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16#include <crypto/internal/skcipher.h>
17#include <linux/cpumask.h>
18#include <linux/err.h>
19#include <linux/init.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/rtnetlink.h>
23#include <linux/sched.h>
24#include <linux/slab.h>
25#include <linux/seq_file.h>
26
27#include <crypto/scatterwalk.h>
28
29#include "internal.h"
30
31static const char *skcipher_default_geniv __read_mostly;
32
33struct ablkcipher_buffer {
34 struct list_head entry;
35 struct scatter_walk dst;
36 unsigned int len;
37 void *data;
38};
39
40enum {
41 ABLKCIPHER_WALK_SLOW = 1 << 0,
42};
43
44static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
45{
46 scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
47}
48
49void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
50{
51 struct ablkcipher_buffer *p, *tmp;
52
53 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
54 ablkcipher_buffer_write(p);
55 list_del(&p->entry);
56 kfree(p);
57 }
58}
59EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);
60
61static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
62 struct ablkcipher_buffer *p)
63{
64 p->dst = walk->out;
65 list_add_tail(&p->entry, &walk->buffers);
66}
67
68
69
70
71static inline u8 *ablkcipher_get_spot(u8 *start, unsigned int len)
72{
73 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
74 return max(start, end_page);
75}
76
77static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
78 unsigned int bsize)
79{
80 unsigned int n = bsize;
81
82 for (;;) {
83 unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
84
85 if (len_this_page > n)
86 len_this_page = n;
87 scatterwalk_advance(&walk->out, n);
88 if (n == len_this_page)
89 break;
90 n -= len_this_page;
91 scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg));
92 }
93
94 return bsize;
95}
96
97static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
98 unsigned int n)
99{
100 scatterwalk_advance(&walk->in, n);
101 scatterwalk_advance(&walk->out, n);
102
103 return n;
104}
105
106static int ablkcipher_walk_next(struct ablkcipher_request *req,
107 struct ablkcipher_walk *walk);
108
109int ablkcipher_walk_done(struct ablkcipher_request *req,
110 struct ablkcipher_walk *walk, int err)
111{
112 struct crypto_tfm *tfm = req->base.tfm;
113 unsigned int nbytes = 0;
114
115 if (likely(err >= 0)) {
116 unsigned int n = walk->nbytes - err;
117
118 if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
119 n = ablkcipher_done_fast(walk, n);
120 else if (WARN_ON(err)) {
121 err = -EINVAL;
122 goto err;
123 } else
124 n = ablkcipher_done_slow(walk, n);
125
126 nbytes = walk->total - n;
127 err = 0;
128 }
129
130 scatterwalk_done(&walk->in, 0, nbytes);
131 scatterwalk_done(&walk->out, 1, nbytes);
132
133err:
134 walk->total = nbytes;
135 walk->nbytes = nbytes;
136
137 if (nbytes) {
138 crypto_yield(req->base.flags);
139 return ablkcipher_walk_next(req, walk);
140 }
141
142 if (walk->iv != req->info)
143 memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
144 if (walk->iv_buffer)
145 kfree(walk->iv_buffer);
146
147 return err;
148}
149EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
150
151static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
152 struct ablkcipher_walk *walk,
153 unsigned int bsize,
154 unsigned int alignmask,
155 void **src_p, void **dst_p)
156{
157 unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
158 struct ablkcipher_buffer *p;
159 void *src, *dst, *base;
160 unsigned int n;
161
162 n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
163 n += (aligned_bsize * 3 - (alignmask + 1) +
164 (alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
165
166 p = kmalloc(n, GFP_ATOMIC);
167 if (!p)
168 return ablkcipher_walk_done(req, walk, -ENOMEM);
169
170 base = p + 1;
171
172 dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
173 src = dst = ablkcipher_get_spot(dst, bsize);
174
175 p->len = bsize;
176 p->data = dst;
177
178 scatterwalk_copychunks(src, &walk->in, bsize, 0);
179
180 ablkcipher_queue_write(walk, p);
181
182 walk->nbytes = bsize;
183 walk->flags |= ABLKCIPHER_WALK_SLOW;
184
185 *src_p = src;
186 *dst_p = dst;
187
188 return 0;
189}
190
