x86/speculation/mds: Fix documentation typo
[linux/fpc-iii.git] / crypto / ahash.c
blob5a9fa1a867f9de7adb514a729889b3f6d74871e1
1 /*
2 * Asynchronous Cryptographic Hash operations.
4 * This is the asynchronous version of hash.c with notification of
5 * completion via a callback.
7 * Copyright (c) 2008 Loc Ho <lho@amcc.com>
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.
16 #include <crypto/internal/hash.h>
17 #include <crypto/scatterwalk.h>
18 #include <linux/bug.h>
19 #include <linux/err.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/slab.h>
24 #include <linux/seq_file.h>
25 #include <linux/cryptouser.h>
26 #include <linux/compiler.h>
27 #include <net/netlink.h>
29 #include "internal.h"
31 struct ahash_request_priv {
32 crypto_completion_t complete;
33 void *data;
34 u8 *result;
35 u32 flags;
36 void *ubuf[] CRYPTO_MINALIGN_ATTR;
39 static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash)
41 return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
42 halg);
45 static int hash_walk_next(struct crypto_hash_walk *walk)
47 unsigned int alignmask = walk->alignmask;
48 unsigned int offset = walk->offset;
49 unsigned int nbytes = min(walk->entrylen,
50 ((unsigned int)(PAGE_SIZE)) - offset);
52 if (walk->flags & CRYPTO_ALG_ASYNC)
53 walk->data = kmap(walk->pg);
54 else
55 walk->data = kmap_atomic(walk->pg);
56 walk->data += offset;
58 if (offset & alignmask) {
59 unsigned int unaligned = alignmask + 1 - (offset & alignmask);
61 if (nbytes > unaligned)
62 nbytes = unaligned;
65 walk->entrylen -= nbytes;
66 return nbytes;
69 static int hash_walk_new_entry(struct crypto_hash_walk *walk)
71 struct scatterlist *sg;
73 sg = walk->sg;
74 walk->offset = sg->offset;
75 walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
76 walk->offset = offset_in_page(walk->offset);
77 walk->entrylen = sg->length;
79 if (walk->entrylen > walk->total)
80 walk->entrylen = walk->total;
81 walk->total -= walk->entrylen;
83 return hash_walk_next(walk);
86 int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
88 unsigned int alignmask = walk->alignmask;
90 walk->data -= walk->offset;
92 if (walk->entrylen && (walk->offset & alignmask) && !err) {
93 unsigned int nbytes;
95 walk->offset = ALIGN(walk->offset, alignmask + 1);
96 nbytes = min(walk->entrylen,
97 (unsigned int)(PAGE_SIZE - walk->offset));
98 if (nbytes) {
99 walk->entrylen -= nbytes;
100 walk->data += walk->offset;
101 return nbytes;
105 if (walk->flags & CRYPTO_ALG_ASYNC)
106 kunmap(walk->pg);
107 else {
108 kunmap_atomic(walk->data);
110 * The may sleep test only makes sense for sync users.
111 * Async users don't need to sleep here anyway.
