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
23 static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
24 unsigned int keylen)
25 {
26 unsigned long alignmask = crypto_aead_alignmask(tfm);
27 int ret;
28 u8 *buffer, *alignbuffer;
29 unsigned long absize;
30
31 absize = keylen + alignmask;
32 buffer = kmalloc(absize, GFP_ATOMIC);
33 if (!buffer)
34 return -ENOMEM;
35
36 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
37 memcpy(alignbuffer, key, keylen);
38 ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
39 kfree_sensitive(buffer);
40 return ret;
41 }
42
43 int crypto_aead_setkey(struct crypto_aead *tfm,
44 const u8 *key, unsigned int keylen)
45 {
46 unsigned long alignmask = crypto_aead_alignmask(tfm);
47 int err;
48
49 if ((unsigned long)key & alignmask)
50 err = setkey_unaligned(tfm, key, keylen);
51 else
52 err = crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
53
54 if (unlikely(err)) {
55 crypto_aead_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
56 return err;
57 }
58
59 crypto_aead_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
60 return 0;
61 }
62 EXPORT_SYMBOL_GPL(crypto_aead_setkey);
63
64 int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
65 {
66 int err;
67
68 if ((!authsize && crypto_aead_maxauthsize(tfm)) ||
69 authsize > crypto_aead_maxauthsize(tfm))
70 return -EINVAL;
71
72 if (crypto_aead_alg(tfm)->setauthsize) {
73 err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize);
74 if (err)
75 return err;
76 }
77
78 tfm->authsize = authsize;
79 return 0;
80 }
81 EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
82
83 int crypto_aead_encrypt(struct aead_request *req)
84 {
85 struct crypto_aead *aead = crypto_aead_reqtfm(req);
86
87 if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
88 return -ENOKEY;
89
90 return crypto_aead_alg(aead)->encrypt(req);
91 }
92 EXPORT_SYMBOL_GPL(crypto_aead_encrypt);
93
94 int crypto_aead_decrypt(struct aead_request *req)
95 {
96 struct crypto_aead *aead = crypto_aead_reqtfm(req);
97
98 if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
99 return -ENOKEY;
100
101 if (req->cryptlen < crypto_aead_authsize(aead))
102 return -EINVAL;
103
104 return crypto_aead_alg(aead)->decrypt(req);
105 }
106 EXPORT_SYMBOL_GPL(crypto_aead_decrypt);
107
108 static void crypto_aead_exit_tfm(struct crypto_tfm *tfm)
109 {
110 struct crypto_aead *aead = __crypto_aead_cast(tfm);
111 struct aead_alg *alg = crypto_aead_alg(aead);
112
113 alg->exit(aead);
114 }
115
116 static int crypto_aead_init_tfm(struct crypto_tfm *tfm)
117 {
118 struct crypto_aead *aead = __crypto_aead_cast(tfm);
119 struct aead_alg *alg = crypto_aead_alg(aead);
120
121 crypto_aead_set_flags(aead, CRYPTO_TFM_NEED_KEY);
122
123 aead->authsize = alg->maxauthsize;
124
125 if (alg->exit)
126 aead->base.exit = crypto_aead_exit_tfm;
127
128 if (alg->init)
129 return alg->init(aead);
130
131 return 0;
132 }
133
134 static int __maybe_unused crypto_aead_report(
135 struct sk_buff *skb, struct crypto_alg *alg)
136 {
137 struct crypto_report_aead raead;
138 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
139
140 memset(&raead, 0, sizeof(raead));
141
142 strscpy(raead.type, "aead", sizeof(raead.type));
143 strscpy(raead.geniv, "<none>", sizeof(raead.geniv));
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
152 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
153 __maybe_unused;
154 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
155 {
156 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
157
158 seq_printf(m, "type : aead\n");
159 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
160 "yes" : "no");
161 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
162 seq_printf(m, "ivsize : %u\n", aead->ivsize);
163 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
164 seq_printf(m, "geniv : <none>\n");
165 }
166
167 static void crypto_aead_free_instance(struct crypto_instance *inst)
168 {
169 struct aead_instance *aead = aead_instance(inst);
170
171 aead->free(aead);
172 }
173
174 static const struct crypto_type crypto_aead_type = {
175 .extsize = crypto_alg_extsize,
176 .init_tfm = crypto_aead_init_tfm,
177 .free = crypto_aead_free_instance,
178 #ifdef CONFIG_PROC_FS
179 .show = crypto_aead_show,
180 #endif
181 #if IS_ENABLED(CONFIG_CRYPTO_USER)
182 .report = crypto_aead_report,
183 #endif
184 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
185 .maskset = CRYPTO_ALG_TYPE_MASK,
186 .type = CRYPTO_ALG_TYPE_AEAD,
187 .tfmsize = offsetof(struct crypto_aead, base),
188 };
189
190 int 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 }
197 EXPORT_SYMBOL_GPL(crypto_grab_aead);
198
199 struct 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 }
203 EXPORT_SYMBOL_GPL(crypto_alloc_aead);
204
205 int crypto_has_aead(const char *alg_name, u32 type, u32 mask)
206 {
207 return crypto_type_has_alg(alg_name, &crypto_aead_type, type, mask);
208 }
209 EXPORT_SYMBOL_GPL(crypto_has_aead);
210
211 static int aead_prepare_alg(struct aead_alg *alg)
212 {
213 struct crypto_alg *base = &alg->base;
214
215 if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) >
216 PAGE_SIZE / 8)
217 return -EINVAL;
218
219 if (!alg->chunksize)
220 alg->chunksize = base->cra_blocksize;
221
222 base->cra_type = &crypto_aead_type;
223 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
224 base->cra_flags |= CRYPTO_ALG_TYPE_AEAD;
225
226 return 0;
227 }
228
229 int crypto_register_aead(struct aead_alg *alg)
230 {
231 struct crypto_alg *base = &alg->base;
232 int err;
233
234 err = aead_prepare_alg(alg);
235 if (err)
236 return err;
237
238 return crypto_register_alg(base);
239 }
240 EXPORT_SYMBOL_GPL(crypto_register_aead);
241
242 void crypto_unregister_aead(struct aead_alg *alg)
243 {
244 crypto_unregister_alg(&alg->base);
245 }
246 EXPORT_SYMBOL_GPL(crypto_unregister_aead);
247
248 int crypto_register_aeads(struct aead_alg *algs, int count)
249 {
250 int i, ret;
251
252 for (i = 0; i < count; i++) {
253 ret = crypto_register_aead(&algs[i]);
254 if (ret)
255 goto err;
256 }
257
258 return 0;
259
260 err:
261 for (--i; i >= 0; --i)
262 crypto_unregister_aead(&algs[i]);
263
264 return ret;
265 }
266 EXPORT_SYMBOL_GPL(crypto_register_aeads);
267
268 void crypto_unregister_aeads(struct aead_alg *algs, int count)
269 {
270 int i;
271
272 for (i = count - 1; i >= 0; --i)
273 crypto_unregister_aead(&algs[i]);
274 }
275 EXPORT_SYMBOL_GPL(crypto_unregister_aeads);
276
277 int aead_register_instance(struct crypto_template *tmpl,
278 struct aead_instance *inst)
279 {
280 int err;
281
282 if (WARN_ON(!inst->free))
283 return -EINVAL;
284
285 err = aead_prepare_alg(&inst->alg);
286 if (err)
287 return err;
288
289 return crypto_register_instance(tmpl, aead_crypto_instance(inst));
290 }
291 EXPORT_SYMBOL_GPL(aead_register_instance);
292
293 MODULE_LICENSE("GPL");
294 MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
295
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