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/geniv.h>
11 #include <crypto/internal/rng.h>
12 #include <crypto/null.h>
13 #include <crypto/scatterwalk.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/slab.h>
20 #include <linux/seq_file.h>
21 #include <linux/cryptouser.h>
22 #include <linux/compiler.h>
23 #include <net/netlink.h>
24
25 #include "internal.h"
26
setkey_unaligned(struct crypto_aead * tfm,const u8 * key,unsigned int keylen)27 static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
28 unsigned int keylen)
29 {
30 unsigned long alignmask = crypto_aead_alignmask(tfm);
31 int ret;
32 u8 *buffer, *alignbuffer;
33 unsigned long absize;
34
35 absize = keylen + alignmask;
36 buffer = kmalloc(absize, GFP_ATOMIC);
37 if (!buffer)
38 return -ENOMEM;
39
40 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
41 memcpy(alignbuffer, key, keylen);
42 ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
43 memset(alignbuffer, 0, keylen);
44 kfree(buffer);
45 return ret;
46 }
47
crypto_aead_setkey(struct crypto_aead * tfm,const u8 * key,unsigned int keylen)48 int crypto_aead_setkey(struct crypto_aead *tfm,
49 const u8 *key, unsigned int keylen)
50 {
51 unsigned long alignmask = crypto_aead_alignmask(tfm);
52 int err;
53
54 if ((unsigned long)key & alignmask)
55 err = setkey_unaligned(tfm, key, keylen);
56 else
57 err = crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
58
59 if (unlikely(err)) {
60 crypto_aead_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
61 return err;
62 }
63
64 crypto_aead_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
65 return 0;
66 }
67 EXPORT_SYMBOL_GPL(crypto_aead_setkey);
68
crypto_aead_setauthsize(struct crypto_aead * tfm,unsigned int authsize)69 int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
70 {
71 int err;
72
73 if ((!authsize && crypto_aead_maxauthsize(tfm)) ||
74 authsize > crypto_aead_maxauthsize(tfm))
75 return -EINVAL;
76
77 if (crypto_aead_alg(tfm)->setauthsize) {
78 err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize);
79 if (err)
80 return err;
81 }
82
83 tfm->authsize = authsize;
84 return 0;
85 }
86 EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
87
crypto_aead_encrypt(struct aead_request * req)88 int crypto_aead_encrypt(struct aead_request *req)
89 {
90 struct crypto_aead *aead = crypto_aead_reqtfm(req);
91 struct crypto_alg *alg = aead->base.__crt_alg;
92 unsigned int cryptlen = req->cryptlen;
93 int ret;
94
95 crypto_stats_get(alg);
96 if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
97 ret = -ENOKEY;
98 else
99 ret = crypto_aead_alg(aead)->encrypt(req);
100 crypto_stats_aead_encrypt(cryptlen, alg, ret);
101 return ret;
102 }
103 EXPORT_SYMBOL_GPL(crypto_aead_encrypt);
104
crypto_aead_decrypt(struct aead_request * req)105 int crypto_aead_decrypt(struct aead_request *req)
106 {
107 struct crypto_aead *aead = crypto_aead_reqtfm(req);
108 struct crypto_alg *alg = aead->base.__crt_alg;
109 unsigned int cryptlen = req->cryptlen;
110 int ret;
111
112 crypto_stats_get(alg);
113 if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
114 ret = -ENOKEY;
115 else if (req->cryptlen < crypto_aead_authsize(aead))
116 ret = -EINVAL;
117 else
118 ret = crypto_aead_alg(aead)->decrypt(req);
119 crypto_stats_aead_decrypt(cryptlen, alg, ret);
120 return ret;
121 }
122 EXPORT_SYMBOL_GPL(crypto_aead_decrypt);
123
