gpu: nvgpu: post events on all channels of TSG.
[linux-3.10.git] / crypto / blkcipher.c
1 /*
2  * Block chaining cipher operations.
3  * 
4  * Generic encrypt/decrypt wrapper for ciphers, handles operations across
5  * multiple page boundaries by using temporary blocks.  In user context,
6  * the kernel is given a chance to schedule us once per page.
7  *
8  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License as published by the Free
12  * Software Foundation; either version 2 of the License, or (at your option) 
13  * any later version.
14  *
15  */
16
17 #include <crypto/internal/skcipher.h>
18 #include <crypto/scatterwalk.h>
19 #include <linux/errno.h>
20 #include <linux/hardirq.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/scatterlist.h>
24 #include <linux/seq_file.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include <linux/cryptouser.h>
28 #include <net/netlink.h>
29
30 #include "internal.h"
31
32 enum {
33         BLKCIPHER_WALK_PHYS = 1 << 0,
34         BLKCIPHER_WALK_SLOW = 1 << 1,
35         BLKCIPHER_WALK_COPY = 1 << 2,
36         BLKCIPHER_WALK_DIFF = 1 << 3,
37 };
38
39 static int blkcipher_walk_next(struct blkcipher_desc *desc,
40                                struct blkcipher_walk *walk);
41 static int blkcipher_walk_first(struct blkcipher_desc *desc,
42                                 struct blkcipher_walk *walk);
43
44 static inline void blkcipher_map_src(struct blkcipher_walk *walk)
45 {
46         walk->src.virt.addr = scatterwalk_map(&walk->in);
47 }
48
49 static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
50 {
51         walk->dst.virt.addr = scatterwalk_map(&walk->out);
52 }
53
54 static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
55 {
56         scatterwalk_unmap(walk->src.virt.addr);
57 }
58
59 static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
60 {
61         scatterwalk_unmap(walk->dst.virt.addr);
62 }
63
64 /* Get a spot of the specified length that does not straddle a page.
65  * The caller needs to ensure that there is enough space for this operation.
66  */
67 static inline u8 *blkcipher_get_spot(u8 *start, unsigned int len)
68 {
69         u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
70         return max(start, end_page);
71 }
72
73 static inline unsigned int blkcipher_done_slow(struct blkcipher_walk *walk,
74                                                unsigned int bsize)
75 {
76         u8 *addr;
77
78         addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
79         addr = blkcipher_get_spot(addr, bsize);
80         scatterwalk_copychunks(addr, &walk->out, bsize, 1);
81         return bsize;
82 }
83
84 static inline unsigned int blkcipher_done_fast(struct blkcipher_walk *walk,
85                                                unsigned int n)
86 {
87         if (walk->flags & BLKCIPHER_WALK_COPY) {
88                 blkcipher_map_dst(walk);
89                 memcpy(walk->dst.virt.addr, walk->page, n);
90                 blkcipher_unmap_dst(walk);
91         } else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
92                 if (walk->flags & BLKCIPHER_WALK_DIFF)
93                         blkcipher_unmap_dst(walk);
94                 blkcipher_unmap_src(walk);
95         }
96
97         scatterwalk_advance(&walk->in, n);
98         scatterwalk_advance(&walk->out, n);
99
100         return n;
101 }
102
103 int blkcipher_walk_done(struct blkcipher_desc *desc,
104                         struct blkcipher_walk *walk, int err)
105 {
106         unsigned int nbytes = 0;
107
108         if (likely(err >= 0)) {
109                 unsigned int n = walk->nbytes - err;
110
111                 if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW)))
112                         n = blkcipher_done_fast(walk, n);
113                 else if (WARN_ON(err)) {
114                         err = -EINVAL;
115                         goto err;
116                 } else
117                         n = blkcipher_done_slow(walk, n);
118
119                 nbytes = walk->total - n;
120                 err = 0;
121         }
122
123         scatterwalk_done(&walk->in, 0, nbytes);
124         scatterwalk_done(&walk->out, 1, nbytes);
125
126 err:
127         walk->total = nbytes;
128         walk->nbytes = nbytes;
129
130         if (nbytes) {
131                 crypto_yield(desc->flags);
132                 return blkcipher_walk_next(desc, walk);
133         }
134
135         if (walk->iv != desc->info)
136                 memcpy(desc->info, walk->iv, walk->ivsize);
137         if (walk->buffer != walk->page)
138                 kfree(walk->buffer);
139         if (walk->page)
140                 free_page((unsigned long)walk->page);
141
142         return err;
143 }
144 EXPORT_SYMBOL_GPL(blkcipher_walk_done);
145
146 static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
