[linux-2.6-block.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 <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/internal/skcipher.h>
#include <linux/cpumask.h>
#include <linux/err.h>
#include <linux/kernel.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"

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;
}

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

	strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
		sizeof(rblkcipher.geniv));

	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;

	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_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	return -ENOSYS;
}
#endif

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;
}

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

	strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
		sizeof(rblkcipher.geniv));

	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;

	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_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	return -ENOSYS;
}
#endif

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 "eseqiv";
}

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;
}

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));
}
EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);

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);
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 <herbert@gondor.apana.org.au>
	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>
791b4d5f	19	#include <linux/kernel.h>
b9c55aa4 HX	20	#include <linux/rtnetlink.h>
b9c55aa4 HX	21	#include <linux/sched.h>
791b4d5f	22	#include <linux/slab.h>
b5b7f088	23	#include <linux/seq_file.h>
29ffc876 SK	24	#include <linux/cryptouser.h>
29ffc876 SK	25	#include <net/netlink.h>
b5b7f088	26
bf06099d DM	27	#include <crypto/scatterwalk.h>
bf06099d DM	28
378f4f51 HX	29	#include "internal.h"
378f4f51 HX	30
bf06099d DM	31	struct ablkcipher_buffer {
	32	struct list_head entry;
	33	struct scatter_walk dst;
	34	unsigned int len;
	35	void *data;
	36	};
	37
	38	enum {
	39	ABLKCIPHER_WALK_SLOW = 1 << 0,
	40	};
	41
	42	static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
	43	{
	44	scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
	45	}
	46
	47	void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
	48	{
	49	struct ablkcipher_buffer p, tmp;
	50
	51	list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
	52	ablkcipher_buffer_write(p);
	53	list_del(&p->entry);
	54	kfree(p);
	55	}
	56	}
	57	EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);
	58
	59	static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
	60	struct ablkcipher_buffer *p)
	61	{
	62	p->dst = walk->out;
	63	list_add_tail(&p->entry, &walk->buffers);
	64	}
	65
	66	/* Get a spot of the specified length that does not straddle a page.
	67	* The caller needs to ensure that there is enough space for this operation.
	68	*/
	69	static inline u8 ablkcipher_get_spot(u8 start, unsigned int len)
	70	{
	71	u8 end_page = (u8 )(((unsigned long)(start + len - 1)) & PAGE_MASK);
	72	return max(start, end_page);
	73	}
	74
	75	static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
	76	unsigned int bsize)
	77	{
	78	unsigned int n = bsize;
	79
	80	for (;;) {
	81	unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
	82
	83	if (len_this_page > n)
	84	len_this_page = n;
	85	scatterwalk_advance(&walk->out, n);
	86	if (n == len_this_page)
	87	break;
	88	n -= len_this_page;
	89	scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg));
	90	}
	91
	92	return bsize;
	93	}
	94
95	static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
96	unsigned int n)
97	{
98	scatterwalk_advance(&walk->in, n);
99	scatterwalk_advance(&walk->out, n);
100
101	return n;
102	}
103
104	static int ablkcipher_walk_next(struct ablkcipher_request *req,
105	struct ablkcipher_walk *walk);
106
107	int ablkcipher_walk_done(struct ablkcipher_request *req,
108	struct ablkcipher_walk *walk, int err)
109	{
110	struct crypto_tfm *tfm = req->base.tfm;
111	unsigned int nbytes = 0;
112
113	if (likely(err >= 0)) {
114	unsigned int n = walk->nbytes - err;
115
116	if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
117	n = ablkcipher_done_fast(walk, n);
118	else if (WARN_ON(err)) {
119	err = -EINVAL;
120	goto err;
121	} else
122	n = ablkcipher_done_slow(walk, n);
123
124	nbytes = walk->total - n;
125	err = 0;
