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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Symmetric key cipher operations.
   4 *
   5 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
   6 * multiple page boundaries by using temporary blocks.  In user context,
   7 * the kernel is given a chance to schedule us once per page.
   8 *
   9 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
  10 */
  11
  12#include <crypto/internal/aead.h>
  13#include <crypto/internal/cipher.h>
  14#include <crypto/internal/skcipher.h>
  15#include <crypto/scatterwalk.h>
  16#include <linux/bug.h>
  17#include <linux/cryptouser.h>
  18#include <linux/err.h>
  19#include <linux/kernel.h>
  20#include <linux/list.h>
  21#include <linux/mm.h>
  22#include <linux/module.h>
 
  23#include <linux/seq_file.h>
  24#include <linux/slab.h>
  25#include <linux/string.h>
  26#include <net/netlink.h>
  27#include "skcipher.h"
  28
  29#define CRYPTO_ALG_TYPE_SKCIPHER_MASK	0x0000000e
  30
  31enum {
  32	SKCIPHER_WALK_PHYS = 1 << 0,
  33	SKCIPHER_WALK_SLOW = 1 << 1,
  34	SKCIPHER_WALK_COPY = 1 << 2,
  35	SKCIPHER_WALK_DIFF = 1 << 3,
  36	SKCIPHER_WALK_SLEEP = 1 << 4,
  37};
  38
  39struct skcipher_walk_buffer {
  40	struct list_head entry;
  41	struct scatter_walk dst;
  42	unsigned int len;
  43	u8 *data;
  44	u8 buffer[];
  45};
  46
  47static const struct crypto_type crypto_skcipher_type;
  48
  49static int skcipher_walk_next(struct skcipher_walk *walk);
  50
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  51static inline void skcipher_map_src(struct skcipher_walk *walk)
  52{
  53	walk->src.virt.addr = scatterwalk_map(&walk->in);
  54}
  55
  56static inline void skcipher_map_dst(struct skcipher_walk *walk)
  57{
  58	walk->dst.virt.addr = scatterwalk_map(&walk->out);
  59}
  60
  61static inline void skcipher_unmap_src(struct skcipher_walk *walk)
  62{
  63	scatterwalk_unmap(walk->src.virt.addr);
  64}
  65
  66static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
  67{
  68	scatterwalk_unmap(walk->dst.virt.addr);
  69}
  70
  71static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
  72{
  73	return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
  74}
  75
  76/* Get a spot of the specified length that does not straddle a page.
  77 * The caller needs to ensure that there is enough space for this operation.
  78 */
  79static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
  80{
  81	u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
  82
  83	return max(start, end_page);
  84}
  85
  86static inline struct skcipher_alg *__crypto_skcipher_alg(
  87	struct crypto_alg *alg)
  88{
  89	return container_of(alg, struct skcipher_alg, base);
  90}
  91
  92static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
  93{
  94	u8 *addr;
  95
  96	addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
  97	addr = skcipher_get_spot(addr, bsize);
  98	scatterwalk_copychunks(addr, &walk->out, bsize,
  99			       (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
 100	return 0;
 101}
 102
 103int skcipher_walk_done(struct skcipher_walk *walk, int err)
 104{
 105	unsigned int n = walk->nbytes;
 106	unsigned int nbytes = 0;
 107
 108	if (!n)
 109		goto finish;
 110
 111	if (likely(err >= 0)) {
 112		n -= err;
 113		nbytes = walk->total - n;
 114	}
 115
 116	if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
 117				    SKCIPHER_WALK_SLOW |
 118				    SKCIPHER_WALK_COPY |
 119				    SKCIPHER_WALK_DIFF)))) {
 120unmap_src:
 121		skcipher_unmap_src(walk);
 122	} else if (walk->flags & SKCIPHER_WALK_DIFF) {
 123		skcipher_unmap_dst(walk);
 124		goto unmap_src;
 125	} else if (walk->flags & SKCIPHER_WALK_COPY) {
 126		skcipher_map_dst(walk);
 127		memcpy(walk->dst.virt.addr, walk->page, n);
 128		skcipher_unmap_dst(walk);
 129	} else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
 130		if (err > 0) {
 131			/*
 132			 * Didn't process all bytes.  Either the algorithm is
 133			 * broken, or this was the last step and it turned out
 134			 * the message wasn't evenly divisible into blocks but
 135			 * the algorithm requires it.
 136			 */
 137			err = -EINVAL;
 138			nbytes = 0;
 139		} else
 140			n = skcipher_done_slow(walk, n);
 141	}
 142
 143	if (err > 0)
 144		err = 0;
 145
 146	walk->total = nbytes;
 147	walk->nbytes = 0;
 148
 149	scatterwalk_advance(&walk->in, n);
 150	scatterwalk_advance(&walk->out, n);
 151	scatterwalk_done(&walk->in, 0, nbytes);
 152	scatterwalk_done(&walk->out, 1, nbytes);
 153
 154	if (nbytes) {
 155		crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
 156			     CRYPTO_TFM_REQ_MAY_SLEEP : 0);
 157		return skcipher_walk_next(walk);
 158	}
 159
 160finish:
 161	/* Short-circuit for the common/fast path. */
 162	if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
 163		goto out;
 164
 165	if (walk->flags & SKCIPHER_WALK_PHYS)
 166		goto out;
 167
 168	if (walk->iv != walk->oiv)
 169		memcpy(walk->oiv, walk->iv, walk->ivsize);
 170	if (walk->buffer != walk->page)
 171		kfree(walk->buffer);
 172	if (walk->page)
 173		free_page((unsigned long)walk->page);
 174
 175out:
 176	return err;
 177}
 178EXPORT_SYMBOL_GPL(skcipher_walk_done);
 179
 180void skcipher_walk_complete(struct skcipher_walk *walk, int err)
 181{
 182	struct skcipher_walk_buffer *p, *tmp;
 183
 184	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
 185		u8 *data;
 186
 187		if (err)
 188			goto done;
 189
 190		data = p->data;
 191		if (!data) {
 192			data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
 193			data = skcipher_get_spot(data, walk->stride);
 194		}
 195
 196		scatterwalk_copychunks(data, &p->dst, p->len, 1);
 197
 198		if (offset_in_page(p->data) + p->len + walk->stride >
 199		    PAGE_SIZE)
 200			free_page((unsigned long)p->data);
 201
 202done:
 203		list_del(&p->entry);
 204		kfree(p);
 205	}
 206
 207	if (!err && walk->iv != walk->oiv)
 208		memcpy(walk->oiv, walk->iv, walk->ivsize);
 209	if (walk->buffer != walk->page)
 210		kfree(walk->buffer);
 211	if (walk->page)
 212		free_page((unsigned long)walk->page);
 213}
 214EXPORT_SYMBOL_GPL(skcipher_walk_complete);
 215
 216static void skcipher_queue_write(struct skcipher_walk *walk,
 217				 struct skcipher_walk_buffer *p)
 218{
 219	p->dst = walk->out;
 220	list_add_tail(&p->entry, &walk->buffers);
 221}
 222
 223static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
 224{
 225	bool phys = walk->flags & SKCIPHER_WALK_PHYS;
 226	unsigned alignmask = walk->alignmask;
 227	struct skcipher_walk_buffer *p;
 228	unsigned a;
 229	unsigned n;
 230	u8 *buffer;
 231	void *v;
 232
 233	if (!phys) {
 234		if (!walk->buffer)
 235			walk->buffer = walk->page;
 236		buffer = walk->buffer;
 237		if (buffer)
 238			goto ok;
 239	}
 240
 241	/* Start with the minimum alignment of kmalloc. */
 242	a = crypto_tfm_ctx_alignment() - 1;
 243	n = bsize;
 244
 245	if (phys) {
 246		/* Calculate the minimum alignment of p->buffer. */
 247		a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
 248		n += sizeof(*p);
 249	}
 250
 251	/* Minimum size to align p->buffer by alignmask. */
 252	n += alignmask & ~a;
 253
 254	/* Minimum size to ensure p->buffer does not straddle a page. */
 255	n += (bsize - 1) & ~(alignmask | a);
 256
 257	v = kzalloc(n, skcipher_walk_gfp(walk));
 258	if (!v)
 259		return skcipher_walk_done(walk, -ENOMEM);
 260
 261	if (phys) {
 262		p = v;
 263		p->len = bsize;
 264		skcipher_queue_write(walk, p);
 265		buffer = p->buffer;
 266	} else {
 267		walk->buffer = v;
 268		buffer = v;
 269	}
 270
 271ok:
 272	walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
 273	walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
 274	walk->src.virt.addr = walk->dst.virt.addr;
 275
 276	scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
 277
 278	walk->nbytes = bsize;
 279	walk->flags |= SKCIPHER_WALK_SLOW;
 280
 281	return 0;
 282}
 283
 284static int skcipher_next_copy(struct skcipher_walk *walk)
 285{
 286	struct skcipher_walk_buffer *p;
 287	u8 *tmp = walk->page;
 288
 289	skcipher_map_src(walk);
 290	memcpy(tmp, walk->src.virt.addr, walk->nbytes);
 291	skcipher_unmap_src(walk);
 292
 293	walk->src.virt.addr = tmp;
 294	walk->dst.virt.addr = tmp;
 295
 296	if (!(walk->flags & SKCIPHER_WALK_PHYS))
 297		return 0;
 298
 299	p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
 300	if (!p)
 301		return -ENOMEM;
 302
 303	p->data = walk->page;
 304	p->len = walk->nbytes;
 305	skcipher_queue_write(walk, p);
 306
 307	if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
 308	    PAGE_SIZE)
 309		walk->page = NULL;
 310	else
 311		walk->page += walk->nbytes;
 312
 313	return 0;
 314}
 315
 316static int skcipher_next_fast(struct skcipher_walk *walk)
 317{
 318	unsigned long diff;
 319
 320	walk->src.phys.page = scatterwalk_page(&walk->in);
 321	walk->src.phys.offset = offset_in_page(walk->in.offset);
 322	walk->dst.phys.page = scatterwalk_page(&walk->out);
 323	walk->dst.phys.offset = offset_in_page(walk->out.offset);
 324
 325	if (walk->flags & SKCIPHER_WALK_PHYS)
 326		return 0;
 327
 328	diff = walk->src.phys.offset - walk->dst.phys.offset;
 329	diff |= walk->src.virt.page - walk->dst.virt.page;
 330
 331	skcipher_map_src(walk);
 332	walk->dst.virt.addr = walk->src.virt.addr;
 333
 334	if (diff) {
 335		walk->flags |= SKCIPHER_WALK_DIFF;
 336		skcipher_map_dst(walk);
 337	}
 338
 339	return 0;
 340}
 341
 342static int skcipher_walk_next(struct skcipher_walk *walk)
 343{
 344	unsigned int bsize;
 345	unsigned int n;
 346	int err;
 347
 348	walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
 349			 SKCIPHER_WALK_DIFF);
 350
 351	n = walk->total;
 352	bsize = min(walk->stride, max(n, walk->blocksize));
 353	n = scatterwalk_clamp(&walk->in, n);
 354	n = scatterwalk_clamp(&walk->out, n);
 355
 356	if (unlikely(n < bsize)) {
 357		if (unlikely(walk->total < walk->blocksize))
 358			return skcipher_walk_done(walk, -EINVAL);
 359
 360slow_path:
 361		err = skcipher_next_slow(walk, bsize);
 362		goto set_phys_lowmem;
 363	}
 364
 365	if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
 366		if (!walk->page) {
 367			gfp_t gfp = skcipher_walk_gfp(walk);
 368
 369			walk->page = (void *)__get_free_page(gfp);
 370			if (!walk->page)
 371				goto slow_path;
 372		}
 373
 374		walk->nbytes = min_t(unsigned, n,
 375				     PAGE_SIZE - offset_in_page(walk->page));
 376		walk->flags |= SKCIPHER_WALK_COPY;
 377		err = skcipher_next_copy(walk);
 378		goto set_phys_lowmem;
 379	}
 380
 381	walk->nbytes = n;
 382
 383	return skcipher_next_fast(walk);
 384
 385set_phys_lowmem:
 386	if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
 387		walk->src.phys.page = virt_to_page(walk->src.virt.addr);
 388		walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
 389		walk->src.phys.offset &= PAGE_SIZE - 1;
 390		walk->dst.phys.offset &= PAGE_SIZE - 1;
 391	}
 392	return err;
 393}
 394
 395static int skcipher_copy_iv(struct skcipher_walk *walk)
 396{
 397	unsigned a = crypto_tfm_ctx_alignment() - 1;
 398	unsigned alignmask = walk->alignmask;
 399	unsigned ivsize = walk->ivsize;
 400	unsigned bs = walk->stride;
 401	unsigned aligned_bs;
 402	unsigned size;
 403	u8 *iv;
 404
 405	aligned_bs = ALIGN(bs, alignmask + 1);
 406
 407	/* Minimum size to align buffer by alignmask. */
 408	size = alignmask & ~a;
 409
 410	if (walk->flags & SKCIPHER_WALK_PHYS)
 411		size += ivsize;
 412	else {
 413		size += aligned_bs + ivsize;
 414
 415		/* Minimum size to ensure buffer does not straddle a page. */
 416		size += (bs - 1) & ~(alignmask | a);
 417	}
 418
 419	walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
 420	if (!walk->buffer)
 421		return -ENOMEM;
 422
 423	iv = PTR_ALIGN(walk->buffer, alignmask + 1);
 424	iv = skcipher_get_spot(iv, bs) + aligned_bs;
 425
 426	walk->iv = memcpy(iv, walk->iv, walk->ivsize);
 427	return 0;
 428}
 429
 430static int skcipher_walk_first(struct skcipher_walk *walk)
 431{
 432	if (WARN_ON_ONCE(in_hardirq()))
 433		return -EDEADLK;
 434
 435	walk->buffer = NULL;
 436	if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
 437		int err = skcipher_copy_iv(walk);
 438		if (err)
 439			return err;
 440	}
 441
 442	walk->page = NULL;
 443
 444	return skcipher_walk_next(walk);
 445}
 446
 447static int skcipher_walk_skcipher(struct skcipher_walk *walk,
 448				  struct skcipher_request *req)
 449{
 450	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 451	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 452
 453	walk->total = req->cryptlen;
 454	walk->nbytes = 0;
 455	walk->iv = req->iv;
 456	walk->oiv = req->iv;
 457
 458	if (unlikely(!walk->total))
 459		return 0;
 460
 461	scatterwalk_start(&walk->in, req->src);
 462	scatterwalk_start(&walk->out, req->dst);
 463
 464	walk->flags &= ~SKCIPHER_WALK_SLEEP;
 465	walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
 466		       SKCIPHER_WALK_SLEEP : 0;
 467
 468	walk->blocksize = crypto_skcipher_blocksize(tfm);
 
