[mirror_ubuntu-zesty-kernel.git] / crypto / blkcipher.c

/*
 * 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>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option) 
 * any later version.
 *
 */

#include <crypto/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/errno.h>
#include <linux/hardirq.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 <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 unsigned int 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);
	return bsize;
}

static inline unsigned int 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);

	return n;
}

int blkcipher_walk_done(struct blkcipher_desc *desc,
			struct blkcipher_walk *walk, int err)
{
	unsigned int nbytes = 0;

	if (likely(err >= 0)) {
		unsigned int n = walk->nbytes - err;

		if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW)))
			n = blkcipher_done_fast(walk, n);
		else if (WARN_ON(err)) {
			err = -EINVAL;
			goto err;
		} else
			n = blkcipher_done_slow(walk, n);

		nbytes = walk->total - n;
		err = 0;
	}

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

err:
	walk->total = nbytes;
	walk->nbytes = nbytes;

	if (nbytes) {
		crypto_yield(desc->flags);
		return blkcipher_walk_next(desc, walk);
	}

	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;

	strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
	strncpy(rblkcipher.geniv, alg->cra_blkcipher.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;

	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}
#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)
	__attribute__ ((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        : %s\n", alg->cra_blkcipher.geniv ?:
					     "<default>");
}

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
5cde0af2 HX	1	/*
	2	* Block chaining cipher operations.
	3	*
	4	* Generic encrypt/decrypt wrapper for ciphers, handles operations across
	5	* multiple page boundaries by using temporary blocks. In user context,
	6	* the kernel is given a chance to schedule us once per page.
	7	*
	8	* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
	9	*
	10	* This program is free software; you can redistribute it and/or modify it
	11	* under the terms of the GNU General Public License as published by the Free
	12	* Software Foundation; either version 2 of the License, or (at your option)
	13	* any later version.
	14	*
	15	*/
	16
d1a2fd50	17	#include <crypto/aead.h>
ecfc4329	18	#include <crypto/internal/skcipher.h>
42c271c6	19	#include <crypto/scatterwalk.h>
5cde0af2	20	#include <linux/errno.h>
fb469840	21	#include <linux/hardirq.h>
5cde0af2	22	#include <linux/kernel.h>
5cde0af2	23	#include <linux/module.h>
5cde0af2 HX	24	#include <linux/seq_file.h>
	25	#include <linux/slab.h>
	26	#include <linux/string.h>
50496a1f SK	27	#include <linux/cryptouser.h>
50496a1f SK	28	#include <net/netlink.h>
5cde0af2 HX	29
5cde0af2 HX	30	#include "internal.h"
5cde0af2 HX	31
	32	enum {
	33	BLKCIPHER_WALK_PHYS = 1 << 0,
	34	BLKCIPHER_WALK_SLOW = 1 << 1,
	35	BLKCIPHER_WALK_COPY = 1 << 2,
	36	BLKCIPHER_WALK_DIFF = 1 << 3,
	37	};
	38
	39	static int blkcipher_walk_next(struct blkcipher_desc *desc,
	40	struct blkcipher_walk *walk);
	41	static int blkcipher_walk_first(struct blkcipher_desc *desc,
	42	struct blkcipher_walk *walk);
	43
	44	static inline void blkcipher_map_src(struct blkcipher_walk *walk)
	45	{