191static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
192 struct crypto_tfm *tfm,
193 unsigned int alignmask)
194{
195 unsigned bs = walk->blocksize;
196 unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
197 unsigned aligned_bs = ALIGN(bs, alignmask + 1);
198 unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
199 (alignmask + 1);
200 u8 *iv;
201
202 size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
203 walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
204 if (!walk->iv_buffer)
205 return -ENOMEM;
206
207 iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
208 iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
209 iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
210 iv = ablkcipher_get_spot(iv, ivsize);
211
212 walk->iv = memcpy(iv, walk->iv, ivsize);
213 return 0;
214}
215
216static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
217 struct ablkcipher_walk *walk)
218{
219 walk->src.page = scatterwalk_page(&walk->in);
220 walk->src.offset = offset_in_page(walk->in.offset);
221 walk->dst.page = scatterwalk_page(&walk->out);
222 walk->dst.offset = offset_in_page(walk->out.offset);
223
224 return 0;
225}
226
227static int ablkcipher_walk_next(struct ablkcipher_request *req,
228 struct ablkcipher_walk *walk)
229{
230 struct crypto_tfm *tfm = req->base.tfm;
231 unsigned int alignmask, bsize, n;
232 void *src, *dst;
233 int err;
234
235 alignmask = crypto_tfm_alg_alignmask(tfm);
236 n = walk->total;
237 if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
238 req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
239 return ablkcipher_walk_done(req, walk, -EINVAL);
240 }
241
242 walk->flags &= ~ABLKCIPHER_WALK_SLOW;
243 src = dst = NULL;
244
245 bsize = min(walk->blocksize, n);
246 n = scatterwalk_clamp(&walk->in, n);
247 n = scatterwalk_clamp(&walk->out, n);
248
249 if (n < bsize ||
250 !scatterwalk_aligned(&walk->in, alignmask) ||
251 !scatterwalk_aligned(&walk->out, alignmask)) {
252 err = ablkcipher_next_slow(req, walk, bsize, alignmask,
253 &src, &dst);
254 goto set_phys_lowmem;
255 }
256
257 walk->nbytes = n;
258
259 return ablkcipher_next_fast(req, walk);
260
261set_phys_lowmem:
262 if (err >= 0) {
263 walk->src.page = virt_to_page(src);
264 walk->dst.page = virt_to_page(dst);
265 walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
266 walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
267 }
268
269 return err;
270}
271
272static int ablkcipher_walk_first(struct ablkcipher_request *req,
273 struct ablkcipher_walk *walk)
274{
275 struct crypto_tfm *tfm = req->base.tfm;
276 unsigned int alignmask;
277
278 alignmask = crypto_tfm_alg_alignmask(tfm);
279 if (WARN_ON_ONCE(in_irq()))
280 return -EDEADLK;
281
282 walk->nbytes = walk->total;
283 if (unlikely(!walk->total))
284 return 0;
285
286 walk->iv_buffer = NULL;
287 walk->iv = req->info;
288 if (unlikely(((unsigned long)walk->iv & alignmask))) {
289 int err = ablkcipher_copy_iv(walk, tfm, alignmask);
290 if (err)
291 return err;
292 }
293
294 scatterwalk_start(&walk->in, walk->in.sg);
295 scatterwalk_start(&walk->out, walk->out.sg);
296
297 return ablkcipher_walk_next(req, walk);
298}
299
300int ablkcipher_walk_phys(struct ablkcipher_request *req,
301 struct ablkcipher_walk *walk)
302{
303 walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
304 return ablkcipher_walk_first(req, walk);
305}
306EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
307
308static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
309 unsigned int keylen)
310{
311 struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
312 unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
313 int ret;
314 u8 *buffer, *alignbuffer;
315 unsigned long absize;
316
317 absize = keylen + alignmask;
318 buffer = kmalloc(absize, GFP_ATOMIC);
319 if (!buffer)
320 return -ENOMEM;
321
322 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
323 memcpy(alignbuffer, key, keylen);
324 ret = cipher->setkey(tfm, alignbuffer, keylen);
325 memset(alignbuffer, 0, keylen);
326 kfree(buffer);
327 return ret;
328}
329
330static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
331 unsigned int keylen)
332{
333 struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
