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: head/sys/geom/eli/g_eli_hmac.c 293306 2016-01-07 05:47:34Z allanjude $");
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
46void
47g_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
78void
79g_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
86void
87g_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
107void
108g_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 */
121void
122g_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}