crypto_aead_exit_tfm(struct crypto_tfm * tfm)124 static void crypto_aead_exit_tfm(struct crypto_tfm *tfm)
125 {
126 struct crypto_aead *aead = __crypto_aead_cast(tfm);
127 struct aead_alg *alg = crypto_aead_alg(aead);
128
129 alg->exit(aead);
130 }
131
crypto_aead_init_tfm(struct crypto_tfm * tfm)132 static int crypto_aead_init_tfm(struct crypto_tfm *tfm)
133 {
134 struct crypto_aead *aead = __crypto_aead_cast(tfm);
135 struct aead_alg *alg = crypto_aead_alg(aead);
136
137 crypto_aead_set_flags(aead, CRYPTO_TFM_NEED_KEY);
138
139 aead->authsize = alg->maxauthsize;
140
141 if (alg->exit)
142 aead->base.exit = crypto_aead_exit_tfm;
143
144 if (alg->init)
145 return alg->init(aead);
146
147 return 0;
148 }
149
150 #ifdef CONFIG_NET
crypto_aead_report(struct sk_buff * skb,struct crypto_alg * alg)151 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
152 {
153 struct crypto_report_aead raead;
154 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
155
156 memset(&raead, 0, sizeof(raead));
157
158 strscpy(raead.type, "aead", sizeof(raead.type));
159 strscpy(raead.geniv, "<none>", sizeof(raead.geniv));
160
161 raead.blocksize = alg->cra_blocksize;
162 raead.maxauthsize = aead->maxauthsize;
163 raead.ivsize = aead->ivsize;
164
165 return nla_put(skb, CRYPTOCFGA_REPORT_AEAD, sizeof(raead), &raead);
166 }
167 #else
crypto_aead_report(struct sk_buff * skb,struct crypto_alg * alg)168 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
169 {
170 return -ENOSYS;
171 }
172 #endif
173
174 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
175 __maybe_unused;
crypto_aead_show(struct seq_file * m,struct crypto_alg * alg)176 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
177 {
178 struct aead_alg *aead = container_of(alg, struct aead_alg, base);
179
180 seq_printf(m, "type : aead\n");
181 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
182 "yes" : "no");
183 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
184 seq_printf(m, "ivsize : %u\n", aead->ivsize);
185 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
186 seq_printf(m, "geniv : <none>\n");
187 }
188
crypto_aead_free_instance(struct crypto_instance * inst)189 static void crypto_aead_free_instance(struct crypto_instance *inst)
190 {
191 struct aead_instance *aead = aead_instance(inst);
192
193 if (!aead->free) {
194 inst->tmpl->free(inst);
195 return;
196 }
197
198 aead->free(aead);
199 }
200
201 static const struct crypto_type crypto_aead_type = {
202 .extsize = crypto_alg_extsize,
203 .init_tfm = crypto_aead_init_tfm,
204 .free = crypto_aead_free_instance,
205 #ifdef CONFIG_PROC_FS
206 .show = crypto_aead_show,
207 #endif
208 .report = crypto_aead_report,
209 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
210 .maskset = CRYPTO_ALG_TYPE_MASK,
211 .type = CRYPTO_ALG_TYPE_AEAD,
212 .tfmsize = offsetof(struct crypto_aead, base),
213 };
214
aead_geniv_setkey(struct crypto_aead * tfm,const u8 * key,unsigned int keylen)215 static int aead_geniv_setkey(struct crypto_aead *tfm,
216 const u8 *key, unsigned int keylen)
217 {
218 struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
219
220 return crypto_aead_setkey(ctx->child, key, keylen);
221 }
222
aead_geniv_setauthsize(struct crypto_aead * tfm,unsigned int authsize)223 static int aead_geniv_setauthsize(struct crypto_aead *tfm,
224 unsigned int authsize)
225 {
226 struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
227
