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v4.6
  1/*
  2 * Asynchronous block chaining cipher operations.
  3 *
  4 * This is the asynchronous version of blkcipher.c indicating completion
  5 * via a callback.
  6 *
  7 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
  8 *
  9 * This program is free software; you can redistribute it and/or modify it
 10 * under the terms of the GNU General Public License as published by the Free
 11 * Software Foundation; either version 2 of the License, or (at your option)
 12 * any later version.
 13 *
 14 */
 15
 16#include <crypto/internal/skcipher.h>
 17#include <linux/cpumask.h>
 18#include <linux/err.h>
 19#include <linux/kernel.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 <crypto/scatterwalk.h>
 28
 29#include "internal.h"
 30
 31struct ablkcipher_buffer {
 32	struct list_head	entry;
 33	struct scatter_walk	dst;
 34	unsigned int		len;
 35	void			*data;
 36};
 37
 38enum {
 39	ABLKCIPHER_WALK_SLOW = 1 << 0,
 40};
 41
 42static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
 43{
 44	scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
 45}
 46
 47void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
 48{
 49	struct ablkcipher_buffer *p, *tmp;
 50
 51	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
 52		ablkcipher_buffer_write(p);
 53		list_del(&p->entry);
 54		kfree(p);
 55	}
 56}
 57EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);
 58
 59static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
 60					  struct ablkcipher_buffer *p)
 61{
 62	p->dst = walk->out;
 63	list_add_tail(&p->entry, &walk->buffers);
 64}
 65
 66/* Get a spot of the specified length that does not straddle a page.
 67 * The caller needs to ensure that there is enough space for this operation.
 68 */
 69static inline u8 *ablkcipher_get_spot(u8 *start, unsigned int len)
 70{
 71	u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
 72
 73	return max(start, end_page);
 74}
 75
 76static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
 77						unsigned int bsize)
 78{
 79	unsigned int n = bsize;
 80
 81	for (;;) {
 82		unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
 83
 84		if (len_this_page > n)
 85			len_this_page = n;
 86		scatterwalk_advance(&walk->out, n);
 87		if (n == len_this_page)
 88			break;
 89		n -= len_this_page;
 90		scatterwalk_start(&walk->out, sg_next(walk->out.sg));
 91	}
 92
 93	return bsize;
 94}
 95
 96static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
 97						unsigned int n)
 98{
 99	scatterwalk_advance(&walk->in, n);
100	scatterwalk_advance(&walk->out, n);
101
102	return n;
103}
104
105static int ablkcipher_walk_next(struct ablkcipher_request *req,
106				struct ablkcipher_walk *walk);
107
108int ablkcipher_walk_done(struct ablkcipher_request *req,
109			 struct ablkcipher_walk *walk, int err)
110{
111	struct crypto_tfm *tfm = req->base.tfm;
112	unsigned int nbytes = 0;
113
114	if (likely(err >= 0)) {
115		unsigned int n = walk->nbytes - err;
116
117		if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
118			n = ablkcipher_done_fast(walk, n);
119		else if (WARN_ON(err)) {
120			err = -EINVAL;
121			goto err;
122		} else
123			n = ablkcipher_done_slow(walk, n);
124
125		nbytes = walk->total - n;
126		err = 0;
127	}
128
129	scatterwalk_done(&walk->in, 0, nbytes);
130	scatterwalk_done(&walk->out, 1, nbytes);
131
132err:
133	walk->total = nbytes;
134	walk->nbytes = nbytes;
135
136	if (nbytes) {
137		crypto_yield(req->base.flags);
138		return ablkcipher_walk_next(req, walk);
139	}
140
141	if (walk->iv != req->info)
142		memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
143	kfree(walk->iv_buffer);
144
145	return err;
146}
147EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
148
149static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
150				       struct ablkcipher_walk *walk,
151				       unsigned int bsize,
152				       unsigned int alignmask,
153				       void **src_p, void **dst_p)
154{
155	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
156	struct ablkcipher_buffer *p;
157	void *src, *dst, *base;
158	unsigned int n;
159
160	n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
161	n += (aligned_bsize * 3 - (alignmask + 1) +
162	      (alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
163
164	p = kmalloc(n, GFP_ATOMIC);
165	if (!p)
166		return ablkcipher_walk_done(req, walk, -ENOMEM);
167
168	base = p + 1;
169
170	dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
171	src = dst = ablkcipher_get_spot(dst, bsize);
172
173	p->len = bsize;
174	p->data = dst;
175
176	scatterwalk_copychunks(src, &walk->in, bsize, 0);
177
178	ablkcipher_queue_write(walk, p);
179
180	walk->nbytes = bsize;
181	walk->flags |= ABLKCIPHER_WALK_SLOW;
182
183	*src_p = src;
184	*dst_p = dst;
185
186	return 0;
187}
188
189static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
190				     struct crypto_tfm *tfm,
191				     unsigned int alignmask)
192{
193	unsigned bs = walk->blocksize;
