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-rw-r--r--src/crypto/modes/ofb.c107
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diff --git a/src/crypto/modes/ofb.c b/src/crypto/modes/ofb.c
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+/* ====================================================================
+ * Copyright (c) 2008 The OpenSSL Project. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ==================================================================== */
+
+#include <openssl/modes.h>
+
+#include <assert.h>
+
+#include "internal.h"
+
+
+void CRYPTO_ofb128_encrypt(const uint8_t *in, uint8_t *out, size_t len,
+ const void *key, uint8_t ivec[16], int *num,
+ block128_f block) {
+ unsigned int n;
+
+ assert(in && out && key && ivec && num);
+ assert((16 % sizeof(size_t)) == 0);
+
+ n = *num;
+
+ while (n && len) {
+ *(out++) = *(in++) ^ ivec[n];
+ --len;
+ n = (n + 1) % 16;
+ }
+
+#if STRICT_ALIGNMENT
+ if (((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) {
+ size_t l = 0;
+ while (l < len) {
+ if (n == 0) {
+ (*block)(ivec, ivec, key);
+ }
+ out[l] = in[l] ^ ivec[n];
+ ++l;
+ n = (n + 1) % 16;
+ }
+
+ *num = n;
+ return;
+ }
+#endif
+
+ while (len >= 16) {
+ (*block)(ivec, ivec, key);
+ for (; n < 16; n += sizeof(size_t)) {
+ *(size_t *)(out + n) = *(size_t *)(in + n) ^ *(size_t *)(ivec + n);
+ }
+ len -= 16;
+ out += 16;
+ in += 16;
+ n = 0;
+ }
+ if (len) {
+ (*block)(ivec, ivec, key);
+ while (len--) {
+ out[n] = in[n] ^ ivec[n];
+ ++n;
+ }
+ }
+ *num = n;
+}