 469	walk->ivsize = crypto_skcipher_ivsize(tfm);
 470	walk->alignmask = crypto_skcipher_alignmask(tfm);
 471
 472	if (alg->co.base.cra_type != &crypto_skcipher_type)
 473		walk->stride = alg->co.chunksize;
 474	else
 475		walk->stride = alg->walksize;
 476
 477	return skcipher_walk_first(walk);
 478}
 479
 480int skcipher_walk_virt(struct skcipher_walk *walk,
 481		       struct skcipher_request *req, bool atomic)
 482{
 483	int err;
 484
 485	might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 486
 487	walk->flags &= ~SKCIPHER_WALK_PHYS;
 488
 489	err = skcipher_walk_skcipher(walk, req);
 490
 491	walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
 492
 493	return err;
 494}
 495EXPORT_SYMBOL_GPL(skcipher_walk_virt);
 496
 
 
 
 
 
 
 497int skcipher_walk_async(struct skcipher_walk *walk,
 498			struct skcipher_request *req)
 499{
 500	walk->flags |= SKCIPHER_WALK_PHYS;
 501
 502	INIT_LIST_HEAD(&walk->buffers);
 503
 504	return skcipher_walk_skcipher(walk, req);
 505}
 506EXPORT_SYMBOL_GPL(skcipher_walk_async);
 507
 508static int skcipher_walk_aead_common(struct skcipher_walk *walk,
 509				     struct aead_request *req, bool atomic)
 510{
 511	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 512	int err;
 513
 514	walk->nbytes = 0;
 515	walk->iv = req->iv;
 516	walk->oiv = req->iv;
 517
 518	if (unlikely(!walk->total))
 519		return 0;
 520
 521	walk->flags &= ~SKCIPHER_WALK_PHYS;
 522
 523	scatterwalk_start(&walk->in, req->src);
 524	scatterwalk_start(&walk->out, req->dst);
 525
 526	scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
 527	scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
 528
 529	scatterwalk_done(&walk->in, 0, walk->total);
 530	scatterwalk_done(&walk->out, 0, walk->total);
 531
 532	if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
 533		walk->flags |= SKCIPHER_WALK_SLEEP;
 534	else
 535		walk->flags &= ~SKCIPHER_WALK_SLEEP;
 536
 537	walk->blocksize = crypto_aead_blocksize(tfm);
 538	walk->stride = crypto_aead_chunksize(tfm);
 539	walk->ivsize = crypto_aead_ivsize(tfm);
 540	walk->alignmask = crypto_aead_alignmask(tfm);
 541
 542	err = skcipher_walk_first(walk);
 543
 544	if (atomic)
 545		walk->flags &= ~SKCIPHER_WALK_SLEEP;
 546
 547	return err;
 548}
 549
 
 
 
 
 
 
 
 
 
 550int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
 551			       struct aead_request *req, bool atomic)
 552{
 553	walk->total = req->cryptlen;
 554
 555	return skcipher_walk_aead_common(walk, req, atomic);
 556}
 557EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
 558
 559int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
 560			       struct aead_request *req, bool atomic)
 561{
 562	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 563
 564	walk->total = req->cryptlen - crypto_aead_authsize(tfm);
 565
 566	return skcipher_walk_aead_common(walk, req, atomic);
 567}
 568EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
 569
 
 
 
 
 
 
 
 
 
 
 