f0dfc0b0	46	walk->src.virt.addr = scatterwalk_map(&walk->in);
5cde0af2 HX	47	}
	48
	49	static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
	50	{
f0dfc0b0	51	walk->dst.virt.addr = scatterwalk_map(&walk->out);
5cde0af2 HX	52	}
	53
	54	static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
	55	{
f0dfc0b0	56	scatterwalk_unmap(walk->src.virt.addr);
5cde0af2 HX	57	}
	58
	59	static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
	60	{
f0dfc0b0	61	scatterwalk_unmap(walk->dst.virt.addr);
5cde0af2 HX	62	}
5cde0af2 HX	63
e4630f9f HX	64	/* Get a spot of the specified length that does not straddle a page.
	65	* The caller needs to ensure that there is enough space for this operation.
	66	*/
5cde0af2 HX	67	static inline u8 blkcipher_get_spot(u8 start, unsigned int len)
5cde0af2 HX	68	{
e4630f9f	69	u8 end_page = (u8 )(((unsigned long)(start + len - 1)) & PAGE_MASK);
5aaff0c8	70	return max(start, end_page);
5cde0af2 HX	71	}
5cde0af2 HX	72
822be00f	73	static inline unsigned int blkcipher_done_slow(struct blkcipher_walk *walk,
5cde0af2 HX	74	unsigned int bsize)
	75	{
	76	u8 *addr;
5cde0af2	77
822be00f	78	addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
5cde0af2 HX	79	addr = blkcipher_get_spot(addr, bsize);
	80	scatterwalk_copychunks(addr, &walk->out, bsize, 1);
	81	return bsize;
	82	}
	83
	84	static inline unsigned int blkcipher_done_fast(struct blkcipher_walk *walk,
	85	unsigned int n)
	86	{
5cde0af2 HX	87	if (walk->flags & BLKCIPHER_WALK_COPY) {
	88	blkcipher_map_dst(walk);
	89	memcpy(walk->dst.virt.addr, walk->page, n);
	90	blkcipher_unmap_dst(walk);
	91	} else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
5cde0af2 HX	92	if (walk->flags & BLKCIPHER_WALK_DIFF)
5cde0af2 HX	93	blkcipher_unmap_dst(walk);
61ecdb80	94	blkcipher_unmap_src(walk);
5cde0af2 HX	95	}
	96
	97	scatterwalk_advance(&walk->in, n);
	98	scatterwalk_advance(&walk->out, n);
	99
	100	return n;
	101	}
	102
	103	int blkcipher_walk_done(struct blkcipher_desc *desc,
	104	struct blkcipher_walk *walk, int err)
	105	{
5cde0af2 HX	106	unsigned int nbytes = 0;
	107
	108	if (likely(err >= 0)) {
7607bd8f	109	unsigned int n = walk->nbytes - err;
5cde0af2 HX	110
5cde0af2 HX	111	if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW)))
7607bd8f HX	112	n = blkcipher_done_fast(walk, n);
	113	else if (WARN_ON(err)) {
	114	err = -EINVAL;
	115	goto err;
	116	} else
822be00f	117	n = blkcipher_done_slow(walk, n);
5cde0af2 HX	118
	119	nbytes = walk->total - n;
	120	err = 0;
	121	}
	122
	123	scatterwalk_done(&walk->in, 0, nbytes);
	124	scatterwalk_done(&walk->out, 1, nbytes);
	125
bac1b5c4	126	err:
5cde0af2 HX	127	walk->total = nbytes;
	128	walk->nbytes = nbytes;
	129
	130	if (nbytes) {
	131	crypto_yield(desc->flags);
	132	return blkcipher_walk_next(desc, walk);
	133	}
	134
	135	if (walk->iv != desc->info)
822be00f	136	memcpy(desc->info, walk->iv, walk->ivsize);
5cde0af2 HX	137	if (walk->buffer != walk->page)
	138	kfree(walk->buffer);
	139	if (walk->page)
	140	free_page((unsigned long)walk->page);
	141
	142	return err;
	143	}
	144	EXPORT_SYMBOL_GPL(blkcipher_walk_done);
	145
	146	static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
	147	struct blkcipher_walk *walk,
	148	unsigned int bsize,
	149	unsigned int alignmask)
	150	{
	151	unsigned int n;
70613783	152	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
5cde0af2 HX	153
	154	if (walk->buffer)
	155	goto ok;
	156
	157	walk->buffer = walk->page;
