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], 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 ctx->k_opad[i] = key[i] ^ 0x5c; 70 } 71 bzero(key, sizeof(key)); 72 /* Perform inner SHA512. */ 73 SHA512_Init(&ctx->shactx); 74 SHA512_Update(&ctx->shactx, k_ipad, sizeof(k_ipad)); 75 bzero(k_ipad, sizeof(k_ipad)); 76 } 77 78 void 79 g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data, 80 size_t datasize) 81 { 82 83 SHA512_Update(&ctx->shactx, data, datasize); 84 } 85 86 void 87 g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize) 88 { 89 u_char digest[SHA512_MDLEN]; 90 SHA512_CTX lctx; 91 92 SHA512_Final(digest, &ctx->shactx); 93 /* Perform outer SHA512. */ 94 SHA512_Init(&lctx); 95 SHA512_Update(&lctx, ctx->k_opad, sizeof(ctx->k_opad)); 96 bzero(ctx, sizeof(*ctx)); 97 SHA512_Update(&lctx, digest, sizeof(digest)); 98 SHA512_Final(digest, &lctx); 99 bzero(&lctx, sizeof(lctx)); 100 /* mdsize == 0 means "Give me the whole hash!" */ 101 if (mdsize == 0) 102 mdsize = SHA512_MDLEN; 103 bcopy(digest, md, mdsize); 104 bzero(digest, sizeof(digest)); 105 } 106 107 void 108 g_eli_crypto_hmac(const uint8_t *hkey, size_t hkeysize, const uint8_t *data, 109 size_t datasize, uint8_t *md, size_t mdsize) 110 { 111 struct hmac_ctx ctx; 112 113 g_eli_crypto_hmac_init(&ctx, hkey, hkeysize); 114 g_eli_crypto_hmac_update(&ctx, data, datasize); 115 g_eli_crypto_hmac_final(&ctx, md, mdsize); 116 } 117 118 /* 119 * Here we generate IV. It is unique for every sector. 120 */ 121 void 122 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv, 123 size_t size) 124 { 125 uint8_t off[8]; 126 127 if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0) 128 bcopy(&offset, off, sizeof(off)); 129 else 130 le64enc(off, (uint64_t)offset); 131 132 switch (sc->sc_ealgo) { 133 case CRYPTO_AES_XTS: 134 bcopy(off, iv, sizeof(off)); 135 bzero(iv + sizeof(off), size - sizeof(off)); 136 break; 137 default: 138 { 139 u_char hash[SHA256_DIGEST_LENGTH]; 140 SHA256_CTX ctx; 141 142 /* Copy precalculated SHA256 context for IV-Key. */ 143 bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx)); 144 SHA256_Update(&ctx, off, sizeof(off)); 145 SHA256_Final(hash, &ctx); 146 bcopy(hash, iv, MIN(sizeof(hash), size)); 147 break; 148 } 149 } 150 } 151