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authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-24 01:18:25 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-24 01:18:25 +0100
commit26b265cd29dde56bf0901c421eabc7ae815f38c4 (patch)
tree83a5418c96ccde8522bda6614063b665fe5e0ec9 /crypto/memneq.c
parentMerge branch 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86 (diff)
parentcrypto: s390 - Fix aes-cbc IV corruption (diff)
downloadlinux-26b265cd29dde56bf0901c421eabc7ae815f38c4.tar.xz
linux-26b265cd29dde56bf0901c421eabc7ae815f38c4.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu: - Made x86 ablk_helper generic for ARM - Phase out chainiv in favour of eseqiv (affects IPsec) - Fixed aes-cbc IV corruption on s390 - Added constant-time crypto_memneq which replaces memcmp - Fixed aes-ctr in omap-aes - Added OMAP3 ROM RNG support - Add PRNG support for MSM SoC's - Add and use Job Ring API in caam - Misc fixes [ NOTE! This pull request was sent within the merge window, but Herbert has some questionable email sending setup that makes him public enemy #1 as far as gmail is concerned. So most of his emails seem to be trapped by gmail as spam, resulting in me not seeing them. - Linus ] * git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (49 commits) crypto: s390 - Fix aes-cbc IV corruption crypto: omap-aes - Fix CTR mode counter length crypto: omap-sham - Add missing modalias padata: make the sequence counter an atomic_t crypto: caam - Modify the interface layers to use JR API's crypto: caam - Add API's to allocate/free Job Rings crypto: caam - Add Platform driver for Job Ring hwrng: msm - Add PRNG support for MSM SoC's ARM: DT: msm: Add Qualcomm's PRNG driver binding document crypto: skcipher - Use eseqiv even on UP machines crypto: talitos - Simplify key parsing crypto: picoxcell - Simplify and harden key parsing crypto: ixp4xx - Simplify and harden key parsing crypto: authencesn - Simplify key parsing crypto: authenc - Export key parsing helper function crypto: mv_cesa: remove deprecated IRQF_DISABLED hwrng: OMAP3 ROM Random Number Generator support crypto: sha256_ssse3 - also test for BMI2 crypto: mv_cesa - Remove redundant of_match_ptr crypto: sahara - Remove redundant of_match_ptr ...
Diffstat (limited to 'crypto/memneq.c')
-rw-r--r--crypto/memneq.c138
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 */