[linux.git] / crypto / ablkcipher.c

/*
 * Asynchronous block chaining cipher operations.
 *
 * This is the asynchronous version of blkcipher.c indicating completion
 * via a callback.
 *
 * Copyright (c) 2006 Herbert Xu <[email protected]>
 *
 * 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/internal/skcipher.h>
#include <linux/cpumask.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/rtnetlink.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/cryptouser.h>
#include <net/netlink.h>

#include <crypto/scatterwalk.h>

#include "internal.h"

static const char *skcipher_default_geniv __read_mostly;

struct ablkcipher_buffer {
	struct list_head	entry;
	struct scatter_walk	dst;
	unsigned int		len;
	void			*data;
};

enum {
	ABLKCIPHER_WALK_SLOW = 1 << 0,
};

static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
{
	scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
}

void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
{
	struct ablkcipher_buffer *p, *tmp;

	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
		ablkcipher_buffer_write(p);
		list_del(&p->entry);
		kfree(p);
	}
}
EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);

static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
					  struct ablkcipher_buffer *p)
{
	p->dst = walk->out;
	list_add_tail(&p->entry, &walk->buffers);
}

/* 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 *ablkcipher_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 ablkcipher_done_slow(struct ablkcipher_walk *walk,
						unsigned int bsize)
{
	unsigned int n = bsize;

	for (;;) {
		unsigned int len_this_page = scatterwalk_pagelen(&walk->out);

		if (len_this_page > n)
			len_this_page = n;
		scatterwalk_advance(&walk->out, n);
		if (n == len_this_page)
			break;
		n -= len_this_page;
		scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg));
	}

	return bsize;
}

static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
						unsigned int n)
{
	scatterwalk_advance(&walk->in, n);
	scatterwalk_advance(&walk->out, n);

	return n;
}

static int ablkcipher_walk_next(struct ablkcipher_request *req,
				struct ablkcipher_walk *walk);

int ablkcipher_walk_done(struct ablkcipher_request *req,
			 struct ablkcipher_walk *walk, int err)
{
	struct crypto_tfm *tfm = req->base.tfm;
	unsigned int nbytes = 0;

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

		if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
			n = ablkcipher_done_fast(walk, n);
		else if (WARN_ON(err)) {
			err = -EINVAL;
			goto err;
		} else
			n = ablkcipher_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(req->base.flags);
		return ablkcipher_walk_next(req, walk);
	}

	if (walk->iv != req->info)
		memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
	kfree(walk->iv_buffer);

	return err;
}
EXPORT_SYMBOL_GPL(ablkcipher_walk_done);

static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
				       struct ablkcipher_walk *walk,
				       unsigned int bsize,
				       unsigned int alignmask,
				       void **src_p, void **dst_p)
{
	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
	struct ablkcipher_buffer *p;
	void *src, *dst, *base;
	unsigned int n;

	n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
	n += (aligned_bsize * 3 - (alignmask + 1) +
	      (alignmask & ~(crypto_tfm_ctx_alignment() - 1)));

	p = kmalloc(n, GFP_ATOMIC);
	if (!p)
		return ablkcipher_walk_done(req, walk, -ENOMEM);

	base = p + 1;

	dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
	src = dst = ablkcipher_get_spot(dst, bsize);

	p->len = bsize;
	p->data = dst;

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

	ablkcipher_queue_write(walk, p);

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

	*src_p = src;
	*dst_p = dst;

	return 0;
}

static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
				     struct crypto_tfm *tfm,
				     unsigned int alignmask)
{
	unsigned bs = walk->blocksize;
	unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
	unsigned aligned_bs = ALIGN(bs, alignmask + 1);
	unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
			    (alignmask + 1);
	u8 *iv;

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

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

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

static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
				       struct ablkcipher_walk *walk)
{
	walk->src.page = scatterwalk_page(&walk->in);
	walk->src.offset = offset_in_page(walk->in.offset);
	walk->dst.page = scatterwalk_page(&walk->out);
	walk->dst.offset = offset_in_page(walk->out.offset);

	return 0;
}

static int ablkcipher_walk_next(struct ablkcipher_request *req,
				struct ablkcipher_walk *walk)
{
	struct crypto_tfm *tfm = req->base.tfm;
	unsigned int alignmask, bsize, n;
	void *src, *dst;
	int err;

	alignmask = crypto_tfm_alg_alignmask(tfm);
	n = walk->total;
	if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
		req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
		return ablkcipher_walk_done(req, walk, -EINVAL);
	}

	walk->flags &= ~ABLKCIPHER_WALK_SLOW;
	src = dst = NULL;