147                                       struct blkcipher_walk *walk,
148                                       unsigned int bsize,
149                                       unsigned int alignmask)
150 {
151         unsigned int n;
152         unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
153
154         if (walk->buffer)
155                 goto ok;
156
157         walk->buffer = walk->page;
158         if (walk->buffer)
159                 goto ok;
160
161         n = aligned_bsize * 3 - (alignmask + 1) +
162             (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
163         walk->buffer = kmalloc(n, GFP_ATOMIC);
164         if (!walk->buffer)
165                 return blkcipher_walk_done(desc, walk, -ENOMEM);
166
167 ok:
168         walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
169                                           alignmask + 1);
170         walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
171         walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr +
172                                                  aligned_bsize, bsize);
173
174         scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
175
176         walk->nbytes = bsize;
177         walk->flags |= BLKCIPHER_WALK_SLOW;
178
179         return 0;
180 }
181
182 static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
183 {
184         u8 *tmp = walk->page;
185
186         blkcipher_map_src(walk);
187         memcpy(tmp, walk->src.virt.addr, walk->nbytes);
188         blkcipher_unmap_src(walk);
189
190         walk->src.virt.addr = tmp;
191         walk->dst.virt.addr = tmp;
192
193         return 0;
194 }
195
196 static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
197                                       struct blkcipher_walk *walk)
198 {
199         unsigned long diff;
200
201         walk->src.phys.page = scatterwalk_page(&walk->in);
202         walk->src.phys.offset = offset_in_page(walk->in.offset);
203         walk->dst.phys.page = scatterwalk_page(&walk->out);
204         walk->dst.phys.offset = offset_in_page(walk->out.offset);
205
206         if (walk->flags & BLKCIPHER_WALK_PHYS)
207                 return 0;
208
209         diff = walk->src.phys.offset - walk->dst.phys.offset;
210         diff |= walk->src.virt.page - walk->dst.virt.page;
211
212         blkcipher_map_src(walk);
213         walk->dst.virt.addr = walk->src.virt.addr;
214
215         if (diff) {
216                 walk->flags |= BLKCIPHER_WALK_DIFF;
217                 blkcipher_map_dst(walk);
218         }
219
220         return 0;
221 }
222
223 static int blkcipher_walk_next(struct blkcipher_desc *desc,
224                                struct blkcipher_walk *walk)
225 {
226         unsigned int bsize;
227         unsigned int n;
228         int err;
229
230         n = walk->total;
231         if (unlikely(n < walk->cipher_blocksize)) {
232                 desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
233                 return blkcipher_walk_done(desc, walk, -EINVAL);
234         }
235
236         walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY |
237                          BLKCIPHER_WALK_DIFF);
238         if (!scatterwalk_aligned(&walk->in, walk->alignmask) ||
239             !scatterwalk_aligned(&walk->out, walk->alignmask)) {
240                 walk->flags |= BLKCIPHER_WALK_COPY;
241                 if (!walk->page) {
242                         walk->page = (void *)__get_free_page(GFP_ATOMIC);
243                         if (!walk->page)
244                                 n = 0;
245                 }
246         }
247
248         bsize = min(walk->walk_blocksize, n);
249         n = scatterwalk_clamp(&walk->in, n);
250         n = scatterwalk_clamp(&walk->out, n);
251
252         if (unlikely(n < bsize)) {
253                 err = blkcipher_next_slow(desc, walk, bsize, walk->alignmask);
254                 goto set_phys_lowmem;
255         }
256
257         walk->nbytes = n;
258         if (walk->flags & BLKCIPHER_WALK_COPY) {
259                 err = blkcipher_next_copy(walk);
260                 goto set_phys_lowmem;
261         }
262
263         return blkcipher_next_fast(desc, walk);
264
265 set_phys_lowmem:
266         if (walk->flags & BLKCIPHER_WALK_PHYS) {
267                 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
268                 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
269                 walk->src.phys.offset &= PAGE_SIZE - 1;
270                 walk->dst.phys.offset &= PAGE_SIZE - 1;
271         }
272         return err;
273 }
274
275 static inline int blkcipher_copy_iv(struct blkcipher_walk *walk)
276 {
277         unsigned bs = walk->walk_blocksize;
278         unsigned aligned_bs = ALIGN(bs, walk->alignmask + 1);
279         unsigned int size = aligned_bs * 2 +
