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/zfs_context.h> 27 #include <sys/zio_checksum.h> 28 #include <sys/blake3.h> 29 #include <sys/abd.h> 30 31 static int 32 blake3_incremental(void *buf, size_t size, void *arg) 33 { 34 BLAKE3_CTX *ctx = arg; 35 36 Blake3_Update(ctx, buf, size); 37 38 return (0); 39 } 40 41 /* 42 * Computes a native 256-bit BLAKE3 MAC checksum. Please note that this 43 * function requires the presence of a ctx_template that should be allocated 44 * using abd_checksum_blake3_tmpl_init. 45 */ 46 void 47 abd_checksum_blake3_native(abd_t *abd, uint64_t size, const void *ctx_template, 48 zio_cksum_t *zcp) 49 { 50 ASSERT(ctx_template != NULL); 51 52 #if defined(_KERNEL) 53 kpreempt_disable(); 54 BLAKE3_CTX *ctx = blake3_per_cpu_ctx[CPU_SEQID]; 55 #else 56 BLAKE3_CTX *ctx = kmem_alloc(sizeof (*ctx), KM_SLEEP); 57 #endif 58 59 memcpy(ctx, ctx_template, sizeof (*ctx)); 60 (void) abd_iterate_func(abd, 0, size, blake3_incremental, ctx); 61 Blake3_Final(ctx, (uint8_t *)zcp); 62 63 #if defined(_KERNEL) 64 kpreempt_enable(); 65 #else 66 memset(ctx, 0, sizeof (*ctx)); 67 kmem_free(ctx, sizeof (*ctx)); 68 #endif 69 } 70 71 /* 72 * Byteswapped version of abd_checksum_blake3_native. This just invokes 73 * the native checksum function and byteswaps the resulting checksum (since 74 * BLAKE3 is internally endian-insensitive). 75 */ 76 void 77 abd_checksum_blake3_byteswap(abd_t *abd, uint64_t size, 78 const void *ctx_template, zio_cksum_t *zcp) 79 { 80 zio_cksum_t tmp; 81 82 ASSERT(ctx_template != NULL); 83 84 abd_checksum_blake3_native(abd, size, ctx_template, &tmp); 85 zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]); 86 zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]); 87 zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]); 88 zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]); 89 } 90 91 /* 92 * Allocates a BLAKE3 MAC template suitable for using in BLAKE3 MAC checksum 93 * computations and returns a pointer to it. 94 */ 95 void * 96 abd_checksum_blake3_tmpl_init(const zio_cksum_salt_t *salt) 97 { 98 BLAKE3_CTX *ctx; 99 100 ASSERT(sizeof (salt->zcs_bytes) == 32); 101 102 /* init reference object */ 103 ctx = kmem_zalloc(sizeof (*ctx), KM_SLEEP); 104 Blake3_InitKeyed(ctx, salt->zcs_bytes); 105 106 return (ctx); 107 } 108 109 /* 110 * Frees a BLAKE3 context template previously allocated using 111 * zio_checksum_blake3_tmpl_init. 112 */ 113 void 114 abd_checksum_blake3_tmpl_free(void *ctx_template) 115 { 116 BLAKE3_CTX *ctx = ctx_template; 117 118 memset(ctx, 0, sizeof (*ctx)); 119 kmem_free(ctx, sizeof (*ctx)); 120 } 121