[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/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, 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 ?: no_givdecrypt;
	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;

	if (tmpl->create) {
		err = tmpl->create(tmpl, tb);
		if (err)
			goto put_tmpl;
		goto ok;
	}

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

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

ok:
	/* 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 (fatal_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 <[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>
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);
a861afbc	72
bf06099d DM	73	return max(start, end_page);
	74	}
	75
	76	static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
	77	unsigned int bsize)
	78	{
	79	unsigned int n = bsize;
	80
	81	for (;;) {
	82	unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
	83
	84	if (len_this_page > n)
	85	len_this_page = n;
	86	scatterwalk_advance(&walk->out, n);
	87	if (n == len_this_page)
	88	break;
	89	n -= len_this_page;
5be4d4c9	90	scatterwalk_start(&walk->out, sg_next(walk->out.sg));
bf06099d DM	91	}
	92
	93	return bsize;
	94	}
	95
	96	static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
	97	unsigned int n)
	98	{
	99	scatterwalk_advance(&walk->in, n);
	100	scatterwalk_advance(&walk->out, n);
	101
	102	return n;
	103	}
	104
	105	static int ablkcipher_walk_next(struct ablkcipher_request *req,
	106	struct ablkcipher_walk *walk);
	107
	108	int ablkcipher_walk_done(struct ablkcipher_request *req,
	109	struct ablkcipher_walk *walk, int err)
	110	{
	111	struct crypto_tfm *tfm = req->base.tfm;
	112	unsigned int nbytes = 0;
	113
	114	if (likely(err >= 0)) {
	115	unsigned int n = walk->nbytes - err;
	116
	117	if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
	118	n = ablkcipher_done_fast(walk, n);
	119	else if (WARN_ON(err)) {
	120	err = -EINVAL;
	121	goto err;
	122	} else
	123	n = ablkcipher_done_slow(walk, n);
	124
	125	nbytes = walk->total - n;
	126	err = 0;
	127	}
	128
	129	scatterwalk_done(&walk->in, 0, nbytes);
	130	scatterwalk_done(&walk->out, 1, nbytes);
	131
	132	err:
	133	walk->total = nbytes;
	134	walk->nbytes = nbytes;
	135
	136	if (nbytes) {
	137	crypto_yield(req->base.flags);
	138	return ablkcipher_walk_next(req, walk);
	139	}
	140
	141	if (walk->iv != req->info)
	142	memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
33c7c0fb	143	kfree(walk->iv_buffer);
bf06099d DM	144
	145	return err;
	146	}
	147	EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
	148
	149	static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
	150	struct ablkcipher_walk *walk,
	151	unsigned int bsize,
	152	unsigned int alignmask,
	153	void src_p, void dst_p)
	154	{
	155	unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
	156	struct ablkcipher_buffer *p;
	157	void src, dst, *base;
	158	unsigned int n;
	159
	160	n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
	161	n += (aligned_bsize * 3 - (alignmask + 1) +
	162	(alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
	163
	164	p = kmalloc(n, GFP_ATOMIC);
	165	if (!p)
2716fbf6	166	return ablkcipher_walk_done(req, walk, -ENOMEM);
bf06099d DM	167
	168	base = p + 1;
	169
	170	dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
	171	src = dst = ablkcipher_get_spot(dst, bsize);
	172
	173	p->len = bsize;
	174	p->data = dst;
	175
	176	scatterwalk_copychunks(src, &walk->in, bsize, 0);
	177
	178	ablkcipher_queue_write(walk, p);
	179
	180	walk->nbytes = bsize;
	181	walk->flags \|= ABLKCIPHER_WALK_SLOW;
	182
	183	*src_p = src;
	184	*dst_p = dst;
	185
	186	return 0;
	187	}
	188
	189	static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
	190	struct crypto_tfm *tfm,
	191	unsigned int alignmask)
	192	{
	193	unsigned bs = walk->blocksize;
	194	unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
	195	unsigned aligned_bs = ALIGN(bs, alignmask + 1);
	196	unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
