--- /dev/null
+/*
+ * QEMU Crypto cipher nettle 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 <nettle/nettle-types.h>
+#include <nettle/aes.h>
+#include <nettle/des.h>
+#include <nettle/cbc.h>
+
+#if CONFIG_NETTLE_VERSION_MAJOR < 3
+typedef nettle_crypt_func nettle_cipher_func;
+
+typedef void * cipher_ctx_t;
+typedef unsigned cipher_length_t;
+#else
+typedef const void * cipher_ctx_t;
+typedef size_t cipher_length_t;
+#endif
+
+static nettle_cipher_func aes_encrypt_wrapper;
+static nettle_cipher_func aes_decrypt_wrapper;
+static nettle_cipher_func des_encrypt_wrapper;
+static nettle_cipher_func des_decrypt_wrapper;
+
+static void aes_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
+ uint8_t *dst, const uint8_t *src)
+{
+ aes_encrypt(ctx, length, dst, src);
+}
+
+static void aes_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
+ uint8_t *dst, const uint8_t *src)
+{
+ aes_decrypt(ctx, length, dst, src);
+}
+
+static void des_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
+ uint8_t *dst, const uint8_t *src)
+{
+ des_encrypt(ctx, length, dst, src);
+}
+
+static void des_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
+ uint8_t *dst, const uint8_t *src)
+{
+ des_decrypt(ctx, length, dst, src);
+}
+
+typedef struct QCryptoCipherNettle QCryptoCipherNettle;
+struct QCryptoCipherNettle {
+ void *ctx_encrypt;
+ void *ctx_decrypt;
+ nettle_cipher_func *alg_encrypt;
+ nettle_cipher_func *alg_decrypt;
+ uint8_t *iv;
+ size_t niv;
+};
+
+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;
+ QCryptoCipherNettle *ctx;
+ uint8_t *rfbkey;
+
+ switch (mode) {
+ case QCRYPTO_CIPHER_MODE_ECB:
+ case QCRYPTO_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;
+ }
+
+ cipher = g_new0(QCryptoCipher, 1);
+ cipher->alg = alg;
+ cipher->mode = mode;
+
+ ctx = g_new0(QCryptoCipherNettle, 1);
+
+ switch (alg) {
+ case QCRYPTO_CIPHER_ALG_DES_RFB:
+ ctx->ctx_encrypt = g_new0(struct des_ctx, 1);
+ ctx->ctx_decrypt = NULL; /* 1 ctx can do both */
+ rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
+ des_set_key(ctx->ctx_encrypt, rfbkey);
+ g_free(rfbkey);
+
+ ctx->alg_encrypt = des_encrypt_wrapper;
+ ctx->alg_decrypt = des_decrypt_wrapper;
+
+ ctx->niv = DES_BLOCK_SIZE;
+ break;
+
+ case QCRYPTO_CIPHER_ALG_AES_128:
+ case QCRYPTO_CIPHER_ALG_AES_192:
+ case QCRYPTO_CIPHER_ALG_AES_256:
+ ctx->ctx_encrypt = g_new0(struct aes_ctx, 1);
+ ctx->ctx_decrypt = g_new0(struct aes_ctx, 1);
+
+ aes_set_encrypt_key(ctx->ctx_encrypt, nkey, key);
+ aes_set_decrypt_key(ctx->ctx_decrypt, nkey, key);
+
+ ctx->alg_encrypt = aes_encrypt_wrapper;
+ ctx->alg_decrypt = aes_decrypt_wrapper;
+
+ ctx->niv = AES_BLOCK_SIZE;
+ break;
+ default:
+ error_setg(errp, "Unsupported cipher algorithm %d", alg);
+ goto error;
+ }
+
+ ctx->iv = g_new0(uint8_t, ctx->niv);
+ cipher->opaque = ctx;
+
+ return cipher;
+
+ error:
+ g_free(cipher);
+ g_free(ctx);
+ return NULL;
+}
+
+
+void qcrypto_cipher_free(QCryptoCipher *cipher)
+{
+ QCryptoCipherNettle *ctx;
+
+ if (!cipher) {
+ return;
+ }
+
+ ctx = cipher->opaque;
+ g_free(ctx->iv);
+ g_free(ctx->ctx_encrypt);
+ g_free(ctx->ctx_decrypt);
+ g_free(ctx);
+ g_free(cipher);
+}
+
+
+int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherNettle *ctx = cipher->opaque;
+
+ switch (cipher->mode) {
+ case QCRYPTO_CIPHER_MODE_ECB:
+ ctx->alg_encrypt(ctx->ctx_encrypt, len, out, in);
+ break;
+
+ case QCRYPTO_CIPHER_MODE_CBC:
+ cbc_encrypt(ctx->ctx_encrypt, ctx->alg_encrypt,
+ ctx->niv, ctx->iv,
+ len, out, in);
+ break;
+ default:
+ error_setg(errp, "Unsupported cipher algorithm %d",
+ cipher->alg);
+ return -1;
+ }
+ return 0;
+}
+
+
+int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherNettle *ctx = cipher->opaque;
+
+ switch (cipher->mode) {
+ case QCRYPTO_CIPHER_MODE_ECB:
+ ctx->alg_decrypt(ctx->ctx_decrypt ? ctx->ctx_decrypt : ctx->ctx_encrypt,
+ len, out, in);
+ break;
+
+ case QCRYPTO_CIPHER_MODE_CBC:
+ cbc_decrypt(ctx->ctx_decrypt ? ctx->ctx_decrypt : ctx->ctx_encrypt,
+ ctx->alg_decrypt, ctx->niv, ctx->iv,
+ len, out, in);
+ break;
+ default:
+ error_setg(errp, "Unsupported cipher algorithm %d",
+ cipher->alg);
+ return -1;
+ }
+ return 0;
+}
+
+int qcrypto_cipher_setiv(QCryptoCipher *cipher,
+ const uint8_t *iv, size_t niv,
+ Error **errp)
+{
+ QCryptoCipherNettle *ctx = cipher->opaque;
+ if (niv != ctx->niv) {
+ error_setg(errp, "Expected IV size %zu not %zu",
+ ctx->niv, niv);
+ return -1;
+ }
+ memcpy(ctx->iv, iv, niv);
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff