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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
29static 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
51static 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
62int 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}
80EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
81
82static unsigned int crypto_aead_ctxsize(struct crypto_alg *alg, u32 type,
83 u32 mask)
84{
85 return alg->cra_ctxsize;
86}
87
88static int no_givcrypt(struct aead_givcrypt_request *req)
89{
90 return -ENOSYS;
91}
92
93static 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
115static 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 snprintf(raead.type, CRYPTO_MAX_ALG_NAME, "%s", "aead");
121 snprintf(raead.geniv, CRYPTO_MAX_ALG_NAME, "%s",
122 aead->geniv ?: "<built-in>");
123
124 raead.blocksize = alg->cra_blocksize;
125 raead.maxauthsize = aead->maxauthsize;
126 raead.ivsize = aead->ivsize;
127
128 if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD,
129 sizeof(struct crypto_report_aead), &raead))
130 goto nla_put_failure;
131 return 0;
132
133nla_put_failure:
134 return -EMSGSIZE;
135}
136#else
137static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
138{
139 return -ENOSYS;
140}
141#endif
142
143static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
144 __attribute__ ((unused));
145static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
146{
147 struct aead_alg *aead = &alg->cra_aead;
148
149 seq_printf(m, "type : aead\n");
150 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
151 "yes" : "no");
152 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
153 seq_printf(m, "ivsize : %u\n", aead->ivsize);
154 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
155 seq_printf(m, "geniv : %s\n", aead->geniv ?: "<built-in>");
156}
157
158const struct crypto_type crypto_aead_type = {
159 .ctxsize = crypto_aead_ctxsize,
160 .init = crypto_init_aead_ops,
161#ifdef CONFIG_PROC_FS
162 .show = crypto_aead_show,
163#endif
164 .report = crypto_aead_report,
165};
166EXPORT_SYMBOL_GPL(crypto_aead_type);
167
168static int aead_null_givencrypt(struct aead_givcrypt_request *req)
169{
170 return crypto_aead_encrypt(&req->areq);
171}
172
173static int aead_null_givdecrypt(struct aead_givcrypt_request *req)
174{
175 return crypto_aead_decrypt(&req->areq);
176}
177
178static int crypto_init_nivaead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
179{
180 struct aead_alg *alg = &tfm->__crt_alg->cra_aead;
181 struct aead_tfm *crt = &tfm->crt_aead;
182
183 if (max(alg->maxauthsize, alg->ivsize) > PAGE_SIZE / 8)
184 return -EINVAL;
185
186 crt->setkey = setkey;
187 crt->encrypt = alg->encrypt;
188 crt->decrypt = alg->decrypt;
189 if (!alg->ivsize) {
190 crt->givencrypt = aead_null_givencrypt;
191 crt->givdecrypt = aead_null_givdecrypt;
192 }
193 crt->base = __crypto_aead_cast(tfm);
194 crt->ivsize = alg->ivsize;
195 crt->authsize = alg->maxauthsize;
196
197 return 0;
198}
199
200#ifdef CONFIG_NET
201static int crypto_nivaead_report(struct sk_buff *skb, struct crypto_alg *alg)
202{
203 struct crypto_report_aead raead;
204 struct aead_alg *aead = &alg->cra_aead;
205
206 snprintf(raead.type, CRYPTO_MAX_ALG_NAME, "%s", "nivaead");
207 snprintf(raead.geniv, CRYPTO_MAX_ALG_NAME, "%s", aead->geniv);
208
209 raead.blocksize = alg->cra_blocksize;
210 raead.maxauthsize = aead->maxauthsize;
211 raead.ivsize = aead->ivsize;
212
213 if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD,
214 sizeof(struct crypto_report_aead), &raead))
215 goto nla_put_failure;
216 return 0;
217
218nla_put_failure:
219 return -EMSGSIZE;
220}
221#else
222static int crypto_nivaead_report(struct sk_buff *skb, struct crypto_alg *alg)
223{
224 return -ENOSYS;
225}
226#endif
227
228
229static void crypto_nivaead_show(struct seq_file *m, struct crypto_alg *alg)
230 __attribute__ ((unused));
231static void crypto_nivaead_show(struct seq_file *m, struct crypto_alg *alg)
232{
233 struct aead_alg *aead = &alg->cra_aead;
234
235 seq_printf(m, "type : nivaead\n");
236 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
237 "yes" : "no");
238 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
239 seq_printf(m, "ivsize : %u\n", aead->ivsize);
240 seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize);
241 seq_printf(m, "geniv : %s\n", aead->geniv);
242}
243
244const struct crypto_type crypto_nivaead_type = {
245 .ctxsize = crypto_aead_ctxsize,
246 .init = crypto_init_nivaead_ops,
247#ifdef CONFIG_PROC_FS
248 .show = crypto_nivaead_show,
249#endif
250 .report = crypto_nivaead_report,
251};
252EXPORT_SYMBOL_GPL(crypto_nivaead_type);
253
254static int crypto_grab_nivaead(struct crypto_aead_spawn *spawn,
255 const char *name, u32 type, u32 mask)
256{
257 struct crypto_alg *alg;
258 int err;
259
260 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
261 type |= CRYPTO_ALG_TYPE_AEAD;
262 mask |= CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV;
263
264 alg = crypto_alg_mod_lookup(name, type, mask);
265 if (IS_ERR(alg))
266 return PTR_ERR(alg);
267
268 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
269 crypto_mod_put(alg);
270 return err;
271}
272
273struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
274 struct rtattr **tb, u32 type,
275 u32 mask)
276{
277 const char *name;
278 struct crypto_aead_spawn *spawn;
279 struct crypto_attr_type *algt;
280 struct crypto_instance *inst;
281 struct crypto_alg *alg;
282 int err;
283
284 algt = crypto_get_attr_type(tb);
285 err = PTR_ERR(algt);
286 if (IS_ERR(algt))
287 return ERR_PTR(err);
288
289 if ((algt->type ^ (CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV)) &
290 algt->mask)
291 return ERR_PTR(-EINVAL);
292
293 name = crypto_attr_alg_name(tb[1]);
294 err = PTR_ERR(name);
295 if (IS_ERR(name))
296 return ERR_PTR(err);
297
298 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
299 if (!inst)
300 return ERR_PTR(-ENOMEM);
301
302 spawn = crypto_instance_ctx(inst);
303
304 /* Ignore async algorithms if necessary. */
305 mask |= crypto_requires_sync(algt->type, algt->mask);
306
307 crypto_set_aead_spawn(spawn, inst);
308 err = crypto_grab_nivaead(spawn, name, type, mask);
309 if (err)
310 goto err_free_inst;
311
312 alg = crypto_aead_spawn_alg(spawn);
313
314 err = -EINVAL;
315 if (!alg->cra_aead.ivsize)
316 goto err_drop_alg;
317
318 /*
319 * This is only true if we're constructing an algorithm with its
320 * default IV generator. For the default generator we elide the
321 * template name and double-check the IV generator.
322 */
323 if (algt->mask & CRYPTO_ALG_GENIV) {
324 if (strcmp(tmpl->name, alg->cra_aead.geniv))
325 goto err_drop_alg;
326
327 memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
328 memcpy(inst->alg.cra_driver_name, alg->cra_driver_name,
329 CRYPTO_MAX_ALG_NAME);
330 } else {
331 err = -ENAMETOOLONG;
332 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
333 "%s(%s)", tmpl->name, alg->cra_name) >=
334 CRYPTO_MAX_ALG_NAME)
335 goto err_drop_alg;
336 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
337 "%s(%s)", tmpl->name, alg->cra_driver_name) >=
338 CRYPTO_MAX_ALG_NAME)
339 goto err_drop_alg;
340 }
341
342 inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV;
343 inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
344 inst->alg.cra_priority = alg->cra_priority;
345 inst->alg.cra_blocksize = alg->cra_blocksize;
346 inst->alg.cra_alignmask = alg->cra_alignmask;
347 inst->alg.cra_type = &crypto_aead_type;
348
349 inst->alg.cra_aead.ivsize = alg->cra_aead.ivsize;
350 inst->alg.cra_aead.maxauthsize = alg->cra_aead.maxauthsize;
351 inst->alg.cra_aead.geniv = alg->cra_aead.geniv;
352
353 inst->alg.cra_aead.setkey = alg->cra_aead.setkey;
354 inst->alg.cra_aead.setauthsize = alg->cra_aead.setauthsize;
355 inst->alg.cra_aead.encrypt = alg->cra_aead.encrypt;
356 inst->alg.cra_aead.decrypt = alg->cra_aead.decrypt;
357
358out:
359 return inst;
360
361err_drop_alg:
362 crypto_drop_aead(spawn);
363err_free_inst:
364 kfree(inst);
365 inst = ERR_PTR(err);
366 goto out;
367}
368EXPORT_SYMBOL_GPL(aead_geniv_alloc);
369
370void aead_geniv_free(struct crypto_instance *inst)
371{
372 crypto_drop_aead(crypto_instance_ctx(inst));
373 kfree(inst);
374}
375EXPORT_SYMBOL_GPL(aead_geniv_free);
376
377int aead_geniv_init(struct crypto_tfm *tfm)
378{
379 struct crypto_instance *inst = (void *)tfm->__crt_alg;
380 struct crypto_aead *aead;
381
382 aead = crypto_spawn_aead(crypto_instance_ctx(inst));
383 if (IS_ERR(aead))
384 return PTR_ERR(aead);
385
386 tfm->crt_aead.base = aead;
387 tfm->crt_aead.reqsize += crypto_aead_reqsize(aead);
388
389 return 0;
390}
391EXPORT_SYMBOL_GPL(aead_geniv_init);
