[thirdparty/kernel/stable.git] / crypto / blkcipher.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Block chaining cipher operations.
 *
 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
 * multiple page boundaries by using temporary blocks.  In user context,
 * the kernel is given a chance to schedule us once per page.
 *
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 */

#include <crypto/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/cryptouser.h>
#include <linux/compiler.h>
#include <net/netlink.h>

#include "internal.h"

enum {
	BLKCIPHER_WALK_PHYS = 1 << 0,
	BLKCIPHER_WALK_SLOW = 1 << 1,
	BLKCIPHER_WALK_COPY = 1 << 2,
	BLKCIPHER_WALK_DIFF = 1 << 3,
};

static int blkcipher_walk_next(struct blkcipher_desc *desc,
			       struct blkcipher_walk *walk);
static int blkcipher_walk_first(struct blkcipher_desc *desc,
				struct blkcipher_walk *walk);

static inline void blkcipher_map_src(struct blkcipher_walk *walk)
{
	walk->src.virt.addr = scatterwalk_map(&walk->in);
}

static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
{
	walk->dst.virt.addr = scatterwalk_map(&walk->out);
}

static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
{
	scatterwalk_unmap(walk->src.virt.addr);
}

static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
{
	scatterwalk_unmap(walk->dst.virt.addr);
}

/* Get a spot of the specified length that does not straddle a page.
 * The caller needs to ensure that there is enough space for this operation.
 */
static inline u8 *blkcipher_get_spot(u8 *start, unsigned int len)
{
	u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
	return max(start, end_page);
}

static inline void blkcipher_done_slow(struct blkcipher_walk *walk,
				       unsigned int bsize)
{
	u8 *addr;

	addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
	addr = blkcipher_get_spot(addr, bsize);
	scatterwalk_copychunks(addr, &walk->out, bsize, 1);
}

static inline void blkcipher_done_fast(struct blkcipher_walk *walk,
				       unsigned int n)
{
	if (walk->flags & BLKCIPHER_WALK_COPY) {
		blkcipher_map_dst(walk);
		memcpy(walk->dst.virt.addr, walk->page, n);
		blkcipher_unmap_dst(walk);
	} else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
		if (walk->flags & BLKCIPHER_WALK_DIFF)
			blkcipher_unmap_dst(walk);
		blkcipher_unmap_src(walk);
	}

	scatterwalk_advance(&walk->in, n);
	scatterwalk_advance(&walk->out, n);
}

int blkcipher_walk_done(struct blkcipher_desc *desc,
			struct blkcipher_walk *walk, int err)
{
	unsigned int n; /* bytes processed */
	bool more;

	if (unlikely(err < 0))
		goto finish;

	n = walk->nbytes - err;
	walk->total -= n;
	more = (walk->total != 0);

	if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW))) {
		blkcipher_done_fast(walk, n);
	} else {
		if (WARN_ON(err)) {
			/* unexpected case; didn't process all bytes */
			err = -EINVAL;
			goto finish;
		}
		blkcipher_done_slow(walk, n);
	}

	scatterwalk_done(&walk->in, 0, more);
	scatterwalk_done(&walk->out, 1, more);

	if (more) {
		crypto_yield(desc->flags);
		return blkcipher_walk_next(desc, walk);
	}
	err = 0;
finish:
	walk->nbytes = 0;
	if (walk->iv != desc->info)
		memcpy(desc->info, walk->iv, walk->ivsize);
	if (walk->buffer != walk->page)
		kfree(walk->buffer);
	if (walk->page)
		free_page((unsigned long)walk->page);
	return err;
}
EXPORT_SYMBOL_GPL(blkcipher_walk_done);

static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
				      struct blkcipher_walk *walk,
				      unsigned int bsize,
				      unsigned int alignmask)
{
	unsigned int n;
	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);

	if (walk->buffer)
		goto ok;

	walk->buffer = walk->page;
	if (walk->buffer)
		goto ok;

	n = aligned_bsize * 3 - (alignmask + 1) +
	    (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
	walk->buffer = kmalloc(n, GFP_ATOMIC);
	if (!walk->buffer)
		return blkcipher_walk_done(desc, walk, -ENOMEM);

ok:
	walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
					  alignmask + 1);
	walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
	walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr +
						 aligned_bsize, bsize);

	scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);

	walk->nbytes = bsize;
	walk->flags |= BLKCIPHER_WALK_SLOW;

	return 0;
}

static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
{
	u8 *tmp = walk->page;

	blkcipher_map_src(walk);
	memcpy(tmp, walk->src.virt.addr, walk->nbytes);
	blkcipher_unmap_src(walk);

