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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 <[email protected]>
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 <linux/string_choices.h>
20#include <net/netlink.h>
21
22#include "internal.h"
23
24static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
25 unsigned int keylen)
26{
27 unsigned long alignmask = crypto_aead_alignmask(tfm);
28 int ret;
29 u8 *buffer, *alignbuffer;
30 unsigned long absize;
31
32 absize = keylen + alignmask;
33 buffer = kmalloc(absize, GFP_ATOMIC);
34 if (!buffer)
35 return -ENOMEM;
36
37 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
38 memcpy(alignbuffer, key, keylen);
39 ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
40 kfree_sensitive(buffer);
41 return ret;
42}
43
44int crypto_aead_setkey(struct crypto_aead *tfm,
45 const u8 *key, unsigned int keylen)
46{
47 unsigned long alignmask = crypto_aead_alignmask(tfm);
48 int err;
49
50 if ((unsigned long)key & alignmask)
51 err = setkey_unaligned(tfm, key, keylen);
52 else
53 err = crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
54
55 if (unlikely(err)) {
56 crypto_aead_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
57 return err;
58 }
59
60 crypto_aead_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
61 return 0;
62}
63EXPORT_SYMBOL_GPL(crypto_aead_setkey);
64
65int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
66{
67 int err;
68
69 if ((!authsize && crypto_aead_maxauthsize(tfm)) ||
70 authsize > crypto_aead_maxauthsize(tfm))
71 return -EINVAL;
72
73 if (crypto_aead_alg(tfm)->setauthsize) {
74 err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize);
75 if (err)
76 return err;
77 }
78
79 tfm->authsize = authsize;
80 return 0;
81}
82EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
83
84int crypto_aead_encrypt(struct aead_request *req)
85{
86 struct crypto_aead *aead = crypto_aead_reqtfm(req);
87
88 if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
89 return -ENOKEY;
90
91 return crypto_aead_alg(aead)->encrypt(req);
92}
93EXPORT_SYMBOL_GPL(crypto_aead_encrypt);
94
95int crypto_aead_decrypt(struct aead_request *req)
96{
97 struct crypto_aead *aead = crypto_aead_reqtfm(req);
98
99 if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
100 return -ENOKEY;
101
102 if (req->cryptlen < crypto_aead_authsize(aead))
103 return -EINVAL;
104
105 return crypto_aead_alg(aead)->decrypt(req);
106}
107EXPORT_SYMBOL_GPL(crypto_aead_decrypt);
108
109static void crypto_aead_exit_tfm(struct crypto_tfm *tfm)
110{
111 struct crypto_aead *aead = __crypto_aead_cast(tfm);
112 struct aead_alg *alg = crypto_aead_alg(aead);
113
114 alg->exit(aead);
115}
116
117static int crypto_aead_init_tfm(struct crypto_tfm *tfm)
118{
119 struct crypto_aead *aead = __crypto_aead_cast(tfm);
120 struct aead_alg *alg = crypto_aead_alg(aead);
121
122 crypto_aead_set_flags(aead, CRYPTO_TFM_NEED_KEY);
123 crypto_aead_set_reqsize(aead, crypto_tfm_alg_reqsize(tfm));
124
125 aead->authsize = alg->maxauthsize;
126
127 if (alg->exit)
128 aead->base.exit = crypto_aead_exit_tfm;
129
130 if (alg->init)
131 return alg->init(aead);
132
133 return 0;
134}
135
136static int __maybe_unused crypto_aead_report(
137 struct sk_buff *skb, struct crypto_alg *alg)
138{
139 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
140 struct crypto_report_aead raead = {
141 .type = "aead",
142 .geniv = "<none>",
143 };
144
145 raead.blocksize = alg->cra_blocksize;
146 raead.maxauthsize = aead->maxauthsize;
147 raead.ivsize = aead->ivsize;
148
149 return nla_put(skb, CRYPTOCFGA_REPORT_AEAD, sizeof(raead), &raead);
150}
151
152static void __maybe_unused crypto_aead_show(struct seq_file *m,
153 struct crypto_alg *alg)
154{
155 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
156
157 seq_printf(m, "type : aead\n");
158 seq_printf(m, "async : %s\n",
159 str_yes_no(alg->cra_flags & CRYPTO_ALG_ASYNC));
160 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
161 seq_printf(m, "ivsize : %u\n", aead->ivsize);