126	}
127
128	scatterwalk_done(&walk->in, 0, nbytes);
129	scatterwalk_done(&walk->out, 1, nbytes);
130
131	err:
132	walk->total = nbytes;
133	walk->nbytes = nbytes;
134
135	if (nbytes) {
136	crypto_yield(req->base.flags);
137	return ablkcipher_walk_next(req, walk);
138	}
139
140	if (walk->iv != req->info)
141	memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
33c7c0fb	142	kfree(walk->iv_buffer);
bf06099d DM	143
	144	return err;
	145	}
	146	EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
	147
	148	static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
	149	struct ablkcipher_walk *walk,
	150	unsigned int bsize,
	151	unsigned int alignmask,
	152	void src_p, void dst_p)
	153	{
	154	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
	155	struct ablkcipher_buffer *p;
	156	void src, dst, *base;
	157	unsigned int n;
	158
	159	n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
	160	n += (aligned_bsize * 3 - (alignmask + 1) +
	161	(alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
	162
	163	p = kmalloc(n, GFP_ATOMIC);
	164	if (!p)
2716fbf6	165	return ablkcipher_walk_done(req, walk, -ENOMEM);
bf06099d DM	166
	167	base = p + 1;
	168
	169	dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
	170	src = dst = ablkcipher_get_spot(dst, bsize);
	171
	172	p->len = bsize;
	173	p->data = dst;
	174
	175	scatterwalk_copychunks(src, &walk->in, bsize, 0);
	176
	177	ablkcipher_queue_write(walk, p);
	178
	179	walk->nbytes = bsize;
	180	walk->flags \|= ABLKCIPHER_WALK_SLOW;
	181
	182	*src_p = src;
	183	*dst_p = dst;
	184
	185	return 0;
	186	}
	187
	188	static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
	189	struct crypto_tfm *tfm,
	190	unsigned int alignmask)
	191	{
	192	unsigned bs = walk->blocksize;
	193	unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
	194	unsigned aligned_bs = ALIGN(bs, alignmask + 1);
	195	unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
	196	(alignmask + 1);
	197	u8 *iv;
	198
	199	size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
	200	walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
	201	if (!walk->iv_buffer)
	202	return -ENOMEM;
	203
	204	iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
	205	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
	206	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
	207	iv = ablkcipher_get_spot(iv, ivsize);
	208
	209	walk->iv = memcpy(iv, walk->iv, ivsize);
	210	return 0;
	211	}
	212
	213	static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
	214	struct ablkcipher_walk *walk)
	215	{
	216	walk->src.page = scatterwalk_page(&walk->in);
	217	walk->src.offset = offset_in_page(walk->in.offset);
	218	walk->dst.page = scatterwalk_page(&walk->out);
	219	walk->dst.offset = offset_in_page(walk->out.offset);
	220
	221	return 0;
	222	}
	223
	224	static int ablkcipher_walk_next(struct ablkcipher_request *req,
	225	struct ablkcipher_walk *walk)
	226	{
	227	struct crypto_tfm *tfm = req->base.tfm;
	228	unsigned int alignmask, bsize, n;
	229	void src, dst;
230	int err;
231
232	alignmask = crypto_tfm_alg_alignmask(tfm);
233	n = walk->total;
234	if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
235	req->base.flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
236	return ablkcipher_walk_done(req, walk, -EINVAL);
237	}
238
239	walk->flags &= ~ABLKCIPHER_WALK_SLOW;
240	src = dst = NULL;
241
242	bsize = min(walk->blocksize, n);
243	n = scatterwalk_clamp(&walk->in, n);
244	n = scatterwalk_clamp(&walk->out, n);
245
246	if (n < bsize \|\|
247	!scatterwalk_aligned(&walk->in, alignmask) \|\|
248	!scatterwalk_aligned(&walk->out, alignmask)) {
249	err = ablkcipher_next_slow(req, walk, bsize, alignmask,
250	&src, &dst);
251	goto set_phys_lowmem;
252	}
253
254	walk->nbytes = n;
255
256	return ablkcipher_next_fast(req, walk);
257
258	set_phys_lowmem:
259	if (err >= 0) {
260	walk->src.page = virt_to_page(src);
261	walk->dst.page = virt_to_page(dst);
262	walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
263	walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
264	}
265
266	return err;
267	}
268
269	static int ablkcipher_walk_first(struct ablkcipher_request *req,
270	struct ablkcipher_walk *walk)
271	{
272	struct crypto_tfm *tfm = req->base.tfm;
273	unsigned int alignmask;
274
275	alignmask = crypto_tfm_alg_alignmask(tfm);
276	if (WARN_ON_ONCE(in_irq()))
277	return -EDEADLK;
278
279	walk->nbytes = walk->total;
