linux/arch/s390/crypto/sha_common.c
YueHaibing 0398d4ab16 s390/crypto: Fix unsigned variable compared with zero
s390_crypto_shash_parmsize() return type is int, it
should not be stored in a unsigned variable, which
compared with zero.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 3c2eb6b76c ("s390/crypto: Support for SHA3 via CPACF (MSA6)")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Joerg Schmidbauer <jschmidb@linux.vnet.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-11-20 12:58:12 +01:00

125 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Cryptographic API.
*
* s390 generic implementation of the SHA Secure Hash Algorithms.
*
* Copyright IBM Corp. 2007
* Author(s): Jan Glauber (jang@de.ibm.com)
*/
#include <crypto/internal/hash.h>
#include <linux/module.h>
#include <asm/cpacf.h>
#include "sha.h"
int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len)
{
struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
unsigned int bsize = crypto_shash_blocksize(desc->tfm);
unsigned int index, n;
/* how much is already in the buffer? */
index = ctx->count % bsize;
ctx->count += len;
if ((index + len) < bsize)
goto store;
/* process one stored block */
if (index) {
memcpy(ctx->buf + index, data, bsize - index);
cpacf_kimd(ctx->func, ctx->state, ctx->buf, bsize);
data += bsize - index;
len -= bsize - index;
index = 0;
}
/* process as many blocks as possible */
if (len >= bsize) {
n = (len / bsize) * bsize;
cpacf_kimd(ctx->func, ctx->state, data, n);
data += n;
len -= n;
}
store:
if (len)
memcpy(ctx->buf + index , data, len);
return 0;
}
EXPORT_SYMBOL_GPL(s390_sha_update);
static int s390_crypto_shash_parmsize(int func)
{
switch (func) {
case CPACF_KLMD_SHA_1:
return 20;
case CPACF_KLMD_SHA_256:
return 32;
case CPACF_KLMD_SHA_512:
return 64;
case CPACF_KLMD_SHA3_224:
case CPACF_KLMD_SHA3_256:
case CPACF_KLMD_SHA3_384:
case CPACF_KLMD_SHA3_512:
return 200;
default:
return -EINVAL;
}
}
int s390_sha_final(struct shash_desc *desc, u8 *out)
{
struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
unsigned int bsize = crypto_shash_blocksize(desc->tfm);
u64 bits;
unsigned int n;
int mbl_offset;
n = ctx->count % bsize;
bits = ctx->count * 8;
mbl_offset = s390_crypto_shash_parmsize(ctx->func);
if (mbl_offset < 0)
return -EINVAL;
mbl_offset = mbl_offset / sizeof(u32);
/* set total msg bit length (mbl) in CPACF parmblock */
switch (ctx->func) {
case CPACF_KLMD_SHA_1:
case CPACF_KLMD_SHA_256:
memcpy(ctx->state + mbl_offset, &bits, sizeof(bits));
break;
case CPACF_KLMD_SHA_512:
/*
* the SHA512 parmblock has a 128-bit mbl field, clear
* high-order u64 field, copy bits to low-order u64 field
*/
memset(ctx->state + mbl_offset, 0x00, sizeof(bits));
mbl_offset += sizeof(u64) / sizeof(u32);
memcpy(ctx->state + mbl_offset, &bits, sizeof(bits));
break;
case CPACF_KLMD_SHA3_224:
case CPACF_KLMD_SHA3_256:
case CPACF_KLMD_SHA3_384:
case CPACF_KLMD_SHA3_512:
break;
default:
return -EINVAL;
}
cpacf_klmd(ctx->func, ctx->state, ctx->buf, n);
/* copy digest to out */
memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm));
/* wipe context */
memset(ctx, 0, sizeof *ctx);
return 0;
}
EXPORT_SYMBOL_GPL(s390_sha_final);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("s390 SHA cipher common functions");