113 crypto_yield(walk->flags);
116 if (err)
117 return err;
119 if (walk->entrylen) {
120 walk->offset = 0;
121 walk->pg++;
122 return hash_walk_next(walk);
125 if (!walk->total)
126 return 0;
128 walk->sg = sg_next(walk->sg);
130 return hash_walk_new_entry(walk);
132 EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
134 int crypto_hash_walk_first(struct ahash_request *req,
135 struct crypto_hash_walk *walk)
137 walk->total = req->nbytes;
139 if (!walk->total) {
140 walk->entrylen = 0;
141 return 0;
144 walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
145 walk->sg = req->src;
146 walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
148 return hash_walk_new_entry(walk);
150 EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
152 int crypto_ahash_walk_first(struct ahash_request *req,
153 struct crypto_hash_walk *walk)
155 walk->total = req->nbytes;
157 if (!walk->total) {
158 walk->entrylen = 0;
159 return 0;
162 walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
163 walk->sg = req->src;
164 walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
165 walk->flags |= CRYPTO_ALG_ASYNC;
167 BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
169 return hash_walk_new_entry(walk);
171 EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
173 static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
174 unsigned int keylen)
176 unsigned long alignmask = crypto_ahash_alignmask(tfm);
177 int ret;
178 u8 *buffer, *alignbuffer;
179 unsigned long absize;
181 absize = keylen + alignmask;
182 buffer = kmalloc(absize, GFP_KERNEL);
183 if (!buffer)
184 return -ENOMEM;
186 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
187 memcpy(alignbuffer, key, keylen);
188 ret = tfm->setkey(tfm, alignbuffer, keylen);
189 kzfree(buffer);
190 return ret;
193 static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
194 unsigned int keylen)
196 return -ENOSYS;
199 static void ahash_set_needkey(struct crypto_ahash *tfm)
201 const struct hash_alg_common *alg = crypto_hash_alg_common(tfm);
203 if (tfm->setkey != ahash_nosetkey &&
204 !(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
205 crypto_ahash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
208 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
209 unsigned int keylen)
211 unsigned long alignmask = crypto_ahash_alignmask(tfm);
212 int err;
214 if ((unsigned long)key & alignmask)
215 err = ahash_setkey_unaligned(tfm, key, keylen);
216 else
217 err = tfm->setkey(tfm, key, keylen);
219 if (unlikely(err)) {
220 ahash_set_needkey(tfm);
221 return err;
224 crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
225 return 0;
227 EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
229 static inline unsigned int ahash_align_buffer_size(unsigned len,
230 unsigned long mask)
232 return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
235 static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
237 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
238 unsigned long alignmask = crypto_ahash_alignmask(tfm);
239 unsigned int ds = crypto_ahash_digestsize(tfm);
240 struct ahash_request_priv *priv;
242 priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
243 (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
244 GFP_KERNEL : GFP_ATOMIC);
245 if (!priv)
246 return -ENOMEM;
249 * WARNING: Voodoo programming below!
251 * The code below is obscure and hard to understand, thus explanation
252 * is necessary. See include/crypto/hash.h and include/linux/crypto.h
253 * to understand the layout of structures used here!
255 * The code here will replace portions of the ORIGINAL request with
256 * pointers to new code and buffers so the hashing operation can store
257 * the result in aligned buffer. We will call the modified request
258 * an ADJUSTED request.
260 * The newly mangled request will look as such:
262 * req {
263 * .result = ADJUSTED[new aligned buffer]
264 * .base.complete = ADJUSTED[pointer to completion function]
265 * .base.data = ADJUSTED[*req (pointer to self)]
266 * .priv = ADJUSTED[new priv] {
267 * .result = ORIGINAL(result)
268 * .complete = ORIGINAL(base.complete)
269 * .data = ORIGINAL(base.data)
273 priv->result = req->result;
274 priv->complete = req->base.complete;
275 priv->data = req->base.data;
276 priv->flags = req->base.flags;
279 * WARNING: We do not backup req->priv here! The req->priv
280 * is for internal use of the Crypto API and the
281 * user must _NOT_ _EVER_ depend on it's content!
284 req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
285 req->base.complete = cplt;
286 req->base.data = req;
287 req->priv = priv;
289 return 0;
292 static void ahash_restore_req(struct ahash_request *req, int err)
294 struct ahash_request_priv *priv = req->priv;
296 if (!err)
297 memcpy(priv->result, req->result,
298 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
300 /* Restore the original crypto request. */
301 req->result = priv->result;
303 ahash_request_set_callback(req, priv->flags,
304 priv->complete, priv->data);
305 req->priv = NULL;
307 /* Free the req->priv.priv from the ADJUSTED request. */
308 kzfree(priv);
311 static void ahash_notify_einprogress(struct ahash_request *req)
313 struct ahash_request_priv *priv = req->priv;
314 struct crypto_async_request oreq;
316 oreq.data = priv->data;
318 priv->complete(&oreq, -EINPROGRESS);
321 static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
323 struct ahash_request *areq = req->data;
325 if (err == -EINPROGRESS) {
326 ahash_notify_einprogress(areq);
327 return;
331 * Restore the original request, see ahash_op_unaligned() for what
332 * goes where.
334 * The "struct ahash_request *req" here is in fact the "req.base"
335 * from the ADJUSTED request from ahash_op_unaligned(), thus as it
336 * is a pointer to self, it is also the ADJUSTED "req" .