	197	(alignmask + 1);
	198	u8 *iv;
	199
	200	size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
	201	walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
	202	if (!walk->iv_buffer)
	203	return -ENOMEM;
	204
	205	iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
	206	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
	207	iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
	208	iv = ablkcipher_get_spot(iv, ivsize);
	209
	210	walk->iv = memcpy(iv, walk->iv, ivsize);
	211	return 0;
	212	}
	213
	214	static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
	215	struct ablkcipher_walk *walk)
	216	{
	217	walk->src.page = scatterwalk_page(&walk->in);
	218	walk->src.offset = offset_in_page(walk->in.offset);
	219	walk->dst.page = scatterwalk_page(&walk->out);
	220	walk->dst.offset = offset_in_page(walk->out.offset);
	221
	222	return 0;
	223	}
	224
	225	static int ablkcipher_walk_next(struct ablkcipher_request *req,
	226	struct ablkcipher_walk *walk)
	227	{
	228	struct crypto_tfm *tfm = req->base.tfm;
	229	unsigned int alignmask, bsize, n;
	230	void src, dst;
231	int err;
232
233	alignmask = crypto_tfm_alg_alignmask(tfm);
234	n = walk->total;
235	if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
236	req->base.flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
237	return ablkcipher_walk_done(req, walk, -EINVAL);
238	}
239
240	walk->flags &= ~ABLKCIPHER_WALK_SLOW;
241	src = dst = NULL;
242
243	bsize = min(walk->blocksize, n);
244	n = scatterwalk_clamp(&walk->in, n);
245	n = scatterwalk_clamp(&walk->out, n);
246
247	if (n < bsize \|\|
248	!scatterwalk_aligned(&walk->in, alignmask) \|\|
249	!scatterwalk_aligned(&walk->out, alignmask)) {
250	err = ablkcipher_next_slow(req, walk, bsize, alignmask,
251	&src, &dst);
252	goto set_phys_lowmem;
253	}
254
255	walk->nbytes = n;
256
257	return ablkcipher_next_fast(req, walk);
258
259	set_phys_lowmem:
260	if (err >= 0) {
261	walk->src.page = virt_to_page(src);
262	walk->dst.page = virt_to_page(dst);
263	walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
264	walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
265	}
266
267	return err;
268	}
269
270	static int ablkcipher_walk_first(struct ablkcipher_request *req,
271	struct ablkcipher_walk *walk)
272	{
273	struct crypto_tfm *tfm = req->base.tfm;
274	unsigned int alignmask;
275
276	alignmask = crypto_tfm_alg_alignmask(tfm);
277	if (WARN_ON_ONCE(in_irq()))
278	return -EDEADLK;
279
280	walk->nbytes = walk->total;
281	if (unlikely(!walk->total))
282	return 0;
283
284	walk->iv_buffer = NULL;
285	walk->iv = req->info;
286	if (unlikely(((unsigned long)walk->iv & alignmask))) {
287	int err = ablkcipher_copy_iv(walk, tfm, alignmask);
a861afbc	288
bf06099d DM	289	if (err)
	290	return err;
	291	}
	292
	293	scatterwalk_start(&walk->in, walk->in.sg);
	294	scatterwalk_start(&walk->out, walk->out.sg);
	295
	296	return ablkcipher_walk_next(req, walk);
	297	}
	298
	299	int ablkcipher_walk_phys(struct ablkcipher_request *req,
	300	struct ablkcipher_walk *walk)
	301	{
	302	walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
	303	return ablkcipher_walk_first(req, walk);
	304	}
	305	EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
	306
791b4d5f HX	307	static int setkey_unaligned(struct crypto_ablkcipher tfm, const u8 key,
791b4d5f HX	308	unsigned int keylen)
ca7c3938 SS	309	{
	310	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
	311	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
	312	int ret;
	313	u8 buffer, alignbuffer;
	314	unsigned long absize;
	315
	316	absize = keylen + alignmask;
	317	buffer = kmalloc(absize, GFP_ATOMIC);
	318	if (!buffer)
	319	return -ENOMEM;
	320
	321	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	322	memcpy(alignbuffer, key, keylen);
	323	ret = cipher->setkey(tfm, alignbuffer, keylen);
06817176	324	memset(alignbuffer, 0, keylen);
ca7c3938 SS	325	kfree(buffer);
	326	return ret;
	327	}
	328
b5b7f088 HX	329	static int setkey(struct crypto_ablkcipher tfm, const u8 key,
	330	unsigned int keylen)
	331	{