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

	if (n < bsize ||
	    !scatterwalk_aligned(&walk->in, alignmask) ||
	    !scatterwalk_aligned(&walk->out, alignmask)) {
		err = ablkcipher_next_slow(req, walk, bsize, alignmask,
					   &src, &dst);
		goto set_phys_lowmem;
	}

	walk->nbytes = n;

	return ablkcipher_next_fast(req, walk);

set_phys_lowmem:
	if (err >= 0) {
		walk->src.page = virt_to_page(src);
		walk->dst.page = virt_to_page(dst);
		walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
		walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
	}

	return err;
}

static int ablkcipher_walk_first(struct ablkcipher_request *req,
				 struct ablkcipher_walk *walk)
{
	struct crypto_tfm *tfm = req->base.tfm;
	unsigned int alignmask;

	alignmask = crypto_tfm_alg_alignmask(tfm);
	if (WARN_ON_ONCE(in_irq()))
		return -EDEADLK;

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

	walk->iv_buffer = NULL;
	walk->iv = req->info;
	if (unlikely(((unsigned long)walk->iv & alignmask))) {
		int err = ablkcipher_copy_iv(walk, tfm, alignmask);
		if (err)
			return err;
	}

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

	return ablkcipher_walk_next(req, walk);
}

int ablkcipher_walk_phys(struct ablkcipher_request *req,
			 struct ablkcipher_walk *walk)
{
	walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
	return ablkcipher_walk_first(req, walk);
}
EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);

static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
			    unsigned int keylen)
{
	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	unsigned long alignmask = crypto_ablkcipher_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_ablkcipher *tfm, const u8 *key,
		  unsigned int keylen)
{
	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);

	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
		crypto_ablkcipher_set_flags(tfm, 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 unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
					      u32 mask)
{
	return alg->cra_ctxsize;
}

int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
{
	return crypto_ablkcipher_encrypt(&req->creq);
}

int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
{
	return crypto_ablkcipher_decrypt(&req->creq);
}

static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
				      u32 mask)
{
	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;

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

	crt->setkey = setkey;
	crt->encrypt = alg->encrypt;
	crt->decrypt = alg->decrypt;
	if (!alg->ivsize) {
		crt->givencrypt = skcipher_null_givencrypt;
		crt->givdecrypt = skcipher_null_givdecrypt;
	}
	crt->base = __crypto_ablkcipher_cast(tfm);
	crt->ivsize = alg->ivsize;

	return 0;
}

static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_blkcipher rblkcipher;

	snprintf(rblkcipher.type, CRYPTO_MAX_ALG_NAME, "%s", "ablkcipher");
	snprintf(rblkcipher.geniv, CRYPTO_MAX_ALG_NAME, "%s",
		 alg->cra_ablkcipher.geniv ?: "<default>");

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

	NLA_PUT(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
		sizeof(struct crypto_report_blkcipher), &rblkcipher);

	return 0;

nla_put_failure:
	return -EMSGSIZE;
}

static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));
static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;

	seq_printf(m, "type         : ablkcipher\n");
	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
					     "yes" : "no");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<default>");
}

const struct crypto_type crypto_ablkcipher_type = {
	.ctxsize = crypto_ablkcipher_ctxsize,
	.init = crypto_init_ablkcipher_ops,
#ifdef CONFIG_PROC_FS
	.show = crypto_ablkcipher_show,
#endif
	.report = crypto_ablkcipher_report,
};
EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);

static int no_givdecrypt(struct skcipher_givcrypt_request *req)
{
	return -ENOSYS;
}

static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
				      u32 mask)
{
	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;

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

	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
		      alg->setkey : setkey;
	crt->encrypt = alg->encrypt;
	crt->decrypt = alg->decrypt;
	crt->givencrypt = alg->givencrypt;
	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
	crt->base = __crypto_ablkcipher_cast(tfm);
	crt->ivsize = alg->ivsize;

	return 0;
}

static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_blkcipher rblkcipher;

	snprintf(rblkcipher.type, CRYPTO_MAX_ALG_NAME, "%s", "givcipher");
	snprintf(rblkcipher.geniv, CRYPTO_MAX_ALG_NAME, "%s",
		 alg->cra_ablkcipher.geniv ?: "<built-in>");