339 /* First copy req->result into req->priv.result */
340 ahash_restore_req(areq, err);
342 /* Complete the ORIGINAL request. */
343 areq->base.complete(&areq->base, err);
346 static int ahash_op_unaligned(struct ahash_request *req,
347 int (*op)(struct ahash_request *))
349 int err;
351 err = ahash_save_req(req, ahash_op_unaligned_done);
352 if (err)
353 return err;
355 err = op(req);
356 if (err == -EINPROGRESS ||
357 (err == -EBUSY && (ahash_request_flags(req) &
358 CRYPTO_TFM_REQ_MAY_BACKLOG)))
359 return err;
361 ahash_restore_req(req, err);
363 return err;
366 static int crypto_ahash_op(struct ahash_request *req,
367 int (*op)(struct ahash_request *))
369 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
370 unsigned long alignmask = crypto_ahash_alignmask(tfm);
372 if ((unsigned long)req->result & alignmask)
373 return ahash_op_unaligned(req, op);
375 return op(req);
378 int crypto_ahash_final(struct ahash_request *req)
380 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
382 EXPORT_SYMBOL_GPL(crypto_ahash_final);
384 int crypto_ahash_finup(struct ahash_request *req)
386 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
388 EXPORT_SYMBOL_GPL(crypto_ahash_finup);
390 int crypto_ahash_digest(struct ahash_request *req)
392 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
394 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
395 return -ENOKEY;
397 return crypto_ahash_op(req, tfm->digest);
399 EXPORT_SYMBOL_GPL(crypto_ahash_digest);
401 static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
403 struct ahash_request *areq = req->data;
405 if (err == -EINPROGRESS)
406 return;
408 ahash_restore_req(areq, err);
410 areq->base.complete(&areq->base, err);
413 static int ahash_def_finup_finish1(struct ahash_request *req, int err)
415 if (err)
416 goto out;
418 req->base.complete = ahash_def_finup_done2;
420 err = crypto_ahash_reqtfm(req)->final(req);
421 if (err == -EINPROGRESS ||
422 (err == -EBUSY && (ahash_request_flags(req) &
423 CRYPTO_TFM_REQ_MAY_BACKLOG)))
424 return err;
426 out:
427 ahash_restore_req(req, err);
428 return err;
431 static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
433 struct ahash_request *areq = req->data;
435 if (err == -EINPROGRESS) {
436 ahash_notify_einprogress(areq);
437 return;
440 areq->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
442 err = ahash_def_finup_finish1(areq, err);
443 if (areq->priv)
444 return;
446 areq->base.complete(&areq->base, err);
449 static int ahash_def_finup(struct ahash_request *req)
451 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
452 int err;
454 err = ahash_save_req(req, ahash_def_finup_done1);
455 if (err)
456 return err;
458 err = tfm->update(req);
459 if (err == -EINPROGRESS ||
460 (err == -EBUSY && (ahash_request_flags(req) &
461 CRYPTO_TFM_REQ_MAY_BACKLOG)))
462 return err;
464 return ahash_def_finup_finish1(req, err);
467 static int ahash_no_export(struct ahash_request *req, void *out)
469 return -ENOSYS;
472 static int ahash_no_import(struct ahash_request *req, const void *in)
474 return -ENOSYS;
477 static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
479 struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
480 struct ahash_alg *alg = crypto_ahash_alg(hash);
482 hash->setkey = ahash_nosetkey;
483 hash->export = ahash_no_export;
484 hash->import = ahash_no_import;
486 if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
487 return crypto_init_shash_ops_async(tfm);
489 hash->init = alg->init;
490 hash->update = alg->update;
491 hash->final = alg->final;
492 hash->finup = alg->finup ?: ahash_def_finup;
493 hash->digest = alg->digest;
495 if (alg->setkey) {
496 hash->setkey = alg->setkey;
497 ahash_set_needkey(hash);
499 if (alg->export)
500 hash->export = alg->export;
501 if (alg->import)
502 hash->import = alg->import;
504 return 0;
507 static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
509 if (alg->cra_type != &crypto_ahash_type)
510 return sizeof(struct crypto_shash *);
512 return crypto_alg_extsize(alg);
515 #ifdef CONFIG_NET
516 static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
518 struct crypto_report_hash rhash;
520 strncpy(rhash.type, "ahash", sizeof(rhash.type));
522 rhash.blocksize = alg->cra_blocksize;
523 rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