228 return crypto_aead_setauthsize(ctx->child, authsize);
229 }
230
aead_geniv_alloc(struct crypto_template * tmpl,struct rtattr ** tb,u32 type,u32 mask)231 struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,
232 struct rtattr **tb, u32 type, u32 mask)
233 {
234 const char *name;
235 struct crypto_aead_spawn *spawn;
236 struct crypto_attr_type *algt;
237 struct aead_instance *inst;
238 struct aead_alg *alg;
239 unsigned int ivsize;
240 unsigned int maxauthsize;
241 int err;
242
243 algt = crypto_get_attr_type(tb);
244 if (IS_ERR(algt))
245 return ERR_CAST(algt);
246
247 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
248 return ERR_PTR(-EINVAL);
249
250 name = crypto_attr_alg_name(tb[1]);
251 if (IS_ERR(name))
252 return ERR_CAST(name);
253
254 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
255 if (!inst)
256 return ERR_PTR(-ENOMEM);
257
258 spawn = aead_instance_ctx(inst);
259
260 /* Ignore async algorithms if necessary. */
261 mask |= crypto_requires_sync(algt->type, algt->mask);
262
263 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
264 err = crypto_grab_aead(spawn, name, type, mask);
265 if (err)
266 goto err_free_inst;
267
268 alg = crypto_spawn_aead_alg(spawn);
269
270 ivsize = crypto_aead_alg_ivsize(alg);
271 maxauthsize = crypto_aead_alg_maxauthsize(alg);
272
273 err = -EINVAL;
274 if (ivsize < sizeof(u64))
275 goto err_drop_alg;
276
277 err = -ENAMETOOLONG;
278 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
279 "%s(%s)", tmpl->name, alg->base.cra_name) >=
280 CRYPTO_MAX_ALG_NAME)
281 goto err_drop_alg;
282 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
283 "%s(%s)", tmpl->name, alg->base.cra_driver_name) >=
284 CRYPTO_MAX_ALG_NAME)
285 goto err_drop_alg;
286
287 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
288 inst->alg.base.cra_priority = alg->base.cra_priority;
289 inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
290 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
291 inst->alg.base.cra_ctxsize = sizeof(struct aead_geniv_ctx);
292
293 inst->alg.setkey = aead_geniv_setkey;
294 inst->alg.setauthsize = aead_geniv_setauthsize;
295
296 inst->alg.ivsize = ivsize;
297 inst->alg.maxauthsize = maxauthsize;
298
299 out:
300 return inst;
301
302 err_drop_alg:
303 crypto_drop_aead(spawn);
304 err_free_inst:
305 kfree(inst);
306 inst = ERR_PTR(err);
307 goto out;
308 }
309 EXPORT_SYMBOL_GPL(aead_geniv_alloc);
310
aead_geniv_free(struct aead_instance * inst)311 void aead_geniv_free(struct aead_instance *inst)
312 {
313 crypto_drop_aead(aead_instance_ctx(inst));
314 kfree(inst);
315 }
316 EXPORT_SYMBOL_GPL(aead_geniv_free);
317
aead_init_geniv(struct crypto_aead * aead)318 int aead_init_geniv(struct crypto_aead *aead)
319 {
320 struct aead_geniv_ctx *ctx = crypto_aead_ctx(aead);
321 struct aead_instance *inst = aead_alg_instance(aead);
322 struct crypto_aead *child;
323 int err;
324
325 spin_lock_init(&ctx->lock);
326
327 err = crypto_get_default_rng();
328 if (err)
329 goto out;
330
331 err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt,
332 crypto_aead_ivsize(aead));
333 crypto_put_default_rng();
334 if (err)
335 goto out;
336
337 ctx->sknull = crypto_get_default_null_skcipher();
338 err = PTR_ERR(ctx->sknull);
339 if (IS_ERR(ctx->sknull))
340 goto out;
341
342 child = crypto_spawn_aead(aead_instance_ctx(inst));
343 err = PTR_ERR(child);
344 if (IS_ERR(child))
