1 /*
2 * QEMU Crypto cipher algorithms
3 *
4 * Copyright (c) 2015 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "qemu/host-utils.h"
23 #include "qapi/error.h"
24 #include "crypto/cipher.h"
25 #include "cipherpriv.h"
26
27
28 static const size_t alg_key_len[QCRYPTO_CIPHER_ALG__MAX] = {
29 [QCRYPTO_CIPHER_ALG_AES_128] = 16,
30 [QCRYPTO_CIPHER_ALG_AES_192] = 24,
31 [QCRYPTO_CIPHER_ALG_AES_256] = 32,
32 [QCRYPTO_CIPHER_ALG_DES] = 8,
33 [QCRYPTO_CIPHER_ALG_3DES] = 24,
34 [QCRYPTO_CIPHER_ALG_CAST5_128] = 16,
35 [QCRYPTO_CIPHER_ALG_SERPENT_128] = 16,
36 [QCRYPTO_CIPHER_ALG_SERPENT_192] = 24,
37 [QCRYPTO_CIPHER_ALG_SERPENT_256] = 32,
38 [QCRYPTO_CIPHER_ALG_TWOFISH_128] = 16,
39 [QCRYPTO_CIPHER_ALG_TWOFISH_192] = 24,
40 [QCRYPTO_CIPHER_ALG_TWOFISH_256] = 32,
41 #ifdef CONFIG_CRYPTO_SM4
42 [QCRYPTO_CIPHER_ALG_SM4] = 16,
43 #endif
44 };
45
46 static const size_t alg_block_len[QCRYPTO_CIPHER_ALG__MAX] = {
47 [QCRYPTO_CIPHER_ALG_AES_128] = 16,
48 [QCRYPTO_CIPHER_ALG_AES_192] = 16,
49 [QCRYPTO_CIPHER_ALG_AES_256] = 16,
50 [QCRYPTO_CIPHER_ALG_DES] = 8,
51 [QCRYPTO_CIPHER_ALG_3DES] = 8,
52 [QCRYPTO_CIPHER_ALG_CAST5_128] = 8,
53 [QCRYPTO_CIPHER_ALG_SERPENT_128] = 16,
54 [QCRYPTO_CIPHER_ALG_SERPENT_192] = 16,
55 [QCRYPTO_CIPHER_ALG_SERPENT_256] = 16,
56 [QCRYPTO_CIPHER_ALG_TWOFISH_128] = 16,
57 [QCRYPTO_CIPHER_ALG_TWOFISH_192] = 16,
58 [QCRYPTO_CIPHER_ALG_TWOFISH_256] = 16,
59 #ifdef CONFIG_CRYPTO_SM4
60 [QCRYPTO_CIPHER_ALG_SM4] = 16,
61 #endif
62 };
63
64 static const bool mode_need_iv[QCRYPTO_CIPHER_MODE__MAX] = {
65 [QCRYPTO_CIPHER_MODE_ECB] = false,
66 [QCRYPTO_CIPHER_MODE_CBC] = true,
67 [QCRYPTO_CIPHER_MODE_XTS] = true,
68 [QCRYPTO_CIPHER_MODE_CTR] = true,
69 };
70
71
qcrypto_cipher_get_block_len(QCryptoCipherAlgorithm alg)72 size_t qcrypto_cipher_get_block_len(QCryptoCipherAlgorithm alg)
73 {
74 assert(alg < G_N_ELEMENTS(alg_key_len));
75 return alg_block_len[alg];
76 }
77
78
qcrypto_cipher_get_key_len(QCryptoCipherAlgorithm alg)79 size_t qcrypto_cipher_get_key_len(QCryptoCipherAlgorithm alg)
80 {
81 assert(alg < G_N_ELEMENTS(alg_key_len));
82 return alg_key_len[alg];
83 }
84
85
qcrypto_cipher_get_iv_len(QCryptoCipherAlgorithm alg,QCryptoCipherMode mode)86 size_t qcrypto_cipher_get_iv_len(QCryptoCipherAlgorithm alg,
87 QCryptoCipherMode mode)
88 {
89 if (alg >= G_N_ELEMENTS(alg_block_len)) {
90 return 0;
91 }
92 if (mode >= G_N_ELEMENTS(mode_need_iv)) {
93 return 0;
94 }
95
96 if (mode_need_iv[mode]) {
97 return alg_block_len[alg];
98 }
99 return 0;
100 }
101
102
103 static bool
qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,QCryptoCipherMode mode,size_t nkey,Error ** errp)104 qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,
105 QCryptoCipherMode mode,
106 size_t nkey,
107 Error **errp)
108 {
109 if ((unsigned)alg >= QCRYPTO_CIPHER_ALG__MAX) {
110 error_setg(errp, "Cipher algorithm %d out of range",
