1 files changed, 138 insertions, 0 deletions
diff --git a/crypto/memneq.c b/crypto/memneq.c
new file mode 100644
index 000000000000..cd0162221c14
--- /dev/null
+++ b/crypto/memneq.c
@@ -0,0 +1,138 @@
+/*
+ * Constant-time equality testing of memory regions.
+ *
+ * Authors:
+ *
+ *   James Yonan <james@openvpn.net>
+ *   Daniel Borkmann <dborkman@redhat.com>
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * 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.
+ *   * Neither the name of OpenVPN Technologies nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS 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 COPYRIGHT
+ * OWNER OR 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 <crypto/algapi.h>
+#ifndef __HAVE_ARCH_CRYPTO_MEMNEQ
+/* Generic path for arbitrary size */
+static inline unsigned long
+__crypto_memneq_generic(const void *a, const void *b, size_t size)
+{
+        unsigned long neq = 0;
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
+        while (size >= sizeof(unsigned long)) {
+                neq |= *(unsigned long *)a ^ *(unsigned long *)b;
+                a += sizeof(unsigned long);
+                b += sizeof(unsigned long);
+                size -= sizeof(unsigned long);
+        }
+#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
+        while (size > 0) {
+                neq |= *(unsigned char *)a ^ *(unsigned char *)b;
+                a += 1;
+                b += 1;
+                size -= 1;
+        }
+        return neq;
+}
+/* Loop-free fast-path for frequently used 16-byte size */
+static inline unsigned long __crypto_memneq_16(const void *a, const void *b)
+{
+#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+        if (sizeof(unsigned long) == 8)
+                return ((*(unsigned long *)(a)   ^ *(unsigned long *)(b))
+                      | (*(unsigned long *)(a+8) ^ *(unsigned long *)(b+8)));
+        else if (sizeof(unsigned int) == 4)
+                return ((*(unsigned int *)(a)    ^ *(unsigned int *)(b))
+                      | (*(unsigned int *)(a+4)  ^ *(unsigned int *)(b+4))
+                      | (*(unsigned int *)(a+8)  ^ *(unsigned int *)(b+8))
+                      | (*(unsigned int *)(a+12) ^ *(unsigned int *)(b+12)));
+        else
+#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
+                return ((*(unsigned char *)(a)    ^ *(unsigned char *)(b))
+                      | (*(unsigned char *)(a+1)  ^ *(unsigned char *)(b+1))
+                      | (*(unsigned char *)(a+2)  ^ *(unsigned char *)(b+2))
+                      | (*(unsigned char *)(a+3)  ^ *(unsigned char *)(b+3))
+                      | (*(unsigned char *)(a+4)  ^ *(unsigned char *)(b+4))
+                      | (*(unsigned char *)(a+5)  ^ *(unsigned char *)(b+5))
+                      | (*(unsigned char *)(a+6)  ^ *(unsigned char *)(b+6))
+                      | (*(unsigned char *)(a+7)  ^ *(unsigned char *)(b+7))
+                      | (*(unsigned char *)(a+8)  ^ *(unsigned char *)(b+8))
+                      | (*(unsigned char *)(a+9)  ^ *(unsigned char *)(b+9))
+                      | (*(unsigned char *)(a+10) ^ *(unsigned char *)(b+10))
+                      | (*(unsigned char *)(a+11) ^ *(unsigned char *)(b+11))
+                      | (*(unsigned char *)(a+12) ^ *(unsigned char *)(b+12))
+                      | (*(unsigned char *)(a+13) ^ *(unsigned char *)(b+13))
+                      | (*(unsigned char *)(a+14) ^ *(unsigned char *)(b+14))
+                      | (*(unsigned char *)(a+15) ^ *(unsigned char *)(b+15)));
+}
+/* Compare two areas of memory without leaking timing information,
+ * and with special optimizations for common sizes.  Users should
+ * not call this function directly, but should instead use
+ * crypto_memneq defined in crypto/algapi.h.
+ */
+noinline unsigned long __crypto_memneq(const void *a, const void *b,
+                                       size_t size)
+{
+        switch (size) {
+        case 16:
+                return __crypto_memneq_16(a, b);
+        default:
+                return __crypto_memneq_generic(a, b, size);
+        }
+}
+EXPORT_SYMBOL(__crypto_memneq);
+#endif /* __HAVE_ARCH_CRYPTO_MEMNEQ */

diff --git a/crypto/memneq.c b/crypto/memneq.c new file mode 100644 index 000000000000..cd0162221c14 --- /dev/null +++ b/crypto/memneq.c
@@ -0,0 +1,138 @@
	1	/*
	2	* Constant-time equality testing of memory regions.
	3	*
	4	* Authors:
	5	*
	6	* James Yonan <james@openvpn.net>
	7	* Daniel Borkmann <dborkman@redhat.com>
	8	*
	9	* This file is provided under a dual BSD/GPLv2 license. When using or
	10	* redistributing this file, you may do so under either license.
	11	*
	12	* GPL LICENSE SUMMARY
	13	*
	14	* Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
	15	*
	16	* This program is free software; you can redistribute it and/or modify
	17	* it under the terms of version 2 of the GNU General Public License as
	18	* published by the Free Software Foundation.