	walk->src.virt.addr = tmp;
	walk->dst.virt.addr = tmp;

	return 0;
}

static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
				      struct blkcipher_walk *walk)
{
	unsigned long diff;

	walk->src.phys.page = scatterwalk_page(&walk->in);
	walk->src.phys.offset = offset_in_page(walk->in.offset);
	walk->dst.phys.page = scatterwalk_page(&walk->out);
	walk->dst.phys.offset = offset_in_page(walk->out.offset);

	if (walk->flags & BLKCIPHER_WALK_PHYS)
		return 0;

	diff = walk->src.phys.offset - walk->dst.phys.offset;
	diff |= walk->src.virt.page - walk->dst.virt.page;

	blkcipher_map_src(walk);
	walk->dst.virt.addr = walk->src.virt.addr;

	if (diff) {
		walk->flags |= BLKCIPHER_WALK_DIFF;
		blkcipher_map_dst(walk);
	}

	return 0;
}

static int blkcipher_walk_next(struct blkcipher_desc *desc,
			       struct blkcipher_walk *walk)
{
	unsigned int bsize;
	unsigned int n;
	int err;

	n = walk->total;
	if (unlikely(n < walk->cipher_blocksize)) {
		desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
		return blkcipher_walk_done(desc, walk, -EINVAL);
	}

	bsize = min(walk->walk_blocksize, n);

	walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY |
			 BLKCIPHER_WALK_DIFF);
	if (!scatterwalk_aligned(&walk->in, walk->alignmask) ||
	    !scatterwalk_aligned(&walk->out, walk->alignmask)) {
		walk->flags |= BLKCIPHER_WALK_COPY;
		if (!walk->page) {
			walk->page = (void *)__get_free_page(GFP_ATOMIC);
			if (!walk->page)
				n = 0;
		}
	}

	n = scatterwalk_clamp(&walk->in, n);
	n = scatterwalk_clamp(&walk->out, n);

	if (unlikely(n < bsize)) {
		err = blkcipher_next_slow(desc, walk, bsize, walk->alignmask);
		goto set_phys_lowmem;
	}

	walk->nbytes = n;
	if (walk->flags & BLKCIPHER_WALK_COPY) {
		err = blkcipher_next_copy(walk);
		goto set_phys_lowmem;
	}

	return blkcipher_next_fast(desc, walk);

set_phys_lowmem:
	if (walk->flags & BLKCIPHER_WALK_PHYS) {
		walk->src.phys.page = virt_to_page(walk->src.virt.addr);
		walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
		walk->src.phys.offset &= PAGE_SIZE - 1;
		walk->dst.phys.offset &= PAGE_SIZE - 1;
	}
	return err;
}

static inline int blkcipher_copy_iv(struct blkcipher_walk *walk)
{
	unsigned bs = walk->walk_blocksize;
	unsigned aligned_bs = ALIGN(bs, walk->alignmask + 1);
	unsigned int size = aligned_bs * 2 +
			    walk->ivsize + max(aligned_bs, walk->ivsize) -
			    (walk->alignmask + 1);
	u8 *iv;

	size += walk->alignmask & ~(crypto_tfm_ctx_alignment() - 1);
	walk->buffer = kmalloc(size, GFP_ATOMIC);
	if (!walk->buffer)
		return -ENOMEM;

	iv = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
	iv = blkcipher_get_spot(iv, bs) + aligned_bs;
	iv = blkcipher_get_spot(iv, bs) + aligned_bs;
	iv = blkcipher_get_spot(iv, walk->ivsize);

	walk->iv = memcpy(iv, walk->iv, walk->ivsize);
	return 0;
}

int blkcipher_walk_virt(struct blkcipher_desc *desc,
			struct blkcipher_walk *walk)
{
	walk->flags &= ~BLKCIPHER_WALK_PHYS;
	walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	walk->cipher_blocksize = walk->walk_blocksize;
	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
	return blkcipher_walk_first(desc, walk);
}
EXPORT_SYMBOL_GPL(blkcipher_walk_virt);

int blkcipher_walk_phys(struct blkcipher_desc *desc,
			struct blkcipher_walk *walk)
{
	walk->flags |= BLKCIPHER_WALK_PHYS;
	walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	walk->cipher_blocksize = walk->walk_blocksize;
	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
	return blkcipher_walk_first(desc, walk);
}
EXPORT_SYMBOL_GPL(blkcipher_walk_phys);

static int blkcipher_walk_first(struct blkcipher_desc *desc,
				struct blkcipher_walk *walk)
{
	if (WARN_ON_ONCE(in_irq()))
		return -EDEADLK;