	158	if (walk->buffer)
	159	goto ok;
	160
2614de1b	161	n = aligned_bsize * 3 - (alignmask + 1) +
e4630f9f	162	(alignmask & ~(crypto_tfm_ctx_alignment() - 1));
5cde0af2 HX	163	walk->buffer = kmalloc(n, GFP_ATOMIC);
	164	if (!walk->buffer)
	165	return blkcipher_walk_done(desc, walk, -ENOMEM);
	166
	167	ok:
	168	walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
	169	alignmask + 1);
	170	walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
70613783 HX	171	walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr +
70613783 HX	172	aligned_bsize, bsize);
5cde0af2 HX	173
	174	scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
	175
	176	walk->nbytes = bsize;
	177	walk->flags \|= BLKCIPHER_WALK_SLOW;
	178
	179	return 0;
	180	}
	181
	182	static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
	183	{
	184	u8 *tmp = walk->page;
	185
	186	blkcipher_map_src(walk);
	187	memcpy(tmp, walk->src.virt.addr, walk->nbytes);
	188	blkcipher_unmap_src(walk);
	189
	190	walk->src.virt.addr = tmp;
	191	walk->dst.virt.addr = tmp;
	192
	193	return 0;
	194	}
	195
	196	static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
	197	struct blkcipher_walk *walk)
	198	{
	199	unsigned long diff;
	200
	201	walk->src.phys.page = scatterwalk_page(&walk->in);
	202	walk->src.phys.offset = offset_in_page(walk->in.offset);
	203	walk->dst.phys.page = scatterwalk_page(&walk->out);
	204	walk->dst.phys.offset = offset_in_page(walk->out.offset);
	205
	206	if (walk->flags & BLKCIPHER_WALK_PHYS)
	207	return 0;
	208
	209	diff = walk->src.phys.offset - walk->dst.phys.offset;
	210	diff \|= walk->src.virt.page - walk->dst.virt.page;
	211
	212	blkcipher_map_src(walk);
	213	walk->dst.virt.addr = walk->src.virt.addr;
	214
	215	if (diff) {
	216	walk->flags \|= BLKCIPHER_WALK_DIFF;
	217	blkcipher_map_dst(walk);
	218	}
	219
	220	return 0;
	221	}
	222
	223	static int blkcipher_walk_next(struct blkcipher_desc *desc,
	224	struct blkcipher_walk *walk)
	225	{
7607bd8f	226	unsigned int bsize;
5cde0af2 HX	227	unsigned int n;
	228	int err;
	229
	230	n = walk->total;
822be00f	231	if (unlikely(n < walk->cipher_blocksize)) {
5cde0af2 HX	232	desc->flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
	233	return blkcipher_walk_done(desc, walk, -EINVAL);
	234	}
	235
acdb04d0 HX	236	bsize = min(walk->walk_blocksize, n);
acdb04d0 HX	237
5cde0af2 HX	238	walk->flags &= ~(BLKCIPHER_WALK_SLOW \| BLKCIPHER_WALK_COPY \|
5cde0af2 HX	239	BLKCIPHER_WALK_DIFF);
822be00f AB	240	if (!scatterwalk_aligned(&walk->in, walk->alignmask) \|\|
822be00f AB	241	!scatterwalk_aligned(&walk->out, walk->alignmask)) {
5cde0af2 HX	242	walk->flags \|= BLKCIPHER_WALK_COPY;
	243	if (!walk->page) {
	244	walk->page = (void *)__get_free_page(GFP_ATOMIC);
	245	if (!walk->page)
	246	n = 0;
	247	}
	248	}
	249
	250	n = scatterwalk_clamp(&walk->in, n);
	251	n = scatterwalk_clamp(&walk->out, n);
	252
	253	if (unlikely(n < bsize)) {
822be00f	254	err = blkcipher_next_slow(desc, walk, bsize, walk->alignmask);
5cde0af2 HX	255	goto set_phys_lowmem;
	256	}
	257
	258	walk->nbytes = n;
	259	if (walk->flags & BLKCIPHER_WALK_COPY) {
	260	err = blkcipher_next_copy(walk);
	261	goto set_phys_lowmem;
	262	}
	263
	264	return blkcipher_next_fast(desc, walk);
	265
	266	set_phys_lowmem:
	267	if (walk->flags & BLKCIPHER_WALK_PHYS) {
	268	walk->src.phys.page = virt_to_page(walk->src.virt.addr);