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

	NLA_PUT(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
		sizeof(struct crypto_report_blkcipher), &rblkcipher);

	return 0;

nla_put_failure:
	return -EMSGSIZE;
}

static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));
static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;

	seq_printf(m, "type         : givcipher\n");
	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
					     "yes" : "no");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
	seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
	seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
	seq_printf(m, "geniv        : %s\n", ablkcipher->geniv ?: "<built-in>");
}

const struct crypto_type crypto_givcipher_type = {
	.ctxsize = crypto_ablkcipher_ctxsize,
	.init = crypto_init_givcipher_ops,
#ifdef CONFIG_PROC_FS
	.show = crypto_givcipher_show,
#endif
	.report = crypto_givcipher_report,
};
EXPORT_SYMBOL_GPL(crypto_givcipher_type);

const char *crypto_default_geniv(const struct crypto_alg *alg)
{
	if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	     CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
					 alg->cra_ablkcipher.ivsize) !=
	    alg->cra_blocksize)
		return "chainiv";

	return alg->cra_flags & CRYPTO_ALG_ASYNC ?
	       "eseqiv" : skcipher_default_geniv;
}

static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
{
	struct rtattr *tb[3];
	struct {
		struct rtattr attr;
		struct crypto_attr_type data;
	} ptype;
	struct {
		struct rtattr attr;
		struct crypto_attr_alg data;
	} palg;
	struct crypto_template *tmpl;
	struct crypto_instance *inst;
	struct crypto_alg *larval;
	const char *geniv;
	int err;

	larval = crypto_larval_lookup(alg->cra_driver_name,
				      (type & ~CRYPTO_ALG_TYPE_MASK) |
				      CRYPTO_ALG_TYPE_GIVCIPHER,
				      mask | CRYPTO_ALG_TYPE_MASK);
	err = PTR_ERR(larval);
	if (IS_ERR(larval))
		goto out;

	err = -EAGAIN;
	if (!crypto_is_larval(larval))
		goto drop_larval;

	ptype.attr.rta_len = sizeof(ptype);
	ptype.attr.rta_type = CRYPTOA_TYPE;
	ptype.data.type = type | CRYPTO_ALG_GENIV;
	/* GENIV tells the template that we're making a default geniv. */
	ptype.data.mask = mask | CRYPTO_ALG_GENIV;
	tb[0] = &ptype.attr;

	palg.attr.rta_len = sizeof(palg);
	palg.attr.rta_type = CRYPTOA_ALG;
	/* Must use the exact name to locate ourselves. */
	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
	tb[1] = &palg.attr;

	tb[2] = NULL;

	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	    CRYPTO_ALG_TYPE_BLKCIPHER)
		geniv = alg->cra_blkcipher.geniv;
	else
		geniv = alg->cra_ablkcipher.geniv;

	if (!geniv)
		geniv = crypto_default_geniv(alg);

	tmpl = crypto_lookup_template(geniv);
	err = -ENOENT;
	if (!tmpl)
		goto kill_larval;

	inst = tmpl->alloc(tb);
	err = PTR_ERR(inst);
	if (IS_ERR(inst))
		goto put_tmpl;

	if ((err = crypto_register_instance(tmpl, inst))) {
		tmpl->free(inst);
		goto put_tmpl;
	}

	/* Redo the lookup to use the instance we just registered. */
	err = -EAGAIN;

put_tmpl:
	crypto_tmpl_put(tmpl);
kill_larval:
	crypto_larval_kill(larval);
drop_larval:
	crypto_mod_put(larval);
out:
	crypto_mod_put(alg);
	return err;
}

static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
						 u32 mask)
{
	struct crypto_alg *alg;

	alg = crypto_alg_mod_lookup(name, type, mask);
	if (IS_ERR(alg))
		return alg;

	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	    CRYPTO_ALG_TYPE_GIVCIPHER)
		return alg;

	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	      CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
					  alg->cra_ablkcipher.ivsize))
		return alg;

	crypto_mod_put(alg);
	alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
				    mask & ~CRYPTO_ALG_TESTED);
	if (IS_ERR(alg))
		return alg;

	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	    CRYPTO_ALG_TYPE_GIVCIPHER) {
		if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
			crypto_mod_put(alg);
			alg = ERR_PTR(-ENOENT);
		}
		return alg;
	}

	BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
		 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
					     alg->cra_ablkcipher.ivsize));

	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
}

int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
			 u32 type, u32 mask)
{
	struct crypto_alg *alg;
	int err;

	type = crypto_skcipher_type(type);
	mask = crypto_skcipher_mask(mask);

	alg = crypto_lookup_skcipher(name, type, mask);
	if (IS_ERR(alg))
		return PTR_ERR(alg);

	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
	crypto_mod_put(alg);
	return err;
}
EXPORT_SYMBOL_GPL(crypto_grab_skcipher);

struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
						  u32 type, u32 mask)
{
	struct crypto_tfm *tfm;
	int err;

	type = crypto_skcipher_type(type);
	mask = crypto_skcipher_mask(mask);

	for (;;) {
		struct crypto_alg *alg;

		alg = crypto_lookup_skcipher(alg_name, type, mask);
		if (IS_ERR(alg)) {
			err = PTR_ERR(alg);
			goto err;
		}

		tfm = __crypto_alloc_tfm(alg, type, mask);
		if (!IS_ERR(tfm))
			return __crypto_ablkcipher_cast(tfm);

		crypto_mod_put(alg);
		err = PTR_ERR(tfm);

err:
		if (err != -EAGAIN)
			break;
		if (signal_pending(current)) {
			err = -EINTR;
			break;
		}
	}