280                             walk->ivsize + max(aligned_bs, walk->ivsize) -
281                             (walk->alignmask + 1);
282         u8 *iv;
283
284         size += walk->alignmask & ~(crypto_tfm_ctx_alignment() - 1);
285         walk->buffer = kmalloc(size, GFP_ATOMIC);
286         if (!walk->buffer)
287                 return -ENOMEM;
288
289         iv = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
290         iv = blkcipher_get_spot(iv, bs) + aligned_bs;
291         iv = blkcipher_get_spot(iv, bs) + aligned_bs;
292         iv = blkcipher_get_spot(iv, walk->ivsize);
293
294         walk->iv = memcpy(iv, walk->iv, walk->ivsize);
295         return 0;
296 }
297
298 int blkcipher_walk_virt(struct blkcipher_desc *desc,
299                         struct blkcipher_walk *walk)
300 {
301         walk->flags &= ~BLKCIPHER_WALK_PHYS;
302         walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
303         walk->cipher_blocksize = walk->walk_blocksize;
304         walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
305         walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
306         return blkcipher_walk_first(desc, walk);
307 }
308 EXPORT_SYMBOL_GPL(blkcipher_walk_virt);
309
310 int blkcipher_walk_phys(struct blkcipher_desc *desc,
311                         struct blkcipher_walk *walk)
312 {
313         walk->flags |= BLKCIPHER_WALK_PHYS;
314         walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
315         walk->cipher_blocksize = walk->walk_blocksize;
316         walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
317         walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
318         return blkcipher_walk_first(desc, walk);
319 }
320 EXPORT_SYMBOL_GPL(blkcipher_walk_phys);
321
322 static int blkcipher_walk_first(struct blkcipher_desc *desc,
323                                 struct blkcipher_walk *walk)
324 {
325         if (WARN_ON_ONCE(in_irq()))
326                 return -EDEADLK;
327
328         walk->nbytes = walk->total;
329         if (unlikely(!walk->total))
330                 return 0;
331
332         walk->buffer = NULL;
333         walk->iv = desc->info;
334         if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
335                 int err = blkcipher_copy_iv(walk);
336                 if (err)
337                         return err;
338         }
339
340         scatterwalk_start(&walk->in, walk->in.sg);
341         scatterwalk_start(&walk->out, walk->out.sg);
342         walk->page = NULL;
343
344         return blkcipher_walk_next(desc, walk);
345 }
346
347 int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
348                               struct blkcipher_walk *walk,
349                               unsigned int blocksize)
350 {
351         walk->flags &= ~BLKCIPHER_WALK_PHYS;
352         walk->walk_blocksize = blocksize;
353         walk->cipher_blocksize = crypto_blkcipher_blocksize(desc->tfm);
354         walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
355         walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
356         return blkcipher_walk_first(desc, walk);
357 }
358 EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block);
359
360 int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc,
361                                    struct blkcipher_walk *walk,
362                                    struct crypto_aead *tfm,
363                                    unsigned int blocksize)
364 {
365         walk->flags &= ~BLKCIPHER_WALK_PHYS;
366         walk->walk_blocksize = blocksize;
367         walk->cipher_blocksize = crypto_aead_blocksize(tfm);
368         walk->ivsize = crypto_aead_ivsize(tfm);
369         walk->alignmask = crypto_aead_alignmask(tfm);
370         return blkcipher_walk_first(desc, walk);
371 }
372 EXPORT_SYMBOL_GPL(blkcipher_aead_walk_virt_block);
373
374 static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
375                             unsigned int keylen)
376 {
377         struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
378         unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
379         int ret;
380         u8 *buffer, *alignbuffer;
381         unsigned long absize;
382
383         absize = keylen + alignmask;
384         buffer = kmalloc(absize, GFP_ATOMIC);
385         if (!buffer)
386                 return -ENOMEM;
387
388         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
389         memcpy(alignbuffer, key, keylen);
390         ret = cipher->setkey(tfm, alignbuffer, keylen);
391         memset(alignbuffer, 0, keylen);
392         kfree(buffer);
393         return ret;
394 }
395
396 static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
397 {
398         struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
399         unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
