1 /*
2 * AEAD: Authenticated Encryption with Associated Data
3 *
4 * This file provides API support for AEAD algorithms.
5 *
6 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
11 * any later version.
12 *
13 */
14
15 #include <crypto/internal/aead.h>
16 #include <linux/err.h>
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <linux/seq_file.h>
24 #include <linux/cryptouser.h>
25 #include <net/netlink.h>
26
27 #include "internal.h"
28
setkey_unaligned(struct crypto_aead * tfm,const u8 * key,unsigned int keylen)29 static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
30 unsigned int keylen)
31 {
32 struct aead_alg *aead = crypto_aead_alg(tfm);
33 unsigned long alignmask = crypto_aead_alignmask(tfm);
34 int ret;
35 u8 *buffer, *alignbuffer;
36 unsigned long absize;
37
38 absize = keylen + alignmask;
39 buffer = kmalloc(absize, GFP_ATOMIC);
40 if (!buffer)
41 return -ENOMEM;
42
43 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
44 memcpy(alignbuffer, key, keylen);
45 ret = aead->setkey(tfm, alignbuffer, keylen);
46 memset(alignbuffer, 0, keylen);
47 kfree(buffer);
48 return ret;
49 }
50
setkey(struct crypto_aead * tfm,const u8 * key,unsigned int keylen)51 static int setkey(struct crypto_aead *tfm, const u8 *key, unsigned int keylen)
52 {
53 struct aead_alg *aead = crypto_aead_alg(tfm);
54 unsigned long alignmask = crypto_aead_alignmask(tfm);
55
56 if ((unsigned long)key & alignmask)
57 return setkey_unaligned(tfm, key, keylen);
58
59 return aead->setkey(tfm, key, keylen);
60 }
61
crypto_aead_setauthsize(struct crypto_aead * tfm,unsigned int authsize)62 int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
63 {
64 struct aead_tfm *crt = crypto_aead_crt(tfm);
65 int err;
66
67 if (authsize > crypto_aead_alg(tfm)->maxauthsize)
68 return -EINVAL;
69
70 if (crypto_aead_alg(tfm)->setauthsize) {
71 err = crypto_aead_alg(tfm)->setauthsize(crt->base, authsize);
72 if (err)
73 return err;
74 }
75
76 crypto_aead_crt(crt->base)->authsize = authsize;
77 crt->authsize = authsize;
78 return 0;
79 }
80 EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
81
crypto_aead_ctxsize(struct crypto_alg * alg,u32 type,u32 mask)82 static unsigned int crypto_aead_ctxsize(struct crypto_alg *alg, u32 type,
83 u32 mask)
84 {
85 return alg->cra_ctxsize;
86 }
87
no_givcrypt(struct aead_givcrypt_request * req)88 static int no_givcrypt(struct aead_givcrypt_request *req)
89 {
90 return -ENOSYS;
91 }
92
crypto_init_aead_ops(struct crypto_tfm * tfm,u32 type,u32 mask)93 static int crypto_init_aead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
94 {
95 struct aead_alg *alg = &tfm->__crt_alg->cra_aead;
96 struct aead_tfm *crt = &tfm->crt_aead;
97
98 if (max(alg->maxauthsize, alg->ivsize) > PAGE_SIZE / 8)
99 return -EINVAL;
100
101 crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
102 alg->setkey : setkey;
103 crt->encrypt = alg->encrypt;
104 crt->decrypt = alg->decrypt;
105 crt->givencrypt = alg->givencrypt ?: no_givcrypt;
106 crt->givdecrypt = alg->givdecrypt ?: no_givcrypt;
107 crt->base = __crypto_aead_cast(tfm);
108 crt->ivsize = alg->ivsize;
109 crt->authsize = alg->maxauthsize;
110
111 return 0;
112 }
113
114 #ifdef CONFIG_NET
crypto_aead_report(struct sk_buff * skb,struct crypto_alg * alg)115 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