	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);

static int __init skcipher_module_init(void)
{
	skcipher_default_geniv = num_possible_cpus() > 1 ?
				 "eseqiv" : "chainiv";
	return 0;
}

static void skcipher_module_exit(void)
{
}

module_init(skcipher_module_init);
module_exit(skcipher_module_exit);
Commit	Line	Data
b5b7f088 HX	1	/*
b5b7f088 HX	2	* Asynchronous block chaining cipher operations.
c4ede64a	3	*
b5b7f088 HX	4	* This is the asynchronous version of blkcipher.c indicating completion
	5	* via a callback.
	6	*
	7	* Copyright (c) 2006 Herbert Xu <[email protected]>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
c4ede64a	11	* Software Foundation; either version 2 of the License, or (at your option)
b5b7f088 HX	12	* any later version.
	13	*
	14	*/
	15
378f4f51	16	#include <crypto/internal/skcipher.h>
0b67fb65	17	#include <linux/cpumask.h>
378f4f51	18	#include <linux/err.h>
b5b7f088	19	#include <linux/init.h>
791b4d5f	20	#include <linux/kernel.h>
b5b7f088	21	#include <linux/module.h>
b9c55aa4 HX	22	#include <linux/rtnetlink.h>
b9c55aa4 HX	23	#include <linux/sched.h>
791b4d5f	24	#include <linux/slab.h>
b5b7f088	25	#include <linux/seq_file.h>
29ffc876 SK	26	#include <linux/cryptouser.h>
29ffc876 SK	27	#include <net/netlink.h>
b5b7f088	28
bf06099d DM	29	#include <crypto/scatterwalk.h>
bf06099d DM	30
378f4f51 HX	31	#include "internal.h"
378f4f51 HX	32
0b67fb65 HX	33	static const char *skcipher_default_geniv __read_mostly;
0b67fb65 HX	34
bf06099d DM	35	struct ablkcipher_buffer {
	36	struct list_head entry;
	37	struct scatter_walk dst;
	38	unsigned int len;
	39	void *data;
	40	};
	41
	42	enum {
	43	ABLKCIPHER_WALK_SLOW = 1 << 0,
	44	};
	45
	46	static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
	47	{
	48	scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
	49	}
	50
	51	void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
	52	{
	53	struct ablkcipher_buffer p, tmp;
	54
	55	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
	56	ablkcipher_buffer_write(p);
	57	list_del(&p->entry);
	58	kfree(p);
	59	}
	60	}
	61	EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);
	62
	63	static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
	64	struct ablkcipher_buffer *p)
	65	{
	66	p->dst = walk->out;
	67	list_add_tail(&p->entry, &walk->buffers);
	68	}
	69
	70	/* Get a spot of the specified length that does not straddle a page.
	71	* The caller needs to ensure that there is enough space for this operation.
	72	*/
	73	static inline u8 ablkcipher_get_spot(u8 start, unsigned int len)
	74	{
	75	u8 end_page = (u8 )(((unsigned long)(start + len - 1)) & PAGE_MASK);
	76	return max(start, end_page);
	77	}
	78
	79	static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
	80	unsigned int bsize)
	81	{
	82	unsigned int n = bsize;
	83
	84	for (;;) {
	85	unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
	86
	87	if (len_this_page > n)
	88	len_this_page = n;
	89	scatterwalk_advance(&walk->out, n);
	90	if (n == len_this_page)
	91	break;
	92	n -= len_this_page;
	93	scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg));
	94	}
	95
	96	return bsize;
	97	}
	98
99	static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
100	unsigned int n)
101	{
102	scatterwalk_advance(&walk->in, n);
103	scatterwalk_advance(&walk->out, n);
104
105	return n;
106	}
107
108	static int ablkcipher_walk_next(struct ablkcipher_request *req,
109	struct ablkcipher_walk *walk);
110
111	int ablkcipher_walk_done(struct ablkcipher_request *req,
112	struct ablkcipher_walk *walk, int err)
113	{
114	struct crypto_tfm *tfm = req->base.tfm;
115	unsigned int nbytes = 0;
116
117	if (likely(err >= 0)) {
118	unsigned int n = walk->nbytes - err;
119
120	if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
121	n = ablkcipher_done_fast(walk, n);
122	else if (WARN_ON(err)) {
123	err = -EINVAL;
124	goto err;
125	} else
126	n = ablkcipher_done_slow(walk, n);
127
128	nbytes = walk->total - n;
129	err = 0;
130	}
131
132	scatterwalk_done(&walk->in, 0, nbytes);
133	scatterwalk_done(&walk->out, 1, nbytes);
134
135	err:
136	walk->total = nbytes;
137	walk->nbytes = nbytes;
138
139	if (nbytes) {
140	crypto_yield(req->base.flags);
141	return ablkcipher_walk_next(req, walk);
142	}
143
144	if (walk->iv != req->info)