194	unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
195	unsigned aligned_bs = ALIGN(bs, alignmask + 1);
196	unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
197			    (alignmask + 1);
198	u8 *iv;
199
200	size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
201	walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
202	if (!walk->iv_buffer)
203		return -ENOMEM;
204
205	iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
206	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
207	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
208	iv = ablkcipher_get_spot(iv, ivsize);
209
210	walk->iv = memcpy(iv, walk->iv, ivsize);
211	return 0;
212}
213
214static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
215				       struct ablkcipher_walk *walk)
216{
217	walk->src.page = scatterwalk_page(&walk->in);
218	walk->src.offset = offset_in_page(walk->in.offset);
219	walk->dst.page = scatterwalk_page(&walk->out);
220	walk->dst.offset = offset_in_page(walk->out.offset);
221
222	return 0;
223}
224
225static int ablkcipher_walk_next(struct ablkcipher_request *req,
226				struct ablkcipher_walk *walk)
227{
228	struct crypto_tfm *tfm = req->base.tfm;
229	unsigned int alignmask, bsize, n;
230	void *src, *dst;
231	int err;
232
233	alignmask = crypto_tfm_alg_alignmask(tfm);
234	n = walk->total;
235	if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
236		req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
237		return ablkcipher_walk_done(req, walk, -EINVAL);
238	}
239
240	walk->flags &= ~ABLKCIPHER_WALK_SLOW;
241	src = dst = NULL;
242
243	bsize = min(walk->blocksize, n);
244	n = scatterwalk_clamp(&walk->in, n);
245	n = scatterwalk_clamp(&walk->out, n);
246
247	if (n < bsize ||
248	    !scatterwalk_aligned(&walk->in, alignmask) ||
249	    !scatterwalk_aligned(&walk->out, alignmask)) {
250		err = ablkcipher_next_slow(req, walk, bsize, alignmask,
251					   &src, &dst);
252		goto set_phys_lowmem;
253	}
254
255	walk->nbytes = n;
256
257	return ablkcipher_next_fast(req, walk);
258
259set_phys_lowmem:
260	if (err >= 0) {
261		walk->src.page = virt_to_page(src);
262		walk->dst.page = virt_to_page(dst);
263		walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
264		walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
265	}
266
267	return err;
268}
269
270static int ablkcipher_walk_first(struct ablkcipher_request *req,
271				 struct ablkcipher_walk *walk)
272{
273	struct crypto_tfm *tfm = req->base.tfm;
274	unsigned int alignmask;
275
276	alignmask = crypto_tfm_alg_alignmask(tfm);
277	if (WARN_ON_ONCE(in_irq()))
278		return -EDEADLK;
279
280	walk->iv = req->info;
281	walk->nbytes = walk->total;
282	if (unlikely(!walk->total))
283		return 0;
284
285	walk->iv_buffer = NULL;
 
286	if (unlikely(((unsigned long)walk->iv & alignmask))) {
287		int err = ablkcipher_copy_iv(walk, tfm, alignmask);
288
289		if (err)
290			return err;
291	}
292
293	scatterwalk_start(&walk->in, walk->in.sg);
294	scatterwalk_start(&walk->out, walk->out.sg);
295
296	return ablkcipher_walk_next(req, walk);
297}
298
299int ablkcipher_walk_phys(struct ablkcipher_request *req,
300			 struct ablkcipher_walk *walk)
301{
302	walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
303	return ablkcipher_walk_first(req, walk);
304}
305EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
306
307static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
308			    unsigned int keylen)
309{
310	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
311	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
312	int ret;
313	u8 *buffer, *alignbuffer;
314	unsigned long absize;
315
316	absize = keylen + alignmask;
317	buffer = kmalloc(absize, GFP_ATOMIC);
318	if (!buffer)
319		return -ENOMEM;
320
321	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
322	memcpy(alignbuffer, key, keylen);
323	ret = cipher->setkey(tfm, alignbuffer, keylen);
324	memset(alignbuffer, 0, keylen);
325	kfree(buffer);
326	return ret;
327}
328
329static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
330		  unsigned int keylen)
331{
332	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
333	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
334
335	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
336		crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
337		return -EINVAL;
338	}
339
340	if ((unsigned long)key & alignmask)
341		return setkey_unaligned(tfm, key, keylen);
342
343	return cipher->setkey(tfm, key, keylen);
344}
345
346static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
347					      u32 mask)
348{
349	return alg->cra_ctxsize;
350}
351
352int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
353{
354	return crypto_ablkcipher_encrypt(&req->creq);
355}
356
357int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
358{
359	return crypto_ablkcipher_decrypt(&req->creq);
360}
361
362static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
363				      u32 mask)
364{
365	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
