1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2013 Saso Kiselkov. All rights reserved.
23 */
24 #include <sys/skein.h>
25
26 /*
27 * Computes a native 256-bit skein MAC checksum. Please note that this
28 * function requires the presence of a ctx_template that should be allocated
29 * using zio_checksum_skein_tmpl_init.
30 */
31 /*ARGSUSED*/
32 static void
zio_checksum_skein_native(const void * buf,uint64_t size,const void * ctx_template,zio_cksum_t * zcp)33 zio_checksum_skein_native(const void *buf, uint64_t size,
34 const void *ctx_template, zio_cksum_t *zcp)
35 {
36 Skein_512_Ctxt_t ctx;
37
38 ASSERT(ctx_template != NULL);
39 bcopy(ctx_template, &ctx, sizeof (ctx));
40 (void) Skein_512_Update(&ctx, buf, size);
41 (void) Skein_512_Final(&ctx, (uint8_t *)zcp);
42 bzero(&ctx, sizeof (ctx));
43 }
44
45 /*
46 * Byteswapped version of zio_checksum_skein_native. This just invokes
47 * the native checksum function and byteswaps the resulting checksum (since
48 * skein is internally endian-insensitive).
49 */
50 static void
zio_checksum_skein_byteswap(const void * buf,uint64_t size,const void * ctx_template,zio_cksum_t * zcp)51 zio_checksum_skein_byteswap(const void *buf, uint64_t size,
52 const void *ctx_template, zio_cksum_t *zcp)
53 {
54 zio_cksum_t tmp;
55
56 zio_checksum_skein_native(buf, size, ctx_template, &tmp);
57 zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]);
58 zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]);
59 zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]);
60 zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]);
61 }
62
63 /*
64 * Allocates a skein MAC template suitable for using in skein MAC checksum
65 * computations and returns a pointer to it.
66 */
67 static void *
zio_checksum_skein_tmpl_init(const zio_cksum_salt_t * salt)68 zio_checksum_skein_tmpl_init(const zio_cksum_salt_t *salt)
69 {
70 Skein_512_Ctxt_t *ctx;
71
72 ctx = malloc(sizeof (*ctx));
73 bzero(ctx, sizeof (*ctx));
74 (void) Skein_512_InitExt(ctx, sizeof (zio_cksum_t) * 8, 0,
75 salt->zcs_bytes, sizeof (salt->zcs_bytes));
76 return (ctx);
77 }
78
79 /*
80 * Frees a skein context template previously allocated using
81 * zio_checksum_skein_tmpl_init.
82 */
83 static void
zio_checksum_skein_tmpl_free(void * ctx_template)84 zio_checksum_skein_tmpl_free(void *ctx_template)
85 {
86 Skein_512_Ctxt_t *ctx = ctx_template;
87
88 bzero(ctx, sizeof (*ctx));
89 free(ctx);
90 }
91