/*
* Cryptographic API.
*
* z990 implementation of the SHA1 Secure Hash Algorithm.
*
* Derived from cryptoapi implementation, adapted for in-place
* scatterlist interface. Originally based on the public domain
* implementation written by Steve Reid.
*
* s390 Version:
* Copyright (C) 2003 IBM Deutschland GmbH, IBM Corporation
* Author(s): Thomas Spatzier (tspat@de.ibm.com)
*
* Derived from "crypto/sha1.c"
* Copyright (c) Alan Smithee.
* Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
* Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
*
* 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 <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/crypto.h>
#include <asm/scatterlist.h>
#include <asm/byteorder.h>
#include "crypt_z990.h"
#define SHA1_DIGEST_SIZE 20
#define SHA1_BLOCK_SIZE 64
struct crypt_z990_sha1_ctx {
u64 count;
u32 state[5];
u32 buf_len;
u8 buffer[2 * SHA1_BLOCK_SIZE];
};
static void
sha1_init(void *ctx)
{
static const struct crypt_z990_sha1_ctx initstate = {
.state = {
0x67452301,
0xEFCDAB89,
0x98BADCFE,
0x10325476,
0xC3D2E1F0
},
};
memcpy(ctx, &initstate, sizeof(initstate));
}
static void
sha1_update(void *ctx, const u8 *data, unsigned int len)
{
struct crypt_z990_sha1_ctx *sctx;
long imd_len;
sctx = ctx;
sctx->count += len * 8; //message bit length
//anything in buffer yet? -> must be completed
if (sctx->buf_len && (sctx->buf_len + len) >= SHA1_BLOCK_SIZE) {
//complete full block and hash
memcpy(sctx->buffer + sctx->buf_len, data,
SHA1_BLOCK_SIZE - sctx->buf_len);
crypt_z990_kimd(KIMD_SHA_1, sctx->state, sctx->buffer,
SHA1_BLOCK_SIZE);
data += SHA1_BLOCK_SIZE - sctx->buf_len;
len -= SHA1_BLOCK_SIZE - sctx->buf_len;
sctx->buf_len = 0;
}
//rest of data contains full blocks?
imd_len = len & ~0x3ful;
if (imd_len){
crypt_z990_kimd(KIMD_SHA_1, sctx->state, data, imd_len);
data += imd_len;
len -= imd_len;
}
//anything left? store in buffer
if (len){
memcpy(sctx->buffer + sctx->buf_len , data, len);
sctx->buf_len += len;
}
}
static void
pad_message(struct crypt_z990_sha1_ctx* sctx)
{
int index;
index = sctx->buf_len;
sctx->buf_len = (sctx->buf_len < 56)?
SHA1_BLOCK_SIZE:2 * SHA1_BLOCK_SIZE;
//start pad with 1
sctx->buffer[index] = 0x80;
//pad with zeros
index++;
memset(sctx->buffer + index, 0x00, sctx->buf_len - index);
//append length
memcpy(sctx->buffer + sctx->buf_len - 8, &sctx->count,
sizeof sctx->count);
}
/* Add padding and return the message digest. */
static void
sha1_final(void* ctx, u8 *out)
{
struct crypt_z990_sha1_ctx *sctx = ctx;
//must perform manual padding
pad_message(sctx);
crypt_z990_kimd(KIMD_SHA_1, sctx->state, sctx->buffer, sctx->buf_len);
//copy digest to out
memcpy(out, sctx->state, SHA1_DIGEST_SIZE);
/* Wipe context */
memset(sctx, 0, sizeof *sctx);
}
static struct crypto_alg alg = {
.cra_name = "sha1",
.cra_flags = CRYPTO_ALG_TYPE_DIGEST,
.cra_blocksize = SHA1_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crypt_z990_sha1_ctx),
.cra_module = THIS_MODULE,
.cra_list = LIST_HEAD_INIT(alg.cra_list),
.cra_u = { .digest = {
.dia_digestsize = SHA1_DIGEST_SIZE,
.dia_init = sha1_init,
.dia_update = sha1_update,
.dia_final = sha1_final } }
};
static int
init(void)
{
int ret = -ENOSYS;
if (crypt_z990_func_available(KIMD_SHA_1)){
ret = crypto_register_alg(&alg);
if (ret == 0){
printk(KERN_INFO "crypt_z990: sha1_z990 loaded.\n");
}
}
return ret;
}
static void __exit
fini(void)
{
crypto_unregister_alg(&alg);
}
module_init(init);
module_exit(fini);
MODULE_ALIAS("sha1");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
