2 * QEMU Crypto cipher libgcrypt algorithms
4 * Copyright (c) 2015 Red Hat, Inc.
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 of the License, or (at your option) any later version.
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.
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/>.
21 #include "qemu/osdep.h"
22 #include "crypto/xts.h"
27 bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg
,
28 QCryptoCipherMode mode
)
31 case QCRYPTO_CIPHER_ALG_DES_RFB
:
32 case QCRYPTO_CIPHER_ALG_3DES
:
33 case QCRYPTO_CIPHER_ALG_AES_128
:
34 case QCRYPTO_CIPHER_ALG_AES_192
:
35 case QCRYPTO_CIPHER_ALG_AES_256
:
36 case QCRYPTO_CIPHER_ALG_CAST5_128
:
37 case QCRYPTO_CIPHER_ALG_SERPENT_128
:
38 case QCRYPTO_CIPHER_ALG_SERPENT_192
:
39 case QCRYPTO_CIPHER_ALG_SERPENT_256
:
40 case QCRYPTO_CIPHER_ALG_TWOFISH_128
:
41 case QCRYPTO_CIPHER_ALG_TWOFISH_256
:
48 case QCRYPTO_CIPHER_MODE_ECB
:
49 case QCRYPTO_CIPHER_MODE_CBC
:
50 case QCRYPTO_CIPHER_MODE_XTS
:
51 case QCRYPTO_CIPHER_MODE_CTR
:
58 typedef struct QCryptoCipherGcrypt QCryptoCipherGcrypt
;
59 struct QCryptoCipherGcrypt
{
60 gcry_cipher_hd_t handle
;
61 gcry_cipher_hd_t tweakhandle
;
63 /* Initialization vector or Counter */
67 static void gcrypt_cipher_free_ctx(QCryptoCipherGcrypt
*ctx
,
68 QCryptoCipherMode mode
)
74 gcry_cipher_close(ctx
->handle
);
75 if (mode
== QCRYPTO_CIPHER_MODE_XTS
) {
76 gcry_cipher_close(ctx
->tweakhandle
);
83 static QCryptoCipherGcrypt
*qcrypto_cipher_ctx_new(QCryptoCipherAlgorithm alg
,
84 QCryptoCipherMode mode
,
89 QCryptoCipherGcrypt
*ctx
;
91 int gcryalg
, gcrymode
;
94 case QCRYPTO_CIPHER_MODE_ECB
:
95 case QCRYPTO_CIPHER_MODE_XTS
:
96 gcrymode
= GCRY_CIPHER_MODE_ECB
;
98 case QCRYPTO_CIPHER_MODE_CBC
:
99 gcrymode
= GCRY_CIPHER_MODE_CBC
;
101 case QCRYPTO_CIPHER_MODE_CTR
:
102 gcrymode
= GCRY_CIPHER_MODE_CTR
;
105 error_setg(errp
, "Unsupported cipher mode %s",
106 QCryptoCipherMode_lookup
[mode
]);
110 if (!qcrypto_cipher_validate_key_length(alg
, mode
, nkey
, errp
)) {
115 case QCRYPTO_CIPHER_ALG_DES_RFB
:
116 gcryalg
= GCRY_CIPHER_DES
;
119 case QCRYPTO_CIPHER_ALG_3DES
:
120 gcryalg
= GCRY_CIPHER_3DES
;
123 case QCRYPTO_CIPHER_ALG_AES_128
:
124 gcryalg
= GCRY_CIPHER_AES128
;
127 case QCRYPTO_CIPHER_ALG_AES_192
:
128 gcryalg
= GCRY_CIPHER_AES192
;
131 case QCRYPTO_CIPHER_ALG_AES_256
:
132 gcryalg
= GCRY_CIPHER_AES256
;
135 case QCRYPTO_CIPHER_ALG_CAST5_128
:
136 gcryalg
= GCRY_CIPHER_CAST5
;
139 case QCRYPTO_CIPHER_ALG_SERPENT_128
:
140 gcryalg
= GCRY_CIPHER_SERPENT128
;
143 case QCRYPTO_CIPHER_ALG_SERPENT_192
:
144 gcryalg
= GCRY_CIPHER_SERPENT192
;
147 case QCRYPTO_CIPHER_ALG_SERPENT_256
:
148 gcryalg
= GCRY_CIPHER_SERPENT256
;
151 case QCRYPTO_CIPHER_ALG_TWOFISH_128
:
152 gcryalg
= GCRY_CIPHER_TWOFISH128
;
155 case QCRYPTO_CIPHER_ALG_TWOFISH_256
:
156 gcryalg
= GCRY_CIPHER_TWOFISH
;
160 error_setg(errp
, "Unsupported cipher algorithm %s",
161 QCryptoCipherAlgorithm_lookup
[alg
]);
165 ctx
= g_new0(QCryptoCipherGcrypt
, 1);
167 err
= gcry_cipher_open(&ctx
->handle
, gcryalg
, gcrymode
, 0);
169 error_setg(errp
, "Cannot initialize cipher: %s",
173 if (mode
== QCRYPTO_CIPHER_MODE_XTS
) {
174 err
= gcry_cipher_open(&ctx
->tweakhandle
, gcryalg
, gcrymode
, 0);
176 error_setg(errp
, "Cannot initialize cipher: %s",
182 if (alg
== QCRYPTO_CIPHER_ALG_DES_RFB
) {
183 /* We're using standard DES cipher from gcrypt, so we need
184 * to munge the key so that the results are the same as the
185 * bizarre RFB variant of DES :-)
187 uint8_t *rfbkey