 570static void skcipher_set_needkey(struct crypto_skcipher *tfm)
 571{
 572	if (crypto_skcipher_max_keysize(tfm) != 0)
 573		crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
 574}
 575
 576static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
 577				     const u8 *key, unsigned int keylen)
 578{
 579	unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 580	struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
 581	u8 *buffer, *alignbuffer;
 582	unsigned long absize;
 583	int ret;
 584
 585	absize = keylen + alignmask;
 586	buffer = kmalloc(absize, GFP_ATOMIC);
 587	if (!buffer)
 588		return -ENOMEM;
 
 
 
 
 
 
 589
 590	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
 591	memcpy(alignbuffer, key, keylen);
 592	ret = cipher->setkey(tfm, alignbuffer, keylen);
 593	kfree_sensitive(buffer);
 594	return ret;
 595}
 596
 597int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
 598			   unsigned int keylen)
 
 
 
 599{
 600	struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
 601	unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 602	int err;
 
 
 
 
 603
 604	if (cipher->co.base.cra_type != &crypto_skcipher_type) {
 605		struct crypto_lskcipher **ctx = crypto_skcipher_ctx(tfm);
 606
 607		crypto_lskcipher_clear_flags(*ctx, CRYPTO_TFM_REQ_MASK);
 608		crypto_lskcipher_set_flags(*ctx,
 609					   crypto_skcipher_get_flags(tfm) &
 610					   CRYPTO_TFM_REQ_MASK);
 611		err = crypto_lskcipher_setkey(*ctx, key, keylen);
 612		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 613	}
 614
 615	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize)
 616		return -EINVAL;
 
 
 
 
 
 617
 618	if ((unsigned long)key & alignmask)
 619		err = skcipher_setkey_unaligned(tfm, key, keylen);
 620	else
 621		err = cipher->setkey(tfm, key, keylen);
 622
 623out:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 624	if (unlikely(err)) {
 625		skcipher_set_needkey(tfm);
 626		return err;
 627	}
 628
 629	crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 630	return 0;
 631}
 632EXPORT_SYMBOL_GPL(crypto_skcipher_setkey);
 633
 634int crypto_skcipher_encrypt(struct skcipher_request *req)
 
 635{
 636	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 637	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 
 638
 639	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 640		return -ENOKEY;
 641	if (alg->co.base.cra_type != &crypto_skcipher_type)
 642		return crypto_lskcipher_encrypt_sg(req);
 643	return alg->encrypt(req);
 
 
 644}
 645EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt);
 646
 647int crypto_skcipher_decrypt(struct skcipher_request *req)
 648{
 649	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 650	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 
 651
 652	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 653		return -ENOKEY;
 654	if (alg->co.base.cra_type != &crypto_skcipher_type)
 655		return crypto_lskcipher_decrypt_sg(req);
 656	return alg->decrypt(req);
 657}
 658EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt);
 659
 660static int crypto_lskcipher_export(struct skcipher_request *req, void *out)
 661{
 662	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 663	u8 *ivs = skcipher_request_ctx(req);
 
 664
 665	ivs = PTR_ALIGN(ivs, crypto_skcipher_alignmask(tfm) + 1);
 
 666
 667	memcpy(out, ivs + crypto_skcipher_ivsize(tfm),
 668	       crypto_skcipher_statesize(tfm));
 
 669
 670	return 0;
 671}
 672
 673static int crypto_lskcipher_import(struct skcipher_request *req, const void *in)
 674{
 675	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 676	u8 *ivs = skcipher_request_ctx(req);
 
 
 
 
 
 
 
 
 
 
 
 
 677
 678	ivs = PTR_ALIGN(ivs, crypto_skcipher_alignmask(tfm) + 1);
 
 
 
 
 
 
 
 
 
 
 
 679
 680	memcpy(ivs + crypto_skcipher_ivsize(tfm), in,
 681	       crypto_skcipher_statesize(tfm));
 682
 683	return 0;
 684}
 685
 686static int skcipher_noexport(struct skcipher_request *req, void *out)
 
 687{
 688	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 689}
 690
 691static int skcipher_noimport(struct skcipher_request *req, const void *in)
 
 692{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 693	return 0;
 694}
 695
 696int crypto_skcipher_export(struct skcipher_request *req, void *out)
 697{
 698	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 699	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 
 
 700
 701	if (alg->co.base.cra_type != &crypto_skcipher_type)
 702		return crypto_lskcipher_export(req, out);
 703	return alg->export(req, out);
 
 
 
 
 704}
 705EXPORT_SYMBOL_GPL(crypto_skcipher_export);
 706
 707int crypto_skcipher_import(struct skcipher_request *req, const void *in)
 708{
 709	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 710	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 
 
 711
 712	if (alg->co.base.cra_type != &crypto_skcipher_type)
 713		return crypto_lskcipher_import(req, in);
 714	return alg->import(req, in);
 
 
 
 
 715}
 716EXPORT_SYMBOL_GPL(crypto_skcipher_import);
 717
 718static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
 719{
 720	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 721	struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 722
 723	alg->exit(skcipher);
 724}
 725
 726static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
 727{
 728	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 729	struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 730
 731	skcipher_set_needkey(skcipher);
 
 732
 733	if (tfm->__crt_alg->cra_type != &crypto_skcipher_type) {
 734		unsigned am = crypto_skcipher_alignmask(skcipher);
 735		unsigned reqsize;
 736
 737		reqsize = am & ~(crypto_tfm_ctx_alignment() - 1);
 738		reqsize += crypto_skcipher_ivsize(skcipher);
 739		reqsize += crypto_skcipher_statesize(skcipher);
 740		crypto_skcipher_set_reqsize(skcipher, reqsize);
 741
 742		return crypto_init_lskcipher_ops_sg(tfm);
 743	}
 
 
 
 
 
 744
 745	if (alg->exit)
 746		skcipher->base.exit = crypto_skcipher_exit_tfm;
 747
 748	if (alg->init)
 749		return alg->init(skcipher);
 750
 751	return 0;
 752}
 753
 754static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
 755{
 756	if (alg->cra_type != &crypto_skcipher_type)
 757		return sizeof(struct crypto_lskcipher *);
 758
 759	return crypto_alg_extsize(alg);
 760}
 761
 762static void crypto_skcipher_free_instance(struct crypto_instance *inst)
 763{
 764	struct skcipher_instance *skcipher =
 765		container_of(inst, struct skcipher_instance, s.base);
 766
 767	skcipher->free(skcipher);
 768}
 769
 770static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
 771	__maybe_unused;
 772static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
 773{
 774	struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
 
 775
 776	seq_printf(m, "type         : skcipher\n");
 777	seq_printf(m, "async        : %s\n",
 778		   alg->cra_flags & CRYPTO_ALG_ASYNC ?  "yes" : "no");
 779	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 780	seq_printf(m, "min keysize  : %u\n", skcipher->min_keysize);
 781	seq_printf(m, "max keysize  : %u\n", skcipher->max_keysize);
 782	seq_printf(m, "ivsize       : %u\n", skcipher->ivsize);
 783	seq_printf(m, "chunksize    : %u\n", skcipher->chunksize);
 784	seq_printf(m, "walksize     : %u\n", skcipher->walksize);
 785	seq_printf(m, "statesize    : %u\n", skcipher->statesize);
 786}
 787
 788static int __maybe_unused crypto_skcipher_report(
 789	struct sk_buff *skb, struct crypto_alg *alg)
 790{
 791	struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
 792	struct crypto_report_blkcipher rblkcipher;
 
 
 793
 794	memset(&rblkcipher, 0, sizeof(rblkcipher));
 795
 796	strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
 797	strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
 798
 799	rblkcipher.blocksize = alg->cra_blocksize;
 800	rblkcipher.min_keysize = skcipher->min_keysize;
 801	rblkcipher.max_keysize = skcipher->max_keysize;
 802	rblkcipher.ivsize = skcipher->ivsize;
 803
 804	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
 805		       sizeof(rblkcipher), &rblkcipher);
 806}
 
 
 
 
 
 
 807
 808static const struct crypto_type crypto_skcipher_type = {
 809	.extsize = crypto_skcipher_extsize,
 810	.init_tfm = crypto_skcipher_init_tfm,
 811	.free = crypto_skcipher_free_instance,
 812#ifdef CONFIG_PROC_FS
 813	.show = crypto_skcipher_show,
 814#endif
 815#if IS_ENABLED(CONFIG_CRYPTO_USER)
 816	.report = crypto_skcipher_report,
 817#endif
 818	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
 819	.maskset = CRYPTO_ALG_TYPE_SKCIPHER_MASK,
 820	.type = CRYPTO_ALG_TYPE_SKCIPHER,
 821	.tfmsize = offsetof(struct crypto_skcipher, base),
 822};
 823
 824int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
 825			 struct crypto_instance *inst,
 826			 const char *name, u32 type, u32 mask)
 827{
 828	spawn->base.frontend = &crypto_skcipher_type;
 829	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
 830}
 831EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
 832
 833struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
 834					      u32 type, u32 mask)
 835{
 836	return crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask);
 837}
 838EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
 839
 840struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
 841				const char *alg_name, u32 type, u32 mask)
 842{
 843	struct crypto_skcipher *tfm;
 844
 845	/* Only sync algorithms allowed. */
 846	mask |= CRYPTO_ALG_ASYNC | CRYPTO_ALG_SKCIPHER_REQSIZE_LARGE;
 847
 848	tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask);
 849
 850	/*
 851	 * Make sure we do not allocate something that might get used with
 852	 * an on-stack request: check the request size.
 853	 */
 854	if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
 855				    MAX_SYNC_SKCIPHER_REQSIZE)) {
 856		crypto_free_skcipher(tfm);
 857		return ERR_PTR(-EINVAL);
 858	}
 859
 860	return (struct crypto_sync_skcipher *)tfm;
 861}
 862EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
 863
 864int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask)
 865{
 866	return crypto_type_has_alg(alg_name, &crypto_skcipher_type, type, mask);
 