	walk->iv = desc->info;
	walk->nbytes = walk->total;
	if (unlikely(!walk->total))
		return 0;

	walk->buffer = NULL;
	if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
		int err = blkcipher_copy_iv(walk);
		if (err)
			return err;
	}

	scatterwalk_start(&walk->in, walk->in.sg);
	scatterwalk_start(&walk->out, walk->out.sg);
	walk->page = NULL;

	return blkcipher_walk_next(desc, walk);
}

int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
			      struct blkcipher_walk *walk,
			      unsigned int blocksize)
{
	walk->flags &= ~BLKCIPHER_WALK_PHYS;
	walk->walk_blocksize = blocksize;
	walk->cipher_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
	return blkcipher_walk_first(desc, walk);
}
EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block);

int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc,
				   struct blkcipher_walk *walk,
				   struct crypto_aead *tfm,
				   unsigned int blocksize)
{
	walk->flags &= ~BLKCIPHER_WALK_PHYS;
	walk->walk_blocksize = blocksize;
	walk->cipher_blocksize = crypto_aead_blocksize(tfm);
	walk->ivsize = crypto_aead_ivsize(tfm);
	walk->alignmask = crypto_aead_alignmask(tfm);
	return blkcipher_walk_first(desc, walk);
}
EXPORT_SYMBOL_GPL(blkcipher_aead_walk_virt_block);

static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
			    unsigned int keylen)
{
	struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	int ret;
	u8 *buffer, *alignbuffer;
	unsigned long absize;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_ATOMIC);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = cipher->setkey(tfm, alignbuffer, keylen);
	memset(alignbuffer, 0, keylen);
	kfree(buffer);
	return ret;
}

static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
	struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);

	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

	if ((unsigned long)key & alignmask)
		return setkey_unaligned(tfm, key, keylen);

	return cipher->setkey(tfm, key, keylen);
}

static int async_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
			unsigned int keylen)
{
	return setkey(crypto_ablkcipher_tfm(tfm), key, keylen);
}

static int async_encrypt(struct ablkcipher_request *req)
{
	struct crypto_tfm *tfm = req->base.tfm;
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	struct blkcipher_desc desc = {
		.tfm = __crypto_blkcipher_cast(tfm),
		.info = req->info,
		.flags = req->base.flags,
	};


	return alg->encrypt(&desc, req->dst, req->src, req->nbytes);
}

static int async_decrypt(struct ablkcipher_request *req)
{
	struct crypto_tfm *tfm = req->base.tfm;
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	struct blkcipher_desc desc = {
		.tfm = __crypto_blkcipher_cast(tfm),
		.info = req->info,
		.flags = req->base.flags,
	};

	return alg->decrypt(&desc, req->dst, req->src, req->nbytes);
}

static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type,
					     u32 mask)
{
	struct blkcipher_alg *cipher = &alg->cra_blkcipher;
	unsigned int len = alg->cra_ctxsize;

	if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK &&
	    cipher->ivsize) {
		len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
		len += cipher->ivsize;
	}

	return len;
}

static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm)
{
	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;

	crt->setkey = async_setkey;
	crt->encrypt = async_encrypt;
	crt->decrypt = async_decrypt;
	crt->base = __crypto_ablkcipher_cast(tfm);
	crt->ivsize = alg->ivsize;

	return 0;
}

static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm)
{
	struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
	unsigned long addr;

	crt->setkey = setkey;
	crt->encrypt = alg->encrypt;
	crt->decrypt = alg->decrypt;

	addr = (unsigned long)crypto_tfm_ctx(tfm);
	addr = ALIGN(addr, align);
	addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
	crt->iv = (void *)addr;

	return 0;
}

static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
{
	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;

	if (alg->ivsize > PAGE_SIZE / 8)
		return -EINVAL;

	if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK)
		return crypto_init_blkcipher_ops_sync(tfm);
	else
		return crypto_init_blkcipher_ops_async(tfm);
}

#ifdef CONFIG_NET
static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_blkcipher rblkcipher;

	memset(&rblkcipher, 0, sizeof(rblkcipher));

	strscpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
	strscpy(rblkcipher.geniv, "<default>", sizeof(rblkcipher.geniv));

	rblkcipher.blocksize = alg->cra_blocksize;
	rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
	rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
	rblkcipher.ivsize = alg->cra_blkcipher.ivsize;

