linux/crypto/digest.c
Herbert Xu b2ab4a57b0 [CRYPTO] scatterwalk: Restore custom sg chaining for now
Unfortunately the generic chaining hasn't been ported to all architectures
yet, and notably not s390.  So this patch restores the chainging that we've
been using previously which does work everywhere.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:33 +11:00

157 lines
3.7 KiB
C

/*
* Cryptographic API.
*
* Digest operations.
*
* Copyright (c) 2002 James Morris <jmorris@intercode.com.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/scatterwalk.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/hardirq.h>
#include <linux/highmem.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
static int init(struct hash_desc *desc)
{
struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
tfm->__crt_alg->cra_digest.dia_init(tfm);
return 0;
}
static int update2(struct hash_desc *desc,
struct scatterlist *sg, unsigned int nbytes)
{
struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
if (!nbytes)
return 0;
for (;;) {
struct page *pg = sg_page(sg);
unsigned int offset = sg->offset;
unsigned int l = sg->length;
if (unlikely(l > nbytes))
l = nbytes;
nbytes -= l;
do {
unsigned int bytes_from_page = min(l, ((unsigned int)
(PAGE_SIZE)) -
offset);
char *src = crypto_kmap(pg, 0);
char *p = src + offset;
if (unlikely(offset & alignmask)) {
unsigned int bytes =
alignmask + 1 - (offset & alignmask);
bytes = min(bytes, bytes_from_page);
tfm->__crt_alg->cra_digest.dia_update(tfm, p,
bytes);
p += bytes;
bytes_from_page -= bytes;
l -= bytes;
}
tfm->__crt_alg->cra_digest.dia_update(tfm, p,
bytes_from_page);
crypto_kunmap(src, 0);
crypto_yield(desc->flags);
offset = 0;
pg++;
l -= bytes_from_page;
} while (l > 0);
if (!nbytes)
break;
sg = scatterwalk_sg_next(sg);
}
return 0;
}
static int update(struct hash_desc *desc,
struct scatterlist *sg, unsigned int nbytes)
{
if (WARN_ON_ONCE(in_irq()))
return -EDEADLK;
return update2(desc, sg, nbytes);
}
static int final(struct hash_desc *desc, u8 *out)
{
struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
struct digest_alg *digest = &tfm->__crt_alg->cra_digest;
if (unlikely((unsigned long)out & alignmask)) {
unsigned long align = alignmask + 1;
unsigned long addr = (unsigned long)crypto_tfm_ctx(tfm);
u8 *dst = (u8 *)ALIGN(addr, align) +
ALIGN(tfm->__crt_alg->cra_ctxsize, align);
digest->dia_final(tfm, dst);
memcpy(out, dst, digest->dia_digestsize);
} else
digest->dia_final(tfm, out);
return 0;
}
static int nosetkey(struct crypto_hash *tfm, const u8 *key, unsigned int keylen)
{
crypto_hash_clear_flags(tfm, CRYPTO_TFM_RES_MASK);
return -ENOSYS;
}
static int setkey(struct crypto_hash *hash, const u8 *key, unsigned int keylen)
{
struct crypto_tfm *tfm = crypto_hash_tfm(hash);
crypto_hash_clear_flags(hash, CRYPTO_TFM_RES_MASK);
return tfm->__crt_alg->cra_digest.dia_setkey(tfm, key, keylen);
}
static int digest(struct hash_desc *desc,
struct scatterlist *sg, unsigned int nbytes, u8 *out)
{
if (WARN_ON_ONCE(in_irq()))
return -EDEADLK;
init(desc);
update2(desc, sg, nbytes);
return final(desc, out);
}
int crypto_init_digest_ops(struct crypto_tfm *tfm)
{
struct hash_tfm *ops = &tfm->crt_hash;
struct digest_alg *dalg = &tfm->__crt_alg->cra_digest;
if (dalg->dia_digestsize > crypto_tfm_alg_blocksize(tfm))
return -EINVAL;
ops->init = init;
ops->update = update;
ops->final = final;
ops->digest = digest;
ops->setkey = dalg->dia_setkey ? setkey : nosetkey;
ops->digestsize = dalg->dia_digestsize;
return 0;
}
void crypto_exit_digest_ops(struct crypto_tfm *tfm)
{
}