366	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
367
368	if (alg->ivsize > PAGE_SIZE / 8)
369		return -EINVAL;
370
371	crt->setkey = setkey;
372	crt->encrypt = alg->encrypt;
373	crt->decrypt = alg->decrypt;
374	if (!alg->ivsize) {
375		crt->givencrypt = skcipher_null_givencrypt;
376		crt->givdecrypt = skcipher_null_givdecrypt;
377	}
378	crt->base = __crypto_ablkcipher_cast(tfm);
379	crt->ivsize = alg->ivsize;
380
381	return 0;
382}
383
384#ifdef CONFIG_NET
385static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
386{
387	struct crypto_report_blkcipher rblkcipher;
388
389	strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
390	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
391		sizeof(rblkcipher.geniv));
392
393	rblkcipher.blocksize = alg->cra_blocksize;
394	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
395	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
396	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
397
398	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
399		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
400		goto nla_put_failure;
401	return 0;
402
403nla_put_failure:
404	return -EMSGSIZE;
405}
406#else
407static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
408{
409	return -ENOSYS;
410}
411#endif
412
413static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
414	__attribute__ ((unused));
415static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
416{
417	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
418
419	seq_printf(m, "type         : ablkcipher\n");
420	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
421					     "yes" : "no");
422	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
423	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
424	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
425	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
426	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<default>");
427}
428
429const struct crypto_type crypto_ablkcipher_type = {
430	.ctxsize = crypto_ablkcipher_ctxsize,
431	.init = crypto_init_ablkcipher_ops,
432#ifdef CONFIG_PROC_FS
433	.show = crypto_ablkcipher_show,
434#endif
435	.report = crypto_ablkcipher_report,
436};
437EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
438
439static int no_givdecrypt(struct skcipher_givcrypt_request *req)
440{
441	return -ENOSYS;
442}
443
444static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
445				      u32 mask)
446{
447	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
448	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
449
450	if (alg->ivsize > PAGE_SIZE / 8)
451		return -EINVAL;
452
453	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
454		      alg->setkey : setkey;
455	crt->encrypt = alg->encrypt;
456	crt->decrypt = alg->decrypt;
457	crt->givencrypt = alg->givencrypt ?: no_givdecrypt;
458	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
459	crt->base = __crypto_ablkcipher_cast(tfm);
460	crt->ivsize = alg->ivsize;
461
462	return 0;
463}
464
465#ifdef CONFIG_NET
466static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
467{
468	struct crypto_report_blkcipher rblkcipher;
469
470	strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
471	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
472		sizeof(rblkcipher.geniv));
473
474	rblkcipher.blocksize = alg->cra_blocksize;
475	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
476	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
477	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
478
479	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
480		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
481		goto nla_put_failure;
482	return 0;
483
484nla_put_failure:
485	return -EMSGSIZE;
486}
487#else
488static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
489{
490	return -ENOSYS;
491}
492#endif
493
494static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
495	__attribute__ ((unused));
496static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
497{
498	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
499
500	seq_printf(m, "type         : givcipher\n");
501	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
502					     "yes" : "no");
503	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
504	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
505	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
506	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
507	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<built-in>");
508}
509
510const struct crypto_type crypto_givcipher_type = {
511	.ctxsize = crypto_ablkcipher_ctxsize,
512	.init = crypto_init_givcipher_ops,
513#ifdef CONFIG_PROC_FS
514	.show = crypto_givcipher_show,
515#endif
516	.report = crypto_givcipher_report,
517};
518EXPORT_SYMBOL_GPL(crypto_givcipher_type);
519
520const char *crypto_default_geniv(const struct crypto_alg *alg)
521{
522	if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