392
393void aead_geniv_exit(struct crypto_tfm *tfm)
394{
395 crypto_free_aead(tfm->crt_aead.base);
396}
397EXPORT_SYMBOL_GPL(aead_geniv_exit);
398
399static int crypto_nivaead_default(struct crypto_alg *alg, u32 type, u32 mask)
400{
401 struct rtattr *tb[3];
402 struct {
403 struct rtattr attr;
404 struct crypto_attr_type data;
405 } ptype;
406 struct {
407 struct rtattr attr;
408 struct crypto_attr_alg data;
409 } palg;
410 struct crypto_template *tmpl;
411 struct crypto_instance *inst;
412 struct crypto_alg *larval;
413 const char *geniv;
414 int err;
415
416 larval = crypto_larval_lookup(alg->cra_driver_name,
417 CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV,
418 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
419 err = PTR_ERR(larval);
420 if (IS_ERR(larval))
421 goto out;
422
423 err = -EAGAIN;
424 if (!crypto_is_larval(larval))
425 goto drop_larval;
426
427 ptype.attr.rta_len = sizeof(ptype);
428 ptype.attr.rta_type = CRYPTOA_TYPE;
429 ptype.data.type = type | CRYPTO_ALG_GENIV;
430 /* GENIV tells the template that we're making a default geniv. */
431 ptype.data.mask = mask | CRYPTO_ALG_GENIV;
432 tb[0] = &ptype.attr;
433
434 palg.attr.rta_len = sizeof(palg);
435 palg.attr.rta_type = CRYPTOA_ALG;
436 /* Must use the exact name to locate ourselves. */
437 memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
438 tb[1] = &palg.attr;
439
440 tb[2] = NULL;
441
442 geniv = alg->cra_aead.geniv;
443
444 tmpl = crypto_lookup_template(geniv);
445 err = -ENOENT;
446 if (!tmpl)
447 goto kill_larval;
448
449 inst = tmpl->alloc(tb);
450 err = PTR_ERR(inst);
451 if (IS_ERR(inst))
452 goto put_tmpl;
453
454 if ((err = crypto_register_instance(tmpl, inst))) {
455 tmpl->free(inst);
456 goto put_tmpl;
457 }
458
459 /* Redo the lookup to use the instance we just registered. */
460 err = -EAGAIN;
461
462put_tmpl:
463 crypto_tmpl_put(tmpl);
464kill_larval:
465 crypto_larval_kill(larval);
466drop_larval:
467 crypto_mod_put(larval);
468out:
469 crypto_mod_put(alg);
470 return err;
471}
472
473struct crypto_alg *crypto_lookup_aead(const char *name, u32 type, u32 mask)
474{
475 struct crypto_alg *alg;
476
477 alg = crypto_alg_mod_lookup(name, type, mask);
478 if (IS_ERR(alg))
479 return alg;
480
481 if (alg->cra_type == &crypto_aead_type)
482 return alg;
483
484 if (!alg->cra_aead.ivsize)
485 return alg;
486
487 crypto_mod_put(alg);
488 alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
489 mask & ~CRYPTO_ALG_TESTED);
490 if (IS_ERR(alg))
491 return alg;
492
493 if (alg->cra_type == &crypto_aead_type) {
494 if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
495 crypto_mod_put(alg);
496 alg = ERR_PTR(-ENOENT);
497 }
498 return alg;
499 }
500
501 BUG_ON(!alg->cra_aead.ivsize);
502
503 return ERR_PTR(crypto_nivaead_default(alg, type, mask));
504}
505EXPORT_SYMBOL_GPL(crypto_lookup_aead);
506
507int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
508 u32 type, u32 mask)
509{
510 struct crypto_alg *alg;
511 int err;
512
513 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
514 type |= CRYPTO_ALG_TYPE_AEAD;
515 mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
516 mask |= CRYPTO_ALG_TYPE_MASK;
517
518 alg = crypto_lookup_aead(name, type, mask);
519 if (IS_ERR(alg))
520 return PTR_ERR(alg);
521
522 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
523 crypto_mod_put(alg);
524 return err;
525}
526EXPORT_SYMBOL_GPL(crypto_grab_aead);
527
528struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
529{
530 struct crypto_tfm *tfm;
531 int err;
532
533 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
534 type |= CRYPTO_ALG_TYPE_AEAD;
535 mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
536 mask |= CRYPTO_ALG_TYPE_MASK;
537
538 for (;;) {
539 struct crypto_alg *alg;
540
541 alg = crypto_lookup_aead(alg_name, type, mask);
542 if (IS_ERR(alg)) {
543 err = PTR_ERR(alg);
544 goto err;
545 }
546
547 tfm = __crypto_alloc_tfm(alg, type, mask);
548 if (!IS_ERR(tfm))
549 return __crypto_aead_cast(tfm);
550
551 crypto_mod_put(alg);
552 err = PTR_ERR(tfm);
553
554err:
555 if (err != -EAGAIN)
556 break;
557 if (signal_pending(current)) {
558 err = -EINTR;
559 break;
560 }
561 }
562
563 return ERR_PTR(err);
564}
565EXPORT_SYMBOL_GPL(crypto_alloc_aead);
566
567MODULE_LICENSE("GPL");
568MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");