 867}
 868EXPORT_SYMBOL_GPL(crypto_has_skcipher);
 869
 870int skcipher_prepare_alg_common(struct skcipher_alg_common *alg)
 871{
 872	struct crypto_alg *base = &alg->base;
 873
 874	if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
 875	    alg->statesize > PAGE_SIZE / 2 ||
 876	    (alg->ivsize + alg->statesize) > PAGE_SIZE / 2)
 877		return -EINVAL;
 878
 879	if (!alg->chunksize)
 880		alg->chunksize = base->cra_blocksize;
 881
 882	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 883
 884	return 0;
 885}
 886
 887static int skcipher_prepare_alg(struct skcipher_alg *alg)
 888{
 889	struct crypto_alg *base = &alg->base;
 890	int err;
 891
 892	err = skcipher_prepare_alg_common(&alg->co);
 893	if (err)
 894		return err;
 895
 896	if (alg->walksize > PAGE_SIZE / 8)
 897		return -EINVAL;
 898
 899	if (!alg->walksize)
 900		alg->walksize = alg->chunksize;
 901
 902	if (!alg->statesize) {
 903		alg->import = skcipher_noimport;
 904		alg->export = skcipher_noexport;
 905	} else if (!(alg->import && alg->export))
 906		return -EINVAL;
 907
 908	base->cra_type = &crypto_skcipher_type;
 909	base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
 910
 911	return 0;
 912}
 913
 914int crypto_register_skcipher(struct skcipher_alg *alg)
 915{
 916	struct crypto_alg *base = &alg->base;
 917	int err;
 918
 919	err = skcipher_prepare_alg(alg);
 920	if (err)
 921		return err;
 922
 923	return crypto_register_alg(base);
 924}
 925EXPORT_SYMBOL_GPL(crypto_register_skcipher);
 926
 927void crypto_unregister_skcipher(struct skcipher_alg *alg)
 928{
 929	crypto_unregister_alg(&alg->base);
 930}
 931EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
 932
 933int crypto_register_skciphers(struct skcipher_alg *algs, int count)
 934{
 935	int i, ret;
 936
 937	for (i = 0; i < count; i++) {
 938		ret = crypto_register_skcipher(&algs[i]);
 939		if (ret)
 940			goto err;
 941	}
 942
 943	return 0;
 944
 945err:
 946	for (--i; i >= 0; --i)
 947		crypto_unregister_skcipher(&algs[i]);
 948
 949	return ret;
 950}
 951EXPORT_SYMBOL_GPL(crypto_register_skciphers);
 952
 953void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
 954{
 955	int i;
 956
 957	for (i = count - 1; i >= 0; --i)
 958		crypto_unregister_skcipher(&algs[i]);
 959}
 960EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
 961
 962int skcipher_register_instance(struct crypto_template *tmpl,
 963			   struct skcipher_instance *inst)
 964{
 965	int err;
 966
 967	if (WARN_ON(!inst->free))
 968		return -EINVAL;
 969
 970	err = skcipher_prepare_alg(&inst->alg);
 971	if (err)
 972		return err;
 973
 974	return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
 975}
 976EXPORT_SYMBOL_GPL(skcipher_register_instance);
 977
 978static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key,
 979				  unsigned int keylen)
 980{
 981	struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
 
 982
 983	crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK);
 984	crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) &
 985				CRYPTO_TFM_REQ_MASK);
 986	return crypto_cipher_setkey(cipher, key, keylen);
 
 
 
 987}
 988
 989static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm)
 990{
 991	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
 992	struct crypto_cipher_spawn *spawn = skcipher_instance_ctx(inst);
 993	struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
 994	struct crypto_cipher *cipher;
 995
 996	cipher = crypto_spawn_cipher(spawn);
 997	if (IS_ERR(cipher))
 998		return PTR_ERR(cipher);
 999
1000	ctx->cipher = cipher;
1001	return 0;
1002}
1003
1004static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm)
1005{
1006	struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1007
1008	crypto_free_cipher(ctx->cipher);
1009}
1010
1011static void skcipher_free_instance_simple(struct skcipher_instance *inst)
1012{
1013	crypto_drop_cipher(skcipher_instance_ctx(inst));
1014	kfree(inst);
1015}
1016
1017/**
1018 * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode
1019 *
1020 * Allocate an skcipher_instance for a simple block cipher mode of operation,
1021 * e.g. cbc or ecb.  The instance context will have just a single crypto_spawn,
1022 * that for the underlying cipher.  The {min,max}_keysize, ivsize, blocksize,
1023 * alignmask, and priority are set from the underlying cipher but can be
1024 * overridden if needed.  The tfm context defaults to skcipher_ctx_simple, and
1025 * default ->setkey(), ->init(), and ->exit() methods are installed.
1026 *
1027 * @tmpl: the template being instantiated
1028 * @tb: the template parameters
 
 
1029 *
1030 * Return: a pointer to the new instance, or an ERR_PTR().  The caller still
1031 *	   needs to register the instance.
1032 */
1033struct skcipher_instance *skcipher_alloc_instance_simple(
1034	struct crypto_template *tmpl, struct rtattr **tb)
 
1035{
1036	u32 mask;
1037	struct skcipher_instance *inst;
1038	struct crypto_cipher_spawn *spawn;
1039	struct crypto_alg *cipher_alg;
 
 
 
1040	int err;
1041
1042	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
1043	if (err)
1044		return ERR_PTR(err);
 
 
 
 
 
 
 
 
 
 
 
1045
1046	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
1047	if (!inst)
1048		return ERR_PTR(-ENOMEM);
 
 
1049	spawn = skcipher_instance_ctx(inst);
1050
1051	err = crypto_grab_cipher(spawn, skcipher_crypto_instance(inst),
1052				 crypto_attr_alg_name(tb[1]), 0, mask);
1053	if (err)
1054		goto err_free_inst;
1055	cipher_alg = crypto_spawn_cipher_alg(spawn);
1056
1057	err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name,
1058				  cipher_alg);
1059	if (err)
1060		goto err_free_inst;
1061
 
 
 
 
 
1062	inst->free = skcipher_free_instance_simple;
1063
1064	/* Default algorithm properties, can be overridden */
1065	inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize;
1066	inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask;
1067	inst->alg.base.cra_priority = cipher_alg->cra_priority;
1068	inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
1069	inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
1070	inst->alg.ivsize = cipher_alg->cra_blocksize;
1071
1072	/* Use skcipher_ctx_simple by default, can be overridden */
1073	inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple);
1074	inst->alg.setkey = skcipher_setkey_simple;
1075	inst->alg.init = skcipher_init_tfm_simple;
1076	inst->alg.exit = skcipher_exit_tfm_simple;
1077
 
1078	return inst;
1079
1080err_free_inst:
1081	skcipher_free_instance_simple(inst);
 
 
1082	return ERR_PTR(err);
1083}
1084EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple);
1085
1086MODULE_LICENSE("GPL");
1087MODULE_DESCRIPTION("Symmetric key cipher type");
1088MODULE_IMPORT_NS("CRYPTO_INTERNAL");
v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Symmetric key cipher operations.
   4 *
   5 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
   6 * multiple page boundaries by using temporary blocks.  In user context,
   7 * the kernel is given a chance to schedule us once per page.
   8 *
   9 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
  10 */
  11
  12#include <crypto/internal/aead.h>
 
  13#include <crypto/internal/skcipher.h>
  14#include <crypto/scatterwalk.h>
  15#include <linux/bug.h>
  16#include <linux/cryptouser.h>
  17#include <linux/compiler.h>
 
  18#include <linux/list.h>
 
  19#include <linux/module.h>
  20#include <linux/rtnetlink.h>
  21#include <linux/seq_file.h>
 
 
  22#include <net/netlink.h>
 
  23
  24#include "internal.h"
  25
  26enum {
  27	SKCIPHER_WALK_PHYS = 1 << 0,
  28	SKCIPHER_WALK_SLOW = 1 << 1,
  29	SKCIPHER_WALK_COPY = 1 << 2,
  30	SKCIPHER_WALK_DIFF = 1 << 3,
  31	SKCIPHER_WALK_SLEEP = 1 << 4,
  32};
  33
  34struct skcipher_walk_buffer {
  35	struct list_head entry;
  36	struct scatter_walk dst;
  37	unsigned int len;
  38	u8 *data;
  39	u8 buffer[];
  40};
  41
 