	332	struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
ca7c3938	333	unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
b5b7f088 HX	334
	335	if (keylen < cipher->min_keysize \|\| keylen > cipher->max_keysize) {
	336	crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	337	return -EINVAL;
	338	}
	339
ca7c3938 SS	340	if ((unsigned long)key & alignmask)
	341	return setkey_unaligned(tfm, key, keylen);
	342
b5b7f088 HX	343	return cipher->setkey(tfm, key, keylen);
	344	}
	345
	346	static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
	347	u32 mask)
	348	{
	349	return alg->cra_ctxsize;
	350	}
	351
b9c55aa4 HX	352	int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
	353	{
	354	return crypto_ablkcipher_encrypt(&req->creq);
	355	}
	356
	357	int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
	358	{
	359	return crypto_ablkcipher_decrypt(&req->creq);
	360	}
	361
b5b7f088 HX	362	static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
	363	u32 mask)
	364	{
	365	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	366	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	367
	368	if (alg->ivsize > PAGE_SIZE / 8)
	369	return -EINVAL;
	370
	371	crt->setkey = setkey;
	372	crt->encrypt = alg->encrypt;
	373	crt->decrypt = alg->decrypt;
b9c55aa4 HX	374	if (!alg->ivsize) {
	375	crt->givencrypt = skcipher_null_givencrypt;
	376	crt->givdecrypt = skcipher_null_givdecrypt;
	377	}
ecfc4329	378	crt->base = __crypto_ablkcipher_cast(tfm);
b5b7f088 HX	379	crt->ivsize = alg->ivsize;
	380
	381	return 0;
	382	}
	383
3acc8473	384	#ifdef CONFIG_NET
29ffc876 SK	385	static int crypto_ablkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	386	{
	387	struct crypto_report_blkcipher rblkcipher;
	388
9a5467bf MK	389	strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
	390	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
	391	sizeof(rblkcipher.geniv));
29ffc876 SK	392
	393	rblkcipher.blocksize = alg->cra_blocksize;
	394	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
	395	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
	396	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
	397
6662df33 DM	398	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	399	sizeof(struct crypto_report_blkcipher), &rblkcipher))
	400	goto nla_put_failure;
29ffc876 SK	401	return 0;
	402
	403	nla_put_failure:
	404	return -EMSGSIZE;
	405	}
3acc8473 HX	406	#else
	407	static int crypto_ablkcipher_report(struct sk_buff skb, struct crypto_alg alg)
	408	{
	409	return -ENOSYS;
	410	}
	411	#endif
29ffc876	412
b5b7f088 HX	413	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	414	__attribute__ ((unused));
	415	static void crypto_ablkcipher_show(struct seq_file m, struct crypto_alg alg)
	416	{
	417	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	418
	419	seq_printf(m, "type : ablkcipher\n");
189ed66e HX	420	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
189ed66e HX	421	"yes" : "no");
b5b7f088 HX	422	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	423	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	424	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	425	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	426	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
b5b7f088 HX	427	}
	428
	429	const struct crypto_type crypto_ablkcipher_type = {
	430	.ctxsize = crypto_ablkcipher_ctxsize,
	431	.init = crypto_init_ablkcipher_ops,
	432	#ifdef CONFIG_PROC_FS
	433	.show = crypto_ablkcipher_show,
	434	#endif
29ffc876	435	.report = crypto_ablkcipher_report,
b5b7f088 HX	436	};
	437	EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
	438
61da88e2 HX	439	static int no_givdecrypt(struct skcipher_givcrypt_request *req)
	440	{
	441	return -ENOSYS;
	442	}
	443
	444	static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
	445	u32 mask)
	446	{
	447	struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
	448	struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
	449
	450	if (alg->ivsize > PAGE_SIZE / 8)
	451	return -EINVAL;
	452