523	     CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
524					 alg->cra_ablkcipher.ivsize) !=
525	    alg->cra_blocksize)
526		return "chainiv";
527
528	return "eseqiv";
529}
530
531static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
532{
533	struct rtattr *tb[3];
534	struct {
535		struct rtattr attr;
536		struct crypto_attr_type data;
537	} ptype;
538	struct {
539		struct rtattr attr;
540		struct crypto_attr_alg data;
541	} palg;
542	struct crypto_template *tmpl;
543	struct crypto_instance *inst;
544	struct crypto_alg *larval;
545	const char *geniv;
546	int err;
547
548	larval = crypto_larval_lookup(alg->cra_driver_name,
549				      (type & ~CRYPTO_ALG_TYPE_MASK) |
550				      CRYPTO_ALG_TYPE_GIVCIPHER,
551				      mask | CRYPTO_ALG_TYPE_MASK);
552	err = PTR_ERR(larval);
553	if (IS_ERR(larval))
554		goto out;
555
556	err = -EAGAIN;
557	if (!crypto_is_larval(larval))
558		goto drop_larval;
559
560	ptype.attr.rta_len = sizeof(ptype);
561	ptype.attr.rta_type = CRYPTOA_TYPE;
562	ptype.data.type = type | CRYPTO_ALG_GENIV;
563	/* GENIV tells the template that we're making a default geniv. */
564	ptype.data.mask = mask | CRYPTO_ALG_GENIV;
565	tb[0] = &ptype.attr;
566
567	palg.attr.rta_len = sizeof(palg);
568	palg.attr.rta_type = CRYPTOA_ALG;
569	/* Must use the exact name to locate ourselves. */
570	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
571	tb[1] = &palg.attr;
572
573	tb[2] = NULL;
574
575	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
576	    CRYPTO_ALG_TYPE_BLKCIPHER)
577		geniv = alg->cra_blkcipher.geniv;
578	else
579		geniv = alg->cra_ablkcipher.geniv;
580
581	if (!geniv)
582		geniv = crypto_default_geniv(alg);
583
584	tmpl = crypto_lookup_template(geniv);
585	err = -ENOENT;
586	if (!tmpl)
587		goto kill_larval;
588
589	if (tmpl->create) {
590		err = tmpl->create(tmpl, tb);
591		if (err)
592			goto put_tmpl;
593		goto ok;
594	}
595
596	inst = tmpl->alloc(tb);
597	err = PTR_ERR(inst);
598	if (IS_ERR(inst))
599		goto put_tmpl;
600
601	err = crypto_register_instance(tmpl, inst);
602	if (err) {
603		tmpl->free(inst);
604		goto put_tmpl;
605	}
606
607ok:
608	/* Redo the lookup to use the instance we just registered. */
609	err = -EAGAIN;
610
611put_tmpl:
612	crypto_tmpl_put(tmpl);
613kill_larval:
614	crypto_larval_kill(larval);
615drop_larval:
616	crypto_mod_put(larval);
617out:
618	crypto_mod_put(alg);
619	return err;
620}
621
622struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, u32 mask)
623{
624	struct crypto_alg *alg;
625
626	alg = crypto_alg_mod_lookup(name, type, mask);
627	if (IS_ERR(alg))
628		return alg;
629
630	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
631	    CRYPTO_ALG_TYPE_GIVCIPHER)
632		return alg;
633
634	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
635	      CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
636					  alg->cra_ablkcipher.ivsize))
637		return alg;
638
639	crypto_mod_put(alg);
640	alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
641				    mask & ~CRYPTO_ALG_TESTED);
642	if (IS_ERR(alg))
643		return alg;
644
645	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
646	    CRYPTO_ALG_TYPE_GIVCIPHER) {
647		if (~alg->cra_flags & (type ^ ~mask) & CRYPTO_ALG_TESTED) {
648			crypto_mod_put(alg);
649			alg = ERR_PTR(-ENOENT);
650		}
651		return alg;
652	}
653
654	BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
655		 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
656					     alg->cra_ablkcipher.ivsize));
657
658	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
659}
660EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);
661
662int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
663			 u32 type, u32 mask)
664{
665	struct crypto_alg *alg;
666	int err;
667
668	type = crypto_skcipher_type(type);
669	mask = crypto_skcipher_mask(mask);
670
671	alg = crypto_lookup_skcipher(name, type, mask);
672	if (IS_ERR(alg))
673		return PTR_ERR(alg);
674
675	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
676	crypto_mod_put(alg);
677	return err;
678}
679EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
680
681struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
682						  u32 type, u32 mask)
683{
684	struct crypto_tfm *tfm;
685	int err;
686
687	type = crypto_skcipher_type(type);
688	mask = crypto_skcipher_mask(mask);
689
690	for (;;) {
691		struct crypto_alg *alg;
692
693		alg = crypto_lookup_skcipher(alg_name, type, mask);
694		if (IS_ERR(alg)) {
695			err = PTR_ERR(alg);
696			goto err;
697		}
698
699		tfm = __crypto_alloc_tfm(alg, type, mask);
700		if (!IS_ERR(tfm))
701			return __crypto_ablkcipher_cast(tfm);
702
703		crypto_mod_put(alg);
704		err = PTR_ERR(tfm);
705
706err:
707		if (err != -EAGAIN)
708			break;
709		if (fatal_signal_pending(current)) {
710			err = -EINTR;
711			break;
712		}
713	}
714
715	return ERR_PTR(err);
716}
717EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);
v3.15
  1/*
  2 * Asynchronous block chaining cipher operations.
