1/*-
2 * Copyright (c) 2005-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3 * Copyright (c) 2015 Allan Jude <allanjude@FreeBSD.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <stdio.h>
29#include <string.h>
30#include <strings.h>
31
32#include "geliboot_internal.h"
33#include "geliboot.h"
34
35int
36geliboot_crypt(u_int algo, geli_op_t enc, u_char *data, size_t datasize,
37    const u_char *key, size_t keysize, u_char *iv)
38{
39	keyInstance aeskey;
40	cipherInstance cipher;
41	struct aes_xts_ctx xtsctx, *ctxp;
42	size_t xts_len;
43	int err, blks;
44
45	switch (algo) {
46	case CRYPTO_AES_CBC:
47		err = rijndael_makeKey(&aeskey, !enc, keysize,
48		    (const char *)key);
49		if (err < 0) {
50			printf("Failed to setup crypo keys: %d\n", err);
51			return (err);
52		}
53
54		err = rijndael_cipherInit(&cipher, MODE_CBC, iv);
55		if (err < 0) {
56			printf("Failed to setup IV: %d\n", err);
57			return (err);
58		}
59
60		switch (enc) {
61		case GELI_DECRYPT:
62			blks = rijndael_blockDecrypt(&cipher, &aeskey, data,
63			    datasize * 8, data);
64			break;
65		case GELI_ENCRYPT:
66			blks = rijndael_blockEncrypt(&cipher, &aeskey, data,
67			    datasize * 8, data);
68			break;
69		}
70		if (datasize != (blks / 8)) {
71			printf("Failed to %s the entire input: %u != %zu\n",
72			    enc ? "decrypt" : "encrypt",
73			    blks, datasize);
74			return (1);
75		}
76		break;
77	case CRYPTO_AES_XTS:
78		xts_len = keysize << 1;
79		ctxp = &xtsctx;
80
81		enc_xform_aes_xts.setkey(ctxp, key, xts_len / 8);
82		enc_xform_aes_xts.reinit(ctxp, iv, AES_XTS_IV_LEN);
83
84		switch (enc) {
85		case GELI_DECRYPT:
86			enc_xform_aes_xts.decrypt_multi(ctxp, data, data,
87			    datasize);
88			break;
89		case GELI_ENCRYPT:
90			enc_xform_aes_xts.encrypt_multi(ctxp, data, data,
91			    datasize);
92			break;
93		}
94		break;
95	default:
96		printf("Unsupported crypto algorithm #%d\n", algo);
97		return (1);
98	}
99
100	return (0);
101}
102
103static int
104g_eli_crypto_cipher(u_int algo, geli_op_t enc, u_char *data, size_t datasize,
105    const u_char *key, size_t keysize)
106{
107	u_char iv[G_ELI_IVKEYLEN];
108
109	explicit_bzero(iv, sizeof(iv));
110	return (geliboot_crypt(algo, enc, data, datasize, key, keysize, iv));
111}
112
113int
114g_eli_crypto_encrypt(u_int algo, u_char *data, size_t datasize,
115    const u_char *key, size_t keysize)
116{
117
118	/* We prefer AES-CBC for metadata protection. */
119	if (algo == CRYPTO_AES_XTS)
120		algo = CRYPTO_AES_CBC;
121
122	return (g_eli_crypto_cipher(algo, GELI_ENCRYPT, data, datasize, key,
123	    keysize));
124}
125
126int
127g_eli_crypto_decrypt(u_int algo, u_char *data, size_t datasize,
128    const u_char *key, size_t keysize)
129{
130
131	/* We prefer AES-CBC for metadata protection. */
132	if (algo == CRYPTO_AES_XTS)
133		algo = CRYPTO_AES_CBC;
134
135	return (g_eli_crypto_cipher(algo, GELI_DECRYPT, data, datasize, key,
136	    keysize));
137}
138