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)
16 #include <crypto/internal/hash.h>
17 #include <crypto/scatterwalk.h>
18 #include <linux/err.h>
19 #include <linux/kernel.h>
20 #include <linux/module.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>
29 struct ahash_request_priv {
30 crypto_completion_t complete;
33 void *ubuf[] CRYPTO_MINALIGN_ATTR;
36 static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash)
38 return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
42 static int hash_walk_next(struct crypto_hash_walk *walk)
44 unsigned int alignmask = walk->alignmask;
45 unsigned int offset = walk->offset;
46 unsigned int nbytes = min(walk->entrylen,
47 ((unsigned int)(PAGE_SIZE)) - offset);
49 walk->data = crypto_kmap(walk->pg, 0);
52 if (offset & alignmask) {
53 unsigned int unaligned = alignmask + 1 - (offset & alignmask);
54 if (nbytes > unaligned)
58 walk->entrylen -= nbytes;
62 static int hash_walk_new_entry(struct crypto_hash_walk *walk)
64 struct scatterlist *sg;
67 walk->offset = sg->offset;
68 walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
69 walk->offset = offset_in_page(walk->offset);
70 walk->entrylen = sg->length;
72 if (walk->entrylen > walk->total)
73 walk->entrylen = walk->total;
74 walk->total -= walk->entrylen;
76 return hash_walk_next(walk);
79 int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
81 unsigned int alignmask = walk->alignmask;
82 unsigned int nbytes = walk->entrylen;
84 walk->data -= walk->offset;
86 if (nbytes && walk->offset & alignmask && !err) {
87 walk->offset = ALIGN(walk->offset, alignmask + 1);
88 walk->data += walk->offset;
91 ((unsigned int)(PAGE_SIZE)) - walk->offset);
92 walk->entrylen -= nbytes;
97 crypto_kunmap(walk->data, 0);
98 crypto_yield(walk->flags);
106 return hash_walk_next(walk);
112 walk->sg = scatterwalk_sg_next(walk->sg);
114 return hash_walk_new_entry(walk);
116 EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
118 int crypto_hash_walk_first(struct ahash_request *req,
119 struct crypto_hash_walk *walk)
121 walk->total = req->nbytes;
126 walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
128 walk->flags = req->base.flags;
130 return hash_walk_new_entry(walk);
132 EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
134 int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
135 struct crypto_hash_walk *walk,
136 struct scatterlist *sg, unsigned int len)
143 walk->alignmask = crypto_hash_alignmask(hdesc->tfm);
145 walk->flags = hdesc->flags;
147 return hash_walk_new_entry(walk);
150 static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
153 unsigned long alignmask = crypto_ahash_alignmask(tfm);
155 u8 *buffer, *alignbuffer;
156 unsigned long absize;
158 absize = keylen + alignmask;
159 buffer = kmalloc(absize, GFP_KERNEL);
163 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
164 memcpy(alignbuffer, key, keylen);
165 ret = tfm->setkey(tfm, alignbuffer, keylen);
170 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
173 unsigned long alignmask = crypto_ahash_alignmask(tfm);
175 if ((unsigned long)key & alignmask)
176 return ahash_setkey_unaligned(tfm, key, keylen);
178 return tfm->setkey(tfm, key, keylen);
180 EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
182 static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
188 static inline unsigned int ahash_align_buffer_size(unsigned len,
191 return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
194 static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
196 struct ahash_request_priv *priv = req->priv;
198 if (err == -EINPROGRESS)
202 memcpy(priv->result, req->result,
203 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
205 /* Restore the original crypto request. */
206 req->result = priv->result;
207 req->base.complete = priv->complete;
208 req->base.data = priv->data;
211 /* Free the req->priv.priv from the ADJUSTED request. */
215 static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
217 struct ahash_request *areq = req->data;
220 * Restore the original request, see ahash_op_unaligned() for what
223 * The "struct ahash_request *req" here is in fact the "req.base"
224 * from the ADJUSTED request from ahash_op_unaligned(), thus as it
225 * is a pointer to self, it is also the ADJUSTED "req" .