116 {
117 struct crypto_report_aead raead;
118 struct aead_alg *aead = &alg->cra_aead;
119
120 strncpy(raead.type, "aead", sizeof(raead.type));
121 strncpy(raead.geniv, aead->geniv ?: "<built-in>", sizeof(raead.geniv));
122
123 raead.blocksize = alg->cra_blocksize;
124 raead.maxauthsize = aead->maxauthsize;
125 raead.ivsize = aead->ivsize;
126
127 if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD,
128 sizeof(struct crypto_report_aead), &raead))
129 goto nla_put_failure;
130 return 0;
131
132 nla_put_failure:
133 return -EMSGSIZE;
134 }
135 #else
crypto_aead_report(struct sk_buff * skb,struct crypto_alg * alg)136 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
137 {
138 return -ENOSYS;
139 }
140 #endif
141
142 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
143 __attribute__ ((unused));
crypto_aead_show(struct seq_file * m,struct crypto_alg * alg)144 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
145 {
146 struct aead_alg *aead = &alg->cra_aead;
147
148 seq_printf(m, "type : aead\n");
149 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
150 "yes" : "no");
151 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
152 seq_printf(m, "ivsize : %u\n", aead->ivsize);
153 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
154 seq_printf(m, "geniv : %s\n", aead->geniv ?: "<built-in>");
155 }
156
157 const struct crypto_type crypto_aead_type = {
158 .ctxsize = crypto_aead_ctxsize,
159 .init = crypto_init_aead_ops,
160 #ifdef CONFIG_PROC_FS
161 .show = crypto_aead_show,
162 #endif
163 .report = crypto_aead_report,
164 };
165 EXPORT_SYMBOL_GPL(crypto_aead_type);
166
aead_null_givencrypt(struct aead_givcrypt_request * req)167 static int aead_null_givencrypt(struct aead_givcrypt_request *req)
168 {
169 return crypto_aead_encrypt(&req->areq);
170 }
171
aead_null_givdecrypt(struct aead_givcrypt_request * req)172 static int aead_null_givdecrypt(struct aead_givcrypt_request *req)
173 {
174 return crypto_aead_decrypt(&req->areq);
175 }
176
crypto_init_nivaead_ops(struct crypto_tfm * tfm,u32 type,u32 mask)177 static int crypto_init_nivaead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
178 {
179 struct aead_alg *alg = &tfm->__crt_alg->cra_aead;
180 struct aead_tfm *crt = &tfm->crt_aead;
181
182 if (max(alg->maxauthsize, alg->ivsize) > PAGE_SIZE / 8)
183 return -EINVAL;
184
185 crt->setkey = setkey;
186 crt->encrypt = alg->encrypt;
187 crt->decrypt = alg->decrypt;
188 if (!alg->ivsize) {
189 crt->givencrypt = aead_null_givencrypt;
190 crt->givdecrypt = aead_null_givdecrypt;
191 }
192 crt->base = __crypto_aead_cast(tfm);
193 crt->ivsize = alg->ivsize;
194 crt->authsize = alg->maxauthsize;
195
196 return 0;
197 }
198
199 #ifdef CONFIG_NET
crypto_nivaead_report(struct sk_buff * skb,struct crypto_alg * alg)200 static int crypto_nivaead_report(struct sk_buff *skb, struct crypto_alg *alg)
201 {
202 struct crypto_report_aead raead;
203 struct aead_alg *aead = &alg->cra_aead;
204
205 strncpy(raead.type, "nivaead", sizeof(raead.type));
206 strncpy(raead.geniv, aead->geniv, sizeof(raead.geniv));
207
208 raead.blocksize = alg->cra_blocksize;
209 raead.maxauthsize = aead->maxauthsize;
210 raead.ivsize = aead->ivsize;
211
212 if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD,
213 sizeof(struct crypto_report_aead), &raead))
