[mirror_ubuntu-bionic-kernel.git] / arch / s390 / crypto / sha_common.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 "sha.h"
#include "crypt_s390.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 = crypt_s390_kimd(ctx->func, ctx->state, ctx->buf, bsize);
		BUG_ON(ret != bsize);
		data += bsize - index;
		len -= bsize - index;
	}

	/* process as many blocks as possible */
	if (len >= bsize) {
		ret = crypt_s390_kimd(ctx->func, ctx->state, data,
				      len & ~(bsize - 1));
		BUG_ON(ret != (len & ~(bsize - 1)));
		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 = crypt_s390_kimd(ctx->func, ctx->state, ctx->buf, end);
	BUG_ON(ret != 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");
Commit	Line	Data
604973f1 JG	1	/*
	2	* Cryptographic API.
	3	*
	4	* s390 generic implementation of the SHA Secure Hash Algorithms.
	5	*
	6	* Copyright IBM Corp. 2007
	7	* Author(s): Jan Glauber (jang@de.ibm.com)
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
	11	* Software Foundation; either version 2 of the License, or (at your option)
	12	* any later version.
	13	*
	14	*/
	15
563f346d	16	#include <crypto/internal/hash.h>
604973f1 JG	17	#include "sha.h"
	18	#include "crypt_s390.h"
	19
563f346d	20	int s390_sha_update(struct shash_desc desc, const u8 data, unsigned int len)
604973f1	21	{
563f346d HX	22	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
563f346d HX	23	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
604973f1 JG	24	unsigned int index;
	25	int ret;
	26
	27	/* how much is already in the buffer? */
	28	index = ctx->count & (bsize - 1);
	29	ctx->count += len;
	30
	31	if ((index + len) < bsize)
	32	goto store;
	33
	34	/* process one stored block */
	35	if (index) {
	36	memcpy(ctx->buf + index, data, bsize - index);
	37	ret = crypt_s390_kimd(ctx->func, ctx->state, ctx->buf, bsize);
	38	BUG_ON(ret != bsize);
	39	data += bsize - index;
	40	len -= bsize - index;
	41	}
	42
	43	/* process as many blocks as possible */
	44	if (len >= bsize) {
	45	ret = crypt_s390_kimd(ctx->func, ctx->state, data,
	46	len & ~(bsize - 1));
	47	BUG_ON(ret != (len & ~(bsize - 1)));
	48	data += ret;
	49	len -= ret;
	50	}
	51	store:
	52	if (len)
	53	memcpy(ctx->buf + index , data, len);
563f346d HX	54
563f346d HX	55	return 0;
604973f1 JG	56	}
	57	EXPORT_SYMBOL_GPL(s390_sha_update);
	58
563f346d	59	int s390_sha_final(struct shash_desc desc, u8 out)
604973f1	60	{
563f346d HX	61	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
563f346d HX	62	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
604973f1	63	u64 bits;
291dc7c0	64	unsigned int index, end, plen;
604973f1 JG	65	int ret;
604973f1 JG	66
291dc7c0 JG	67	/* SHA-512 uses 128 bit padding length */
	68	plen = (bsize > SHA256_BLOCK_SIZE) ? 16 : 8;
	69
604973f1 JG	70	/* must perform manual padding */
604973f1 JG	71	index = ctx->count & (bsize - 1);
291dc7c0	72	end = (index < bsize - plen) ? bsize : (2 * bsize);
604973f1 JG	73
	74	/* start pad with 1 */
	75	ctx->buf[index] = 0x80;
	76	index++;
	77
	78	/* pad with zeros */
	79	memset(ctx->buf + index, 0x00, end - index - 8);
	80
291dc7c0	81	/*
1537a363	82	* Append message length. Well, SHA-512 wants a 128 bit length value,
291dc7c0 JG	83	* nevertheless we use u64, should be enough for now...
291dc7c0 JG	84	*/
604973f1 JG	85	bits = ctx->count * 8;
	86	memcpy(ctx->buf + end - 8, &bits, sizeof(bits));
	87
	88	ret = crypt_s390_kimd(ctx->func, ctx->state, ctx->buf, end);
	89	BUG_ON(ret != end);
	90
	91	/* copy digest to out */
563f346d	92	memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm));
604973f1 JG	93	/* wipe context */
604973f1 JG	94	memset(ctx, 0, sizeof *ctx);
563f346d HX	95
563f346d HX	96	return 0;
604973f1 JG	97	}
	98	EXPORT_SYMBOL_GPL(s390_sha_final);
	99
	100	MODULE_LICENSE("GPL");
	101	MODULE_DESCRIPTION("s390 SHA cipher common functions");