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authorDaniel P. Berrange <berrange@redhat.com>2015-07-01 18:10:32 +0100
committerPaolo Bonzini <pbonzini@redhat.com>2015-07-08 13:11:01 +0200
commitca38a4cc9e36647437b837b346a41981fb8880cd (patch)
treebb29de3cad2138f694bbfb4485d0d989caacc759 /crypto/cipher-builtin.c
parent9fd72468dfe40532df7c64d35054994058106c42 (diff)
downloadqemu-ca38a4cc9e36647437b837b346a41981fb8880cd.tar.gz
crypto: introduce generic cipher API & built-in implementation
Introduce a generic cipher API and an implementation of it that supports only the built-in AES and DES-RFB algorithms. The test suite checks the supported algorithms + modes to validate that every backend implementation is actually correctly complying with the specs. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1435770638-25715-5-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'crypto/cipher-builtin.c')
-rw-r--r--crypto/cipher-builtin.c398
1 files changed, 398 insertions, 0 deletions
diff --git a/crypto/cipher-builtin.c b/crypto/cipher-builtin.c
new file mode 100644
index 0000000000..c625cb40f7
--- /dev/null
+++ b/crypto/cipher-builtin.c
@@ -0,0 +1,398 @@
+/*
+ * QEMU Crypto cipher built-in 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 "crypto/aes.h"
+#include "crypto/desrfb.h"
+
+typedef struct QCryptoCipherBuiltinAES QCryptoCipherBuiltinAES;
+struct QCryptoCipherBuiltinAES {
+ AES_KEY encrypt_key;
+ AES_KEY decrypt_key;
+ uint8_t *iv;
+ size_t niv;
+};
+typedef struct QCryptoCipherBuiltinDESRFB QCryptoCipherBuiltinDESRFB;
+struct QCryptoCipherBuiltinDESRFB {
+ uint8_t *key;
+ size_t nkey;
+};
+
+typedef struct QCryptoCipherBuiltin QCryptoCipherBuiltin;
+struct QCryptoCipherBuiltin {
+ union {
+ QCryptoCipherBuiltinAES aes;
+ QCryptoCipherBuiltinDESRFB desrfb;
+ } state;
+ void (*free)(QCryptoCipher *cipher);
+ int (*setiv)(QCryptoCipher *cipher,
+ const uint8_t *iv, size_t niv,
+ Error **errp);
+ int (*encrypt)(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp);
+ int (*decrypt)(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp);
+};
+
+
+static void qcrypto_cipher_free_aes(QCryptoCipher *cipher)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ g_free(ctxt->state.aes.iv);
+ g_free(ctxt);
+ cipher->opaque = NULL;
+}
+
+
+static int qcrypto_cipher_encrypt_aes(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ if (cipher->mode == QCRYPTO_CIPHER_MODE_ECB) {
+ const uint8_t *inptr = in;
+ uint8_t *outptr = out;
+ while (len) {
+ if (len > AES_BLOCK_SIZE) {
+ AES_encrypt(inptr, outptr, &ctxt->state.aes.encrypt_key);
+ inptr += AES_BLOCK_SIZE;
+ outptr += AES_BLOCK_SIZE;
+ len -= AES_BLOCK_SIZE;
+ } else {
+ uint8_t tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
+ memcpy(tmp1, inptr, len);
+ /* Fill with 0 to avoid valgrind uninitialized reads */
+ memset(tmp1 + len, 0, sizeof(tmp1) - len);
+ AES_encrypt(tmp1, tmp2, &ctxt->state.aes.encrypt_key);
+ memcpy(outptr, tmp2, len);
+ len = 0;
+ }
+ }
+ } else {
+ AES_cbc_encrypt(in, out, len,
+ &ctxt->state.aes.encrypt_key,
+ ctxt->state.aes.iv, 1);
+ }
+
+ return 0;
+}
+
+
+static int qcrypto_cipher_decrypt_aes(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ if (cipher->mode == QCRYPTO_CIPHER_MODE_ECB) {
+ const uint8_t *inptr = in;
+ uint8_t *outptr = out;
+ while (len) {
+ if (len > AES_BLOCK_SIZE) {
+ AES_decrypt(inptr, outptr, &ctxt->state.aes.encrypt_key);
+ inptr += AES_BLOCK_SIZE;
+ outptr += AES_BLOCK_SIZE;
+ len -= AES_BLOCK_SIZE;
+ } else {
+ uint8_t tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
+ memcpy(tmp1, inptr, len);
+ /* Fill with 0 to avoid valgrind uninitialized reads */
+ memset(tmp1 + len, 0, sizeof(tmp1) - len);
+ AES_decrypt(tmp1, tmp2, &ctxt->state.aes.encrypt_key);
+ memcpy(outptr, tmp2, len);
+ len = 0;
+ }
+ }
+ } else {
+ AES_cbc_encrypt(in, out, len,
+ &ctxt->state.aes.encrypt_key,
+ ctxt->state.aes.iv, 1);
+ }
+
+ return 0;
+}
+
+static int qcrypto_cipher_setiv_aes(QCryptoCipher *cipher,
+ const uint8_t *iv, size_t niv,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+ if (niv != 16) {
+ error_setg(errp, "IV must be 16 bytes not %zu", niv);
+ return -1;
+ }
+
+ g_free(ctxt->state.aes.iv);
+ ctxt->state.aes.iv = g_new0(uint8_t, niv);
+ memcpy(ctxt->state.aes.iv, iv, niv);