214 goto nla_put_failure;
215 return 0;
216
217 nla_put_failure:
218 return -EMSGSIZE;
219 }
220 #else
crypto_nivaead_report(struct sk_buff * skb,struct crypto_alg * alg)221 static int crypto_nivaead_report(struct sk_buff *skb, struct crypto_alg *alg)
222 {
223 return -ENOSYS;
224 }
225 #endif
226
227
228 static void crypto_nivaead_show(struct seq_file *m, struct crypto_alg *alg)
229 __attribute__ ((unused));
crypto_nivaead_show(struct seq_file * m,struct crypto_alg * alg)230 static void crypto_nivaead_show(struct seq_file *m, struct crypto_alg *alg)
231 {
232 struct aead_alg *aead = &alg->cra_aead;
233
234 seq_printf(m, "type : nivaead\n");
235 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
236 "yes" : "no");
237 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
238 seq_printf(m, "ivsize : %u\n", aead->ivsize);
239 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
240 seq_printf(m, "geniv : %s\n", aead->geniv);
241 }
242
243 const struct crypto_type crypto_nivaead_type = {
244 .ctxsize = crypto_aead_ctxsize,
245 .init = crypto_init_nivaead_ops,
246 #ifdef CONFIG_PROC_FS
247 .show = crypto_nivaead_show,
248 #endif
249 .report = crypto_nivaead_report,
250 };
251 EXPORT_SYMBOL_GPL(crypto_nivaead_type);
252
crypto_grab_nivaead(struct crypto_aead_spawn * spawn,const char * name,u32 type,u32 mask)253 static int crypto_grab_nivaead(struct crypto_aead_spawn *spawn,
254 const char *name, u32 type, u32 mask)
255 {
256 struct crypto_alg *alg;
257 int err;
258
259 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
260 type |= CRYPTO_ALG_TYPE_AEAD;
261 mask |= CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV;
262
263 alg = crypto_alg_mod_lookup(name, type, mask);
264 if (IS_ERR(alg))
265 return PTR_ERR(alg);
266
267 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
268 crypto_mod_put(alg);
269 return err;
270 }
271
aead_geniv_alloc(struct crypto_template * tmpl,struct rtattr ** tb,u32 type,u32 mask)272 struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
273 struct rtattr **tb, u32 type,
274 u32 mask)
275 {
276 const char *name;
277 struct crypto_aead_spawn *spawn;
278 struct crypto_attr_type *algt;
279 struct crypto_instance *inst;
280 struct crypto_alg *alg;
281 int err;
282
283 algt = crypto_get_attr_type(tb);
284 if (IS_ERR(algt))
285 return ERR_CAST(algt);
286
287 if ((algt->type ^ (CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV)) &
288 algt->mask)
289 return ERR_PTR(-EINVAL);
290
291 name = crypto_attr_alg_name(tb[1]);
292 if (IS_ERR(name))
293 return ERR_CAST(name);
294
295 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
296 if (!inst)
297 return ERR_PTR(-ENOMEM);
298
299 spawn = crypto_instance_ctx(inst);
300
301 /* Ignore async algorithms if necessary. */
302 mask |= crypto_requires_sync(algt->type, algt->mask);
303
304 crypto_set_aead_spawn(spawn, inst);
305 err = crypto_grab_nivaead(spawn, name, type, mask);
306 if (err)
307 goto err_free_inst;
308
309 alg = crypto_aead_spawn_alg(spawn);
310
311 err = -EINVAL;
312 if (!alg->cra_aead.ivsize)
313 goto err_drop_alg;
314
315 /*
316 * This is only true if we're constructing an algorithm with its
317 * default IV generator. For the default generator we elide the
318 * template name and double-check the IV generator.