	269	walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
	270	walk->src.phys.offset &= PAGE_SIZE - 1;
	271	walk->dst.phys.offset &= PAGE_SIZE - 1;
	272	}
	273	return err;
	274	}
	275
822be00f	276	static inline int blkcipher_copy_iv(struct blkcipher_walk *walk)
5cde0af2	277	{
822be00f AB	278	unsigned bs = walk->walk_blocksize;
	279	unsigned aligned_bs = ALIGN(bs, walk->alignmask + 1);
	280	unsigned int size = aligned_bs * 2 +
	281	walk->ivsize + max(aligned_bs, walk->ivsize) -
	282	(walk->alignmask + 1);
5cde0af2 HX	283	u8 *iv;
5cde0af2 HX	284
822be00f	285	size += walk->alignmask & ~(crypto_tfm_ctx_alignment() - 1);
5cde0af2 HX	286	walk->buffer = kmalloc(size, GFP_ATOMIC);
	287	if (!walk->buffer)
	288	return -ENOMEM;
	289
822be00f	290	iv = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
70613783 HX	291	iv = blkcipher_get_spot(iv, bs) + aligned_bs;
70613783 HX	292	iv = blkcipher_get_spot(iv, bs) + aligned_bs;
822be00f	293	iv = blkcipher_get_spot(iv, walk->ivsize);
5cde0af2	294
822be00f	295	walk->iv = memcpy(iv, walk->iv, walk->ivsize);
5cde0af2 HX	296	return 0;
	297	}
	298
	299	int blkcipher_walk_virt(struct blkcipher_desc *desc,
	300	struct blkcipher_walk *walk)
	301	{
	302	walk->flags &= ~BLKCIPHER_WALK_PHYS;
822be00f AB	303	walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	304	walk->cipher_blocksize = walk->walk_blocksize;
	305	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	306	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
5cde0af2 HX	307	return blkcipher_walk_first(desc, walk);
	308	}
	309	EXPORT_SYMBOL_GPL(blkcipher_walk_virt);
	310
	311	int blkcipher_walk_phys(struct blkcipher_desc *desc,
	312	struct blkcipher_walk *walk)
	313	{
	314	walk->flags \|= BLKCIPHER_WALK_PHYS;
822be00f AB	315	walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	316	walk->cipher_blocksize = walk->walk_blocksize;
	317	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	318	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
5cde0af2 HX	319	return blkcipher_walk_first(desc, walk);
	320	}
	321	EXPORT_SYMBOL_GPL(blkcipher_walk_phys);
	322
	323	static int blkcipher_walk_first(struct blkcipher_desc *desc,
	324	struct blkcipher_walk *walk)
	325	{
fb469840 HX	326	if (WARN_ON_ONCE(in_irq()))
	327	return -EDEADLK;
	328
70d906bc	329	walk->iv = desc->info;
5cde0af2 HX	330	walk->nbytes = walk->total;
	331	if (unlikely(!walk->total))
	332	return 0;
	333
	334	walk->buffer = NULL;
822be00f AB	335	if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
822be00f AB	336	int err = blkcipher_copy_iv(walk);
5cde0af2 HX	337	if (err)
	338	return err;
	339	}
	340
	341	scatterwalk_start(&walk->in, walk->in.sg);
	342	scatterwalk_start(&walk->out, walk->out.sg);
	343	walk->page = NULL;
	344
	345	return blkcipher_walk_next(desc, walk);
	346	}
	347
7607bd8f HX	348	int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
	349	struct blkcipher_walk *walk,
	350	unsigned int blocksize)
	351	{
	352	walk->flags &= ~BLKCIPHER_WALK_PHYS;
822be00f AB	353	walk->walk_blocksize = blocksize;
	354	walk->cipher_blocksize = crypto_blkcipher_blocksize(desc->tfm);
	355	walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
	356	walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
7607bd8f HX	357	return blkcipher_walk_first(desc, walk);
	358	}
	359	EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block);
	360
4f7f1d7c AB	361	int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc,
