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 <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(to: alignbuffer, from: key, len: keylen);
39 ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
40 kfree_sensitive(objp: 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(aead: tfm)) ||
70 authsize > crypto_aead_maxauthsize(aead: 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(tfm: aead) & CRYPTO_TFM_NEED_KEY)
89 return -ENOKEY;
90
91 return crypto_aead_alg(tfm: 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(tfm: aead) & CRYPTO_TFM_NEED_KEY)
100 return -ENOKEY;
101
102 if (req->cryptlen < crypto_aead_authsize(tfm: aead))
103 return -EINVAL;
104
105 return crypto_aead_alg(tfm: 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(tfm: 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(tfm: aead);
121
122 crypto_aead_set_flags(tfm: aead, CRYPTO_TFM_NEED_KEY);
123
124 aead->authsize = alg->maxauthsize;
125
126 if (alg->exit)
127 aead->base.exit = crypto_aead_exit_tfm;
128
129 if (alg->init)
130 return alg->init(aead);
131
132 return 0;
133}
134
135static int __maybe_unused crypto_aead_report(
136 struct sk_buff *skb, struct crypto_alg *alg)
137{
138 struct crypto_report_aead raead;
139 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
140
141 memset(s: &raead, c: 0, n: sizeof(raead));
142
143 strscpy(raead.type, "aead", sizeof(raead.type));
144 strscpy(raead.geniv, "<none>", sizeof(raead.geniv));
145
146 raead.blocksize = alg->cra_blocksize;
147 raead.maxauthsize = aead->maxauthsize;
148 raead.ivsize = aead->ivsize;
149
150 return nla_put(skb, attrtype: CRYPTOCFGA_REPORT_AEAD, attrlen: sizeof(raead), data: &raead);
151}
152
153static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
154 __maybe_unused;
155static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
156{
157 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
158
159 seq_printf(m, fmt: "type : aead\n");
160 seq_printf(m, fmt: "async : %s\n",
161 str_yes_no(v: alg->cra_flags & CRYPTO_ALG_ASYNC));
162 seq_printf(m, fmt: "blocksize : %u\n", alg->cra_blocksize);
163 seq_printf(m, fmt: "ivsize : %u\n", aead->ivsize);
164 seq_printf(m, fmt: "maxauthsize : %u\n", aead->maxauthsize);
165 seq_printf(m, fmt: "geniv : <none>\n");
166}
167
168static void crypto_aead_free_instance(struct crypto_instance *inst)
169{
170 struct aead_instance *aead = aead_instance(inst);
171
172 aead->free(aead);
173}
174
175static const struct crypto_type crypto_aead_type = {
176 .extsize = crypto_alg_extsize,
177 .init_tfm = crypto_aead_init_tfm,
178 .free = crypto_aead_free_instance,
179#ifdef CONFIG_PROC_FS
180 .show = crypto_aead_show,
181#endif
182#if IS_ENABLED(CONFIG_CRYPTO_USER)
183 .report = crypto_aead_report,
184#endif
185 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
186 .maskset = CRYPTO_ALG_TYPE_MASK,
187 .type = CRYPTO_ALG_TYPE_AEAD,
188 .tfmsize = offsetof(struct crypto_aead, base),
189 .algsize = offsetof(struct aead_alg, base),
190};
191
192int crypto_grab_aead(struct crypto_aead_spawn *spawn,
193 struct crypto_instance *inst,
194 const char *name, u32 type, u32 mask)
195{
196 spawn->base.frontend = &crypto_aead_type;
197 return crypto_grab_spawn(spawn: &spawn->base, inst, name, type, mask);
198}
199EXPORT_SYMBOL_GPL(crypto_grab_aead);
200
201struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
202{
203 return crypto_alloc_tfm(alg_name, frontend: &crypto_aead_type, type, mask);
204}
205EXPORT_SYMBOL_GPL(crypto_alloc_aead);
206
207int crypto_has_aead(const char *alg_name, u32 type, u32 mask)
208{
209 return crypto_type_has_alg(name: alg_name, frontend: &crypto_aead_type, type, mask);
210}
211EXPORT_SYMBOL_GPL(crypto_has_aead);
212
213static int aead_prepare_alg(struct aead_alg *alg)
214{
215 struct crypto_alg *base = &alg->base;
216
217 if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) >
218 PAGE_SIZE / 8)
219 return -EINVAL;
220
221 if (!alg->chunksize)
222 alg->chunksize = base->cra_blocksize;
223
224 base->cra_type = &crypto_aead_type;
225 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
226 base->cra_flags |= CRYPTO_ALG_TYPE_AEAD;
227
228 return 0;
229}
230
231int crypto_register_aead(struct aead_alg *alg)
232{
233 struct crypto_alg *base = &alg->base;
234 int err;
235
236 err = aead_prepare_alg(alg);
237 if (err)
238 return err;
239
240 return crypto_register_alg(alg: base);
241}
242EXPORT_SYMBOL_GPL(crypto_register_aead);
243
244void crypto_unregister_aead(struct aead_alg *alg)
245{
246 crypto_unregister_alg(alg: &alg->base);
247}
248EXPORT_SYMBOL_GPL(crypto_unregister_aead);
249
250int crypto_register_aeads(struct aead_alg *algs, int count)
251{
252 int i, ret;
253
254 for (i = 0; i < count; i++) {
255 ret = crypto_register_aead(&algs[i]);
256 if (ret)
257 goto err;
258 }
259
260 return 0;
261
262err:
263 for (--i; i >= 0; --i)
264 crypto_unregister_aead(&algs[i]);
265
266 return ret;
267}
268EXPORT_SYMBOL_GPL(crypto_register_aeads);
269
270void crypto_unregister_aeads(struct aead_alg *algs, int count)
271{
272 int i;
273
274 for (i = count - 1; i >= 0; --i)
275 crypto_unregister_aead(&algs[i]);
276}
277EXPORT_SYMBOL_GPL(crypto_unregister_aeads);
278
279int aead_register_instance(struct crypto_template *tmpl,
280 struct aead_instance *inst)
281{
282 int err;
283
284 if (WARN_ON(!inst->free))
285 return -EINVAL;
286
287 err = aead_prepare_alg(alg: &inst->alg);
288 if (err)
289 return err;
290
291 return crypto_register_instance(tmpl, inst: aead_crypto_instance(inst));
292}
293EXPORT_SYMBOL_GPL(aead_register_instance);
294
295MODULE_LICENSE("GPL");
296MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
297