319 */
320 if (algt->mask & CRYPTO_ALG_GENIV) {
321 if (strcmp(tmpl->name, alg->cra_aead.geniv))
322 goto err_drop_alg;
323
324 memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
325 memcpy(inst->alg.cra_driver_name, alg->cra_driver_name,
326 CRYPTO_MAX_ALG_NAME);
327 } else {
328 err = -ENAMETOOLONG;
329 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
330 "%s(%s)", tmpl->name, alg->cra_name) >=
331 CRYPTO_MAX_ALG_NAME)
332 goto err_drop_alg;
333 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
334 "%s(%s)", tmpl->name, alg->cra_driver_name) >=
335 CRYPTO_MAX_ALG_NAME)
336 goto err_drop_alg;
337 }
338
339 inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV;
340 inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
341 inst->alg.cra_priority = alg->cra_priority;
342 inst->alg.cra_blocksize = alg->cra_blocksize;
343 inst->alg.cra_alignmask = alg->cra_alignmask;
344 inst->alg.cra_type = &crypto_aead_type;
345
346 inst->alg.cra_aead.ivsize = alg->cra_aead.ivsize;
347 inst->alg.cra_aead.maxauthsize = alg->cra_aead.maxauthsize;
348 inst->alg.cra_aead.geniv = alg->cra_aead.geniv;
349
350 inst->alg.cra_aead.setkey = alg->cra_aead.setkey;
351 inst->alg.cra_aead.setauthsize = alg->cra_aead.setauthsize;
352 inst->alg.cra_aead.encrypt = alg->cra_aead.encrypt;
353 inst->alg.cra_aead.decrypt = alg->cra_aead.decrypt;
354
355 out:
356 return inst;
357
358 err_drop_alg:
359 crypto_drop_aead(spawn);
360 err_free_inst:
361 kfree(inst);
362 inst = ERR_PTR(err);
363 goto out;
364 }
365 EXPORT_SYMBOL_GPL(aead_geniv_alloc);
366
aead_geniv_free(struct crypto_instance * inst)367 void aead_geniv_free(struct crypto_instance *inst)
368 {
369 crypto_drop_aead(crypto_instance_ctx(inst));
370 kfree(inst);
371 }
372 EXPORT_SYMBOL_GPL(aead_geniv_free);
373
aead_geniv_init(struct crypto_tfm * tfm)374 int aead_geniv_init(struct crypto_tfm *tfm)
375 {
376 struct crypto_instance *inst = (void *)tfm->__crt_alg;
377 struct crypto_aead *aead;
378
379 aead = crypto_spawn_aead(crypto_instance_ctx(inst));
380 if (IS_ERR(aead))
381 return PTR_ERR(aead);
382
383 tfm->crt_aead.base = aead;
384 tfm->crt_aead.reqsize += crypto_aead_reqsize(aead);
385
386 return 0;
387 }
388 EXPORT_SYMBOL_GPL(aead_geniv_init);
389
aead_geniv_exit(struct crypto_tfm * tfm)390 void aead_geniv_exit(struct crypto_tfm *tfm)
391 {
392 crypto_free_aead(tfm->crt_aead.base);
393 }
394 EXPORT_SYMBOL_GPL(aead_geniv_exit);
395
crypto_nivaead_default(struct crypto_alg * alg,u32 type,u32 mask)396 static int crypto_nivaead_default(struct crypto_alg *alg, u32 type, u32 mask)
397 {
398 struct rtattr *tb[3];
399 struct {
400 struct rtattr attr;
401 struct crypto_attr_type data;
402 } ptype;
403 struct {
404 struct rtattr attr;
405 struct crypto_attr_alg data;
406 } palg;
407 struct crypto_template *tmpl;
408 struct crypto_instance *inst;
409 struct crypto_alg *larval;
410 const char *geniv;
411 int err;
412
413 larval = crypto_larval_lookup(alg->cra_driver_name,
414 CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV,
415 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
416 err = PTR_ERR(larval);
417 if (IS_ERR(larval))
418 goto out;
419
420 err = -EAGAIN;
421 if (!crypto_is_larval(larval))
422 goto drop_larval;
423
424 ptype.attr.rta_len = sizeof(ptype);
425 ptype.attr.rta_type = CRYPTOA_TYPE;
426 ptype.data.type = type | CRYPTO_ALG_GENIV;
427 /* GENIV tells the template that we're making a default geniv. */
428 ptype.data.mask = mask | CRYPTO_ALG_GENIV;
