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/param.h> 28 #ifdef _KERNEL 29 #include <sys/systm.h> 30 #include <sys/kernel.h> 31 #include <sys/malloc.h> 32 #elif defined(_STANDALONE) 33 #include "stand.h" 34 #else 35 #include <stdint.h> 36 #include <string.h> 37 #include <strings.h> 38 #include <errno.h> 39 #include <assert.h> 40 #include <openssl/evp.h> 41 #define _OpenSSL_ 42 #endif 43 #include <geom/eli/g_eli.h> 44 45 void 46 g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const char *hkey, 47 size_t hkeylen) 48 { 49 u_char k_ipad[128], k_opad[128], key[128]; 50 SHA512_CTX lctx; 51 u_int i; 52 53 bzero(key, sizeof(key)); 54 if (hkeylen == 0) 55 ; /* do nothing */ 56 else if (hkeylen <= 128) 57 bcopy(hkey, key, hkeylen); 58 else { 59 /* If key is longer than 128 bytes reset it to key = SHA512(key). */ 60 SHA512_Init(&lctx); 61 SHA512_Update(&lctx, hkey, hkeylen); 62 SHA512_Final(key, &lctx); 63 } 64 65 /* XOR key with ipad and opad values. */ 66 for (i = 0; i < sizeof(key); i++) { 67 k_ipad[i] = key[i] ^ 0x36; 68 k_opad[i] = key[i] ^ 0x5c; 69 } 70 explicit_bzero(key, sizeof(key)); 71 /* Start inner SHA512. */ 72 SHA512_Init(&ctx->innerctx); 73 SHA512_Update(&ctx->innerctx, k_ipad, sizeof(k_ipad)); 74 explicit_bzero(k_ipad, sizeof(k_ipad)); 75 /* Start outer SHA512. */ 76 SHA512_Init(&ctx->outerctx); 77 SHA512_Update(&ctx->outerctx, k_opad, sizeof(k_opad)); 78 explicit_bzero(k_opad, sizeof(k_opad)); 79 } 80 81 void 82 g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data, 83 size_t datasize) 84 { 85 86 SHA512_Update(&ctx->innerctx, data, datasize); 87 } 88 89 void 90 g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize) 91 { 92 u_char digest[SHA512_MDLEN]; 93 94 /* Complete inner hash */ 95 SHA512_Final(digest, &ctx->innerctx); 96 97 /* Complete outer hash */ 98 SHA512_Update(&ctx->outerctx, digest, sizeof(digest)); 99 SHA512_Final(digest, &ctx->outerctx); 100 101 explicit_bzero(ctx, sizeof(*ctx)); 102 /* mdsize == 0 means "Give me the whole hash!" */ 103 if (mdsize == 0) 104 mdsize = SHA512_MDLEN; 105 bcopy(digest, md, mdsize); 106 explicit_bzero(digest, sizeof(digest)); 107 } 108 109 void 110 g_eli_crypto_hmac(const char *hkey, size_t hkeysize, const uint8_t *data, 111 size_t datasize, uint8_t *md, size_t mdsize) 112 { 113 struct hmac_ctx ctx; 114 115 g_eli_crypto_hmac_init(&ctx, hkey, hkeysize); 116 g_eli_crypto_hmac_update(&ctx, data, datasize); 117 g_eli_crypto_hmac_final(&ctx, md, mdsize); 118 } 119 120 /* 121 * Here we generate IV. It is unique for every sector. 122 */ 123 void 124 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv, 125 size_t size) 126 { 127 uint8_t off[8]; 128 129 if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0) 130 bcopy(&offset, off, sizeof(off)); 131 else 132 le64enc(off, (uint64_t)offset); 133 134 switch (sc->sc_ealgo) { 135 case CRYPTO_AES_XTS: 136 bcopy(off, iv, sizeof(off)); 137 bzero(iv + sizeof(off), size - sizeof(off)); 138 break; 139 default: 140 { 141 u_char hash[SHA256_DIGEST_LENGTH]; 142 SHA256_CTX ctx; 143 144 /* Copy precalculated SHA256 context for IV-Key. */ 145 bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx)); 146 SHA256_Update(&ctx, off, sizeof(off)); 147 SHA256_Final(hash, &ctx); 148 bcopy(hash, iv, MIN(sizeof(hash), size)); 149 break; 150 } 151 } 152 } 153