228 /* First copy areq->result into areq->priv.result */
229 ahash_op_unaligned_finish(areq, err);
231 /* Complete the ORIGINAL request. */
232 areq->base.complete(&areq->base, err);
235 static int ahash_op_unaligned(struct ahash_request *req,
236 int (*op)(struct ahash_request *))
238 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
239 unsigned long alignmask = crypto_ahash_alignmask(tfm);
240 unsigned int ds = crypto_ahash_digestsize(tfm);
241 struct ahash_request_priv *priv;
244 priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
245 (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
246 GFP_KERNEL : GFP_ATOMIC);
251 * WARNING: Voodoo programming below!
253 * The code below is obscure and hard to understand, thus explanation
254 * is necessary. See include/crypto/hash.h and include/linux/crypto.h
255 * to understand the layout of structures used here!
257 * The code here will replace portions of the ORIGINAL request with
258 * pointers to new code and buffers so the hashing operation can store
259 * the result in aligned buffer. We will call the modified request
260 * an ADJUSTED request.
262 * The newly mangled request will look as such:
265 * .result = ADJUSTED[new aligned buffer]
266 * .base.complete = ADJUSTED[pointer to completion function]
267 * .base.data = ADJUSTED[*req (pointer to self)]
268 * .priv = ADJUSTED[new priv] {
269 * .result = ORIGINAL(result)
270 * .complete = ORIGINAL(base.complete)
271 * .data = ORIGINAL(base.data)
275 priv->result = req->result;
276 priv->complete = req->base.complete;
277 priv->data = req->base.data;
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 = ahash_op_unaligned_done;
286 req->base.data = req;
290 ahash_op_unaligned_finish(req, err);
295 static int crypto_ahash_op(struct ahash_request *req,
296 int (*op)(struct ahash_request *))
298 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
299 unsigned long alignmask = crypto_ahash_alignmask(tfm);
301 if ((unsigned long)req->result & alignmask)
302 return ahash_op_unaligned(req, op);
307 int crypto_ahash_final(struct ahash_request *req)
309 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
311 EXPORT_SYMBOL_GPL(crypto_ahash_final);
313 int crypto_ahash_finup(struct ahash_request *req)
315 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
317 EXPORT_SYMBOL_GPL(crypto_ahash_finup);
319 int crypto_ahash_digest(struct ahash_request *req)
321 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
323 EXPORT_SYMBOL_GPL(crypto_ahash_digest);
325 static void ahash_def_finup_finish2(struct ahash_request *req, int err)
327 struct ahash_request_priv *priv = req->priv;
329 if (err == -EINPROGRESS)
333 memcpy(priv->result, req->result,
334 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
339 static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
341 struct ahash_request *areq = req->data;
342 struct ahash_request_priv *priv = areq->priv;
343 crypto_completion_t complete = priv->complete;
344 void *data = priv->data;
346 ahash_def_finup_finish2(areq, err);
351 static int ahash_def_finup_finish1(struct ahash_request *req, int err)
356 req->base.complete = ahash_def_finup_done2;
357 req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
358 err = crypto_ahash_reqtfm(req)->final(req);
361 ahash_def_finup_finish2(req, err);
365 static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
367 struct ahash_request *areq = req->data;
368 struct ahash_request_priv *priv = areq->priv;
369 crypto_completion_t complete = priv->complete;
370 void *data = priv->data;
372 err = ahash_def_finup_finish1(areq, err);
377 static int ahash_def_finup(struct ahash_request *req)
379 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
380 unsigned long alignmask = crypto_ahash_alignmask(tfm);
381 unsigned int ds = crypto_ahash_digestsize(tfm);
382 struct ahash_request_priv *priv;
384 priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
385 (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
386 GFP_KERNEL : GFP_ATOMIC);
390 priv->result = req->result;
391 priv->complete = req->base.complete;
392 priv->data = req->base.data;
394 req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
395 req->base.complete = ahash_def_finup_done1;
396 req->base.data = req;
399 return ahash_def_finup_finish1(req, tfm->update(req));