525 if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
526 sizeof(struct crypto_report_hash), &rhash))
527 goto nla_put_failure;
528 return 0;
530 nla_put_failure:
531 return -EMSGSIZE;
533 #else
534 static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
536 return -ENOSYS;
538 #endif
540 static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
541 __maybe_unused;
542 static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
544 seq_printf(m, "type : ahash\n");
545 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
546 "yes" : "no");
547 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
548 seq_printf(m, "digestsize : %u\n",
549 __crypto_hash_alg_common(alg)->digestsize);
552 const struct crypto_type crypto_ahash_type = {
553 .extsize = crypto_ahash_extsize,
554 .init_tfm = crypto_ahash_init_tfm,
555 #ifdef CONFIG_PROC_FS
556 .show = crypto_ahash_show,
557 #endif
558 .report = crypto_ahash_report,
559 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
560 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
561 .type = CRYPTO_ALG_TYPE_AHASH,
562 .tfmsize = offsetof(struct crypto_ahash, base),
564 EXPORT_SYMBOL_GPL(crypto_ahash_type);
566 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
567 u32 mask)
569 return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
571 EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
573 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
575 return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
577 EXPORT_SYMBOL_GPL(crypto_has_ahash);
579 static int ahash_prepare_alg(struct ahash_alg *alg)
581 struct crypto_alg *base = &alg->halg.base;
583 if (alg->halg.digestsize > PAGE_SIZE / 8 ||
584 alg->halg.statesize > PAGE_SIZE / 8 ||
585 alg->halg.statesize == 0)
586 return -EINVAL;
588 base->cra_type = &crypto_ahash_type;
589 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
590 base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
592 return 0;
595 int crypto_register_ahash(struct ahash_alg *alg)
597 struct crypto_alg *base = &alg->halg.base;
598 int err;
600 err = ahash_prepare_alg(alg);
601 if (err)
602 return err;
604 return crypto_register_alg(base);
606 EXPORT_SYMBOL_GPL(crypto_register_ahash);
608 int crypto_unregister_ahash(struct ahash_alg *alg)
610 return crypto_unregister_alg(&alg->halg.base);
612 EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
614 int crypto_register_ahashes(struct ahash_alg *algs, int count)
616 int i, ret;
618 for (i = 0; i < count; i++) {
619 ret = crypto_register_ahash(&algs[i]);
620 if (ret)
621 goto err;
624 return 0;
626 err:
627 for (--i; i >= 0; --i)
628 crypto_unregister_ahash(&algs[i]);
630 return ret;
632 EXPORT_SYMBOL_GPL(crypto_register_ahashes);
634 void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
636 int i;
638 for (i = count - 1; i >= 0; --i)
639 crypto_unregister_ahash(&algs[i]);
641 EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);
643 int ahash_register_instance(struct crypto_template *tmpl,
644 struct ahash_instance *inst)
646 int err;
648 err = ahash_prepare_alg(&inst->alg);
649 if (err)
650 return err;
652 return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
654 EXPORT_SYMBOL_GPL(ahash_register_instance);
656 void ahash_free_instance(struct crypto_instance *inst)
658 crypto_drop_spawn(crypto_instance_ctx(inst));
659 kfree(ahash_instance(inst));
661 EXPORT_SYMBOL_GPL(ahash_free_instance);
663 int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
664 struct hash_alg_common *alg,
665 struct crypto_instance *inst)
667 return crypto_init_spawn2(&spawn->base, &alg->base, inst,
668 &crypto_ahash_type);
670 EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
672 struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
674 struct crypto_alg *alg;
676 alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
677 return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
679 EXPORT_SYMBOL_GPL(ahash_attr_alg);
681 bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
683 struct crypto_alg *alg = &halg->base;
685 if (alg->cra_type != &crypto_ahash_type)
686 return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));
688 return __crypto_ahash_alg(alg)->setkey != NULL;
690 EXPORT_SYMBOL_GPL(crypto_hash_alg_has_setkey);
692 MODULE_LICENSE("GPL");
693 MODULE_DESCRIPTION("Asynchronous cryptographic hash type");