 
  42static int skcipher_walk_next(struct skcipher_walk *walk);
  43
  44static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr)
  45{
  46	if (PageHighMem(scatterwalk_page(walk)))
  47		kunmap_atomic(vaddr);
  48}
  49
  50static inline void *skcipher_map(struct scatter_walk *walk)
  51{
  52	struct page *page = scatterwalk_page(walk);
  53
  54	return (PageHighMem(page) ? kmap_atomic(page) : page_address(page)) +
  55	       offset_in_page(walk->offset);
  56}
  57
  58static inline void skcipher_map_src(struct skcipher_walk *walk)
  59{
  60	walk->src.virt.addr = skcipher_map(&walk->in);
  61}
  62
  63static inline void skcipher_map_dst(struct skcipher_walk *walk)
  64{
  65	walk->dst.virt.addr = skcipher_map(&walk->out);
  66}
  67
  68static inline void skcipher_unmap_src(struct skcipher_walk *walk)
  69{
  70	skcipher_unmap(&walk->in, walk->src.virt.addr);
  71}
  72
  73static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
  74{
  75	skcipher_unmap(&walk->out, walk->dst.virt.addr);
  76}
  77
  78static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
  79{
  80	return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
  81}
  82
  83/* Get a spot of the specified length that does not straddle a page.
  84 * The caller needs to ensure that there is enough space for this operation.
  85 */
  86static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
  87{
  88	u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
  89
  90	return max(start, end_page);
  91}
  92
 
 
 
 
 
 
  93static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
  94{
  95	u8 *addr;
  96
  97	addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
  98	addr = skcipher_get_spot(addr, bsize);
  99	scatterwalk_copychunks(addr, &walk->out, bsize,
 100			       (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
 101	return 0;
 102}
 103
 104int skcipher_walk_done(struct skcipher_walk *walk, int err)
 105{
 106	unsigned int n = walk->nbytes;
 107	unsigned int nbytes = 0;
 108
 109	if (!n)
 110		goto finish;
 111
 112	if (likely(err >= 0)) {
 113		n -= err;
 114		nbytes = walk->total - n;
 115	}
 116
 117	if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
 118				    SKCIPHER_WALK_SLOW |
 119				    SKCIPHER_WALK_COPY |
 120				    SKCIPHER_WALK_DIFF)))) {
 121unmap_src:
 122		skcipher_unmap_src(walk);
 123	} else if (walk->flags & SKCIPHER_WALK_DIFF) {
 124		skcipher_unmap_dst(walk);
 125		goto unmap_src;
 126	} else if (walk->flags & SKCIPHER_WALK_COPY) {
 127		skcipher_map_dst(walk);
 128		memcpy(walk->dst.virt.addr, walk->page, n);
 129		skcipher_unmap_dst(walk);
 130	} else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
 131		if (err > 0) {
 132			/*
 133			 * Didn't process all bytes.  Either the algorithm is
 134			 * broken, or this was the last step and it turned out
 135			 * the message wasn't evenly divisible into blocks but
 136			 * the algorithm requires it.
 137			 */
 138			err = -EINVAL;
 139			nbytes = 0;
 140		} else
 141			n = skcipher_done_slow(walk, n);
 142	}
 143
 144	if (err > 0)
 145		err = 0;
 146
 147	walk->total = nbytes;
 148	walk->nbytes = 0;
 149
 150	scatterwalk_advance(&walk->in, n);
 151	scatterwalk_advance(&walk->out, n);
 152	scatterwalk_done(&walk->in, 0, nbytes);
 153	scatterwalk_done(&walk->out, 1, nbytes);
 154
 155	if (nbytes) {
 156		crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
 157			     CRYPTO_TFM_REQ_MAY_SLEEP : 0);
 158		return skcipher_walk_next(walk);
 159	}
 160
 161finish:
 162	/* Short-circuit for the common/fast path. */
 163	if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
 164		goto out;
 165
 166	if (walk->flags & SKCIPHER_WALK_PHYS)
 167		goto out;
 168
 169	if (walk->iv != walk->oiv)
 170		memcpy(walk->oiv, walk->iv, walk->ivsize);
 171	if (walk->buffer != walk->page)
 172		kfree(walk->buffer);
 173	if (walk->page)
 174		free_page((unsigned long)walk->page);
 175
 176out:
 177	return err;
 178}
 179EXPORT_SYMBOL_GPL(skcipher_walk_done);
 180
 181void skcipher_walk_complete(struct skcipher_walk *walk, int err)
 182{
 183	struct skcipher_walk_buffer *p, *tmp;
 184
 185	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
 186		u8 *data;
 187
 188		if (err)
 189			goto done;
 190
 191		data = p->data;
 192		if (!data) {
 193			data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
 194			data = skcipher_get_spot(data, walk->stride);
 195		}
 196
 197		scatterwalk_copychunks(data, &p->dst, p->len, 1);
 198
 199		if (offset_in_page(p->data) + p->len + walk->stride >
 200		    PAGE_SIZE)
 201			free_page((unsigned long)p->data);
 202
 203done:
 204		list_del(&p->entry);
 205		kfree(p);
 206	}
 207
 208	if (!err && walk->iv != walk->oiv)
 209		memcpy(walk->oiv, walk->iv, walk->ivsize);
 210	if (walk->buffer != walk->page)
 211		kfree(walk->buffer);
 212	if (walk->page)
 213		free_page((unsigned long)walk->page);
 214}
 215EXPORT_SYMBOL_GPL(skcipher_walk_complete);
 216
 217static void skcipher_queue_write(struct skcipher_walk *walk,
 218				 struct skcipher_walk_buffer *p)
 219{
 220	p->dst = walk->out;
 221	list_add_tail(&p->entry, &walk->buffers);
 222}
 223
 224static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
 225{
 226	bool phys = walk->flags & SKCIPHER_WALK_PHYS;
 227	unsigned alignmask = walk->alignmask;
 228	struct skcipher_walk_buffer *p;
 229	unsigned a;
 230	unsigned n;
 231	u8 *buffer;
 232	void *v;
 233
 234	if (!phys) {
 235		if (!walk->buffer)
 236			walk->buffer = walk->page;
 237		buffer = walk->buffer;
 238		if (buffer)
 239			goto ok;
 240	}
 241
 242	/* Start with the minimum alignment of kmalloc. */
 243	a = crypto_tfm_ctx_alignment() - 1;
 244	n = bsize;
 245
 246	if (phys) {
 247		/* Calculate the minimum alignment of p->buffer. */
 248		a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
 249		n += sizeof(*p);
 250	}
 251
 252	/* Minimum size to align p->buffer by alignmask. */
 253	n += alignmask & ~a;
 254
 255	/* Minimum size to ensure p->buffer does not straddle a page. */
 256	n += (bsize - 1) & ~(alignmask | a);
 257
 258	v = kzalloc(n, skcipher_walk_gfp(walk));
 259	if (!v)
 260		return skcipher_walk_done(walk, -ENOMEM);
 261
 262	if (phys) {
 263		p = v;
 264		p->len = bsize;
 265		skcipher_queue_write(walk, p);
 266		buffer = p->buffer;
 267	} else {
 268		walk->buffer = v;
 269		buffer = v;
 270	}
 271
 272ok:
 273	walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
 274	walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
 275	walk->src.virt.addr = walk->dst.virt.addr;
 276
 277	scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
 278
 279	walk->nbytes = bsize;
 280	walk->flags |= SKCIPHER_WALK_SLOW;
 281
 282	return 0;
 283}
 284
 285static int skcipher_next_copy(struct skcipher_walk *walk)
 286{
 287	struct skcipher_walk_buffer *p;
 288	u8 *tmp = walk->page;
 289
 290	skcipher_map_src(walk);
 291	memcpy(tmp, walk->src.virt.addr, walk->nbytes);
 292	skcipher_unmap_src(walk);
 293
 294	walk->src.virt.addr = tmp;
 295	walk->dst.virt.addr = tmp;
 296
 297	if (!(walk->flags & SKCIPHER_WALK_PHYS))
 298		return 0;
 299
 300	p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
 301	if (!p)
 302		return -ENOMEM;
 303
 304	p->data = walk->page;
 305	p->len = walk->nbytes;
 306	skcipher_queue_write(walk, p);
 307
 308	if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
 309	    PAGE_SIZE)
 310		walk->page = NULL;
 311	else
 312		walk->page += walk->nbytes;
 313
 314	return 0;
 315}
 316
 317static int skcipher_next_fast(struct skcipher_walk *walk)
 318{
 319	unsigned long diff;
 320
 321	walk->src.phys.page = scatterwalk_page(&walk->in);
 322	walk->src.phys.offset = offset_in_page(walk->in.offset);
 323	walk->dst.phys.page = scatterwalk_page(&walk->out);
 324	walk->dst.phys.offset = offset_in_page(walk->out.offset);
 325
 326	if (walk->flags & SKCIPHER_WALK_PHYS)
 327		return 0;
 328
 329	diff = walk->src.phys.offset - walk->dst.phys.offset;
 330	diff |= walk->src.virt.page - walk->dst.virt.page;
 331
 332	skcipher_map_src(walk);
 333	walk->dst.virt.addr = walk->src.virt.addr;
 334
 335	if (diff) {
 336		walk->flags |= SKCIPHER_WALK_DIFF;
 337		skcipher_map_dst(walk);
 338	}
 339
 340	return 0;
 341}
 342
 343static int skcipher_walk_next(struct skcipher_walk *walk)
 344{
 345	unsigned int bsize;
 346	unsigned int n;
 347	int err;
 348
 349	walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
 350			 SKCIPHER_WALK_DIFF);
 351
 352	n = walk->total;
 353	bsize = min(walk->stride, max(n, walk->blocksize));
 354	n = scatterwalk_clamp(&walk->in, n);
 355	n = scatterwalk_clamp(&walk->out, n);
 356
 357	if (unlikely(n < bsize)) {
 358		if (unlikely(walk->total < walk->blocksize))
 359			return skcipher_walk_done(walk, -EINVAL);
 360
 361slow_path:
 362		err = skcipher_next_slow(walk, bsize);
 363		goto set_phys_lowmem;
 364	}
 365
 366	if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
 367		if (!walk->page) {
 368			gfp_t gfp = skcipher_walk_gfp(walk);
 369
 370			walk->page = (void *)__get_free_page(gfp);
 371			if (!walk->page)
 372				goto slow_path;
 373		}
 374
 375		walk->nbytes = min_t(unsigned, n,
 376				     PAGE_SIZE - offset_in_page(walk->page));
 377		walk->flags |= SKCIPHER_WALK_COPY;
 378		err = skcipher_next_copy(walk);
 379		goto set_phys_lowmem;
 380	}
 381
 382	walk->nbytes = n;
 383
 384	return skcipher_next_fast(walk);
 385
 386set_phys_lowmem:
 387	if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
 388		walk->src.phys.page = virt_to_page(walk->src.virt.addr);
 389		walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
 390		walk->src.phys.offset &= PAGE_SIZE - 1;
 391		walk->dst.phys.offset &= PAGE_SIZE - 1;
 392	}
 393	return err;
 394}
 395
 396static int skcipher_copy_iv(struct skcipher_walk *walk)
 397{
 398	unsigned a = crypto_tfm_ctx_alignment() - 1;
 399	unsigned alignmask = walk->alignmask;
 400	unsigned ivsize = walk->ivsize;
 401	unsigned bs = walk->stride;
 402	unsigned aligned_bs;
 403	unsigned size;
 404	u8 *iv;
 405
 406	aligned_bs = ALIGN(bs, alignmask + 1);
 407
 408	/* Minimum size to align buffer by alignmask. */
 409	size = alignmask & ~a;
 410
 411	if (walk->flags & SKCIPHER_WALK_PHYS)
 412		size += ivsize;
 413	else {
 414		size += aligned_bs + ivsize;
 415
 416		/* Minimum size to ensure buffer does not straddle a page. */
 417		size += (bs - 1) & ~(alignmask | a);
 418	}
 419
 420	walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
 421	if (!walk->buffer)
 422		return -ENOMEM;
 423
 424	iv = PTR_ALIGN(walk->buffer, alignmask + 1);
 425	iv = skcipher_get_spot(iv, bs) + aligned_bs;
 426
 427	walk->iv = memcpy(iv, walk->iv, walk->ivsize);
 428	return 0;
 429}
 430
 431static int skcipher_walk_first(struct skcipher_walk *walk)
 432{
 433	if (WARN_ON_ONCE(in_irq()))
 434		return -EDEADLK;
 435
 436	walk->buffer = NULL;
 437	if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
 438		int err = skcipher_copy_iv(walk);
 439		if (err)
 440			return err;
 441	}
 442
 443	walk->page = NULL;
 444
 445	return skcipher_walk_next(walk);
 446}
 447
 448static int skcipher_walk_skcipher(struct skcipher_walk *walk,
 449				  struct skcipher_request *req)
 450{
 451	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 
 452
 453	walk->total = req->cryptlen;
 454	walk->nbytes = 0;
 455	walk->iv = req->iv;
 456	walk->oiv = req->iv;
 457
 458	if (unlikely(!walk->total))
 459		return 0;
 460
 461	scatterwalk_start(&walk->in, req->src);
 462	scatterwalk_start(&walk->out, req->dst);
 463
 464	walk->flags &= ~SKCIPHER_WALK_SLEEP;
 465	walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
 466		       SKCIPHER_WALK_SLEEP : 0;
 467
 468	walk->blocksize = crypto_skcipher_blocksize(tfm);
 469	walk->stride = crypto_skcipher_walksize(tfm);
 470	walk->ivsize = crypto_skcipher_ivsize(tfm);
 471	walk->alignmask = crypto_skcipher_alignmask(tfm);
 472
 