= qcrypto_cipher_munge_des_rfb_key(key
, nkey
);
188 err
= gcry_cipher_setkey(ctx
->handle
, rfbkey
, nkey
);
192 if (mode
== QCRYPTO_CIPHER_MODE_XTS
) {
194 err
= gcry_cipher_setkey(ctx
->handle
, key
, nkey
);
196 error_setg(errp
, "Cannot set key: %s",
200 err
= gcry_cipher_setkey(ctx
->tweakhandle
, key
+ nkey
, nkey
);
202 err
= gcry_cipher_setkey(ctx
->handle
, key
, nkey
);
205 error_setg(errp
, "Cannot set key: %s",
210 case QCRYPTO_CIPHER_ALG_AES_128
:
211 case QCRYPTO_CIPHER_ALG_AES_192
:
212 case QCRYPTO_CIPHER_ALG_AES_256
:
213 case QCRYPTO_CIPHER_ALG_SERPENT_128
:
214 case QCRYPTO_CIPHER_ALG_SERPENT_192
:
215 case QCRYPTO_CIPHER_ALG_SERPENT_256
:
216 case QCRYPTO_CIPHER_ALG_TWOFISH_128
:
217 case QCRYPTO_CIPHER_ALG_TWOFISH_256
:
220 case QCRYPTO_CIPHER_ALG_3DES
:
221 case QCRYPTO_CIPHER_ALG_CAST5_128
:
225 g_assert_not_reached();
229 if (mode
== QCRYPTO_CIPHER_MODE_XTS
) {
230 if (ctx
->blocksize
!= XTS_BLOCK_SIZE
) {
232 "Cipher block size %zu must equal XTS block size %d",
233 ctx
->blocksize
, XTS_BLOCK_SIZE
);
236 ctx
->iv
= g_new0(uint8_t, ctx
->blocksize
);
242 gcrypt_cipher_free_ctx(ctx
, mode
);
247 void qcrypto_cipher_free(QCryptoCipher
*cipher
)
252 gcrypt_cipher_free_ctx(cipher
->opaque
, cipher
->mode
);
257 static void qcrypto_gcrypt_xts_encrypt(const void *ctx
,
263 err
= gcry_cipher_encrypt((gcry_cipher_hd_t
)ctx
, dst
, length
, src
, length
);
267 static void qcrypto_gcrypt_xts_decrypt(const void *ctx
,
273 err
= gcry_cipher_decrypt((gcry_cipher_hd_t
)ctx
, dst
, length
, src
, length
);
277 int qcrypto_cipher_encrypt(QCryptoCipher
*cipher
,
283 QCryptoCipherGcrypt
*ctx
= cipher
->opaque
;
286 if (len
% ctx
->blocksize
) {
287 error_setg(errp
, "Length %zu must be a multiple of block size %zu",
288 len
, ctx
->blocksize
);
292 if (cipher
->mode
== QCRYPTO_CIPHER_MODE_XTS
) {
293 xts_encrypt(ctx
->handle
, ctx
->tweakhandle
,
294 qcrypto_gcrypt_xts_encrypt
,
295 qcrypto_gcrypt_xts_decrypt
,
296 ctx
->iv
, len
, out
, in
);
298 err
= gcry_cipher_encrypt(ctx
->handle
,
302 error_setg(errp
, "Cannot encrypt data: %s",
312 int qcrypto_cipher_decrypt(QCryptoCipher
*cipher
,
318 QCryptoCipherGcrypt
*ctx
= cipher
->opaque
;
321 if (len
% ctx
->blocksize
) {
322 error_setg(errp
, "Length %zu must be a multiple of block size %zu",
323 len
, ctx
->blocksize
);
327 if (cipher
->mode
== QCRYPTO_CIPHER_MODE_XTS
) {
328 xts_decrypt(ctx
->handle
, ctx
->tweakhandle
,
329 qcrypto_gcrypt_xts_encrypt
,
330 qcrypto_gcrypt_xts_decrypt
,
331 ctx
->iv
, len
, out
, in
);
333 err
= gcry_cipher_decrypt(ctx
->handle
,
337 error_setg(errp
, "Cannot decrypt data: %s",
346 int qcrypto_cipher_setiv(QCryptoCipher
*cipher
,
347 const uint8_t *iv
, size_t niv
,
350 QCryptoCipherGcrypt
*ctx
= cipher
->opaque
;
353 if (niv
!= ctx
->blocksize
) {
354 error_setg(errp
, "Expected IV size %zu not %zu",
355 ctx
->blocksize
, niv
);
360 memcpy(ctx
->iv
, iv
, niv
);
362 if (cipher
->mode
== QCRYPTO_CIPHER_MODE_CTR
) {
363 err
= gcry_cipher_setctr(ctx
->handle
, iv
, niv
);
365 error_setg(errp
, "Cannot set Counter: %s",
370 gcry_cipher_reset(ctx
->handle
);
371 err
= gcry_cipher_setiv(ctx
->handle
, iv
, niv
);
373 error_setg(errp
, "Cannot set IV: %s",
384 QCryptoCipher
*qcrypto_cipher_new(QCryptoCipherAlgorithm alg
,
385 QCryptoCipherMode mode
,
386 const uint8_t *key
, size_t nkey
,
389 QCryptoCipher
*cipher
;
390 QCryptoCipherGcrypt
*ctx
;
392 ctx
= qcrypto_cipher_ctx_new(alg
, mode
, key
, nkey
, errp
);
397 cipher
= g_new0(QCryptoCipher
, 1);
400 cipher
->opaque
= ctx
;