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authormarha <marha@users.sourceforge.net>2010-03-30 12:36:28 +0000
committermarha <marha@users.sourceforge.net>2010-03-30 12:36:28 +0000
commitff48c0d9098080b51ea12710029135916d117806 (patch)
tree96e6af9caf170ba21a1027b24e306a07e27d7b75 /openssl/crypto/modes/ctr128.c
parentbb731f5ac92655c4860a41fa818a7a63005f8369 (diff)
downloadvcxsrv-ff48c0d9098080b51ea12710029135916d117806.tar.gz
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svn merge -r514:HEAD ^/branches/released .
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diff --git a/openssl/crypto/modes/ctr128.c b/openssl/crypto/modes/ctr128.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 "modes.h"
+#include <string.h>
+
+#ifndef MODES_DEBUG
+# ifndef NDEBUG
+# define NDEBUG
+# endif
+#endif
+#include <assert.h>
+
+typedef unsigned int u32;
+typedef unsigned char u8;
+
+# define GETU32(pt) (((u32)(pt)[0] << 24) ^ ((u32)(pt)[1] << 16) ^ ((u32)(pt)[2] << 8) ^ ((u32)(pt)[3]))
+# define PUTU32(ct, st) { (ct)[0] = (u8)((st) >> 24); (ct)[1] = (u8)((st) >> 16); (ct)[2] = (u8)((st) >> 8); (ct)[3] = (u8)(st); }
+
+#define STRICT_ALIGNMENT
+#if defined(__i386) || defined(__i386__) || \
+ defined(__x86_64) || defined(__x86_64__) || \
+ defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64) || \
+ defined(__s390__) || defined(__s390x__)
+# undef STRICT_ALIGNMENT
+#endif
+
+/* NOTE: the IV/counter CTR mode is big-endian. The code itself
+ * is endian-neutral. */
+
+/* increment counter (128-bit int) by 1 */
+static void ctr128_inc(unsigned char *counter) {
+ u32 c,n=16;
+
+ do {
+ n -= 4;
+ c = GETU32(counter+n);
+ ++c; c &= 0xFFFFFFFF;
+ PUTU32(counter + n, c);
+ if (c) return;
+ } while (n);
+}
+
+#if !defined(OPENSSL_SMALL_FOORPRINT)
+static void ctr128_inc_aligned(unsigned char *counter) {
+ size_t *data,c,n;
+ const union { long one; char little; } is_endian = {1};
+
+ if (is_endian.little) {
+ ctr128_inc(counter);
+ return;
+ }
+
+ data = (size_t *)counter;
+ n = 16/sizeof(size_t);
+ do {
+ --n;
+ c = data[n];
+ ++c;
+ data[n] = c;
+ if (c) return;
+ } while (n);
+}
+#endif
+
+/* The input encrypted as though 128bit counter mode is being
+ * used. The extra state information to record how much of the
+ * 128bit block we have used is contained in *num, and the
+ * encrypted counter is kept in ecount_buf. Both *num and
+ * ecount_buf must be initialised with zeros before the first
+ * call to CRYPTO_ctr128_encrypt().
+ *
+ * This algorithm assumes that the counter is in the x lower bits
+ * of the IV (ivec), and that the application has full control over
+ * overflow and the rest of the IV. This implementation takes NO
+ * responsability for checking that the counter doesn't overflow
+ * into the rest of the IV when incremented.
+ */
+void CRYPTO_ctr128_encrypt(const unsigned char *in, unsigned char *out,
+ size_t len, const void *key,
+ unsigned char ivec[16], unsigned char ecount_buf[16],
+ unsigned int *num, block128_f block)
+{
+ unsigned int n;
+ size_t l=0;
+
+ assert(in && out && key && ecount_buf && num);
+ assert(*num < 16);
+
+ n = *num;
+
+#if !defined(OPENSSL_SMALL_FOOTPRINT)
+ if (16%sizeof(size_t) == 0) do { /* always true actually */
+ while (n && len) {
+ *(out++) = *(in++) ^ ecount_buf[n];
+ --len;
+ n = (n+1) % 16;
+ }
+
+#if defined(STRICT_ALIGNMENT)
+ if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0)
+ break;
+#endif
+ while (len>=16) {
+ (*block)(ivec, ecount_buf, key);
+ ctr128_inc_aligned(ivec);
+ for (n=0; n<16; n+=sizeof(size_t))
+ *(size_t *)(out+n) =
+ *(size_t *)(in+n) ^ *(size_t *)(ecount_buf+n);
+ len -= 16;
+ out += 16;
+ in += 16;
+ }
+ n = 0;
+ if (len) {
+ (*block)(ivec, ecount_buf, key);
+ ctr128_inc_aligned(ivec);
+ while (len--) {
+ out[n] = in[n] ^ ecount_buf[n];
+ ++n;
+ }
+ }
+ *num = n;
+ return;
+ } while(0);
+ /* the rest would be commonly eliminated by x86* compiler */
+#endif
+ while (l<len) {
+ if (n==0) {
+ (*block)(ivec, ecount_buf, key);
+ ctr128_inc(ivec);
+ }
+ out[l] = in[l] ^ ecount_buf[n];
+ ++l;
+ n = (n+1) % 16;
+ }
+
+ *num=n;
+}