	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
		       sizeof(rblkcipher), &rblkcipher);
}
#else
static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	return -ENOSYS;
}
#endif

static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
	__maybe_unused;
static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
	seq_printf(m, "type         : blkcipher\n");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "min keysize  : %u\n", alg->cra_blkcipher.min_keysize);
	seq_printf(m, "max keysize  : %u\n", alg->cra_blkcipher.max_keysize);
	seq_printf(m, "ivsize       : %u\n", alg->cra_blkcipher.ivsize);
	seq_printf(m, "geniv        : <default>\n");
}

const struct crypto_type crypto_blkcipher_type = {
	.ctxsize = crypto_blkcipher_ctxsize,
	.init = crypto_init_blkcipher_ops,
#ifdef CONFIG_PROC_FS
	.show = crypto_blkcipher_show,
#endif
	.report = crypto_blkcipher_report,
};
EXPORT_SYMBOL_GPL(crypto_blkcipher_type);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Generic block chaining cipher type");
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
5cde0af2 HX	2	/*
5cde0af2 HX	3	* Block chaining cipher operations.
d8c34b94	4	*
5cde0af2 HX	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) 2006 Herbert Xu <herbert@gondor.apana.org.au>
5cde0af2 HX	10	*/
5cde0af2 HX	11
d1a2fd50	12	#include <crypto/aead.h>
ecfc4329	13	#include <crypto/internal/skcipher.h>
42c271c6	14	#include <crypto/scatterwalk.h>
5cde0af2 HX	15	#include <linux/errno.h>
5cde0af2 HX	16	#include <linux/kernel.h>
5cde0af2	17	#include <linux/module.h>
5cde0af2 HX	18	#include <linux/seq_file.h>
	19	#include <linux/slab.h>
	20	#include <linux/string.h>
50496a1f	21	#include <linux/cryptouser.h>
d8c34b94	22	#include <linux/compiler.h>
50496a1f	23	#include <net/netlink.h>
5cde0af2 HX	24
5cde0af2 HX	25	#include "internal.h"
5cde0af2 HX	26
	27	enum {
	28	BLKCIPHER_WALK_PHYS = 1 << 0,
	29	BLKCIPHER_WALK_SLOW = 1 << 1,
	30	BLKCIPHER_WALK_COPY = 1 << 2,
	31	BLKCIPHER_WALK_DIFF = 1 << 3,
	32	};
	33
	34	static int blkcipher_walk_next(struct blkcipher_desc *desc,
	35	struct blkcipher_walk *walk);
	36	static int blkcipher_walk_first(struct blkcipher_desc *desc,
	37	struct blkcipher_walk *walk);
	38
	39	static inline void blkcipher_map_src(struct blkcipher_walk *walk)
	40	{
f0dfc0b0	41	walk->src.virt.addr = scatterwalk_map(&walk->in);
5cde0af2 HX	42	}
	43
	44	static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
	45	{
f0dfc0b0	46	walk->dst.virt.addr = scatterwalk_map(&walk->out);
5cde0af2 HX	47	}
	48
	49	static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
	50	{
f0dfc0b0	51	scatterwalk_unmap(walk->src.virt.addr);
5cde0af2 HX	52	}
	53
	54	static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
	55	{
f0dfc0b0	56	scatterwalk_unmap(walk->dst.virt.addr);
5cde0af2 HX	57	}
5cde0af2 HX	58
e4630f9f HX	59	/* Get a spot of the specified length that does not straddle a page.
	60	* The caller needs to ensure that there is enough space for this operation.
	61	*/
5cde0af2 HX	62	static inline u8 blkcipher_get_spot(u8 start, unsigned int len)
5cde0af2 HX	63	{
e4630f9f	64	u8 end_page = (u8 )(((unsigned long)(start + len - 1)) & PAGE_MASK);
5aaff0c8	65	return max(start, end_page);
5cde0af2 HX	66	}
5cde0af2 HX	67
0868def3 EB	68	static inline void blkcipher_done_slow(struct blkcipher_walk *walk,
0868def3 EB	69	unsigned int bsize)
5cde0af2 HX	70	{
5cde0af2 HX	71	u8 *addr;
5cde0af2	72
822be00f	73	addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
5cde0af2 HX	74	addr = blkcipher_get_spot(addr, bsize);
5cde0af2 HX	75	scatterwalk_copychunks(addr, &walk->out, bsize, 1);
5cde0af2 HX	76	}
5cde0af2 HX	77
0868def3 EB	78	static inline void blkcipher_done_fast(struct blkcipher_walk *walk,
0868def3 EB	79	unsigned int n)
5cde0af2	80	{
5cde0af2 HX	81	if (walk->flags & BLKCIPHER_WALK_COPY) {
	82	blkcipher_map_dst(walk);
