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 * Copyright (c) 2016 by Delphix. All rights reserved. 24 */ 25 #include <sys/zfs_context.h> 26 #include <sys/zio.h> 27 #include <sys/zio_checksum.h> 28 #include <sys/skein.h> 29 30 #include <sys/abd.h> 31 32 static int 33 skein_incremental(void *buf, size_t size, void *arg) 34 { 35 Skein_512_Ctxt_t *ctx = arg; 36 (void) Skein_512_Update(ctx, buf, size); 37 return (0); 38 } 39 /* 40 * Computes a native 256-bit skein MAC checksum. Please note that this 41 * function requires the presence of a ctx_template that should be allocated 42 * using abd_checksum_skein_tmpl_init. 43 */ 44 void 45 abd_checksum_skein_native(abd_t *abd, uint64_t size, 46 const void *ctx_template, zio_cksum_t *zcp) 47 { 48 Skein_512_Ctxt_t ctx; 49 50 ASSERT(ctx_template != NULL); 51 memcpy(&ctx, ctx_template, sizeof (ctx)); 52 (void) abd_iterate_func(abd, 0, size, skein_incremental, &ctx); 53 (void) Skein_512_Final(&ctx, (uint8_t *)zcp); 54 memset(&ctx, 0, sizeof (ctx)); 55 } 56 57 /* 58 * Byteswapped version of abd_checksum_skein_native. This just invokes 59 * the native checksum function and byteswaps the resulting checksum (since 60 * skein is internally endian-insensitive). 61 */ 62 void 63 abd_checksum_skein_byteswap(abd_t *abd, uint64_t size, 64 const void *ctx_template, zio_cksum_t *zcp) 65 { 66 zio_cksum_t tmp; 67 68 abd_checksum_skein_native(abd, size, ctx_template, &tmp); 69 zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]); 70 zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]); 71 zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]); 72 zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]); 73 } 74 75 /* 76 * Allocates a skein MAC template suitable for using in skein MAC checksum 77 * computations and returns a pointer to it. 78 */ 79 void * 80 abd_checksum_skein_tmpl_init(const zio_cksum_salt_t *salt) 81 { 82 Skein_512_Ctxt_t *ctx = kmem_zalloc(sizeof (*ctx), KM_SLEEP); 83 84 (void) Skein_512_InitExt(ctx, sizeof (zio_cksum_t) * 8, 0, 85 salt->zcs_bytes, sizeof (salt->zcs_bytes)); 86 return (ctx); 87 } 88 89 /* 90 * Frees a skein context template previously allocated using 91 * zio_checksum_skein_tmpl_init. 92 */ 93 void 94 abd_checksum_skein_tmpl_free(void *ctx_template) 95 { 96 Skein_512_Ctxt_t *ctx = ctx_template; 97 98 memset(ctx, 0, sizeof (*ctx)); 99 kmem_free(ctx, sizeof (*ctx)); 100 } 101