linux/arch/s390/crypto/sha_common.c
Martin Schwidefsky c7d4d259b7 s390/crypto: cleanup and move the header with the cpacf definitions
The CPACF instructions are going be used in KVM as well, move the
defines and the inline functions from arch/s390/crypt/crypt_s390.h
to arch/s390/include/asm. Rename the header to cpacf.h and replace
the crypt_s390_xxx names with cpacf_xxx.

While we are at it, cleanup the header as well. The encoding for
the CPACF operations is odd, there is an enum for each of the CPACF
instructions with the hardware function code in the lower 8 bits of
each entry and a software defined number for the CPACF instruction
in the upper 8 bits. Remove the superfluous software number and
replace the enums with simple defines.

The crypt_s390_func_available() function tests for the presence
of a specific CPACF operations. The new name of the function is
cpacf_query and it works slightly different than before. It gets
passed an opcode of an CPACF instruction and a function code for
this instruction. The facility_mask parameter is gone, the opcode
is used to find the correct MSA facility bit to check if the CPACF
instruction itself is available. If it is the query function of the
given instruction is used to test if the requested CPACF operation
is present.

Acked-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-04-15 18:16:40 +02:00

107 lines
2.5 KiB
C

/*
* 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;
int ret;
/* 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);
ret = cpacf_kimd(ctx->func, ctx->state, ctx->buf, bsize);
if (ret != bsize)
return -EIO;
data += bsize - index;
len -= bsize - index;
index = 0;
}
/* process as many blocks as possible */
if (len >= bsize) {
ret = cpacf_kimd(ctx->func, ctx->state, data,
len & ~(bsize - 1));
if (ret != (len & ~(bsize - 1)))
return -EIO;
data += ret;
len -= ret;
}
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;
int ret;
/* 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));
ret = cpacf_kimd(ctx->func, ctx->state, ctx->buf, end);
if (ret != end)
return -EIO;
/* 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");