ecfc4329 HX	453	crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
ecfc4329 HX	454	alg->setkey : setkey;
61da88e2 HX	455	crt->encrypt = alg->encrypt;
61da88e2 HX	456	crt->decrypt = alg->decrypt;
21dbd96f	457	crt->givencrypt = alg->givencrypt ?: no_givdecrypt;
61da88e2	458	crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
ecfc4329	459	crt->base = __crypto_ablkcipher_cast(tfm);
61da88e2 HX	460	crt->ivsize = alg->ivsize;
	461
	462	return 0;
	463	}
	464
3acc8473	465	#ifdef CONFIG_NET
3e29c109 SK	466	static int crypto_givcipher_report(struct sk_buff skb, struct crypto_alg alg)
	467	{
	468	struct crypto_report_blkcipher rblkcipher;
	469
9a5467bf MK	470	strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
	471	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
	472	sizeof(rblkcipher.geniv));
3e29c109 SK	473
	474	rblkcipher.blocksize = alg->cra_blocksize;
	475	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
	476	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
	477	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
	478
6662df33 DM	479	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
	480	sizeof(struct crypto_report_blkcipher), &rblkcipher))
	481	goto nla_put_failure;
3e29c109 SK	482	return 0;
	483
	484	nla_put_failure:
	485	return -EMSGSIZE;
	486	}
3acc8473 HX	487	#else
	488	static int crypto_givcipher_report(struct sk_buff skb, struct crypto_alg alg)
	489	{
	490	return -ENOSYS;
	491	}
	492	#endif
3e29c109	493
61da88e2 HX	494	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	495	__attribute__ ((unused));
	496	static void crypto_givcipher_show(struct seq_file m, struct crypto_alg alg)
	497	{
	498	struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
	499
	500	seq_printf(m, "type : givcipher\n");
189ed66e HX	501	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
189ed66e HX	502	"yes" : "no");
61da88e2 HX	503	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
	504	seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
	505	seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
	506	seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
23508e11	507	seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
61da88e2 HX	508	}
	509
	510	const struct crypto_type crypto_givcipher_type = {
	511	.ctxsize = crypto_ablkcipher_ctxsize,
	512	.init = crypto_init_givcipher_ops,
	513	#ifdef CONFIG_PROC_FS
	514	.show = crypto_givcipher_show,
	515	#endif
3e29c109	516	.report = crypto_givcipher_report,
61da88e2 HX	517	};
	518	EXPORT_SYMBOL_GPL(crypto_givcipher_type);
	519
ecfc4329 HX	520	const char crypto_default_geniv(const struct crypto_alg alg)
ecfc4329 HX	521	{
63b5ac28 HX	522	if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	523	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	524	alg->cra_ablkcipher.ivsize) !=
	525	alg->cra_blocksize)
	526	return "chainiv";
	527
f3d53ed0	528	return "eseqiv";
ecfc4329 HX	529	}
ecfc4329 HX	530
b9c55aa4 HX	531	static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
	532	{
	533	struct rtattr *tb[3];
	534	struct {
	535	struct rtattr attr;
	536	struct crypto_attr_type data;
	537	} ptype;
	538	struct {
	539	struct rtattr attr;
	540	struct crypto_attr_alg data;
	541	} palg;
	542	struct crypto_template *tmpl;
	543	struct crypto_instance *inst;
	544	struct crypto_alg *larval;
	545	const char *geniv;
	546	int err;
	547
	548	larval = crypto_larval_lookup(alg->cra_driver_name,
435578ae	549	(type & ~CRYPTO_ALG_TYPE_MASK) \|
b9c55aa4	550	CRYPTO_ALG_TYPE_GIVCIPHER,
435578ae	551	mask \| CRYPTO_ALG_TYPE_MASK);
b9c55aa4 HX	552	err = PTR_ERR(larval);
	553	if (IS_ERR(larval))
	554	goto out;
	555
	556	err = -EAGAIN;
	557	if (!crypto_is_larval(larval))
	558	goto drop_larval;
	559
	560	ptype.attr.rta_len = sizeof(ptype);
	561	ptype.attr.rta_type = CRYPTOA_TYPE;
	562	ptype.data.type = type \| CRYPTO_ALG_GENIV;
	563	/* GENIV tells the template that we're making a default geniv. */
	564	ptype.data.mask = mask \| CRYPTO_ALG_GENIV;
	565	tb[0] = &ptype.attr;
	566
	567	palg.attr.rta_len = sizeof(palg);