280	if (unlikely(!walk->total))
281	return 0;
282
283	walk->iv_buffer = NULL;
284	walk->iv = req->info;
285	if (unlikely(((unsigned long)walk->iv & alignmask))) {
286	int err = ablkcipher_copy_iv(walk, tfm, alignmask);
287	if (err)
288	return err;
289	}
290
291	scatterwalk_start(&walk->in, walk->in.sg);
292	scatterwalk_start(&walk->out, walk->out.sg);
293
294	return ablkcipher_walk_next(req, walk);
295	}
296
297	int ablkcipher_walk_phys(struct ablkcipher_request *req,
298	struct ablkcipher_walk *walk)
299	{
300	walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
301	return ablkcipher_walk_first(req, walk);
302	}
303	EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
304
791b4d5f HX	305	static int setkey_unaligned(struct crypto_ablkcipher tfm, const u8 key,
791b4d5f HX	306	unsigned int keylen)
ca7c3938 SS	307	{
	308	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	309	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
	310	int ret;
	311	u8 buffer, alignbuffer;
	312	unsigned long absize;
	313
	314	absize = keylen + alignmask;
	315	buffer = kmalloc(absize, GFP_ATOMIC);
	316	if (!buffer)
	317	return -ENOMEM;
	318
	319	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	320	memcpy(alignbuffer, key, keylen);
	321	ret = cipher->setkey(tfm, alignbuffer, keylen);
06817176	322	memset(alignbuffer, 0, keylen);
ca7c3938 SS	323	kfree(buffer);
	324	return ret;
	325	}
	326
b5b7f088 HX	327	static int setkey(struct crypto_ablkcipher tfm, const u8 key,
	328	unsigned int keylen)
	329	{
	330	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
ca7c3938	331	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
b5b7f088 HX	332
	333	if (keylen < cipher->min_keysize \|\| keylen > cipher->max_keysize) {
	334	crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	335	return -EINVAL;
	336	}
	337
ca7c3938 SS	338	if ((unsigned long)key & alignmask)
	339	return setkey_unaligned(tfm, key, keylen);
	340
b5b7f088 HX	341	return cipher->setkey(tfm, key, keylen);
	342	}
	343
	344	static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
	345	u32 mask)
	346	{
	347	return alg->cra_ctxsize;
	348	}
	349
b9c55aa4 HX	350	int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
	351	{
	352	return crypto_ablkcipher_encrypt(&req->creq);
	353	}
	354
	355	int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
	356	{
	357	return crypto_ablkcipher_decrypt(&req->creq);
	358	}
	359
b5b7f088 HX	360	static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
	361	u32 mask)
	362	{
	363	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	364	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	365
	366	if (alg->ivsize > PAGE_SIZE / 8)
	367	return -EINVAL;
	368
	369	crt->setkey = setkey;
	370	crt->encrypt = alg->encrypt;
	371	crt->decrypt = alg->decrypt;
b9c55aa4 HX	372	if (!alg->ivsize) {
	373	crt->givencrypt = skcipher_null_givencrypt;
	374	crt->givdecrypt = skcipher_null_givdecrypt;
	375	}
ecfc4329	376	crt->base = __crypto_ablkcipher_cast(tfm);
b5b7f088 HX	377	crt->ivsize = alg->ivsize;
	378
	379	return 0;
	380	}
	381
3acc8473	382	#ifdef CONFIG_NET
29ffc876 SK	383	static int crypto_ablkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	384	{
	385	struct crypto_report_blkcipher rblkcipher;
	386
9a5467bf MK	387	strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
	388	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
	389	sizeof(rblkcipher.geniv));
29ffc876 SK	390
	391	rblkcipher.blocksize = alg->cra_blocksize;
	392	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
	393	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
	394	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
	395
6662df33 DM	396	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	397	sizeof(struct crypto_report_blkcipher), &rblkcipher))
	398	goto nla_put_failure;
29ffc876 SK	399	return 0;
	400
	401	nla_put_failure:
	402	return -EMSGSIZE;
	403	}
3acc8473 HX	404	#else
	405	static int crypto_ablkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	406	{
	407	return -ENOSYS;
	408	}
	409	#endif
29ffc876	410
b5b7f088 HX	411	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	412	__attribute__ ((unused));
	413	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	414	{
	415	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	416
	417	seq_printf(m, "type : ablkcipher\n");
189ed66e HX	418	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
