1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * CDDL HEADER START
4 *
5 * The contents of this file are subject to the terms of the
6 * Common Development and Distribution License (the "License").
7 * You may not use this file except in compliance with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2013 Saso Kiselkov. All rights reserved.
24 * Copyright (c) 2016 by Delphix. All rights reserved.
25 */
26 #include <sys/zfs_context.h>
27 #include <sys/zio.h>
28 #include <sys/zio_checksum.h>
29 #include <sys/skein.h>
30
31 #include <sys/abd.h>
32
33 static int
skein_incremental(void * buf,size_t size,void * arg)34 skein_incremental(void *buf, size_t size, void *arg)
35 {
36 Skein_512_Ctxt_t *ctx = arg;
37 (void) Skein_512_Update(ctx, buf, size);
38 return (0);
39 }
40 /*
41 * Computes a native 256-bit skein MAC checksum. Please note that this
42 * function requires the presence of a ctx_template that should be allocated
43 * using abd_checksum_skein_tmpl_init.
44 */
45 void
abd_checksum_skein_native(abd_t * abd,uint64_t size,const void * ctx_template,zio_cksum_t * zcp)46 abd_checksum_skein_native(abd_t *abd, uint64_t size,
47 const void *ctx_template, zio_cksum_t *zcp)
48 {
49 Skein_512_Ctxt_t ctx;
50
51 ASSERT(ctx_template != NULL);
52 memcpy(&ctx, ctx_template, sizeof (ctx));
53 (void) abd_iterate_func(abd, 0, size, skein_incremental, &ctx);
54 (void) Skein_512_Final(&ctx, (uint8_t *)zcp);
55 memset(&ctx, 0, sizeof (ctx));
56 }
57
58 /*
59 * Byteswapped version of abd_checksum_skein_native. This just invokes
60 * the native checksum function and byteswaps the resulting checksum (since
61 * skein is internally endian-insensitive).
62 */
63 void
abd_checksum_skein_byteswap(abd_t * abd,uint64_t size,const void * ctx_template,zio_cksum_t * zcp)64 abd_checksum_skein_byteswap(abd_t *abd, uint64_t size,
65 const void *ctx_template, zio_cksum_t *zcp)
66 {
67 zio_cksum_t tmp;
68
69 abd_checksum_skein_native(abd, size, ctx_template, &tmp);
70 zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]);
71 zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]);
72 zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]);
73 zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]);
74 }
75
76 /*
77 * Allocates a skein MAC template suitable for using in skein MAC checksum
78 * computations and returns a pointer to it.
79 */
80 void *
abd_checksum_skein_tmpl_init(const zio_cksum_salt_t * salt)81 abd_checksum_skein_tmpl_init(const zio_cksum_salt_t *salt)
82 {
83 Skein_512_Ctxt_t *ctx = kmem_zalloc(sizeof (*ctx), KM_SLEEP);
84
85 (void) Skein_512_InitExt(ctx, sizeof (zio_cksum_t) * 8, 0,
86 salt->zcs_bytes, sizeof (salt->zcs_bytes));
87 return (ctx);
88 }
89
90 /*
91 * Frees a skein context template previously allocated using
92 * zio_checksum_skein_tmpl_init.
93 */
94 void
abd_checksum_skein_tmpl_free(void * ctx_template)95 abd_checksum_skein_tmpl_free(void *ctx_template)
96 {
97 Skein_512_Ctxt_t *ctx = ctx_template;
98
99 memset(ctx, 0, sizeof (*ctx));
100 kmem_free(ctx, sizeof (*ctx));
101 }
102