	83	memcpy(walk->dst.virt.addr, walk->page, n);
	84	blkcipher_unmap_dst(walk);
	85	} else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
5cde0af2 HX	86	if (walk->flags & BLKCIPHER_WALK_DIFF)
5cde0af2 HX	87	blkcipher_unmap_dst(walk);
61ecdb80	88	blkcipher_unmap_src(walk);
5cde0af2 HX	89	}
	90
	91	scatterwalk_advance(&walk->in, n);
	92	scatterwalk_advance(&walk->out, n);
5cde0af2 HX	93	}
	94
	95	int blkcipher_walk_done(struct blkcipher_desc *desc,
	96	struct blkcipher_walk *walk, int err)
	97	{
0868def3 EB	98	unsigned int n; /* bytes processed */
0868def3 EB	99	bool more;
5cde0af2	100
0868def3 EB	101	if (unlikely(err < 0))
0868def3 EB	102	goto finish;
5cde0af2	103
0868def3 EB	104	n = walk->nbytes - err;
	105	walk->total -= n;
	106	more = (walk->total != 0);
5cde0af2	107
0868def3 EB	108	if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW))) {
	109	blkcipher_done_fast(walk, n);
	110	} else {
	111	if (WARN_ON(err)) {
	112	/* unexpected case; didn't process all bytes */
	113	err = -EINVAL;
	114	goto finish;
	115	}
	116	blkcipher_done_slow(walk, n);
5cde0af2 HX	117	}
5cde0af2 HX	118
0868def3 EB	119	scatterwalk_done(&walk->in, 0, more);
0868def3 EB	120	scatterwalk_done(&walk->out, 1, more);
5cde0af2	121
0868def3	122	if (more) {
5cde0af2 HX	123	crypto_yield(desc->flags);
	124	return blkcipher_walk_next(desc, walk);
	125	}
0868def3 EB	126	err = 0;
	127	finish:
	128	walk->nbytes = 0;
5cde0af2	129	if (walk->iv != desc->info)
822be00f	130	memcpy(desc->info, walk->iv, walk->ivsize);
5cde0af2 HX	131	if (walk->buffer != walk->page)
	132	kfree(walk->buffer);
	133	if (walk->page)
	134	free_page((unsigned long)walk->page);
5cde0af2 HX	135	return err;
	136	}
	137	EXPORT_SYMBOL_GPL(blkcipher_walk_done);
	138
	139	static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
	140	struct blkcipher_walk *walk,
	141	unsigned int bsize,
	142	unsigned int alignmask)
	143	{
	144	unsigned int n;
70613783	145	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
5cde0af2 HX	146
	147	if (walk->buffer)
	148	goto ok;
	149
	150	walk->buffer = walk->page;
	151	if (walk->buffer)
	152	goto ok;
	153
2614de1b	154	n = aligned_bsize * 3 - (alignmask + 1) +
e4630f9f	155	(alignmask & ~(crypto_tfm_ctx_alignment() - 1));
5cde0af2 HX	156	walk->buffer = kmalloc(n, GFP_ATOMIC);
	157	if (!walk->buffer)
	158	return blkcipher_walk_done(desc, walk, -ENOMEM);
	159
	160	ok:
	161	walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
	162	alignmask + 1);
	163	walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
70613783 HX	164	walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr +
70613783 HX	165	aligned_bsize, bsize);
5cde0af2 HX	166
	167	scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
	168
	169	walk->nbytes = bsize;
	170	walk->flags \|= BLKCIPHER_WALK_SLOW;
	171
	172	return 0;
	173	}
	174
	175	static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
	176	{
	177	u8 *tmp = walk->page;
	178
	179	blkcipher_map_src(walk);
	180	memcpy(tmp, walk->src.virt.addr, walk->nbytes);
	181	blkcipher_unmap_src(walk);
	182
	183	walk->src.virt.addr = tmp;
	184	walk->dst.virt.addr = tmp;
	185
	186	return 0;
	187	}
	188
	189	static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
	190	struct blkcipher_walk *walk)
	191	{
	192	unsigned long diff;
	193
	194	walk->src.phys.page = scatterwalk_page(&walk->in);
	195	walk->src.phys.offset = offset_in_page(walk->in.offset);
	196	walk->dst.phys.page = scatterwalk_page(&walk->out);
	197	walk->dst.phys.offset = offset_in_page(walk->out.offset);
	198
	199	if (walk->flags & BLKCIPHER_WALK_PHYS)
	200	return 0;
	201
	202	diff = walk->src.phys.offset - walk->dst.phys.offset;
	203	diff \|= walk->src.virt.page - walk->dst.virt.page;
	204
	205	blkcipher_map_src(walk);
	206	walk->dst.virt.addr = walk->src.virt.addr;
	207
	208	if (diff) {
	209	walk->flags \|= BLKCIPHER_WALK_DIFF;
	210	blkcipher_map_dst(walk);
	211	}
