linux/arch/s390/crypto/ghash_s390.c
Heiko Carstens 0a5f9b382c s390/cpufeature: rework to allow more than only hwcap bits
Rework cpufeature implementation to allow for various cpu feature
indications, which is not only limited to hwcap bits. This is achieved
by adding a sequential list of cpu feature numbers, where each of them
is mapped to an entry which indicates what this number is about.

Each entry contains a type member, which indicates what feature
name space to look into (e.g. hwcap, or cpu facility). If wanted this
allows also to automatically load modules only in e.g. z/VM
configurations.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220713125644.16121-2-seiden@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2022-07-19 16:18:49 +02:00

155 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Cryptographic API.
*
* s390 implementation of the GHASH algorithm for GCM (Galois/Counter Mode).
*
* Copyright IBM Corp. 2011
* Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
*/
#include <crypto/internal/hash.h>
#include <linux/module.h>
#include <linux/cpufeature.h>
#include <asm/cpacf.h>
#define GHASH_BLOCK_SIZE 16
#define GHASH_DIGEST_SIZE 16
struct ghash_ctx {
u8 key[GHASH_BLOCK_SIZE];
};
struct ghash_desc_ctx {
u8 icv[GHASH_BLOCK_SIZE];
u8 key[GHASH_BLOCK_SIZE];
u8 buffer[GHASH_BLOCK_SIZE];
u32 bytes;
};
static int ghash_init(struct shash_desc *desc)
{
struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
memset(dctx, 0, sizeof(*dctx));
memcpy(dctx->key, ctx->key, GHASH_BLOCK_SIZE);
return 0;
}
static int ghash_setkey(struct crypto_shash *tfm,
const u8 *key, unsigned int keylen)
{
struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
if (keylen != GHASH_BLOCK_SIZE)
return -EINVAL;
memcpy(ctx->key, key, GHASH_BLOCK_SIZE);
return 0;
}
static int ghash_update(struct shash_desc *desc,
const u8 *src, unsigned int srclen)
{
struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
unsigned int n;
u8 *buf = dctx->buffer;
if (dctx->bytes) {
u8 *pos = buf + (GHASH_BLOCK_SIZE - dctx->bytes);
n = min(srclen, dctx->bytes);
dctx->bytes -= n;
srclen -= n;
memcpy(pos, src, n);
src += n;
if (!dctx->bytes) {
cpacf_kimd(CPACF_KIMD_GHASH, dctx, buf,
GHASH_BLOCK_SIZE);
}
}
n = srclen & ~(GHASH_BLOCK_SIZE - 1);
if (n) {
cpacf_kimd(CPACF_KIMD_GHASH, dctx, src, n);
src += n;
srclen -= n;
}
if (srclen) {
dctx->bytes = GHASH_BLOCK_SIZE - srclen;
memcpy(buf, src, srclen);
}
return 0;
}
static int ghash_flush(struct ghash_desc_ctx *dctx)
{
u8 *buf = dctx->buffer;
if (dctx->bytes) {
u8 *pos = buf + (GHASH_BLOCK_SIZE - dctx->bytes);
memset(pos, 0, dctx->bytes);
cpacf_kimd(CPACF_KIMD_GHASH, dctx, buf, GHASH_BLOCK_SIZE);
dctx->bytes = 0;
}
return 0;
}
static int ghash_final(struct shash_desc *desc, u8 *dst)
{
struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
int ret;
ret = ghash_flush(dctx);
if (!ret)
memcpy(dst, dctx->icv, GHASH_BLOCK_SIZE);
return ret;
}
static struct shash_alg ghash_alg = {
.digestsize = GHASH_DIGEST_SIZE,
.init = ghash_init,
.update = ghash_update,
.final = ghash_final,
.setkey = ghash_setkey,
.descsize = sizeof(struct ghash_desc_ctx),
.base = {
.cra_name = "ghash",
.cra_driver_name = "ghash-s390",
.cra_priority = 300,
.cra_blocksize = GHASH_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct ghash_ctx),
.cra_module = THIS_MODULE,
},
};
static int __init ghash_mod_init(void)
{
if (!cpacf_query_func(CPACF_KIMD, CPACF_KIMD_GHASH))
return -ENODEV;
return crypto_register_shash(&ghash_alg);
}
static void __exit ghash_mod_exit(void)
{
crypto_unregister_shash(&ghash_alg);
}
module_cpu_feature_match(S390_CPU_FEATURE_MSA, ghash_mod_init);
module_exit(ghash_mod_exit);
MODULE_ALIAS_CRYPTO("ghash");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("GHASH hash function, s390 implementation");