  3 *
  4 * This is the asynchronous version of blkcipher.c indicating completion
  5 * via a callback.
  6 *
  7 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
  8 *
  9 * This program is free software; you can redistribute it and/or modify it
 10 * under the terms of the GNU General Public License as published by the Free
 11 * Software Foundation; either version 2 of the License, or (at your option)
 12 * any later version.
 13 *
 14 */
 15
 16#include <crypto/internal/skcipher.h>
 17#include <linux/cpumask.h>
 18#include <linux/err.h>
 19#include <linux/kernel.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 <crypto/scatterwalk.h>
 28
 29#include "internal.h"
 30
 31struct ablkcipher_buffer {
 32	struct list_head	entry;
 33	struct scatter_walk	dst;
 34	unsigned int		len;
 35	void			*data;
 36};
 37
 38enum {
 39	ABLKCIPHER_WALK_SLOW = 1 << 0,
 40};
 41
 42static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
 43{
 44	scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
 45}
 46
 47void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
 48{
 49	struct ablkcipher_buffer *p, *tmp;
 50
 51	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
 52		ablkcipher_buffer_write(p);
 53		list_del(&p->entry);
 54		kfree(p);
 55	}
 56}
 57EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);
 58
 59static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
 60					  struct ablkcipher_buffer *p)
 61{
 62	p->dst = walk->out;
 63	list_add_tail(&p->entry, &walk->buffers);
 64}
 65
 66/* Get a spot of the specified length that does not straddle a page.
 67 * The caller needs to ensure that there is enough space for this operation.
 68 */
 69static inline u8 *ablkcipher_get_spot(u8 *start, unsigned int len)
 70{
 71	u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
 
 72	return max(start, end_page);
 73}
 74
 75static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
 76						unsigned int bsize)
 77{
 78	unsigned int n = bsize;
 79
 80	for (;;) {
 81		unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
 82
 83		if (len_this_page > n)
 84			len_this_page = n;
 85		scatterwalk_advance(&walk->out, n);
 86		if (n == len_this_page)
 87			break;
 88		n -= len_this_page;
 89		scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg));
 90	}
 91
 92	return bsize;
 93}
 94
 95static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
 96						unsigned int n)
 97{
 98	scatterwalk_advance(&walk->in, n);
 99	scatterwalk_advance(&walk->out, n);
100
101	return n;
102}
103
104static int ablkcipher_walk_next(struct ablkcipher_request *req,
105				struct ablkcipher_walk *walk);
106
107int ablkcipher_walk_done(struct ablkcipher_request *req,
108			 struct ablkcipher_walk *walk, int err)
109{
110	struct crypto_tfm *tfm = req->base.tfm;
111	unsigned int nbytes = 0;
112
113	if (likely(err >= 0)) {
114		unsigned int n = walk->nbytes - err;
115
116		if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
117			n = ablkcipher_done_fast(walk, n);
118		else if (WARN_ON(err)) {
119			err = -EINVAL;
120			goto err;
121		} else
122			n = ablkcipher_done_slow(walk, n);
123
124		nbytes = walk->total - n;
125		err = 0;
126	}
127
128	scatterwalk_done(&walk->in, 0, nbytes);
129	scatterwalk_done(&walk->out, 1, nbytes);
130
131err:
132	walk->total = nbytes;
133	walk->nbytes = nbytes;
134
135	if (nbytes) {
136		crypto_yield(req->base.flags);
137		return ablkcipher_walk_next(req, walk);
138	}
139
140	if (walk->iv != req->info)
141		memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
142	kfree(walk->iv_buffer);
143
144	return err;
145}
146EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
147
148static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
149				       struct ablkcipher_walk *walk,
150				       unsigned int bsize,
151				       unsigned int alignmask,
152				       void **src_p, void **dst_p)
153{
154	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
155	struct ablkcipher_buffer *p;
156	void *src, *dst, *base;
157	unsigned int n;
158
159	n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
160	n += (aligned_bsize * 3 - (alignmask + 1) +
161	      (alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
162
163	p = kmalloc(n, GFP_ATOMIC);
164	if (!p)
165		return ablkcipher_walk_done(req, walk, -ENOMEM);
166
167	base = p + 1;
168
169	dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
170	src = dst = ablkcipher_get_spot(dst, bsize);
171
172	p->len = bsize;
173	p->data = dst;
174
175	scatterwalk_copychunks(src, &walk->in, bsize, 0);
176
177	ablkcipher_queue_write(walk, p);
178
179	walk->nbytes = bsize;
180	walk->flags |= ABLKCIPHER_WALK_SLOW;
181
182	*src_p = src;
183	*dst_p = dst;
184
185	return 0;
186}
187
188static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
189				     struct crypto_tfm *tfm,
190				     unsigned int alignmask)
191{
192	unsigned bs = walk->blocksize;