	212
	213	return 0;
	214	}
	215
	216	static int blkcipher_walk_next(struct blkcipher_desc *desc,
	217	struct blkcipher_walk *walk)
	218	{
7607bd8f	219	unsigned int bsize;
5cde0af2 HX	220	unsigned int n;
	221	int err;
	222
	223	n = walk->total;
822be00f	224	if (unlikely(n < walk->cipher_blocksize)) {
5cde0af2 HX	225	desc->flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
	226	return blkcipher_walk_done(desc, walk, -EINVAL);
	227	}
	228
acdb04d0 HX	229	bsize = min(walk->walk_blocksize, n);
acdb04d0 HX	230
5cde0af2 HX	231	walk->flags &= ~(BLKCIPHER_WALK_SLOW \| BLKCIPHER_WALK_COPY \|
5cde0af2 HX	232	BLKCIPHER_WALK_DIFF);
822be00f AB	233	if (!scatterwalk_aligned(&walk->in, walk->alignmask) \|\|
822be00f AB	234	!scatterwalk_aligned(&walk->out, walk->alignmask)) {
5cde0af2 HX	235	walk->flags \|= BLKCIPHER_WALK_COPY;
	236	if (!walk->page) {
	237	walk->page = (void *)__get_free_page(GFP_ATOMIC);
	238	if (!walk->page)
	239	n = 0;
	240	}
	241	}
	242
	243	n = scatterwalk_clamp(&walk->in, n);
	244	n = scatterwalk_clamp(&walk->out, n);
	245
	246	if (unlikely(n < bsize)) {
822be00f	247	err = blkcipher_next_slow(desc, walk, bsize, walk->alignmask);
5cde0af2 HX	248	goto set_phys_lowmem;
	249	}
	250
	251	walk->nbytes = n;
	252	if (walk->flags & BLKCIPHER_WALK_COPY) {
	253	err = blkcipher_next_copy(walk);
	254	goto set_phys_lowmem;
	255	}
	256
	257	return blkcipher_next_fast(desc, walk);
	258
	259	set_phys_lowmem:
	260	if (walk->flags & BLKCIPHER_WALK_PHYS) {
	261	walk->src.phys.page = virt_to_page(walk->src.virt.addr);
	262	walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
	263	walk->src.phys.offset &= PAGE_SIZE - 1;
	264	walk->dst.phys.offset &= PAGE_SIZE - 1;
	265	}
	266	return err;
	267	}
	268
822be00f	269	static inline int blkcipher_copy_iv(struct blkcipher_walk *walk)
5cde0af2	270	{
822be00f AB	271	unsigned bs = walk->walk_blocksize;
	272	unsigned aligned_bs = ALIGN(bs, walk->alignmask + 1);
	273	unsigned int size = aligned_bs * 2 +
	274	walk->ivsize + max(aligned_bs, walk->ivsize) -
	275	(walk->alignmask + 1);
5cde0af2 HX	276	u8 *iv;
5cde0af2 HX	277
822be00f	278	size += walk->alignmask & ~(crypto_tfm_ctx_alignment() - 1);
5cde0af2 HX	279	walk->buffer = kmalloc(size, GFP_ATOMIC);
	280	if (!walk->buffer)
	281	return -ENOMEM;
	282
822be00f	283	iv = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
70613783 HX	284	iv = blkcipher_get_spot(iv, bs) + aligned_bs;
70613783 HX	285	iv = blkcipher_get_spot(iv, bs) + aligned_bs;
822be00f	286	iv = blkcipher_get_spot(iv, walk->ivsize);
5cde0af2	287
822be00f	288	walk->iv = memcpy(iv, walk->iv, walk->ivsize);
5cde0af2 HX	289	return 0;
	290	}
	291
	292	int blkcipher_walk_virt(struct blkcipher_desc *desc,
	293	struct blkcipher_walk *walk)
	294	{
	295	walk->flags &= ~BLKCIPHER_WALK_PHYS;
822be00f AB	296	walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	297	walk->cipher_blocksize = walk->walk_blocksize;
	298	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	299	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
5cde0af2 HX	300	return blkcipher_walk_first(desc, walk);
	301	}
	302	EXPORT_SYMBOL_GPL(blkcipher_walk_virt);
	303
	304	int blkcipher_walk_phys(struct blkcipher_desc *desc,
	305	struct blkcipher_walk *walk)
	306	{
	307	walk->flags \|= BLKCIPHER_WALK_PHYS;
822be00f AB	308	walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	309	walk->cipher_blocksize = walk->walk_blocksize;
	310	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	311	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
5cde0af2 HX	312	return blkcipher_walk_first(desc, walk);
	313	}
	314	EXPORT_SYMBOL_GPL(blkcipher_walk_phys);
	315
	316	static int blkcipher_walk_first(struct blkcipher_desc *desc,
	317	struct blkcipher_walk *walk)
	318	{
fb469840 HX	319	if (WARN_ON_ONCE(in_irq()))
	320	return -EDEADLK;
	321
70d906bc	322	walk->iv = desc->info;