145	memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
33c7c0fb	146	kfree(walk->iv_buffer);
bf06099d DM	147
	148	return err;
	149	}
	150	EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
	151
	152	static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
	153	struct ablkcipher_walk *walk,
	154	unsigned int bsize,
	155	unsigned int alignmask,
	156	void src_p, void dst_p)
	157	{
	158	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
	159	struct ablkcipher_buffer *p;
	160	void src, dst, *base;
	161	unsigned int n;
	162
	163	n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
	164	n += (aligned_bsize * 3 - (alignmask + 1) +
	165	(alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
	166
	167	p = kmalloc(n, GFP_ATOMIC);
	168	if (!p)
2716fbf6	169	return ablkcipher_walk_done(req, walk, -ENOMEM);
bf06099d DM	170
	171	base = p + 1;
	172
	173	dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
	174	src = dst = ablkcipher_get_spot(dst, bsize);
	175
	176	p->len = bsize;
	177	p->data = dst;
	178
	179	scatterwalk_copychunks(src, &walk->in, bsize, 0);
	180
	181	ablkcipher_queue_write(walk, p);
	182
	183	walk->nbytes = bsize;
	184	walk->flags \|= ABLKCIPHER_WALK_SLOW;
	185
	186	*src_p = src;
	187	*dst_p = dst;
	188
	189	return 0;
	190	}
	191
	192	static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
	193	struct crypto_tfm *tfm,
	194	unsigned int alignmask)
	195	{
	196	unsigned bs = walk->blocksize;
	197	unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
	198	unsigned aligned_bs = ALIGN(bs, alignmask + 1);
	199	unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
	200	(alignmask + 1);
	201	u8 *iv;
	202
	203	size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
	204	walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
	205	if (!walk->iv_buffer)
	206	return -ENOMEM;
	207
	208	iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
	209	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
	210	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
	211	iv = ablkcipher_get_spot(iv, ivsize);
	212
	213	walk->iv = memcpy(iv, walk->iv, ivsize);
	214	return 0;
	215	}
	216
	217	static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
	218	struct ablkcipher_walk *walk)
	219	{
	220	walk->src.page = scatterwalk_page(&walk->in);
	221	walk->src.offset = offset_in_page(walk->in.offset);
	222	walk->dst.page = scatterwalk_page(&walk->out);
	223	walk->dst.offset = offset_in_page(walk->out.offset);
	224
	225	return 0;
	226	}
	227
	228	static int ablkcipher_walk_next(struct ablkcipher_request *req,
	229	struct ablkcipher_walk *walk)
	230	{
	231	struct crypto_tfm *tfm = req->base.tfm;
	232	unsigned int alignmask, bsize, n;
	233	void src, dst;
234	int err;
235
236	alignmask = crypto_tfm_alg_alignmask(tfm);
237	n = walk->total;
238	if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
239	req->base.flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
240	return ablkcipher_walk_done(req, walk, -EINVAL);
241	}
242
243	walk->flags &= ~ABLKCIPHER_WALK_SLOW;
244	src = dst = NULL;
245
246	bsize = min(walk->blocksize, n);
247	n = scatterwalk_clamp(&walk->in, n);
248	n = scatterwalk_clamp(&walk->out, n);
249
250	if (n < bsize \|\|
251	!scatterwalk_aligned(&walk->in, alignmask) \|\|
252	!scatterwalk_aligned(&walk->out, alignmask)) {
253	err = ablkcipher_next_slow(req, walk, bsize, alignmask,
254	&src, &dst);
255	goto set_phys_lowmem;
256	}
257
258	walk->nbytes = n;
259
260	return ablkcipher_next_fast(req, walk);
261
262	set_phys_lowmem:
263	if (err >= 0) {
264	walk->src.page = virt_to_page(src);
265	walk->dst.page = virt_to_page(dst);
266	walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
267	walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
268	}
269
270	return err;
271	}
272
273	static int ablkcipher_walk_first(struct ablkcipher_request *req,
274	struct ablkcipher_walk *walk)
275	{
276	struct crypto_tfm *tfm = req->base.tfm;
277	unsigned int alignmask;
278
279	alignmask = crypto_tfm_alg_alignmask(tfm);
280	if (WARN_ON_ONCE(in_irq()))
281	return -EDEADLK;
282
283	walk->nbytes = walk->total;
284	if (unlikely(!walk->total))
285	return 0;
286
287	walk->iv_buffer = NULL;
288	walk->iv = req->info;
289	if (unlikely(((unsigned long)walk->iv & alignmask))) {
290	int err = ablkcipher_copy_iv(walk, tfm, alignmask);
