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authorDon Dugger <n0ano@n0ano.com>2016-06-03 03:33:22 +0000
committerGerrit Code Review <gerrit@172.30.200.206>2016-06-03 03:33:23 +0000
commitda27230f80795d0028333713f036d44c53cb0e68 (patch)
treeb3d379eaf000adf72b36cb01cdf4d79c3e3f064c /qemu/crypto/afsplit.c
parent0e68cb048bb8aadb14675f5d4286d8ab2fc35449 (diff)
parent437fd90c0250dee670290f9b714253671a990160 (diff)
Merge "These changes are the raw update to qemu-2.6."
Diffstat (limited to 'qemu/crypto/afsplit.c')
-rw-r--r--qemu/crypto/afsplit.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/qemu/crypto/afsplit.c b/qemu/crypto/afsplit.c
new file mode 100644
index 000000000..8074913cd
--- /dev/null
+++ b/qemu/crypto/afsplit.c
@@ -0,0 +1,158 @@
+/*
+ * QEMU Crypto anti forensic information splitter
+ *
+ * Copyright (c) 2015-2016 Red Hat, Inc.
+ *
+ * Derived from cryptsetup package lib/luks1/af.c
+ *
+ * Copyright (C) 2004, Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2009-2012, Red Hat, Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU 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 "qemu/osdep.h"
+#include "crypto/afsplit.h"
+#include "crypto/random.h"
+
+
+static void qcrypto_afsplit_xor(size_t blocklen,
+ const uint8_t *in1,
+ const uint8_t *in2,
+ uint8_t *out)
+{
+ size_t i;
+ for (i = 0; i < blocklen; i++) {
+ out[i] = in1[i] ^ in2[i];
+ }
+}
+
+
+static int qcrypto_afsplit_hash(QCryptoHashAlgorithm hash,
+ size_t blocklen,
+ uint8_t *block,
+ Error **errp)
+{
+ size_t digestlen = qcrypto_hash_digest_len(hash);
+
+ size_t hashcount = blocklen / digestlen;
+ size_t finallen = blocklen % digestlen;
+ uint32_t i;
+
+ if (finallen) {
+ hashcount++;
+ } else {
+ finallen = digestlen;
+ }
+
+ for (i = 0; i < hashcount; i++) {
+ uint8_t *out = NULL;
+ size_t outlen = 0;
+ uint32_t iv = cpu_to_be32(i);
+ struct iovec in[] = {
+ { .iov_base = &iv,
+ .iov_len = sizeof(iv) },
+ { .iov_base = block + (i * digestlen),
+ .iov_len = (i == (hashcount - 1)) ? finallen : digestlen },
+ };
+
+ if (qcrypto_hash_bytesv(hash,
+ in,
+ G_N_ELEMENTS(in),
+ &out, &outlen,
+ errp) < 0) {
+ return -1;
+ }
+
+ assert(outlen == digestlen);
+ memcpy(block + (i * digestlen), out,
+ (i == (hashcount - 1)) ? finallen : digestlen);
+ g_free(out);
+ }
+
+ return 0;
+}
+
+
+int qcrypto_afsplit_encode(QCryptoHashAlgorithm hash,
+ size_t blocklen,
+ uint32_t stripes,
+ const uint8_t *in,
+ uint8_t *out,
+ Error **errp)
+{
+ uint8_t *block = g_new0(uint8_t, blocklen);
+ size_t i;
+ int ret = -1;
+
+ for (i = 0; i < (stripes - 1); i++) {
+ if (qcrypto_random_bytes(out + (i * blocklen), blocklen, errp) < 0) {
+ goto cleanup;
+ }
+
+ qcrypto_afsplit_xor(blocklen,
+ out + (i * blocklen),
+ block,
+ block);
+ if (qcrypto_afsplit_hash(hash, blocklen, block,
+ errp) < 0) {
+ goto cleanup;
+ }
+ }
+ qcrypto_afsplit_xor(blocklen,
+ in,
+ block,
+ out + (i * blocklen));
+ ret = 0;
+
+ cleanup:
+ g_free(block);
+ return ret;
+}
+
+
+int qcrypto_afsplit_decode(QCryptoHashAlgorithm hash,
+ size_t blocklen,
+ uint32_t stripes,
+ const uint8_t *in,
+ uint8_t *out,
+ Error **errp)
+{
+ uint8_t *block = g_new0(uint8_t, blocklen);
+ size_t i;
+ int ret = -1;
+
+ for (i = 0; i < (stripes - 1); i++) {
+ qcrypto_afsplit_xor(blocklen,
+ in + (i * blocklen),
+ block,
+ block);
+ if (qcrypto_afsplit_hash(hash, blocklen, block,
+ errp) < 0) {
+ goto cleanup;
+ }
+ }
+
+ qcrypto_afsplit_xor(blocklen,
+ in + (i * blocklen),
+ block,
+ out);
+
+ ret = 0;
+
+ cleanup:
+ g_free(block);
+ return ret;
+}