5cde0af2 HX	323	walk->nbytes = walk->total;
	324	if (unlikely(!walk->total))
	325	return 0;
	326
	327	walk->buffer = NULL;
822be00f AB	328	if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
822be00f AB	329	int err = blkcipher_copy_iv(walk);
5cde0af2 HX	330	if (err)
	331	return err;
	332	}
	333
	334	scatterwalk_start(&walk->in, walk->in.sg);
	335	scatterwalk_start(&walk->out, walk->out.sg);
	336	walk->page = NULL;
	337
	338	return blkcipher_walk_next(desc, walk);
	339	}
	340
7607bd8f HX	341	int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
	342	struct blkcipher_walk *walk,
	343	unsigned int blocksize)
	344	{
	345	walk->flags &= ~BLKCIPHER_WALK_PHYS;
822be00f AB	346	walk->walk_blocksize = blocksize;
	347	walk->cipher_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	348	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	349	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
7607bd8f HX	350	return blkcipher_walk_first(desc, walk);
	351	}
	352	EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block);
	353
4f7f1d7c AB	354	int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc,
	355	struct blkcipher_walk *walk,
	356	struct crypto_aead *tfm,
	357	unsigned int blocksize)
	358	{
	359	walk->flags &= ~BLKCIPHER_WALK_PHYS;
	360	walk->walk_blocksize = blocksize;
	361	walk->cipher_blocksize = crypto_aead_blocksize(tfm);
	362	walk->ivsize = crypto_aead_ivsize(tfm);
	363	walk->alignmask = crypto_aead_alignmask(tfm);
	364	return blkcipher_walk_first(desc, walk);
	365	}
	366	EXPORT_SYMBOL_GPL(blkcipher_aead_walk_virt_block);
	367
791b4d5f HX	368	static int setkey_unaligned(struct crypto_tfm tfm, const u8 key,
791b4d5f HX	369	unsigned int keylen)
ca7c3938 SS	370	{
	371	struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
	372	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	373	int ret;
	374	u8 buffer, alignbuffer;
	375	unsigned long absize;
	376
	377	absize = keylen + alignmask;
	378	buffer = kmalloc(absize, GFP_ATOMIC);
	379	if (!buffer)
	380	return -ENOMEM;
	381
	382	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	383	memcpy(alignbuffer, key, keylen);
	384	ret = cipher->setkey(tfm, alignbuffer, keylen);
06817176	385	memset(alignbuffer, 0, keylen);
ca7c3938 SS	386	kfree(buffer);
	387	return ret;
	388	}
	389
791b4d5f	390	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
5cde0af2 HX	391	{
5cde0af2 HX	392	struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
ca7c3938	393	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
5cde0af2 HX	394
	395	if (keylen < cipher->min_keysize \|\| keylen > cipher->max_keysize) {
	396	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	397	return -EINVAL;
	398	}
	399
ca7c3938 SS	400	if ((unsigned long)key & alignmask)
	401	return setkey_unaligned(tfm, key, keylen);
	402
5cde0af2 HX	403	return cipher->setkey(tfm, key, keylen);
	404	}
	405
32e3983f HX	406	static int async_setkey(struct crypto_ablkcipher tfm, const u8 key,
	407	unsigned int keylen)
	408	{
	409	return setkey(crypto_ablkcipher_tfm(tfm), key, keylen);
	410	}
	411
	412	static int async_encrypt(struct ablkcipher_request *req)
	413	{
	414	struct crypto_tfm *tfm = req->base.tfm;
	415	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	416	struct blkcipher_desc desc = {
	417	.tfm = __crypto_blkcipher_cast(tfm),
	418	.info = req->info,
	419	.flags = req->base.flags,
	420	};
	421
	422
	423	return alg->encrypt(&desc, req->dst, req->src, req->nbytes);
	424	}
	425
	426	static int async_decrypt(struct ablkcipher_request *req)
	427	{
	428	struct crypto_tfm *tfm = req->base.tfm;
	429	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	430	struct blkcipher_desc desc = {
	431	.tfm = __crypto_blkcipher_cast(tfm),
	432	.info = req->info,
	433	.flags = req->base.flags,
	434	};
	435
	436	return alg->decrypt(&desc, req->dst, req->src, req->nbytes);
	437	}
	438
