1 /*- 2 * Copyright (c) 2005-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #ifdef _KERNEL 32 #include <sys/systm.h> 33 #include <sys/kernel.h> 34 #include <sys/malloc.h> 35 #elif defined(_STANDALONE) 36 #include "stand.h" 37 #else 38 #include <stdint.h> 39 #include <string.h> 40 #include <strings.h> 41 #include <errno.h> 42 #include <assert.h> 43 #include <openssl/evp.h> 44 #define _OpenSSL_ 45 #endif 46 #include <geom/eli/g_eli.h> 47 48 void 49 g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const char *hkey, 50 size_t hkeylen) 51 { 52 u_char k_ipad[128], k_opad[128], key[128]; 53 SHA512_CTX lctx; 54 u_int i; 55 56 bzero(key, sizeof(key)); 57 if (hkeylen == 0) 58 ; /* do nothing */ 59 else if (hkeylen <= 128) 60 bcopy(hkey, key, hkeylen); 61 else { 62 /* If key is longer than 128 bytes reset it to key = SHA512(key). */ 63 SHA512_Init(&lctx); 64 SHA512_Update(&lctx, hkey, hkeylen); 65 SHA512_Final(key, &lctx); 66 } 67 68 /* XOR key with ipad and opad values. */ 69 for (i = 0; i < sizeof(key); i++) { 70 k_ipad[i] = key[i] ^ 0x36; 71 k_opad[i] = key[i] ^ 0x5c; 72 } 73 explicit_bzero(key, sizeof(key)); 74 /* Start inner SHA512. */ 75 SHA512_Init(&ctx->innerctx); 76 SHA512_Update(&ctx->innerctx, k_ipad, sizeof(k_ipad)); 77 explicit_bzero(k_ipad, sizeof(k_ipad)); 78 /* Start outer SHA512. */ 79 SHA512_Init(&ctx->outerctx); 80 SHA512_Update(&ctx->outerctx, k_opad, sizeof(k_opad)); 81 explicit_bzero(k_opad, sizeof(k_opad)); 82 } 83 84 void 85 g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data, 86 size_t datasize) 87 { 88 89 SHA512_Update(&ctx->innerctx, data, datasize); 90 } 91 92 void 93 g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize) 94 { 95 u_char digest[SHA512_MDLEN]; 96 97 /* Complete inner hash */ 98 SHA512_Final(digest, &ctx->innerctx); 99 100 /* Complete outer hash */ 101 SHA512_Update(&ctx->outerctx, digest, sizeof(digest)); 102 SHA512_Final(digest, &ctx->outerctx); 103 104 explicit_bzero(ctx, sizeof(*ctx)); 105 /* mdsize == 0 means "Give me the whole hash!" */ 106 if (mdsize == 0) 107 mdsize = SHA512_MDLEN; 108 bcopy(digest, md, mdsize); 109 explicit_bzero(digest, sizeof(digest)); 110 } 111 112 void 113 g_eli_crypto_hmac(const char *hkey, size_t hkeysize, const uint8_t *data, 114 size_t datasize, uint8_t *md, size_t mdsize) 115 { 116 struct hmac_ctx ctx; 117 118 g_eli_crypto_hmac_init(&ctx, hkey, hkeysize); 119 g_eli_crypto_hmac_update(&ctx, data, datasize); 120 g_eli_crypto_hmac_final(&ctx, md, mdsize); 121 } 122 123 /* 124 * Here we generate IV. It is unique for every sector. 125 */ 126 void 127 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv, 128 size_t size) 129 { 130 uint8_t off[8]; 131 132 if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0) 133 bcopy(&offset, off, sizeof(off)); 134 else 135 le64enc(off, (uint64_t)offset); 136 137 switch (sc->sc_ealgo) { 138 case CRYPTO_AES_XTS: 139 bcopy(off, iv, sizeof(off)); 140 bzero(iv + sizeof(off), size - sizeof(off)); 141 break; 142 default: 143 { 144 u_char hash[SHA256_DIGEST_LENGTH]; 145 SHA256_CTX ctx; 146 147 /* Copy precalculated SHA256 context for IV-Key. */ 148 bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx)); 149 SHA256_Update(&ctx, off, sizeof(off)); 150 SHA256_Final(hash, &ctx); 151 bcopy(hash, iv, MIN(sizeof(hash), size)); 152 break; 153 } 154 } 155 } 156