189ed66e HX	419	"yes" : "no");
b5b7f088 HX	420	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	421	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	422	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	423	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	424	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
b5b7f088 HX	425	}
	426
	427	const struct crypto_type crypto_ablkcipher_type = {
	428	.ctxsize = crypto_ablkcipher_ctxsize,
	429	.init = crypto_init_ablkcipher_ops,
	430	#ifdef CONFIG_PROC_FS
	431	.show = crypto_ablkcipher_show,
	432	#endif
29ffc876	433	.report = crypto_ablkcipher_report,
b5b7f088 HX	434	};
	435	EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
	436
61da88e2 HX	437	static int no_givdecrypt(struct skcipher_givcrypt_request *req)
	438	{
	439	return -ENOSYS;
	440	}
	441
	442	static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
	443	u32 mask)
	444	{
	445	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	446	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	447
	448	if (alg->ivsize > PAGE_SIZE / 8)
	449	return -EINVAL;
	450
ecfc4329 HX	451	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
ecfc4329 HX	452	alg->setkey : setkey;
61da88e2 HX	453	crt->encrypt = alg->encrypt;
	454	crt->decrypt = alg->decrypt;
	455	crt->givencrypt = alg->givencrypt;
	456	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
ecfc4329	457	crt->base = __crypto_ablkcipher_cast(tfm);
61da88e2 HX	458	crt->ivsize = alg->ivsize;
	459
	460	return 0;
	461	}
	462
3acc8473	463	#ifdef CONFIG_NET
3e29c109 SK	464	static int crypto_givcipher_report(struct sk_buff skb, struct crypto_alg alg)
	465	{
	466	struct crypto_report_blkcipher rblkcipher;
	467
9a5467bf MK	468	strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
	469	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
	470	sizeof(rblkcipher.geniv));
3e29c109 SK	471
	472	rblkcipher.blocksize = alg->cra_blocksize;
	473	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
	474	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
	475	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
	476
6662df33 DM	477	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	478	sizeof(struct crypto_report_blkcipher), &rblkcipher))
	479	goto nla_put_failure;
3e29c109 SK	480	return 0;
	481
	482	nla_put_failure:
	483	return -EMSGSIZE;
	484	}
3acc8473 HX	485	#else
	486	static int crypto_givcipher_report(struct sk_buff skb, struct crypto_alg alg)
	487	{
	488	return -ENOSYS;
	489	}
	490	#endif
3e29c109	491
61da88e2 HX	492	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	493	__attribute__ ((unused));
	494	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	495	{
	496	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	497
	498	seq_printf(m, "type : givcipher\n");
189ed66e HX	499	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
189ed66e HX	500	"yes" : "no");
61da88e2 HX	501	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	502	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	503	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	504	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	505	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
61da88e2 HX	506	}
	507
	508	const struct crypto_type crypto_givcipher_type = {
	509	.ctxsize = crypto_ablkcipher_ctxsize,
	510	.init = crypto_init_givcipher_ops,
	511	#ifdef CONFIG_PROC_FS
	512	.show = crypto_givcipher_show,
	513	#endif
3e29c109	514	.report = crypto_givcipher_report,
61da88e2 HX	515	};
	516	EXPORT_SYMBOL_GPL(crypto_givcipher_type);
	517
ecfc4329 HX	518	const char crypto_default_geniv(const struct crypto_alg alg)
ecfc4329 HX	519	{
63b5ac28 HX	520	if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	521	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	522	alg->cra_ablkcipher.ivsize) !=
	523	alg->cra_blocksize)
	524	return "chainiv";
	525
f3d53ed0	526	return "eseqiv";
ecfc4329 HX	527	}
ecfc4329 HX	528
b9c55aa4 HX	529	static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
	530	{
	531	struct rtattr *tb[3];
	532	struct {
	533	struct rtattr attr;
	534	struct crypto_attr_type data;
	535	} ptype;
	536	struct {
	537	struct rtattr attr;
	538	struct crypto_attr_alg data;
	539	} palg;
	540	struct crypto_template *tmpl;
	541	struct crypto_instance *inst;
	542	struct crypto_alg *larval;
	543	const char *geniv;
	544	int err;
	545
	546	larval = crypto_larval_lookup(alg->cra_driver_name,