	362	struct blkcipher_walk *walk,
	363	struct crypto_aead *tfm,
	364	unsigned int blocksize)
	365	{
	366	walk->flags &= ~BLKCIPHER_WALK_PHYS;
	367	walk->walk_blocksize = blocksize;
	368	walk->cipher_blocksize = crypto_aead_blocksize(tfm);
	369	walk->ivsize = crypto_aead_ivsize(tfm);
	370	walk->alignmask = crypto_aead_alignmask(tfm);
	371	return blkcipher_walk_first(desc, walk);
	372	}
	373	EXPORT_SYMBOL_GPL(blkcipher_aead_walk_virt_block);
	374
791b4d5f HX	375	static int setkey_unaligned(struct crypto_tfm tfm, const u8 key,
791b4d5f HX	376	unsigned int keylen)
ca7c3938 SS	377	{
	378	struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
	379	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	380	int ret;
	381	u8 buffer, alignbuffer;
	382	unsigned long absize;
	383
	384	absize = keylen + alignmask;
	385	buffer = kmalloc(absize, GFP_ATOMIC);
	386	if (!buffer)
	387	return -ENOMEM;
	388
	389	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	390	memcpy(alignbuffer, key, keylen);
	391	ret = cipher->setkey(tfm, alignbuffer, keylen);
06817176	392	memset(alignbuffer, 0, keylen);
ca7c3938 SS	393	kfree(buffer);
	394	return ret;
	395	}
	396
791b4d5f	397	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
5cde0af2 HX	398	{
5cde0af2 HX	399	struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
ca7c3938	400	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
5cde0af2 HX	401
	402	if (keylen < cipher->min_keysize \|\| keylen > cipher->max_keysize) {
	403	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	404	return -EINVAL;
	405	}
	406
ca7c3938 SS	407	if ((unsigned long)key & alignmask)
	408	return setkey_unaligned(tfm, key, keylen);
	409
5cde0af2 HX	410	return cipher->setkey(tfm, key, keylen);
	411	}
	412
32e3983f HX	413	static int async_setkey(struct crypto_ablkcipher tfm, const u8 key,
	414	unsigned int keylen)
	415	{
	416	return setkey(crypto_ablkcipher_tfm(tfm), key, keylen);
	417	}
	418
	419	static int async_encrypt(struct ablkcipher_request *req)
	420	{
	421	struct crypto_tfm *tfm = req->base.tfm;
	422	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	423	struct blkcipher_desc desc = {
	424	.tfm = __crypto_blkcipher_cast(tfm),
	425	.info = req->info,
	426	.flags = req->base.flags,
	427	};
	428
	429
	430	return alg->encrypt(&desc, req->dst, req->src, req->nbytes);
	431	}
	432
	433	static int async_decrypt(struct ablkcipher_request *req)
	434	{
	435	struct crypto_tfm *tfm = req->base.tfm;
	436	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	437	struct blkcipher_desc desc = {
	438	.tfm = __crypto_blkcipher_cast(tfm),
	439	.info = req->info,
	440	.flags = req->base.flags,
	441	};
	442
	443	return alg->decrypt(&desc, req->dst, req->src, req->nbytes);
	444	}
	445
27d2a330 HX	446	static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type,
27d2a330 HX	447	u32 mask)
5cde0af2 HX	448	{
	449	struct blkcipher_alg *cipher = &alg->cra_blkcipher;
	450	unsigned int len = alg->cra_ctxsize;
	451
332f8840 HX	452	if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK &&
332f8840 HX	453	cipher->ivsize) {
5cde0af2 HX	454	len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
	455	len += cipher->ivsize;
	456	}
	457
	458	return len;
	459	}
	460
32e3983f HX	461	static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm)
	462	{
	463	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	464	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	465
