[mirror_ubuntu-bionic-kernel.git] / arch / s390 / crypto / sha_common.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Cryptographic API.
 *
 * s390 generic implementation of the SHA Secure Hash Algorithms.
 *
 * Copyright IBM Corp. 2007
 * Author(s): Jan Glauber (jang@de.ibm.com)
 */

#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");
Commit	Line	Data
20a884f5	1	// SPDX-License-Identifier: GPL-2.0+
604973f1 JG	2	/*
	3	* Cryptographic API.
	4	*
	5	* s390 generic implementation of the SHA Secure Hash Algorithms.
	6	*
	7	* Copyright IBM Corp. 2007
	8	* Author(s): Jan Glauber (jang@de.ibm.com)
604973f1 JG	9	*/
604973f1 JG	10
563f346d	11	#include <crypto/internal/hash.h>
3a4c5d59	12	#include <linux/module.h>
c7d4d259	13	#include <asm/cpacf.h>
604973f1	14	#include "sha.h"
604973f1	15
563f346d	16	int s390_sha_update(struct shash_desc desc, const u8 data, unsigned int len)
604973f1	17	{
563f346d HX	18	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
563f346d HX	19	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
0177db01	20	unsigned int index, n;
604973f1 JG	21
	22	/* how much is already in the buffer? */
	23	index = ctx->count & (bsize - 1);
	24	ctx->count += len;
	25
	26	if ((index + len) < bsize)
	27	goto store;
	28
	29	/* process one stored block */
	30	if (index) {
	31	memcpy(ctx->buf + index, data, bsize - index);
0177db01	32	cpacf_kimd(ctx->func, ctx->state, ctx->buf, bsize);
604973f1 JG	33	data += bsize - index;
604973f1 JG	34	len -= bsize - index;
9d20b571	35	index = 0;
604973f1 JG	36	}
	37
	38	/* process as many blocks as possible */
	39	if (len >= bsize) {
0177db01 MS	40	n = len & ~(bsize - 1);
	41	cpacf_kimd(ctx->func, ctx->state, data, n);
	42	data += n;
	43	len -= n;
604973f1 JG	44	}
	45	store:
	46	if (len)
	47	memcpy(ctx->buf + index , data, len);
563f346d HX	48
563f346d HX	49	return 0;
604973f1 JG	50	}
	51	EXPORT_SYMBOL_GPL(s390_sha_update);
	52
563f346d	53	int s390_sha_final(struct shash_desc desc, u8 out)
604973f1	54	{
563f346d HX	55	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
563f346d HX	56	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
604973f1	57	u64 bits;
291dc7c0	58	unsigned int index, end, plen;
604973f1	59
291dc7c0 JG	60	/* SHA-512 uses 128 bit padding length */
	61	plen = (bsize > SHA256_BLOCK_SIZE) ? 16 : 8;
	62
604973f1 JG	63	/* must perform manual padding */
604973f1 JG	64	index = ctx->count & (bsize - 1);
291dc7c0	65	end = (index < bsize - plen) ? bsize : (2 * bsize);
604973f1 JG	66
	67	/* start pad with 1 */
	68	ctx->buf[index] = 0x80;
	69	index++;
	70
	71	/* pad with zeros */
	72	memset(ctx->buf + index, 0x00, end - index - 8);
	73
291dc7c0	74	/*
1537a363	75	* Append message length. Well, SHA-512 wants a 128 bit length value,
291dc7c0 JG	76	* nevertheless we use u64, should be enough for now...
291dc7c0 JG	77	*/
604973f1 JG	78	bits = ctx->count * 8;
604973f1 JG	79	memcpy(ctx->buf + end - 8, &bits, sizeof(bits));
0177db01	80	cpacf_kimd(ctx->func, ctx->state, ctx->buf, end);
604973f1 JG	81
604973f1 JG	82	/* copy digest to out */
563f346d	83	memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm));
604973f1 JG	84	/* wipe context */
604973f1 JG	85	memset(ctx, 0, sizeof *ctx);
563f346d HX	86
563f346d HX	87	return 0;
604973f1 JG	88	}
	89	EXPORT_SYMBOL_GPL(s390_sha_final);
	90
	91	MODULE_LICENSE("GPL");
	92	MODULE_DESCRIPTION("s390 SHA cipher common functions");