334 unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
335
336 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
337 crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
338 return -EINVAL;
339 }
340
341 if ((unsigned long)key & alignmask)
342 return setkey_unaligned(tfm, key, keylen);
343
344 return cipher->setkey(tfm, key, keylen);
345}
346
347static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
348 u32 mask)
349{
350 return alg->cra_ctxsize;
351}
352
353int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
354{
355 return crypto_ablkcipher_encrypt(&req->creq);
356}
357
358int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
359{
360 return crypto_ablkcipher_decrypt(&req->creq);
361}
362
363static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
364 u32 mask)
365{
366 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
367 struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
368
369 if (alg->ivsize > PAGE_SIZE / 8)
370 return -EINVAL;
371
372 crt->setkey = setkey;
373 crt->encrypt = alg->encrypt;
374 crt->decrypt = alg->decrypt;
375 if (!alg->ivsize) {
376 crt->givencrypt = skcipher_null_givencrypt;
377 crt->givdecrypt = skcipher_null_givdecrypt;
378 }
379 crt->base = __crypto_ablkcipher_cast(tfm);
380 crt->ivsize = alg->ivsize;
381
382 return 0;
383}
384
385static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
386 __attribute__ ((unused));
387static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
388{
389 struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
390
391 seq_printf(m, "type : ablkcipher\n");
392 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
393 "yes" : "no");
394 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
395 seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
396 seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
397 seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
398 seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
399}
400
401const struct crypto_type crypto_ablkcipher_type = {
402 .ctxsize = crypto_ablkcipher_ctxsize,
403 .init = crypto_init_ablkcipher_ops,
404#ifdef CONFIG_PROC_FS
405 .show = crypto_ablkcipher_show,
406#endif
407};
408EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
409
410static int no_givdecrypt(struct skcipher_givcrypt_request *req)
411{
412 return -ENOSYS;
413}
414
415static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
416 u32 mask)
417{
418 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
419 struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
420
421 if (alg->ivsize > PAGE_SIZE / 8)
422 return -EINVAL;
423
424 crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
425 alg->setkey : setkey;
426 crt->encrypt = alg->encrypt;
427 crt->decrypt = alg->decrypt;
428 crt->givencrypt = alg->givencrypt;
429 crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
430 crt->base = __crypto_ablkcipher_cast(tfm);
431 crt->ivsize = alg->ivsize;
432
433 return 0;
434}
435
436static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
437 __attribute__ ((unused));
438static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
439{
440 struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
441
442 seq_printf(m, "type : givcipher\n");
443 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
444 "yes" : "no");
445 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
446 seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
447 seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
448 seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
449 seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
450}
451
452const struct crypto_type crypto_givcipher_type = {
453 .ctxsize = crypto_ablkcipher_ctxsize,
454 .init = crypto_init_givcipher_ops,
455#ifdef CONFIG_PROC_FS
456 .show = crypto_givcipher_show,
457#endif
458};
459EXPORT_SYMBOL_GPL(crypto_givcipher_type);
460
461const char *crypto_default_geniv(const struct crypto_alg *alg)
462{
463 if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
464 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
465 alg->cra_ablkcipher.ivsize) !=
466 alg->cra_blocksize)
467 return "chainiv";
468
469 return alg->cra_flags & CRYPTO_ALG_ASYNC ?