400
401         if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
402                 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
403                 return -EINVAL;
404         }
405
406         if ((unsigned long)key & alignmask)
407                 return setkey_unaligned(tfm, key, keylen);
408
409         return cipher->setkey(tfm, key, keylen);
410 }
411
412 static int async_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
413                         unsigned int keylen)
414 {
415         return setkey(crypto_ablkcipher_tfm(tfm), key, keylen);
416 }
417
418 static int async_encrypt(struct ablkcipher_request *req)
419 {
420         struct crypto_tfm *tfm = req->base.tfm;
421         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
422         struct blkcipher_desc desc = {
423                 .tfm = __crypto_blkcipher_cast(tfm),
424                 .info = req->info,
425                 .flags = req->base.flags,
426         };
427
428
429         return alg->encrypt(&desc, req->dst, req->src, req->nbytes);
430 }
431
432 static int async_decrypt(struct ablkcipher_request *req)
433 {
434         struct crypto_tfm *tfm = req->base.tfm;
435         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
436         struct blkcipher_desc desc = {
437                 .tfm = __crypto_blkcipher_cast(tfm),
438                 .info = req->info,
439                 .flags = req->base.flags,
440         };
441
442         return alg->decrypt(&desc, req->dst, req->src, req->nbytes);
443 }
444
445 static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type,
446                                              u32 mask)
447 {
448         struct blkcipher_alg *cipher = &alg->cra_blkcipher;
449         unsigned int len = alg->cra_ctxsize;
450
451         if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK &&
452             cipher->ivsize) {
453                 len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
454                 len += cipher->ivsize;
455         }
456
457         return len;
458 }
459
460 static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm)
461 {
462         struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
463         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
464
465         crt->setkey = async_setkey;
466         crt->encrypt = async_encrypt;
467         crt->decrypt = async_decrypt;
468         if (!alg->ivsize) {
469                 crt->givencrypt = skcipher_null_givencrypt;
470                 crt->givdecrypt = skcipher_null_givdecrypt;
471         }
472         crt->base = __crypto_ablkcipher_cast(tfm);
473         crt->ivsize = alg->ivsize;
474
475         return 0;
476 }
477
478 static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm)
479 {
480         struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
481         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
482         unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
483         unsigned long addr;
484
485         crt->setkey = setkey;
486         crt->encrypt = alg->encrypt;
487         crt->decrypt = alg->decrypt;
488
489         addr = (unsigned long)crypto_tfm_ctx(tfm);
490         addr = ALIGN(addr, align);
491         addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
492         crt->iv = (void *)addr;
493
494         return 0;
495 }
496
497 static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
498 {
499         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
500
501         if (alg->ivsize > PAGE_SIZE / 8)
502                 return -EINVAL;
503
504         if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK)
505                 return crypto_init_blkcipher_ops_sync(tfm);
506         else
507                 return crypto_init_blkcipher_ops_async(tfm);
508 }
509
510 #ifdef CONFIG_NET
511 static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
512 {
513         struct crypto_report_blkcipher rblkcipher;
514
515         strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
516         strncpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "<default>",
517                 sizeof(rblkcipher.geniv));
518
519         rblkcipher.blocksize = alg->cra_blocksize;
520         rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
521         rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
522         rblkcipher.ivsize = alg->cra_blkcipher.ivsize;
523
524         if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
525                     sizeof(struct crypto_report_blkcipher), &rblkcipher))
526                 goto nla_put_failure;
527         return 0;
528
529 nla_put_failure:
530         return -EMSGSIZE;
531 }
532 #else
533 static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
534 {
535         return -ENOSYS;
536 }
537 #endif
538
