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 #else 36 #include <stdint.h> 37 #include <string.h> 38 #include <strings.h> 39 #include <errno.h> 40 #include <assert.h> 41 #include <openssl/evp.h> 42 #define _OpenSSL_ 43 #endif 44 #include <geom/eli/g_eli.h> 45 46 void 47 g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const uint8_t *hkey, 48 size_t hkeylen) 49 { 50 u_char k_ipad[128], k_opad[128], key[128]; 51 SHA512_CTX lctx; 52 u_int i; 53 54 bzero(key, sizeof(key)); 55 if (hkeylen == 0) 56 ; /* do nothing */ 57 else if (hkeylen <= 128) 58 bcopy(hkey, key, hkeylen); 59 else { 60 /* If key is longer than 128 bytes reset it to key = SHA512(key). */ 61 SHA512_Init(&lctx); 62 SHA512_Update(&lctx, hkey, hkeylen); 63 SHA512_Final(key, &lctx); 64 } 65 66 /* XOR key with ipad and opad values. */ 67 for (i = 0; i < sizeof(key); i++) { 68 k_ipad[i] = key[i] ^ 0x36; 69 k_opad[i] = key[i] ^ 0x5c; 70 } 71 explicit_bzero(key, sizeof(key)); 72 /* Start inner SHA512. */ 73 SHA512_Init(&ctx->innerctx); 74 SHA512_Update(&ctx->innerctx, k_ipad, sizeof(k_ipad)); 75 explicit_bzero(k_ipad, sizeof(k_ipad)); 76 /* Start outer SHA512. */ 77 SHA512_Init(&ctx->outerctx); 78 SHA512_Update(&ctx->outerctx, k_opad, sizeof(k_opad)); 79 explicit_bzero(k_opad, sizeof(k_opad)); 80 } 81 82 void 83 g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data, 84 size_t datasize) 85 { 86 87 SHA512_Update(&ctx->innerctx, data, datasize); 88 } 89 90 void 91 g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize) 92 { 93 u_char digest[SHA512_MDLEN]; 94 95 /* Complete inner hash */ 96 SHA512_Final(digest, &ctx->innerctx); 97 98 /* Complete outer hash */ 99 SHA512_Update(&ctx->outerctx, digest, sizeof(digest)); 100 SHA512_Final(digest, &ctx->outerctx); 101 102 explicit_bzero(ctx, sizeof(*ctx)); 103 /* mdsize == 0 means "Give me the whole hash!" */ 104 if (mdsize == 0) 105 mdsize = SHA512_MDLEN; 106 bcopy(digest, md, mdsize); 107 explicit_bzero(digest, sizeof(digest)); 108 } 109 110 void 111 g_eli_crypto_hmac(const uint8_t *hkey, size_t hkeysize, const uint8_t *data, 112 size_t datasize, uint8_t *md, size_t mdsize) 113 { 114 struct hmac_ctx ctx; 115 116 g_eli_crypto_hmac_init(&ctx, hkey, hkeysize); 117 g_eli_crypto_hmac_update(&ctx, data, datasize); 118 g_eli_crypto_hmac_final(&ctx, md, mdsize); 119 } 120 121 /* 122 * Here we generate IV. It is unique for every sector. 123 */ 124 void 125 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv, 126 size_t size) 127 { 128 uint8_t off[8]; 129 130 if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0) 131 bcopy(&offset, off, sizeof(off)); 132 else 133 le64enc(off, (uint64_t)offset); 134 135 switch (sc->sc_ealgo) { 136 case CRYPTO_AES_XTS: 137 bcopy(off, iv, sizeof(off)); 138 bzero(iv + sizeof(off), size - sizeof(off)); 139 break; 140 default: 141 { 142 u_char hash[SHA256_DIGEST_LENGTH]; 143 SHA256_CTX ctx; 144 145 /* Copy precalculated SHA256 context for IV-Key. */ 146 bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx)); 147 SHA256_Update(&ctx, off, sizeof(off)); 148 SHA256_Final(hash, &ctx); 149 bcopy(hash, iv, MIN(sizeof(hash), size)); 150 break; 151 } 152 } 153 } 154