+ ctxt->state.aes.niv = niv;
+
+ return 0;
+}
+
+
+
+
+static int qcrypto_cipher_init_aes(QCryptoCipher *cipher,
+ const uint8_t *key, size_t nkey,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt;
+
+ if (cipher->mode != QCRYPTO_CIPHER_MODE_CBC &&
+ cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
+ error_setg(errp, "Unsupported cipher mode %d", cipher->mode);
+ return -1;
+ }
+
+ ctxt = g_new0(QCryptoCipherBuiltin, 1);
+
+ if (AES_set_encrypt_key(key, nkey * 8, &ctxt->state.aes.encrypt_key) != 0) {
+ error_setg(errp, "Failed to set encryption key");
+ goto error;
+ }
+
+ if (AES_set_decrypt_key(key, nkey * 8, &ctxt->state.aes.decrypt_key) != 0) {
+ error_setg(errp, "Failed to set decryption key");
+ goto error;
+ }
+
+ ctxt->free = qcrypto_cipher_free_aes;
+ ctxt->setiv = qcrypto_cipher_setiv_aes;
+ ctxt->encrypt = qcrypto_cipher_encrypt_aes;
+ ctxt->decrypt = qcrypto_cipher_decrypt_aes;
+
+ cipher->opaque = ctxt;
+
+ return 0;
+
+ error:
+ g_free(ctxt);
+ return -1;
+}
+
+
+static void qcrypto_cipher_free_des_rfb(QCryptoCipher *cipher)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ g_free(ctxt->state.desrfb.key);
+ g_free(ctxt);
+ cipher->opaque = NULL;
+}
+
+
+static int qcrypto_cipher_encrypt_des_rfb(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+ size_t i;
+
+ if (len % 8) {
+ error_setg(errp, "Buffer size must be multiple of 8 not %zu",
+ len);
+ return -1;
+ }
+
+ deskey(ctxt->state.desrfb.key, EN0);
+
+ for (i = 0; i < len; i += 8) {
+ des((void *)in + i, out + i);
+ }
+
+ return 0;
+}
+
+
+static int qcrypto_cipher_decrypt_des_rfb(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+ size_t i;
+
+ if (len % 8) {
+ error_setg(errp, "Buffer size must be multiple of 8 not %zu",
+ len);
+ return -1;
+ }
+
+ deskey(ctxt->state.desrfb.key, DE1);
+
+ for (i = 0; i < len; i += 8) {
+ des((void *)in + i, out + i);
+ }
+
+ return 0;
+}
+
+
+static int qcrypto_cipher_setiv_des_rfb(QCryptoCipher *cipher,
+ const uint8_t *iv, size_t niv,
+ Error **errp)
+{
+ error_setg(errp, "Setting IV is not supported");
+ return -1;
+}
+
+
+static int qcrypto_cipher_init_des_rfb(QCryptoCipher *cipher,
+ const uint8_t *key, size_t nkey,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt;
+
+ if (cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
+ error_setg(errp, "Unsupported cipher mode %d", cipher->mode);
+ return -1;
+ }
+
+ ctxt = g_new0(QCryptoCipherBuiltin, 1);
+
+ ctxt->state.desrfb.key = g_new0(uint8_t, nkey);
+ memcpy(ctxt->state.desrfb.key, key, nkey);
+ ctxt->state.desrfb.nkey = nkey;
+
+ ctxt->free = qcrypto_cipher_free_des_rfb;
+ ctxt->setiv = qcrypto_cipher_setiv_des_rfb;
+ ctxt->encrypt = qcrypto_cipher_encrypt_des_rfb;
+ ctxt->decrypt = qcrypto_cipher_decrypt_des_rfb;
+
+ cipher->opaque = ctxt;
+
+ return 0;
+}
+
+
+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;
+
+ cipher = g_new0(QCryptoCipher, 1);
+ cipher->alg = alg;
+ cipher->mode = mode;
+
+ if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) {
+ goto error;
+ }
+
+ switch (cipher->alg) {
+ case QCRYPTO_CIPHER_ALG_DES_RFB:
+ if (qcrypto_cipher_init_des_rfb(cipher, key, nkey, errp) < 0) {
+ goto error;
+ }
+ break;
+ case QCRYPTO_CIPHER_ALG_AES_128:
+ case QCRYPTO_CIPHER_ALG_AES_192:
+ case QCRYPTO_CIPHER_ALG_AES_256:
+ if (qcrypto_cipher_init_aes(cipher, key, nkey, errp) < 0) {
+ goto error;
+ }
+ break;
+ default:
+ error_setg(errp,
+ "Unsupported cipher algorithm %d", cipher->alg);
+ goto error;
+ }
+
+ return cipher;
+
+ error:
+ g_free(cipher);
+ return NULL;
+}
+
+void qcrypto_cipher_free(QCryptoCipher *cipher)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+ if (!cipher) {
+ return;
+ }
+
+ ctxt->free(cipher);
+ g_free(cipher);
+}
+
+
+int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ return ctxt->encrypt(cipher, in, out, len, errp);
+}
+
+
+int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
+ const void *in,
+ void *out,
+ size_t len,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ return ctxt->decrypt(cipher, in, out, len, errp);
+}
+
+
+int qcrypto_cipher_setiv(QCryptoCipher *cipher,
+ const uint8_t *iv, size_t niv,
+ Error **errp)
+{
+ QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+ return ctxt->setiv(cipher, iv, niv, errp);
+}