539 static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
540         __attribute__ ((unused));
541 static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
542 {
543         seq_printf(m, "type         : blkcipher\n");
544         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
545         seq_printf(m, "min keysize  : %u\n", alg->cra_blkcipher.min_keysize);
546         seq_printf(m, "max keysize  : %u\n", alg->cra_blkcipher.max_keysize);
547         seq_printf(m, "ivsize       : %u\n", alg->cra_blkcipher.ivsize);
548         seq_printf(m, "geniv        : %s\n", alg->cra_blkcipher.geniv ?:
549                                              "<default>");
550 }
551
552 const struct crypto_type crypto_blkcipher_type = {
553         .ctxsize = crypto_blkcipher_ctxsize,
554         .init = crypto_init_blkcipher_ops,
555 #ifdef CONFIG_PROC_FS
556         .show = crypto_blkcipher_show,
557 #endif
558         .report = crypto_blkcipher_report,
559 };
560 EXPORT_SYMBOL_GPL(crypto_blkcipher_type);
561
562 static int crypto_grab_nivcipher(struct crypto_skcipher_spawn *spawn,
563                                 const char *name, u32 type, u32 mask)
564 {
565         struct crypto_alg *alg;
566         int err;
567
568         type = crypto_skcipher_type(type);
569         mask = crypto_skcipher_mask(mask)| CRYPTO_ALG_GENIV;
570
571         alg = crypto_alg_mod_lookup(name, type, mask);
572         if (IS_ERR(alg))
573                 return PTR_ERR(alg);
574
575         err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
576         crypto_mod_put(alg);
577         return err;
578 }
579
580 struct crypto_instance *skcipher_geniv_alloc(struct crypto_template *tmpl,
581                                              struct rtattr **tb, u32 type,
582                                              u32 mask)
583 {
584         struct {
585                 int (*setkey)(struct crypto_ablkcipher *tfm, const u8 *key,
586                               unsigned int keylen);
587                 int (*encrypt)(struct ablkcipher_request *req);
588                 int (*decrypt)(struct ablkcipher_request *req);
589
590                 unsigned int min_keysize;
591                 unsigned int max_keysize;
592                 unsigned int ivsize;
593
594                 const char *geniv;
595         } balg;
596         const char *name;
597         struct crypto_skcipher_spawn *spawn;
598         struct crypto_attr_type *algt;
599         struct crypto_instance *inst;
600         struct crypto_alg *alg;
601         int err;
602
603         algt = crypto_get_attr_type(tb);
604         if (IS_ERR(algt))
605                 return ERR_CAST(algt);
606
607         if ((algt->type ^ (CRYPTO_ALG_TYPE_GIVCIPHER | CRYPTO_ALG_GENIV)) &
608             algt->mask)
609                 return ERR_PTR(-EINVAL);
610
611         name = crypto_attr_alg_name(tb[1]);
612         if (IS_ERR(name))
613                 return ERR_CAST(name);
614
615         inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
616         if (!inst)
617                 return ERR_PTR(-ENOMEM);
618
619         spawn = crypto_instance_ctx(inst);
620
621         /* Ignore async algorithms if necessary. */
622         mask |= crypto_requires_sync(algt->type, algt->mask);
623
624         crypto_set_skcipher_spawn(spawn, inst);
625         err = crypto_grab_nivcipher(spawn, name, type, mask);
626         if (err)
627                 goto err_free_inst;
628
629         alg = crypto_skcipher_spawn_alg(spawn);
630
631         if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
632             CRYPTO_ALG_TYPE_BLKCIPHER) {
633                 balg.ivsize = alg->cra_blkcipher.ivsize;
634                 balg.min_keysize = alg->cra_blkcipher.min_keysize;
635                 balg.max_keysize = alg->cra_blkcipher.max_keysize;
636
637                 balg.setkey = async_setkey;
638                 balg.encrypt = async_encrypt;
639                 balg.decrypt = async_decrypt;
640
641                 balg.geniv = alg->cra_blkcipher.geniv;
642         } else {
643                 balg.ivsize = alg->cra_ablkcipher.ivsize;
644                 balg.min_keysize = alg->cra_ablkcipher.min_keysize;
645                 balg.max_keysize = alg->cra_ablkcipher.max_keysize;
646
647                 balg.setkey = alg->cra_ablkcipher.setkey;
648                 balg.encrypt = alg->cra_ablkcipher.encrypt;
649                 balg.decrypt = alg->cra_ablkcipher.decrypt;
650
651                 balg.geniv = alg->cra_ablkcipher.geniv;
652         }
653
654         err = -EINVAL;
655         if (!balg.ivsize)
656                 goto err_drop_alg;
657
658         /*
659          * This is only true if we're constructing an algorithm with its
660          * default IV generator.  For the default generator we elide the
661          * template name and double-check the IV generator.