111 alg);
112 return false;
113 }
114
115 if (mode == QCRYPTO_CIPHER_MODE_XTS) {
116 if (alg == QCRYPTO_CIPHER_ALG_DES ||
117 alg == QCRYPTO_CIPHER_ALG_3DES) {
118 error_setg(errp, "XTS mode not compatible with DES/3DES");
119 return false;
120 }
121 if (nkey % 2) {
122 error_setg(errp, "XTS cipher key length should be a multiple of 2");
123 return false;
124 }
125
126 if (alg_key_len[alg] != (nkey / 2)) {
127 error_setg(errp, "Cipher key length %zu should be %zu",
128 nkey, alg_key_len[alg] * 2);
129 return false;
130 }
131 } else {
132 if (alg_key_len[alg] != nkey) {
133 error_setg(errp, "Cipher key length %zu should be %zu",
134 nkey, alg_key_len[alg]);
135 return false;
136 }
137 }
138 return true;
139 }
140
141 #ifdef CONFIG_GCRYPT
142 #include "cipher-gcrypt.c.inc"
143 #elif defined CONFIG_NETTLE
144 #include "cipher-nettle.c.inc"
145 #elif defined CONFIG_GNUTLS_CRYPTO
146 #include "cipher-gnutls.c.inc"
147 #else
148 #include "cipher-builtin.c.inc"
149 #endif
150
qcrypto_cipher_new(QCryptoCipherAlgorithm alg,QCryptoCipherMode mode,const uint8_t * key,size_t nkey,Error ** errp)151 QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
152 QCryptoCipherMode mode,
153 const uint8_t *key, size_t nkey,
154 Error **errp)
155 {
156 QCryptoCipher *cipher = NULL;
157
158 #ifdef CONFIG_AF_ALG
159 cipher = qcrypto_afalg_cipher_ctx_new(alg, mode, key, nkey, NULL);
160 #endif
161
162 if (!cipher) {
163 cipher = qcrypto_cipher_ctx_new(alg, mode, key, nkey, errp);
164 if (!cipher) {
165 return NULL;
166 }
167 }
168
169 cipher->alg = alg;
170 cipher->mode = mode;
171
172 return cipher;
173 }
174
175
qcrypto_cipher_encrypt(QCryptoCipher * cipher,const void * in,void * out,size_t len,Error ** errp)176 int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
177 const void *in,
178 void *out,
179 size_t len,
180 Error **errp)
181 {
182 const QCryptoCipherDriver *drv = cipher->driver;
183 return drv->cipher_encrypt(cipher, in, out, len, errp);
184 }
185
186
qcrypto_cipher_decrypt(QCryptoCipher * cipher,const void * in,void * out,size_t len,Error ** errp)187 int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
188 const void *in,
189 void *out,
190 size_t len,
191 Error **errp)
192 {
193 const QCryptoCipherDriver *drv = cipher->driver;
194 return drv->cipher_decrypt(cipher, in, out, len, errp);
195 }
196
197
qcrypto_cipher_setiv(QCryptoCipher * cipher,const uint8_t * iv,size_t niv,Error ** errp)198 int qcrypto_cipher_setiv(QCryptoCipher *cipher,
199 const uint8_t *iv, size_t niv,
200 Error **errp)
201 {
202 const QCryptoCipherDriver *drv = cipher->driver;
203 return drv->cipher_setiv(cipher, iv, niv, errp);
204 }
205
206
qcrypto_cipher_free(QCryptoCipher * cipher)207 void qcrypto_cipher_free(QCryptoCipher *cipher)
208 {
209 if (cipher) {
210 cipher->driver->cipher_free(cipher);
211 }
212 }
213