 
 
 
 
 473	return skcipher_walk_first(walk);
 474}
 475
 476int skcipher_walk_virt(struct skcipher_walk *walk,
 477		       struct skcipher_request *req, bool atomic)
 478{
 479	int err;
 480
 481	might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 482
 483	walk->flags &= ~SKCIPHER_WALK_PHYS;
 484
 485	err = skcipher_walk_skcipher(walk, req);
 486
 487	walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
 488
 489	return err;
 490}
 491EXPORT_SYMBOL_GPL(skcipher_walk_virt);
 492
 493void skcipher_walk_atomise(struct skcipher_walk *walk)
 494{
 495	walk->flags &= ~SKCIPHER_WALK_SLEEP;
 496}
 497EXPORT_SYMBOL_GPL(skcipher_walk_atomise);
 498
 499int skcipher_walk_async(struct skcipher_walk *walk,
 500			struct skcipher_request *req)
 501{
 502	walk->flags |= SKCIPHER_WALK_PHYS;
 503
 504	INIT_LIST_HEAD(&walk->buffers);
 505
 506	return skcipher_walk_skcipher(walk, req);
 507}
 508EXPORT_SYMBOL_GPL(skcipher_walk_async);
 509
 510static int skcipher_walk_aead_common(struct skcipher_walk *walk,
 511				     struct aead_request *req, bool atomic)
 512{
 513	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 514	int err;
 515
 516	walk->nbytes = 0;
 517	walk->iv = req->iv;
 518	walk->oiv = req->iv;
 519
 520	if (unlikely(!walk->total))
 521		return 0;
 522
 523	walk->flags &= ~SKCIPHER_WALK_PHYS;
 524
 525	scatterwalk_start(&walk->in, req->src);
 526	scatterwalk_start(&walk->out, req->dst);
 527
 528	scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
 529	scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
 530
 531	scatterwalk_done(&walk->in, 0, walk->total);
 532	scatterwalk_done(&walk->out, 0, walk->total);
 533
 534	if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
 535		walk->flags |= SKCIPHER_WALK_SLEEP;
 536	else
 537		walk->flags &= ~SKCIPHER_WALK_SLEEP;
 538
 539	walk->blocksize = crypto_aead_blocksize(tfm);
 540	walk->stride = crypto_aead_chunksize(tfm);
 541	walk->ivsize = crypto_aead_ivsize(tfm);
 542	walk->alignmask = crypto_aead_alignmask(tfm);
 543
 544	err = skcipher_walk_first(walk);
 545
 546	if (atomic)
 547		walk->flags &= ~SKCIPHER_WALK_SLEEP;
 548
 549	return err;
 550}
 551
 552int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req,
 553		       bool atomic)
 554{
 555	walk->total = req->cryptlen;
 556
 557	return skcipher_walk_aead_common(walk, req, atomic);
 558}
 559EXPORT_SYMBOL_GPL(skcipher_walk_aead);
 560
 561int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
 562			       struct aead_request *req, bool atomic)
 563{
 564	walk->total = req->cryptlen;
 565
 566	return skcipher_walk_aead_common(walk, req, atomic);
 567}
 568EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
 569
 570int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
 571			       struct aead_request *req, bool atomic)
 572{
 573	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 574
 575	walk->total = req->cryptlen - crypto_aead_authsize(tfm);
 576
 577	return skcipher_walk_aead_common(walk, req, atomic);
 578}
 579EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
 580
 581static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
 582{
 583	if (alg->cra_type == &crypto_blkcipher_type)
 584		return sizeof(struct crypto_blkcipher *);
 585
 586	if (alg->cra_type == &crypto_ablkcipher_type)
 587		return sizeof(struct crypto_ablkcipher *);
 588
 589	return crypto_alg_extsize(alg);
 590}
 591
 592static void skcipher_set_needkey(struct crypto_skcipher *tfm)
 593{
 594	if (tfm->keysize)
 595		crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
 596}
 597
 598static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
 599				     const u8 *key, unsigned int keylen)
 600{
 601	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
 602	struct crypto_blkcipher *blkcipher = *ctx;
 603	int err;
 
 
 604
 605	crypto_blkcipher_clear_flags(blkcipher, ~0);
 606	crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
 607					      CRYPTO_TFM_REQ_MASK);
 608	err = crypto_blkcipher_setkey(blkcipher, key, keylen);
 609	crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
 610				       CRYPTO_TFM_RES_MASK);
 611	if (unlikely(err)) {
 612		skcipher_set_needkey(tfm);
 613		return err;
 614	}
 615
 616	crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 617	return 0;
 
 
 
 618}
 619
 620static int skcipher_crypt_blkcipher(struct skcipher_request *req,
 621				    int (*crypt)(struct blkcipher_desc *,
 622						 struct scatterlist *,
 623						 struct scatterlist *,
 624						 unsigned int))
 625{
 626	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 627	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
 628	struct blkcipher_desc desc = {
 629		.tfm = *ctx,
 630		.info = req->iv,
 631		.flags = req->base.flags,
 632	};
 633
 
