksize)
288 alg->chunksize = base->cra_blocksize;
289
290 base->cra_type = &crypto_aead_type;
291 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
292 base->cra_flags |= CRYPTO_ALG_TYPE_AEAD;
293
294 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
295 memset(istat, 0, sizeof(*istat));
296
297 return 0;
298}
299
300int crypto_register_aead(struct aead_alg *alg)
301{
302 struct crypto_alg *base = &alg->base;
303 int err;
304
305 err = aead_prepare_alg(alg);
306 if (err)
307 return err;
308
309 return crypto_register_alg(alg: base);
310}
311EXPORT_SYMBOL_GPL(crypto_register_aead);
312
313void crypto_unregister_aead(struct aead_alg *alg)
314{
315 crypto_unregister_alg(alg: &alg->base);
316}
317EXPORT_SYMBOL_GPL(crypto_unregister_aead);
318
319int crypto_register_aeads(struct aead_alg *algs, int count)
320{
321 int i, ret;
322
323 for (i = 0; i < count; i++) {
324 ret = crypto_register_aead(&algs[i]);
325 if (ret)
326 goto err;
327 }
328
329 return 0;
330
331err:
332 for (--i; i >= 0; --i)
333 crypto_unregister_aead(&algs[i]);
334
335 return ret;
336}
337EXPORT_SYMBOL_GPL(crypto_register_aeads);
338
339void crypto_unregister_aeads(struct aead_alg *algs, int count)
340{
341 int i;
342
343 for (i = count - 1; i >= 0; --i)
344 crypto_unregister_aead(&algs[i]);
345}
346EXPORT_SYMBOL_GPL(crypto_unregister_aeads);
347
348int aead_register_instance(struct crypto_template *tmpl,
349 struct aead_instance *inst)
350{
351 int err;
352
353 if (WARN_ON(!inst->free))
354 return -EINVAL;
355
356 err = aead_prepare_alg(alg: &inst->alg);
357 if (err)
358 return err;
359
360 return crypto_register_instance(tmpl, inst: aead_crypto_instance(inst));
361}
362EXPORT_SYMBOL_GPL(aead_register_instance);
363
364MODULE_LICENSE("GPL");
365MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
366

source code of linux/crypto/aead.c