291	if (err)
292	return err;
293	}
294
295	scatterwalk_start(&walk->in, walk->in.sg);
296	scatterwalk_start(&walk->out, walk->out.sg);
297
298	return ablkcipher_walk_next(req, walk);
299	}
300
301	int ablkcipher_walk_phys(struct ablkcipher_request *req,
302	struct ablkcipher_walk *walk)
303	{
304	walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
305	return ablkcipher_walk_first(req, walk);
306	}
307	EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
308
791b4d5f HX	309	static int setkey_unaligned(struct crypto_ablkcipher tfm, const u8 key,
791b4d5f HX	310	unsigned int keylen)
ca7c3938 SS	311	{
	312	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	313	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
	314	int ret;
	315	u8 buffer, alignbuffer;
	316	unsigned long absize;
	317
	318	absize = keylen + alignmask;
	319	buffer = kmalloc(absize, GFP_ATOMIC);
	320	if (!buffer)
	321	return -ENOMEM;
	322
	323	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	324	memcpy(alignbuffer, key, keylen);
	325	ret = cipher->setkey(tfm, alignbuffer, keylen);
06817176	326	memset(alignbuffer, 0, keylen);
ca7c3938 SS	327	kfree(buffer);
	328	return ret;
	329	}
	330
b5b7f088 HX	331	static int setkey(struct crypto_ablkcipher tfm, const u8 key,
	332	unsigned int keylen)
	333	{
	334	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
ca7c3938	335	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
b5b7f088 HX	336
	337	if (keylen < cipher->min_keysize \|\| keylen > cipher->max_keysize) {
	338	crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	339	return -EINVAL;
	340	}
	341
ca7c3938 SS	342	if ((unsigned long)key & alignmask)
	343	return setkey_unaligned(tfm, key, keylen);
	344
b5b7f088 HX	345	return cipher->setkey(tfm, key, keylen);
	346	}
	347
	348	static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
	349	u32 mask)
	350	{
	351	return alg->cra_ctxsize;
	352	}
	353
b9c55aa4 HX	354	int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
	355	{
	356	return crypto_ablkcipher_encrypt(&req->creq);
	357	}
	358
	359	int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
	360	{
	361	return crypto_ablkcipher_decrypt(&req->creq);
	362	}
	363
b5b7f088 HX	364	static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
	365	u32 mask)
	366	{
	367	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	368	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	369
	370	if (alg->ivsize > PAGE_SIZE / 8)
	371	return -EINVAL;
	372
	373	crt->setkey = setkey;
	374	crt->encrypt = alg->encrypt;
	375	crt->decrypt = alg->decrypt;
b9c55aa4 HX	376	if (!alg->ivsize) {
	377	crt->givencrypt = skcipher_null_givencrypt;
	378	crt->givdecrypt = skcipher_null_givdecrypt;
	379	}
ecfc4329	380	crt->base = __crypto_ablkcipher_cast(tfm);
b5b7f088 HX	381	crt->ivsize = alg->ivsize;
	382
	383	return 0;
	384	}
	385
29ffc876 SK	386	static int crypto_ablkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	387	{
	388	struct crypto_report_blkcipher rblkcipher;
	389
	390	snprintf(rblkcipher.type, CRYPTO_MAX_ALG_NAME, "%s", "ablkcipher");
	391	snprintf(rblkcipher.geniv, CRYPTO_MAX_ALG_NAME, "%s",
	392	alg->cra_ablkcipher.geniv ?: "<default>");
	393
	394	rblkcipher.blocksize = alg->cra_blocksize;
	395	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
	396	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
	397	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
	398
	399	NLA_PUT(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	400	sizeof(struct crypto_report_blkcipher), &rblkcipher);
	401
	402	return 0;
	403
	404	nla_put_failure:
	405	return -EMSGSIZE;
	406	}
	407
b5b7f088 HX	408	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	409	__attribute__ ((unused));
	410	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	411	{
	412	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	413
	414	seq_printf(m, "type : ablkcipher\n");
189ed66e HX	415	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
189ed66e HX	416	"yes" : "no");
b5b7f088 HX	417	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	418	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	419	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	420	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	421	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