27d2a330 HX	439	static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type,
27d2a330 HX	440	u32 mask)
5cde0af2 HX	441	{
	442	struct blkcipher_alg *cipher = &alg->cra_blkcipher;
	443	unsigned int len = alg->cra_ctxsize;
	444
332f8840 HX	445	if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK &&
332f8840 HX	446	cipher->ivsize) {
5cde0af2 HX	447	len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
	448	len += cipher->ivsize;
	449	}
	450
	451	return len;
	452	}
	453
32e3983f HX	454	static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm)
	455	{
	456	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	457	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	458
	459	crt->setkey = async_setkey;
	460	crt->encrypt = async_encrypt;
	461	crt->decrypt = async_decrypt;
ecfc4329	462	crt->base = __crypto_ablkcipher_cast(tfm);
32e3983f HX	463	crt->ivsize = alg->ivsize;
	464
	465	return 0;
	466	}
	467
	468	static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm)
5cde0af2 HX	469	{
	470	struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
	471	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	472	unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
	473	unsigned long addr;
	474
5cde0af2 HX	475	crt->setkey = setkey;
	476	crt->encrypt = alg->encrypt;
	477	crt->decrypt = alg->decrypt;
	478
	479	addr = (unsigned long)crypto_tfm_ctx(tfm);
	480	addr = ALIGN(addr, align);
	481	addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
	482	crt->iv = (void *)addr;
	483
	484	return 0;
	485	}
	486
32e3983f HX	487	static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
	488	{
	489	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	490
	491	if (alg->ivsize > PAGE_SIZE / 8)
	492	return -EINVAL;
	493
332f8840	494	if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK)
32e3983f HX	495	return crypto_init_blkcipher_ops_sync(tfm);
	496	else
	497	return crypto_init_blkcipher_ops_async(tfm);
	498	}
	499
3acc8473	500	#ifdef CONFIG_NET
50496a1f SK	501	static int crypto_blkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	502	{
	503	struct crypto_report_blkcipher rblkcipher;
	504
37db69e0 EB	505	memset(&rblkcipher, 0, sizeof(rblkcipher));
	506
	507	strscpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
c79b411e	508	strscpy(rblkcipher.geniv, "<default>", sizeof(rblkcipher.geniv));
50496a1f SK	509
	510	rblkcipher.blocksize = alg->cra_blocksize;
	511	rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
	512	rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
	513	rblkcipher.ivsize = alg->cra_blkcipher.ivsize;
	514
37db69e0 EB	515	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
37db69e0 EB	516	sizeof(rblkcipher), &rblkcipher);
50496a1f	517	}
3acc8473 HX	518	#else
	519	static int crypto_blkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	520	{
	521	return -ENOSYS;
	522	}
	523	#endif
50496a1f	524
5cde0af2	525	static void crypto_blkcipher_show(struct seq_file m, struct crypto_alg alg)
d8c34b94	526	__maybe_unused;
5cde0af2 HX	527	static void crypto_blkcipher_show(struct seq_file m, struct crypto_alg alg)
	528	{
	529	seq_printf(m, "type : blkcipher\n");
	530	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	531	seq_printf(m, "min keysize : %u\n", alg->cra_blkcipher.min_keysize);
	532	seq_printf(m, "max keysize : %u\n", alg->cra_blkcipher.max_keysize);
	533	seq_printf(m, "ivsize : %u\n", alg->cra_blkcipher.ivsize);
c79b411e	534	seq_printf(m, "geniv : <default>\n");
5cde0af2 HX	535	}
	536
	537	const struct crypto_type crypto_blkcipher_type = {
	538	.ctxsize = crypto_blkcipher_ctxsize,
	539	.init = crypto_init_blkcipher_ops,
	540	#ifdef CONFIG_PROC_FS
	541	.show = crypto_blkcipher_show,
	542	#endif
50496a1f	543	.report = crypto_blkcipher_report,
5cde0af2 HX	544	};
	545	EXPORT_SYMBOL_GPL(crypto_blkcipher_type);
	546
	547	MODULE_LICENSE("GPL");
	548	MODULE_DESCRIPTION("Generic block chaining cipher type");