193	unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
194	unsigned aligned_bs = ALIGN(bs, alignmask + 1);
195	unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
196			    (alignmask + 1);
197	u8 *iv;
198
199	size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
200	walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
201	if (!walk->iv_buffer)
202		return -ENOMEM;
203
204	iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
205	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
206	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
207	iv = ablkcipher_get_spot(iv, ivsize);
208
209	walk->iv = memcpy(iv, walk->iv, ivsize);
210	return 0;
211}
212
213static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
214				       struct ablkcipher_walk *walk)
215{
216	walk->src.page = scatterwalk_page(&walk->in);
217	walk->src.offset = offset_in_page(walk->in.offset);
218	walk->dst.page = scatterwalk_page(&walk->out);
219	walk->dst.offset = offset_in_page(walk->out.offset);
220
221	return 0;
222}
223
224static int ablkcipher_walk_next(struct ablkcipher_request *req,
225				struct ablkcipher_walk *walk)
226{
227	struct crypto_tfm *tfm = req->base.tfm;
228	unsigned int alignmask, bsize, n;
229	void *src, *dst;
230	int err;
231
232	alignmask = crypto_tfm_alg_alignmask(tfm);
233	n = walk->total;
234	if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
235		req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
236		return ablkcipher_walk_done(req, walk, -EINVAL);
237	}
238
239	walk->flags &= ~ABLKCIPHER_WALK_SLOW;
240	src = dst = NULL;
241
242	bsize = min(walk->blocksize, n);
243	n = scatterwalk_clamp(&walk->in, n);
244	n = scatterwalk_clamp(&walk->out, n);
245
246	if (n < bsize ||
247	    !scatterwalk_aligned(&walk->in, alignmask) ||
248	    !scatterwalk_aligned(&walk->out, alignmask)) {
249		err = ablkcipher_next_slow(req, walk, bsize, alignmask,
250					   &src, &dst);
251		goto set_phys_lowmem;
252	}
253
254	walk->nbytes = n;
255
256	return ablkcipher_next_fast(req, walk);
257
258set_phys_lowmem:
259	if (err >= 0) {
260		walk->src.page = virt_to_page(src);
261		walk->dst.page = virt_to_page(dst);
262		walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
263		walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
264	}
265
266	return err;
267}
268
269static int ablkcipher_walk_first(struct ablkcipher_request *req,
270				 struct ablkcipher_walk *walk)
271{
272	struct crypto_tfm *tfm = req->base.tfm;
273	unsigned int alignmask;
274
275	alignmask = crypto_tfm_alg_alignmask(tfm);
276	if (WARN_ON_ONCE(in_irq()))
277		return -EDEADLK;
278
 
279	walk->nbytes = walk->total;
280	if (unlikely(!walk->total))
281		return 0;
282
283	walk->iv_buffer = NULL;
284	walk->iv = req->info;
285	if (unlikely(((unsigned long)walk->iv & alignmask))) {
286		int err = ablkcipher_copy_iv(walk, tfm, alignmask);
 
287		if (err)
288			return err;
289	}
290
291	scatterwalk_start(&walk->in, walk->in.sg);
292	scatterwalk_start(&walk->out, walk->out.sg);
293
294	return ablkcipher_walk_next(req, walk);
295}
296
297int ablkcipher_walk_phys(struct ablkcipher_request *req,
298			 struct ablkcipher_walk *walk)
299{
300	walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
301	return ablkcipher_walk_first(req, walk);
302}
303EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
304
305static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
306			    unsigned int keylen)
307{
308	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
309	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
310	int ret;
311	u8 *buffer, *alignbuffer;
312	unsigned long absize;
313
314	absize = keylen + alignmask;
315	buffer = kmalloc(absize, GFP_ATOMIC);
316	if (!buffer)
317		return -ENOMEM;
318
319	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
320	memcpy(alignbuffer, key, keylen);
321	ret = cipher->setkey(tfm, alignbuffer, keylen);
322	memset(alignbuffer, 0, keylen);
323	kfree(buffer);
324	return ret;
325}
326
327static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
328		  unsigned int keylen)
329{
330	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
331	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
332
333	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
334		crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
335		return -EINVAL;
336	}
337
338	if ((unsigned long)key & alignmask)
339		return setkey_unaligned(tfm, key, keylen);
340
341	return cipher->setkey(tfm, key, keylen);
342}
343
344static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
345					      u32 mask)
346{
347	return alg->cra_ctxsize;
348}
349
350int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
351{
352	return crypto_ablkcipher_encrypt(&req->creq);
353}
354
355int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
356{
357	return crypto_ablkcipher_decrypt(&req->creq);
358}
359
360static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
361				      u32 mask)