662          */
663         if (algt->mask & CRYPTO_ALG_GENIV) {
664                 if (!balg.geniv)
665                         balg.geniv = crypto_default_geniv(alg);
666                 err = -EAGAIN;
667                 if (strcmp(tmpl->name, balg.geniv))
668                         goto err_drop_alg;
669
670                 memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
671                 memcpy(inst->alg.cra_driver_name, alg->cra_driver_name,
672                        CRYPTO_MAX_ALG_NAME);
673         } else {
674                 err = -ENAMETOOLONG;
675                 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
676                              "%s(%s)", tmpl->name, alg->cra_name) >=
677                     CRYPTO_MAX_ALG_NAME)
678                         goto err_drop_alg;
679                 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
680                              "%s(%s)", tmpl->name, alg->cra_driver_name) >=
681                     CRYPTO_MAX_ALG_NAME)
682                         goto err_drop_alg;
683         }
684
685         inst->alg.cra_flags = CRYPTO_ALG_TYPE_GIVCIPHER | CRYPTO_ALG_GENIV;
686         inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
687         inst->alg.cra_priority = alg->cra_priority;
688         inst->alg.cra_blocksize = alg->cra_blocksize;
689         inst->alg.cra_alignmask = alg->cra_alignmask;
690         inst->alg.cra_type = &crypto_givcipher_type;
691
692         inst->alg.cra_ablkcipher.ivsize = balg.ivsize;
693         inst->alg.cra_ablkcipher.min_keysize = balg.min_keysize;
694         inst->alg.cra_ablkcipher.max_keysize = balg.max_keysize;
695         inst->alg.cra_ablkcipher.geniv = balg.geniv;
696
697         inst->alg.cra_ablkcipher.setkey = balg.setkey;
698         inst->alg.cra_ablkcipher.encrypt = balg.encrypt;
699         inst->alg.cra_ablkcipher.decrypt = balg.decrypt;
700
701 out:
702         return inst;
703
704 err_drop_alg:
705         crypto_drop_skcipher(spawn);
706 err_free_inst:
707         kfree(inst);
708         inst = ERR_PTR(err);
709         goto out;
710 }
711 EXPORT_SYMBOL_GPL(skcipher_geniv_alloc);
712
713 void skcipher_geniv_free(struct crypto_instance *inst)
714 {
715         crypto_drop_skcipher(crypto_instance_ctx(inst));
716         kfree(inst);
717 }
718 EXPORT_SYMBOL_GPL(skcipher_geniv_free);
719
720 int skcipher_geniv_init(struct crypto_tfm *tfm)
721 {
722         struct crypto_instance *inst = (void *)tfm->__crt_alg;
723         struct crypto_ablkcipher *cipher;
724
725         cipher = crypto_spawn_skcipher(crypto_instance_ctx(inst));
726         if (IS_ERR(cipher))
727                 return PTR_ERR(cipher);
728
729         tfm->crt_ablkcipher.base = cipher;
730         tfm->crt_ablkcipher.reqsize += crypto_ablkcipher_reqsize(cipher);
731
732         return 0;
733 }
734 EXPORT_SYMBOL_GPL(skcipher_geniv_init);
735
736 void skcipher_geniv_exit(struct crypto_tfm *tfm)
737 {
738         crypto_free_ablkcipher(tfm->crt_ablkcipher.base);
739 }
740 EXPORT_SYMBOL_GPL(skcipher_geniv_exit);
741
742 MODULE_LICENSE("GPL");
743 MODULE_DESCRIPTION("Generic block chaining cipher type");