b5b7f088 HX	422	}
	423
	424	const struct crypto_type crypto_ablkcipher_type = {
	425	.ctxsize = crypto_ablkcipher_ctxsize,
	426	.init = crypto_init_ablkcipher_ops,
	427	#ifdef CONFIG_PROC_FS
	428	.show = crypto_ablkcipher_show,
	429	#endif
29ffc876	430	.report = crypto_ablkcipher_report,
b5b7f088 HX	431	};
	432	EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
	433
61da88e2 HX	434	static int no_givdecrypt(struct skcipher_givcrypt_request *req)
	435	{
	436	return -ENOSYS;
	437	}
	438
	439	static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
	440	u32 mask)
	441	{
	442	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	443	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	444
	445	if (alg->ivsize > PAGE_SIZE / 8)
	446	return -EINVAL;
	447
ecfc4329 HX	448	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
ecfc4329 HX	449	alg->setkey : setkey;
61da88e2 HX	450	crt->encrypt = alg->encrypt;
	451	crt->decrypt = alg->decrypt;
	452	crt->givencrypt = alg->givencrypt;
	453	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
ecfc4329	454	crt->base = __crypto_ablkcipher_cast(tfm);
61da88e2 HX	455	crt->ivsize = alg->ivsize;
	456
	457	return 0;
	458	}
	459
3e29c109 SK	460	static int crypto_givcipher_report(struct sk_buff skb, struct crypto_alg alg)
	461	{
	462	struct crypto_report_blkcipher rblkcipher;
	463
	464	snprintf(rblkcipher.type, CRYPTO_MAX_ALG_NAME, "%s", "givcipher");
	465	snprintf(rblkcipher.geniv, CRYPTO_MAX_ALG_NAME, "%s",
	466	alg->cra_ablkcipher.geniv ?: "<built-in>");
	467
	468	rblkcipher.blocksize = alg->cra_blocksize;
	469	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
	470	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
	471	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
	472
	473	NLA_PUT(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	474	sizeof(struct crypto_report_blkcipher), &rblkcipher);
	475
	476	return 0;
	477
	478	nla_put_failure:
	479	return -EMSGSIZE;
	480	}
	481
61da88e2 HX	482	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	483	__attribute__ ((unused));
	484	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	485	{
	486	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	487
	488	seq_printf(m, "type : givcipher\n");
189ed66e HX	489	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
189ed66e HX	490	"yes" : "no");
61da88e2 HX	491	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	492	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	493	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	494	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	495	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
61da88e2 HX	496	}
	497
	498	const struct crypto_type crypto_givcipher_type = {
	499	.ctxsize = crypto_ablkcipher_ctxsize,
	500	.init = crypto_init_givcipher_ops,
	501	#ifdef CONFIG_PROC_FS
	502	.show = crypto_givcipher_show,
	503	#endif
3e29c109	504	.report = crypto_givcipher_report,
61da88e2 HX	505	};
	506	EXPORT_SYMBOL_GPL(crypto_givcipher_type);
	507
ecfc4329 HX	508	const char crypto_default_geniv(const struct crypto_alg alg)
ecfc4329 HX	509	{
63b5ac28 HX	510	if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	511	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	512	alg->cra_ablkcipher.ivsize) !=
	513	alg->cra_blocksize)
	514	return "chainiv";
	515
0b67fb65 HX	516	return alg->cra_flags & CRYPTO_ALG_ASYNC ?
0b67fb65 HX	517	"eseqiv" : skcipher_default_geniv;
ecfc4329 HX	518	}
ecfc4329 HX	519
b9c55aa4 HX	520	static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
	521	{
	522	struct rtattr *tb[3];
	523	struct {
	524	struct rtattr attr;
	525	struct crypto_attr_type data;
	526	} ptype;
	527	struct {
	528	struct rtattr attr;
	529	struct crypto_attr_alg data;
	530	} palg;
	531	struct crypto_template *tmpl;
	532	struct crypto_instance *inst;
	533	struct crypto_alg *larval;
	534	const char *geniv;
	535	int err;
	536
	537	larval = crypto_larval_lookup(alg->cra_driver_name,
435578ae	538	(type & ~CRYPTO_ALG_TYPE_MASK) \|
b9c55aa4	539	CRYPTO_ALG_TYPE_GIVCIPHER,
435578ae	540	mask \| CRYPTO_ALG_TYPE_MASK);
b9c55aa4 HX	541	err = PTR_ERR(larval);
	542	if (IS_ERR(larval))
	543	goto out;
	544
	545	err = -EAGAIN;
	546	if (!crypto_is_larval(larval))
	547	goto drop_larval;
	548