470 "eseqiv" : skcipher_default_geniv;
471}
472
473static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
474{
475 struct rtattr *tb[3];
476 struct {
477 struct rtattr attr;
478 struct crypto_attr_type data;
479 } ptype;
480 struct {
481 struct rtattr attr;
482 struct crypto_attr_alg data;
483 } palg;
484 struct crypto_template *tmpl;
485 struct crypto_instance *inst;
486 struct crypto_alg *larval;
487 const char *geniv;
488 int err;
489
490 larval = crypto_larval_lookup(alg->cra_driver_name,
491 (type & ~CRYPTO_ALG_TYPE_MASK) |
492 CRYPTO_ALG_TYPE_GIVCIPHER,
493 mask | CRYPTO_ALG_TYPE_MASK);
494 err = PTR_ERR(larval);
495 if (IS_ERR(larval))
496 goto out;
497
498 err = -EAGAIN;
499 if (!crypto_is_larval(larval))
500 goto drop_larval;
501
502 ptype.attr.rta_len = sizeof(ptype);
503 ptype.attr.rta_type = CRYPTOA_TYPE;
504 ptype.data.type = type | CRYPTO_ALG_GENIV;
505
506 ptype.data.mask = mask | CRYPTO_ALG_GENIV;
507 tb[0] = &ptype.attr;
508
509 palg.attr.rta_len = sizeof(palg);
510 palg.attr.rta_type = CRYPTOA_ALG;
511
512 memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
513 tb[1] = &palg.attr;
514
515 tb[2] = NULL;
516
517 if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
518 CRYPTO_ALG_TYPE_BLKCIPHER)
519 geniv = alg->cra_blkcipher.geniv;
520 else
521 geniv = alg->cra_ablkcipher.geniv;
522
523 if (!geniv)
524 geniv = crypto_default_geniv(alg);
525
526 tmpl = crypto_lookup_template(geniv);
527 err = -ENOENT;
528 if (!tmpl)
529 goto kill_larval;
530
531 inst = tmpl->alloc(tb);
532 err = PTR_ERR(inst);
533 if (IS_ERR(inst))
534 goto put_tmpl;
535
536 if ((err = crypto_register_instance(tmpl, inst))) {
537 tmpl->free(inst);
538 goto put_tmpl;
539 }
540
541
542 err = -EAGAIN;
543
544put_tmpl:
545 crypto_tmpl_put(tmpl);
546kill_larval:
547 crypto_larval_kill(larval);
548drop_larval:
549 crypto_mod_put(larval);
550out:
551 crypto_mod_put(alg);
552 return err;
553}
554
555static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
556 u32 mask)
557{
558 struct crypto_alg *alg;
559
560 alg = crypto_alg_mod_lookup(name, type, mask);
561 if (IS_ERR(alg))
562 return alg;
563
564 if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
565 CRYPTO_ALG_TYPE_GIVCIPHER)
566 return alg;
567
568 if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
569 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
570 alg->cra_ablkcipher.ivsize))
571 return alg;
572
573 crypto_mod_put(alg);
574 alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
575 mask & ~CRYPTO_ALG_TESTED);
576 if (IS_ERR(alg))
577 return alg;
578
579 if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
580 CRYPTO_ALG_TYPE_GIVCIPHER) {
581 if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
582 crypto_mod_put(alg);
583 alg = ERR_PTR(-ENOENT);
584 }
585 return alg;
586 }
587
588 BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
589 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
590 alg->cra_ablkcipher.ivsize));
591
592 return ERR_PTR(crypto_givcipher_default(alg, type, mask));
593}
594
595int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
596 u32 type, u32 mask)
597{
598 struct crypto_alg *alg;
599 int err;
600
601 type = crypto_skcipher_type(type);
602 mask = crypto_skcipher_mask(mask);
603
604 alg = crypto_lookup_skcipher(name, type, mask);
605 if (IS_ERR(alg))
606 return PTR_ERR(alg);
607
608 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
609 crypto_mod_put(alg);
610 return err;
611}
612EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
613
614struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
615 u32 type, u32 mask)
616{
617 struct crypto_tfm *tfm;
618 int err;
619
620 type = crypto_skcipher_type(type);
621 mask = crypto_skcipher_mask(mask);
622
623 for (;;) {
624 struct crypto_alg *alg;
625
626 alg = crypto_lookup_skcipher(alg_name, type, mask);
627 if (IS_ERR(alg)) {
628 err = PTR_ERR(alg);
629 goto err;
630 }
631
632 tfm = __crypto_alloc_tfm(alg, type, mask);
633 if (!IS_ERR(tfm))
634 return __crypto_ablkcipher_cast(tfm);
635
636 crypto_mod_put(alg);
637 err = PTR_ERR(tfm);
638
639err:
640 if (err != -EAGAIN)
641 break;
642 if (signal_pending(current)) {
643 err = -EINTR;
644 break;
645 }
646 }
647
648 return ERR_PTR(err);
649}
650EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);
651
652static int __init skcipher_module_init(void)
653{
654 skcipher_default_geniv = num_possible_cpus() > 1 ?
655 "eseqiv" : "chainiv";
656 return 0;
657}
658
659static void skcipher_module_exit(void)
660{
661}
662
663module_init(skcipher_module_init);
664module_exit(skcipher_module_exit);
665