435578ae	547	(type & ~CRYPTO_ALG_TYPE_MASK) \|
b9c55aa4	548	CRYPTO_ALG_TYPE_GIVCIPHER,
435578ae	549	mask \| CRYPTO_ALG_TYPE_MASK);
b9c55aa4 HX	550	err = PTR_ERR(larval);
	551	if (IS_ERR(larval))
	552	goto out;
	553
	554	err = -EAGAIN;
	555	if (!crypto_is_larval(larval))
	556	goto drop_larval;
	557
	558	ptype.attr.rta_len = sizeof(ptype);
	559	ptype.attr.rta_type = CRYPTOA_TYPE;
	560	ptype.data.type = type \| CRYPTO_ALG_GENIV;
	561	/* GENIV tells the template that we're making a default geniv. */
	562	ptype.data.mask = mask \| CRYPTO_ALG_GENIV;
	563	tb[0] = &ptype.attr;
	564
	565	palg.attr.rta_len = sizeof(palg);
	566	palg.attr.rta_type = CRYPTOA_ALG;
	567	/* Must use the exact name to locate ourselves. */
	568	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
	569	tb[1] = &palg.attr;
	570
	571	tb[2] = NULL;
	572
	573	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	574	CRYPTO_ALG_TYPE_BLKCIPHER)
	575	geniv = alg->cra_blkcipher.geniv;
	576	else
	577	geniv = alg->cra_ablkcipher.geniv;
	578
	579	if (!geniv)
	580	geniv = crypto_default_geniv(alg);
	581
	582	tmpl = crypto_lookup_template(geniv);
	583	err = -ENOENT;
	584	if (!tmpl)
	585	goto kill_larval;
	586
	587	inst = tmpl->alloc(tb);
	588	err = PTR_ERR(inst);
	589	if (IS_ERR(inst))
	590	goto put_tmpl;
	591
	592	if ((err = crypto_register_instance(tmpl, inst))) {
	593	tmpl->free(inst);
	594	goto put_tmpl;
	595	}
	596
	597	/* Redo the lookup to use the instance we just registered. */
	598	err = -EAGAIN;
	599
	600	put_tmpl:
	601	crypto_tmpl_put(tmpl);
	602	kill_larval:
	603	crypto_larval_kill(larval);
	604	drop_larval:
	605	crypto_mod_put(larval);
	606	out:
	607	crypto_mod_put(alg);
	608	return err;
	609	}
	610
1e122994	611	struct crypto_alg crypto_lookup_skcipher(const char name, u32 type, u32 mask)
b9c55aa4 HX	612	{
	613	struct crypto_alg *alg;
	614
	615	alg = crypto_alg_mod_lookup(name, type, mask);
	616	if (IS_ERR(alg))
	617	return alg;
	618
	619	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	620	CRYPTO_ALG_TYPE_GIVCIPHER)
	621	return alg;
	622
	623	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	624	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	625	alg->cra_ablkcipher.ivsize))
	626	return alg;
	627
b170a137 HX	628	crypto_mod_put(alg);
	629	alg = crypto_alg_mod_lookup(name, type \| CRYPTO_ALG_TESTED,
	630	mask & ~CRYPTO_ALG_TESTED);
	631	if (IS_ERR(alg))
	632	return alg;
	633
	634	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	635	CRYPTO_ALG_TYPE_GIVCIPHER) {
	636	if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
	637	crypto_mod_put(alg);
	638	alg = ERR_PTR(-ENOENT);
	639	}
	640	return alg;
	641	}
	642
	643	BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	644	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	645	alg->cra_ablkcipher.ivsize));
	646
b9c55aa4 HX	647	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
b9c55aa4 HX	648	}
1e122994	649	EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);
b9c55aa4	650
378f4f51 HX	651	int crypto_grab_skcipher(struct crypto_skcipher_spawn spawn, const char name,
	652	u32 type, u32 mask)
	653	{
	654	struct crypto_alg *alg;
	655	int err;
	656
	657	type = crypto_skcipher_type(type);
	658	mask = crypto_skcipher_mask(mask);
	659
b9c55aa4	660	alg = crypto_lookup_skcipher(name, type, mask);
378f4f51 HX	661	if (IS_ERR(alg))
	662	return PTR_ERR(alg);
	663
	664	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
	665	crypto_mod_put(alg);
	666	return err;
	667	}
	668	EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
	669
b9c55aa4 HX	670	struct crypto_ablkcipher crypto_alloc_ablkcipher(const char alg_name,
	671	u32 type, u32 mask)
	672	{
	673	struct crypto_tfm *tfm;
	674	int err;
	675
	676	type = crypto_skcipher_type(type);
	677	mask = crypto_skcipher_mask(mask);
	678
	679	for (;;) {
	680	struct crypto_alg *alg;
	681
	682	alg = crypto_lookup_skcipher(alg_name, type, mask);
	683	if (IS_ERR(alg)) {
	684	err = PTR_ERR(alg);
	685	goto err;
	686	}
	687
	688	tfm = __crypto_alloc_tfm(alg, type, mask);
	689	if (!IS_ERR(tfm))
	690	return __crypto_ablkcipher_cast(tfm);
	691
	692	crypto_mod_put(alg);
	693	err = PTR_ERR(tfm);
	694
	695	err:
	696	if (err != -EAGAIN)
	697	break;
	698	if (signal_pending(current)) {
	699	err = -EINTR;
	700	break;
	701	}
	702	}
	703
	704	return ERR_PTR(err);
	705	}
	706	EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);