345 goto drop_null;
346
347 ctx->child = child;
348 crypto_aead_set_reqsize(aead, crypto_aead_reqsize(child) +
349 sizeof(struct aead_request));
350
351 err = 0;
352
353 out:
354 return err;
355
356 drop_null:
357 crypto_put_default_null_skcipher();
358 goto out;
359 }
360 EXPORT_SYMBOL_GPL(aead_init_geniv);
361
aead_exit_geniv(struct crypto_aead * tfm)362 void aead_exit_geniv(struct crypto_aead *tfm)
363 {
364 struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
365
366 crypto_free_aead(ctx->child);
367 crypto_put_default_null_skcipher();
368 }
369 EXPORT_SYMBOL_GPL(aead_exit_geniv);
370
crypto_grab_aead(struct crypto_aead_spawn * spawn,const char * name,u32 type,u32 mask)371 int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
372 u32 type, u32 mask)
373 {
374 spawn->base.frontend = &crypto_aead_type;
375 return crypto_grab_spawn(&spawn->base, name, type, mask);
376 }
377 EXPORT_SYMBOL_GPL(crypto_grab_aead);
378
crypto_alloc_aead(const char * alg_name,u32 type,u32 mask)379 struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
380 {
381 return crypto_alloc_tfm(alg_name, &crypto_aead_type, type, mask);
382 }
383 EXPORT_SYMBOL_GPL(crypto_alloc_aead);
384
aead_prepare_alg(struct aead_alg * alg)385 static int aead_prepare_alg(struct aead_alg *alg)
386 {
387 struct crypto_alg *base = &alg->base;
388
389 if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) >
390 PAGE_SIZE / 8)
391 return -EINVAL;
392
393 if (!alg->chunksize)
394 alg->chunksize = base->cra_blocksize;
395
396 base->cra_type = &crypto_aead_type;
397 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
398 base->cra_flags |= CRYPTO_ALG_TYPE_AEAD;
399
400 return 0;
401 }
402
crypto_register_aead(struct aead_alg * alg)403 int crypto_register_aead(struct aead_alg *alg)
404 {
405 struct crypto_alg *base = &alg->base;
406 int err;
407
408 err = aead_prepare_alg(alg);
409 if (err)
410 return err;
411
412 return crypto_register_alg(base);
413 }
414 EXPORT_SYMBOL_GPL(crypto_register_aead);
415
crypto_unregister_aead(struct aead_alg * alg)416 void crypto_unregister_aead(struct aead_alg *alg)
417 {
418 crypto_unregister_alg(&alg->base);
419 }
420 EXPORT_SYMBOL_GPL(crypto_unregister_aead);
421
crypto_register_aeads(struct aead_alg * algs,int count)422 int crypto_register_aeads(struct aead_alg *algs, int count)
423 {
424 int i, ret;
425
426 for (i = 0; i < count; i++) {
427 ret = crypto_register_aead(&algs[i]);
428 if (ret)
429 goto err;
430 }
431
432 return 0;
433
434 err:
435 for (--i; i >= 0; --i)
436 crypto_unregister_aead(&algs[i]);
437
438 return ret;
439 }
440 EXPORT_SYMBOL_GPL(crypto_register_aeads);
441
crypto_unregister_aeads(struct aead_alg * algs,int count)442 void crypto_unregister_aeads(struct aead_alg *algs, int count)
443 {
444 int i;
445
446 for (i = count - 1; i >= 0; --i)
447 crypto_unregister_aead(&algs[i]);
448 }
449 EXPORT_SYMBOL_GPL(crypto_unregister_aeads);
450
aead_register_instance(struct crypto_template * tmpl,struct aead_instance * inst)451 int aead_register_instance(struct crypto_template *tmpl,
452 struct aead_instance *inst)
453 {
454 int err;
455
456 err = aead_prepare_alg(&inst->alg);
457 if (err)
458 return err;
459
460 return crypto_register_instance(tmpl, aead_crypto_instance(inst));
461 }
462 EXPORT_SYMBOL_GPL(aead_register_instance);
463
464 MODULE_LICENSE("GPL");
465 MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
466