	568	palg.attr.rta_type = CRYPTOA_ALG;
	569	/* Must use the exact name to locate ourselves. */
	570	memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
	571	tb[1] = &palg.attr;
	572
	573	tb[2] = NULL;
	574
	575	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	576	CRYPTO_ALG_TYPE_BLKCIPHER)
	577	geniv = alg->cra_blkcipher.geniv;
	578	else
	579	geniv = alg->cra_ablkcipher.geniv;
	580
	581	if (!geniv)
	582	geniv = crypto_default_geniv(alg);
	583
	584	tmpl = crypto_lookup_template(geniv);
	585	err = -ENOENT;
	586	if (!tmpl)
	587	goto kill_larval;
	588
56e34378 HX	589	if (tmpl->create) {
	590	err = tmpl->create(tmpl, tb);
	591	if (err)
	592	goto put_tmpl;
	593	goto ok;
	594	}
	595
b9c55aa4 HX	596	inst = tmpl->alloc(tb);
	597	err = PTR_ERR(inst);
	598	if (IS_ERR(inst))
	599	goto put_tmpl;
	600
a861afbc JJ	601	err = crypto_register_instance(tmpl, inst);
a861afbc JJ	602	if (err) {
b9c55aa4 HX	603	tmpl->free(inst);
	604	goto put_tmpl;
	605	}
	606
56e34378	607	ok:
b9c55aa4 HX	608	/* Redo the lookup to use the instance we just registered. */
	609	err = -EAGAIN;
	610
	611	put_tmpl:
	612	crypto_tmpl_put(tmpl);
	613	kill_larval:
	614	crypto_larval_kill(larval);
	615	drop_larval:
	616	crypto_mod_put(larval);
	617	out:
	618	crypto_mod_put(alg);
	619	return err;
	620	}
	621
1e122994	622	struct crypto_alg crypto_lookup_skcipher(const char name, u32 type, u32 mask)
b9c55aa4 HX	623	{
	624	struct crypto_alg *alg;
	625
	626	alg = crypto_alg_mod_lookup(name, type, mask);
	627	if (IS_ERR(alg))
	628	return alg;
	629
	630	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	631	CRYPTO_ALG_TYPE_GIVCIPHER)
	632	return alg;
	633
	634	if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	635	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	636	alg->cra_ablkcipher.ivsize))
	637	return alg;
	638
b170a137 HX	639	crypto_mod_put(alg);
	640	alg = crypto_alg_mod_lookup(name, type \| CRYPTO_ALG_TESTED,
	641	mask & ~CRYPTO_ALG_TESTED);
	642	if (IS_ERR(alg))
	643	return alg;
	644
	645	if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	646	CRYPTO_ALG_TYPE_GIVCIPHER) {
26739535	647	if (~alg->cra_flags & (type ^ ~mask) & CRYPTO_ALG_TESTED) {
b170a137 HX	648	crypto_mod_put(alg);
	649	alg = ERR_PTR(-ENOENT);
	650	}
	651	return alg;
	652	}
	653
	654	BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
	655	CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
	656	alg->cra_ablkcipher.ivsize));
	657
b9c55aa4 HX	658	return ERR_PTR(crypto_givcipher_default(alg, type, mask));
b9c55aa4 HX	659	}
1e122994	660	EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);
b9c55aa4	661
378f4f51 HX	662	int crypto_grab_skcipher(struct crypto_skcipher_spawn spawn, const char name,
	663	u32 type, u32 mask)
	664	{
	665	struct crypto_alg *alg;
	666	int err;
	667
	668	type = crypto_skcipher_type(type);
	669	mask = crypto_skcipher_mask(mask);
	670
b9c55aa4	671	alg = crypto_lookup_skcipher(name, type, mask);
378f4f51 HX	672	if (IS_ERR(alg))
	673	return PTR_ERR(alg);
	674
	675	err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
	676	crypto_mod_put(alg);
	677	return err;
	678	}
	679	EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
	680
b9c55aa4 HX	681	struct crypto_ablkcipher crypto_alloc_ablkcipher(const char alg_name,
	682	u32 type, u32 mask)
	683	{
	684	struct crypto_tfm *tfm;
	685	int err;
	686
	687	type = crypto_skcipher_type(type);
	688	mask = crypto_skcipher_mask(mask);
	689
	690	for (;;) {
	691	struct crypto_alg *alg;
	692
	693	alg = crypto_lookup_skcipher(alg_name, type, mask);
	694	if (IS_ERR(alg)) {
	695	err = PTR_ERR(alg);
	696	goto err;
	697	}
	698
	699	tfm = __crypto_alloc_tfm(alg, type, mask);
	700	if (!IS_ERR(tfm))
	701	return __crypto_ablkcipher_cast(tfm);
	702
	703	crypto_mod_put(alg);
	704	err = PTR_ERR(tfm);
	705
	706	err:
	707	if (err != -EAGAIN)
	708	break;
3fc89adb	709	if (fatal_signal_pending(current)) {
b9c55aa4 HX	710	err = -EINTR;
	711	break;
	712	}
	713	}
	714
	715	return ERR_PTR(err);
	716	}
	717	EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);