	549	ptype.attr.rta_len = sizeof(ptype);
	550	ptype.attr.rta_type = CRYPTOA_TYPE;
	551	ptype.data.type = type \| CRYPTO_ALG_GENIV;
	552	/* GENIV tells the template that we're making a default geniv. */
	553	ptype.data.mask = mask \| CRYPTO_ALG_GENIV;
	554	tb[0] = &ptype.attr;
	555
	556	palg.attr.rta_len = sizeof(palg);
	557	palg.attr.rta_type = CRYPTOA_ALG;
	558	/* Must use the exact name to locate ourselves. */
	559	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
	560	tb[1] = &palg.attr;
	561
	562	tb[2] = NULL;
	563
	564	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	565	CRYPTO_ALG_TYPE_BLKCIPHER)
	566	geniv = alg->cra_blkcipher.geniv;
	567	else
	568	geniv = alg->cra_ablkcipher.geniv;
	569
	570	if (!geniv)
	571	geniv = crypto_default_geniv(alg);
	572
	573	tmpl = crypto_lookup_template(geniv);
	574	err = -ENOENT;
	575	if (!tmpl)
	576	goto kill_larval;
	577
	578	inst = tmpl->alloc(tb);
	579	err = PTR_ERR(inst);
	580	if (IS_ERR(inst))
	581	goto put_tmpl;
	582
	583	if ((err = crypto_register_instance(tmpl, inst))) {
	584	tmpl->free(inst);
	585	goto put_tmpl;
	586	}
	587
	588	/* Redo the lookup to use the instance we just registered. */
	589	err = -EAGAIN;
	590
	591	put_tmpl:
	592	crypto_tmpl_put(tmpl);
	593	kill_larval:
	594	crypto_larval_kill(larval);
	595	drop_larval:
	596	crypto_mod_put(larval);
	597	out:
	598	crypto_mod_put(alg);
	599	return err;
	600	}
	601
	602	static struct crypto_alg crypto_lookup_skcipher(const char name, u32 type,
	603	u32 mask)
	604	{
605	struct crypto_alg *alg;
606
607	alg = crypto_alg_mod_lookup(name, type, mask);
608	if (IS_ERR(alg))
609	return alg;
610
611	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
612	CRYPTO_ALG_TYPE_GIVCIPHER)
613	return alg;
614
615	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
616	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
617	alg->cra_ablkcipher.ivsize))
618	return alg;
619
b170a137 HX	620	crypto_mod_put(alg);
	621	alg = crypto_alg_mod_lookup(name, type \| CRYPTO_ALG_TESTED,
	622	mask & ~CRYPTO_ALG_TESTED);
	623	if (IS_ERR(alg))
	624	return alg;
	625
	626	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	627	CRYPTO_ALG_TYPE_GIVCIPHER) {
	628	if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
	629	crypto_mod_put(alg);
	630	alg = ERR_PTR(-ENOENT);
	631	}
	632	return alg;
	633	}
	634
	635	BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	636	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	637	alg->cra_ablkcipher.ivsize));
	638
b9c55aa4 HX	639	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
	640	}
	641
378f4f51 HX	642	int crypto_grab_skcipher(struct crypto_skcipher_spawn spawn, const char name,
	643	u32 type, u32 mask)
	644	{
	645	struct crypto_alg *alg;
	646	int err;
	647
	648	type = crypto_skcipher_type(type);
	649	mask = crypto_skcipher_mask(mask);
	650
b9c55aa4	651	alg = crypto_lookup_skcipher(name, type, mask);
378f4f51 HX	652	if (IS_ERR(alg))
	653	return PTR_ERR(alg);
	654
	655	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
	656	crypto_mod_put(alg);
	657	return err;
	658	}
	659	EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
	660
b9c55aa4 HX	661	struct crypto_ablkcipher crypto_alloc_ablkcipher(const char alg_name,
	662	u32 type, u32 mask)
	663	{
	664	struct crypto_tfm *tfm;
	665	int err;
	666
	667	type = crypto_skcipher_type(type);
	668	mask = crypto_skcipher_mask(mask);
	669
	670	for (;;) {
	671	struct crypto_alg *alg;
	672
	673	alg = crypto_lookup_skcipher(alg_name, type, mask);
	674	if (IS_ERR(alg)) {
	675	err = PTR_ERR(alg);
	676	goto err;
	677	}
	678
	679	tfm = __crypto_alloc_tfm(alg, type, mask);
	680	if (!IS_ERR(tfm))
	681	return __crypto_ablkcipher_cast(tfm);
	682
	683	crypto_mod_put(alg);
	684	err = PTR_ERR(tfm);
	685
	686	err:
	687	if (err != -EAGAIN)
	688	break;
	689	if (signal_pending(current)) {
	690	err = -EINTR;
	691	break;
	692	}
	693	}
	694
	695	return ERR_PTR(err);
	696	}
	697	EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);
0b67fb65 HX	698
	699	static int __init skcipher_module_init(void)
	700	{
	701	skcipher_default_geniv = num_possible_cpus() > 1 ?
	702	"eseqiv" : "chainiv";
	703	return 0;
	704	}
	705
	706	static void skcipher_module_exit(void)
	707	{
	708	}
	709
	710	module_init(skcipher_module_init);
	711	module_exit(skcipher_module_exit);