402 static int ahash_no_export(struct ahash_request *req, void *out)
407 static int ahash_no_import(struct ahash_request *req, const void *in)
412 static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
414 struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
415 struct ahash_alg *alg = crypto_ahash_alg(hash);
417 hash->setkey = ahash_nosetkey;
418 hash->has_setkey = false;
419 hash->export = ahash_no_export;
420 hash->import = ahash_no_import;
422 if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
423 return crypto_init_shash_ops_async(tfm);
425 hash->init = alg->init;
426 hash->update = alg->update;
427 hash->final = alg->final;
428 hash->finup = alg->finup ?: ahash_def_finup;
429 hash->digest = alg->digest;
432 hash->setkey = alg->setkey;
433 hash->has_setkey = true;
436 hash->export = alg->export;
438 hash->import = alg->import;
443 static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
445 if (alg->cra_type == &crypto_ahash_type)
446 return alg->cra_ctxsize;
448 return sizeof(struct crypto_shash *);
452 static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
454 struct crypto_report_hash rhash;
456 strncpy(rhash.type, "ahash", sizeof(rhash.type));
458 rhash.blocksize = alg->cra_blocksize;
459 rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
461 NLA_PUT(skb, CRYPTOCFGA_REPORT_HASH,
462 sizeof(struct crypto_report_hash), &rhash);
470 static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
476 static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
477 __attribute__ ((unused));
478 static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
480 seq_printf(m, "type : ahash\n");
481 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
483 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
484 seq_printf(m, "digestsize : %u\n",
485 __crypto_hash_alg_common(alg)->digestsize);
488 const struct crypto_type crypto_ahash_type = {
489 .extsize = crypto_ahash_extsize,
490 .init_tfm = crypto_ahash_init_tfm,
491 #ifdef CONFIG_PROC_FS
492 .show = crypto_ahash_show,
494 .report = crypto_ahash_report,
495 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
496 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
497 .type = CRYPTO_ALG_TYPE_AHASH,
498 .tfmsize = offsetof(struct crypto_ahash, base),
500 EXPORT_SYMBOL_GPL(crypto_ahash_type);
502 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
505 return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
507 EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
509 static int ahash_prepare_alg(struct ahash_alg *alg)
511 struct crypto_alg *base = &alg->halg.base;
513 if (alg->halg.digestsize > PAGE_SIZE / 8 ||
514 alg->halg.statesize > PAGE_SIZE / 8 ||
515 alg->halg.statesize == 0)
518 base->cra_type = &crypto_ahash_type;
519 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
520 base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
525 int crypto_register_ahash(struct ahash_alg *alg)
527 struct crypto_alg *base = &alg->halg.base;
530 err = ahash_prepare_alg(alg);
534 return crypto_register_alg(base);
536 EXPORT_SYMBOL_GPL(crypto_register_ahash);
538 int crypto_unregister_ahash(struct ahash_alg *alg)
540 return crypto_unregister_alg(&alg->halg.base);
542 EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
544 int ahash_register_instance(struct crypto_template *tmpl,
545 struct ahash_instance *inst)
549 err = ahash_prepare_alg(&inst->alg);
553 return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
555 EXPORT_SYMBOL_GPL(ahash_register_instance);
557 void ahash_free_instance(struct crypto_instance *inst)
559 crypto_drop_spawn(crypto_instance_ctx(inst));
560 kfree(ahash_instance(inst));
562 EXPORT_SYMBOL_GPL(ahash_free_instance);
564 int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
565 struct hash_alg_common *alg,
566 struct crypto_instance *inst)
568 return crypto_init_spawn2(&spawn->base, &alg->base, inst,
571 EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
573 struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
575 struct crypto_alg *alg;
577 alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
578 return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
580 EXPORT_SYMBOL_GPL(ahash_attr_alg);
582 MODULE_LICENSE("GPL");
583 MODULE_DESCRIPTION("Asynchronous cryptographic hash type");