	19	*
	20	* This program is distributed in the hope that it will be useful, but
	21	* WITHOUT ANY WARRANTY; without even the implied warranty of
	22	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	23	* General Public License for more details.
	24	*
	25	* You should have received a copy of the GNU General Public License
	26	* along with this program; if not, write to the Free Software
	27	* Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	28	* The full GNU General Public License is included in this distribution
	29	* in the file called LICENSE.GPL.
	30	*
	31	* BSD LICENSE
	32	*
	33	* Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
	34	*
	35	* Redistribution and use in source and binary forms, with or without
	36	* modification, are permitted provided that the following conditions
	37	* are met:
	38	*
	39	* * Redistributions of source code must retain the above copyright
	40	* notice, this list of conditions and the following disclaimer.
	41	* * Redistributions in binary form must reproduce the above copyright
	42	* notice, this list of conditions and the following disclaimer in
	43	* the documentation and/or other materials provided with the
	44	* distribution.
	45	* * Neither the name of OpenVPN Technologies nor the names of its
	46	* contributors may be used to endorse or promote products derived
	47	* from this software without specific prior written permission.
	48	*
	49	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	50	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	51	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	52	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	53	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	54	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	55	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	56	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	57	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	58	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	59	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	60	*/
	61
	62	#include <crypto/algapi.h>
	63
	64	#ifndef __HAVE_ARCH_CRYPTO_MEMNEQ
	65
	66	/* Generic path for arbitrary size */
	67	static inline unsigned long
	68	__crypto_memneq_generic(const void a, const void b, size_t size)
	69	{
	70	unsigned long neq = 0;
	71
	72	#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
	73	while (size >= sizeof(unsigned long)) {
	74	neq \|= (unsigned long )a ^ (unsigned long )b;
	75	a += sizeof(unsigned long);
	76	b += sizeof(unsigned long);
	77	size -= sizeof(unsigned long);
	78	}
	79	#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
	80	while (size > 0) {
	81	neq \|= (unsigned char )a ^ (unsigned char )b;
	82	a += 1;
	83	b += 1;
	84	size -= 1;
	85	}
	86	return neq;
	87	}
	88
	89	/* Loop-free fast-path for frequently used 16-byte size */
	90	static inline unsigned long __crypto_memneq_16(const void a, const void b)
	91	{
	92	#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
	93	if (sizeof(unsigned long) == 8)
	94	return (((unsigned long )(a) ^ (unsigned long )(b))
	95	\| ((unsigned long )(a+8) ^ (unsigned long )(b+8)));
	96	else if (sizeof(unsigned int) == 4)
	97	return (((unsigned int )(a) ^ (unsigned int )(b))
	98	\| ((unsigned int )(a+4) ^ (unsigned int )(b+4))
	99	\| ((unsigned int )(a+8) ^ (unsigned int )(b+8))
	100	\| ((unsigned int )(a+12) ^ (unsigned int )(b+12)));
	101	else
	102	#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
	103	return (((unsigned char )(a) ^ (unsigned char )(b))
	104	\| ((unsigned char )(a+1) ^ (unsigned char )(b+1))
	105	\| ((unsigned char )(a+2) ^ (unsigned char )(b+2))
	106	\| ((unsigned char )(a+3) ^ (unsigned char )(b+3))
	107	\| ((unsigned char )(a+4) ^ (unsigned char )(b+4))
	108	\| ((unsigned char )(a+5) ^ (unsigned char )(b+5))
	109	\| ((unsigned char )(a+6) ^ (unsigned char )(b+6))
	110	\| ((unsigned char )(a+7) ^ (unsigned char )(b+7))
	111	\| ((unsigned char )(a+8) ^ (unsigned char )(b+8))
	112	\| ((unsigned char )(a+9) ^ (unsigned char )(b+9))
	113	\| ((unsigned char )(a+10) ^ (unsigned char )(b+10))
	114	\| ((unsigned char )(a+11) ^ (unsigned char )(b+11))
	115	\| ((unsigned char )(a+12) ^ (unsigned char )(b+12))
	116	\| ((unsigned char )(a+13) ^ (unsigned char )(b+13))
	117	\| ((unsigned char )(a+14) ^ (unsigned char )(b+14))
	118	\| ((unsigned char )(a+15) ^ (unsigned char )(b+15)));
	119	}
	120
	121	/* Compare two areas of memory without leaking timing information,
	122	* and with special optimizations for common sizes. Users should
	123	* not call this function directly, but should instead use
	124	* crypto_memneq defined in crypto/algapi.h.
	125	*/
	126	noinline unsigned long __crypto_memneq(const void a, const void b,
	127	size_t size)
	128	{
	129	switch (size) {
	130	case 16:
	131	return __crypto_memneq_16(a, b);
	132	default:
	133	return __crypto_memneq_generic(a, b, size);
	134	}
	135	}
	136	EXPORT_SYMBOL(__crypto_memneq);
	137
	138	#endif /* __HAVE_ARCH_CRYPTO_MEMNEQ */