362{
363	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
364	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
365
366	if (alg->ivsize > PAGE_SIZE / 8)
367		return -EINVAL;
368
369	crt->setkey = setkey;
370	crt->encrypt = alg->encrypt;
371	crt->decrypt = alg->decrypt;
372	if (!alg->ivsize) {
373		crt->givencrypt = skcipher_null_givencrypt;
374		crt->givdecrypt = skcipher_null_givdecrypt;
375	}
376	crt->base = __crypto_ablkcipher_cast(tfm);
377	crt->ivsize = alg->ivsize;
378
379	return 0;
380}
381
382#ifdef CONFIG_NET
383static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
384{
385	struct crypto_report_blkcipher rblkcipher;
386
387	strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
388	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
389		sizeof(rblkcipher.geniv));
390
391	rblkcipher.blocksize = alg->cra_blocksize;
392	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
393	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
394	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
395
396	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
397		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
398		goto nla_put_failure;
399	return 0;
400
401nla_put_failure:
402	return -EMSGSIZE;
403}
404#else
405static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
406{
407	return -ENOSYS;
408}
409#endif
410
411static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
412	__attribute__ ((unused));
413static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
414{
415	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
416
417	seq_printf(m, "type         : ablkcipher\n");
418	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
419					     "yes" : "no");
420	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
421	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
422	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
423	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
424	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<default>");
425}
426
427const struct crypto_type crypto_ablkcipher_type = {
428	.ctxsize = crypto_ablkcipher_ctxsize,
429	.init = crypto_init_ablkcipher_ops,
430#ifdef CONFIG_PROC_FS
431	.show = crypto_ablkcipher_show,
432#endif
433	.report = crypto_ablkcipher_report,
434};
435EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
436
437static int no_givdecrypt(struct skcipher_givcrypt_request *req)
438{
439	return -ENOSYS;
440}
441
442static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
443				      u32 mask)
444{
445	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
446	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
447
448	if (alg->ivsize > PAGE_SIZE / 8)
449		return -EINVAL;
450
451	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
452		      alg->setkey : setkey;
453	crt->encrypt = alg->encrypt;
454	crt->decrypt = alg->decrypt;
455	crt->givencrypt = alg->givencrypt;
456	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
457	crt->base = __crypto_ablkcipher_cast(tfm);
458	crt->ivsize = alg->ivsize;
459
460	return 0;
461}
462
463#ifdef CONFIG_NET
464static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
465{
466	struct crypto_report_blkcipher rblkcipher;
467
468	strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
469	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
470		sizeof(rblkcipher.geniv));
471
472	rblkcipher.blocksize = alg->cra_blocksize;
473	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
474	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
475	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
476
477	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
478		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
479		goto nla_put_failure;
480	return 0;
481
482nla_put_failure:
483	return -EMSGSIZE;
484}
485#else
486static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
487{
488	return -ENOSYS;
489}
490#endif
491
492static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
493	__attribute__ ((unused));
494static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
495{
496	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
497
498	seq_printf(m, "type         : givcipher\n");
499	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
500					     "yes" : "no");
501	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
502	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
503	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
504	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
505	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<built-in>");
506}
507
508const struct crypto_type crypto_givcipher_type = {
509	.ctxsize = crypto_ablkcipher_ctxsize,
510	.init = crypto_init_givcipher_ops,
511#ifdef CONFIG_PROC_FS
512	.show = crypto_givcipher_show,
513#endif
514	.report = crypto_givcipher_report,
515};
516EXPORT_SYMBOL_GPL(crypto_givcipher_type);
517
