/*
* Cryptographic API.
*
* s390 generic implementation of the SHA Secure Hash Algorithms.
*
* Copyright IBM Corp. 2007
* Author(s): Jan Glauber (jang@de.ibm.com)
*
* 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/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 - 1);
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 - 1);
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);
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 index, end, plen;
/* SHA-512 uses 128 bit padding length */
plen = (bsize > SHA256_BLOCK_SIZE) ? 16 : 8;
/* must perform manual padding */
index = ctx->count & (bsize - 1);
end = (index < bsize - plen) ? bsize : (2 * bsize);
/* start pad with 1 */
ctx->buf[index] = 0x80;
index++;
/* pad with zeros */
memset(ctx->buf + index, 0x00, end - index - 8);
/*
* Append message length. Well, SHA-512 wants a 128 bit length value,
* nevertheless we use u64, should be enough for now...
*/
bits = ctx->count * 8;
memcpy(ctx->buf + end - 8, &bits, sizeof(bits));
cpacf_kimd(ctx->func, ctx->state, ctx->buf, end);
/* 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");