	466	crt->setkey = async_setkey;
	467	crt->encrypt = async_encrypt;
	468	crt->decrypt = async_decrypt;
ecfc4329	469	crt->base = __crypto_ablkcipher_cast(tfm);
32e3983f HX	470	crt->ivsize = alg->ivsize;
	471
	472	return 0;
	473	}
	474
	475	static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm)
5cde0af2 HX	476	{
	477	struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
	478	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	479	unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
	480	unsigned long addr;
	481
5cde0af2 HX	482	crt->setkey = setkey;
	483	crt->encrypt = alg->encrypt;
	484	crt->decrypt = alg->decrypt;
	485
	486	addr = (unsigned long)crypto_tfm_ctx(tfm);
	487	addr = ALIGN(addr, align);
	488	addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
	489	crt->iv = (void *)addr;
	490
	491	return 0;
	492	}
	493
32e3983f HX	494	static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
	495	{
	496	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
	497
	498	if (alg->ivsize > PAGE_SIZE / 8)
	499	return -EINVAL;
	500
332f8840	501	if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK)
32e3983f HX	502	return crypto_init_blkcipher_ops_sync(tfm);
	503	else
	504	return crypto_init_blkcipher_ops_async(tfm);
	505	}
	506
3acc8473	507	#ifdef CONFIG_NET
50496a1f SK	508	static int crypto_blkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	509	{
	510	struct crypto_report_blkcipher rblkcipher;
	511
9a5467bf MK	512	strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
	513	strncpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "<default>",
	514	sizeof(rblkcipher.geniv));
50496a1f SK	515
	516	rblkcipher.blocksize = alg->cra_blocksize;
	517	rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
	518	rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
	519	rblkcipher.ivsize = alg->cra_blkcipher.ivsize;
	520
6662df33 DM	521	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	522	sizeof(struct crypto_report_blkcipher), &rblkcipher))
	523	goto nla_put_failure;
50496a1f SK	524	return 0;
	525
	526	nla_put_failure:
	527	return -EMSGSIZE;
	528	}
3acc8473 HX	529	#else
	530	static int crypto_blkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	531	{
	532	return -ENOSYS;
	533	}
	534	#endif
50496a1f	535
5cde0af2	536	static void crypto_blkcipher_show(struct seq_file m, struct crypto_alg alg)
03f5d8ce	537	__attribute__ ((unused));
5cde0af2 HX	538	static void crypto_blkcipher_show(struct seq_file m, struct crypto_alg alg)
	539	{
	540	seq_printf(m, "type : blkcipher\n");
	541	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	542	seq_printf(m, "min keysize : %u\n", alg->cra_blkcipher.min_keysize);
	543	seq_printf(m, "max keysize : %u\n", alg->cra_blkcipher.max_keysize);
	544	seq_printf(m, "ivsize : %u\n", alg->cra_blkcipher.ivsize);
23508e11 HX	545	seq_printf(m, "geniv : %s\n", alg->cra_blkcipher.geniv ?:
23508e11 HX	546	"<default>");
5cde0af2 HX	547	}
	548
	549	const struct crypto_type crypto_blkcipher_type = {
	550	.ctxsize = crypto_blkcipher_ctxsize,
	551	.init = crypto_init_blkcipher_ops,
	552	#ifdef CONFIG_PROC_FS
	553	.show = crypto_blkcipher_show,
	554	#endif
50496a1f	555	.report = crypto_blkcipher_report,
5cde0af2 HX	556	};
	557	EXPORT_SYMBOL_GPL(crypto_blkcipher_type);
	558
	559	MODULE_LICENSE("GPL");
	560	MODULE_DESCRIPTION("Generic block chaining cipher type");