 
 634
 635	return crypt(&desc, req->dst, req->src, req->cryptlen);
 636}
 637
 638static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
 639{
 640	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 641	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 642	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
 643
 644	return skcipher_crypt_blkcipher(req, alg->encrypt);
 645}
 646
 647static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
 648{
 649	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 650	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 651	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
 652
 653	return skcipher_crypt_blkcipher(req, alg->decrypt);
 654}
 655
 656static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
 657{
 658	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
 659
 660	crypto_free_blkcipher(*ctx);
 661}
 662
 663static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
 664{
 665	struct crypto_alg *calg = tfm->__crt_alg;
 666	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 667	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
 668	struct crypto_blkcipher *blkcipher;
 669	struct crypto_tfm *btfm;
 670
 671	if (!crypto_mod_get(calg))
 672		return -EAGAIN;
 673
 674	btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
 675					CRYPTO_ALG_TYPE_MASK);
 676	if (IS_ERR(btfm)) {
 677		crypto_mod_put(calg);
 678		return PTR_ERR(btfm);
 679	}
 680
 681	blkcipher = __crypto_blkcipher_cast(btfm);
 682	*ctx = blkcipher;
 683	tfm->exit = crypto_exit_skcipher_ops_blkcipher;
 684
 685	skcipher->setkey = skcipher_setkey_blkcipher;
 686	skcipher->encrypt = skcipher_encrypt_blkcipher;
 687	skcipher->decrypt = skcipher_decrypt_blkcipher;
 688
 689	skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
 690	skcipher->keysize = calg->cra_blkcipher.max_keysize;
 
 
 691
 692	skcipher_set_needkey(skcipher);
 693
 694	return 0;
 695}
 696
 697static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
 698				      const u8 *key, unsigned int keylen)
 699{
 700	struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
 701	struct crypto_ablkcipher *ablkcipher = *ctx;
 702	int err;
 703
 704	crypto_ablkcipher_clear_flags(ablkcipher, ~0);
 705	crypto_ablkcipher_set_flags(ablkcipher,
 706				    crypto_skcipher_get_flags(tfm) &
 707				    CRYPTO_TFM_REQ_MASK);
 708	err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
 709	crypto_skcipher_set_flags(tfm,
 710				  crypto_ablkcipher_get_flags(ablkcipher) &
 711				  CRYPTO_TFM_RES_MASK);
 712	if (unlikely(err)) {
 713		skcipher_set_needkey(tfm);
 714		return err;
 715	}
 716
 717	crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 718	return 0;
 719}
 
 720
 721static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
 722				     int (*crypt)(struct ablkcipher_request *))
 723{
 724	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 725	struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
 726	struct ablkcipher_request *subreq = skcipher_request_ctx(req);
 727
 728	ablkcipher_request_set_tfm(subreq, *ctx);
 729	ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
 730					req->base.complete, req->base.data);
 731	ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
 732				     req->iv);
 733
 734	return crypt(subreq);
 735}
 
 736
 737static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
 738{
 739	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 740	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 741	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
 742
 743	return skcipher_crypt_ablkcipher(req, alg->encrypt);
 
 
 
 
 744}
 
 745
 746static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
 747{
 748	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 749	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 750	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
 751
 752	return skcipher_crypt_ablkcipher(req, alg->decrypt);
 753}
 754
 755static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
 756{
 757	struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
 758
 759	crypto_free_ablkcipher(*ctx);
 760}
 761
 762static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
 763{
 764	struct crypto_alg *calg = tfm->__crt_alg;
 765	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 766	struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
 767	struct crypto_ablkcipher *ablkcipher;
 768	struct crypto_tfm *abtfm;
 769
 770	if (!crypto_mod_get(calg))
 771		return -EAGAIN;
 772
 773	abtfm = __crypto_alloc_tfm(calg, 0, 0);
 774	if (IS_ERR(abtfm)) {
 775		crypto_mod_put(calg);
 776		return PTR_ERR(abtfm);
 777	}
 778
 779	ablkcipher = __crypto_ablkcipher_cast(abtfm);
 780	*ctx = ablkcipher;
 781	tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
 782
 783	skcipher->setkey = skcipher_setkey_ablkcipher;
 784	skcipher->encrypt = skcipher_encrypt_ablkcipher;
 785	skcipher->decrypt = skcipher_decrypt_ablkcipher;
 786
 787	skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
 788	skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
 789			    sizeof(struct ablkcipher_request);
 790	skcipher->keysize = calg->cra_ablkcipher.max_keysize;
 791
 792	skcipher_set_needkey(skcipher);
 
 793
 794	return 0;
 795}
 796
 797static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
 798				     const u8 *key, unsigned int keylen)
 799{
 800	unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 801	struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
 802	u8 *buffer, *alignbuffer;
 803	unsigned long absize;
 804	int ret;
 805
 806	absize = keylen + alignmask;
 807	buffer = kmalloc(absize, GFP_ATOMIC);
 808	if (!buffer)
 809		return -ENOMEM;
 810
 811	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
 812	memcpy(alignbuffer, key, keylen);
 813	ret = cipher->setkey(tfm, alignbuffer, keylen);
 814	kzfree(buffer);
 815	return ret;
 816}
 817
 818static int skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
 819			   unsigned int keylen)
 820{
 821	struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
 822	unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 823	int err;
 824
 825	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
 826		crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 827		return -EINVAL;
 828	}
 829
 830	if ((unsigned long)key & alignmask)
 831		err = skcipher_setkey_unaligned(tfm, key, keylen);
 832	else
 833		err = cipher->setkey(tfm, key, keylen);
 834
 835	if (unlikely(err)) {
 836		skcipher_set_needkey(tfm);
 837		return err;
 838	}
 839
 840	crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 841	return 0;
 842}
 843
 844int crypto_skcipher_encrypt(struct skcipher_request *req)
 845{
 846	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 847	struct crypto_alg *alg = tfm->base.__crt_alg;
 848	unsigned int cryptlen = req->cryptlen;
 849	int ret;
 850
 851	crypto_stats_get(alg);
 852	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 853		ret = -ENOKEY;
 854	else
 855		ret = tfm->encrypt(req);
 856	crypto_stats_skcipher_encrypt(cryptlen, ret, alg);
 857	return ret;
 858}
 859EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt);
 860
 861int crypto_skcipher_decrypt(struct skcipher_request *req)
 862{
 863	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 864	struct crypto_alg *alg = tfm->base.__crt_alg;
 865	unsigned int cryptlen = req->cryptlen;
 866	int ret;
 867
 868	crypto_stats_get(alg);
 869	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 870		ret = -ENOKEY;
 871	else
 872		ret = tfm->decrypt(req);
 873	crypto_stats_skcipher_decrypt(cryptlen, ret, alg);
 874	return ret;
 875}
 876EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt);
 877
 878static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
 879{
 880	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 881	struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 882
 883	alg->exit(skcipher);
 884}
 885
 886static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
 887{
 888	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 889	struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 890
 891	if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
 892		return crypto_init_skcipher_ops_blkcipher(tfm);
 893
 894	if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type)
 895		return crypto_init_skcipher_ops_ablkcipher(tfm);
 
 
 
 
 
 
 896
 897	skcipher->setkey = skcipher_setkey;
 898	skcipher->encrypt = alg->encrypt;
 899	skcipher->decrypt = alg->decrypt;
 900	skcipher->ivsize = alg->ivsize;
 901	skcipher->keysize = alg->max_keysize;
 902
 903	skcipher_set_needkey(skcipher);
 904
 905	if (alg->exit)
 906		skcipher->base.exit = crypto_skcipher_exit_tfm;
 907
 908	if (alg->init)
 909		return alg->init(skcipher);
 910
 911	return 0;
 912}
 913
 
 
 
 
 
 
 
 
 914static void crypto_skcipher_free_instance(struct crypto_instance *inst)
 915{
 916	struct skcipher_instance *skcipher =
 917		container_of(inst, struct skcipher_instance, s.base);
 918
 919	skcipher->free(skcipher);
 920}
 921
 922static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
 923	__maybe_unused;
 924static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
 925{
 926	struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
 927						     base);
 928
 929	seq_printf(m, "type         : skcipher\n");
 930	seq_printf(m, "async        : %s\n",
 931		   alg->cra_flags & CRYPTO_ALG_ASYNC ?  "yes" : "no");
 932	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 933	seq_printf(m, "min keysize  : %u\n", skcipher->min_keysize);
 934	seq_printf(m, "max keysize  : %u\n", skcipher->max_keysize);
 935	seq_printf(m, "ivsize       : %u\n", skcipher->ivsize);
 936	seq_printf(m, "chunksize    : %u\n", skcipher->chunksize);
 937	seq_printf(m, "walksize     : %u\n", skcipher->walksize);
 
 938}
 939
 940#ifdef CONFIG_NET
 941static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 942{
 
