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(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(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(tfm)) ||
79	    authsize > crypto_aead_maxauthsize(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(&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(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(&istat->encrypt_cnt);
115		atomic64_add(req->cryptlen, &istat->encrypt_tlen);
116	}
117
118	if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
119		ret = -ENOKEY;
120	else
121		ret = alg->encrypt(req);
122
123	return crypto_aead_errstat(istat, 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(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(&istat->encrypt_cnt);
138		atomic64_add(req->cryptlen, &istat->encrypt_tlen);
139	}
140
141	if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
142		ret = -ENOKEY;
143	else if (req->cryptlen < crypto_aead_authsize(aead))
144		ret = -EINVAL;
145	else
146		ret = alg->decrypt(req);
147
148	return crypto_aead_errstat(istat, 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(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(aead);
164
165	crypto_aead_set_flags(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(raead.type, "aead", sizeof(raead.type));
187	strscpy(raead.geniv, "<none>", 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, CRYPTOCFGA_REPORT_AEAD, sizeof(raead), &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, "type         : aead\n");
203	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
204					     "yes" : "no");
205	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
206	seq_printf(m, "ivsize       : %u\n", aead->ivsize);
207	seq_printf(m, "maxauthsize  : %u\n", aead->maxauthsize);
208	seq_printf(m, "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(aead);
223	struct crypto_stat_aead raead;
224
225	memset(&raead, 0, sizeof(raead));
226
227	strscpy(raead.type, "aead", sizeof(raead.type));
228
229	raead.stat_encrypt_cnt = atomic64_read(&istat->encrypt_cnt);
230	raead.stat_encrypt_tlen = atomic64_read(&istat->encrypt_tlen);
231	raead.stat_decrypt_cnt = atomic64_read(&istat->decrypt_cnt);
232	raead.stat_decrypt_tlen = atomic64_read(&istat->decrypt_tlen);
233	raead.stat_err_cnt = atomic64_read(&istat->err_cnt);
234
235	return nla_put(skb, CRYPTOCFGA_STAT_AEAD, sizeof(raead), &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->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, &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(alg_name, &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(base);
310}
311EXPORT_SYMBOL_GPL(crypto_register_aead);
312
313void crypto_unregister_aead(struct aead_alg *alg)
314{
315	crypto_unregister_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(&inst->alg);
357	if (err)
358		return err;
359
360	return crypto_register_instance(tmpl, aead_crypto_instance(inst));
361}
362EXPORT_SYMBOL_GPL(aead_register_instance);
363
364MODULE_LICENSE("GPL");
365MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
366