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 /*
23 * Copyright 2022 Tino Reichardt <milky-zfs@mcmilk.de>
24 */
25
26 #include <sys/blake3.h>
27
28 /*
29 * Computes a native 256-bit BLAKE3 MAC checksum. Please note that this
30 * function requires the presence of a ctx_template that should be allocated
31 * using zio_checksum_blake3_tmpl_init.
32 */
33 static void
zio_checksum_blake3_native(const void * buf,uint64_t size,const void * ctx_template,zio_cksum_t * zcp)34 zio_checksum_blake3_native(const void *buf, uint64_t size,
35 const void *ctx_template, zio_cksum_t *zcp)
36 {
37 BLAKE3_CTX ctx;
38
39 ASSERT(ctx_template != 0);
40
41 memcpy(&ctx, ctx_template, sizeof(ctx));
42 Blake3_Update(&ctx, buf, size);
43 Blake3_Final(&ctx, (uint8_t *)zcp);
44
45 memset(&ctx, 0, sizeof (ctx));
46 }
47
48 /*
49 * Byteswapped version of zio_checksum_blake3_native. This just invokes
50 * the native checksum function and byteswaps the resulting checksum (since
51 * BLAKE3 is internally endian-insensitive).
52 */
53 static void
zio_checksum_blake3_byteswap(const void * buf,uint64_t size,const void * ctx_template,zio_cksum_t * zcp)54 zio_checksum_blake3_byteswap(const void *buf, uint64_t size,
55 const void *ctx_template, zio_cksum_t *zcp)
56 {
57 zio_cksum_t tmp;
58
59 ASSERT(ctx_template != 0);
60
61 zio_checksum_blake3_native(buf, size, ctx_template, &tmp);
62 zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]);
63 zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]);
64 zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]);
65 zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]);
66 }
67
68 /*
69 * Allocates a BLAKE3 MAC template suitable for using in BLAKE3 MAC checksum
70 * computations and returns a pointer to it.
71 */
72 static void *
zio_checksum_blake3_tmpl_init(const zio_cksum_salt_t * salt)73 zio_checksum_blake3_tmpl_init(const zio_cksum_salt_t *salt)
74 {
75 BLAKE3_CTX *ctx;
76
77 ASSERT(sizeof (salt->zcs_bytes) == 32);
78
79 /* init reference object */
80 ctx = calloc(1, sizeof(*ctx));
81 Blake3_InitKeyed(ctx, salt->zcs_bytes);
82
83 return (ctx);
84 }
85
86 /*
87 * Frees a BLAKE3 context template previously allocated using
88 * zio_checksum_blake3_tmpl_init.
89 */
90 static void
zio_checksum_blake3_tmpl_free(void * ctx_template)91 zio_checksum_blake3_tmpl_free(void *ctx_template)
92 {
93 BLAKE3_CTX *ctx = ctx_template;
94
95 memset(ctx, 0, sizeof(*ctx));
96 free(ctx);
97 }
98