518const char *crypto_default_geniv(const struct crypto_alg *alg)
519{
520	if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
521	     CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
522					 alg->cra_ablkcipher.ivsize) !=
523	    alg->cra_blocksize)
524		return "chainiv";
525
526	return "eseqiv";
527}
528
529static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
530{
531	struct rtattr *tb[3];
532	struct {
533		struct rtattr attr;
534		struct crypto_attr_type data;
535	} ptype;
536	struct {
537		struct rtattr attr;
538		struct crypto_attr_alg data;
539	} palg;
540	struct crypto_template *tmpl;
541	struct crypto_instance *inst;
542	struct crypto_alg *larval;
543	const char *geniv;
544	int err;
545
546	larval = crypto_larval_lookup(alg->cra_driver_name,
547				      (type & ~CRYPTO_ALG_TYPE_MASK) |
548				      CRYPTO_ALG_TYPE_GIVCIPHER,
549				      mask | CRYPTO_ALG_TYPE_MASK);
550	err = PTR_ERR(larval);
551	if (IS_ERR(larval))
552		goto out;
553
554	err = -EAGAIN;
555	if (!crypto_is_larval(larval))
556		goto drop_larval;
557
558	ptype.attr.rta_len = sizeof(ptype);
559	ptype.attr.rta_type = CRYPTOA_TYPE;
560	ptype.data.type = type | CRYPTO_ALG_GENIV;
561	/* GENIV tells the template that we're making a default geniv. */
562	ptype.data.mask = mask | CRYPTO_ALG_GENIV;
563	tb[0] = &ptype.attr;
564
565	palg.attr.rta_len = sizeof(palg);
566	palg.attr.rta_type = CRYPTOA_ALG;
567	/* Must use the exact name to locate ourselves. */
568	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
569	tb[1] = &palg.attr;
570
571	tb[2] = NULL;
572
573	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
574	    CRYPTO_ALG_TYPE_BLKCIPHER)
575		geniv = alg->cra_blkcipher.geniv;
576	else
577		geniv = alg->cra_ablkcipher.geniv;
578
579	if (!geniv)
580		geniv = crypto_default_geniv(alg);
581
582	tmpl = crypto_lookup_template(geniv);
583	err = -ENOENT;
584	if (!tmpl)
585		goto kill_larval;
586
 
 
 
 
 
 
 
587	inst = tmpl->alloc(tb);
588	err = PTR_ERR(inst);
589	if (IS_ERR(inst))
590		goto put_tmpl;
591
592	if ((err = crypto_register_instance(tmpl, inst))) {
 
593		tmpl->free(inst);
594		goto put_tmpl;
595	}
596
 
597	/* Redo the lookup to use the instance we just registered. */
598	err = -EAGAIN;
599
600put_tmpl:
601	crypto_tmpl_put(tmpl);
602kill_larval:
603	crypto_larval_kill(larval);
604drop_larval:
605	crypto_mod_put(larval);
606out:
607	crypto_mod_put(alg);
608	return err;
609}
610
611struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, u32 mask)
612{
613	struct crypto_alg *alg;
614
615	alg = crypto_alg_mod_lookup(name, type, mask);
616	if (IS_ERR(alg))
617		return alg;
618
619	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
620	    CRYPTO_ALG_TYPE_GIVCIPHER)
621		return alg;
622
623	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
624	      CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
625					  alg->cra_ablkcipher.ivsize))
626		return alg;
627
628	crypto_mod_put(alg);
629	alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
630				    mask & ~CRYPTO_ALG_TESTED);
631	if (IS_ERR(alg))
632		return alg;
633
634	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
635	    CRYPTO_ALG_TYPE_GIVCIPHER) {
636		if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
637			crypto_mod_put(alg);
638			alg = ERR_PTR(-ENOENT);
639		}
640		return alg;
641	}
642
643	BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
644		 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
645					     alg->cra_ablkcipher.ivsize));
646
647	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
648}
649EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);
650
651int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
652			 u32 type, u32 mask)
653{
654	struct crypto_alg *alg;
655	int err;
656
657	type = crypto_skcipher_type(type);
658	mask = crypto_skcipher_mask(mask);
659
660	alg = crypto_lookup_skcipher(name, type, mask);
661	if (IS_ERR(alg))
662		return PTR_ERR(alg);
663
664	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
665	crypto_mod_put(alg);
666	return err;
667}
668EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
669
670struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
671						  u32 type, u32 mask)
672{
673	struct crypto_tfm *tfm;
674	int err;
675
676	type = crypto_skcipher_type(type);
677	mask = crypto_skcipher_mask(mask);
678
679	for (;;) {
680		struct crypto_alg *alg;
681
682		alg = crypto_lookup_skcipher(alg_name, type, mask);
683		if (IS_ERR(alg)) {
684			err = PTR_ERR(alg);
685			goto err;
686		}
687
688		tfm = __crypto_alloc_tfm(alg, type, mask);
689		if (!IS_ERR(tfm))
690			return __crypto_ablkcipher_cast(tfm);
691
692		crypto_mod_put(alg);
693		err = PTR_ERR(tfm);
694
695err:
696		if (err != -EAGAIN)
697			break;
698		if (signal_pending(current)) {
699			err = -EINTR;
700			break;
701		}
702	}
703
704	return ERR_PTR(err);
705}
706EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);