xref: /freebsd/sys/geom/eli/g_eli_crypto.c (revision c8e7f78a3d28ff6e6223ed136ada8e1e2f34965e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2005-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #ifdef _KERNEL
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.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 #ifdef _KERNEL
46 MALLOC_DECLARE(M_ELI);
47 
48 static int
49 g_eli_crypto_done(struct cryptop *crp)
50 {
51 
52 	crp->crp_opaque = (void *)crp;
53 	wakeup(crp);
54 	return (0);
55 }
56 
57 static int
58 g_eli_crypto_cipher(u_int algo, int enc, u_char *data, size_t datasize,
59     const u_char *key, size_t keysize)
60 {
61 	struct crypto_session_params csp;
62 	struct cryptop *crp;
63 	crypto_session_t sid;
64 	int error;
65 
66 	KASSERT(algo != CRYPTO_AES_XTS,
67 	    ("%s: CRYPTO_AES_XTS unexpected here", __func__));
68 
69 	memset(&csp, 0, sizeof(csp));
70 	csp.csp_mode = CSP_MODE_CIPHER;
71 	csp.csp_cipher_alg = algo;
72 	csp.csp_ivlen = g_eli_ivlen(algo);
73 	csp.csp_cipher_key = key;
74 	csp.csp_cipher_klen = keysize / 8;
75 	error = crypto_newsession(&sid, &csp, CRYPTOCAP_F_SOFTWARE);
76 	if (error != 0)
77 		return (error);
78 	crp = crypto_getreq(sid, M_NOWAIT);
79 	if (crp == NULL) {
80 		crypto_freesession(sid);
81 		return (ENOMEM);
82 	}
83 
84 	crp->crp_payload_start = 0;
85 	crp->crp_payload_length = datasize;
86 	crp->crp_flags = CRYPTO_F_CBIFSYNC | CRYPTO_F_IV_SEPARATE;
87 	crp->crp_op = enc ? CRYPTO_OP_ENCRYPT : CRYPTO_OP_DECRYPT;
88 	memset(crp->crp_iv, 0, sizeof(crp->crp_iv));
89 
90 	crp->crp_opaque = NULL;
91 	crp->crp_callback = g_eli_crypto_done;
92 	crypto_use_buf(crp, data, datasize);
93 
94 	error = crypto_dispatch(crp);
95 	if (error == 0) {
96 		while (crp->crp_opaque == NULL)
97 			tsleep(crp, PRIBIO, "geli", hz / 5);
98 		error = crp->crp_etype;
99 	}
100 
101 	crypto_freereq(crp);
102 	crypto_freesession(sid);
103 	return (error);
104 }
105 #else	/* !_KERNEL */
106 static int
107 g_eli_crypto_cipher(u_int algo, int enc, u_char *data, size_t datasize,
108     const u_char *key, size_t keysize)
109 {
110 	EVP_CIPHER_CTX *ctx;
111 	const EVP_CIPHER *type;
112 	u_char iv[G_ELI_IVKEYLEN];
113 	int outsize;
114 
115 	assert(algo != CRYPTO_AES_XTS);
116 
117 	switch (algo) {
118 	case CRYPTO_NULL_CBC:
119 		type = EVP_enc_null();
120 		break;
121 	case CRYPTO_AES_CBC:
122 		switch (keysize) {
123 		case 128:
124 			type = EVP_aes_128_cbc();
125 			break;
126 		case 192:
127 			type = EVP_aes_192_cbc();
128 			break;
129 		case 256:
130 			type = EVP_aes_256_cbc();
131 			break;
132 		default:
133 			return (EINVAL);
134 		}
135 		break;
136 #ifndef OPENSSL_NO_CAMELLIA
137 	case CRYPTO_CAMELLIA_CBC:
138 		switch (keysize) {
139 		case 128:
140 			type = EVP_camellia_128_cbc();
141 			break;
142 		case 192:
143 			type = EVP_camellia_192_cbc();
144 			break;
145 		case 256:
146 			type = EVP_camellia_256_cbc();
147 			break;
148 		default:
149 			return (EINVAL);
150 		}
151 		break;
152 #endif
153 	default:
154 		return (EINVAL);
155 	}
156 
157 	ctx = EVP_CIPHER_CTX_new();
158 	if (ctx == NULL)
159 		return (ENOMEM);
160 
161 	EVP_CipherInit_ex(ctx, type, NULL, NULL, NULL, enc);
162 	EVP_CIPHER_CTX_set_key_length(ctx, keysize / 8);
163 	EVP_CIPHER_CTX_set_padding(ctx, 0);
164 	bzero(iv, sizeof(iv));
165 	EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, enc);
166 
167 	if (EVP_CipherUpdate(ctx, data, &outsize, data, datasize) == 0) {
168 		EVP_CIPHER_CTX_free(ctx);
169 		return (EINVAL);
170 	}
171 	assert(outsize == (int)datasize);
172 
173 	if (EVP_CipherFinal_ex(ctx, data + outsize, &outsize) == 0) {
174 		EVP_CIPHER_CTX_free(ctx);
175 		return (EINVAL);
176 	}
177 	assert(outsize == 0);
178 
179 	EVP_CIPHER_CTX_free(ctx);
180 	return (0);
181 }
182 #endif	/* !_KERNEL */
183 
184 int
185 g_eli_crypto_encrypt(u_int algo, u_char *data, size_t datasize,
186     const u_char *key, size_t keysize)
187 {
188 
189 	/* We prefer AES-CBC for metadata protection. */
190 	if (algo == CRYPTO_AES_XTS)
191 		algo = CRYPTO_AES_CBC;
192 
193 	return (g_eli_crypto_cipher(algo, 1, data, datasize, key, keysize));
194 }
195 
196 int
197 g_eli_crypto_decrypt(u_int algo, u_char *data, size_t datasize,
198     const u_char *key, size_t keysize)
199 {
200 
201 	/* We prefer AES-CBC for metadata protection. */
202 	if (algo == CRYPTO_AES_XTS)
203 		algo = CRYPTO_AES_CBC;
204 
205 	return (g_eli_crypto_cipher(algo, 0, data, datasize, key, keysize));
206 }
207