diff options
Diffstat (limited to 'crypto/cipher-gcrypt.c')
| -rw-r--r-- | crypto/cipher-gcrypt.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/crypto/cipher-gcrypt.c b/crypto/cipher-gcrypt.c new file mode 100644 index 0000000000..8cfc562500 --- /dev/null +++ b/crypto/cipher-gcrypt.c @@ -0,0 +1,195 @@ +/* + * QEMU Crypto cipher libgcrypt algorithms + * + * Copyright (c) 2015 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + * + */ + +#include <gcrypt.h> + + +bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg) +{ + switch (alg) { + case QCRYPTO_CIPHER_ALG_DES_RFB: + case QCRYPTO_CIPHER_ALG_AES_128: + case QCRYPTO_CIPHER_ALG_AES_192: + case QCRYPTO_CIPHER_ALG_AES_256: + return true; + default: + return false; + } +} + + +QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg, + QCryptoCipherMode mode, + const uint8_t *key, size_t nkey, + Error **errp) +{ + QCryptoCipher *cipher; + gcry_cipher_hd_t handle; + gcry_error_t err; + int gcryalg, gcrymode; + + switch (mode) { + case QCRYPTO_CIPHER_MODE_ECB: + gcrymode = GCRY_CIPHER_MODE_ECB; + break; + case QCRYPTO_CIPHER_MODE_CBC: + gcrymode = GCRY_CIPHER_MODE_CBC; + break; + default: + error_setg(errp, "Unsupported cipher mode %d", mode); + return NULL; + } + + if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) { + return NULL; + } + + switch (alg) { + case QCRYPTO_CIPHER_ALG_DES_RFB: + gcryalg = GCRY_CIPHER_DES; + break; + + case QCRYPTO_CIPHER_ALG_AES_128: + gcryalg = GCRY_CIPHER_AES128; + break; + + case QCRYPTO_CIPHER_ALG_AES_192: + gcryalg = GCRY_CIPHER_AES192; + break; + + case QCRYPTO_CIPHER_ALG_AES_256: + gcryalg = GCRY_CIPHER_AES256; + break; + + default: + error_setg(errp, "Unsupported cipher algorithm %d", alg); + return NULL; + } + + cipher = g_new0(QCryptoCipher, 1); + cipher->alg = alg; + cipher->mode = mode; + + err = gcry_cipher_open(&handle, gcryalg, gcrymode, 0); + if (err != 0) { + error_setg(errp, "Cannot initialize cipher: %s", + gcry_strerror(err)); + goto error; + } + + if (cipher->alg == QCRYPTO_CIPHER_ALG_DES_RFB) { + /* We're using standard DES cipher from gcrypt, so we need + * to munge the key so that the results are the same as the + * bizarre RFB variant of DES :-) + */ + uint8_t *rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey); + err = gcry_cipher_setkey(handle, rfbkey, nkey); + g_free(rfbkey); + } else { + err = gcry_cipher_setkey(handle, key, nkey); + } + if (err != 0) { + error_setg(errp, "Cannot set key: %s", + gcry_strerror(err)); + goto error; + } + + cipher->opaque = handle; + return cipher; + + error: + gcry_cipher_close(handle); + g_free(cipher); + return NULL; +} + + +void qcrypto_cipher_free(QCryptoCipher *cipher) +{ + gcry_cipher_hd_t handle; + if (!cipher) { + return; + } + handle = cipher->opaque; + gcry_cipher_close(handle); + g_free(cipher); +} + + +int qcrypto_cipher_encrypt(QCryptoCipher *cipher, + const void *in, + void *out, + size_t len, + Error **errp) +{ + gcry_cipher_hd_t handle = cipher->opaque; + gcry_error_t err; + + err = gcry_cipher_encrypt(handle, + out, len, + in, len); + if (err != 0) { + error_setg(errp, "Cannot encrypt data: %s", + gcry_strerror(err)); + return -1; + } + + return 0; +} + + +int qcrypto_cipher_decrypt(QCryptoCipher *cipher, + const void *in, + void *out, + size_t len, + Error **errp) +{ + gcry_cipher_hd_t handle = cipher->opaque; + gcry_error_t err; + + err = gcry_cipher_decrypt(handle, + out, len, + in, len); + if (err != 0) { + error_setg(errp, "Cannot decrypt data: %s", + gcry_strerror(err)); + return -1; + } + + return 0; +} + +int qcrypto_cipher_setiv(QCryptoCipher *cipher, + const uint8_t *iv, size_t niv, + Error **errp) +{ + gcry_cipher_hd_t handle = cipher->opaque; + gcry_error_t err; + + gcry_cipher_reset(handle); + err = gcry_cipher_setiv(handle, iv, niv); + if (err != 0) { + error_setg(errp, "Cannot set IV: %s", + gcry_strerror(err)); + return -1; + } + + return 0; +} |