429 tb[0] = &ptype.attr;
430
431 palg.attr.rta_len = sizeof(palg);
432 palg.attr.rta_type = CRYPTOA_ALG;
433 /* Must use the exact name to locate ourselves. */
434 memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
435 tb[1] = &palg.attr;
436
437 tb[2] = NULL;
438
439 geniv = alg->cra_aead.geniv;
440
441 tmpl = crypto_lookup_template(geniv);
442 err = -ENOENT;
443 if (!tmpl)
444 goto kill_larval;
445
446 inst = tmpl->alloc(tb);
447 err = PTR_ERR(inst);
448 if (IS_ERR(inst))
449 goto put_tmpl;
450
451 if ((err = crypto_register_instance(tmpl, inst))) {
452 tmpl->free(inst);
453 goto put_tmpl;
454 }
455
456 /* Redo the lookup to use the instance we just registered. */
457 err = -EAGAIN;
458
459 put_tmpl:
460 crypto_tmpl_put(tmpl);
461 kill_larval:
462 crypto_larval_kill(larval);
463 drop_larval:
464 crypto_mod_put(larval);
465 out:
466 crypto_mod_put(alg);
467 return err;
468 }
469
crypto_lookup_aead(const char * name,u32 type,u32 mask)470 struct crypto_alg *crypto_lookup_aead(const char *name, u32 type, u32 mask)
471 {
472 struct crypto_alg *alg;
473
474 alg = crypto_alg_mod_lookup(name, type, mask);
475 if (IS_ERR(alg))
476 return alg;
477
478 if (alg->cra_type == &crypto_aead_type)
479 return alg;
480
481 if (!alg->cra_aead.ivsize)
482 return alg;
483
484 crypto_mod_put(alg);
485 alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
486 mask & ~CRYPTO_ALG_TESTED);
487 if (IS_ERR(alg))
488 return alg;
489
490 if (alg->cra_type == &crypto_aead_type) {
491 if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
492 crypto_mod_put(alg);
493 alg = ERR_PTR(-ENOENT);
494 }
495 return alg;
496 }
497
498 BUG_ON(!alg->cra_aead.ivsize);
499
500 return ERR_PTR(crypto_nivaead_default(alg, type, mask));
501 }
502 EXPORT_SYMBOL_GPL(crypto_lookup_aead);
503
crypto_grab_aead(struct crypto_aead_spawn * spawn,const char * name,u32 type,u32 mask)504 int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
505 u32 type, u32 mask)
506 {
507 struct crypto_alg *alg;
508 int err;
509
510 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
511 type |= CRYPTO_ALG_TYPE_AEAD;
512 mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
513 mask |= CRYPTO_ALG_TYPE_MASK;
514
515 alg = crypto_lookup_aead(name, type, mask);
516 if (IS_ERR(alg))
517 return PTR_ERR(alg);
518
519 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
520 crypto_mod_put(alg);
521 return err;
522 }
523 EXPORT_SYMBOL_GPL(crypto_grab_aead);
524
crypto_alloc_aead(const char * alg_name,u32 type,u32 mask)525 struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
526 {
527 struct crypto_tfm *tfm;
528 int err;
529
530 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
531 type |= CRYPTO_ALG_TYPE_AEAD;
532 mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
533 mask |= CRYPTO_ALG_TYPE_MASK;
534
535 for (;;) {
536 struct crypto_alg *alg;
537
538 alg = crypto_lookup_aead(alg_name, type, mask);
539 if (IS_ERR(alg)) {
540 err = PTR_ERR(alg);
541 goto err;
542 }
543
544 tfm = __crypto_alloc_tfm(alg, type, mask);
545 if (!IS_ERR(tfm))
546 return __crypto_aead_cast(tfm);
547
548 crypto_mod_put(alg);
549 err = PTR_ERR(tfm);
550
551 err:
552 if (err != -EAGAIN)
553 break;
554 if (signal_pending(current)) {
555 err = -EINTR;
556 break;
557 }
558 }
559
560 return ERR_PTR(err);
561 }
562 EXPORT_SYMBOL_GPL(crypto_alloc_aead);
563
564 MODULE_LICENSE("GPL");
565 MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
566