 943	struct crypto_report_blkcipher rblkcipher;
 944	struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
 945						     base);
 946
 947	memset(&rblkcipher, 0, sizeof(rblkcipher));
 948
 949	strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
 950	strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
 951
 952	rblkcipher.blocksize = alg->cra_blocksize;
 953	rblkcipher.min_keysize = skcipher->min_keysize;
 954	rblkcipher.max_keysize = skcipher->max_keysize;
 955	rblkcipher.ivsize = skcipher->ivsize;
 956
 957	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
 958		       sizeof(rblkcipher), &rblkcipher);
 959}
 960#else
 961static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 962{
 963	return -ENOSYS;
 964}
 965#endif
 966
 967static const struct crypto_type crypto_skcipher_type2 = {
 968	.extsize = crypto_skcipher_extsize,
 969	.init_tfm = crypto_skcipher_init_tfm,
 970	.free = crypto_skcipher_free_instance,
 971#ifdef CONFIG_PROC_FS
 972	.show = crypto_skcipher_show,
 973#endif
 
 974	.report = crypto_skcipher_report,
 
 975	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
 976	.maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
 977	.type = CRYPTO_ALG_TYPE_SKCIPHER,
 978	.tfmsize = offsetof(struct crypto_skcipher, base),
 979};
 980
 981int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
 982			  const char *name, u32 type, u32 mask)
 
 983{
 984	spawn->base.frontend = &crypto_skcipher_type2;
 985	return crypto_grab_spawn(&spawn->base, name, type, mask);
 986}
 987EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
 988
 989struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
 990					      u32 type, u32 mask)
 991{
 992	return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
 993}
 994EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
 995
 996struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
 997				const char *alg_name, u32 type, u32 mask)
 998{
 999	struct crypto_skcipher *tfm;
1000
1001	/* Only sync algorithms allowed. */
1002	mask |= CRYPTO_ALG_ASYNC;
1003
1004	tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
1005
1006	/*
1007	 * Make sure we do not allocate something that might get used with
1008	 * an on-stack request: check the request size.
1009	 */
1010	if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
1011				    MAX_SYNC_SKCIPHER_REQSIZE)) {
1012		crypto_free_skcipher(tfm);
1013		return ERR_PTR(-EINVAL);
1014	}
1015
1016	return (struct crypto_sync_skcipher *)tfm;
1017}
1018EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
1019
1020int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
1021{
1022	return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
1023				   type, mask);
1024}
1025EXPORT_SYMBOL_GPL(crypto_has_skcipher2);
1026
1027static int skcipher_prepare_alg(struct skcipher_alg *alg)
1028{
1029	struct crypto_alg *base = &alg->base;
1030
1031	if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
1032	    alg->walksize > PAGE_SIZE / 8)
 
1033		return -EINVAL;
1034
1035	if (!alg->chunksize)
1036		alg->chunksize = base->cra_blocksize;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1037	if (!alg->walksize)
1038		alg->walksize = alg->chunksize;
1039
1040	base->cra_type = &crypto_skcipher_type2;
1041	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 
 
 
 
 
1042	base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
1043
1044	return 0;
1045}
1046
1047int crypto_register_skcipher(struct skcipher_alg *alg)
1048{
1049	struct crypto_alg *base = &alg->base;
1050	int err;
1051
1052	err = skcipher_prepare_alg(alg);
1053	if (err)
1054		return err;
1055
1056	return crypto_register_alg(base);
1057}
1058EXPORT_SYMBOL_GPL(crypto_register_skcipher);
1059
1060void crypto_unregister_skcipher(struct skcipher_alg *alg)
1061{
1062	crypto_unregister_alg(&alg->base);
1063}
1064EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
1065
1066int crypto_register_skciphers(struct skcipher_alg *algs, int count)
1067{
1068	int i, ret;
1069
1070	for (i = 0; i < count; i++) {
1071		ret = crypto_register_skcipher(&algs[i]);
1072		if (ret)
1073			goto err;
1074	}
1075
1076	return 0;
1077
1078err:
1079	for (--i; i >= 0; --i)
1080		crypto_unregister_skcipher(&algs[i]);
1081
1082	return ret;
1083}
1084EXPORT_SYMBOL_GPL(crypto_register_skciphers);
1085
1086void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
1087{
1088	int i;
1089
1090	for (i = count - 1; i >= 0; --i)
1091		crypto_unregister_skcipher(&algs[i]);
1092}
1093EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
1094
1095int skcipher_register_instance(struct crypto_template *tmpl,
1096			   struct skcipher_instance *inst)
1097{
1098	int err;
1099
 
 
 
1100	err = skcipher_prepare_alg(&inst->alg);
1101	if (err)
1102		return err;
1103
1104	return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
1105}
1106EXPORT_SYMBOL_GPL(skcipher_register_instance);
1107
1108static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key,
1109				  unsigned int keylen)
1110{
1111	struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
1112	int err;
1113
1114	crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK);
1115	crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) &
1116				CRYPTO_TFM_REQ_MASK);
1117	err = crypto_cipher_setkey(cipher, key, keylen);
1118	crypto_skcipher_set_flags(tfm, crypto_cipher_get_flags(cipher) &
1119				  CRYPTO_TFM_RES_MASK);
1120	return err;
1121}
1122
1123static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm)
1124{
1125	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
1126	struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
1127	struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1128	struct crypto_cipher *cipher;
1129
1130	cipher = crypto_spawn_cipher(spawn);
1131	if (IS_ERR(cipher))
1132		return PTR_ERR(cipher);
1133
1134	ctx->cipher = cipher;
1135	return 0;
1136}
1137
1138static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm)
1139{
1140	struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1141
1142	crypto_free_cipher(ctx->cipher);
1143}
1144
1145static void skcipher_free_instance_simple(struct skcipher_instance *inst)
1146{
1147	crypto_drop_spawn(skcipher_instance_ctx(inst));
1148	kfree(inst);
1149}
1150
1151/**
1152 * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode
1153 *
1154 * Allocate an skcipher_instance for a simple block cipher mode of operation,
1155 * e.g. cbc or ecb.  The instance context will have just a single crypto_spawn,
1156 * that for the underlying cipher.  The {min,max}_keysize, ivsize, blocksize,
1157 * alignmask, and priority are set from the underlying cipher but can be
1158 * overridden if needed.  The tfm context defaults to skcipher_ctx_simple, and
1159 * default ->setkey(), ->init(), and ->exit() methods are installed.
1160 *
1161 * @tmpl: the template being instantiated
1162 * @tb: the template parameters
1163 * @cipher_alg_ret: on success, a pointer to the underlying cipher algorithm is
1164 *		    returned here.  It must be dropped with crypto_mod_put().
1165 *
1166 * Return: a pointer to the new instance, or an ERR_PTR().  The caller still
1167 *	   needs to register the instance.
1168 */
1169struct skcipher_instance *
1170skcipher_alloc_instance_simple(struct crypto_template *tmpl, struct rtattr **tb,
1171			       struct crypto_alg **cipher_alg_ret)
1172{
1173	struct crypto_attr_type *algt;
 
 
1174	struct crypto_alg *cipher_alg;
1175	struct skcipher_instance *inst;
1176	struct crypto_spawn *spawn;
1177	u32 mask;
1178	int err;
1179
1180	algt = crypto_get_attr_type(tb);
1181	if (IS_ERR(algt))
1182		return ERR_CAST(algt);
1183
1184	if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask)
1185		return ERR_PTR(-EINVAL);
1186
1187	mask = CRYPTO_ALG_TYPE_MASK |
1188		crypto_requires_off(algt->type, algt->mask,
1189				    CRYPTO_ALG_NEED_FALLBACK);
1190
1191	cipher_alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, mask);
1192	if (IS_ERR(cipher_alg))
1193		return ERR_CAST(cipher_alg);
1194
1195	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
1196	if (!inst) {
1197		err = -ENOMEM;
1198		goto err_put_cipher_alg;
1199	}
1200	spawn = skcipher_instance_ctx(inst);
1201
 
 
 
 
 
 
1202	err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name,
1203				  cipher_alg);
1204	if (err)
1205		goto err_free_inst;
1206
1207	err = crypto_init_spawn(spawn, cipher_alg,
1208				skcipher_crypto_instance(inst),
1209				CRYPTO_ALG_TYPE_MASK);
1210	if (err)
1211		goto err_free_inst;
1212	inst->free = skcipher_free_instance_simple;
1213
1214	/* Default algorithm properties, can be overridden */
1215	inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize;
1216	inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask;
1217	inst->alg.base.cra_priority = cipher_alg->cra_priority;
1218	inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
1219	inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
1220	inst->alg.ivsize = cipher_alg->cra_blocksize;
1221
1222	/* Use skcipher_ctx_simple by default, can be overridden */
1223	inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple);
1224	inst->alg.setkey = skcipher_setkey_simple;
1225	inst->alg.init = skcipher_init_tfm_simple;
1226	inst->alg.exit = skcipher_exit_tfm_simple;
1227
1228	*cipher_alg_ret = cipher_alg;
1229	return inst;
1230
1231err_free_inst:
1232	kfree(inst);
1233err_put_cipher_alg:
1234	crypto_mod_put(cipher_alg);
1235	return ERR_PTR(err);
1236}
1237EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple);
1238
1239MODULE_LICENSE("GPL");
1240MODULE_DESCRIPTION("Symmetric key cipher type");