summaryrefslogtreecommitdiffstats
path: root/src/crypto/cipher-gcrypt.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/crypto/cipher-gcrypt.c')
-rw-r--r--src/crypto/cipher-gcrypt.c224
1 files changed, 224 insertions, 0 deletions
diff --git a/src/crypto/cipher-gcrypt.c b/src/crypto/cipher-gcrypt.c
new file mode 100644
index 0000000..c4f8114
--- /dev/null
+++ b/src/crypto/cipher-gcrypt.c
@@ -0,0 +1,224 @@
+/*
+ * 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;
+ }
+}
+
+typedef struct QCryptoCipherGcrypt QCryptoCipherGcrypt;
+struct QCryptoCipherGcrypt {
+ gcry_cipher_hd_t handle;
+ size_t blocksize;
+};
+
+QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
+ QCryptoCipherMode mode,
+ const uint8_t *key, size_t nkey,
+ Error **errp)
+{
+ QCryptoCipher *cipher;
+ QCryptoCipherGcrypt *ctx;
+ 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;
+
+ ctx = g_new0(QCryptoCipherGcrypt, 1);
+
+ err = gcry_cipher_open(&ctx->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(ctx->handle, rfbkey, nkey);
+ g_free(rfbkey);
+ ctx->blocksize = 8;
+ } else {
+ err = gcry_cipher_setkey(ctx->handle, key, nkey);
+ ctx->blocksize = 16;
+ }
+ if (err != 0) {
+ error_setg(errp, "Cannot set key: %s",
+ gcry_strerror(err));
+ goto error;
+ }
+
+ cipher->opaque = ctx;
+ return cipher;
+
+ error:
+ gcry_cipher_close(ctx->handle);
+ g_free(ctx);
+ g_free(cipher);
+ return NULL;
+}
+
+
+void qcrypto_cipher_free(QCryptoCipher *cipher)
+{
+ QCryptoCipherGcrypt *ctx;
+ if (!cipher) {
+ return;
+ }
+ ctx = cipher->opaque;
+ gcry_cipher_close(ctx->handle);
+ g_free(ctx);
+ g_free(cipher);
+}
+
+
+int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherGcrypt *ctx = cipher->opaque;
+ gcry_error_t err;
+
+ if (len % ctx->blocksize) {
+ error_setg(errp, "Length %zu must be a multiple of block size %zu",
+ len, ctx->blocksize);
+ return -1;
+ }
+
+ err = gcry_cipher_encrypt(ctx->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)
+{
+ QCryptoCipherGcrypt *ctx = cipher->opaque;
+ gcry_error_t err;
+
+ if (len % ctx->blocksize) {
+ error_setg(errp, "Length %zu must be a multiple of block size %zu",
+ len, ctx->blocksize);
+ return -1;
+ }
+
+ err = gcry_cipher_decrypt(ctx->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)
+{
+ QCryptoCipherGcrypt *ctx = cipher->opaque;
+ gcry_error_t err;
+
+ if (niv != ctx->blocksize) {
+ error_setg(errp, "Expected IV size %zu not %zu",
+ ctx->blocksize, niv);
+ return -1;
+ }
+
+ gcry_cipher_reset(ctx->handle);
+ err = gcry_cipher_setiv(ctx->handle, iv, niv);
+ if (err != 0) {
+ error_setg(errp, "Cannot set IV: %s",
+ gcry_strerror(err));
+ return -1;
+ }
+
+ return 0;
+}
OpenPOWER on IntegriCloud