162 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
163 seq_printf(m, "geniv : <none>\n");
164}
165
166static void crypto_aead_free_instance(struct crypto_instance *inst)
167{
168 struct aead_instance *aead = aead_instance(inst);
169
170 aead->free(aead);
171}
172
173static const struct crypto_type crypto_aead_type = {
174 .extsize = crypto_alg_extsize,
175 .init_tfm = crypto_aead_init_tfm,
176 .free = crypto_aead_free_instance,
177#ifdef CONFIG_PROC_FS
178 .show = crypto_aead_show,
179#endif
180#if IS_ENABLED(CONFIG_CRYPTO_USER)
181 .report = crypto_aead_report,
182#endif
183 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
184 .maskset = CRYPTO_ALG_TYPE_MASK,
185 .type = CRYPTO_ALG_TYPE_AEAD,
186 .tfmsize = offsetof(struct crypto_aead, base),
187 .algsize = offsetof(struct aead_alg, base),
188};
189
190int crypto_grab_aead(struct crypto_aead_spawn *spawn,
191 struct crypto_instance *inst,
192 const char *name, u32 type, u32 mask)
193{
194 spawn->base.frontend = &crypto_aead_type;
195 return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
196}
197EXPORT_SYMBOL_GPL(crypto_grab_aead);
198
199struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
200{
201 return crypto_alloc_tfm(alg_name, &crypto_aead_type, type, mask);
202}
203EXPORT_SYMBOL_GPL(crypto_alloc_aead);
204
205struct crypto_sync_aead *crypto_alloc_sync_aead(const char *alg_name, u32 type, u32 mask)
206{
207 struct crypto_aead *tfm;
208
209 /* Only sync algorithms are allowed. */
210 mask |= CRYPTO_ALG_ASYNC;
211 type &= ~(CRYPTO_ALG_ASYNC);
212
213 tfm = crypto_alloc_tfm(alg_name, &crypto_aead_type, type, mask);
214
215 if (!IS_ERR(tfm) && WARN_ON(crypto_aead_reqsize(tfm) > MAX_SYNC_AEAD_REQSIZE)) {
216 crypto_free_aead(tfm);
217 return ERR_PTR(-EINVAL);
218 }
219
220 return (struct crypto_sync_aead *)tfm;
221}
222EXPORT_SYMBOL_GPL(crypto_alloc_sync_aead);
223
224int crypto_has_aead(const char *alg_name, u32 type, u32 mask)
225{
226 return crypto_type_has_alg(alg_name, &crypto_aead_type, type, mask);
227}
228EXPORT_SYMBOL_GPL(crypto_has_aead);
229
230static int aead_prepare_alg(struct aead_alg *alg)
231{
232 struct crypto_alg *base = &alg->base;
233
234 if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) >
235 PAGE_SIZE / 8)
236 return -EINVAL;
237
238 if (!alg->chunksize)
239 alg->chunksize = base->cra_blocksize;
240
241 base->cra_type = &crypto_aead_type;
242 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
243 base->cra_flags |= CRYPTO_ALG_TYPE_AEAD;
244
245 return 0;
246}
247
248int crypto_register_aead(struct aead_alg *alg)
249{
250 struct crypto_alg *base = &alg->base;
251 int err;
252
253 err = aead_prepare_alg(alg);
254 if (err)
255 return err;
256
257 return crypto_register_alg(base);
258}
259EXPORT_SYMBOL_GPL(crypto_register_aead);
260
261void crypto_unregister_aead(struct aead_alg *alg)
262{
263 crypto_unregister_alg(&alg->base);
264}
265EXPORT_SYMBOL_GPL(crypto_unregister_aead);
266
267int crypto_register_aeads(struct aead_alg *algs, int count)
268{
269 int i, ret;
270
271 for (i = 0; i < count; i++) {
272 ret = crypto_register_aead(&algs[i]);
273 if (ret)
274 goto err;
275 }
276
277 return 0;
278
279err:
280 for (--i; i >= 0; --i)
281 crypto_unregister_aead(&algs[i]);
282
283 return ret;
284}
285EXPORT_SYMBOL_GPL(crypto_register_aeads);
286
287void crypto_unregister_aeads(struct aead_alg *algs, int count)
288{
289 int i;
290
291 for (i = count - 1; i >= 0; --i)
292 crypto_unregister_aead(&algs[i]);
293}
294EXPORT_SYMBOL_GPL(crypto_unregister_aeads);
295
296int aead_register_instance(struct crypto_template *tmpl,
297 struct aead_instance *inst)
298{
299 int err;
300
301 if (WARN_ON(!inst->free))
302 return -EINVAL;
303
304 err = aead_prepare_alg(&inst->alg);
305 if (err)
306 return err;
307
308 return crypto_register_instance(tmpl, aead_crypto_instance(inst));
309}
310EXPORT_SYMBOL_GPL(aead_register_instance);
311
312MODULE_LICENSE("GPL");
313MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");